Cl- channels in basolateral renal medullary membranes, VI. Cl- conductance expression in Xenopus oocytes. Cl- channels from basolateral membranes of the mammalian thick ascending limb of Henle differ significantly, in certain of their functional characteristics, from Cl- channels in apical membranes of secretory epithelia such as trachea or small intestine and from certain Cl- channels in the central nervous system. Yet there is no sequence information available about basolateral thick ascending limb Cl- channels. As an initial step in the isolation of a Cl- channel from the thick ascending limb of Henle's loop, we attempted a functional expression of a Cl- conductance in oocytes from Xenopus laevis. Oocytes injected with mRNA isolated from the outer medulla of rabbit kidney had a membrane conductance, measured using a two-electrode voltage clamp, which was sixfold greater than in water-injected oocytes (9.05 +/- 1.56 vs. 1.43 +/- 0.15 microS, respectively). Ion substitution experiments showed the conductance in the RNA-injected oocytes to be Cl- selective. In addition, the Cl(-)-channel blocker diphenylamine-2-carboxylate (1 mM) almost completely inhibited (79 +/- 6%) the increased conductance seen in the RNA-injected oocytes. Fractionation of the mRNA by sucrose gradient centrifugation revealed that peak Cl- channel activity was expressed using an mRNA fraction of 1.8-3.2 kb in size. These results demonstrate that a membrane Cl- conductance can be expressed in X. laevis oocytes injected with size-selected fractions of mRNA from rabbit outer renal medulla.


Oxygen radicals in cerebral ischemia.

Oxygen radicals in cerebral ischemia. Superoxide production was measured as the superoxide dismutase (SOD)-inhibitable portion of nitro blue tetrazolium (NBT) reduction after cerebral ischemia-reperfusion in anesthetized cats equipped with cranial windows. Significant superoxide production was found in the early reperfusion period and continued for more than 1 h after ischemia. Superoxide was not detected in control animals not subjected to ischemia, during ischemia, and at 120 min of reperfusion. After ischemia, the vasoconstrictor response to arterial hypocapnia was reduced. This effect was prevented by pretreatment with SOD plus catalase or by deferoxamine. The response to topical acetylcholine was converted to vasoconstriction after ischemia. The normal vasodilator response reappeared spontaneously at 120 min of reperfusion. The vasodilator response to acetylcholine was preserved in animals pretreated with SOD plus catalase. Blood-brain barrier permeability to labeled albumin and horseradish peroxidase was increased after ischemia. These effects were minimized by pretreatment with SOD and catalase. We conclude that superoxide generation occurs during reperfusion after cerebral ischemia for a fairly long period and that superoxide and its derivatives are responsible at least in part for the vasodilation and the abnormal reactivity as well as for the increase in blood-brain barrier permeability to macromolecules seen after ischemia. Furthermore, the findings suggest that the agent responsible for the vascular abnormalities is hydroxyl radical generated via the iron-catalyzed Haber-Weiss reaction.


Magnitude of beta-adrenoceptor-mediated responses of dog epicardial coronary arteries: inverse relation to diameter. Regional blood flow patterns vary within myocardium to suggest that intrinsic regional differences occur in vasoregulation. Accordingly, we used standard in vitro methodology (isometric force transducer) to study adrenergic responses in epicardial left anterior descending (LAD) artery and right coronary arteries (RCA) obtained from dogs (n = 9). In the presence of propranolol (10(-6) M) and blockers of uptake 1 and 2, norepinephrine (NE) elicited minimal, if any, constriction. After preincubation with phentolamine (10(-6) M) and preconstriction with prostaglandin (PG)F2 alpha or a thromboxane (Tx)A2 analogue, maximum NE relaxation (as % of induced tone) for the RCA was 61 +/- 3 (SE) %, which was significantly greater than the LAD (46 +/- 5%, P < 0.01). ED50 values were not different. Endothelial removal and forskolin relaxations did not change the sensitivity or maximal response between arteries. Expressing beta-adrenoceptor-mediated relaxation as a function of vessel diameter revealed a common regression for RCA and LAD (r = -0.56, P < 0.001). ED50 and diameter were minimally related. Thus the RCA has a greater beta-adrenoceptor response than the LAD in dogs. The difference appears to be reconciled by a common inverse relationship between vessel size and beta-adrenoceptor response. The difference was independent of alpha-adrenoceptor, endothelium, and second messenger processing, suggesting a mechanism based on beta-adrenoceptor density.


Expression of Na(+)-K(+)-ATPase alpha 1- and alpha 3-isoforms in adult and neonatal ferret hearts. We have demonstrated previously that in adult ferret heart two alpha-subunit isoforms of the Na(+)-K(+)-ATPase, alpha(+) and alpha, are expressed. The alpha(+)-isoform may comprise either alpha 2-, or alpha 3-, or both isoforms. The present studies further characterize the alpha(+)-isoform. The alpha(+)-isoform of ferret heart did not react with an alpha 2-specific monoclonal antibody, but rather with two different alpha 3-specific polyclonal antibodies. Electrophoretic mobility of the alpha(+)-isoform in sodium dodecyl sulfate polyacrylamide gel electrophoresis is slower than that of the alpha 2-isoform, but similar to that of the alpha 3-isoform. Limited proteolytic peptide mapping was performed using Staphylococcus aureus V8. Proteolytic fragments were then immunostained with an alpha 3-specific antibody. The peptide maps of ferret heart alpha(+)-isoform and rat brain alpha 3-isoform were identical, as were those of ferret heart alpha(+)-isoform and ferret brain alpha 3-isoform. These results indicate that the alpha(+)-isoform of ferret heart is an alpha 3-isoform. During postnatal development, the same isoforms expressed in the adult ferret heart (alpha 1 and alpha 3), were also expressed in neonatal heart. In adult or neonatal heart alpha 2-isoform was not detectable. Relative abundances of the isoforms in ventricular and atrial tissues differed. Compared with ventricular tissue, left and right atrial tissues expressed much less alpha 3 than alpha 1. It is concluded that, unlike rat heart, alpha 1- and alpha 3-isoforms are expressed in adult ferret heart.(ABSTRACT TRUNCATED AT 250 WORDS)


Endothelin stimulates multiple responses in isolated adult ventricular cardiac myocytes. We have examined the responses to endothelin (ET) in isolated adult cardiac myocytes from both rodent and feline species to assess whether endothelin may have a role in the induction or mediation of cardiac hypertrophy in the adult animal. We have evidence that ET acts by more than one mechanism to promote cell-signaling events believed important in growth regulation. In isolated adult cardiac ventricular myocytes labeled overnight with [3H]inositol, endothelin (ET) promoted a two- to fourfold increase in the accumulation of inositol polyphosphates in a dose-dependent manner with an half-maximal effective concentration (EC50) of approximately 5 nM. In contrast, picomolar concentrations of ET promoted an increase in both the extent and velocity of sarcomere shortening in electrically stimulated myocytes. Pretreatment of cells with pertussis toxin had no effect on the ET-stimulated phosphoinositide hydrolysis, but blocked the ET-stimulated positive inotropic effect. In addition to these early responses to ET, results obtained by Northern blot analysis demonstrate that exposure of isolated cardiac myocytes to 100 nM ET promoted the expression of c-fos and c-zif in both mammalian species. These data demonstrate that ET stimulates multiple cell-signaling pathways in adult mammalian cardiac myocytes. A paracrine mechanism of regulation of adult myocardium is suggested.


Influence of dietary fish oil on mitochondrial function and response to ischemia. Dietary supplementation with marine oils may reduce the incidence of thromboembolism and decrease cardiac arrhythmias during myocardial ischemia. However, function of subcellular organelles isolated from hearts of these animals is impaired. In contrast to studies where marine oil was the sole source of dietary lipid in rats, menhaden oil was used to supplement standard canine laboratory chow. In mitochondria isolated from hearts of dogs fed this diet for 60 wk, the phospholipid content of arachidonic acid was replaced by the n-3 fatty acids, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Mitochondrial levels of linoleic and linolenic acids were not altered. The mitochondrial membrane phospholipid from the menhaden oil-fed dogs demonstrated increased cardiolipin. The respiratory function of heart mitochondria from the menhaden oil-supplemented dogs was not decreased from that of dogs on standard chow only. Increased succinate-supported respiration paralleled increased cytochrome oxidase in mitochondria from menhaden oil-fed dogs. The activity of the cardiolipin-dependent carnitine acylcarnitine translocase was unaffected. Myocardial ischemia decreased mitochondrial respiration in menhaden-fed dogs. Decreased palmitoylcarnitine-carnitine exchange following ischemia resulted from decreased matrix carnitine rather than decreased translocase activity. Normal levels of the essential fatty acids in the n-3-enriched mitochondrial membrane phospholipids appear to eliminate the mitochondrial dysfunction observed in essential fatty acid-deficient membranes.


Downregulation of blood and bone marrow neutrophils decreases expression of acute lung injury in sheep. We have shown that infusion of zymosan-activated plasma (ZAP) in sheep causes acute lung injury and downregulates peripheral blood neutrophils in that elicited superoxide release is reduced for at least 24 h after the infusion. The present study was designed to test the following hypotheses: 1) peripheral blood neutrophils are representative of neutrophils marginated in the pulmonary circulation, 2) blood neutrophils are downregulated because neutrophils developing in bone marrow are similarly affected, and 3) downregulated neutrophils have a reduced capacity to produce tissue injury. In a series of experiments in 21 sheep, we showed that elicited superoxide release was similar in peripheral blood neutrophils and in marginated neutrophils washed out of the pulmonary vascular bed. Measurements of superoxide release from blood and bone marrow neutrophils collected 2-24 h after ZAP infusion revealed progressive downregulation with time and greater downregulation of superoxide release in bone marrow neutrophils compared with peripheral blood neutrophils. Finally, after downregulating peripheral blood neutrophils, subsequent infusion of ZAP in conscious sheep produced sequestration of neutrophils in the pulmonary circulation but failed to produce a sustained increase in lung lymph protein clearance. The results suggest that neutrophil downregulation, as measured in vitro, is expressed in vivo as reduced ability of neutrophils to produce tissue injury when challenged by an activating agent.


Hemoprotein-dependent production of a neutrophil-activating factor from arachidonic acid. Hemoproteins have been suggested to contribute to various forms of tissue injury by catalyzing the peroxidation of lipids. In this study, the ability of hemoglobin to catalyze the production of a neutrophil-activating factor from arachidonic acid was examined. Incubation of arachidonic acid, hydrogen peroxide, and hemoglobin at 37 degrees C for 30 min resulted in the production of a lipid-extractable substance that was chemotactic for neutrophils in vitro and could stimulate leukocyte adherence in vivo. These actions could be inhibited by two leukotriene B4 (LTB4) receptor antagonists. The peroxidation product cross-reacted significantly with an antibody directed against LTB4, but not with an antibody directed against LTC4. The production of this factor was hemoprotein dependent. Immunoreactive LTB4 and biological activity were produced only when hemoglobin, or another hemoprotein, cytochrome c, was present in the reaction mixture. The amount of the factor produced could be increased in a concentration-dependent manner by increasing the amounts of arachidonic acid or hydrogen peroxide in the reaction mixture. The production of this factor could be inhibited by 5-aminosalicylic acid, catalase, or deferoxamine. Separation of the lipid-extractable products of the peroxidation of arachidonic acid on high-performance liquid chromatography revealed that the immunoreactive (with anti-LTB4) and chemotactic substance had a retention time distinct from that of LTB4 and the hydroxyeicosatetraenoic acids. A lipid-extractable substance with significant cross-reactivity to anti-LTB4 could also be produced if plasma was substituted for arachidonic acid in the reaction mixture.(ABSTRACT TRUNCATED AT 250 WORDS)


Recovery of vascular tissue contractile function during sustained endotoxin exposure. Rat aortic rings incubated in vitro with endotoxin (10 ng/ml, 24 h) exhibited marked suppressions of sensitivity and maximum contraction to norepinephrine as well as a significant increase in guanosine 3',5'-cyclic monophosphate (cGMP) levels. Increasing the incubation time to 42 h did not result in greater suppression; instead, these rings showed improved contractile performance and control-level cGMP. Rings incubated with endotoxin for 18 h and then allowed to recuperate in control medium for another 24 h exhibited normal maximal contractions and cGMP levels; however, these rings remained less sensitive to norepinephrine. An endotoxin-neutralizing protein (50 ng/ml) shielded rings from endotoxin-induced contractile suppression if present during incubation but was unable to restore tissue sensitivity to normal levels if present during the 24-h recuperation. These findings show that vascular tissue exposed to endotoxin has a varied and time-dependent ability to counter the effects of endotoxin on contractile function and intracellular cGMP.


Role of intracellular calcium in renal proximal tubule cell volume regulation. Osmoregulatory Ca2+ signaling in hypotonic solutions was studied with videometric techniques in 158 proximal renal tubules isolated from the teleost Carassius auratus. Absence of extracellular Ca2+, hypoxia (23 mmHg), or NaCN (3 mM) did not alter regulatory volume decreases (RVD). Nevertheless, decrements of intracellular Ca2+ via the A23187 ionophore or after intracellular Ca2+ chelation with indo-1/AM (5 microM) inhibited RVD. In tubules depleted of Ca2+, RVD could only be fully elicited when intracellular Ca2+ pulses were given within 1 min after hypotonic stimulation. While inhibition of Ca2+ release from the endoplasmic reticulum (ER) with 8-(diethylamino)octyl 3,4,5-trimethoxybenzoate hydrochloride (TMB-8, 50 microM) blunted RVD, some of its effects could be reversed with the anion carrier tributyltin (1 microM). Dibutyryl adenosine 3',5'-cyclic monophosphate (cAMP, 0.5 and 1.0 mM) and forskolin (0.25 mM) also impeded RVD; however, their effects could be partially reversed with the K+ ionophore gramicidin (0.5 microM). In conclusion, in Carassius auratus proximal renal tubule cells, RVD is activated by an intracellular Ca2+ signal that likely emanates from the ER and not from the extracellular media or the mitochondrial Ca2+ pool. Ca2+ activation of a cAMP-modulated osmoregulatory K+ channel appears to play an important role.


Effect of kinin receptor antagonists on renal hemodynamic and natriuretic responses to volume expansion. The role of kinins in the natriuretic and papillary blood flow (PBF) responses to intravenous administration of 0.9% sodium chloride solution equal to 5% of body weight over 30 min was evaluated using a B1-kinin receptor antagonist (des-Arg9, [Leu8]bradykinin, 2.5 micrograms/min i.v.) and a B2-kinin receptor antagonist (D-Arg, [Hyp3,Thi5,8,D-Phe7]bradykinin, 2.5 micrograms/min i.v.). In control rats, PBF increased 43 +/- 5% after the volume expansion with saline. Administration of the B1-kinin receptor antagonist had no significant effect on basal PBF or the rise in PBF produced by volume expansion. In contrast, administration of the B2-kinin receptor antagonist decreased basal PBF by 18 +/- 3% and prevented the rise in PBF during volume expansion. Urine osmolality was lower in the rats treated with the B1-antagonist and higher in rats infused with the B2-kinin antagonist than in control animals after volume expansion (587 +/- 47 and 1,082 +/- 83 vs. 907 +/- 124 mosmol/kgH2O, respectively). The initial natriuretic response during the first 30 min after volume expansion was similar in rats given vehicle or the kinin antagonists. However, cumulative sodium excretion over the 2-h course of the experiment was significantly lower in the rats given the B2-receptor antagonist than in control rats (92 +/- 7 vs. 101 +/- 9% of the administered load). The B1-kinin receptor antagonist had no effect on cumulative sodium excretion; however, glomerular filtration rate was 30% lower in rats receiving the B1-antagonist than in control rats after volume expansion.(ABSTRACT TRUNCATED AT 250 WORDS)


Risk reduction in sexual behavior: a condom giveaway program in a drug abuse treatment clinic. Just before and 4 months after initiation of a condom giveaway program, a questionnaire regarding sexual behavior and condom acquisition was administered to 103 men attending an outpatient drug abuse treatment clinic. Jars filled with a variety of condoms were placed in every clinic room. Condom taking varied as a function of room. Sixty percent of the subjects reported taking condoms. At follow-up, clients reported increases in condom possession and in use of condoms for vaginal intercourse.


Pathology and treatment of impalpable breast lesions. With the increasing use of mammography, more needle-localized breast biopsies (NLBB) are being done. The purpose of this study was to analyze the pathology of impalpable breast lesions and the impact of NLBB on treatment strategies. From 1985 to 1990, 1,605 NLBB were performed, of which 321 (20%) were malignant. Twenty-five percent of malignant biopsies demonstrated in situ disease only. The average size of all lesions detected was 16 mm, and, for invasive cancer, 12 mm. Eighteen percent of invasive cancers had metastasized to the axillary lymph nodes. Surgical management consisted of mastectomy in 74% of patients and breast conservation treatment (BCT) in 26%. No significant difference in surgical management for women 50 years of age or younger compared with those older than 50 years of age was noted. Although the use of BCT for eligible women is recommended by the National Institutes of Health, it is not widely practiced, possibly reflecting less physician acceptance of BCT. These observations suggest that the detection of smaller, impalpable breast cancers has had no impact on treatment strategies.


Appendicitis in acquired immunodeficiency syndrome. Reports in the surgical literature are few regarding common intra-abdominal disease processes, such as gallstone disease or appendicitis, in patients with AIDS and instead have focused on AIDS-related intra-abdominal diseases that infrequently require surgical intervention unless complicated by bleeding, obstruction, or perforation. A literature review for appendicitis in AIDS patients revealed only 30 well-documented cases drawn from 13 studies, with a 40% perforation rate and frequent delays and errors in diagnosis. A 7-year experience with 28 patients with appendicitis and AIDS from 4 urban San Francisco hospitals is reviewed. There were no perioperative deaths and an 18% postoperative complication rate. Five patients (18%) were found to have normal appendices with other intra-abdominal pathology, and an AIDS-related etiology for appendicitis was discovered in 7 of 23 patients with appendicitis (30%). With the exception of diffuse versus localized abdominal pain, no preoperative symptom or sign was useful in differentiating AIDS-related and non-AIDS-related disease. Aggressive use of ultrasound and abdominal computed tomographic scanning, along with early surgical intervention, is recommended.


The effect of alcohol withdrawal on serum concentrations of Lp(a), apolipoproteins A-1 and B, and lipids. Moderate alcohol consumption is associated with a decreased risk of coronary artery disease. The mechanism of the putative protective effect of alcohol intake, however, remains elusive. Recent studies suggest that a ratio of apolipoprotein A-I/apolipoprotein B and Lp(a) are better indicators of the risk of atherosclerosis than total cholesterol and high density lipoprotein cholesterol. To assess the effect of alcohol on these analytes, we determined the concentration of Lp(a), apolipoprotein A-I, apolipoprotein B, total cholesterol, and high-density lipoprotein cholesterol, and calculated low-density lipoprotein cholesterol in serum of 12 patients meeting DSM-III-R criteria for alcohol dependence at the time of admission for treatment of alcohol withdrawal (before). The analyses were repeated after 4 weeks of supervised abstinence on a locked research unit (after). With abstinence, there was a significant increase in the concentration of Lp(a), the atherogenic index and the ratio of low-density to high-density lipoprotein cholesterol but a significant decrease in total cholesterol, high-density lipoprotein cholesterol, apolipoprotein A-I, and the apolipoprotein A-I/B ratio. Apolipoprotein B and low-density lipoprotein cholesterol showed no significant changes before and after alcohol abstinence. Thus, decreased Lp(a) and increased high-density lipoprotein cholesterol and apolipoprotein A-I may be factors mediating the putative protective effect of alcohol in coronary artery disease.


Continued development and unconditioned stimulus characterization of selectively bred lines of taste aversion prone and resistant rats. This report updates the bidirectional selective breeding of taste aversion (TA) prone (TAP) and TA resistant (TAR) rat lines from the 8th through the 22nd generations. A palatable saccharin solution and the aversive consequences of a cyclophosphamide injection are the respective conditioned stimulus (CS) and unconditioned stimulus (US) of line development. Nonsibling matings within each of the two extremes of TA conditionability have produced TAP and TAR lines having markedly different TA propensities. As previously reported, the substitution of a rotational (i.e., motion sickness) US for cyclophosphamide during TA conditioning also produced characteristic line differences in conditioned taste aversion acquisition. The present report extends the effective line separating USs to include injections of lithium chloride, emetine hydrochloride, and EtOH. A range of EtOH dose levels produced dose-dependent TAs within TAP rats but failed to induce TAs in TAR rats. Following the conclusion of TA testing, the administration of a hypnotic EtOH dose produced equivalent loss of righting capability and equivalent hypothermia in both TAP and TAR rats. The line differences in EtOH induced TA conditionability therefore do not reflect general line differences in EtOH sensitivity. The lines may be useful within studies of biological bases of TA conditionability and animal analog studies of prevention and treatment of alcohol dependence.


The role of instructional set on alcoholic performance. This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states.


Herpesvirus infection of the respiratory tract in patients with alcoholic hepatitis. Respiratory herpesvirus infections have rarely been described in alcoholics. We report four cases of severe respiratory herpesvirus infections in patients with alcoholic liver disease. Two were related to Herpes Simplex Virus and two to Cytomegalovirus. Both chronic alcoholism and severe liver disease induce immunosuppression, which might account for these unusual herpesvirus infections of the respiratory tract. These cases suggest that infections with herpesviruses should be considered in patients with alcoholic liver disease and pulmonary or tracheobronchial disease unresponsive to standard antibiotic therapy. Bronchoscopy, viral culture, and serological tests appear warranted, particularly given the existence of specific therapy.


Severe hypersensitivity reaction to injectable Gallium 67 in a worker exposed to silica. Gallium 67 scintigraphy is employed in the evaluation of workers with possible pneumoconiosis. To our knowledge, however, a severe hypersensitivity reaction following the intravenous injection of Gallium 67 has not been described. We report the case of a worker chronically exposed to silica who developed an allergic cutaneous and severe articular reaction following the injection of Gallium 67 while being investigated for possible silicosis. Hilar adenopathy was noted on the chest roentgenogram and, retrospectively, circulating immune complexes were found in the patient's serum. The presence of a positive prick skin test to benzyl alcohol suggests that this preservative caused the hypersensitivity reaction.


[Studies using S-(+)-ketamine on probands. Endocrine and circulatory reactions, recovery and dream experiences]. Clinically used ketamine is a racemic mixture of two isomers, S(+)- and R(-)-ketamine. The anaesthetic potency of S(+)-ketamine was found to be three times higher than that of R(-)-ketamine. It was the aim of this study to compare the effects of racemic ketamine and S(+)-ketamine on endocrine and cardiovascular parameters, recovery and psychomimetic reactions in young healthy volunteers. 6 women and 4 men between 23 and 38 years were investigated twice in a randomized double blind cross-over design receiving injections of 2 mg/kg BW racemic ketamine or 1 mg/kg BW S(+)-ketamine at an interval of at least 7 days. Samples were taken from a central venous catheter before and 1, 3, 5, 10, 15, 30, 60 and 120 min after injection for analysis of adrenaline, noradrenaline (by high pressure liquid chromatography with electrochemical detection), ADH, ACTH, cortisol (by radio immuno assay), glucose, lactate and free glycerol. In addition, SAP, HR, and arterial oxygen saturation were measured, and return of consciousness and orientation were protocoled. Incidence and assessment of dreams were reported by the volunteers. Adrenaline, noradrenaline, ACTH, cortisol, lactate and free glycerol in plasma as well as SAP and HR increased significantly after injection of both racemic ketamine and S(+)-ketamine. The influence on ADH and glucose was not significant. There were no differences between racemic ketamine and S(+)-ketamine in these parameters. Recovery was significantly improved after administration of S(+)-ketamine. Simple orders were followed after 7.9 +/- 1.1 vs. 9.2 +/- 1.2 min (P = 0.004). Orientation with respect to the person returned after 9.0 +/- 1.8 vs. 11.5 +/- 2.5 min (P = 0.004); with respect to time and location after 10.1 +/- 2.1 min vs. 13.4 +/- 4.0 min (P = 0.007). 18 dreams were reported; assessment was positive in 13 cases and indifferent in 5 cases, none was negative. In 7 of 10 cases, the investigators were able to identify that S(+)-ketamine had been injected. With respect to endocrine and cardiovascular parameters, the pharmacodynamic effects of racemic and S(+)-ketamine were comparable. Because of the significant improvement in recovery and the reduced quantitative drug load, S(+)-ketamine offers a clear clinical advantage compared with currently used racemic ketamine.


Enhancement of firefly luciferase activity by cytidine nucleotides. The temporal pattern of light production by firefly luciferase depends on the ATP concentration. With low concentrations of ATP a constant production of light occurred while at high concentrations of ATP (greater than 10 microM) there was a flash of light followed by a decline in light production. This time course of light production with high ATP concentrations was changed from the flash pattern to a pattern with a constant production of light by several cytidine nucleotides. CTP, CDP, dCTP, dCDP, dideoxyCTP, periodate-oxidized CTP and CDP, and the etheno derivatives of CTP and CDP produced that change. CMP, cytidine, CDP-glycerol, CDP-glucose, CDP-ethanolamine, and benzoylbenzoylCTP either were inhibitory to firefly luciferase or were not effective in changing the flash time course. Coenzyme A and related compounds also changed the time course of light production. The changes in time course produced by either cytidine nucleotides or CoA were inhibited by desulfoCoA. These compounds apparently enhanced light production by promoting the dissociation of the inhibitory product, oxidized luciferin, from the enzyme. When the activating compounds were used with high concentrations of ATP, the sensitivity of assay for firefly luciferase was increased. This increased sensitivity is important when using the firefly luciferase gene as a reporter.


Use of diethyldithiocarbamate for quantitative determination of tellurite uptake by bacteria. We have developed a simple method for the quantitative determination of tellurite in biological media. This assay is suitable for studying tellurite uptake in bacteria and overcomes the problems of older techniques which are time consuming and labor intensive. In earlier protocols diethyldithiocarbamate was reacted with tellurite and the resulting complex was extracted into organic solvents before spectrophotometric determination. In this study, diethyldithiocarbamate was incubated with tellurite at neutral pH to form a yellow colloidal solution. The absorbance of the aqueous yellow sol was used to determine tellurite concentrations in the range of 1 to 50 micrograms/ml (4 to 200 microM) without the need for solvent extraction.


Photogeneration of hydroxyl radicals for footprinting. Hydroxyl radicals yield footprints of DNA-ligand interactions that are uniform in intensity and display single base pair resolution. It is shown here that brief illumination of dilute aqueous solutions of hydrogen peroxide with a standard uv transilluminator can be used to generate hydroxyl radicals for footprinting studies. Photogenerated hydroxyl radicals are used to footprint netropsin, a drug that interacts with the minor groove of DNA. The method presented eliminates two of the reagents used in conventional Fenton-reaction-based hydroxyl radical footprinting. It has the further advantage that the extent of cleavage of the DNA can be precisely regulated by controlling the illumination time. Because light is used to drive the reaction, photogenerated hydroxyl radicals can be used to footprint DNA-ligand interactions under experimental conditions of temperature and pressure inaccessible to Fenton-reaction chemistry.


Quantitation of polymerase chain reaction products by hybridization-based assays with fluorescent, colorimetric, or chemiluminescent detection. In this report two nonradioactive assays for quantitative analysis of polymerase chain reaction (PCR) products are presented. In the first assay, magnetic beads coated with streptavidin were used to capture biotinylated PCR fragments. After hybridization with a hapten-labeled probe, these beads were analyzed either by flow cytometry (method A) or by immunoenzymatic reactions (method B). Using a dilution series of purified PCR products, we consistently found a lower detection limit of 1.5 fmol for method A than the 0.15-fmol limit for method B. In the second assay we used the peroxidase-based enhanced chemiluminescence system in combination with a cooled charge-coupled device camera to quantify PCR fragments that were spotted on membranes. A linear logarithmic response was observed between the amount of light produced within a certain time interval and the number of DNA molecules. With an exposure time of 5 min, a detection limit of 0.15 fmol was found. Longer exposure times did not result in a higher sensitivity. We conclude that the assays are of sufficient sensitivity for application in quantitative PCR strategies. The nonradioactive technology facilitates implementation of these assays in routine settings.


Simultaneous analysis of adenosine 3',5'-cyclic monophosphate accumulation and adenosine 5'-triphosphate metabolism in cultured cells preincubated with [2-3H]adenine. A simple and sensitive method based on metabolic labeling was developed for the simultaneous analysis of cyclic AMP accumulation and ATP metabolism in small numbers of cultured cells. Cells are preincubated overnight with [2-3H]adenine to label the ATP pool to a high specific activity. After cell stimulation the metabolites are extracted in a small volume of aqueous acetic acid and chloroform and separated without further manipulation by one-dimensional thin-layer chromatography and the radioactivity incorporated is determined by liquid scintillation counting. With ATP labeled to about 6 Ci/mmol, the lower limit of cyclic AMP detection is 2 fmol, a sensitivity that is comparable to the radioimmunoassay of acetylated cyclic AMP. In primary neurons and a neural cell line, for example, levels of ATP and its metabolites change when large amounts of cyclic AMP are generated, each with its unique pattern. ATP is also depleted when metabolic energy is consumed concomitantly with stimulation of cyclic AMP production by agonists, probably as a result of an increase in ion pump activity following cation influx. As ATP is utilized for cyclic AMP production and simultaneously for many other processes, an assessment of its metabolism in parallel with that of cyclic AMP is critical. We suggest that the method described here is particularly advantageous over other methods for this purpose.


Selective photochemical modification by trichloroethanol of tryptophan residues in proteins with a high tyrosine-to-tryptophan ratio. We present an improved procedure for the selective modification of tryptophan residues in proteins. A simple, low-cost set-up allows rapid tryptophan photoreaction upon ultraviolet irradiation in the presence of 2,2,2-trichloroethanol. This photochemical reaction is carried out under native conditions, occurs only in the excited state of tryptophan, and yields a single, as yet unidentified, photoproduct. Except for tyrosine, no reaction with other amino acid side chains are known. Stringent photoselection of tryptophan, ensuring that tyrosine residues are not affected, is achieved in situ without the need for an elaborate system of optical filters or lenses. Illumination with a medium-wave uv lamp of samples placed in disposable, dual pathlength, polystyrene fluorescence cuvettes allows treatment of small sample volumes (greater than or equal to 100 microliters) of various optical density. Chromophore accessibility in oligomeric assemblies or protein-nucleic acid complexes can be assessed by this reaction since the integrity of these structures is preserved. Moreover, this technique can be used to evaluate the involvement of tryptophan residues in catalytic or ligand binding processes.


Fluorescence displacement method for the determination of receptor-ligand binding constants. The equilibrium constant for the binding of a spectroscopically invisible ligand to its protein receptor can be determined in a competition experiment, by using a structural analog that contains a reporter group (fluorophor). A novel mathematical treatment of the multiple equilibria allows the analysis to be performed under tight-binding conditions. The equilibrium equation for mixtures of two mutually competitive tight-binding ligands can be expressed in a recursive form, a form in which the dependent variable appears on both sides and the solution is found iteratively. The algorithm is also applicable to the special case of weak binding, where the concentration of the bound ligand can be neglected in the mass balance. The fluorescence displacement method is demonstrated on the determination cyclophilin binding to cyclosporin A (CsA), in competition with its fluorescent derivative, [D-Lys(Dns)]8-CsA.


The synthesis of substrates and two assays for the detection of N-acetylglucosamine-1-phosphodiester alpha-N-acetylglucosaminidase (uncovering enzyme). A method for the synthesis and purification of large quantities of four radiolabeled substrates for quantitation of uncovering enzyme is described. Four substrates, [3H]GlcNAc-alpha-P-Man alpha Me, [3H]GlcNAc-alpha-P-uteroferrin, [3H]GlcNAc alpha-P-Man alpha 1-2Man-O-Me, and [3H]GlcNAc alpha-P-Man9GlcNAc, were enzymatically synthesized using GlcNAc-phosphotransferase from Acanthamoeba castellanii and uridine diphosphate N-acetyl-[3H]glucosamine and, as acceptor, methyl-alpha-D-mannopyranoside (Man alpha Me), uteroferrin, Man alpha 1-2Man-O-methyl, or Man9GlcNAc. The isolation of the [3H]GlcNAc-P-modified product of each reaction is detailed. Two assays for the detection of uncovering enzyme activity using [3H]GlcNAc-alpha-P-uteroferrin and [3H]GlcNAc-alpha-P-Man alpha Me are outlined. The ability to easily synthesize four relevant substrates for uncovering enzyme offers flexibility in assaying uncovering enzyme.


A new, highly sensitive assay for 1,25-dihydroxyvitamin D not requiring high-performance liquid chromatography: application of monoclonal antibody against vitamin D receptor to radioreceptor assay. A new, highly sensitive radioreceptor assay, which does not require high-performance liquid chromatography, has been developed for the determination of 1,25-dihydroxyvitamin D3 (1,25-(OH2)D3) in serum. The assay involves rapid extraction of serum, Sep Pak silica purification, and addition of 1,25-dihydroxyvitamin D3 receptor, radiolabeled 1,25-dihydroxyvitamin D3, bovine serum albumin, and monoclonal antibody to specifically precipitate the receptor. This method is sensitive to 0.3-0.6 pg/tube, with B50 occurring at 5.8 pg/tube. This sensitivity combined with overall recovery of 1,25-dihydroxyvitamin D3 (81.5 +/- 5.2%, n = 50, mean +/- SD) allows the measurement of serum 1,25-(OH)2D3 in duplicates with only 0.5 ml of serum. Intra- and interassay coefficient of variation were 9.5 and 14.6%, respectively. Dilution analysis, analytical recovery of added 1,25-dihydroxyvitamin D3, and comparison with a standard method using HPLC have been used to validate the assay. Serum 1,25-dihydroxyvitamin D3 level was for normal adults, 36.6 +/- 10.5 pg/ml (n = 14); in primary hyperparathyroidism, 98.9 +/- 19.9 pg/ml (n = 16); in chronic renal failure, 17.8 +/- 5.1 pg/ml (n = 12). This method allows large numbers of samples to be processed at once. Further, the method is rapid and provides an accurate assay using small amounts of serum.


A radiometric assay for kynurenine 3-hydroxylase based on the release of 3H2O during hydroxylation of L-[3,5-3H]kynurenine. A rapid and sensitive assay for kynurenine 3-hydroxylase (KH) has been developed. This radiometric assay is based on the enzymatic synthesis of tritiated water from L-[3,5-3H]kynurenine during the hydroxylation reaction. Radiolabeled water is quantified following selective adsorption of the isotopic substrate and its metabolite with activated charcoal. The assay is suitable for detecting 0.1 pmol enzyme activity per minute per milligram protein in tissues displaying low levels of the enzyme. The amount of water produced in the reaction, as calculated from the tritium released, was stoichiometric with the 3-hydroxykynurenine product detected by HPLC. Rat liver KH was characterized by cofactor specificity and kinetic parameters. NADPH was preferred over NADH as coreductant in the reaction. Tetrahydrobiopterin was not a cofactor. The tissue distribution of KH activity in the rat suggested that the majority of active enzyme is located in liver and kidney. Detectable amounts were found in several other tissues, including brain which had low but significant levels of activity in every region assayed.


A method for increasing the yield of properly folded recombinant fusion proteins: single-chain immunotoxins from renaturation of bacterial inclusion bodies. Many proteins produced in Escherichia coli accumulate in inclusion bodies. We have systematically evaluated the parameters that affect the refolding and renaturation of enzymatically active molecules from bacterial inclusion bodies containing a recombinant single-chain immunotoxin, B3(Fv)-PE38KDEL. This recombinant molecule is composed of the variable domains of monoclonal antibody B3 (B3(Fv)) fused to a truncated mutant form of Pseudomonas exotoxin A (PE38KDEL). This immunotoxin kills carcinoma cells in vitro, causes tumor regression in animal tumor models, and is being developed as an anti-cancer therapeutic agent (Brinkmann et al., 1991, Proc. Natl. Acad. Sci. USA 88, 8616-8620). Like many other recombinant proteins, B3(Fv)-PE38KDEL is produced in E. coli in inclusion bodies and must be denatured and refolded to become active. This requires correct folding, formation of native disulfide bonds, and the association of different domains. All these steps are strongly dependent on the renaturation conditions used. Optimum conditions of refolding were obtained by the addition of reduced and oxidized thiol reagents to promote disulfide bond formation and the addition of a labilizing agent such as L-arginine. Furthermore, the necessity to reactivate proteins at low protein concentrations due to its tendency to aggregate at high concentrations was overcome by a step-by-step addition of denatured and reduced protein into the refolding solution. This approach should be useful for the production of active forms of other recombinant proteins.


Monitoring of iron(III) removal from biological sources using a fluorescent siderophore. We present here the physicochemical and biochemical properties of NBD-DFO, the 7-nitrobenz-2-oxa-1,3-diazole (NBD) derivative of the siderophore, desferrioxamine B (DFO) (Lytton et al., Mol. Pharmacol. 40, 584, 1991). Modification of DFO at its terminal amine renders it more lipophilic, imparts to it fluorescent properties, and is conservative of the high-affinity iron(III) binding capacity. NBD-DFO partitions readily from aqueous solution into n-octanol (Pcoeff = 5) and displays solvent-induced shifts in absorption and fluorescence spectra. The relative quantum yield of the probe's fluorescence increases over a 10-fold range with decreasing dielectric constant of the solvent. Fluorescence is quenched upon binding of iron(III) to the probe. We demonstrate here the application of NBD-DFO for the specific detection and monitoring of iron (III) in solutions and iron(III) mobilization from cells. Interactions between fluorescent siderophore and the ferriproteins ferritin and transferrin were monitored under physiological conditions. Iron removal from ferritin was evident by the demonstrable quenching of NBD-DFO fluorescence by scavenged iron(III). Quantitation of iron sequestered from cells by NBD-DFO or from other siderophore-iron(III) complexes was accomplished by dissociation of NBD-DFO-Fe complex by acidification and addition of excess ethylenediamin-etetraacetic acid. The sensitivity of the method and the iron specificity indicate its potential for monitoring chelatable iron under conditions of iron-mediated cell damage, iron overload, and diseases of iron imbalance such as malaria.


Coelenterazine is a superoxide anion-sensitive chemiluminescent probe: its usefulness in the assay of respiratory burst in neutrophils. The oxidation of free coelenterazine by superoxide anion was analyzed and compared to the oxidation by the semisynthetic photoprotein obelin, prepared by incorporation of synthetic coelenterazine into apoobelin. The oxidation of bound coelenterazine was triggered upon binding of calcium to the reconstituted photoprotein. The oxidation of free synthetic coelenterazine, in the absence of the apoprotein, was triggered by superoxide anion. The production of reactive oxygen metabolites by fMet-Leu-Phe- and 4b-phorbol 12b-myristate 13a-acetate-stimulated neutrophils was studied by means of the luminescence of synthetic coelenterazine. The features of this chemiluminescent probe were compared with those of luminol and are summarized as follows: (a) coelenterazine-dependent chemiluminescence was inhibited by superoxide dismutase; (b) coelenterazine was as sensitive as luminol in detecting the oxidative burst of neutrophils; (c) azide failed to inhibit coelenterazine chemiluminescence; (d) in contrast with luminol, which requires the catalytic removal of hydrogen peroxide, coelenterazine chemiluminescence did not depend on the activity of cell-derived myeloperoxidase. These results indicate the usefulness of coelenterazine as a very sensitive and specific chemiluminescence probe of superoxide anion.


Evaluation of N-hydroxy-2-thiopyridone as a nonmetal dependent source of the hydroxyl radical (HO.) in aqueous systems. N-hydroxy-2-thiopyridone (1), an established source of the hydroxyl radical (HO., Boivin, J., Crepon, E., and Zard, S. Z. (1990) Tetrahedron Lett. 31, 6869-6872), produced HO. under conditions directly applicable to biological studies. Generation of HO. by subjecting 1 to irradiation with visible light was monitored in the following "HO." assays: deoxyribose degradation, addition to dimethyl sulfoxide, and hydroxylation of salicylate and phenol. All four assays demonstrated the production of HO. from 1 (added as a sodium salt) under mild conditions in aqueous buffer systems. An improved analysis method was developed for the phenol assay. A time course analysis demonstrated that a flux of HO. is generated from 1 throughout the irradiation period, in contrast to the classical Fenton reaction of H2O2 with a transition metal in which a burst of HO. is generated in a short time period. While a thiyl radical is generated from 1 concurrent with HO. generation, this species does not contribute to, or interfere with, any of the HO. assays, suggesting that it is weakly reactive in aqueous buffers. Thus, irradiation of 1 can be used as an alternative, complementary, approach for the unequivocal generation of the biologically significant and reactive HO..


A method for evaluating the effects of ligands upon Gs protein-coupled receptors using a recombinant melanophore-based bioassay. As an increasing number of medically important receptors that couple to stimulatory guanine nucleotide (Gs) proteins are isolated and cloned, there is an equally escalating need for methods to rapidly and reproducibly evaluate potential ligands for their properties as agonists or antagonists. Recently, a bioassay that can quickly and accurately determine the effects of numerous chemicals on a beta 1-like adrenergic receptor (AR) endogenous to melanophores derived from Xenopus laevis was developed. Here, the general utility of the melanophore-based pigment dispersion assay is demonstrated by employing it to evaluate the effects of drugs on a human beta 2 AR. Melanophores were both transiently and stably transfected with a plasmid encoding a beta 2 AR. Stimulation of recombinant cells expressing the beta 2 AR, but not wild-type cells, with beta 2-selective agonists induced pigment dispersion and concomitant elevations in intracellular cAMP. Using a microtiter plate reader, it was straightforward to construct reproducible dose-response curves and rapidly determine rank-order potency and EC50 and IC50 values for agonists and antagonists, respectively. The demonstration of functional expression of a human beta 2 AR in the melanophore-based bioassay suggests that the system may be used for the rapid pharmacological characterization of ligands upon any specific Gs-linked receptor for which a cDNA clone is available.


An anion-exchange radioassay for glucose 6-phosphate phosphatase: use in topological studies with endoplasmic reticulum vesicles. A simple procedure is presented for the enzymatic preparation of [2-3H]mannose 6-phosphate (Man 6-P) with purified yeast hexokinase and unlabeled ATP. The enzymatically synthesized [2-3H]Man 6-P is utilized as the radiolabeled substrate in a new rapid assay for glucose 6-phosphate (Glc 6-P) phosphatase. The principle of the assay procedure is that the unreacted substrate, [2-3H]Man 6-P, is retained by the anion-exchange resin, AG 1-X8 (acetate), while the enzymatic product, [2-3H]-mannose, is eluted directly into a scintillation counting vial. When Glc 6-P phosphatase activity associated with mouse liver endoplasmic reticulum (ER) vesicles is assayed by the new chromatographic assay, the same characteristic latency and properties are observed, as determined by the commonly used colorimetric assay of inorganic phosphate produced. The anion-exchange radioassay described should be useful for a variety of topological studies on enzymes associated with membrane vesicles derived from liver and kidney ER.


High efficiency cell-free synthesis of proteins: refinement of the coupled transcription/translation system. Two modifications are introduced to convert the Escherichia coli cell-free extract ("S30") into a high efficiency system for coupled transcription/translation of exogenously added genes. (a) The ribosome fraction collected from the S30 by ultracentrifugation is used. It contains all the proteins necessary for gene expression but has lost the vast majority of soluble proteins that might interfere with purification and enzymatic activity of product formed. (b) Plasmids containing coding sequences to be expressed are not linearized thus enhancing their stability by avoiding their degradation. These two modifications not only improve protein synthesis in a static system but allow gene expression over 20-40 h in the continuous-flow cell-free system. Both prokaryotic and eukaryotic proteins have been synthesized in this system.


Effect of K+ channel blockade with tetraethylammonium on anesthetic-induced relaxation in canine cerebral and coronary arteries. The mechanism by which volatile anesthetics produce their direct effects on vascular smooth muscle remains unknown. The authors previously reported that volatile anesthetics decrease both Ca2+ and K+ currents, however the role of Ca(2+)-activated K+ channels during the vasorelaxation by anesthetics has not been investigated. The purpose of this study was to determine whether blockade of the K+ channel alters the response to volatile anesthetics. Responses were studied in canine middle cerebral arteries and proximal and distal canine coronary arteries. Vascular rings (2-mm length) were suspended in tissue baths, and isometric tension was recorded. Rings were constricted with 40 mM KCl and prostaglandin F2 alpha (middle cerebral arteries only) and subsequently exposed to enflurane (3.25%), halothane (1.35%), and isoflurane (2.1%). Volatile anesthetics produced vasorelaxation with relative potency in order: enflurane > halothane > isoflurane. The procedure was repeated in the presence of the K+ channel blocker tetraethylammonium chloride (TEA, 20 mM). In all groups of vessels TEA alone elicited either no increase or only a transient increase in tension, however constrictions to both agonists were augmented in the presence of TEA. The presence of TEA significantly augmented anesthetic-induced vasorelaxation in small and large coronary vessels and in middle cerebral arteries. However, this effect was more pronounced in the cerebral as compared to coronary arteries. Constrictions produced in cerebral vessels by 15 microM prostaglandin F2 alpha were comparable with constrictions produced by 5 microM prostaglandin F2 alpha in the presence of TEA. The subsequent relaxant response of these vessels to enflurane was also comparable in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Microangiopathy of ethylic polyneuropathy. The authors have studied, by biopsy of the tip of the big toe, the histologic changes in microvessels of patients affected by ethylic polyneuropathy. Patients affected by diabetes, hypertension, peripheral arterial or venous diseases, or dermatologic diseases or vasculitides were excluded. The mean of daily drinks was 310 +/- 105 g of alcohol, chiefly wine. Important pathologic modifications were noted; complete narrowing of the arteriovenous anastomosis, regressive changes of the Vater-Pacini corpuscles, and dilatation of the small veins and the capillaries. The findings were compared with those of a patient affected by ulcerans and mutilans acropathy of Bureau and Barriere, a typical disease of alcoholics. The same characteristics appeared: profound changes of the structure of the smallest vessels, with sclerosis, extended to the interstitium. In a previous study of the authors, 3 other patients affected by Bureau-Barriere disease showed the same pattern. These alterations can be explained as the effect of alcohol on the microvessels.


Ovine mitochondrial DNA: restriction enzyme analysis, mapping and sequencing data. Restriction endonuclease fragment patterns of mitochondrial DNA (mtDNA) in sheep were analysed with 11 enzymes. Four breeds (Merinolandschaf, Rhoenschaf, Schwarzkoepfiges Fleischschaf and Skudde) of domestic sheep and European Mouflon were examined. A restriction map with 28 cleavage sites of seven enzymes was established. KpnI and PstI do not cut ovine mtDNA. Two EcoRI fragments of Merinolandschaf, Rhoenschaf and Mouflon each were cloned and partially sequenced. Intraspecific nucleotide sequence differences within 1.101 kb ranged from 0.09 to 0.27%. Hybridization analysis with a fragment of porcine mtDNA along with sequencing data from cloned fragments was used for orientation of the restriction map along the bovine sequence. Ovine mtDNA sequences encompassing parts of the Cyt.b-, ND5-, CoIII- and ATPase6 genes were compared with the corresponding sequences of the bovine mtDNA.


Inert gas single-breath washout and structural alteration of respiratory bronchioles. With the perspective of establishing a link between a respiratory function test and alterations of membranous bronchioles, respiratory bronchioles, and alveolar ducts, we performed forced expirations and four kinds of single-breath washout maneuvers on 27 men due to undergo a lobectomy for peripheral bronchial carcinoma. For the single-breath washouts, the inhaled gas mixture consisted of 90% O2, 5% He, 5% SF6. The four maneuvers were the standard vital capacity test and three successive inhalations of 0.5, 1, and 1.5 L from functional residual capacity. The slopes of N2, He, and SF6 for each maneuver were computed, as well as a new index (I2) describing the relative decrease of the difference between the SF6 and the He slopes induced by a larger inspiratory volume. The histologic analysis focused on pigmentation, inflammation, and fibrosis of membranous bronchioles, respiratory bronchioles, and alveolar ducts. There was a linear relationship with a highly significant correlation coefficient between the new index I2 and the degree of inflammatory (r = 0.73) and fibrotic (r = 0.63) changes of the respiratory bronchioles; this correlation persisted in patients with a normal FEV1/VC ratio. These preliminary data open the way to finding a test for early peripheral (intraacinar) airway dysfunction.


Validity of enlarged mediastinal nodes as markers of involvement by non-small cell lung cancer. To assess the validity of enlarged mediastinal nodes as markers of involvement for staging in non-small cell lung cancer, we studied the records of 167 consecutive patients who underwent thoracotomy for this disease in the last 4 yr in our center. Careful search for both hilar (N1) and ipsilateral mediastinal nodes (N2) was done in every case. All nodes found at thoracotomy (regardless of their size) were either removed or sampled and then sent to the pathology department for examination. We found enlarged nodes (larger than 10 mm) in 131 of the 167 patients included in the study (72%). Of these patients, 58 had enlarged nodes at the hilar level (presumably N1 disease, 38%), and 73 were considered as presumably N2 at thoracotomy, before pathologic examination (62%). Only 12 of 58 patients with presumably N1 disease had true neoplastic involvement at this level (21%), whereas there was true N2 disease in only 18 of 73 patients with enlarged mediastinal nodes (25%). The positive predictive value for N2 in epidermoid carcinoma was 23%, and it was even lower with adenocarcinoma (18%). We conclude that open surgery with careful sampling is the method of choice for evaluation of mediastinal nodes in non-small cell lung cancer if evidence of malignant involvement cannot be proven histologically before thoracotomy.


Effects on the isolated human bronchus of SR 48968, a potent and selective nonpeptide antagonist of the neurokinin A (NK2) receptors. Tachykinins produce concentration-dependent contraction of the human isolated bronchus by stimulation of receptors that belong to the NK2 type. The aim of this study was to investigate the inhibitory effects of a new, potent, and selective nonpeptide antagonist of the neurokinin A (NKA) (NK2) receptors, SR 48968 [(S)-N-methyl-N-[4-acetylamino-4-phenylpiperidino-2-(3,4-dichlorophenyl) butyl]benzamide] on human isolated airways. Our experiments were performed on human isolated bronchi obtained from patients with lung cancer. Phosphoramidon, 10(-5) M, was added to the bath to inhibit neurokinin metabolism. SR 48968 induced a parallel shift to the right of the concentration-response (C/R) curves to [Nle10]-NKA(4-10), a specific NK2 receptor agonist. The antagonism was of the competitive type, with a pA2 of 9.40 +/- 0.19 (slope = 0.95 +/- 0.08, n = 13). The (R)-enantiomer of SR 48968 was 100-fold less potent and a noncompetitive antagonist (slope = 0.56 +/- 0.11, n = 8); pA2 and slope of the racemate were 8.86 +/- 0.21 and 1.09 +/- 0.21 (n = 7), respectively. Under similar conditions, racemic CP-96,345, a nonpeptide NK1 antagonist, did not modify the C/R curves to [Nle10]-NKA(4-10) until 10(-7) M. SR 48968 did not modify C/R curves to acetylcholine, histamine, KCI, or PGF2 alpha on the human isolated bronchus. Finally, SR 48968 shifted to the right C/R curves to substance P on isolated human bronchi, whereas racemic CP-96,345 was without effect.(ABSTRACT TRUNCATED AT 250 WORDS)


Ganciclovir prophylaxis for cytomegalovirus infections in pulmonary allograft recipients. Cytomegalovirus (CMV) is a substantial cause of morbidity in pulmonary allograft recipients. In an attempt to decrease the prevalence of this infection, we treated 13 recipients at risk for cytomegalovirus with 3 wk of intravenous ganciclovir (5 mg/kg twice a day for 14 days, starting 5 days after the procedure, followed by 1 wk of the drug at a dose of 5 mg/kg/day). Following the ganciclovir course, patients received oral acyclovir, 800 mg three times a day for at least 2 months more. CMV infections developed in 5 recipients (38%), and none of these episodes occurred during the ganciclovir therapy. Neither of the 2 deaths in this group could be attributed to CMV. In comparison, the prevalence of CMV in the preceding cohort of 11 transplant recipients who were administered acyclovir alone was 91% (p << 0.01 by log-rank test), and there were 3 deaths due to viral infections (p = 0.08 by Fisher's exact test). Groups were similar in terms of immunosuppression and renal function during treatment, and none of the recipients developed leukopenia. We conclude that ganciclovir prophylaxis is well tolerated and appears to have considerable efficacy for prevention of CMV infections in pulmonary transplant recipients.


Antimyeloperoxidase autoantibody-associated necrotizing alveolar capillaritis. In this report, we describe 3 patients who had pauci-immune necrotizing alveolar capillaritis-related pulmonary hemorrhage and who never developed other organic involvement, as revealed by clinical and laboratory data and also by autopsy examination in 1 case. Serum samples from these patients disclosed antimyeloperoxidase autoantibodies with initial immunofluorescence titers ranging from 1:1,600 to 1:3,200. Rapid institution of immunosuppressive therapy, as well as plasma exchange, led to prompt clinical improvement in 2 patients who were receiving mechanical ventilation support. We conclude that antimyeloperoxidase autoantibodies become new clues to support an underlying alveolar capillary vasculitis in patients with idiopathic isolated pulmonary hemorrhage, thus facilitating therapeutic decisions in this life-threatening condition.


Endothelin: systemic arterial and pulmonary effects of a new peptide with potent biologic properties. Endothelial cells produce the 21-amino acid peptide endothelin, which is formed from its precursor, big endothelin, via the activity of converting enzyme. The basal production of the peptide is stimulated by epinephrine, angiotensin II, arginine vasopressin, transforming growth factor beta, thrombin, interleukin-1, and hypoxia. In vascular smooth muscle, endothelin binds to a specific receptor (ETA-subtype), which activates phospholipase C, leads to the formation of inositol trisphosphate, diacylglycerol (which activates protein kinase C), and increased intracellular Ca2+. In certain blood vessels, the endothelin receptor on vascular smooth muscle is linked to a voltage-operated Ca2+ channel via a G-protein. This explains why Ca2+ antagonists inhibit endothelin-induced contractions in certain, but not all, blood vessels. In the human forearm circulation, Ca2+ antagonists do prevent endothelin-induced contractions and unmask endothelin-induced vasodilation mediated by endothelial prostacyclin production (via the ETB-receptor). The pulmonary circulation plays an important role in the metabolism of endothelin, as the lungs take up large quantities of the peptide during passage. Endothelin has profound vasoconstrictor effects in the pulmonary circulation (and also in bronchial tissue), and its production is augmented in pulmonary hypertension. In systemic hypertension, the circulating endothelin levels appear to be normal. In atherosclerosis and other forms of vascular disease, circulating endothelin levels are increased. Thus, endothelin is a potent mediator in the systemic and pulmonary circulation and, in particular, in diseases of the vasculature.


Failure to detect vertical transmission of hepatitis C virus. To search for transmission of hepatitis C virus (HCV) from infected mothers to their infants. Prospective clinical, serologic, and molecular biologic follow-up (at least 3 months) of the infants of mothers with anti-HCV antibody. A county hospital providing primary and referral care in high-risk obstetrics (perinatology). Twenty-three mothers with anti-HCV antibody and their 24 infants. An enzyme-linked immunosorbent assay (EIA) and a four-antigen recombinant immunoblot assay (RIBA) were used to test for anti-HCV antibody; serum HCV RNA was measured in two independent laboratories by reverse transcription and polymerase chain reaction (PCR) using nested primers in the 5'-noncoding region. Infant samples were tested for HCV RNA by PCR at delivery and after 3 to 6 months of follow-up. Each sample was tested at least four times in two independent laboratories. Twenty-nine of 648 mothers (4.5%; 95% Cl, 3.0% to 6.4%) had anti-HCV antibody; these women had 30 babies. Twenty-three mothers and their 24 babies were followed at least 3 months (mean follow-up, 52 weeks). Of the 23 mothers, 21 (91%; Cl, 72% to 99%) had a reactive RIBA; one woman had an indeterminate RIBA and was positive for HCV RNA by PCR. In 16 of 23 mothers (70%; Cl, 47% to 87%), PCR yielded a positive result in both laboratories. The mean maternal alanine aminotransferase (ALT) level was 1.6 times the normal value. All the babies had anti-HCV antibody in cord-blood samples, but antibody disappeared or diminished in strength in interval samples, and no infant had evidence of active production of anti-HCV antibody. Only 1 of 24 (4%; Cl, 0.1% to 21%) cord-blood samples was HCV RNA positive, and none of 24 (0%; Cl, 0% to 14%) follow-up samples was positive for HCV RNA by PCR in either laboratory. Four mothers and one baby had antibody to HIV. Infant anti-HCV antibody is most likely acquired passively in utero, and vertical transmission of HCV is uncommon.


Mother-to-infant transmission of hepatitis C virus. To describe the rate of perinatal transmission of hepatitis C virus (HCV). Follow-up study of newborn children of mothers with chronic HCV infection. A university hospital in Sweden. Fourteen women with chronic HCV infection and their 21 newly born children. Detection of HCV RNA in serum by the polymerase chain reaction and detection of anti-HCV antibody by second generation assays. All mothers were found to be positive for anti-HCV antibody both by second-generation enzyme-linked immunosorbent assay (ELISA) and by second-generation recombinant immunoblot assay (RIBA-2); all also had detectable serum HCV RNA. Two children had long-lasting alanine aminotransferase (ALT) elevations, and one of them became HCV RNA positive. None of the other children developed biochemical hepatitis. However, two additional children had temporary viremia. Only the child with biochemical and biopsy-proven hepatitis and detectable HCV RNA in multiple blood samples actively produced anti-HCV antibody. Mother-to-infant transmission of HCV infection from chronically infected women without human immunodeficiency virus (HIV) infection seems to be uncommon.


Effect of folate on cervical cancer. Synergism among risk factors. Folate deficiency appears to play a crucial role early in cervical carcinogenesis by facilitating the incorporation of HPV genomes at a fragile chromosomal site. Thereafter, multiple nutritional, hormonal, and immunologic factors probably interact in a synergistic manner to determine whether the cell line becomes immortalized and invasive.


New concepts of vitamin D functions.

New concepts of vitamin D functions. Besides its classical actions in calcium metabolism, it is clear that the hormonal form of vitamin D has many new functions, which have only been discovered as a result of following the appearance of its receptor. Furthermore, because of the vitamin D-based endocrine system, the use of vitamin D compounds in treating a variety of diseases has been expanded. We now know that 1.25-(OH)2D3 not only stimulates the intestine to absorb calcium and phosphorus, the bones to mobilize calcium and phosphorus, and the kidney to cause increased renal reabsorption of calcium, but also directly suppresses the parathyroid hormone and is a developmental hormone necessary for the recruitment of cells for osteoclast formation, for female reproduction, for development of skin, and for the treatment of certain malignant conditions.


Syndrome of inappropriate secretion of arginine vasopressin in patients with cancer of the head and neck. The syndrome of inappropriate secretion of arginine vasopressin (AVP) known as the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is associated with a variety of malignant and nonmalignant diseases. Only 17 cases of SIADH have been reported in the literature in association with cancer isolated to the head and neck. A retrospective review of 1,436 patients with head and neck malignancy excluding skin cancer through The University of Iowa Tumor Registry revealed 60 patients with the diagnosis of either SIADH or hyposmolality. A chart review for each of these patients was then done to establish the diagnosis of SIADH through relevant laboratory values and by excluding other causes of hyposmolality and hyponatremia. In 43 of these patients (3%), SIADH was found to be associated only with the cancer of the head and neck. We conclude that the incidence of SIADH in patients with cancer of the head and neck is much higher than previously recognized. As elevated serum AVP levels may not be clinically apparent unless associated with excessive water ingestation, it is possible that an even higher percentage of patients may have increased serum AVP levels.


Total reconstruction of the hypopharynx and cervical esophagus: a 20-year experience. We have reviewed 145 patients who underwent 148 total reconstructions of the hypopharynx and cervical esophagus between 1970 and 1989. The types and numbers of reconstruction included 45 deltopectoral (DP) flaps, 35 musculocutaneous (MC) flaps, 19 colon interpositions, 23 gastric transpositions, and 26 free jejunal transfers. Median hospitalization was 51 days for DP flaps, 24 days for MC flaps, 28 days for colon, 30 days for gastric, and 14 days for jejunum. Median resumption of oral intake was 92 days for DP flaps, 19 days for MC flaps, 12 days for colon, 13 days for gastric, and 9 days for jejunum. Functional failure, defined as the inability to maintain adequate nutrition without tube feedings, was 40% for MC flaps, 42% for colon interposition, 17% for gastric transposition, and 20% for free jejunal transfer. Microvascular free jejunal transfer has become our method of choice for reconstruction of the hypopharynx and cervical esophagus. Gastric transposition is an alternative when resection of the thoracic esophagus is necessary.


Pyrophosphate in synovial fluid and urine and its relationship to urinary risk factors for stone disease. Inorganic pyrophosphate (PPi) measurement in urine and synovial fluid has been established using the PPi-dependent phosphorylation of fructose-6-phosphate and subsequent reduction of dihydroxyacetone phosphate by NADH. The assay is linear up to 200 mumol/L, easy to perform and gives results comparable to more complex methods. Daily urinary output of PPi was independently related to both age (P = 0.0014) and sex (P = 0.0002). Men had higher values than women and older individuals excreted greater amounts. Male stone formers, younger than 45 years, had lower values than age matched male controls (P = 0.012). Younger female stone formers also tended to have lower values. In stone formers' urine significant and independent correlations were found of PPi excretion with urine volume (P = 0.004) and with phosphate excretion (P = 0.008). Oxalate excretion and that of other urine constituents and the degree of supersaturation with common stone-forming salts were not correlated with PPi. PPi excretion was markedly elevated in the urine of two patients with hypophosphatasia. The PPi concentration in synovial fluid from painful, swollen knee joints was elevated, but unrelated to the presence or absence of PPi or urate crystals.


[Catheterization of the inferior petrosal sinus. Its role in the diagnosis of Cushing's syndrome. Experience with 23 explorations]. Selective catheterization of the inferior petrosal sinus has been performed in 23 patients: 11 Cushing's disease, 5 lung carcinoid tumors whose diagnosis has been confirmed by surgery and 7 ACTH-dependent hypercortisolism whose final diagnosis has not yet been proved. The pituitary origin of hormone secretion is accepted if the central-to-peripheral ratio (C/PR) is equal or greater than 2 on basal values and/or during CRF test. On basal values, all subjects but one with confirmed pituitary lesions exhibited a C/PR > or = 2; the carcinoid tumors never exceeded the value of 1.3. After CRF injection, all the pituitary tumors showed an increase in C/PR; one patient with a lung carcinoid tumor (CRF-negative) showed a pituitary ACTH secretion (C/PR = 3.7). The localization of pituitary adenoma by the lateralization of hormone secretion is disappointing, except, perhaps, for very small extremely lateral adenomas. No accident occurred in our series, nor in the literature. This investigation seems the most reliable approach to prove the pituitary origin of hormonal hypersecretion. We recommend it to be performed in ACTH-dependent Cushing's syndrome when the secretory pattern is not typical and/or pituitary imaging is normal.


Reciprocal control of oxytocin and cAMP production by porcine granulosa cells in vitro. Oxytocin and cAMP accumulation in the medium after 4 days incubation of porcine granulosa cells was measured and confirmed the production of these substances by porcine ovaries. Both cAMP analogue dbcAMP (10, 100, 1,000 or 10,000 microM/ml) and 3-isobutyl-1-methyl-xanthine (intracellular cAMP metabolization inhibitor, 0.1, 1, 10 or 100 microM/ml) additions increased granulosa cells oxytocin production in a dose-dependent manner. Low doses of oxytocin or posterior pituitary extract (10 or 100 mIU/ml) had no significant effect on granulosa cAMP output, but higher dose (1,000 mIU/ml) inhibited it. Thus, porcine ovarian oxytocin production can be stimulated via cAMP-dependent intracellular mechanisms. On the other hand, excess of oxytocin can inhibit ovarian cAMP production through a ultra-short loop negative feedback regulation.


[Marijuana and reproduction. Effects on puberty and gestation in female rats. Experimental results]. The main psychoactive component of marihuana, delta-9-tetrahydrocannabiol (THC), was investigated at low doses (1 microgram/kg/day) on the onset of puberty, on the reproductive functions in female rats up to the seventy fifth to eightieth day of life as well as during the pregnancy. The administration of THC caused a delay of the onset of puberty, and the number of ova on the day of first estrus was significantly lower in treated animals. After puberty, alterations occurred in the neuroendocrine functions of animals received THC: estrous cycles were irregular, serum LH level was decreased. When THC was injected during the third week of pregnancy it caused a significant prolongation of the gestation period. There was 30% stillbirths (v.s. 3% in physiological saline treated rats). No teratological effects were observed. Serum LH, progesterone and prostaglandin contents were decreased. The results indicate that marihuana causes alterations in reproductive functions. The importance of fight against drug abuse is emphasized.


A new patient-like metastatic model of human small-cell lung cancer constructed orthotopically with intact tissue via thoracotomy in nude mice. A new nude-mouse metastasizing orthotopic transplant model of human small-cell carcinoma of the lung is described. Histologically-intact human small-cell lung tumors were transplanted to the left lung of nude mice via a thoracotomy procedure we have developed. The transplanted tumors grew extensively locally and metastasized to the opposite lung, lymph nodes and other clinically-relevant sites. The results described indicate the model developed could have clinical relevance and contrasts with models of small-cell carcinoma constructed with injections of cell suspensions which result in few or no metastases.


In situ hybridization for the detection of human papillomavirus (HPV) in gynaecological biopsies. A study of two commercial kits. Human papillomavirus (HPV) detection in biopsies from the lower genital tract may be requested by clinicians as a complement to ordinary histopathological diagnosis. In the present study, two commercial kits, (Enzo Diagnostics Inc., New York, USA and Biohit, Helsinki, Finland) used for in situ hybridization with biotinylated c-DNA probes were compared and the HPV-expression was evaluated in relation to histopathological findings. The Enzo kit identifies HPV-types 6/11, 16/18, 18 and 31/33/51, whereas the Biohit kit has separate probes for HPV 6, 11, 16, 18, 31 and 33, but none for HPV 51. The usefulness of a general probe (probemix) for the visualization of HPV irrespective of type (Enzo Diagnostics Inc.) was also studied Altogether 226 biopsies from the lower female genital tract were formalin-fixed, paraffin-embedded and processed for routine histopathological grading. Consecutive sections were employed for in situ hybridization. 50 biopsies were subject to double-testing with Enzo and Biohit, whereas 176 were tested with Enzo only. Of the double-tested biopsies, 30% displayed a nuclear staining with the Enzo kit and 28% with the Biohit kit. It is concluded that the probes of these two kits have the same sensitivity in detecting HPV in tissue sections. Condylomata acuminata were HPV-positive in 81%, mostly for types 6/11. Flat condylomas were HPV-positive in 35%. The HPV-positivity of biopsies with low grade SIL (I) was 50% and that of high grade SIL (II and III) was 37%. High grade SIL contained either HPV-types 16/18 or 31/33/51. A correlation was found between the occurrence of koilocytosis and the presence of HPV-DNA. HPV-expression was most easily visualized in condylomata acuminata. In epithelium of normal appearance or with inflammatory alterations HPV-DNA was not seen.


Non small cell lung cancer treatment with carboplatin and vindesine: a phase II study. A phase II trial aiming to verify the effectiveness of a regimen including carboplatin and vindesine was performed. From November 1989 to September 1990, nineteen patients with advanced small cell lung cancer entered this study. Polychemotherapy treatment included: carboplatin 400 mg/sm, on day 1 and vindesine 3 mg/sm, on days 1 and 15, repeated every 4 weeks, as an outpatient regimen. Observed toxicity was mild; myelodepression, and nausea and vomiting were the main adverse events. No objective response was obtained; 14 no changes in the disease and 4 progressions were detected. The low objective response rate observed in this study is strongly influenced by a set of unfavourable prognostic factors. The median overall survival time [32 weeks] is comparable with the results of other studies.


Orthotopic reconstitution of human small-cell lung carcinoma after intravenous transplantation in SCID mice. We have constructed an orthotopically reconstituted model of human small-cell lung carcinoma (SCLC) by intravenous transplantation in severe combined immunodeficient (SCID) mice. Two human SCLC xenografts, H-69 and Lu-130, were disaggregated and injected through the tail vein of SCID mice. Human SCLCs were orthotopically reconstituted with multi-focal lung tumor growth in all SCID mice after intravenous injection of 5 x 10(6) tumor cells per mouse. The heart and liver were also seeded with actively growing SCLC. This orthotopic reconstitution model of human SCLC in SCID mice should be useful for further studies on the biological behavior and treatment of human SCLC.


Phenotypic analysis of tumor-infiltrating lymphocytes from human breast cancer. Suspensions of fresh tumor-infiltrating lymphocytes (TIL) were prepared from 30 human breast ductal adenocarcinomas. To evaluate the phenotypic pattern of the isolated TIL, lymphocyte surface markers including CD19, CD3, CD4, CD8, CD16 and HLA-DR were examined by flow cytometry. Lymphocyte recovery ranged from 1.1% to 44%, independent of tumor size. TIL most often scored high for CD3+ with a varying number of CD4+ and CD8+ cells. Three samples out of 30 expressed up to 44% of CD19+ B cells, while CD3-CD16+ NK cells were rare. CD4 and CD8 expression was significantly different between the lymph node metastases group and the lymph node negative group (p < 0.01). 67% of the TIL with a CD4/CD8 ratio greater than 1 showed lymph node metastases. Furthermore, the CD4 expression of TIL and CD4/CD8 ratio correlated with tumor size (p < 0.01), but not with tumor differentiation and hormone receptor expression. Although there was considerable diversity of TIL among breast tumors, our data suggest that a high expression of CD4+ T cells may imply progression of the tumor, and an increased CD4/CD8 ratio of the TIL isolated from human breast adenocarcinoma may indicate development of metastases.


Network of idiotypic and anti-idiotypic antibodies related to the ovarian carcinoma-associated folate binding protein. The present paper describes the generation and characterization of anti-idiotypic monoclonal antibodies (Ab2 MAbs) produced against the MOv19 MAb (Ab1 MAb), which shows a restricted reactivity with human ovarian carcinoma. The Ab2 MAbs were produced by immunizing mice with MOv19 conjugated to syngeneic mouse red blood cells (MRBC). After the somatic hybridization, five Ab2 MAbs, designated Id19.1, Id19.2, Id19.3, Id19.4 and Id19.5, were selected by a sandwich assay on the basis of their specific reactivity to the MOv19 MAb, but not to the isotype-matched MAb used as a control. A complete cross-inhibition between these 5 MAbs was observed, indicating that they recognize overlapping idiotopes on MOv19. The Ab2/antigen relationship of two Ab2 MAbs (Id19.1 and Id19.2) was investigated by competition experiments on a relevant tumor target cell line. We showed that both Ab2 MAbs were able to interfere with the antigen binding capacity of 125I-MOv19. Moreover, Id19.1 was able partially to inhibit the binding of the purified radiolabelled antigen recognized by the MOv19 MAb (125I-CaMOv19) on insolubilized MOv19. To investigate further whether the Ab2 MAb is the "internal image" of CaMOv19, Id19.1 was used as immunogen with the aim to induce an anti-CaMOv19 response. The antisera tested by indirect solid-phase radioimmunoassay (RIA) on the Ab2 MAb and the irrelevant isotype-matched control MAb revealed an anti-anti-idiotypic response (Ab3). However, no Ab3 antibodies with Ab1-like specificity (Ab1') were found in the immune sera, as assessed by testing the antisera both in indirect immunofluorescence (IF) and solid-phase RIA on CaMOv19-positive target cell lines.


[Current features of malignant renal tumors in children]. The diagnosis of nephroblastoma is based on a postulate: any solid intrarenal tumour in a child between the ages of six months and six years is a nephroblastoma and therefore requires preoperative chemotherapy. Fine needle biopsy to obtain histological confirmation is only justified in doubtful cases. The prognosis is dominated by unfavourable, sarcomatous and anaplastic histological forms, which represent less than 10% of all nephroblastomas and are responsible for one half of deaths. Due to the better understanding of the therapeutic sequelae, particularly following radiotherapy, this modality is avoided whenever possible in young children. Radiotherapy is only indicated in stage II, with lymph node invasion, and stage III forms with favourable histology. It is indicated in all forms with unfavourable histology except for stage I anaplastic tumours. Surgery is indicated for metastases, especially lung metastases, once again to avoid irradiation. Lastly, bilateral partial nephrectomy is the best treatment for bilateral nephroblastoma.


Treatment of the picornavirus common cold by inhibitors of viral uncoating and attachment. The human rhinoviruses are the leading cause of the ubiquitous, mild, and self-limiting infections generally referred to as the common cold. Considerable research effort has been expended in the search for well tolerated antiviral agents capable of preventing and treating the common cold. Although no antirhinovirus drug is yet commercially available, considerable progress has been made in the discovery and development of novel, viral specific inhibitors of rhinovirus replication. This report reviews the history and current status of the research that has focused on inhibitors of the early steps in the virus life cycle: attachment to the cellular receptor and uncoating of the viral RNA. Molecules directed at these targets currently possess the greatest potential for generating a safe and efficacious treatment for the rhinovirus common cold.


Clinical value of serum tumour markers CEA, CA 50 and CA 242 in the distinction between malignant versus benign diseases causing jaundice and cholestasis; results from a prospective study. A prospective study of 113 patients with jaundice and 20 patients with unjaundiced cholestasis was carried out to evaluate the value of serum tumour markers, carcinoembryonic antigen (CEA) and monoclonal antibodies CA 50 and CA 242, in the distinction between benign and malignant diseases causing jaundice and/or cholestasis. In the patients with malignant disease (n = 37) the serum values of all tumour markers were significantly higher than in the patients with benign disease (n = 96). The sensitivities of CEA, CA 50 and CA 242 in detecting malignancy were 70.2%, 94.5% and 56.7%, respectively, while the specificities were 57.2%, 33.3% and 77.0%, respectively. Serum alkaline phosphatase and bilirubin levels had a high positive correlation with CA 50, and CA 242 correlated positively with serum bilirubin levels. No correlation was seen between CEA and alkaline phosphatase or bilirubin levels. The CEA, CA 50 and CA 242 tests may be used as useful complements to other investigative methods in the distinction between benign and malignant causes of jaundice and/or cholestasis. In particular, the rather high specificity of the CA 242 test for malignant diseases seems promising.


A study of chromosome 6 allele loss in human colorectal carcinomas. Matched normal/tumor DNA pairs from patients with sporadic and hereditary (FAP = familial adenomatous polyposis) colorectal carcinoma were examined for tumor-specific allele loss on chromosome 6 using cDNA probes for the avian myeloblastosis viral oncogene homologue (MYB on 6q22-q23), the estrogen receptor (ESR on 6q24-q27), and for the alpha polypeptide of human chorionic gonadotropin (CGA on 6q14-q21). No chromosome 6 allele loss was observed at these gene loci among 22 colorectal carcinomas examined, although such losses were relatively frequent (37.5% of informative individuals) at the D17S28 locus on chromosome 17. These results are consistent with karyological studies and indicate that chromosome 6 allele loss from colorectal carcinomas may occur less frequently than previously reported.


Activities of WIN-57273, minocycline, clarithromycin, and 14-hydroxy-clarithromycin against Mycobacterium avium complex in human macrophages. The activities of the fluoroquinolone WIN-57273, 14-OH clarithromycin (a human metabolite of clarithromycin), and minocycline against two virulent strains of Mycobacterium avium complex were evaluated in a model of intracellular infection and compared with that of clarithromycin. Human monocyte-derived macrophages were infected at day 6 of culture. Intracellular CFU at 60 min and intracellular and supernatant CFU on days 4 and 7 were counted after inoculation. The concentrations used, which were equal to peak levels in serum, were 3 micrograms of WIN-57273 per ml (MICs for the two strains, 1 microgram/ml), 4 microgram of 14-OH clarithromycin per ml (MICs, 8 and 2 micrograms/ml, respectively, at pH 7.4), 4 micrograms of minocycline per ml (MICs, 64 and 32 micrograms/ml, respectively), and 4 micrograms of clarithromycin per ml (MICs, 2 and 0.5 micrograms/ml, respectively, at pH 7.4). On day 7, compared with controls, WIN-57273, minocycline (P less than 0.02), clarithromycin, or different combinations of clarithromycin and the other drugs (P less than 0.001) slowed the intracellular replication of strain MO-1. 14-OH clarithromycin (P less than 0.02), clarithromycin (P less than 0.02), 14-OH clarithromycin plus clarithromycin (P less than 0.01), clarithromycin plus minocycline, or clarithromycin plus minocycline plus 14-OH clarithromycin (P less than 0.001) slowed the intracellular replication of strain LV-2. WIN-57273 was less effective than clarithromycin against strain MO-1 (P less than 0.05). Clarithromycin plus 14-OH clarithromycin plus minocycline (P less than 0.02) was more effective than clarithromycin alone against strain LV-2. Thus, clarithromycin plus minocycline, which corresponds in humans to three active molecules, may exhibit a better efficacy than clarithromycin in this model.


X-raying of sliced surgical specimens during surgery: an improvement of the histological diagnosis of impalpable breast lesions with microcalfications. Surgical specimens, from 78 patients operated for impalpable breast lesions containing microcalcifications detected on mammographs (breast cancer screening program) were systematically examined by a pathologist during the surgical intervention. The per-operative procedures encompassed (i) X-raying of the unfixed specimens to ascertain that the latter did enclose the screened lesion, (ii) slicing and subsequent X-raying of the specimens slices in order to locate the microcalcifications, (iii) histological evaluation of areas containing the microcalcifications on frozen sections. Thirty-two of the lesions were histologically benign, 55% were malignant and 13% borderline. Forty of the carcinomas were in situ and 60% were invasive. The per-operative histological diagnosis was correct in 65% of the case, erroneous in 10% and uncertain in 25%. Malignancy was never overscored. In 65% of the carcinomas diagnosed during the surgical intervention, the in sano margins excision and axillary lymph node removal could be performed (one stage surgical treatment). These results suggest that X-raying of sliced specimens and histological evaluation during the surgical intervention ascertains that lesions screened by mammographs are effectively and completely removed, and that they are precisely and extensively histologically examined after being identified and located.


In vitro and in vivo antibacterial activities of AM-1155, a new 6-fluoro-8-methoxy quinolone. AM-1155 is a new quinolone with a wide spectrum of antibacterial activity against various bacteria including anaerobes and Mycoplasma pneumoniae. AM-1155 was 2- to 16-fold more active than ciprofloxacin and ofloxacin against Staphylococcus aureus including methicillin-resistant strains, Staphylococcus epidermidis, Streptococcus pneumoniae, and Enterococcus faecalis; its MICs for 90% of strains tested were 0.10 to 0.78 micrograms/ml. The activity of AM-1155 was comparable to that of ciprofloxacin against members of the family Enterobacteriaceae, Branhamella catarrhalis, Haemophilus influenzae, and Neisseria gonorrhoeae, but was fourfold less than that of ciprofloxacin against Pseudomonas aeruginosa. Against Xanthomonas maltophilia, Acinetobacter calcoaceticus, and Campylobacter jejuni, AM-1155 was two- to fourfold more active than ciprofloxacin. At a concentration of 1.56 micrograms/ml, AM-1155 inhibited 90% of Bacteroides fragilis strains tested; its activity was 8- to 10-fold higher than those of ofloxacin and ciprofloxacin. Development of resistance to AM-1155 in S. aureus and S. epidermidis occurred at a lower frequency than did that to ciprofloxacin after eight transfers in the presence of drug. In the oral treatment of mouse systemic infections, AM-1155 was four- to eightfold more effective than ciprofloxacin against gram-positive cocci and was as active as ciprofloxacin against gram-negative rods. The efficacy of an oral or a subcutaneous dose of AM-1155 was two- to fivefold greater than that of ofloxacin. Against experimental pneumonia with Klebsiella pneumoniae and P. aeruginosa, AM-1155 was two- to fourfold more active than ciprofloxacin and ofloxacin. AM-1155 also had good efficacy against mouse ascending urinary tract infections with Escherichia coli and P. aeruginosa. These results suggest that AM-1155 may be a potent antibacterial agent applicable to various infections.


Characterization of DNA topoisomerase I from Candida albicans as a target for drug discovery. Candida albicans is an opportunistic pathogen responsible for life-threatening infections in persons with impaired immune systems. Topoisomerase I is a potential target for novel antifungal agents; however, in order for this enzyme to be a therapeutically useful target, it needs to be demonstrated that the fungal and human topoisomerases differ sufficiently as to allow the fungal topoisomerase to be selectively targeted. To address this question, we isolated the topoisomerase I from C. albicans and compared its biochemical properties with those of the mammalian enzyme. Similar to other eukaryotic type I topoisomerases, the C. albicans type I topoisomerase has an apparent molecular mass of 102 kDa and covalently links to the 3' end of DNA, as shown after the reaction is interrupted by sodium dodecyl sulfate. Topoisomerase poisons such as camptothecin act by stabilizing the cleavage complex formed by the topoisomerase I and DNA. We observed that the C. albicans and mammalian type I topoisomerases differ in that the C. albicans cleavage complex is approximately 10-fold less sensitive to camptothecin than the mammalian cleavage complex is. In addition, we found that the antifungal agent eupolauridine can stabilize the cleavage complex formed by both the C. albicans and human topoisomerases and that the response of the C. albicans topoisomerase I to this drug is greater than that of the human enzyme. Thus, the topoisomerase I from C. albicans is sufficiently distinct from the human enzyme as to allow differential chemical targeting and will therefore make a good target for antifungal drug discovery.


Comparative in vitro activities of a new quinolone, OPC-17116, possessing potent activity against gram-positive bacteria. The in vitro antibacterial activity of OPC-17116, a new fluoroquinolone, against a wide variety of clinical isolates was evaluated and compared with those of ciprofloxacin, ofloxacin, and norfloxacin. OPC-17116 showed potent broad-spectrum activity against gram-positive and -negative bacteria. The activity of this compound against gram-positive bacteria was higher than those of other quinolones, and its activity against gram-negative and anaerobic bacteria was roughly comparable to those of other quinolones. OPC-17116 had potent activity against important pathogens of respiratory tract infections such as Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Haemophilus influenzae, and Branhamella catarrhalis. The MICs of this compound against 90% of these organisms, except for methicillin-resistant S. aureus, ranged from less than or equal to 0.006 to 3.13 micrograms/ml. OPC-17116 at more than one-half the MICs was bactericidal against clinical isolates of S. aureus, Escherichia coli, K. pneumoniae, and P. aeruginosa. The activity of OPC-17116 was decreased by several culture conditions such as acidic pH, high concentration of Mg2+ ions, and inoculum size of 10(7) CFU/ml. OPC-17116 inhibited the supercoiling activity of DNA gyrases from E. coli KL-16 and S. aureus SA113 (50% inhibitory concentrations, 0.19 and 23.0 micrograms/ml, respectively). The amount of OPC-17116 accumulation was higher than that of other quinolones in S. aureus.


Efficacy of temafloxacin in experimental Streptococcus adjacens endocarditis and autoradiographic diffusion pattern of [14C]temafloxacin in cardiac vegetations. Temafloxacin, a new fluoroquinolone, alone or in combination with tobramycin, was compared with penicillin, tobramycin, and their combination in the therapy of rabbits with endocarditis caused by Streptococcus adjacens GaDT, a new species of nutritionally variant streptococci. Animals were injected intramuscularly for 4 days with temafloxacin (50 mg/kg of body weight twice daily [b.i.d.]) alone or combined with tobramycin (12 mg/kg once daily), with procaine penicillin (150,000 U/kg b.i.d.) alone or combined with tobramycin (12 mg/kg once daily), or with tobramycin (12 mg/kg once daily) alone. Another group of animals was treated with a higher dose of temafloxacin (100 mg/kg b.i.d.). Temafloxacin, penicillin, and tobramycin MICs and MBCs were 1 and 2, 0.015 and 1, and 8 and 16 micrograms/ml, respectively. Time-kill curves showed that the addition of tobramycin to penicillin or temafloxacin increased the killing rate. In vivo, treatment with temafloxacin (50 and 100 mg/kg b.i.d.) alone reduced the bacterial counts in vegetations (3.9 +/- 0.9 and 3.1 +/- 0.8 log10 CFU/g of vegetation) compared with those in the vegetations of control animals (7.5 +/- 0.9 log10 CFU/g of vegetation). This result was similar to that obtained with penicillin alone (4.5 +/- 0.8 log10 CFU/g of vegetation). The combination of temafloxacin (50 mg/kg) and tobramycin was as effective as penicillin plus tobramycin (2.5 +/- 0.3 versus 2.3 +/- 0.4 log10 CFU/g of vegetation, respectively). The autoradiographic pattern of [14C]temafloxacin diffusion into infected cardiac vegetations was studied. Thirty minutes after the end of infusion of 250 microCi of [14C]temafloxacin, the [14C]temafloxacin was homogeneously distributed throughout the vegetations. These data support further evaluation of quinolones in experimental endocarditis.


Antileishmanial drug targeting through glycosylated polymers specifically internalized by macrophage membrane lectins. Antileishmanial chemotherapy is hampered by the location of the parasite within the phagolysosome of the macrophage, which restricts the bioavailability of many potentially useful antileishmanial drugs. In this study, the possibility of using antileishmanial drugs targeted to the infected macrophages by means of a chemical linkage to a neutral mannose-substituted poly-L-lysine carrier molecule was explored. The study was performed in an in vitro model with Leishmania donovani-infected murine macrophages. The antileishmanial activities of various synthetic constructs were compared with those of the free drugs and the pentavalent antimonial Pentostam, which was used as the positive control. The 50% effective dose of allopurinol riboside linked to the mannosylated poly-L-lysine was below 7.5 x 10(-6) M, while it was up to 3 x 10(-4) M for the free drug, indicating that the drug bound to the polymer was 50 times more active than the free drug. Control experiments with other constructs (e.g., allopurinol riboside linked to the mannose-free polymer) confirmed that the enhancement of activity was indeed achieved by means of the mannose homing device.