Molecular basis of discrepancies in neurotoxic properties among 1-methyl-4-aryl-1,2,3,6-tetrahydropyridines. The relationship between structural specificity of the main stages of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) action and the display of parkinsonogenic properties among homologous structures in a number of 4-tolyl derivatives of MPTP has been studied. All the compounds are better substrates for monoamine oxidase (MAO) than MPTP. MAO is inactivated during the reaction according to a mechanism of irreversible inhibition by 2,3-dihydropyridinium metabolite. All the tolyl derivatives are stronger inhibitors of MAO than 1-methyl-2,3-dihydropyridinium (MPDP). A significant contribution of enzyme inhibition to the catalytic conversion of the substrate leads to the fact that substrates having equal (para isomer) or even higher (meta isomer) values of catalytic parameters are oxidized by MAO to a lesser extent than MPTP. It has been found that all 4-arylpyridiniums (final products of MATP bioconversion) competitively and reversibly inhibit [14C]dopamine (DA) uptake in mouse brain synaptosomes. Affinity toward DA transporter characterized by KI (microM) is 0.37 +/- 0.04, 0.7 +/- 0.1, 2.0 +/- 0.15, 2.0 +/- 0.35 for MPP, and its o-, m-, and p-tolyl derivatives, respectively. Joint calculation of specificity factors for the processes discussed define the following rank order for the bio-delivery of MATP's metabolic produces into DA nerve terminals: o-tolyl > MPTP >> m-tolyl > p-tolyl. The regularity revealed is in good agreement with the observed relative potency of these compounds to cause dopaminergic neurodegeneration.


Somatostatin concentrations in cerebrospinal fluid and brain tissue of patients with refractory epilepsy. The somatostatin concentrations of cerebrospinal fluid (CSF) and brain tissue in 16 refractory epileptic patients were measured simultaneously by a radioimmunoassay (RIA) method. An increased level of somatostatin was found in the epileptic foci of cerebral cortex, determined by the cortical EEG. There were significant differences among the epileptic foci (75.58 +/- 6.58 pg/mg wet wt, +/- SEM), nonfocal tissues (37.04 +/- 6.55 pg/mg), and normal tissues of control patients (47.69 +/- 10.12 pg/mg), p < 0.001 and p < 0.05, respectively. The somatostatin concentrations of CSF in 11 epileptic patients were determined before (257.78 +/- 19.11 pg/mL) and after (178.36 +/- 8.78 pg/mL) the removal of epileptic focal area, and a dramatic decrease of the CSF somatostatin concentration after operation was detected (p < 0.01). We also found that the somatostatin level of cerebral scar induced by head injury in cases of posttraumatic epilepsy was highest (106.39 +/- 12.41 pg/mg). The results suggested that the surgical removal of the epileptic focal area in refractory epileptic patients may reduce the increased central somatostatin level, which could play an important part in the pathophysiological process of refractory epilepsy.


PASSHIV-1 treatment of patients with HIV-1 infection. A preliminary report of a phase I trial of hyperimmune porcine immunoglobulin to HIV-1. To study the safety of intravenously administered porcine-derived hyperimmune immunoglobulin to HIV-1, PASSHIV-1, in humans. Fourteen HIV-1-infected individuals were treated for 5-7 days with intravenous infusions of highly purified PASSHIV-1 (> 95% pure). Two of the 14 patients were retreated 3 months later with PASSHIV-1 for an additional 5 days to evaluate side-effects from retreatment with porcine immunoglobulins. Ten of the patients had no side-effects from PASSHIV-1 therapy. Three patients experienced transient urticarial eruptions, which responded to antihistamine administration and did not require discontinuation of therapy. One patient, who received concomitant administration of human gammaglobulin, experienced serum sickness (type 3 hypersensitivity reaction). All patients demonstrated a significant improvement in fatigue (100% response), weight (all those with previous weight loss gained weight), fever (100% response), polyneuropathy (100% response), bronchitis (100% response), candidiasis (100% response), diarrhea (100% response), and dermatitis (100% response). One out of the five patients with Kaposi's sarcoma demonstrated > 50% improvement. Mean CD4+ cell counts in the group rose from 143 +/- 263 to 234 +/- 323 x 10(6)/l 4-6 months following completion of therapy (P = 0.013, paired Student's t-test); CD4+ counts rose > twofold in six individuals. p24 antigen, present in four patients, was negative following therapy in all patients. Other laboratory parameters that responded to therapy included: platelet counts (71% response), leukopenia (57% response), elevated lactic dehydrogenase (100% response), and elevated alkaline phosphatase (100% response). PASSHIV-1 was well tolerated by HIV-1-infected individuals. This therapy appears to be efficacious in ameliorating some of the clinical aspects and symptoms of HIV-1 infection.


Salmonella, Campylobacter and Shigella in HIV-seropositive patients. To study the incidence, clinical features, treatment and outcome of patients with Salmonella, Shigella or Campylobacter infection. Retrospective analysis. Two dedicated HIV units within a London teaching hospital. All patients with Salmonella, Shigella or Campylobacter infection were reviewed retrospectively by correlating the records of the gastrointestinal and microbiology departments with the computerized records of all HIV-positive patients attending the two clinics. Between July 1985 and June 1991, 56 episodes of Salmonella, 37 of Campylobacter and eight of Shigella infection were documented in HIV-seropositive patients. Shigella was most likely to occur early in HIV disease, whilst patients with Campylobacter or Salmonella were more likely to have had a previous AIDS diagnosis. Septicaemica was most common in patients with Salmonella and was especially likely to occur in individuals with an AIDS diagnosis. Relapse of infection was common in patients with Salmonella, especially in those with low CD4 lymphocyte counts, those with an initial septicaemic illness and those not treated with ciprofloxacin. Patients with Salmonella who have low CD4 lymphocytes counts and/or a septicaemic illness should be considered for life-long secondary prophylaxis with ciprofloxacin because of the high rate of relapse observed. Administration of zidovudine or cotrimoxazole as prophylaxis against Pneumocystis carinii pneumonia may prevent the development of salmonellosis: significantly fewer patients with this infection were taking these drugs than patients with Campylobacter.


Visceral leishmaniasis in HIV-1-infected individuals: a common opportunistic infection in Spain? To investigate the epidemiological, clinical and biological features of visceral leishmaniasis (VL) in patients with HIV-1 infection. Retrospective study. Three university hospitals in southern Spain. Forty-seven adult patients with VL and HIV-1 infection diagnosed between January 1986 and November 1991. Forty-five out of the 47 (96%) cases were diagnosed in the last 2 years. Fever (87%), hepatomegaly (74%), splenomegaly (72%) and pancytopenia (77%) were the most common presenting features. Most patients (79%) were strongly immunocompromised when VL was diagnosed, and were in stage IV of the Centers for Disease Control classification; 87% had a CD4 lymphocyte count < 200 x 10(6)/l. However, VL was the first severe infection diagnosed in 10 cases. Significant titres (> 1:40) of antileishmanial antibodies were detected by indirect immunofluorescence in five out of 16 (31%) cases only. Clinical response to the therapy was difficult to assess. Microbiological response was achieved in only 38% of the patients evaluated. Leishmaniasis is a relatively common infection in HIV-1-infected individuals in southern Spain. Its clinical picture is quite uniform and it can be the first opportunistic infection in individuals with HIV-1. In endemic areas, a high index of clinical suspicion should be maintained in order to avoid underdiagnosis of leishmaniasis.


Quantitative determination of zetidoline, a new antipsychotic agent, in human blood plasma and saliva using capillary gas chromatograph-mass spectrometry. A specific and sensitive assay is described. Zetidoline is extracted with ethyl ether from 1 ml of plasma or saliva added with the internal standard. The extract is carefully purified and injected into a gas chromatography-mass spectrometry system equipped with a crosslinked capillary column and operated in single ion monitoring mode by electron impact. Quantitative response is linear in the range 2-50 ng/ml. The detection limit is 1 ng/ml.


Fimbriae of Branhamella catarrhalis as possible mediators of adherence to pharyngeal epithelial cells. This study attempted to elucidate the role of fimbriae in the adherence of B. catarrhalis to human oropharyngeal epithelial cells. Antifimbrial immune serum was prepared by immunization of rabbit with whole fimbriated bacteria, and adsorption of the serum with a nonfimbriated B. catarrhalis strain. After pretreatment with the antifimbrial antiserum, the adherence of fimbriated B. catarrhalis to human epithelial cells was significantly decreased (p < 0.05). The adherence was also significantly (p < 0.001) decreased by trypsin treatment. Electron microscopy revealed destruction of fimbriae after trypsin treatment. These observations suggest that fimbriae are involved in the adherence of B. catarrhalis to epithelial cells.


CD4 lymphocyte decline and survival in human immunodeficiency virus infection. The Military Medical Consortium for Applied Retroviral Research. The loss of the CD4 lymphocyte is the central pathophysiologic event in the progression of human immunodeficiency virus (HIV) infection. This retrospective study, based on review of data from deceased HIV patients followed in a single HIV clinic, was conducted to determine if the rate of CD4 lymphocyte decline was predictive of survival. Forty of 172 patients met defined criteria for inclusion in this study. For each patient, CD4-cell counts showed approximate exponential decline over time. A Cox regression analysis was used to assess the association of CD4 cell decline (half-life), race, age, gender, initial CD4-cell count, and treatment (anti-Pneumocystis carinii pneumonia prophylaxis and/or zidovudine vs. no therapy) on total survival (from initial CD4 cell count) and on remaining survival time after reaching a CD4 cell count of 100 (estimated). For all patients, the rate of CD4 cell decline was predictive of total survival (p = .009) but not for survival after reaching a count of 100 (p = .6). For patients who had never received therapy (6 patients), however, the CD4 half-life remained associated with survival time from 100 CD4 cells (p < .05) as opposed to the treated patients. Therapy was the single variable most predictive of both survival endpoints, resulting in an increase in median total survival of 27.2 mo (p < .00001) and of 15.4 mo from a CD4 cell count of 100 (p < .00004). Nonwhites had a slight survival disadvantage compared to whites (p = .08 overall; p = .02 from CD4 cell count of 100).(ABSTRACT TRUNCATED AT 250 WORDS)


A preliminary, clinical pharmacological assessment of L-659,066, a novel alpha 2-adrenoceptor antagonist. 1. The alpha 2-adrenoceptor antagonist activity of L-659,066 has been investigated in studies of healthy normotensive males to whom doses of up to 8 mg were administered by short intravenous infusion. 2. L-659,066 had no effect on basal levels of glucose or insulin and no significant effect on the plasma glucose and plasma insulin time profiles following an intravenous glucose load. 3. There was a non-significant trend for plasma noradrenaline concentrations to be higher after L-659,066. 4. L-659,066 had no significant effects on mood changes or on physical symptom scores. 5. There were no significant effects on supine blood pressure but there were consistent increases in heart rate both supine (non-significant) and erect (P < 0.01). 6. Ex vivo platelet aggregation studies confirmed alpha 2-adrenoceptor antagonist activity with L-659,066 but with an approximately 9-fold lesser potency than yohimbine. 7. While L-659,066 has alpha 2-adrenoceptor antagonist activity these results suggest that it is unlikely to present a new therapeutic approach for improving insulin release.


Effect of 3 weeks treatment with yohimbine on salivary secretion in healthy volunteers and in depressed patients treated with tricyclic antidepressants. The effect of yohimbine treatment (4 mg three times daily) for 3 weeks on salivary secretion was investigated. In healthy volunteers, acute administration of yohimbine increased salivary volume within 1 h to a similar extent before and at the end of the treatment period. In depressed patients treated with tricyclic antidepressants (and exhibiting a reduced salivary flow), yohimbine also acutely increased salivary volume. In contrast, the alpha 2-adrenoceptor antagonist failed to modify resting values measured in the morning (i.e. 10 and 14 h after the last administration in healthy volunteers and depressed patients respectively). This result indicates that alpha 2-adrenoceptor antagonists may have a potential therapeutic use in the treatment of dry mouth caused by tricyclic antidepressant drugs.


Diagnosis of drug-induced psoriasis.

Diagnosis of drug-induced psoriasis. Certain drugs have been reported to precipitate or to exacerbate psoriasis. These cases occur mostly in patients with a history of psoriasis, although occasionally the new onset of psoriasis has followed treatment with certain drugs. The suspect drugs include lithium, beta adrenergic antagonists, antimalarials, and non-steroidal anti-inflammatory drugs (NSAID), in addition to various miscellaneous agents, including tetracycline. Evidence for these reports must be critically examined based on clinical and histological data, time course between drug intake and psoriasis exacerbation or resistance to psoriasis therapy, and response to drug rechallenge when available. The clinical context must be taken into consideration, including effects of concomitant antipsoriatic therapy, and the possible role of other triggering factors, such as infection. Controlled, prospective studies of the use of NSAID in patients with psoriasis may help to clarify their varied cutaneous effects. Further knowledge of the mechanisms involved in drug exacerbation of psoriasis may help to elucidate the etiopathogenesis of this chronic skin disorder.


Replacement of butter on bread by rapeseed oil and rapeseed oil-containing margarine: effects on plasma fatty acid composition and serum cholesterol. The effects of zero-erucic acid rapeseed oil and rapeseed oil-containing margarine on plasma fatty acid composition and serum cholesterol were studied in butter users (n 43). Compliance to the substitution was followed by fatty acid analysis of total plasma and plasma phospholipids. The amount of substitute fats represented, on average, 21% of total fat and 8% of total energy intake. Changes in the relative fatty acid composition of plasma phospholipids indicated further fatty acid metabolism, and were closely related to the serum cholesterol level. The reduction in saturated fatty acids led to a significant increase in the proportion of n-3 and n-6 polyunsaturated fatty acids (PUFA) with the rapeseed oil diet, whereas the margarine caused a significant rise in n-6 PUFA only. The increase in the proportions of the two PUFA families occurred in accordance with their competitive order, most completely with the rapeseed oil diet. When butter was replaced by rapeseed oil, low-density-lipoprotein-cholesterol decreased by an average of 9.1% without a reduction in high-density-lipoprotein-cholesterol. During margarine substitution the reduction was 5.2%, on average. Of the plasma phospholipids, alpha-linolenic acid and the linoleic:stearic acid ratio, but not oleic acid, were the components most significantly correlated with serum cholesterol levels or the decrease in these levels. The results show that rapeseed oil can act primarily as a source of essential fatty acids, rather than that of monoenes, in the diet of butter users.


Biochemical and immunological properties of urinary angiotensinase A and dipeptidylaminopeptidase IV. Their use as markers in patients with renal cell injury. Dipeptidyl peptidase IV (EC 3.4.14.5) and angiotensinase A (EC 4.4.11.7) were purified to homogeneity from pooled urine concentrate of patients with renal damage, using ultrafiltration, ammonium sulphate precipitation, lectin affinity chromatography, FPLC-ion-exchange(Mono-Q-)chromatography, and FPLC-gel filtration (Superdex). Based on the specific enzyme activity of the starting material, dipeptidyl peptidase IV was enriched 1629 fold, angiotensinase A 1183 fold. The relative molecular masses, Michaelis constants and isoelectric points were determined. Negative staining of the purified enzymes revealed globular proteins (5-7 nm). Antisera raised against dipeptidyl peptidase IV and angiotensinase A reacted specifically with tubular and, in the case of anti-angiotensinase A sera, with tubular and glomerular structures. In addition, urinary membrane vesicles of proximal tubule origin were eluted with the void volume (Superdex-gel filtration), indicating heavy epithelial cell disintegration. Both soluble tissue enzymes (dipeptidyl peptidase IV, angiotensinase A) and vacuolar blebs shed from epithelia contribute to proteinuria, as was shown in patients with glomerulonephritis, interstitial nephritis, diabetic nephropathy and, for angiotensinase A, in patients with essential arterial hypertension.


Effects of intracerebroventricular administration of D,L-2-amino-5-phosphonovaleric acid, an N-methyl-D-aspartate receptor antagonist, on luteininizing hormone release in ovariectomized lambs. To determine whether endogenous glutamate and aspartate control LH secretion via N-methyl-D-aspartate (NMDA) receptors in the sheep, we evaluated the effects of the NMDA receptor antagonist D,L-2-amino-5-phosphonovaleric acid (AP5) on secretion of LH in ovariectomized lambs. Twelve lambs were ovariectomized and surgically implanted with lateral cerebroventricular cannulae. At the time of the experiment, (38 wk of age) they received intracerebrally 4 injections of either 50 (n = 4), 100 (n = 4), or 200 micrograms (n = 4) of AP5. Blood samples were collected every 10 min for 8 h with animals receiving AP5 at hours 4, 5, 6, and 7. Patterns of LH during the preinjection period were compared to those during the period encompassing AP5 injections. Mean concentrations of LH were lower during AP5 injections than during the preinjection periods, a response that was not influenced by dose (0.87 +/- 0.08 vs. 0.69 +/- .07 ng/ml; p < 0.01). LH pulse amplitude decreased during AP5 treatment relative to the preinjection periods, but this difference was not statistically significant (0.79 +/- 0.11 vs. 0.68 +/- 0.10 ng/ml; p = 0.09). There were no effects of AP5 on LH pulse frequency (1.00 +/- 0.10 vs. 0.83 +/- 0.15 pulses/h for injection and preinjection periods; p > 0.10). A second experiment was done to evaluate a higher dose of AP5. Four animals were chosen to receive 4 injections of 2 mg of AP5 in a design identical to that used in the first experiment.


Biochemical characterization of phosphoinositide hydrolysis stimulated by 5-HT3 receptor agonists. Serotonin (5-HT) stimulates phosphoinositide (PI) turnover in rat fronto-cingulate cortical slices and is probably mediated through the activation of both 5-HT2 and 5-HT3 receptors. We have extended these findings and have assessed whether the increased stimulation of PI turnover is secondary to 5-HT stimulated arachidonate metabolism or to the release of another neurotransmitter. Incubation of the cortical slices by the two 5-HT3 receptor agonists, 2-methyl-serotonin (2-Me-5-HT) and phenylbiguanide (PBG), significantly decreases serotonin-stimulated phosphoinositide turnover, indicating that activation of 5-HT3, receptors by 2-Me-5-HT and PBG caused the desensitized PI hydrolysis to 5-HT. Indomethacin did not affect the increased PI hydrolysis induced by 5-HT, 2-Me-5-HT and PBG, suggesting that neither cyclooxygenase nor lipoxgenase activity is required for the PI response and that it is independent of arachidonic acid metabolism. The stimulation in PI turnover induced by 5-HT and the 5-HT3 receptor agonists was not potentiated by proteinase inhibitors suggesting that the release of a peptide neurotransmitter is not involved in the PI response. In addition, the effects of 5-HT, 2-Me-5-HT and PBG on PI turnover are additive to the effect of KCl and veratrine. In conclusion, our results indicate that the action of 2-Me-5-HT and PBG on PI turnover is direct.


Muscarinic inhibition of reticular thalamic cells by basal forebrain neurones. Pressure injections of a Ringer's solution containing glutamate (10 or 20 mM) into the nucleus basalis of Meynert inhibited the tonic firing of reticular thalamic (RT) neurones which were recorded in rats under deep urethane anaesthesia. When the inhibition was strong enough to stop the discharges, a burst firing mode was induced in RT cells before the recovery of tonic discharges. This glutamate-induced inhibition of RT cells was completely abolished following the systemic administration of the muscarinic antagonist, scopolamine (150 micrograms kg-1, i.v.). These results indicate that the cholinergic cells of the nucleus basalis of Meynert can control the mode of discharges of RT neurones through the activation of muscarinic receptors.


Chronic nicotine treatment decreases dopamine D2 agonist binding in the rat basal ganglia. To elucidate possible actions of nicotine on dopamine D2 receptor binding, the effect of chronic continuous (-)nicotine treatment (osmotic pumps s.c., 0.125 mg kg h-2, 14 days) was studied in the binding of [3H]N-propylnorapomorphine ([3H]NPA) and [125I]sulpride in coronal cryostat sections in the rat. Quantitative autoradiography showed that nicotine decreased the binding of [3H]NPA in the basal ganglia, preferentially in the nucleus accumbens and olfactory tubercle. In contrast, [125I]sulpride binding was not affected. Nicotine decreased the KD value of [3H]NPA by 27% and decreased the Bmax value by 17%, using filter-wiped sections. These results indicate that chronic continuous nicotine treatment affects the D2 receptor and that this effect may be involved in the development of nicotine dependence.


No association or linkage with HLA-DR or -DQ genes in south Indians with pulmonary tuberculosis. Studies of the HLA class II genes were performed in patients and multiple families with pulmonary tuberculosis from South India to seek any association of disease susceptibility with an individual allele or haplotype. TaqI RFLP analysis of HLA-DRB, -DQA and -DQB genes was done in 38 patients and 36 healthy control subjects. No significant association with any particular allele or haplotype was obtained. Linkage analysis performed in 12 families and haplotype sharing analysis in 9 families showed that the genetic susceptibility to pulmonary tuberculosis was not linked to the HLA region. The results suggest that the RFLP patterns of HLA class II genes DRB, DQA and DQB are not associated with susceptibility to pulmonary tuberculosis and that the genes controlling susceptibility or resistance may be located outside the HLA region.


[Multivisceral and extended resection in pancreatic cancer]. Out of 303 pancreatoduodenectomies performed for carcinoma in the past 19 years, 100 patients required a multivisceral or (in 39 cases) a regional pancreatectomy. Although the operative and hospital mortality for these extended resections was only 2%, long-term survival (only 1 patient survived more than 5 years) was inferior to conventional radical pancreatoduodenectomy with a 25% 5-year survival rate.


The role of Gln61 and Glu63 of Ras GTPases in their activation by NF1 and Ras GAP. Two distinct GAPs of 120 and 235 kDa called GAP1 and NF1 serve as attenuators of Ras, a member of GTP-dependent signal transducers, by stimulating its intrinsic guanosine triphosphatase (GTPase) activity. The GAP1 (also called Ras GAP) is highly specific for Ras and does not stimulate the intrinsic GTPase activity of Rap1 or Rho. Using GAP1C, the C-terminal GTPase activating domain (residues 720-1044) of bovine GAP1, we have shown previously that the GAP1 specificity is determined by the Ras domain (residues 61-65) where Gln61 plays the primary role. The corresponding domain (residues 1175-1531) of human NF1 (called NF1C), which shares only 26% sequence identity with the GAP1C, also activates Ras GTPases. In this article, we demonstrate that the NF1C, like the GAP1C, is highly specific for Ras and does not activate either Rap1 or Rho GTPases. Furthermore, using a series of chimeric Ras/Rap1 and mutated Ras GTPases, we show that Gln at position 61 of the GTPases primarily determines that NF1C as well as GAP1C activates Ras GTPases, but not Rap1 GTPases, and Glu at position 63 of the GTPases is required for maximizing the sensitivity of Ras GTPases to both NF1C and GAP1C. Interestingly, replacement of Glu63 of c-HaRas by Lys reduces its intrinsic GTPase activity and abolishes the GTPase activation by both NF1C and GAP1C. Thus, the potentiation of oncogenicity by Lys63 mutation of c-HaRas appears primarily to be due to the loss of its sensitivity to the two major Ras signal attenuators (NF1 and GAP1).


Antithyroid drug effects on function and growth of FRTL-5 cells. Although antithyroid drugs (ATDs) are known to exert their effects by inhibiting iodide organification within the thyroid follicular cell, a full understanding of their mechanisms of action is lacking. In this study the effects of methimazole (MMI) and propylthiouracil (PTU) on thyrotropin (TSH) and thyroid-stimulating immunoglobin (TSI)-stimulated cAMP production and growth in FRTL-5 cells was investigated. MMI, but not PTU, inhibited TSH-stimulated cAMP production, but only at the very highest concentration (10(-3) M): 0.3 +/- 0.01 vs 0.79 +/- 0.13 pmol/micrograms protein (p < 0.01). Neither MMI nor PTU inhibited TSI-stimulated cAMP production at any dose. Neither MMI nor PTU exhibited an inhibitory effect on TSH- or TSI-stimulated cell growth, as measured by [3H]-thymidine incorporation. These observations suggest that high concentrations of MMI may act to control thyroid function by inhibiting receptor-mediated cAMP production. Although decreases in thyroid gland size frequently occur during ATD therapy, neither MMI nor PTU exhibited any effect on TSH- or TSI-stimulated thyroid cell growth.


[The management of obstructive jaundice caused by pancreatic head carcinoma and periampullary carcinoma]. We had treated 115 patients with malignant obstructive jaundice, including 69 pancreatic head carcinoma and 46 periampullary carcinoma during the period between 1982 and 1991. In the 115 jaundiced patients 33 had undergone pancreaticoduodenectomy, 50 had bypass operation and the remaining 32 patients undergone percutaneous transhepatic biliary drainage (PTBD) only. No operative mortality happened for the 33 pancreaticoduodenectomies. Postoperative complications occurred in 12 patients. Leakage from the choledochojejunostomy was the most often occurred complications, it was found in 7 patients (21.2%). Intraabdominal abscesses happened in six patients (18.2%) which recovered by treating with ultrasound-guided catheteral drainage. Leakage from pancreaticojejunostomy was also found in five patients (15.2%), the complication recovered uneventfully after administration of total parenteral nutrition and good abdominal drainage. Twenty-two out 33 patients with pancreaticoduodenectomy received preoperative biliary drainage. However, despite preoperative biliary drainage, 10 of 22 patients (45.5%) still suffered postoperative complications. It implied that hyperbilirubinemia would trend to carry a high postoperative morbility. The prognosis for our patients with pancreatic head carcinoma was extremely poor. The mean survival period for all of them was not exceeding 12 months. Those who had PTBD as the sole treatment had the shortest survival period, which was 3.4 +/- 3.1 months only. On the other hand, the mean survival period for those who had periampullary cancer and had pancreaticoduodenectomy was 35.5 +/- 27.2 months, while it was 13.3 +/- 10.1 and 11.8 +/- 10.0 months for those having bypass operation and PTBD respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


[Indications and contraindications of digital replantation]. With the development of microsurgery, replantation surgery have become the method of choice in treating the digit amputations. Although better than 90% of successful rate can be achieved in replanting guillotine type amputation, the final functional recovery is the main goal. The indications include: (1) thumb amputations, (2) Zone I amputation, (3) multiple digits, (4) bilateral amputation, (5) hemi-hand amputations, (6) hand amputation at wrist to upper forearm, and (7) pediatric amputations. And the contraindications include: (1) life-threatening associated injuries, (2) technically impossible, and (3) self-inflicted injuries. As for condition which have been previously put in the contraindication categories, such as: (1) single finger amputation, (2) Zone II amputations, (3) severe crush or avulsion injuries, (4) geriatric amputations, and (5) lengthy ischemia time amputations, the decision of to replant or not to replant was not a straight forward one. The decisions are individualized to meet the needs of different patients.


[Risk factors of lung cancer].

[Risk factors of lung cancer]. The relationship between various risk factors and lung cancer was evaluated in a case-control study. One hundred and forty-one cancer patients newly cytologically or pathologically diagnosed from May 1990 to July 1991 at Tri-Service General Hospital (TSGH) were recruited as cases. Two control groups were also studied: 282 hospital controls two-to-one matched with cases on sex, age, hospital of admission and insurance status were selected from the TSGH Ophthalmologic Department, and 282 neighborhood controls two-to-one matched on sex, age, and residence were randomly selected from eligible neighbors. A comparison of interview data between cases and hospital controls based on multiple conditional logistic regression revealed that cigarette smoking, keeping doves as pet, occupational exposure to cotton dust and working as a cook were risk factors for lung cancer. An inverse association between incense burning and lung cancer was noted. The comparison between cases and neighborhood controls showed lung cancer was significantly associated with cigarette smoking, keeping doves, prior chronic bronchitis, occupational exposure to cotton dust, asbestos and radiation, low frequency of burning incense, and low intake of vitamin A derived from vegetables and fruits. There was no association between lung cancer and working as a cook when cases were compared with neighborhood controls.


[Sleep quality and nocturnal hypoxemia in patients with chronic obstructive pulmonary disease]. To evaluate the incidence of sleep apnea syndrome (SAS), oxygen desaturation during sleep and sleep quality in patients with chronic obstructive pulmonary disease (COPD), 30 COPD patients and 20 healthy snorers (without SAS) were studied. Each subject received a pulmonary function test (PFT) (simple spirometry), arterial blood gas determination and an overnight sleep study. COPD patients were divided into two groups: those with SAS (group I) and those without (group II). Group II patients were further subdivided into: group IIa [delta SaO2 < 15% (delta SaO2 = baseline SaO2-lowest SaO2) and group IIb (delta SaO2 > or = 15%); group IIc (baseline SaO2 > 90%) and group IId (baseline SaO2 < or = 90%). Our results showed that only six of 30 (20%) COPD patients had an associated SAS. Among group II patients, the lowest SaO2 and delta SaO2 were correlated with baseline SaO2, PaO2 and PaCO2 but were not correlated with age, % of ideal body weight, FVC, FEVl, FEVl/FVC. Group IIb patients (n = 10) had a lower SaO2 during sleep, a lower baseline PaO2, and a lower hematocrit level than group IIa patients (n = 14). Group IId patients (n = 9) had a lower PaO2 and a higher delta SaO2 during sleep than group IIc patients (n = 15). However, there were no significant differences in age, percent of ideal body weight (IBW), FVC, FEVl or FEVl/FVC values between groups IIa and IIb, or between groups IIc and IId. Group II patients had a lower percentage of sleep efficiency, higher arousal and movement indices and a longer period of stage 1 sleep, compared to the control group. In conclusion, the incidence of COPD patients with SAS is 20%. Age, percentage of IBW, FEVl, and FEVl/FVC values are not reliable predictors of the risk of nocturnal hypoxemia among COPD patients. However, a possible correlation between baseline SaO2, PaO2 and PaCO2 values and the incidence of nocturnal hypoxemia exists. Finally, COPD patients experienced a poorer quality of sleep in comparison with the control group.


[Preliminary study of cartilage repair with autologous periosteum and fibrin adhesive system]. The potential surgical transplantation with autogenous periosteal grafts and Fibrin Adhesive System (FAS) was attempted in a rabbit model. The grafts were taken from the tibia, transplanted and fixed with FAS to artificial full-thickness (0.4 x 0.3 cm) defect on the femoral condyle. Histologic and ultrastructural findings revealed chondrocyte regeneration in the control, grafted, and graft/FAS treated group at week 6; however, chondrogenesis of the reparative tissue was best demonstrated in the graft/FAS group. At week 12, the interface between the reparative tissue and the surrounding tissue was invisible in the FAS/graft group, as compared with the well-defined interface in the grafted group and the control. The results strongly suggest that FAS-treated periosteal transplant is a potential model for the repair of articular cartilage defects. Although the results are preliminary, all seem promising in the clinical aspects.


[Effect of fibrin on nerve regeneration in a silicone chamber]. When regenerating from an injury, fluid containing nerve growth-promoting components such as the nerve growth factor (NGF) will accumulate around the stump of a cut nerve within 24 hours. It has been found that this fluid also contains fibrin. To evaluate the effect of fibrin on nerve regeneration, we cut both facial nerves of 40 guinea pigs and sutured both ends of the nerve stumps to silicone tubes. The distance between the stumps were kept at around 8 mm in the silicone chamber. Autogenous fibrin isolated from the blood of each guinea pig was injected into the silicone chamber on the left side, while lactate Ringer's solution was injected into the silicone chamber on the right side as a control. The status of nerve regeneration in both sides of the silicone chambers were later evaluated at 3 and 5 weeks. Histological study revealed that after regeneration for 3 weeks, the total axon number and the fascicular number increased significantly in the fibrin-filled chamber. However, after 5 weeks, there was no significant difference in nerve regeneration between the two groups.


[Influence of haloperidol on plasma Li+ and Li+ index]. Since Cohen and Cohen reported four cases suffering from irreversible brain damage after combined use of haloperidol and lithium, the possible toxic interaction between these two drugs has been intensively studied. The results are controversial. In this study, we used the within-Ss design to study the influence of haloperidol on the plasma Li+ level and Li+ index in 29 manic patients. Also, we used the in vitro method to study the influence of haloperidol on the Li+ index in 36 healthy volunteers. Haloperidol significantly increased the plasma Li+ levels (paired t test, t = 2.797, d.f. = 27, p < 0.01) in the in vivo study, but did not alter the Li+ index in either the in vivo or the in vitro study.


[Parathyroid storm: report of two cases]. Parathyroid storm in patients with primary hyperparathyroidism has previously been described as hyperparathyroid crisis, parathyroid intoxication or acute hyperparathyroidism. Whatever the nomenclature, all emphasize the severity and urgency of this disease entity. Although fewer than 200 cases have been described since the first report by Dawson in 1932, it is generally agreed that parathyroid storm is more prevalent than commonly appreciated. The symptoms and signs of the syndrome are not only due to the hypercalcemia, but also to the toxic effects of the parathyroid hormone (PTH). Its wide, but nonspecific clinical presentations make it easily confused with other cardiovascular or renal diseases. The mortality rate in untreated cases of parathyroid storm is essentially 100%. With combined medical-surgical treatment, it is still reported to be as high as 40%. Two patients with parathyroid storm were encountered at our institute recently, they both presented with severe hypercalcemia, consciousness disturbance and acute renal failure. The serum level of the intact form of PTH (iPTH) in both patients was greater than 1,000 pg/mL. Case 1, a 63-year-old female, presented with hypercalcemic crisis. Initially, good responsiveness to a saline infusion, steroids and furosemide administration was noted. Unfortunately, she became comatous after fine-needle aspiration of the parathyroid tumor. The recurrent storm was refractory to medical therapy, but was treated successfully by surgical removal of the single adenoma. This is a rare reported case regarding a hyperparathyroid storm after fine-needle aspiration of a parathyroid adenoma.(ABSTRACT TRUNCATED AT 250 WORDS)


Resistance of chronic lymphocytic leukaemia cells to interferon-alpha generated lymphokine activated killer cells. Recent studies have shown that, when used in early stage disease, interferon-alpha (IFN-alpha) can produce a fall in the number of malignant cells in the peripheral blood of patients with B-CLL. In this study, we investigated the effect of IFN-alpha on natural killer (NK) cell and lymphokine-activated cell (LAK) activity in patients with B-CLL. In vitro, IFN-alpha (500 U/ml for 18 hours) induced LAK activity in patients with B-CLL (27.7 +/- 9.9%, n = 20), and IL-2 (500 U/ml for 5 days) produced similar activity (35.9 +/- 8.8%, n = 7). Despite the induction of LAK activity by IFN-alpha and IL2 in patients with B-CLL, the malignant cells remained resistant to both allogeneic and autologous LAK effectors. NK activity in patients with B-CLL is also low (23.1 +/- 7.2%, n = 20), and B-CLL cells were resistant to NK cell activity. In cold target competition assays, CLL cells did not compete with labelled K562 or Daudi targets in the NK and LAK assays, suggesting that the malignant cells are not recognised by the effector cells, and this may be related to low level of expression of the adhesion receptors, LFA-1 and ICAM-1. Finally, CLL cells were also resistant to antibody dependent cell mediated cytotoxicity, but were susceptible to antibody dependent complement mediated lysis. These results suggest that it is unlikely that the effects of IFN-alpha in B-CLL are due to the enhancement of NK or LAK activity.


Demonstration of HTLV-related proviral DNA sequences and antibodies reactive with HTLV internal proteins in an Hungarian patient with Sézary syndrome. DNA sequences distantly related to the proviral DNA of HTLV-I were found in the leukemic cells of a Hungarian patient suffering from Sézary syndrome. Serum samples from the patient contained antibodies reactive with the internal core polypeptides of HTLV-I and HTLV-II, but not with the env gene encoded type-specific HTLV antigens. The husband and daughter of the patient also had antibodies of the same specificity. These findings suggest the presence of a virus distantly related to HTLV-I and HTLV-II.


Autologous blood stem cell transplantation in malignant lymphomas: an Italian Cooperative Study. Twenty-three patients with malignant lymphoma, (7 Hodgkin's, and 16 non-Hodgkin's) in different phases of disease were autografted in 4 Italian Haematology institutions using only chemotherapy-mobilized blood stem cells (BSC) collected by apheresis. Clinical and laboratory data were analysed centrally and showed mean collection yields of 8.1 x 10(8) kg mononuclear cells (MNC) (SE 0.5; range 2.6-13.8) and 24.1 x 10(4) kg CFU-GM (SE 7.4; range 1.4-162.9). The mean times required to attain 0.5 x 10(9)/l neutrophils and 50 x 10(9)/l platelets after marrow-ablative high-dose chemo+radiotherapy and BSC reinfusion were 14.9 days (SE 1.5; range 7-38) and 18.6 days (SE 2.6; range 6-49) respectively. The incidence of early deaths was < 5% and the requirement for support with blood product transfusion was moderate. The progression free survival (PFS) is > 50% at 3 years with a median follow-up of 17.3 months. Results were significantly better for patients autografted in remission. These results suggest that autologous blood stem cell transplantation (ABSCT) may be proposed for the primary treatment of poor prognosis malignant lymphomas. However, ABSCT needs to be compared with autologous bone marrow transplantation (ABMT) followed by infusion of growth factors to accelerate recovery.


Expression and functional role of CD54/Intercellular Adhesion Molecule-1 (ICAM-1) on human blood cells. CD54/Intercellular Adhesion Molecule-1 (ICAM-1) is a cell adhesion molecule largely distributed among normal and neoplastic tissues. Through the binding to its ligand(s) CD54 plays a key role in cell to cell interactions leading to the immune response. Recently, CD54 expression has been investigated on hematopoietic cells: the antigen is predominantly expressed in the early stages of normal hematopoiesis and during the activation of blood cells. As regards to hematological malignancies, CD54 is strongly expressed on neoplastic cells from "stem cell derived" neoplasms. In AML, CD54 expression is related with other differentiation-linked molecules such as CD34 and HLA-DR and is significantly correlated with FAB morphological classification. In lymphoproliferative disorders, a high CD54 expression is associated with germinal centre lymphomas. This review summarizes our current understanding of CD54 with emphasis on recent advances and reference to unresolved issues such as its prognostic role in the clinical outcome of oncohematological diseases.


Effect of serotonergic agents on regional concentrations of somatostatin- and neuropeptide Y-like immunoreactivities in rat brain. A possible role for neuropeptides in affective disorders is suggested by many investigators. Somatostatin-like immunoreactivity (SS-LI) and neuropeptide Y-like immunoreactivity (NPY-LI) concentrations are demonstrated to be reduced in cerebrospinal fluid from depressed patients. We have shown that long-term treatment with serotonin uptake inhibitors, clomipramine and zimelidine, reduce brain SS-LI concentrations in the rat. We have studied the effect of serotonergic agents on regional brain SS-LI and NPY-LI concentrations in rats. Long-term treatment with 5-hydroxytryptamine (5-HTP), a serotonin precursor, caused reductions in SS- and NPY-LI levels in the hypothalamus. SS- and NPY-LI concentrations in the brain were markedly elevated by treatment with p-chlorophenylalanine, a serotonin synthesis inhibitor. Intracerebroventricular administration of 5,7-dihydroxytryptamine, a serotonin neurotoxin, resulted in elevations of both peptides in the brain. These results suggest a inhibitory role for the serotonergic system in the brain in the regulation of SS and NPY.


Protection from 1-methyl-4-phenylpyridinium (MPP+) toxicity and stimulation of regrowth of MPP(+)-damaged dopaminergic fibers by treatment of mesencephalic cultures with EGF and basic FGF. Several peptide growth factors can maintain survival or promote recovery of injured central neurons. In the present study, the effects of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on the toxicity produced by the dopaminergic neurotoxin, 1-methyl-4-phenylpyridinium (MPP+), were investigated in rat mesencephalic dopaminergic neurons in culture. High affinity [3H]DA uptake and morphometric analyses of tyrosine hydroxylase immunostained neurons were used to assess the extent of MPP+ toxicity, dopaminergic neuronal survival and growth of neurites. Consistent with previous reports, EGF and bFGF treatments stimulated neuritic outgrowth in dopaminergic neurons, increased DA uptake and enhanced their long-term survival in vitro. These growth factors also stimulated proliferation of astrocytes. The time course of EGF and bFGF effects on dopaminergic neurons coincided with the increase in glial cell density, suggesting that proliferation of glia mediates their trophic effects. Several findings from our study support this possibility. When MPP+ was applied to cultures at 4 days in vitro, before glial cells had proliferated, the damage to dopaminergic neurons was not affected by EGF or bFGF pretreatments. However, when cultures maintained in the presence of the growth factors for 10 days were exposed to MPP+, after they had become confluent with dividing glial cells, the MPP(+)-induced decreases in DA uptake and cell survival were significantly attenuated. Furthermore, when glial cell proliferation was inhibited by 5-fluoro-2'-deoxyuridine, the protective effects of EGF and bFGF against MPP+ toxicity were abolished. Continuous treatment of MPP(+)-exposed cultures with EGF or bFGF resulted in the stimulation of process regrowth of damaged dopaminergic neurons with concomitant recovery of DA uptake, suggesting that the injured neurons are able to respond to the trophic effects of EGF and bFGF. In summary, our study shows that the trophic effects of EGF and bFGF on mesencephalic dopaminergic neurons include protection from the toxicity produced by MPP+ and promotion of recovery of MPP(+)-damaged neurons. Stimulation of glial cell proliferation is necessary for these effects.


Lipogenesis in turkeys and chickens: a study of body composition and liver lipogenic enzyme activities. 1. Carcase composition, fat deposition and the activities of three liver lipogenic enzymes were compared in turkeys and chickens fed ad libitum on two different isocaloric diets, respectively adapted to chickens (C) and to turkeys (T). Diets differed in their protein content, being higher by 60 g/kg in diet T. 2. Chickens were much fatter than turkeys and exhibited higher activities of acetyl-coenzyme A carboxylase (EC 6.4.1.2) and malic enzyme (EC 1.1.1.40). 3. The carcase composition of turkeys was not influenced by the type of diet administered, while chickens fed on diet C were fatter than chickens fed on diet T. Compared to diet T, diet C enhanced malic enzyme activity, whatever the species and age. 4. A good correlation between abdominal fat and total fatness was observed in both species but especially in turkeys. 5. In conclusion, hepatic lipogenesis is much lower in turkeys than in chickens.


Role of the sympathetic nervous system in the alcohol-guanabenz hemodynamic interaction. The present study evaluated the contribution of the sympathetic nervous system to the adverse hemodynamic action of ethanol on hypotensive responses in conscious unrestrained spontaneously hypertensive rats. Ethanol caused a dose-related attenuation of the hypotensive effect of guanabenz. An equivalent hypotensive response to sodium nitroprusside was not influenced by ethanol, which indicates a potential specific interaction between ethanol and guanabenz. Alternatively, it is possible that a preexisting high sympathetic nervous system activity, which occurred during nitroprusside infusion, may mask a sympathoexcitatory action of ethanol. Further, ethanol (1 g/kg) failed to reverse the hypotensive effect of the ganglionic blocker hexamethonium. This suggests that a centrally mediated sympathoexcitatory action of ethanol is involved, at least partly, in the reversal of hypotension. In addition, the antagonistic interaction between ethanol and guanabenz seems to take place within the central nervous system and involves opposite effects on central sympathetic tone. Finally, changes in plasma catecholamines provide supportive evidence for the involvement of the sympathetic nervous system in this interaction. In a separate group of conscious spontaneously hypertensive rats, ethanol (1 g/kg) reversed the guanabenz-evoked decreases in blood pressure and plasma catecholamine levels. It is concluded that (i) ethanol adversely interacts with centrally acting antihypertensive drugs through a mechanism that involves a directionally opposite effect on sympathetic activity, and (ii) a sympathetically mediated pressor effect of ethanol is enhanced in the presence of an inhibited central sympathetic tone.


Inhibition of nitrovasodilator- and acetylcholine-induced relaxation and cyclic GMP accumulation by the cytochrome P-450 substrate, 7-ethoxyresorufin. We examined the effect of the cytochrome P-450 substrate, 7-ethoxyresorufin (7-ER), and its corresponding product, resorufin, on nitrovasodilator- and endothelium-dependent relaxation of isolated rat aorta. The EC50 value for glyceryl trinitrate (GTN) induced relaxation was increased over 100-fold by 7-ER and less than 3-fold by resorufin. The EC50 value for sodium nitroprusside (SNP) induced relaxation was increased approximately 12-fold by 7-ER, acetylcholine (ACh) induced relaxation was abolished, and relaxation induced by isopropylnorepinephrine was not significantly affected. GTN-, SNP-, and ACh-induced increases in cyclic GMP accumulation were inhibited by 7-ER, as were basal cyclic GMP levels in endothelium-intact, but not endothelium-denuded tissues. 7-ER decreased GTN biotransformation in intact aorta and decreased the regioselective formation of glyceryl-1,2-dinitrate. The activation by GTN and SNP of aortic guanylyl cyclase in broken cell preparations was not affected by 7-ER, indicating that the inhibitory effect of 7-ER is probably not due to a direct interaction with guanylyl cyclase. The inhibitory effect of 7-ER on GTN-induced relaxation was not altered by the addition of superoxide dismutase, suggesting that 7-ER does not act by increasing superoxide anion concentration (which would serve to increase the degradation of nitric oxide (NO) formed during vascular GTN biotransformation). Our data provide further evidence for the role of the cytochrome P-450--cytochrome P-450 reductase system in the biotransformation of GTN to an activator (presumably nitric oxide) of guanylyl cyclase. The data are consistent with a mode of action of 7-ER involving either competitive inhibition of vascular cytochrome P-450 or uncoupling of vascular cytochrome P-450 reductase from cytochrome P-450. The data also suggest that the cytochrome P-450 system facilitates NO release from SNP and that 7-ER has an inhibitory effect on endothelial nitric oxide synthase.


A 9.6 kilobase deletion in the low density lipoprotein receptor gene in Norwegian familial hypercholesterolemia subjects. Haplotype analysis of the low density lipoprotein receptor (LDLR) gene was performed in Norwegian subjects heterozygous for familial hypercholesterolemia (FH). Southern blot analysis of genomic DNA, using an exon 18 specific probe and the restriction enzyme NcoI, showed that two out of 57 unrelated FH subjects had an abnormal 3.6 kb band. Further analyses revealed that this abnormal band was due to a 9.6 kb deletion that included exons 16 and 17. The 5' deletion breakpoint was after 245 bp of intron 15, and the 3' deletion breakpoint was in exon 18 after nucleotide 3390 of cDNA. Thus, both the membrane-spanning and cytoplasmatic domains of the receptor had been deleted. A polymerase chain reaction (PCR) method was developed to identify this deletion among other Norwegian FH subjects. As a result of this screening one additional subject was found out of 124 subjects screened. Thus, three out of 181 (1.7%) unrelated Norwegian FH subject possessed this deletion. The deletion was found on the same haplotype in the three unrelated subjects, suggesting a common mutagenic event. The deletion is identical to a deletion (FH-Helsinki) that is very common among Finnish FH subjects. However, it is not yet known whether the mutations evolved separately in the two countries.


Genotyping of spinal muscular atrophy families with linked DNA probes. We report on linkage analysis and haplotype characterization in 40 Italian families with spinal muscular atrophy (SMA). The investigated loci included D5S6, D5S112, D5S39, and D5S76. No evidence of unlinked families was found. Thirty-two (80%) of the examined families were fully informative for prenatal diagnosis and carrier detection. The frequencies of individual alleles did not differ between SMA and normal chromosomes.


Induction of P-450 cytochromes 2E2, 1A1, and 1A2 by imidazole in neonatal rabbits. Cytochrome P-450 2E1 is induced in adult rabbits by treatment with alcohol, imidazole, and a variety of other agents, as shown earlier in this laboratory, but it is not known whether the highly homologous P-450 2E2 is similarly induced. In this study, the effects of imidazole on 2E2 expression were examined in neonatal rabbits, in which 2E1 is not detectable. Treatment of the animals with imidazole on days 8 through 11 after birth caused a 3-fold increase in the content of total P-450 in liver microsomes. In contrast, the microsomal content of cytochrome b5 and NADPH-P450 reductase was not changed. Immunoblot analysis revealed a significant increase in the level of P-450 2E2 (3-fold) as well as 1A1 (> 10-fold) and 1A2 (> 2-fold) in hepatic microsomes from imidazole-treated neonatal rabbits. The rates of microsomal N-demethylation of N-nitrosodimethylamine and O-deethylation of 7-ethoxyresorufin were similarly increased from 1.3 and 0.03 nmol/min/mg protein, respectively, to 5.6 and 0.24 nmol/min/mg protein, respectively, by imidazole treatment. Blot analysis indicated that the levels of 2E2, 1A1, and 1A2 mRNAs are not increased by imidazole treatment and that 2E1 mRNA is not detectable in either untreated or imidazole-treated neonates. The induction of P-450 2E2 was confirmed by NH2-terminal amino acid sequence analysis of immunopurified 2E protein from hepatic microsomes of imidazole-treated neonatal rabbits.(ABSTRACT TRUNCATED AT 250 WORDS)


Phenobarbital and dexamethasone induce expression of cytochrome P-450 genes from subfamilies IIB, IIC, and IIIA in mouse liver. Phenobarbital (PB) and dexamethasone (DEX) induce several liver-specific cytochrome P-450 mRNAs in rats. We examined the induction of P-450 mRNAs from families IIB, IIC, and IIIA by PB and DEX in six inbred mouse strains. P-450IIB1-related mRNA species were induced 3- to 13-fold by PB and 3- to 15-fold by DEX in all animals. P-450IIC6-related mRNA species were induced 3- to 7-fold by PB in males and females, and up to 5-fold by DEX in most males but not in female mice, in which DEX was inactive. P-450IIIA-related mRNA species were induced 2- to 7-fold by PB and 2- to 20-fold by DEX in all animals of either sex. In DBA/2J female mice, both inducers triggered a comparable early response (4 hr) at a low dose (10 mg/kg) for all three gene subfamilies, the maximum being reached between 8 and 18 hr of treatment with 100 mg/kg. Under the optimal induction conditions, coadministration of PB and DEX did not lead to any further increase in the responses. These results demonstrate the existence of analogies, as well as striking differences in the inductive effects of PB and DEX between rats and mice. They also indicate the possible involvement of these inducers in related inductive pathways for three cytochrome P-450 gene subfamilies in mouse liver.


Cyclosporin A metabolism in human liver, kidney, and intestine slices. Comparison to rat and dog slices and human cell lines. This study assesses the contribution of cyclosporin A (CsA) metabolism at sites of CsA-induced toxicity: kidney and liver, and a site of absorption, the intestine. With organ slice cultures (8 mm phi), it has been possible to demonstrate that the extrahepatic metabolism of CsA is significant. Both human kidney and colonic mucosal tissue metabolize CsA (1 microM, 24 hr) as analyzed by HPLC. The major metabolite M17 was formed in the kidney at an initial rate of 3 pmol/hr/mg slice protein, which was comparable to M17 formation in the liver slices (5 pmol/hr/mg slice protein). The rate of total CsA metabolism by human kidney slices represents about 42% the rate in liver slices. The metabolism of CsA to M17 was the same in the human kidney cell line 293; however, CsA metabolism was not detectable using human kidney microsomes, nor was metabolism clearly evident in either rat or dog kidney slice cultures. The metabolism of CsA by human colonic mucosal slices to at least three metabolites and the metabolism of CsA by the human intestinal cell line FHs74 Int indicates that the intestinal metabolism of CsA contributes to the first-pass effect of the drug. The liver proved to be the major site of CsA biotransformation in terms of the complexity of metabolites produced, whereas the human liver HepG2 cell line proved not to be a suitable model for CsA metabolism. A time course revealed that the first metabolites formed in the liver slice cultures were the monohydroxylated, M1 and M17, and N-demethylated, M21, followed by the secondary metabolites (including M8, M13, and M18).(ABSTRACT TRUNCATED AT 250 WORDS)


Pharmacokinetics and pharmacodynamics of valproate analogs in rats. III. Pharmacokinetics of valproic acid, cyclohexanecarboxylic acid, and 1-methyl-1-cyclohexanecarboxylic acid in the bile-exteriorized rat. The pharmacokinetics of valproic acid (VPA) and its structural analogs cyclohexanecarboxylic acid (CCA) and 1-methyl-1-cyclohexanecarboxylic acid (MCCA) were examined in bile-exteriorized rats. A 0.52 mmol/kg dose (equivalent to 75 mg/kg VPA) of test compound (N = 4 rats per compound) was administered as an intravenous bolus. VPA, CCA, and MCCA concentrations in serum, bile, and urine were determined by gas chromatography before and after incubation in sodium hydroxide to hydrolyze base-labile conjugates. Concentration-time profiles of these compounds in serum displayed apparent Michaelis-Menten kinetics. Serum concentrations of base-labile conjugates were similar to parent concentrations for VPA, were an order of magnitude lower than parent concentrations for CCA, and were undetectable for MCCA. Urinary recovery of base-labile (apparently glucuronide) conjugates in the bile-exteriorized rat was 28.8%, 12.0%, and 25.2% of the administered dose for VPA, CCA, and MCCA, respectively. In contrast, more than 50% of the dose for VPA and MCCA was recovered in bile as the base-labile conjugate, with less than 5% of the CCA dose recovered via this excretory route. Bile flow was stimulated significantly by VPA and MCCA, but not by CCA; changes in bile flow correlated with the biliary excretion rate of base-labile conjugates rather than with excretion of the parent compounds themselves.(ABSTRACT TRUNCATED AT 250 WORDS)


Metabolism of 3-tert-butyl-4-hydroxyanisole by horseradish peroxidase and hydrogen peroxide. 3-Tert-butyl-4-hydroxyanisole (3-BHA) was metabolized in the presence of horseradish peroxidase and hydrogen peroxide to 2-tert-butyl-p-benzoquinone (TBQ), 2,3-epoxy-5-tert-butyl-1,4-benzoquinone (TBQ-epoxide), and two known dimers. The formation of TBQ from 3-BHA required both horseradish peroxidase and hydrogen peroxide. When 2.5 mM 3-BHA was incubated with horseradish peroxidase and hydrogen peroxide, the formation of TBQ increased with hydrogen peroxide concentration up to 5 mM and decreased gradually at higher concentrations of hydrogen peroxide. On the other hand, the formation of TBQ-epoxide from 3-BHA increased, depending on hydrogen peroxide concentration at higher concentrations than 1 mM. In incubating 2-tert-butylhydroquinone (TBHQ) with horseradish peroxidase and hydrogen peroxide, TBHQ was rapidly oxidized to TBQ, and then TBQ-epoxide was also produced at concentrations more than 2.5 mM of hydrogen peroxide. In the absence of horseradish peroxidase, the incubation of TBQ with hydrogen peroxide resulted in TBQ-epoxide production. These results suggest that 3-BHA is metabolized to TBHQ, which is rapidly oxidized to TBQ, by horseradish peroxidase and hydrogen peroxide, and then TBQ is converted to TBQ-epoxide by only hydrogen peroxide.


Pharmacokinetic profile of theophylline in isolated perfused liver of rabbits at different ages. Development of drug-metabolizing activity during ontogenesis. The ontogeny of the biotransformation of exogenous and endogenous compounds has been mostly studied using liver cells and microsomal fractions. We have used liver perfusion for the first time to characterize the development of the total P-450 cytochrome-dependent system in the rabbit, with theophylline (TH) as tool substance. Livers of 0- to 60-day-old rabbits were perfused with TH (10 micrograms/ml) for 3 hr. Metabolizing enzymes (cytochrome P-450), ATP, glutathione, and glycogen were measured in liver tissue after perfusion. Lactate dehydrogenase, glutamic-oxalacetic transaminase, glucose, and urea were assayed in the medium throughout perfusion. The pharmacokinetic profile of TH was determined. The activity of total cytochrome P-450, as well as the intrinsic unbound clearance and TH metabolites production, increased following a similar sigmoidal pattern and reached a plateau around 30-45 days of the postnatal development of rabbit liver. The perfused tissue showed no signs of age-related hepatic damage or toxic effects of TH. Thus, the results in perfused liver predict its metabolic capacity during ontogenesis.


Simultaneous modeling of the pharmacokinetic and pharmacodynamic properties of enalkiren (Abbott-64662, a new renin inhibitor). I: Single dose study. This study describes the relationship between the measured effects (angiotensin I and renal plasma flow) and plasma drug levels using a combined pharmacokinetic-pharmacodynamic model after 90 min iv infusion of enalkiren in 15 healthy, salt-depleted subjects. Doses from 0.002 to 0.512 mg/kg were evaluated. One hour prior to enalkiren dosing, para-aminohippuric acid infusion was started for each subject and continued until 3 hr after the start of enalkiren infusion. Timed blood samples were obtained to measure enalkiren, para-aminohippuric acid, and angiotensin I levels in plasma. Enalkiren-induced effect changes lagged in time behind the plasma enalkiren level changes, showing a counterclockwise hysteresis loop. To relate the temporal relationship of effect changes accurately to plasma drug levels, a pharmacokinetic model was combined with a pharmacokinetic model that incorporated a hypothetical effect compartment. The magnitude of the time lag was quantified by the half-time of equilibration between concentrations in the hypothetical effect compartment and the plasma enalkiren levels (t1/2keo). The t1/2keo for angiotensin I (0.002 hr) is significantly shorter than that of renal plasma flow (0.267 hr), indicating that enalkiren equilibrates more rapidly with the angiotensin I-related effect compartment than the renal plasma flow-related effect compartment. Moreover, the model allows for estimation of the effect site concentration that causes one-half of the maximal predicted effect (EC50), which is a measure of an individual's sensitivity to enalkiren. The EC50 of angiotensin I (81.1 ng/ml) is substantially lower than that of renal plasma flow (4414 ng/ml), indicating that angiotensin I may be a more sensitive measure of enalkiren effects than renal plasma flow.


Characterization of metabolites of xylazine produced in vivo and in vitro by LC/MS/MS and by GC/MS. The metabolic fate of xylazine, 2-(2,6-dimethylphenylamino)-5,6-dihydro-4H-1,3-thiazine, in horses is described. The major metabolites identified in the hydrolyzed horse urine were 2-(4'-hydroxy-2',6'-dimethylphenylamino)-5,6-dihydro-4H-1,3-thiazi ne, 2-(3'-hydroxy-2',6'-dimethylphenylamino)-5,6-dihydro-4H-1,3-thiazi ne, N-(2,6-dimethylphenyl)thiourea, and 2-(2',6'-dimethylphenylamino)-4-oxo-5,6-dihydro-1,3-thiazine. These metabolites were also produced by incubating xylazine with rat liver microsomes. The major metabolite produced in vitro by rat liver preparations was found to be the ring opened N-(2,6-dimethylphenyl)thiourea. The identities of these metabolites were confirmed by spectroscopic comparisons with synthetic standards. Phenolic metabolic standards were synthesized efficiently by the use of Fenton's reagent. This reagent was used to monohydroxylate multiply substituted aromatic ring systems. LC/MS/MS, with an atmospheric pressure chemical ionization source, was found to be particularly useful in confirming the presence of phenolic metabolites in hydrolyzed equine urine and microsomal extracts. These phenolic metabolites could not be analyzed by GC/MS even after derivatization with silylating agents. The advantage of LC/MS/MS was that no or little sample preparation of urine or microsomal extract was necessary prior to the analysis. A mechanism is also proposed for the formation of the major metabolite, N-(2,6-dimethylphenyl)thiourea, from xylazine.


Stereoselective sulfoxidation by human flavin-containing monooxygenase. Evidence for catalytic diversity between hepatic, renal, and fetal forms. The stereoselective formation of p-tolyl methyl sulfoxide from the corresponding sulfide has been examined in detergent-solubilized human adult liver, adult kidney, and fetal liver microsomes, in order to compare the functional activities of human flavin-containing monooxygenase(s). Solubilization with detergent was performed to eradicate the contribution that cytochrome P-450 would make to the net stereochemistry. Consistent with studies in experimental animal livers, solubilized human fetal liver and adult kidney microsomes formed (R)-p-tolyl methyl sulfoxide in greater than 86% enantiomeric excess. These enzyme activities were sensitive to methimazole inhibition and were markedly thermolabile in the absence of NADPH, attributes that are consistent with a flavin-containing monooxygenase-mediated process. However, solubilized adult human liver microsomes displayed little stereoselectivity (0-40% enantiomeric excess) for the formation of (R)-p-tolyl methyl sulfoxide, although this reaction also displayed several of the characteristics of a flavin-containing monooxygenase-dependent process, including sensitivity to methimazole inhibition and NADPH protection against heat inactivation. Furthermore, this lack of stereoselectivity was not attenuated by the inclusion of activated oxygen scavengers in reaction mixtures. Human tissue metabolite profiling was further studied by using the ethyl, propyl, and isopropyl p-tolyl sulfides. Parallel changes in product stereochemistry as a function of increasing steric bulk were observed with the fetal liver and adult kidney tissue, whereas an anomalous profile was again observed with adult human liver. These data are consistent with the presence of functionally discrete complements of the flavin-containing monooxygenase in detergent-solubilized adult and fetal human liver microsomes.


Pharmacokinetics of oral methamphetamine and effects of repeated daily dosing in humans. The pharmacokinetics of orally administered S-(+)-methamphetamine-d3 were investigated in human male volunteers before and after a 13-day course of a slow release form of S-methamphetamine hydrochloride. A one-compartment pharmacokinetic model incorporating a lag time fits the data best. The average elimination half-life was 10.1 hr (range of 6.4-15.1 hr). There were no statistically significant differences in pharmacokinetic parameters when a low dose (0.125 mg/kg) was given before and after the 13-day oral regimen. When a higher challenge dose (0.250 mg/kg) was used, the maximum plasma concentration of methamphetamine-d3 was slightly but significantly greater when the test dose was given at the end of the oral dosing period than when it was given at the beginning. Although minor differences in pharmacokinetics occur after subchronic treatment with low doses of methamphetamine, their result would be to increase plasma concentration of the drug. Therefore, development of pharmacodynamic tolerance to methamphetamine could not be explained on the grounds of a change in pharmacokinetics.


Pharmacokinetic analysis of the metabolism of cocaine to norcocaine and N-hydroxynorcocaine in mice. Cocaine is hepatotoxic in humans and is a very effective hepatotoxin in the mouse. Previous in vitro studies have shown that the mixed function oxidase system is very important in the metabolism of cocaine to the hepatotoxic species. Activation of cocaine to the cytotoxic species is thought to proceed through the N-demethylation and subsequent N-hydroxylation of the bridgehead amine. The in vivo metabolism of cocaine involves not only oxidative but also hydrolytic mechanisms. Therefore the principle aim of this study was to establish a system in which the in vivo metabolism of cocaine to norcocaine and N-hydroxynorcocaine could be determined. The in vivo metabolism of acutely administered cocaine to norcocaine and N-hydroxynorcocaine was assessed in two inbred mouse strains; one that is relatively sensitive to cocaine hepatotoxicity but shows little enhancement in toxicity when pretreated with phenobarbital (DBA/2lbg), and one that shows little hepatotoxicity unless pretreated with phenobarbital (C57BL/6lbg). Although no significant differences between the strains were seen in the pharmacokinetics of cocaine, the half-life of both norcocaine and N-hydroxynorcocaine was significantly longer in DBA mice. Accordingly, the area under the curve values for hepatic norcocaine and N-hydroxynorcocaine were approximately 5- and 3-fold greater, respectively, in DBA as compared with C57BL mice. The higher levels of both norcocaine and N-hydroxynorcocaine in the DBA mouse are consistent with previously established differences in cocaine hepatotoxicity in these strains of mice. Pretreatment of C57BL mice with phenobarbital prolonged the half-life of norcocaine and N-hydroxynorcocaine 5- to 8-fold over C57BL control values.(ABSTRACT TRUNCATED AT 250 WORDS)


Metabolism and disposition of gemcitabine, and oncolytic deoxycytidine analog, in mice, rats, and dogs. Gemcitabine, 2'-deoxy-2',2'-difluorocytidine, is a broad spectrum oncolytic compound with antitumor activity in solid tumor models. The pharmacokinetics, metabolism, and disposition of gemcitabine was examined in mice, rats, and dogs. All three species metabolize gemcitabine by deamination to the uracil metabolite. However, deamination in the mouse and dog was more extensive than in the rat. The mouse deaminated gemcitabine rapidly with the plasma concentration maximum of the uracil metabolite of gemcitabine being attained at 15 min postdosing compared with approximately 3 and 6 hr in the dog and rat, respectively. The rapid deamination in the mouse was also reflected in the plasma half-life of the parent compound. The mouse exhibited the shortest plasma half-life, approximately 0.28 hr, contrasted with 2.14 and 1.38 hr half-lives in rat and dog, respectively. Plasma AUC for the uracil metabolite of gemcitabine was 73%, 10.5%, and 315% of that for gemcitabine in the mouse, rat, and dog, respectively. Tissue concentrations of gemcitabine-derived radioactivity in the rat and mouse indicated that gemcitabine was rapidly distributed throughout the body. Half-lives of radioactivity in tissues of both the rat and mouse were relatively short, with the longest tissue half-lives of 5.7 and 3.0 hr, respectively. Plasma protein binding is negligible in all three species. The major route of elimination is via the urine in all three species with 76-86% of the dose excreted in the first 24 hr. The predominant radiolabeled component isolated from urine was gemcitabine in the rat and its uracil metabolite in the mouse and dog.


Specific and enantioselective sulfoxidation of an aryl-trifluoromethyl sulfide by rat liver cytochromes P-450. Evidence based on thermal stability and enzyme inhibition data suggests that the sulfoxidation of the drug toltrazuril by rat liver microsomes is catalyzed by different cytochromes P-450. Pretreatment of rats by different inducers--phenobarbital, 3-methylcholanthrene, dexamethasone, and triacetyloleandomycin--results in a 2.1-, 2.6-, 2.9-, and 1.8-fold increase, respectively, in the rate of sulfoxidation. The highest increase (8.4-fold) was observed after treatment of microsomes from triacetyloleandomycin-treated animals by potassium ferricyanide. Castration and aging also modify the sulfoxidase activity. The relative rate of formation of the two toltrazuril enantiomers [(A)- and (B)-sulfoxides] depends on the source of the microsomes, suggesting that different cytochromes P-450 have different stereoselectivities.


Role of guinea pig and rabbit hepatic aldehyde oxidase in oxidative in vitro metabolism of cinchona antimalarials. Cinchona alkaloids (quinine, quinidine, cinchonine, and cinchonidine) were incubated with partially purified aldehyde oxidase from rabbit or guinea pig liver. Reversed-phase HPLC methods were developed to separate the oxidation products from the parent drugs, and the metabolites were identified on the basis of their infrared and mass spectral characteristics. All four alkaloids were oxidized at carbon 2 of the quinoline ring to give the corresponding lactams. In addition, the dihydro contaminants of the cinchona alkaloids were also metabolized by aldehyde oxidase to the 2-quinolone derivatives. Kinetic constants for the oxidation reactions were determined spectrophotometrically and showed that these substrates have a low affinity (KM values of around 10(-5) M) for hepatic aldehyde oxidase, coupled with a relatively low oxidation rate. However, the overall efficiency of the enzyme (Vmax/KM) toward this group of compounds indicates that in vivo biotransformation by aldehyde oxidase will be a significant pathway. Microsomal metabolites were also isolated from quinine and quinidine incubations with rabbit or guinea pig liver fractions. 3-Hydroxyquinine (quinidine) and O-desmethylquinine (quinidine) were identified in microsomal and 10,000g supernatant extracts from quinine and quinidine, respectively. Oxidation of quinine via aldehyde oxidase appeared to be the predominant pathway in rabbit 10,000g fractions, because 2'-quininone was the major metabolite under these conditions with lower concentrations of the microsomal metabolites produced along with a dioxygenated derivative thought to be 3-hydroxy-2'-quininone.


Microbial models of mammalian metabolism. N-dealkylation of furosemide to yield the mammalian metabolite CSA using Cunninghamella elegans. Furosemide (Lasix), a widely used diuretic, is metabolized by the fungus Cunninghamella elegans (ATCC 36112) to 4-chloro-5-sulfamoyl anthranilic acid (CSA), a metabolite also present in mammalian systems. This metabolite was isolated following preparative-scale incubations of C. elegans, and was characterized by comparison with standard CSA using 13C-NMR, mass spectrometry (high-resolution mass spectra, electron impact mass spectra), UV, TLC, and HPLC with fluorescence detection. Because a known complication with furosemide studies is the spontaneous formation of CSA by decomposition of furosemide during incubation, extraction, and/or analysis, a time course study was conducted to determine the rate of CSA formation caused by metabolism vs. the relatively low rate of CSA formation caused by spontaneous decomposition.


Substrates for microsomal azoreductase. Hammett substituent effects, NMR studies, and response to inhibitors. In previous studies on azoreduction by microsomal cytochrome P-450, we identified two classes of substrates structurally related to 4-dimethylaminoazobenzene. Both require polar electron-donating groups for binding to enzyme and are differentiated by their structure, their redox potentials, their rates of chemical and enzymic reduction, and the influence on their metabolism of inducing agents, CO and O2. Azo compounds whose reductions are insensitive to CO and O2 (I-substrates) contain electron-donating substituents on either ring. Azo compounds whose reductions are O2- and CO-sensitive (S-substrates) also contain electron-withdrawing groups on the opposite (prime) ring. For all dyes, NMR studies revealed minor differences in the chemical shifts of the protons attached to the phenyl ring substituted with electron-donating substituents (ring A). This is consistent with the narrow range of pKa's (basicity) and KM values for all substrates. However, there are significant differences in the chemical shifts of the aromatic protons of the prime ring (ring B). The difference in chemical shifts is most pronounced for aromatic protons adjacent to the prime ring substituents, showing a clear distinction between I and S substrates. Furthermore, the Hammett sigma substituent constants on the prime ring clearly distinguish between the two classes of dyes. I- and S-substrates have negative and positive sigma Hammett values, respectively. This implies that the mechanism of microsomal azoreduction is critically dependent on the charge and redox potentials of the dyes and is exclusively determined by the nature of the substituents on the prime ring.(ABSTRACT TRUNCATED AT 250 WORDS)


Pharmacokinetics of D(+)-usnic acid in rabbits after intravenous and oral administration. The pharmacokinetics of D(+)-usnic acid--a lichen antitubercular, antitumor, and enzyme-inhibiting agent--was studied in rabbits following intravenous or oral administration of 5 and 20 mg/kg body weight doses, respectively. Plasma samples were collected at different time intervals, and usnic acid was determined by HPLC. Plasma usnic acid levels following intravenous administration showed a triexponential elimination with a mean +/- SD terminal half-life of 10.7 +/- 4.6 hr. The volume of distribution of the central compartment and systemic clearance were 43.9 +/- 21.3 ml/kg and 12.2 +/- 3.0 ml/hr/kg, respectively. Pharmacokinetic parameters obtained, based on compartmental and noncompartmental approaches, were comparable. Plasma concentration data obtained after oral administration were analyzed using a noncompartmental method. Peak plasma level (Cmax) of 32.5 +/- 6.8 micrograms/ml was achieved in 12.2 +/- 3.8 hr (tmax). Mean absolute bioavailability of usnic acid following oral administration was 77.8%.


Disposition and metabolism of triprolidine in mice. The disposition of the antihistamine, triprolidine, was studied in male and female CD-1 mice after a single oral 50 mg/kg dose of [14C]triprolidine HCl. Urine and feces collected over 72 hr postdosing were analyzed for total radiocarbon, and for parent drug and metabolites by radiochromatography. Structures of metabolites were determined by GC/MS, direct probe MS, FAB/MS, LC/MS, NMR, and IR techniques. More than 80% of the dose was recovered in the urine, with the remainder recovered in the feces. The carboxylic acid analog of triprolidine (219C69) was found to be the major metabolite in urine and feces, accounting for an average of 57.6% of the administered dose. Three minor metabolites were identified as a gamma-aminobutyric acid analog of triprolidine, a pyrrolidinone analog of 219C69, and a pyridine-ring hydroxylated derivative of triprolidine. Parent drug could only be detected in urine and accounted for 0.3% (females) to 1.1% (males) of the dose. The results of this study showed that triprolidine was absorbed well but extensively metabolized when administered orally to mice.


Studies on tertiary amine UDP-glucuronosyltransferases from human and rabbit hepatic microsomes. The conversion of tertiary amines to quaternary ammonium glucuronides was investigated in human liver microsomes, and characteristics of the UDP-glucuronosyltransferase (UGT) catalyzing quaternary ammonium glucuronidation were evaluated. In addition, a rabbit liver microsomal UGT mediating this reaction was studied. The kinetics of quaternary ammonium glucuronidation of cyproheptadine, tripelennamine, amitriptyline, and doxepin in intact human liver microsomes was determined. Tripelennamine was found to have the lowest apparent KM and was used as a representative substrate for further studies. A polyclonal antibody preparation raised in sheep against rabbit liver p-nitrophenol UGT was found to inhibit tripelennamine glucuronidation in solubilized human liver microsomes, but had no effect on p-nitrophenol, 4-methylumbelliferone, 4-aminobiphenyl, estriol, morphine, or naloxone glucuronidation. This antibody also inhibited tripelennamine glucuronidation in solubilized rabbit liver microsomes, but had little or no effect on estrone, testosterone, estradiol, androsterone, and morphine glucuronidation. Chlorpromazine competitively inhibited tripelennamine glucuronidation. This inhibition was markedly enhanced by UV light irradiation. [3H] Chlorpromazine binding to solubilized human liver microsomes was also increased by UV light. The binding was antagonized by substrates for tertiary amine UGT but not by substrates for morphine UGT. These studies suggest that the tertiary amine UGT is photo-affinity-labeled by chlorpromazine. Furthermore, it would appear from immunoinhibition and [3H]chlorpromazine labeling experiments that tertiary ammonium glucuronidation is catalyzed by a unique and distinct UGT in rabbit and human liver microsomes.


Disposition of triprolidine in the male beagle dog. Three male beagle dogs were given 2.5 mg/kg doses of [14C]triprolidine HCl monohydrate (2.09 mg/kg of the free base) by intravenous and oral routes, in a nonrandomized cross-over experiment. After either route of administration, approximately 75% of the dose was excreted in the urine, and the remainder was excreted in the feces. Triprolidine was extensively metabolized, with less than 1% of the parent drug recovered in the excreta after either route of administration. Three metabolites were isolated from excreta and identified, including the major metabolite (metabolite 1, 219C69), in which the toluene ring methyl group was oxidized to a carboxylic acid, a metabolite (metabolite 2) in which the pyrrolidine ring was opened with oxidation of the terminal carbon to a carboxylic acid (a gamma-aminobutyric acid), and a metabolite (metabolite 3) that was a pyrrolidinone derivative of 219C69. Other metabolites in urine and feces were present in amounts too small for quantitation or identification. Route of administration had little effect on the metabolic pattern of triprolidine. Thus, after oral administration of triprolidine, a mean of 49.1% of the dose was excreted as 219C69, 12.0% as metabolite 2, 3.4% as metabolite 3, and 0.6% as triprolidine, while after intravenous administration, a mean of 50.8% of the dose was excreted as 219C69, 11.1% as metabolite 2, 4.2% as metabolite 3, and 0.8% as triprolidine. Plasma contained triprolidine, 219C69, and metabolite 2, as well as other apparent metabolites that were present at levels too low for quantitation. Mean pharmacokinetic parameters calculated for triprolidine after intravenous dosing were: CL = 24.4 ml/min/kg, Vdss = 5.8 liters/kg, and Vc = 1.6 liters/kg.(ABSTRACT TRUNCATED AT 250 WORDS)


Oxidation of carbovir, a carbocyclic nucleoside, by rat liver cytosolic enzymes. Enantioselectivity and enantiomeric inhibition. Previous metabolism studies of (-)-cis-carbovir (1'R-cis-2-amino-1,9-dihydro-9-[4'S-hydroxymethyl-2-cyclopenten-1- yl]-6H- purin-6-one), an antiviral agent, have shown that the major route of metabolism of carbovir in the rat is oxidation of the methylene hydroxyl group of the cyclopentadiene ring to form the corresponding 4'-carboxylic acid metabolite. We have determined that rat hepatic alcohol dehydrogenase and aldehyde dehydrogenase are responsible for this biotransformation through sequential oxidation of the alcohol through the aldehyde to the carboxylic acid. The results of incubations of racemic (+/-)-cis-carbovir with rat liver cytosol showed that this oxidation occurs enantioselectively favoring the (+)-enantiomer by a factor of 6- to 7-fold. We have proven that alcohol dehydrogenase contributes to the enantioselectivity of the overall oxidation process, but were unable to determine whether or not any contribution is made by aldehyde dehydrogenase. Parallel incubations conducted with the separate enantiomers revealed that the concentration required to achieve a half-maximal rate for the oxidation of the (+)-enantiomer (0.27 mM) was one-fifth that required for the (-)-enantiomer (1.36 mM). Results from enantiomeric inhibition studies showed that (+)-carbovir inhibited the oxidation of (-)-carbovir. In contrast, (-)-carbovir did not inhibit the oxidation of (+)-carbovir.


Clinical pharmacology of combined oral uracil and ftorafur. Phase I clinical trials of the combination of oral uracil with ftorafur (Ft) were conducted in patients with solid tumors over either a 5-day (345 mg/m2/day) or a 28-day (160 mg/m2/day) period. The uracil dose, which was four times the Ft dose (molar basis), was previously shown to be optimal at inhibiting the degradation of 5-fluorouracil (5-FU). Pharmacology was performed on the first dose of the first day of therapy. Ft was measured by HPLC, whereas uracil and 5-FU were measured using GC/MS. Plasma levels were highest for Ft, followed by uracil and 5-FU at all time points. Peak and trough levels after selected subsequent doses were also measured; these varied in the individual from day to day. Maximum plasma levels (Cpmax) for Ft, uracil, and 5-FU except in one patient were achieved at 0.6-2.1 hr, 0.6-4.1 hr, and 0.7-2.0 hr, respectively. Generally, lower doses yielded more rapid decay of 5-FU and uracil levels than did higher doses. No correlation was observed between myelotoxicities (granulocytopenia and leukopenia) and the Cpmax and AUC0-6hr of Ft (p > 0.2). However, after the highest uracil and Ft dose (approximately 300 mg/m2/Ft study dose), the Cpmax and AUC0-6hr values of 5-FU revealed significant differences (p < 0.05) in three patients each with and without myelotoxicity. These associations were similarly observed with uracil. Our findings thus indicate that measuring plasma uracil and more importantly, the 5-FU levels, may predict hematological toxicity and enable subsequent dose adjustments.


Investigation of conjugated metabolites of 4-hydroxyandrost-4-ene-3,17-dione in patient urine by liquid chromatography-atmospheric pressure ionization mass spectrometry. Metabolism of the anticancer drug 4-hydroxyandrost-4-ene,3,17-dione (4OHA) was studied in cancer patients by HPLC-MS-MS. 40HA was administered orally to a breast cancer patient. The drug was extensively metabolized and was excreted in the urine as the 4OHA-glucuronide, 3 alpha-hydroxy-5 beta-androstan-4,17-dione (3 alpha OHA)-sulfate (or 4-hydroxytestosterone-sulfate) and 3 alpha,17-dihydroxy-5 beta-androstan-4-one (3,17-OHA)-sulfate conjugates in the 4 hr posttreatment sample. Other metabolites include 4OHA-sulfate, 3 alpha OHA-glucuronide, and 3,17-OHA-monoglucuronide. When 4OHA was given to the prostatic cancer patients intramuscularly, different metabolites were observed as compared with the female studies. The most noticeable difference is the absence of 4OHA-sulfate in both 24 and 48 hr posttreatment urine samples. The drug was eliminated mainly as 4OHA-glucuronide, 3 alpha OHA-sulfate, and 3,17-OHA-monosulfate. Other metabolites that have been detected include 3 alpha OHA-glucuronide, 3,17-OHA-glucuronide, 3,17-OHA-disulfate, and an unknown metabolite. The variation observed in metabolism could be attributed to a different route of drug administration (oral and intramuscular) and sex difference among the patients. This study describes the utilization of HPLC-MS-MS for monitoring the 4OHA conjugates and provides the first evidence of the presence of 4OHA-sulfate and its analogs in patient urinary extracts.


Oxidation of aldose reductase inhibitors ALO-4114 and ALO-3152 catalyzed by liver microsomes. Rat and Cynomolgus monkey liver microsomes catalyze the oxidation of 2.7-difluoro-4.5-dimethoxyspiro (9H-fluorene-9,4'-imidazolidine)-2',5'-dione (ALO-4114) to its monomethoxymetabolite (ALO-4417). Formation of this product by O-demethylation of ALO-4114 is catalyzed by NADPH and oxygen-dependent microsomal enzymes with the properties of P-450 monooxygenases. The reaction is blocked by inhibitors selective for these enzymes and activity increases about 2-fold in rats pretreated with phenobarbital or methylcholanthrene. The increase in the O-demethylation of ALO-4114 was, however, considerably less than the increase in benzphetamine N-demethylation or nitrophenetole O-deethylation activities in liver microsomes from rats pretreated with either phenobarbital or methylcholanthrene. Rats pretreated with 20 or 40 mg/kg of ALO-4114 for 3-4 days failed to change significantly the rate of ALO-4114 O-demethylase activity of liver microsomes. O-Demethylation of the achiral ALO-4114 yields the chiral ALO-4417. The enantiomers separated on a Daicel Chiracel AS column by HPLC indicated that O-demethylation of ALO-4114 by microsomes from untreated rats was only slightly stereoselective. However, rats pretreated with methylcholanthrene not only enhanced activity, but also increased the formation of one enantiomer. Further oxidative metabolism of the enantiomers was slow and barely detectable in vitro. Studies conducted with Cynomolgus monkey liver microsomes from one male and one female per experimental group were generally consistent with those from the rat, but some differences were noted. Whether the differences are real or only reflect individual variations caused by the small sample size is not known at present.


The systemic availability of oral glutathione. When the plasma glutathione concentration is low, such as in patients with HIV infection, alcoholics, and patients with cirrhosis, increasing the availability of circulating glutathione by oral administration might be of therapeutic benefit. To assess the feasibility of supplementing oral glutathione we have determined the systemic availability of glutathione in 7 healthy volunteers. The basal concentrations of glutathione, cysteine, and glutamate in plasma were 6.2, 8.3, and 54 mumol.l-1 respectively. During the 270 min after the administration of glutathione in a dose of 0.15 mmol.kg-1 the concentrations of glutathione, cysteine, and glutamate in plasma did not increase significantly, suggesting that the systemic availability of glutathione is negligible in man. Because of hydrolysis of glutathione by intestinal and hepatic gamma-glutamyltransferase, dietary glutathione is not a major determinant of circulating glutathione, and it is not possible to increase circulating glutathione to a clinically beneficial extent by the oral administration of a single dose of 3 g of glutathione.


Long-term hemopoietic repopulation by Thy-1lo, Lin-, Ly6A/E+ cells. Murine bone marrow Thy-1lo, Lin-, Ly6A/E+ cells have been isolated by fluorescence-activated cell sorting (FACS). This population contained up to 27% in vitro colony-forming cells (CFC) when stimulated by interleukin 3 (IL-3) and 5% day-12 spleen colony-forming units (CFU-S) (uncorrected for seeding efficiency). As few as 100 cells were able to reconstitute the myeloid and lymphoid compartments of lethally irradiated recipients for periods of up to 72 weeks. Over the range of 30-560 transplanted cells, three patterns of engraftment were observed; the proportion of donor cells increased gradually to values of > 90%, gradually declined, or remained static over the 72-week observation period. When the donor cell percentage in the peripheral blood exceeded 60%, both myeloid (neutrophils and monocytes) and lymphoid (T- and B-lymphocytes) cells were of donor origin. Primary animals containing > 60% donor cells in their peripheral blood were able to engraft secondary recipients with donor cells of both myeloid and lymphoid lineages. Primary animals with < 20% donor cells in their peripheral blood contained bone marrow cells that were only able to produce lymphoid cells in the peripheral blood of secondary recipients. With > 90% of animals, including both primary and secondary recipients, there were no large fluctuations in the proportion of donor myeloid or lymphoid cells in the peripheral blood. Where changes occurred, with three exceptions, these were gradual. These data suggest that the Thy-1lo, Lin-, Ly6A/E+ population is heterogeneous and contains in vitro CFC, day-12 CFU-S, and long-term repopulating cells for both the myeloid and lymphoid lineages and cells capable of long-term repopulation of only the lymphoid lineage.


Cerebral protection by AMPA- and NMDA-receptor antagonists administered after severe insulin-induced hypoglycemia. Excitatory amino acids are implicated in the development of neuronal cell damage following periods of reversible cerebral ischemia or insulin-induced hypoglycemic coma. To explore the importance of glutamate receptor activation in the posthypoglycemic phase, we exposed rats to 20 min of insulin-induced severe hypoglycemia. The rats were treated immediately after the hypoglycemic insult with four regimes of glutamate receptor antagonists: (1) the AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propriate)-receptor antagonist NBQX [2.3-dihydroxy-6-nitro-7-sulfamoyl-benzo (F) quinoxaline] given as a bolus dose of 30 mg.kg-1 i.p., followed by an i.v. infusion of 225 micrograms.kg-1.min-1 for 6 h; (2) the non-competitive NMDA-receptor antagonist, dizocilpine (MK-801) 1 mg.kg-1 given i.v.; (3) a combined NBQX treatment, (a bolus dose of 10 mg.kg-1 i.p., followed by an i.v. infusion of 225 micrograms.kg-1.min-1 for 6 h), with dizocilpine 0.33 mg.kg-1 given twice i.p. at 0 and 15 min after recovery and (4) the competitive NMDA-receptor blocker CGP 40,116 [D-(E)-2-amino-4-methyl-5-phosphono-3- pentenoic acid] 10 mg.kg-1 given i.p. In the striatum, all glutamate receptor blockers significantly decreased neuronal damage by approximately 30%. An approximately 50% decrease in neuronal damage was demonstrated in neocortex and hippocampus following the combined treatment with NBQX and dizocilpine, while protection was variable following the treatment with a single glutamate-receptor antagonist.(ABSTRACT TRUNCATED AT 250 WORDS)


An analysis of adrenergic influences on the sural-gastrocnemius reflex of the decerebrated rabbit. The sural-gastrocnemius reflex was observed in decerebrated rabbits during intrathecal application of four alpha-adrenoceptor antagonists. Idazoxan and yohimbine, which are antagonists at the alpha 2-receptor, caused facilitation of the reflex, although idazoxan was more potent and produced a larger overall increase in the reflex response. However, when given after yohimbine, idazoxan elicited no further increase in reflex responses. The differences between the two drugs may result from the interaction of yohimbine with receptors for 5-hydroxytryptamine. The selective alpha 1-receptor antagonist prazosin had no consistent effects when given alone, but reduced the facilitatory effects of idazoxan. The putative selective post-junctional alpha 2-receptor blocker SK&F 104078 had no significant effects when given alone, nor did it influence the facilitatory action of a subsequent dose of idazoxan. Section of the spinal cord in the presence of idazoxan always caused a decrease in gastrocnemius responses to sural nerve stimulation. These data show that the facilitatory effects of idazoxan are almost certainly mediated at the spinal cord and that they do not involve blockade of alpha 1-receptors. It appears that idazoxan acts by blockade of adrenergic descending inhibition in combination with increased descending facilitation. The inhibition is probably mediated through noradrenaline acting at alpha 2-receptors, and the facilitation may be the result of release of noradrenaline (acting at alpha 1-receptors) and 5-hydroxytryptamine in the spinal cord.


[Villous tumors of the Wirsung's duct and pancreatic intraductal adenocarcinoma: interrelation or accidental association?]. Villous neoplasms of the main pancreatic duct are uncommon. Two cases of neoplasm of the main cephalic pancreatic duct in 61- and 42-year-old patients presenting with long standing (10 and 12 years) history of abdominal pain are reported. In both cases, duodenal fistula was present and mucus was observed by endoscopy at the fistula and major papilla levels. Endoscopic retrograde pancreatography showed a stricture of the main pancreatic duct in the pancreatic head. In one case, with incomplete stricture, pancreatic ducts disclosed typical features of chronic obstructive pancreatitis and contained mucus casts. Histologic examination of total and proximal duodenopancreatectomy showed a villous neoplastic pattern with focal malignant changes within the main pancreatic duct. The adjacent pancreatic tissue showed signs of stromal invasion without lymph node or nervous infiltration. Glandular parenchyma was atrophic in the pancreatic body and tail, with extensive fibrosis, and the pancreatic duct depicted signs of nonpapillary hyperplasia. Histochemical study disclosed a predominant sialomucin secretion by villous adenoma and sulfomucin secretion by epithelial cells lining the accessory or main caudal pancreatic ducts. These results lead us to suggest a possible relationship between villous adenoma of ducts and pancreatic adenocarcinoma.


DNA profiling in a genetically isolated population using three hypervariable DNA markers. We determined the allele frequencies for three hypervariable DNA loci D2S44, D1S7 and D7S21 using the probes YNH24, MS1 and MS31 in the genetically isolated Finnish population. The allelic length ranges were 1.7- < 6.0 kb for YNH24, 1.7- < 18.0 kb for MS1 and 3.2- < 12.0 kb for MS31. High heterozygosity rates (0.94-0.96) were detected for all three probes. In 48 mother-child pairs no mutations were found using the probes YNH24 and MS31, whereas a mutation rate of 0.064 was observed for probe MS1. In addition, an unexpected four-band pattern was detected in 1 out of 170 individuals using the probe MS1, suggesting complex DNA polymorphism based on both a variable number of tandem repeats and restriction site polymorphism. Our findings also show that all three probes are valuable in individual identification in this genetically isolated population.