[The dynamics of the individual profiles of brain asymmetry in patients with craniocerebral trauma under the influence of emoxipin treatment]. The authors studied the effect of the drug emoxypin on the brain functional asymmetry (A) in 36 patients with craniocerebral trauma attended by occurrence of focal traumatic injuries (FTI) to the brain (experimental group). The control group consisted of 61 patients who received the traditional intensive therapy for FTI (isolated brain contusion of moderate and severe degree, intracerebral hematomas measuring 30-50 cm3 in volume in the contusion focus). Favorable changes of the brain FA indices in the individual asymmetry profiles were noted, respectively, in 76.7% and 40.9% of patients given and not given emoxypin. Complete normalization of brain FA indices by the 25th-30th day after the beginning of treatment was recorded in 60.9% of patients in the control group and in 37% of those in the experimental group. The dynamics of individual asymmetry profiles in patients with FTI provides evidence that emoxypin improves the attention, mental efficiency, memory capacity, and selectivity of mnemonic processes.


[The correlation of the parameters of the circulus arteriosus cerebri and of the main cerebral arteries and their variability in circulus arteriosus anomalies]. The authors examined 414 brain preparations of males and females to study the correlation of the size of the circulus arteriosus cerebri (CAC) with the brain mass (BM) and the size of the skull, and the correlation between the area of the cross-section of the lumen (CSL) of arteries contributing to the formation of the circulus arteriosus, as well as that of the vertebral and basilar arteries with the BM. The age-specific changes of the diameters of the cerebral arteries and the variability of their parameters in CAC anomalies were studied. The CAS cross-section is larger in males than in females. The size of the CAS does not correlate with the BM. Direct correlative relations between CSL of the cerebral vessels and the BM were revealed. The diameter of the cerebral vessels is larger in males than in females. The diameter of all arteries increases from the first period of maturity to elderly age, in some arteries the process is irregular. CAC asymmetry is most marked when one of the posterior cerebral arteries arises from the internal carotid artery.


Isolation of Arcanobacterium haemolyticum from patients with pharyngitis in Belgium. During a 40 months period, 49 Arcanobacterium haemolyticum strains were isolated from 12,000 throat swabs of patients with pharyngitis originating from 5 belgian provinces. All strains were recovered on sheep blood Columbia agar plates, supplemented by nalidixic acid and colistin. In two thirds of the cases, pharyngitis was associated with a rash. Half of the cases occurred in the age group between 10 and 20 years and isolates were twice more frequent in females than in males. Streptococcus pyogenes was isolated 23.2 times more frequently than Arcanobacterium haemolyticum.


[Regeneration of the ulnar nerve under different blood supply conditions]. As the result of examination of 43 patients with injury to the ulna neurovascular bundle the author studied the regeneration of the ulnar nerve in and without reconstruction of the ulnar artery. The outcomes of ulnar nerve autoplasty are better in restoration of the artery than in application of an epineural suture. Sensitivity and tissue trophies increase essentially, the strength of the hand muscles increases to a lesser degree. Reconstruction of the ulnar artery has the best effect on regeneration of the nerve injured on the forearm and above its ramification on the palm. An important factor is early increase of blood supply and oxygenation, which promotes trophics of the graft, and perfusion of the intergrowiny axons and the surrounding tissues.


Quality control in haemostasis.

Quality control in haemostasis. Laboratory investigation of the haemostatic system deserves particular procedures in the quality control of analytical variables as well as preanalytical variables. This paper reviews the precautions that have to be taken in the blood prelevement, the transport of the tubes and the performance of the laboratory tests aimed to investigate the haemostatic system in order to obtain reliable results.


[Hypothalamic hypopituitarism with hyperphagia and subacute dementia due to neurosarcoidosis: case report and literature review]. The frequency of neurologic involvement in sarcoidosis is about 5%. When the clinical picture presents with only neurological manifestations, as it did in our patient, the diagnosis at presentation is often difficult. Involvement of other tissues must therefore be actively searched. We describe a case of neurosarcoidosis, presenting with hypothalamic hypopituitarism, progressive loss of visual fields, subacute dementia and hypothalamic hyperphagia. The disease very well responded to high dose corticosteroids. The pathology, diagnostic procedures, prognosis and treatment of neurosarcoidosis are discussed.


[The clinical characteristics and diagnosis of lesions of the upper third of the vertebral arteries]. An analysis of the clinical symptoms of abnormalities in the upper third vertebral arteries made it possible to identify 4 stages of their development. The tunnel-compression syndrome was found to underline the abnormalities. It was established that Doppler ultrasonic imaging and vein spondylography were the most informative diagnostic techniques.


[Obesity: danger for the hepatocytes?].

[Obesity: danger for the hepatocytes?]. Obesity is associated either with hepatic steatosis, a well known and innocuous entity or with non alcoholic steatohepatitis. This latter lesion has been recently individualized. It affects mainly middle-aged, obese women, with diabetes and/or hyperlipidaemia. It is morphologically very similar to alcoholic hepatitis. We review the literature considering 1) histologic hepatic lesions of the obese, 2) epidemiologic, clinical and biological characteristics of the non alcoholic steatohepatitis, 3) evolution and treatment of the non alcoholic steatohepatitis and 4) present physiopathological considerations. We conclude by considering the clinician's attitude in front of an obese potentially afflicted by a non alcoholic steatohepatitis.


[An analysis of the level and bilateralness of disorders of the brain stem auditory evoked potential in tumors of the posterior cranial fossa with different locations]. The method of stem auditory evoked potential was used in the examination of 39 patients with tumors of the posterior cranial fossa of various localization. The time indices of the response were analysed: the peak latency of components I, III, and V and interpeak I-III, III-V, and I-V intervals. The most coarse disorders were revealed in patients with tumors of the cerebellopontile angle (100% of cases), which were clearly lateralized. Changes of stem auditory evoked potential in patients with cerebellar tumors were encountered somewhat less frequently (in up to 90%) and the response was asymmetric in most cases. As compared to the first group, however, a high percentage of disorders of component V to stimulation of the intact side was noted. Among patients with median localization of the tumor (vermis cerebelli, floor of fourth ventricle) changes were found in 62% of cases (component V). No authentic differences to stimulation of different sides were revealed. The authors discuss problems on the levels of occurrence of disorders of stem auditory evoked potential in patients with lesions of posterior cranial fossa structures.


[Renal functional reserve].

[Renal functional reserve]. The concept of renal functional reserve (RFR) was introduced in the 80's. The renal functional reserve was defined as the ability of the kidney to increase Renal Plasma Flow (RPF) and Glomerular Filtration Rate (GFR) after a stimulus as a protein load. The absence of RFR defines a state of hyperfiltration which seems to be a detrimental factor for the progression of renal failure. The measure of RFR by a protein load test is thus a mean to detect glomerular hyperfiltration and allows to give adequate diet prescription.


[Electroencephalogram dynamics in Matas' compression test as a criterion of the efficacy of reconstructive operations on the vessels of the carotid basin]. EEG recording with Matas' compression test makes it possible to specify the immediate contribution of the carotid artery to the activity of the cerebral cortex neurons. This supplements the quantitative study of the linear and volume blood flow in the carotid bed. The positive result in compression of the carotid artery is characterized by a stereotype reconstruction of the brain biopotentials on the EEG reflecting the beginning of nerve cell hypoxia. Change of the EEG response in Matas' test after reconstructive operations--endarterectomy of the carotid artery and formation of extra-intracranial microvascular anastomosis--points to the contribution of the carotid artery to the general cerebral blood flow under the new conditions. It is noted that the significance of the newly formed vascular bed in the cerebral blood supply increases gradually and individually in different patients. This is evidently determined by the differences in the severity and spread of atherosclerosis of the cerebral vessels, the arterial pressure level in various vascular beds of the brain, the degree of development of anastomoses and synangioses between the branches of the internal and external carotid arteries, etc.


[Relationship between the hippocampal formation and the cortical and subcortical regions]. A summary of afferent and efferent connections of the hippocampal formation has been reviewed, especially outputs from the subicular complex. The hippocampal formation receives much information from widely spread cortical and subcortical regions, and in turn projects principally to many of the cortical regions. Particularly, the entorhinal area of primates receives a large number of outputs from cortical regions containing the prefrontal, insular, temporal, parietal, cingular, and retrosplenial regions. On the other hand, the cortex of both rodents and primates projects to almost all of the cortical mantle, especially to the prefrontal, piriform, temporal, olfactory relating cortical regions, and to the hippocampal formation itself. Thus, it has been strongly suggested that this structure may function in the modulation of memory and learning. However, many of the differences in species and much of topographical heterogeneity have been indicated in the projectional patterns and regions, from the hippocampal formation. For instance, besides the histochemical heterogeneity of the hippocampal formation, each of the dorsal and ventral parts of constituents of the subicular complex and CA1 undoubtedly have different connections with the cortical regions including the entorhinal and cingulate areas, and with subcortical regions including the anterior thalamic nucleus, nucleus accumbens and mamillary nucleus. Therefore, it could simply be presumed that each of these constituents might work in different aspects of the hippocampal functions. These facts suggest to us that the hippocampal formation, in particular the subicular complex, might have plural characteristics in transferring neural information. Moreover, the distinct dissimilarities of neural connections between rodents and primates indicate that the rodent's hippocampal formation might somehow have an undeveloped neural system of memory, or a different memory system from that of primates.


Pituitary adenomas: tumor cell growth by cluster formation. Pattern analysis based on immunohistochemistry. The topographical distribution of adrenocorticotropic hormone, growth hormone and prolactin was studied in nine multihormonal pituitary adenomas and two normal adenohypophyses using quantitative immunohistochemical methods. For each pituitary hormone paraffin sections stained by antihormone antibodies were scanned with a light microscope equipped with a projection and scanning device. The number of immunoreactive cells of each square in the grid was counted and transformed into pseudocolors. In this way, the distribution of each hormone was documented. A chi-square test was applied to these distribution patterns to prove randomness. A nonrandom distribution of immunoreactive cells was observed in all pituitary adenomas and normal pituitary glands. Cluster formations of immunoreactive cells were found for each hormone. The clusters were surrounded by halo-like areas of decreasing number of immunoreactive cells from center to periphery. The cluster-halo type of immunoreactive cells was found not only in the adenomas but also in the normal pituitary gland. This may be explained by the similarity of biological processes during cell proliferation either in normal development or in adenoma formation. It can be concluded from our studies that pituitary adenomas in most cases develop by multicentric but not diffuse proliferation of cell clones of different endocrine activity.


[Localization of Na/K ATP-ase in the inner ear]. The perilymphatic compartment of the inner ear resembles plasma ultrafiltrate, whereas the endolymphatic compartment is characterized by a high potassium and low sodium concentration. Perilymph is considered to be the precursor of endolymph. The chemical composition of endolymph and the generation of the transepithelial potential is regulated by Na-K-activated adenosine triphosphatase. The cytochemical localization of Na/K ATP-ase is demonstrated in the guinea pig inner ear. The mechanism for cation regulation in the endolymphatic compartment is discussed.


Correlation of neuromuscular pathology in acquired immune deficiency syndrome patients with cytomegalovirus infection and zidovudine treatment. Peripheral nerve and skeletal muscle specimens from 115 autopsied adult AIDS patients were examined for types and incidence of histological abnormalities. Focal perivascular chronic inflammatory infiltrates featuring plasma cells were found in 85% of nerve and muscle specimens. These foci were specifically associated with cytomegalovirus (CMV)-infected capillary or venous endothelial cells in neuromuscular specimens of 31/115 patients, with increasing incidence in patients surviving longer with the diagnosis of AIDS. Neuromuscular CMV was identified histologically in 19% of AIDS patients with an AIDS-defining illness for 3 months or less, with the incidence increasing to 46% of patients who had the diagnosis for 2 years or longer. Vascular damage from CMV endothelial infection may result in regional ischemic and/or inflammatory damage to nerves, producing myelinated fiber loss and axonal degeneration, leading to denervation atrophy of myofibers found in skeletal muscle specimens in a majority of the patients. Myelinated fiber loss within the sural nerve was determined by morphometric quantitation for a subset of 50 patients, and correlated with the presence of histologically identifiable neuromuscular CMV, clinical history of zidovudine administration, and chemotherapy for alleviation of Kaposi's sarcoma. CMV infection and zidovudine treatment were both positively correlated with myelinated fiber loss, while Kaposi's sarcoma chemotherapy did not independently increase the incidence of myelinated fiber loss.


Modulation of kinin responses in human synovium by interleukin-1. Bradykinin (BK) is a weak stimulus for prostaglandin E2 (PGE2) release in untreated human synovial cells, but a potent stimulus in interleukin-1 (IL-1) pretreated cells. The mechanism(s) by which IL-1 induces responsiveness of synovial cells to BK appears to be multifactorial. IL-1 not only upregulates the number of kinin receptors on these cells, but may also upregulate a calcium-dependent process involved in the synthesis of prostaglandins.


Signal transduction pathways of BK2 receptor in the renal glomerulus and mesangial cells: a mini review. Using binding techniques we identified specific B2 kinin binding sites showing a pharmacological profile similar in glomeruli and in mesangial cell. Scatchard analysis revealed two classes of binding sites: a very-high-affinity site (Kd = 0.44 nM) and a high affinity site (Kd = 6.3 nM). Activation of the BK receptor of mesangial cells is associated with i) a transient dose-dependent increase in inositol 1,4,5 Triphosphate, ii) a biphasic rise in cytosolic free calcium, iii) a progressive secretion of PGE2, iv) an inhibition of the PGE2-stimulated increase of cAMP formation. All these effects were prevented by B2 antagonists. This multiple signal transduction pathway could suggest either heterogeneity in the BK receptor of the mesangial cell or different biological responses to be identified. Taken together, the results indicate that BK, at least in cultured cells, acts as a contractile effector, however, the physiological significance of a kinin receptor in the glomerulus remains to be elucidated.


On the role of bradykinin in secretion from vascular endothelial cells. Bradykinin will induce, in perfused rat hindlegs, the acute release from endothelial cells of tissue-type plasminogen activator and of von Willebrand factor. This release is mediated by B2-receptors, requires the influx of extracellular calcium, and is modulated by cyclic nucleotides. A possible role of bradykinin in the physiological regulation of plasma levels of tissue-type plasminogen activator is discussed.


Urinary coagulation-fibrinolysis, kallirein-kinin systems and kininase in cases of preclampsia. Urinary kallikrein and kallikrein activity significantly decreased in cases of preeclampsia (u-kall./CRE.index 42.39 +/- 9.66 ng/mg, u-kall. act./CRE.index 0.26 +/- 0.06 ng/min/mg), and urinary kininase II and kininase activity significantly increased (u-kininase/CRE.index 10.91 +/- 1.26 x 10(-3) IU/min/mg, u-kininase act./CRE.index 506.37 +/- 178.45 pg/min/mg) when compared with those of normal gravidas from 28 weeks to 42 weeks of gestation (u-kall./CRE.index 189.31 +/- 14.17 ng/mg, u-kall. act./CRE index 1.08 +/- 0.10 ng/min/mg, u-kininase/CRE.index 6.24 +/- 0.31 x 10(-3) IU/min/mg, u-kininase act./CRE.index 15.64 +/- 0.10 pg/min/mg). Urinary FPA, B beta 5-42, alpha 2-PI, and alpha 2PI-plasmin-complex (PIC) significantly increased in preeclampsia (u-FPA/CRE.index 23.59 +/- 8.47 ng/mg, u-B beta/CRE.index 105.26 +/- 29.30 ng/mg, u-alpha 2PI/CRE.index 121.53 +/- 43.57 ng/mg, u-PIC/CRE index 278.39 +/- 60.50 ng/mg) when compared with those of normal control group (u-FPA/CRE.index 0.92 +/- 0.04 ng/mg, u-B beta/CRE.index 12.15 +/- 0.44 ng/mg, u-alpha 2PI/CRE.index 4.18 +/- 0.33 ng/mg, u-PIC/CRE.index 5.98 +/- 1.15 ng/mg). Urinary urokinase markedly increased and urinary D-dimer was detected in severe cases of preeclampsia (u-UK/CRE.index 58.20 +/- 43.69 ng/mg, u-D-dimer 54.76 +/- 9.89 ng/ml) when compared with those of normal control group. These findings suggest that deficiency in urinary kinin excretion may induce hypertension in addition to the changes of urinary coagulation-fibrinolysis system that represents the occurrence of either the endothelial cell injury in the glomerulus or the renal tulbular damage in mild cases of preeclampsia, eventually resulting in the intra-renal vascular coagulation.


Determination of cathepsins B, H, L and kininogen in breast cancer patients. In 20 matched pairs, an increase of all cathepsins was measured in carcinoma tissue compared with normal tissue of the same breast. On contrary, the mean value for kininogen was almost 2 fold lower than mean value determined in normal cytosols. From all proteins tested, the amount of cathepsin B correlated mostly with the degree of malignancy inside the group of invasive ductal carcinoma (n = 90, p < 0.01).


Electrophysiological approaches to the study of bradykinin and nitric oxide in inflammatory pain. These electrophysiological studies, using desensitization and selective antagonists, demonstrate a peripheral role of bradykinin in the generation of pain in the rat. In addition, nitric oxide is shown to play a complex role in peripheral and spinal events in nociception.


Contrasting properties of bradykinin receptor subtypes mediating contractions of the rabbit and pig isolated iris sphincter pupillae preparation. Bradykinin contracts both the pig and rabbit iris sphincter preparations. In the pig, the bradykinin antagonists Lys,Lys-[Hyp3, Thi5,8,D-Phe7]-BK and D-Arg-[Hyp3,Thi5,D-Tic7,Oic8]-BK (HOE140) inhibited responses with pKB estimates of 6.0 and 8.4, respectively. These affinities are markedly lower than in the rabbit preparation, suggesting that different receptors are present in each of the two species.


Characterization of a kallidin receptor in the eel intestine. Edman degradation of an eel bradykinin (BK) -like peptide isolated and detected by gel filtration and HPLC and RIA gave an amino acid sequence of Arg1-Pro-Pro-Gly-X-Ser-Pro-Leu-Arg9. Kallidin but not BK and des-Arg9-BK contracted eel intestine. The contractile effect of kallidin was not decreased by B1 and B2 receptor antagonists (up to 10(-6)M), nor by anticholinergics, antiadrenergics, ganglion blockers and an angiotensin II receptor antagonist but was attenuated by 10(-5)M indomethacin. Kallidin appears to interact with a receptor different from the BK B1 and B2 receptor types and prostaglandins may participate in the response.


Characterization of two different affinity B2-kinin binding sites in rat glomeruli. We have recently characterized a bradykinin (BK) receptor in rat renal mesangial cells (1). Activation of this receptor is associated with PGE2 release and IP3 formation suggesting involvement in cell contraction which can be linked to the control of the glomerular filtration rate (2). Whether this mesangial BK receptor is the unique glomerular BK receptor remains to be elucidated. In an attempt to answer to this question, we performed binding studies using decapsulated isolated glomeruli. Scatchard analysis of the binding data obtained with this preparation revealed the presence of two distinct B2-kinin binding sites. However, a consistent difference was observed in both the affinity and the density. We further investigated the pharmacological binding profile after an initial step of solubilization. Several experiments were performed to establish optimal conditions of solubilization. For this, different detergents such as Triton X-100, CHAPS and n-octyl beta-D glucopyranoside were tested at various concentrations, durations and temperatures of incubation. The binding was performed with two different [125I]-Tyr0-BK concentrations (0.5 and 7 nM) with either untreated decapsulated glomeruli or solubilized preparation for 45 minutes at +4 degrees C in the binding buffer containing a mixture of protease inhibitors. The greatest binding was achieved after treating glomeruli with 25 mM n-octyl beta-D glucopyranoside for 60 minutes at +4 degrees C under constant shaking. Two B2-kinin receptors of different affinities were detected. The same binding characteristics were obtained both in the 12,000 x g and 100,000 x g supernatant.(ABSTRACT TRUNCATED AT 250 WORDS)


Mechanism of the relaxant response of the rat duodenum to bradykinin. Bradykinin (BK) did not increase cyclic AMP production in cultured rat duodenum smooth muscle cells. Its relaxant effect on the tissue was inhibited by apamin and potentiated by phorbol dibutyrate (PDBU). PDBU also caused a relaxation which was inhibited by apamin. BK's relaxant effect, and its potentiation by PDBU, are due to activation of Ca(2+)-dependent K+ channels.


DesArg10[Hoe 140] is a potent B1 bradykinin antagonist. DesArg10[Hoe 140] and Des(D-Arg1, Arg10)[Hoe 140], desArg10-analogs of the potent and stable B2 bradykinin (BK) receptor antagonist Hoe 140 were found to be potent and stable antagonists of the B1 receptor in vitro and in vivo. They were, however, less selective than DesArg9[Leu8]BK, the metabolically unstable B1 prototype antagonist. Surprisingly, Hoe 140, which behaved as a pure B2 antagonist in several smooth muscle preparations, had a considerable inhibitory effect against the B1 agonist DesArg9-BK in bovine aortic endothelial cells. This finding for the first time suggests that B1 receptors are heterogenous.


Kinin contribution to chronic antihypertensive actions of ACE-inhibitors in hypertensive rats. The contribution of endogenous bradykinin to the chronic antihypertensive actions of the ACE-inhibitor, ramipril, was investigated in 2-kidney 1 clip (2K1C) hypertensive kinin-deficient Brown Norway Katholieke rats (BN-K) and 2K1C hypertensive Wistar rats (WI) as well as in spontaneously hypertensive rats (SHR). Treatment with ramipril plus the BK B2-receptor antagonist HOE 140 for 6 weeks significantly attenuated the antihypertensive effects of the ACE-inhibitor in 2K1C hypertensive WI rats, but not in 2K1C hypertensive BN-K rats and in SHR. Our data support the hypothesis that potentiation of endogenous kinins contributes to the chronic antihypertensive actions of ACE-inhibitors in experimental renal hypertension. Whether this holds also true for other forms of hypertension remains to be answered.


Cardiac angiotensin converting enzyme and diastolic function of the heart. It has been known for a long time that systemic infusion of angiotensin II in patients with coronary artery disease or normal control subjects causes a marked increase in left ventricular end diastolic pressure (LVEDP) and systolic pressure (LVP) (1,2). In this setting angiotensin II produces a marked increase in afterload that makes it difficult to acknowledge possible local myocardial effects of the peptide. The studies (3-8) summarized in the present paper were designed to examine the physiological role of local cardiac angiotensin II generation and local bradykinin degradation on cardiac function in the normal and hypertrophied rat heart. Angiotensin I and angiotensin II, infused in isolated, well oxygenated, buffer perfused normal rat hearts, produced a mild increase in LVEDP with no change in systolic function (3). In contrast, in hypertrophied rat hearts, angiotensin I and angiotensin II caused a marked deterioration of diastolic function, increasing LVEDP from 10 to 25-37 mmHg on average (3,5). Preliminary evidence suggests that angiotensin II effects on diastolic function are mediated via a protein kinase C dependent pathway that might involve Na+/H+ exchange (4,5). When cardiac angiotensin converting enzyme was blocked by infusion of an ACE inhibitor prior and in parallel to angiotensin I infusion no changes in diastolic function were noted (6). Furthermore, ACE inhibition blunted the diastolic dysfunction during low flow ischemia in isolated hypertrophied rat hearts (7). This effect of ACE inhibition was even more remarkeable, since no exogenous angiotensin was infused in this experiment.(ABSTRACT TRUNCATED AT 250 WORDS)


[Ca2+]i effects of bradykinin B2 receptor activation in PC12 cells. In PC12 cells, activation of B2 receptors by bradykinin promotes an elevation of cytosolic Ca2+ by two mechanisms: IP3 mediated release of Ca2+ from intracellular stores and stimulation of multiple Ca2+ influx pathways. Since these events can have different kinetics and spatial localizations they can induce diversified effects in different cell areas.


Bradykinin suppresses endothelin-induced contraction of coronary, renal and femoral arteries through its B2-receptor on the endothelium. Effect of bradykinin (BK) on endothelin-1 (ET-1)-induced vasoconstriction and its mechanism were investigated. The development of isometric force of arterial rings of canine coronary, renal and femoral arteries was recorded using a organ bath containing Krebs-Henseleit buffer aerated with 95% O2 and 5% CO2. ET-1 at more than 10(-9) M dose-dependently induced vascular contraction similarly among the three arteries. BK at more than 10(-8) M dose-dependently suppressed the ET-1-induced vasoconstriction only in the presence of endothelium, and the effect of BK was largest in the coronary arteries. The BK-induced suppression was not affected by addition of des-Arg9-[Leu8]-BK, an antagonist for B1-receptor, but did be completely reversed by addition of B2-receptor antagonist (10(-6) M) [D-Arg0,Hyp3,Thi5,8,D-Phe7]-BK. The BK's suppression of the ET-1-induced vasoconstriction was partly reversed by additions of each 10(-5) of Ng-nitro-L-arginine, a substrate inhibitor of nitric oxide, methylene blue, an inhibitor of soluble guanylate cyclase, or indomethacin, an inhibitor of cyclooxygenase. The reversing effects of methylene blue and indomethacin were additive. BK suppresses the ET-1-induced vasoconstriction through B2-receptor on the endothelium. Both endothelial nitric oxide and prostaglandin(s) are participated in the BK's effect.


Regional hemodynamic effects of a kinin antagonist in awake normotensive rats. We evaluated the effects of the B2-receptor antagonist Ac-D-Arg[Hyp3,D-Phe7,Leu8]-bradykinin on mean blood pressure (MBP) and Doppler mesenteric blood flow (DMBF). The antagonist, at a dose able to completely block the hemodynamic effects of exogenous bradykinin, increased MBP by 3 +/- 1% and decreased DMBF by 12 +/- 3%. These responses persisted after pharmacological neuro-hormonal blockade. Our results suggest that the kallikrein-kinin system plays a role in the regulation of mesenteric blood flow in rats.


Effects of converting enzyme inhibition on endothelial bradykinin metabolism and endothelium-dependent vascular relaxation. The effects of ACE-inhibitors on bradykinin metabolism and bradykinin-induced endothelium-dependent relaxation were studied in isolated coronary arteries and endothelial cells in culture. The results suggest that ACE-inhibitors affect coronary vascular tone by at least two endothelium-dependent and bradykinin-mediated mechanisms: First, ACE-inhibitors decrease endothelial bradykinin degredation which is accompanied by an augmented bradykinin mediated endothelium-dependent relaxation. Second, ACE-inhibitors evoke endothelium-dependent relaxations in coronary arteries stimulated with threshold concentrations of bradykinin, which cannot be attributed to an inhibition of bradykinin degradation. The effect appears to represent a new mechanism which may be based on an interaction of the bradykinin receptor and the angiotensin converting enzyme on the cellular level.


Converting enzyme inhibitor-stimulated formation of nitric oxide and prostacyclin in endothelial cells from bovine aorta is mediated by endothelium-derived bradykinin. Like bradykinin the converting enzyme inhibitor ramiprilat concentration-dependently enhances the formation of nitric oxide and prostacyclin assessed by intracellular cyclic GMP accumulation and 6-keto prostaglandin F1. resp. Both ramiprilat-induced effects are completely suppressed by the specific kinin receptor antagonist Hoe 140. The ramiprilat-induced cyclic GMP increase is totally blocked by the stereospecific inhibitor of nitric oxide synthase, NG-nitro-L-arginine.


Ramiprilat prevents PAF-induced myocellular and endothelial injury in a neutrophil-perfused heart preparation. This study investigates the action of PAF-stimulated human polymorphonuclear leukocytes (PMN) on myocardial integrity and function in Langendorff-perfused guinea-pig hearts. Infusion of 10(6) PMN/ml resulted in a negative inotropic effect without larger biochemical evidence for myocardial tissue injury while infusion of PAF (1 microM) did not cause any permanent effect at all. However, the combined administration of PAF-stimulated PMN resulted in severely depressed myocardial contractile function and biochemical evidence for myocardial tissue injury. This was probably due to an enhanced uptake of PMN from the coronary perfusate and accumulation within the myocardial tissue. Ramiprilat, (10 microM) significantly improved left ventricular function and myocardial cell integrity. Similar results were obtained with bradykinin (1 nM). The data suggest a PAF-induced, PMN-mediated myocardial tissue injury as well as cardioprotective actions of ACE inhibition which are possibly related to stimulation of the kinin/prostacyclin axis.


Kininogenase activity of rSMT3, a rat submandibular gland tonin. rSMT3, a tonin like angiotensin II generating enzyme present in rSMG presents a potent oxytocic effect on the isolated rat uterus, which was blocked by a B2 bradykinin receptor antagonist. Under optimal conditions of pH, rSMT3 liberates kinin at rate 19-fold greater than angiotensin II.


Kallikrein-kinin,enkephalin, renin-aldosterone and catecholamine systems in the vanadate (as vanadyl)-induced arterial hypertension. Exposure to vanadate was found to induce arterial hypertension through effects on renin-angiotensin-aldosterone, renal peptidergic, and central and peripheral catecholaminergic systems. Vanadate increased, mainly in vascular myocells, both receptor-operated Ca2+ channel- and cyclic-AMP-dependent availability of Ca2+ for contractile processes. Vanadate was selectively accumulated by tissues in the +4 oxidation state (vanadyl).


Influence of a kinin antagonist on acute hypotensive responses induced by bradykinin and captopril in spontaneously hypertensive rats. We have evaluated the effects of a B2 receptor antagonist (B5630) of kinins on BK and captopril-induced acute hypotensive responses in anaesthetized SHR. Intravenous treatment of BK (1.0 microgram) and captopril (0.3 mg/kg) caused significant (p < 0.05) fall in the SBP and DBP. Whereas BK caused greater fall in the SBP (p < 0.05), DBP (p < 0.01) and duration of hypotension (p < 0.05) when administered after captopril (Fig 1 and 2). All the hypotensive effects of BK and captopril were significantly antagonised (p < 0.05) in the presence of B5630 (2.0 mg/kg). Further, the duration of hypotensive responses of BK and captopril were blocked (p < 0.05) by B5630. The agonists and BK-antagonist did not cause significant (p > 0.05) alterations in HR during the entire investigation. These findings provide evidence to support the suggestion that B2 receptor might be involved in the regulation of the hypotensive actions of BK and captopril. Kinins should also have valuable functions in the antihypertensive property of captopril-like drugs.


Angiotensin converting enzymes from urine of treated and untreated essential mild hypertensive patients (EHP) with diuretic: partial purification and characterization. Urine of untreated EHP was eluted, on a ion-exchange chromatography, in two protein peaks with ACE activity, at 0.7 mS (BI) and 1.25 mS (BII), while urine of treated EHP, was eluted only in one peak with ACE activity (0.7 mS). BI (Mr, 88 kDa) and BII (Mr, 61 kDa) convert AI to AII, hydrolyze bradikinin, are inhibited by captopril, EDTA and metal ions.


Components of plasma and tissue kallikrein-kinin system in the urine of patients with latent, nephrotic and hypertonic forms of glomerulonephritis. Activities of main components of KKS were estimated in the urine of patients with latent, nephrotic and hypertonic forms of chronic glomerulonephritis (ChGN) and compared to those parameters in urine of healthy persons. The data obtained allow to make a conclusion concerning the pathogenetic and the compensatory role of plasma KKS in the nephrotic form of ChGN.


Tissue kallikrein-kinin system in the brain and the regulation of arterial pressure. The intracerebral administration of kininase inhibitors produced an increase in arterial pressure of the SHR but not in normotensive animals. The SHR were several fold more sensitive to the pressor response elicited by the intracerebral injection of bradykinin, however SHR with low blood pressure showed decreased sensitivity to the bradykinin pressor effect. The results suggest that an endogenous kinin system plays a role in the central regulation of blood pressure of the SHR.


Involvement of the kinin-forming system in the physiopathology of rheumatoid inflammation. Kinins are potent mediators of rheumatoid inflammation. The components of the kinin-forming system are hyperactive in RA. Excessive release of kinins in the synovial fluid can produce oedema, pain and loss of functions due to activation of B1 and B2 receptors. These receptors could be stimulated via injury, trauma, coagulation pathways (Hageman factor and thrombin) and immune complexes. The activated B1 and B2 receptors might cause release of other powerful non-cytokines and cytokines mediators of inflammation, for example, PGE2, PGI2, LTs, histamine, PAF, IL-1 and TNF derived mainly from polymorphonuclear leukocytes, macrophages, endothelial cells and synovial tissue. These mediators are capable of inducing bone and cartilage damage, hypertrophic synovitis, vessels proliferation, inflammatory cells migration, and possibly angiogenesis in pannus formation. These pathological changes, however, are not yet defined in human model of chronic inflammation (RA). Hence, the role of kinin and its interacting inflammatory mediators would soon start to clarify the detailed questions they revealed in clinical and experimental models of chronic inflammatory joint diseases. Several B1 and B2 receptor antagonists are being synthesized in an attempt to study the molecular functions of kinins in inflammatory processes (RA, periodontitis and osteomyelitis), and they represent and important area for continued research in rheumatology. Future development of specific, potent and stable B1 and B2 receptor antagonists or combined B1 and B2 antagonists with y-IFN might serve as pharmacological basis of more effective rationally-based therapies for RA. This may lead to significant advances in our knowledge of the mechanisms and therapeutics of rheumatic diseases.


Kinin receptors on asthmatic airways: functional subtyping. Bradykinin, kallidin and [desArg9]-bradykinin are oligopeptides that may contribute as mediators in the pathogenesis of bronchial asthma by interacting with specific cell surface receptors. The structure-activity relationship of kinins within the lower airways has been investigated in 16 asthmatic subjects. The findings of the present study suggest a complex action of kinins on asthmatic airways probably involving more than one receptor subtype.


Lack of specific binding of bradykinin and D-Arg [Hyp3, Thi5, D-Tic, Oic8] bradykinin in membranes from rat heart. Recent data demonstrated effects of bradykinin (BK) in the isolated perfused rat heart which could be blocked by BK antagonists. However, so far BK receptors in heart tissue have not been characterized. To search for BK receptors in rat hearts iodinated D-Arg[Hyp3,Thi5,D-Tic,Oic8]BK (Hoe 140) was used as a ligand for binding due to its high affinity and to its resistance to degradation. The labeled antagonist bound well to membranes prepared from rat ileum and could be displaced by the unlabeled antagonist as well as by BK and T-kinin in a concentration dependent manner. However, there was no specific binding detectable when membranes from rat left cardiac ventricle were used. To assure integrity of at least one other receptor in these membranes, binding of 3H-methylscopolamine and its displacement by the respective cold ligand was demonstrated. To rule out an occupation of the BK receptors by endogenous formed BK, the tissue was treated with an acidic buffer with high ionic strength to remove surface bound BK. However, this treatment did not unmask any specific binding for the BK antagonist. In view of the possibility that the structure of the labeled antagonist prevented its binding, experiments were carried out using tritiated BK itself. These experiments also failed to demonstrate specific binding sites which indicate that the structural aspects of Hoe 140 are probably not interfering in binding of the antagonist, especially since it binds to ileum. It is concluded, that there are too few binding sites for BK in the rat heart homogenate for ordinary binding studies.(ABSTRACT TRUNCATED AT 250 WORDS)


Fatal disseminated Conidiobolus coronatus infection in a renal transplant patient. A case of fatal disseminated fungal infection due to Conidiobolus coronatus in a patient with a renal transplant is described. This organism, known to cause localized infections in otherwise healthy individuals in the tropics, is now recognized as a cause of fatal infection in immunosuppressed hosts. Histologically, localized infections are characterized by lack of vessel invasion and the presence of an eosinophilic sleeve around fungal elements, called the Splendore-Hoeppli phenomenon. The histologic findings in the present case were more typical of mucormycosis, and the correct diagnosis was established only after the organism was isolated and identified in culture.


DNA content and proliferative activity in ovarian small cell carcinomas of the hypercalcemic type. Implications for diagnosis, prognosis, and histogenesis. Ovarian small cell carcinoma of the hypercalcemic type is a rare cancer of young women of nuclear histogenesis. Although usually lethal, a subset of patients with stage I tumors have survived. Twenty-five cases of small cell carcinoma (17 stage I, 1 stage II, and 7 stage III) were evaluated by flow cytometric analysis performed on paraffin-embedded tissue. Forty classifiable histograms from 23 cases were DNA diploid; histograms from two cases could not be interpreted. The mean S-phase fraction was 10.5% (4.7% to 18.4%), and the mean G2/M fraction was 5% (1.5% to 19.5%) in 22 cases. Mean values of mitotic rate, S-phase fraction, G2/M fraction, and proliferation index (%S + %G2/M) were not associated with stage or outcome, nor did any proliferation variable correlate with interval to death. A comparative review of flow cytometric findings in other types of ovarian cancer that may be confused with small cell carcinoma indicates that flow cytometry is an objective diagnostic aid to distinguish small cell carcinoma of the hypercalcemic type from other forms of small cell carcinoma, malignant germ cell tumors, and sex-cord tumors, and that small cell carcinoma probably does not belong in either the surface epithelial or germ cell categories of ovarian cancer. Finally, the flow cytometric findings in this report exemplify the rare phenomenon of a diploid DNA content in a very lethal tumor and indicate that an accurate diagnosis of tumor type is essential before a prognosis on the basis of flow cytometric data can be made.


Malignant adenomyoepithelioma of the breast. An immunohistochemical, cytophotometric, and ultrastructural study of a case with lung metastases. Adenomyoepithelioma of the breast is a rare tumor that, on the basis of histologic, immunohistochemical, and ultrastructural features, has a bicellular pattern of epithelial and myoepithelial cells regularly distributed in tubular structures. Until now, this tumor was thought to be a benign or low-grade malignant lesion because of possible local recurrences (7 recurrent cases of 60 in the literature). Only one of these cases had nodal involvement, thereby suggesting the possible malignancy of this lesion. This paper reports the first documented case of malignant adenomyoepithelioma with lung metastases presenting the same biphasic pattern as the primary tumor.


Persistent hepatitis B virus infection and hepatoma in The Gambia, west Africa. A case-control study of 140 adults and their 603 family contacts. To determine the incidence of persistent hepatitis B virus infection and its etiologic role as a cause of hepatoma, the authors carried out a case-control investigation of 70 persons with hepatoma, 70 controls, and their families in 1981-1982 in The Gambia, West Africa. The risk of developing hepatoma after the age of 39 years was 1.4% in men and 0.3% in women. Hepatoma occurred more than twice as frequently among persons who had four or more older siblings as among persons who had less than two older siblings. The attributable risk between persistent infection with hepatitis B virus and hepatoma was 78% for individuals aged less than 50 years and 37% for persons aged 50 years or more, with an overall risk of 53%. The high prevalence of hepatitis B surface antigen and hepatitis B e antigen antigenemia in children under 15 years of age (14% of 341 children) and the positive correlation between late birth order and risk of developing hepatoma suggest that postnatal early childhood exposure to hepatitis B virus is an important risk factor. The use of a hepatitis B virus vaccine which provides durable immunity in very young children will probably prevent most cases of hepatoma.


Age at first establishment of chronic hepatitis B virus infection and hepatocellular carcinoma risk. A birth order study. It is frequently assumed that the risk of hepatocellular carcinoma related to hepatitis B virus is higher when chronic hepatitis B virus infection is acquired early in life. This hypothesis has never been directly evaluated. However, firstborn and secondborn children are exposed to common infections after their school enrollment, whereas laterborn children are exposed much earlier, through their older siblings. The authors analyzed sibship size and birth order data from a large case-control study of patients admitted to Athens, Greece, hospitals between April 1976 and October 1984. The analyses included 185 patients with hepatocellular carcinoma, 35 patients with metastatic liver cancer, and 432 other hospital controls. There was a tendency for cases of hepatocellular carcinoma to concentrate at higher birth orders. When the analysis was restricted to cases and controls who were positive for hepatitis B surface antigen, this tendency was even more notable. These results are compatible with the hypothesis that establishment of chronic hepatitis B virus infection at an early age increases the risk of hepatocellular carcinoma substantially more than does chronic infection with this virus established at a later age.


Improved detection of antibodies to hepatitis C virus in dialysis patients using a second-generation enzyme immunoassay. We tested serum samples from 99 patients undergoing maintenance hemodialysis for hepatitis C virus (HCV) antibodies using a first-generation, licensed anti-HCV enzyme immunoassay (EIA) and a second-generation anti-HCV EIA that detect three gene products c100-3, NS3, and core. Specimens that were repeatedly reactive by either or both screening assays were further evaluated by testing with supplemental EIAs and a dot blot immunoassay. There was 87.9% agreement between the licensed HCV EIA and the HCV EIA second generation. HCV EIA Second Generation detected 10 more positive specimens than HCV EIA, for an increase in detection from 33.3% (33/99) to 43.4% (43/99). We conclude that HCV EIA Second Generation improves detection of HCV infection in hemodialysis patients.


Distribution and threshold expression of the tRNA(Lys) mutation in skeletal muscle of patients with myoclonic epilepsy and ragged-red fibers (MERRF). We investigated the distribution and expression of mutant mtDNAs carrying the A-to-G mutation at position 8344 in the tRNA(Lys) gene in the skeletal muscle of four patients with myoclonus epilepsy and ragged-red fibers (MERRF). The proportion of mutant genomes was greater than 80% of total mtDNAs in muscle samples of all patients and was associated with a decrease in the activity of cytochrome c oxidase (COX). The vast majority of myoblasts, cloned from the satellite-cell population in the same muscles, were homoplasmic for the mutation. The overall proportion of mutant mtDNAs in this population was similar to that in differentiated muscle, suggesting that the ratio of mutant to wild-type mtDNAs in skeletal muscle is determined either in the ovum or during early development and changes little with age. Translation of all mtDNA-encoded genes was severely depressed in homoplasmic mutant myoblast clones but not in heteroplasmic or wild-type clones. The threshold for biochemical expression of the mutation was determined in heteroplasmic myotubes formed by fusion of different proportions of mutant and wild-type myoblasts. The magnitude of the decrease in translation in myotubes containing mutant mtDNAs was protein specific. Complex I and IV subunits were more affected than complex V subunits, and there was a rough correlation with both protein size and number of lysine residues. Approximately 15% wild-type mtDNAs restored translation and COX activity to near normal levels. These results show that the A-to-G substitution in tRNA(Lys) is a functionally recessive mutation that can be rescued by intraorganellar complementation with a small proportion of wild-type mtDNAs and explain the steep threshold for expression of the MERRF clinical phenotype.


Submicroscopic deletions at the WAGR locus, revealed by nonradioactive in situ hybridization. Fluorescence in situ hybridization (FISH) with biotin-labeled probes mapping to 11p13 has been used for the molecular analysis of deletions of the WAGR (Wilms tumor, aniridia, genitourinary abnormalities, and mental retardation) locus. We have detected a submicroscopic 11p13 deletion in a child with inherited aniridia who subsequently presented with Wilms tumor in a horseshoe kidney, only revealed at surgery. The mother, who has aniridia, was also found to carry a deletion including both the aniridia candidate gene (AN2) and the Wilms tumor predisposition gene (WT1). This is therefore a rare case of an inherited WAGR deletion. Wilms tumor has so far only been associated with sporadic de novo aniridia cases. We have shown that a cosmid probe for a candidate aniridia gene, homologous to the mouse Pax-6 gene, is deleted in cell lines from aniridia patients with previously characterized deletions at 11p13, while another cosmid marker mapping between two aniridia-associated translocation breakpoints (and hence a second candidate marker) is present on both chromosomes. These results support the Pax-6 homologue as a strong candidate for the AN2 gene. FISH with cosmid probes has proved to be a fast and reliable technique for the molecular analysis of deletions. It can be used with limited amounts of material and has strong potential for clinical applications.


Molecular and genetic analysis of a compound heterozygote for dysprothrombinemia of prothrombin Tokushima and hypoprothrombinemia. The molecular and genetic basis of a compound heterozygote for dys- and hypoprothrombinemia was analyzed. Abnormal nucleotide sequences of the human prothrombin gene were screened by PCR-single-strand conformation polymorphism (PCR-SSCP) with endonuclease digestion and mutated primer-mediated PCR-RFLP. A single nucleotide substitution responsible for dysprothrombinemia of prothrombin Tokushima was detected, as were three polymorphisms. The mutation for hypoprothrombinemia was detected by PCR-single-strand conformation polymorphism (PCR-SSCP) with endonuclease digestion in exon 6, near MboII-RFLP and NcoI-RFLP. Sequencing of PCR-amplified genomic DNA revealed a single base insertion of thymine (T) at position 4177. The resulting frameshift mutation caused both an altered amino acid sequence from codon 114 and a premature termination codon (i.e., TGA) at codon 174 in exon 7. Because exon 7 encodes the kringle 2 domain preceding the thrombin sequence, this frameshift leads to the null prothrombin phenotype. The inheritance of the hypoprothrombinemia gene from the father to the proband was proved by PCR-SSCP with endonuclease digestion and mutated primer-mediated PCR-RFLP.


Genetic and radiation hybrid mapping of the hyperekplexia region on chromosome 5q. Hyperekplexia, or startle disease (STHE), is an autosomal dominant neurologic disorder characterized by muscular rigidity of central nervous system origin, particularly in the neonatal period, and by an exaggerated startle response to sudden, unexpected acoustic or tactile stimuli. STHE responds dramatically to the benzodiazepine drug clonazepam, which acts at gamma-aminobutyric acid type A (GABA-A) receptors. The STHE locus (STHE) was recently assigned to chromosome 5q, on the basis of tight linkage to the colony-stimulating factor 1-receptor (CSF1-R) locus in a single large family. We performed linkage analysis in the original and three additional STHE pedigrees with eight chromosome 5q microsatellite markers and placed several of the most closely linked markers on an existing radiation hybrid (RH) map of the region. The results provide strong evidence for genetic locus homogeneity and assign STHE to a 5.9-cM interval defined by CSF1-R and D5S379, which are separated by an RH map distance of 74 centirays (roughly 2.2-3.7 Mb). Two polymorphic markers (D5S119 and D5S209) lie within this region, but they could not be ordered with respect to STHE. RH mapping eliminated the candidate genes GABRA1 and GABRG2, which encode GABA-A receptor components, by showing that they are telomeric to the target region.


Ocular involvement in an outbreak of herpes gladiatorum. An epidemic of herpes simplex virus type 1 occurred in 60 of 175 wrestlers (34%) attending a four-week intensive training camp. Five of these 60 patients (8%) developed ocular involvement that included follicular conjunctivitis, blepharitis, and phlyctenular disease. Cultures of the conjunctiva and eyelid vesicles were positive for herpes simplex virus type 1 in four of the five patients with ocular disease. The viral isolates were compared by restriction-endonuclease analysis, which disclosed that three of the four isolates were the same strain. None of the patients had corneal involvement and there has been no evidence of viral recurrence to date. Herpes simplex virus type 1 is a health risk for wrestlers, and ocular infections are part of the clinical spectrum. Prompt diagnosis and appropriate management of the outbreak may reduce the severity of the outbreak transmission.


The use of polymerase chain reaction for the detection of chlamydial keratoconjunctivitis. Ocular swabs from 30 consecutive patients with follicular conjunctivitis were screened for Chlamydia trachomatis, herpes simplex virus, and adenovirus by a variety of laboratory techniques. For the detection of C. trachomatis, we compared two polymerase chain reaction methods, McCoy cell culture isolation, and the direct fluorescein-conjugated monoclonal antibody test. Four of 30 patients tested positive for C. trachomatis by using both conventional and biotinylated polymerase chain reaction methods. Two of the four patients were also McCoy cell culture-positive for C. trachomatis and one of four patients tested positive by using a fluorescein-conjugated chlamydial monoclonal antibody test. All four patients responded to oral antibiotic treatment. On follow-up testing, all four patients were polymerase chain reaction-negative, McCoy cell culture-negative, and fluorescein-conjugated antibody test-negative for C. trachomatis. The polymerase chain reaction appears to be an equally specific and more sensitive method than McCoy cell culture or fluorescein-conjugated antibody testing for the detection of C. trachomatis from ocular specimens.


Intravitreal foscarnet for cytomegalovirus retinitis in a patient with acquired immunodeficiency syndrome. We treated a patient who had acquired immunodeficiency syndrome and cytomegalovirus retinitis of the left eye. After anesthetic had been topically administered, the patient received intravitreal injections of 1,200 micrograms of foscarnet. Plasma and vitreous foscarnet levels were measured by high-performance liquid chromatography. Systemic absorption of the drug was not evident. Elimination half-life from the vitreous after one injection was 54.0 hours. Vitreous levels remained above the mean 50% inhibition value for cytomegalovirus for approximately 56 hours and above the mean inhibition value for human immunodeficiency virus for approximately 241 hours. The patient's visual acuity improved from 20/30 to 20/25 in the left eye. Ophthalmoscopy showed the retinal lesion to have become inactive, and no reactivation occurred during the follow-up period of more than four months. The drug was well tolerated and no retinal toxicity was evident. We suggest an induction treatment regimen of two injections weekly for three weeks, followed by a maintenance treatment regimen of one injection weekly.


Lymphoproliferative lesions in patients with common variable immunodeficiency syndrome. We reviewed our experience with 30 nodal and extranodal lymphoid lesions from 17 patients with common variable immunodeficiency (CVID). Immunohistochemical studies were performed on biopsies from 15 patients, in situ hybridization for Epstein-Barr virus in nine cases, and gene rearrangement analysis on seven lesions. The biopsies were classified into four groups: malignant lymphoma (two cases); atypical lymphoid hyperplasia (eight cases); reactive lymphoid hyperplasia (14 cases); and chronic granulomatous inflammation (six cases). The two malignant lymphomas were diagnosed using histologic criteria; tissue was not available for the assessment of clonality. In one neoplasm, Epstein-Barr virus was identified in the tumor cells by in situ hybridization. The cases of reactive lymphoid hyperplasia and chronic granulomatous inflammation had no atypical architectural, cytologic, or immunohistochemical features. The cases of atypical lymphoid hyperplasia were of particular interest, as these patients had either widespread involvement or massive disease. The diagnosis of lymphoma was considered likely by the clinicians and, in three cases, the histologic slides were originally interpreted as malignant lymphoma by the referring pathologists. Although the architecture of these lesions appeared to be effaced on hematoxylin and eosin-stained sections, immunohistochemical analysis demonstrated preserved architecture with florid expansion of B-cell and T-cell compartments. In addition, clinical follow-up of these patients was benign, and gene rearrangement analysis in three lesions revealed no evidence of clonality. We conclude that the majority of lymphoid lesions in patients with CVID are benign. Immunohistochemical and gene rearrangement studies are particularly helpful in the assessment of cases of atypical lymphoid hyperplasia.


Ductal carcinoma in situ of the female breast. Short-term results of a prospective nationwide study. The Danish Breast Cancer Cooperative Group. In a Danish nationwide prospective study of in situ carcinoma of the breast, 112 women with ductal carcinoma in situ, treated with excision only, were registered from 1982 to 1987. Within a median follow-up of 53 months, a crude recurrence rate of 22% (25 cases) was found, of which five cases recurred as invasive carcinomas and 20 cases as in situ carcinomas. The histopathologic review included a single-parameter analysis of histological growth pattern, size of lesion, nuclear size, presence of comedonecrosis, and subhistologic type. A strong interrelationship was found for histological growth pattern, nuclear size, and comedonecrosis. These parameters were also significantly related to recurrence. Cases that had clinical symptoms had a high recurrence rate as compared with cases that were discovered by mammography only or incidentally.


Stage means more than grade in adenoid cystic carcinoma. Our experience with 184 previously untreated patients who had adenoid cystic carcinoma of salivary gland origin is reviewed. Retrospective staging was possible in all but nine patients who had minor salivary gland primary tumors. Sixty-three percent of patients were diagnosed as having stage I or stage II disease (stage I, 64 patients; stage II, 47 patients), whereas 43 and 21 patients had stage III and IV tumors, respectively. Grading was as follows: cribriform pattern only (grade 1, 126 patients; 68%), mixed cribriform and solid features (grade 2, 48 patients; 26%), and solid only (grade 3, 10 patients; 5%). Treatment was predominantly surgical (174 patients), and relatively few patients received adjunctive, postoperative irradiation (27 patients). Cumulative 10-year survival was 75%, 43%, and 15% for stage I, stage II, and stage III and IV patients, respectively, and cause-specific survival at 10 years was as high as 94% in patients with stage I disease. Only the clinical stage had a significant impact on survival. Neither survival, regional metastases (16 patients; 11%), nor distant dissemination (64 patients; 43%) was predictable on the basis of tumor grade alone. The prognosis in patients with early stage lesions may be better than has been appreciated.


Smoking as an etiologic factor in the development of Warthin's tumor of the parotid gland. In order to further examine a preliminary association between smoking and the subsequent development of Warthin's tumor, a case-control study was undertaken between the years 1980 and 1989. Consecutive patients with Warthin's tumor served as cases, and consecutive patients with pleomorphic adenomas served as controls. A positive history of smoking was defined as a patient with greater than a 10-pack year history. There were 28 cases and 69 controls (ratio: 1:2.5). The number of male to female patients with Warthin's tumor and pleomorphic adenoma was 22 to 6 (3.7:1) and 22 to 47 (1:2.1), respectively. The mean age at presentation with Warthin's tumor or pleomorphic adenoma was 60.7 years and 40.7 years, respectively. In those patients for whom a definite smoking history was known (93 patients), an odds ratio of 8.1 (p < 0.001) was calculated. In order to exclude sex as a possible confounder, the odds ratio in males only was 6.4 (p = 0.007). In order to exclude age as a possible confounder, the odds ratio in all patients over 45 years (48 patients) was 11.2 (p < 0.001). In summary, smokers have eight times the risk of developing a Warthin's tumor than nonsmokers. This case-control study suggests that smoking may be one of the etiologic factors associated with this benign salivary gland tumor.


[24 cases of human parvovirus B19 infection in children]. From January 1, 1987 through December 31, 1990, twenty-four pediatric patients with human parvovirus B19 (HPV B19) infection were seen. In every case the diagnosis was established by a positive capture immunoassay for IgM antibodies against the HPV B19. Four patients had hematologic manifestations, including one case of transient bone marrow aplasia revealing hereditary spherocytosis, one case of autoimmune hemolytic anemia with beta-thalassemia, and two cases of peripheral thrombocytopenia. Eight patients had skin lesions, with a morbilliform rash in six cases, erythema nodosum in one case, and Gianotti-Crosti syndrome in one case. No patients had erythema infectiosum. Seven patients developed joint manifestations: Henoch-Schönlein purpura in two cases, arthralgia in four cases, and polyarticular disease progressing to severe rheumatoid arthritis in a thirteen-year-old girl. Unremarkable symptoms of viral disease were seen in three patients. A five-month-old infant developed severe acute myocarditis. One patient with hepatitis A had acute liver failure. This study confirms the broad spectrum of clinical manifestations of HPV B19 infection. There were a number of unusual findings, including the high rate of joint manifestations (29%) and the severe course of some hematologic and myocardial manifestations. These results raise the question of whether the HPV B19 may be involved in the genesis of chronic juvenile arthritis.


[Vaccination against measles at 6 months of age]. Measles immunization with the Edmonston Zagreb stain was carried out in 71 six-month-old infants. Proportions of subjects with immunity were 91% among the 47 subjects retested before one year of age and 100% among the 28 subjects retested between two and three years of age. These results support the WHO recommendation that measles immunization should be given at the age of six months. The concerns expressed by some about possible adverse effects of early measles immunization (decreased immune defenses) are discussed, as well as the transfer of maternal antibodies and persistence of these antibodies in the child. The obstacles to such studies in developing countries, including the need for repeated phlebotomies with centrifugation of specimens and freezing of sera, could be circumvented by the use of filter paper dried blood spot samples which seem to provide reliable results although with values somewhat lower than those found in frozen sera.


Suppression of murine retroviral disease by 2',3'-didehydro-2',3'-dideoxythymidine (D4T). The thymidine analog, 2',3'-didehydro-2',3'-dideoxythymidine (D4T), and 3'-azido-3'-deoxythymidine (AZT) were evaluated for activity against Friend virus complex (FV) in Mus dunni cells using a focal immunoenzyme assay. The 50% effective doses were, respectively, 1.2 and 0.1 microM for the two compounds; the 50% cytotoxic doses using trypan blue dye exclusion were 25.4 and > 100 microM. Four FV inhibition experiments with D4T were run in F1 hybrid mice containing the Rfv-3r/s genotype. This mouse strain allows the study of treatment effects on development of specific neutralizing antibodies and on splenomegaly, splenic and plasma virus titers, and splenic viral RNA. In the first experiment, D4T was given by oral gavage (p.o.) three times daily (t.i.d.) for 14 days beginning 4 h post-virus inoculation. All dosages used (187.5, 375, 750 mg/kg/day) significantly inhibited all viral parameters. Other experiments used D4T p.o. twice daily, with dosages of 46.9, 93.8, 187.5 and 375 mg/kg/day or four times daily with a dose of 375 mg/kg/day. No significant disease inhibition was seen using the twice daily treatment schedule, but efficacy was apparent using the four times daily treatment. The final experiment repeated the initial study, extending the t.i.d. treatments to 25 days and using dosages of 46.9, 93.8, 187.5 and 375 mg/kg/day. All but the lowest dose reduced each virus parameter. None of the D4T treatment regimens caused death in toxicity controls, although moderate host weight loss or less weight gain was seen, and variable hematocrit decreases occurred, particularly in mice receiving the highest drug dosage. Inhibition of natural killer (NK) cell activity also was seen in these same animals, but in infected mice, FV-induced decrease in NK cell activity was prevented by D4T treatment. Virus-specific neutralizing antibodies developed in all infected, treated animals. These data indicate D4T has potential as a possible candidate for anti-human immunodeficiency virus evaluations in the clinic.


Monitoring of ganciclovir sensitivity of multiple human cytomegalovirus strains coinfecting blood of an AIDS patient by an immediate-early antigen plaque assay. A plaque-reduction assay for chemosensitivity testing of human cytomegalovirus (HCMV) strains was developed based on early detection of viral plaques 96 h p.i. by a monoclonal antibody to the major immediate-early protein p72. Sequential HCMV isolates from an AIDS patient undergoing multiple courses of ganciclovir treatment during an 18-month follow-up were tested by the new assay, showing emergence of a ganciclovir-resistant strain. However, cloning of viral isolates and Southern blot hybridization analysis showed the simultaneous presence of three different HCMV strains in blood. Of these, the resistant strain was likely to be selected during prolonged maintenance antiviral treatment, emerging during full drug regimen, while the two sensitive strains reappeared in association with the resistant one following drug discontinuation. This finding was demonstrated by high levels of ID90 and ID99 in sequential mixed viral populations. The new plaque assay leads to reduction in time needed for chemosensitivity testing and permits rapid tracing of drug-resistant strains in a mixed viral population.


Protective effect of morphine on ethanol-induced gastric lesions in rats: are ATP-dependent potassium channels involved? Morphine has a significant protective effect on ethanol-induced gastric lesions. This effect is antagonized by naloxone, suggesting the involvement of opioid receptors. The ATP-dependent potassium channel blockers glibenclamide and phentolamine have different effects on this action of morphine. While glibenclamide potentiates the gastroprotective effect of morphine, phentolamine antagonizes it. However, both prazosin and yohimbine do not affect the gastroprotective action of morphine, suggesting that the influence of phentolamine is not mediated by alpha-adrenoceptors. As phentolamine also prevented the gastroprotective effect of the ATP-dependent K+ channel opener diazoxide, our results suggest that ATP-dependent K+ channels may be involved in the gastro-protective action of morphine.


Evidence for copper and 3,4,6-trihydroxyphenylalanine quinone cofactors in an amine oxidase from the gram-negative bacterium Escherichia coli K-12. The cofactors present in a amine oxidase induced in Escherichia coli K-12 by growth on 2-phenylethylamine have been studied by spectroscopic methods. E.s.r. spectroscopy establishes the presence of cupric copper while resonance Raman spectroscopy on the phenylhydrazine derivative of the enzyme provides strong evidence for the oxidized form of 3,4,6-trihydroxyphenylalanine (TOPA) quinone. The amine oxidase should accordingly be classified as EC 1.4.3.6. This is the first report of such an amine oxidase in a Gram-negative bacterium.


Inhibition of myocardial Na(+)-K(+)-ATPase activity by bretylium: role of potassium. The effects of bretylium on the Mg(2+)-dependent ATP-hydrolytic action of myocardial Na(+)-K(+)-ATPase (EC 3.6.1.3) were studied in guinea-pig heart preparations in media containing various K+ concentrations. Under "standard" conditions (5 mM K+), bretylium inhibited the Na(+)-K(+)-ATPase activity in a concentration-dependent fashion in the range of 0.001-80 mM, with an IC20 value of 0.19 +/- 0.05 mM and an IC50 value of 1.38 +/- 0.11 mM. Reducing the K+ concentration from 5 to 2.5 mM enhanced the inhibitory action, shifting the effective (5-95% inhibition) concentration range to 0.0003-9.6 mM, with IC20 and IC50 values of 0.036 +/- 0.004 mM and 0.92 +/- 0.30 mM, respectively. On the other hand, increasing the K+ concentration to 10 mM shifted the range to 10-90 mM. The corresponding IC20 value was 0.48 +/- 0.02 mM and the IC50 was 2.24 +/- 0.36 mM. The results show that K+ plays an important role in the inhibition of myocardial Na(+)-K(+)-ATPase activity by bretylium. This is probably pertinent to the mode by which the drug may interfere with the electrogenic Na+/K+ pump activity of the enzyme, and, consequently, cause or aggravate cardiac arrhythmias.


Free radical scavenger mechanisms in experimentally induced ischemia in the rabbit heart and protective effect of verapamil. The protective effect of verapamil on the free radical generation in the ischemic myocardium of rabbit has been studied. A significant decrease of the lactate dehydrogenase activity in the ischemic zone was observed compared to the nonischemic control myocardial tissue. The level of malondialdehyde was found to be elevated in the ischemic zone and in other parts of the myocardium. However, there was no alteration in glutathione content in both zones. In addition, an increase in the activity of myeloperoxidase was observed in the ischemic part of the myocardium. At lower doses (30 micrograms/kg), verapamil protected the animals from ischemic changes but did not do so at higher doses (100 micrograms/kg). These results suggest that, in the rabbit, the free radical scavenging mechanism of the heart is not adversely affected during ischemia.


Voltage dependence of force- and slow inward current restitution in ventricular muscle. This study was aimed to assess the relationship among the voltage-dependent processes underlying the excitation-contraction coupling, viz. force restitution (FR), transmembrane Ca fluxes and Ca release. The experiments (n = 22) were performed on voltage-clamped dog trabeculae in which force and slow inward current were measured. Standard steady-state was achieved by clamp driving at 0.5 Hz, 300 ms, 70 mV depolarizing pulses from holding = resting potential at 30 degrees C. Voltage and duration of single pulses and intervals in between were varied according to five protocols. The voltage dependence of Ca release was tested by varying single pulses at equal steady-state, i.e., at equal Ca availability. Contractions could be elicited in absence of ICa (20-30 mV step) and in the presence of disproportionately small ICa (above 80 mV). The voltage dependence of Ca availability for the release was tested by constant test pulses following either a variable conditioning clamp pulse or a period of rest at a variable voltage. After a low voltage pulse and, hence, depressed or absent ICa, the test contraction is diminished in presence of normal or even augmented Isi at any test interval (i.e., FR is depressed). Diminished Ca influx thus reduces the Ca availability of the subsequent beat. During prolonged depolarization (by 60 mV and more) a tonic response appears, but a phasic response cannot be elicited (FR is inhibited). Upon subsequent repolarization FR starts from zero and is significantly enhanced. It is concluded that, during depolarization, Ca release channels are in an open state, thus allowing free recirculation of Ca, but no build-up of a sufficient Ca gradient at the release site.


Increases in endothelial cyclic AMP levels amplify agonist-induced formation of endothelium-derived relaxing factor (EDRF). The interaction between intracellular cyclic AMP and agonist-induced endothelium-derived relaxing factor (EDRF) (NO) formation was investigated in pig aortic endothelial cells. Three potent stimulators of adenylate cyclase, namely forskolin, adenosine and isoprenaline, amplified bradykinin- and ATP-induced biosynthesis and release of EDRF. None of the substances by itself affected basal EDRF formation. The effects of forskolin, adenosine and isoprenaline corresponded to an enhanced agonist-induced rise in intracellular free Ca2+ concentration ([Ca2+]i), were mimicked by the membrane-permeable cyclic AMP analogue dibutyryl cyclic AMP and were antagonized by the protein kinase inhibitor N-[2-(methylamino)ethyl]-5-isoquinolinesulphonamide dihydrochloride (H-8). Our data suggest that cyclic AMP-dependent phosphorylation modulates Ca(2+)-signalling and thus the function of endothelial cells. This mechanism may be of particular physiological importance, since it allows a joint regulation of endothelial functions by tissues factors such as bradykinin, which directly affects [Ca2+]i and agonists which affect intracellular cyclic AMP levels.


Sustained activation of the mitogen-activated protein (MAP) kinase cascade may be required for differentiation of PC12 cells. Comparison of the effects of nerve growth factor and epidermal growth factor. Stimulation of PC12 cells with nerve growth factor (NGF) increased mitogen-activated protein kinase kinase (MAPKK) activity > 20-fold after 5 min to a level that was largely sustained for at least 90 min. MAPKK activity was stimulated to a similar level by epidermal growth factor (EGF), but peaked at 2 min, declining thereafter and returning to basal levels after 60-90 min. Activation of MAPKK by either growth factor occurred prior to the activation of MAP kinase, consistent with MAPKK being the physiological activator of MAP kinase. The results demonstrate that the transient activation of MAPKK by EGF and its sustained activation by NGF underlies the transient and sustained activation of MAP kinase induced by EGF and NGF respectively. NGF or EGF induced the same two forms of MAPKK that were resolved on a Mono Q column. The Peak-1 MAPKK was activated initially and partially converted into the more acidic peak-2 MAPKK after prolonged growth-factor stimulation. The Peak-2 MAPKK was 20-fold more sensitive to inactivation by the catalytic subunit of protein phosphatase 2A. Stimulation with NGF caused a striking translocation of MAP kinase from the cytosol to the nucleus after 30 min, but not nuclear translocation of MAP kinase occurred after stimulation with EGF. The results suggest that sustained activation of the MAP kinase cascade may be required for MAP kinase to enter the nucleus, where it may initiate the gene transcription events required for neuronal differentiation of PC12 cells.


Oscillations of cytosolic free calcium concentration in the presence of intracellular antibodies to phosphatidylinositol 4,5-bisphosphate in voltage-clamped guinea-pig hepatocytes. In liver cells, the stimulation of alpha 1-adrenoceptors by noradrenaline induces the production of Ins(1,4,5)P3 through the degradation of membrane polyphosphoinositides [PtdIns(4,5)P2]. InsP3 evokes in turn the release of Ca2+ from internal stores. Our results show that the internal perfusion of single guinea-pig hepatocytes with monoclonal anti-PtdInsP2 antibody blocks the rise in cytosolic free Ca2+ concn. ([Ca2+]i) evoked by noradrenaline, an InsP3-dependent agonist, but not by the monohydroxylated bile acid taurolithocholate 3-sulphate, which is known to permeabilize the endoplasmic reticulum. In these conditions, the bile acid elicited either fast or slow fluctuations of [Ca2+]i independently of any InsP3 production. The responses to the bile acid were also observed in the absence of external Ca2+. The presence of intracellular anti-PtdInsP2 antibody does not affect the response to a photolytic release of InsP3 (1.5 microM final concn.) from a caged precursor.


Expression and characterization of the p85 subunit of the phosphatidylinositol 3-kinase complex and a related p85 beta protein by using the baculovirus expression system. PtdIns 3-kinase associates with certain activated protein-tyrosine kinase receptors and with the pp60c-src/polyoma middle-T complex, suggesting that the enzyme is involved in growth regulation. The purified PtdIns 3-kinase appears to have two subunits, of 85 kDa and 110 kDa. Structural analysis at protein and cDNA levels revealed two forms of the 85 kDa subunit, one which associates with PtdIns 3-kinase activity termed p85 alpha, and a protein of unknown function, p85 beta. Both 85 kDa proteins contain src-homology regions 2 and 3 (SH2 and SH3), but lack enzymic activity, suggesting that they may be regulatory subunits of PtdIns 3-kinase. To probe their structure and function further, p85 alpha and p85 beta have been expressed and purified in large amounts from insect cells by using baculovirus vectors. Specific antisera detect p85 alpha, but not p85 beta, associated with PtdIns 3-kinase activity in various cell types. Co-expression studies in insect cells have shown that p85 alpha and p85 beta are substrates for the protein-tyrosine kinases of epidermal growth factor, colony-stimulating factor 1 and c-erbB2 receptors and the src family kinase p59c-fyn. Both p85 alpha and p85 beta form tight complexes with these protein-tyrosine kinases as measured by immunoprecipitation and kinase assays in vitro. The specificity of binding of free p85 is less restricted than that of p85 in the active PtdIns 3-kinase complex with the 110 kDa protein. The relevance of these results to growth-factor-induced PtdIns 3-kinase activation is discussed.


Attenuation of the systemic and coronary hemodynamic effects of cocaine in conscious dogs: propranolol versus labetalol. The interaction of cocaine with myocardial and vascular adrenoceptors is incompletely understood. The systemic and coronary hemodynamic effects of intravenous cocaine (1.5 mg/kg) were examined in dogs with and without pretreatment with propranolol (2 mg/kg i.v.) or labetalol (5 mg/kg i.v.) on different days. A total of 24 experiments was completed (three sets of experiments) using eight dogs chronically instrumented for measurement of aortic and left-ventricular pressure, left-ventricular dP/dt, subendocardial segment length, coronary blood flow, and cardiac output. Myocardial oxygen consumption was estimated from the pressure work index (PWI). Cocaine significantly (p < 0.05) increased heart rate (+51 +/- 17 bpm), mean arterial pressure (+72 +/- 10 mm Hg), left-ventricular systolic and end-diastolic pressures (+56 +/- 9 and +14 +/- 6 mm Hg, respectively), coronary blood flow (+32 +/- 10 ml/min) and the PWI (+10.0 +/- 2.3 ml O2/min/100 g). Significant reductions in stroke volume (-9 +/- 5 ml) and percent segment shortening (-7.1 +/- 1.7) were observed. These changes returned to control after 30 min. After pretreatment with propranolol, the cocaine-mediated increases in mean arterial pressure, left-ventricular systolic pressure, rate-pressure product, and the pressure work index (4.4 +/- 0.7 ml O2/min/100 g) were significantly (p < 0.05) less than those observed with cocaine alone. Cocaine also reduced contractility [dP/dt50 (-341 +/- 80 mm Hg/s)] and increased systemic vascular resistance (+2703 +/- 339 dyn.s.cm-5) in the presence of propranolol. Labetalol abolished the cocaine-mediated increases in heart rate and coronary blood flow and significantly attenuated the increases in mean arterial pressure, left-ventricular systolic pressure, cardiac output, rate-pressure product, and calculated myocardial oxygen consumption when compared to results obtained with cocaine alone. The results demonstrate that a portion of the basic dynamic effects of cocaine is mediated by stimulation of alpha and beta adrenoceptors. Combined alpha and beta adrenergic blockade reduces the hemodynamic effects of cocaine more than beta blockade alone. During antagonism of the sympathomimetic response of cocaine, direct negative inotropic actions of this drug are unmasked.


Role of glucose 6-phosphate in the translocation of glycogen synthase in rat hepatocytes. Incubation of rat hepatocytes with glucose induces the translocation of glycogen synthase from soluble fractions to fractions which sediment at 10,000 g. Incubation of the cells with fructose, galactose, 2-deoxyglucose or 5-thioglucose, which activate glycogen synthase, also resulted in the translocation of the enzyme, whereas 3-O-methylglucose, 6-deoxyglucose and 1,5-anhydroglucitol, which do not cause the activation of the enzyme, were ineffective. Adenosine and carbonyl cyanide m-chlorophenylhydrazone, although activating glycogen synthase, did not induce its translocation. Mannoheptulose, which inhibits glucose phosphorylation, impaired the translocation of glycogen synthase induced by glucose. Furthermore, the extent of the translocation of the enzyme triggered by glucose and other sugars showed a high positive correlation with the intracellular concentration of glucose 6-phosphate. Microcystin, which blocks the activation of glycogen synthase by glucose, but not the accumulation of glucose 6-phosphate, did not affect the translocation of the enzyme. These results indicate that glucose 6-phosphate plays a role in the translocation of glycogen synthase in rat hepatocytes.


Domains of the catalytically self-sufficient cytochrome P-450 BM-3. Genetic construction, overexpression, purification and spectroscopic characterization. 1. The gene CYP102 encoding cytochrome P-450 BM-3 and subgenes encoding the cytochrome P-450 and cytochrome P-450 reductase domains have been cloned in Escherichia coli. 2. The protein products of these genes have been overexpressed and purified to homogeneity. 3. The cytochrome P-450 domain is purified in the ferric low-spin state, but is readily converted into the high-spin state by addition of the substrate palmitate (Ks = 1 microM). The cytochrome P-450 reductase domain readily reduces cytochrome c. Mixing the two domains reconstitutes only about one-thousandth of the fatty acid hydroxylase activity associated with the intact cytochrome P-450 BM-3. 4. The X-band e.p.r. spectra of both the cytochrome P-450 domain and intact cytochrome P-450 BM-3 give g-values indicating low-spin ferric haem. The spectra are virtually identical with those of the equivalent form of cytochrome P-450 cam indicating that the haem ligation in cytochrome P-450 BM-3 is identical with that of cytochrome P-450 cam. 5. Resonance Raman spectra of the substrate-free and substrate-bound forms of the cytochrome P-450 domain are given. Spectral differences in comparison with cytochrome P-450 cam may reflect subtle electronic differences between the respective haem environments.


Expression of a cardiac Ca(2+)-release channel isoform in mammalian brain. Mammalian brain possesses ryanodine-sensitive Ca2+ channels, which in muscle cells mediate rapid Ca2+ release from intracellular stores during excitation-contraction coupling. Analysis of bovine brain ryanodine receptor (RyR) channels suggests specific expression of the cardiac-muscle RyR isoform in mammalian brain. Localization using cardiac-muscle RyR-specific antibodies and antisense RNA revealed that brain RyRs were present in dendrites, cell bodies and terminals of rat forebrain, and highly enriched in the hippocampus. Activity of skeletal-muscle RyR channels is coupled to sarcolemmal voltage sensors, in contrast with cardiac-muscle RyR channels, which are known to be Ca(2+)-induced Ca(2+)-release channels. Thus Ca(2+)-induced Ca2+ release from intracellular stores mediated by brain RyR channels may be a major Ca(2+)-signalling pathway in specific regions of mammalian brain, and hence may play a fundamental role in neuronal Ca2+ homoeostasis.


Characterization of noradrenaline-stimulated cyclic GMP formation in brain astrocytes in culture. Cyclic GMP accumulation induced by noradrenaline in astrocyte-enriched primary cultures from rat cerebrum involves synthesis of NO, as evidenced by the competitive inhibition exerted by the NO synthase inhibitor NG-monomethyl-L-arginine (IC50 = 3 microM). Furthermore, the noradrenaline effect was potently inhibited by haemoglobin (IC50 = 25 nM) and potentiated by superoxide dismutase, indicating that NO synthesis and cyclic GMP formation may occur in different subsets of astrocytes. Investigation of the receptors implicated by using selective adrenoceptor agonists and antagonists indicates that about 75% of the NO-dependent noradrenaline response is mediated by alpha 1-adrenoceptors and the rest by beta-adrenoceptors, with no evidence for potentiating effects between the two receptor types. This noradrenaline effect appears to require Ca2+ entry, since it is strongly dependent on extracellular Ca2+ but is not affected by conditions that will abolish intracellular Ca2+ mobilization (incubation with neomycin or pretreatment with carbachol). Inhibition by pretreatment with pertussis toxin is in agreement with involvement of the alpha 1A-adrenoceptor subtype in this Ca(2+)-dependent effect. However, implication of an unknown alpha 1-adrenoceptor subtype cannot be disregarded, because a similar inhibition is exerted by the presumably selective alpha 1B- and alpha 1C-adrenoceptor blocking agent chloroethylclonidine. Treatment of the cultures with the protein kinase C activator phorbol 12-myristate 13-acetate inhibits to a great extent the noradrenaline-induced cyclic GMP formation.


Cyclic AMP impairs the rapid effect of insulin to enhance cell-surface insulin-binding capacity in rat adipocytes. The aim of this study was to characterize further the interaction between cyclic AMP (cAMP) and insulin binding and action. Rat adipocytes were preincubated at 37 degrees C for 20 min, and after energy depletion with KCN, cell-surface 125I-insulin binding was measured. As recently reported [Eriksson, Lönnroth & Smith (1992) Diabetes 41, 707-714], preincubation with insulin rapidly increased the number of cell-surface insulin binding sites up to approximately 5-fold through recruitment within the plasma membrane. This was completely abolished by the presence of 4 mM-N6-monobutyryl cAMP (a non-hydrolysable cAMP analogue) or 1 microM-isoprenaline, without any apparent change in receptor internalization. Insulin-stimulated receptor tyrosine kinase activity was attenuated by the cAMP analogue only if the exposure of the adipocytes was prolonged to 60 min. The cellular sensitivity to insulin, assessed as 3-O-methylglucose uptake, was markedly decreased by the cAMP analogue, and this could be attributed to the impaired cell-surface binding. However, evidence for post-receptor interactions between cAMP and insulin was also found: an impairment of maximal insulin-stimulated 3-O-methylglucose transport and a delay in the rate of activation of the glucose transport system by insulin. In conclusion, these data demonstrate that beta-adrenergic stimulation and elevated cAMP levels markedly impair the ability of insulin to enhance cell-surface insulin-binding capacity. This novel interaction may be an important mechanism for the cellular insensitivity to insulin produced by cAMP.


Purification and characterization of phosphatidylinositol 4-phosphate 5-kinases. We detail the purification and characterization of three distinct isoforms of PtdIns4P 5-kinase present in bovine brain. One of these, PtdIns4P 5-kinase C, was purified to apparent homogeneity, and SDS/PAGE analysis demonstrated a single polypeptide and molecular mass 53 KDa. These three isoforms were shown to differ in their kinetic properties, and immunological characterization with an antibody raised to PtdIns4P 5-kinase C demonstrated that this isoform was unrelated to the other two. Furthermore, PtdIns4P 5-kinase C was shown to be the bovine brain homologue of the Type II PtdIns4P 5-kinase previously purified from human erythrocytes [Bazenet, Ruano, Brockman & Anderson (1990) J. Biol. Chem. 265, 18012-18022].


Spectroscopic studies on an oxygen-binding haemoglobin-like flavohaemoprotein from Escherichia coli. The Escherichia coli haemoglobin-like flavohaemoprotein (Hmp) has been purified to near homogeneity using two chromatographic steps. The prosthetic groups are identified as FAD and protohaem IX. SDS/PAGE has indicated a molecular mass of 44 kDa for the monomeric protein consistent with the amino-acid sequence deduced from the hmp+ gene. The protein, as isolated, is in the Fe(III) state, exhibiting absorbance maxima at 403.5, 540 (shoulder) and 627 nm. The ferrous and carbonmonoxyferrous states resemble those of haemoglobin, showing maxima at 431.5 and 558 nm, and 421, 542 and 566 nm respectively. Upon aerobic addition of NAD(P)H, the ferric state is reduced to the oxygenated Fe(II) state, characterized by maxima at 413, 544 and 580 nm. This oxy form is not stable and slowly decays to the ferric state. Addition of dithionite and nitrite to the ferric protein results in the formation of a nitrosyl complex, whose e.p.r. characteristics indicate that the b-type haem is attached to the protein through a nitrogenous ligand, probably originating from a histidine residue.


Epidemiology of nasopharyngeal and salivary gland carcinoma in Greenland. From 1950 to 1989 one hundred and forty-four cases of either undifferentiated nasopharyngeal carcinoma (NPC) or salivary gland carcinoma (SGC) were diagnosed in Greenlanders, all born in Greenland. The Greenland SGC is an anaplastic carcinoma with histopathology and electronmicroscopic cytopathological alterations as found in undifferentiated NPC. Both NPC and SGC from Greenland and Alaska are associated with Epstein-Barr virus infection. The incidence rate of NPC based on newly diagnosed cases during the last 15 years is 12.7 for men and 9.2 for women. The same figures for anaplastic SGC are 3.4 and 3.1. These are among the highest incidence rates of Epstein-Barr virus associated carcinomas on record. From 1950 to 1989 there has been an increase in the rate of NPC. From the cumulated rate, it can be predicted that the number of cases will continue to increase during the years to come. During the ten year period 1980 to 1989 patients were questioned about their childhood life style and the family history was taken. The Inuit lifestyle is quite different from that of Europeans and Chinese, but in common with Chinese from Guangzhou (formerly Canton) Greenlanders have a high consumption of fish, fresh as well as dried. Familial clustering has been rarely reported, but in the present investigation 27% of the patients diagnosed between 1980 and 1990 had a positive familial history with one or more confirmed cases among first degree relatives.(ABSTRACT TRUNCATED AT 250 WORDS)


Do we know the site of action of cyclosporin? The site and mode of action of cyclosporin A (CsA) have been subjects of study ever since CsA was discovered and demonstrated to be a selective suppressor of allograft rejection. In this article, Bernard Erlanger traces progress to date and presents evidence that the site of action is not cytoplasmic cyclophilin but a lymphocyte cell-surface receptor that might be related in structure to cyclophilin.


Effect of prenatal exposure to tianeptine on different neurotransmitter receptors and 5-HT-stimulated inositol phosphate formation in rat brain. Tianeptine, an antidepressant drug enhancing 5-HT uptake, was given to pregnant rats in the last 15 days of gestation and different neurotransmitter receptors as well as 5-HT2 receptor-linked inositol phosphate formation were measured in the brains of the offspring. Prenatal exposure to tianeptine significantly decreased the density of 3H-imipramine binding sites in the cerebral cortex of the pups without affecting beta-adrenoceptors, serotonin 5-HT2 and 5-HT1B receptors or inositol phosphate formation after a 5-HT challenge. Striatal dopamine D2 receptors labelled with 3H-spiroperidol were not changed but an apparent increase in the affinity of dopamine was noticed in the pups prenatally exposed to the drug. The results show that the neurochemical profile of tianeptine markedly differs from that of most antidepressants.


Binding of botulinum neurotoxin to pure cholinergic nerve terminals isolated from the electric organ of Torpedo. Torpedo electric organ has been used to study the binding of botulinum neurotoxin type A to pure cholinergic synaptosomes and presynaptic plasma membrane. 125I-labeled botulinum neurotoxin type A exhibits specific binding to cholinergic fractions. Two binding sites have been determined according to data analysis: a high affinity binding site (synaptosomes: Kd = 0.11 +/- 0.03 nM, Bmax = 50 +/- 10 fmol.mg prot-1; presynaptic plasma membrane: Kd = 0.2 +/- 0.05 nM, Bmax = 150 +/- 15 fmol.mg prot-1) and a low affinity binding site (synaptosomes: Kd approximately 26 nM, Bmax approximately 7.5 pmol.mg prot-1; presynaptic plasma membrane: Kd approximately 30 nM, Bmax approximately 52 pmol.mg prot-1). The binding of 125I-botulinum neurotoxin type A is decreased by previous treatment of synaptosomes by neuraminidase and trypsin, and by a preincubation with bovine brain gangliosides or antiserum raised against Torpedo presynaptic plasma membrane. When presynaptic plasma membranes are blotted to nitrocellulose sheet, either 125I-botulinum neurotoxin or botulinum toxin-gold complexes bind to a M(r) approximately 140,000 protein. Botulinum toxin-gold complexes have also been used to study the toxin internalization process into Torpedo synaptosomes. The images fit the three step sequence model in the pathway of botulinum neurotoxin poisoning.


Direct measurement of quantal changes underlying long-term potentiation in CA1 hippocampus. The modification responsible for the long-term synaptic potentiation (LTP) that follows a brief conditioning period is not known. To elucidate this change, we have resolved quantal levels of transmission before and after induction of LTP. We find an increase both in the number of quanta released and in quantal amplitude, consistent with combined pre- and postsynaptic modifications. On average, about 60% of LTP can be accounted for by presynaptic enhancement. The increase in either quantal amplitude or quantal content varies significantly among different experiments, but is inversely correlated with its initial value. These results may help to reconcile the different views concerning the site of LTP expression.


Biochemical properties and subcellular distribution of an N-type calcium channel alpha 1 subunit. A site-directed anti-peptide antibody, CNB-1, that recognizes the alpha 1 subunit of rat brain class B calcium channels (rbB) immunoprecipitated 43% of the N-type calcium channels labeled by [125I]omega-conotoxin. CNB-1 recognized proteins of 240 and 210 kd, suggesting the presence of two size forms of this alpha 1 subunit. Calcium channels recognized by CNB-1 were localized predominantly in dendrites; both dendritic shafts and punctate synaptic structures upon the dendrites were labeled. The large terminals of the mossy fibers of the dentate gyrus granule neurons were heavily labeled, suggesting that the punctate labeling pattern represents calcium channels in nerve terminals. The pattern of immunostaining was cell specific. The cell bodies of some pyramidal cells in layers II, III, and V of the dorsal cortex, Purkinje cells, and scattered cell bodies elsewhere in the brain were also labeled at a low level. The results define complementary distributions of N- and L-type calcium channels in dendrites, nerve terminals, and cell bodies of most central neurons and support distinct functional roles in calcium-dependent electrical activity, intracellular calcium regulation, and neurotransmitter release for these two channel types.


Two types of ryanodine receptors in mouse brain: skeletal muscle type exclusively in Purkinje cells and cardiac muscle type in various neurons. Two types of ryanodine receptors, channels for Ca2+ release from intracellular stores, are known. We detected the skeletal muscle type only in cerebellum by immunoblot analysis of microsomes and partially purified proteins. The cardiac muscle type was found in all parts of the mouse brain. Immunohistochemical study showed that the cardiac muscle type was localized mainly at the somata of most neurons. Analysis of mutant cerebella suggested that the skeletal muscle type was present exclusively in Purkinje cells. These results suggest that Ca(2+)-induced Ca2+ release, probably mediated by the cardiac muscle receptor, functions generally in various neurons, whereas depolarization-induced Ca2+ release, probably mediated by the skeletal muscle receptor, functions specifically in Purkinje cells.