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81.
LEVIER DAVID G.; MCCAY J. ANN; STERN MALVIN L.; HARRIS LOUIS S.; PAGE DENNIS; BROWN RONNETTA D.; MUSGROVE DEBORAH L.; BUTTERWORTH LEON F.; WHITE KIMBER L. JR.; MUNSON ALBERT E. 《Toxicological sciences》1994,22(4):525-542
This study was undertaken to investigate a number of immuneparameters which may be compromised with exposure to morphinesulfate. Mice were implanted subcutaneously with 8-, 25-, or75-mg morphine sulfate pellets. Placebo pellets of identicalmakeup to the 75-mg morphine pellet (without morphine of course)were used as a control. Twenty-four hours after implantationof a 75-mg morphine pellet, blood levels reached a peak of 1610ng/ml. Corticosterone increased in parallel with morphine andreached a peak level of 966 ng/ml 24 hr after implantation.The dose response of morphine to increase corticosterone, however,was fiat. The weight of the lymphoid organs, spleen and thymus,and the liver were significantly reduced in the morphine-treatedgroups. Morphine treatment was associated with an increase inserum albumin, SGPT, BUN, and alkaline phosphatase indicativeof hepatic damage. In contrast to increased serum proteins,the C3 component of complement was reduced in a dose-dependentmanner. Leukocyte number in the peripheral blood was significantlyreduced, while erythro-cyte number and hematocrit were bothincreased. The number of B cells and T cells was decreased inmorphine-treated animals. However, the percentage of T cellsrelative to B cells was increased. The primary IgM antibodyresponse to the T-depen-dent antigen, sheep red blood cells,was decreased. Natural killer cell activity was reduced in responseto morphine, as was the phagocytic capacity of Kupffer cells.Host-resistance models of Listeria monocytogenes or Streptococcuspneumoniae showed an increased resistance following administrationof morphine. This increased host resistance, however, was notdue to an increase in antimicrobial action of sera obtainedfrom mice treated with morphine. The majority of morphine'seffects on the immune system exhibited a flat dose response,suggesting that these effects may be mediated secondarily throughcorticosterone. 相似文献
82.
GOLDEY ELLEN S.; O'CALLAGHAN JAMES P.; STANTON MARK E.; BARONE STAN JR.; CROFTON KEVIN M. 《Toxicological sciences》1994,23(3):447-464
Testing procedures for identification of potential developmentalneurotoxicants were evaluated using two prototypical developmentalneurotoxicants, methylazoxymethanol (MAM) and methylmercury(MeHg). Evaluation of offspring of LongEvans rats incorporatedassessments of developmental toxicity, neurochemistry, histology,and behavior, with most testing being completed near weaning.A number of endpoints in the testing strategy were sensitiveto the effects of prenatal exposure to MAM [30 mg/kg on GestationDay (GD) 15]: (1) MAM caused reduced neonatal body weights butdid not effect viability or postnatal survivorship; (2) measurementof total and regional brain weight and histological analysisshowed that a number of regions, the cortex and hippocampusin particular, were affected by MAM exposure; (3) an assay forglial fibrillary acidic protein (GFAP) showed that the concentrationof this protein was significantly increased in the cortex andhippocampus of treated offspring; (4) a T-maze delayed-alternationprocedure indicated that MAM-treated pups were slower in theacquisition phase of the task relative to control pups; (5)motor activity testing revealed hyperactivity in treated offspringthat persisted into adulthood; and (6) acoustic startle proceduresrevealed reduced startle amplitudes in preweanlings. Few endpointswere significantly affected by prenatal MeHg exposure (1, 2,or 4 mg/kg on GD 615). High fetal and neonatal mortalityand lower neonatal body weights were detected at the highestdose of MeHg. Although minimal effects of MeHg may reflect arelative insensitivity of the test species and/or the test methods,the combined results from both chemicals suggest that some proceduresnot currently required in the developmental neurotoxicity guidelinemay be useful in hazard identification, and further evaluationwith other chemicals, species, strains, and/or exposure paradigmsmay be warranted. 相似文献
83.
Absorption, Metabolism, and Excretion of N,N-Diethyl-m-toluamide Following Dermal Application to Human Volunteers 总被引:1,自引:0,他引:1
SELIM SAMI; HARTNAGEL RALPH E. JR.; OSIMITZ THOMAS G.; GABRIEL KARL L.; SCHOENIG GERALD P. 《Toxicological sciences》1995,25(1):95-100
The absorption, metabolism, and excretion of N,N-diethyl-m-toluamide(DEET) in male human volunteers following dermal applicationof |14C|DEET was studied. DEET was applied to two groups ofsix volunteers either as the undiluted technical grade materialor as a 15% solution in ethanol. The material was applied overa 4 x 6-cm area on the volar surface of the forearm and wasleft in contact with the skin for 8 hr, then rinsed off theskin. Application sites also were tape stripped at 1, 23, and45 hr after rinsing. Serial blood samples and all urine andfeces were collected for 5 days after application. Aliquotsof these materials were analyzed for total radioactivity inorder to define absorption and excretion patterns. Urine samplesalso were analyzed by HPLC to characterize the metabolic profileand/or to identify metabolites. Absorption of DEET as evidencedby plasma radioactivity occurred within 2 hr after dose application.Elimination of radioactivity from plasma was rapid and quantifiablelevels of radioactivity were observed in plasma for only 4 hrafter the end of the 8-hr exposure period. Urine was the principalroute of excretion of radioactivity and accounted for an averageof 5.61 and 8.33/ of the applied dose in the undiluted DEETand 15/ DEET in ethanol groups, respectively. Excretion of radioactivityin the feces was less than 0.08/ of the applied dose in bothgroups. DEET did not accumulate in the superficial layers ofthe skin as evidenced by low amounts of radioactivity in thetape strippings. The major fraction of the applied radioactivitywas recovered in the skin rinses. Absorbed DEET was completelymetabolized and six major metabolites were observed in urine.Two major urinary metabolites tenta tively were identified.Based upon the percentage of applied dose recovered in the excreta,dermal absorption of DEET ranged from 3 to 8% with a mean of5.6/ in the volunteers applied undiluted technical grade DEET.The corresponding values for the volunteers applied 15/ DEETin ethanol were 4 to 14/ and 8.4/, respectively. 相似文献
84.
Nader Gordjani Rainer Burghard Dirk Müller Helga Mathäi Gunther Mergehenn Jekabs U. Leititis Matthias Brandis 《Pediatric nephrology (Berlin, Germany)》1995,9(4):419-422
The potential tubulotoxicity of tobramycin and cefotaxim were assessed in neonates by measuring the urinary level of adenosine deaminase binding protein (ABP) and urinary 1-microglobulin and 2-microglobulin. In a prospective study, 33 neonates who received tobramycin and cefotaxim for suspected neonatal sepsis were compared with 48 untreated newborns during the first 10 days of life. The urinary concentrations of ABP and its excretion rates, corrected for body weight and body surface area, were significantly increased from the 1st day of treatment. Urinary 1-microglobulin and 2-microglobulin were not elevated under tobramycin and cefotaxim during the first 2 days of treatment. We conclude that ABP may be a sensitive marker for the detection of proximal renal tubular injury during tobramycin and cefotaxim treatments of neonates. The increase in urinary ABP which occurs before an elevation of urinary 1-microglobulin and 2-microglobulin may reflect earlier structural than functional alterations. However, since none of the treated infants had signs of electrolyte disorders or glomerular dysfunction, the clinical relevance of ABP measurement should be reevaluated. 相似文献
85.
ZHONG Xiaoyan Sepp Kaul Astrid Eichler Gunther Bastert Department of Obstetrics Gynecology Tongji Hospital Tongji Medical University Wuhan Laboratory of Oncology Department of Obstetrics Gynaecology Univ 《华中科技大学学报(医学英德文版)》1999,19(3):181-184
RT-PCRamplificationoftumor-asso-ciated(carcinoembryonicantigen)and(or)organ-specific(cytokeratin19)mRNAhasbeenusedmainlyforthedetectionofcircu-latingtumorcellsandmicrometastasesinsolidtumors[1].Originally,theproductofamplificationwasanalyzedbygelelec… 相似文献
86.
Somatization in frequent attenders of general practice 总被引:5,自引:0,他引:5
P. J. M. Portegijs F. G. van der Horst I. M. Proot H. F. Kraan N. C. H. F. Gunther J. A. Knottnerus 《Social psychiatry and psychiatric epidemiology》1996,31(1):29-37
The DSM-III-(R) definition of somatization disorder is too restrictive for use in general practice. A more comprehensive definition, the somatic symptom index (SSI) has shown good validity in open populations. However, a definition has to differentiate validlywithin a population of frequent attenders to be a useful diagnostic instrument in general practice. We studied a threshold of five complaints (nearly identical to the SSI) in 80 Dutch general practice patients. Patients were selected on age (20–44 years), history of back, neck or abdominal complaints, and on frequency of consultation—at least 12 consultations in the previous 3 years, corrected for consultations with compelling somatic reason for encounter. Prevalence of somatization in this group was 45%. Women had a 2 times higher risk of somatization. A relation with age was not found. Somatization was related to depressive complaints (relative risk 2.5) and probably also to anxiety. Somatizing patients consulted their general practitioner more often and had more health problems (especially psychic problems) than non-somatizers. These results support the validity of this definition. The distinction between our definition of somatization and somatization defined as a symptom of psychiatric (e.g. depressive or anxiety) disorder is emphasized. 相似文献
87.
Subchronic Effects of Dieldrin and Phenobarbital on Hepatic DNA Synthesis in Mice and Rats 总被引:2,自引:1,他引:1
KOLAJA KYLE L.; STEVENSON DONALD E.; JOHNSON JASON T.; WALBORG EARL F. JR.; KLAUNIG JAMES E. 《Toxicological sciences》1996,29(2):219-228
Dieldrin, an organochlorine pesticide, has been shown to behepatocarcinogenic in mice but not rats. Phenobarbital, in contrast,induces hepatic tumors in both mice and rats. Previous studieshave shown that acute dietary exposure of rats or mice to eitherdieldrin or phenobarbital produces several liver changes, includingcentrilobular hypertrophy, induction of hepatic cytochrome P450,and increased liver weight. The present study examined the subchroniceffect of dieldrin (0.1, 1.0, 3.0, 10.0 mg dieldrin/kg diet)and phenobarbital (10, 50, 100, 500 mg phenobarbital/kg diet)on the induction of hepatic DNA synthesis and hepatocyte lethalityin male B6C3F1 mice and male F344 rats. Eight-week-old animalswere treated as above and evaluated for hepatic DNA synthesisafter 7, 14, 21, 28, and 90 days of continual treatment to dieldrinor phenobarbital. Maximal induction of hepatic DNA synthesisin mice was seen at the 14-, 21-, and 28-day sampling times.In rats, no significant increase in hepatic DNA synthesis orhepatocyte lethality was observed at any dose of dieldrin investigated.Phenobarbital produced a significant increase in hepatic DNAsynthesis in both rat and mouse liver following 7 days of treatment.The induction of DNA synthesis in rat liver was transient, withthe labeling index returning to control levels by 14 days oftreatment. In contrast, mice treated with phenobarbital showeda significant increase in hepatic DNA synthesis throughout thetreatment. In both mice and rats, dieldrin and phenobarbitalinduced hepatic DNA synthesis selectively in the centrilobularregion of the hepatic lobule. The lack of an increase in serumenzymes indicative of hepatic damage and the absence of liverhistopathology in mice or rats fed dieldrin or phenobarbitalindicate that the induction of DNA synthesis was not mediatedby a cytolethal, compensatory hyperplastic response, suggestinga mitogenic mechanism. Therefore, the species-specific inductionof hepatic DNA synthesis by either dieldrin or phenobarbitalcorrelated with the previously observed species-specific inductionof hepatic cancer by these two compounds. 相似文献
88.
Michael Stöckle Stefan Wellek Walter Meyenburg Gunther E. Voges Ulla Fischer Ulrich Gertenbach joachim W. Thüroff Christoph Huber Rudolf Hohenfellner 《Urology》1996,48(6):868-875
Objectives
To analyze the effectiveness of adjuvant polychemotherapy after radical cystectomy for nonorgan-confined transitional cell bladder cancer (Stages pT3b, pT4a, and/or pN1 or pN2).Methods
Of 166 consecutive patients undergoing cystectomy at two institutions from 1987 to 1993, 80 received adjuvant polychemotherapy with methotrexate, vinblastine, and cisplatin plus doxorubicin (MVAC) or epirubicin (MVEC), whereas 86 had cystectomy only. The patients were evaluated for relapse-free survival and length of progression-free interval on the basis of follow-up data obtained in 1995 and 1996.Results
Kaplan-Meier analysis revealed a significantly higher progression-free rate for patients after adjuvant chemotherapy (P=0.0002, log-rank test). With and without adjuvant chemotherapy, prognosis declined in a stepwise manner, depending on the extent of lymph node involvement. Nevertheless, the superior prognosis of the chemotherapy group could be demonstrated at each lymph node stage. Of the 166 patients, 49 had initially entered a prospective trial comparing adjuvant with no adjuvant treatment. That study was discontinued in December 1990 after an interim analysis revealed a significant prognostic advantage in favor of the 26 patients randomized to receive chemotherapy compared with the 23 control patients. Current follow-up data continue to demonstrate a significant improvement in progression-free survival in favor of patients randomized to receive adjuvant chemotherapy (P=0.0040). The follow-up period of patients living free of disease ranges from 58 to 96 months.Conclusions
Adjuvant chemotherapy with MVAC/MVEC leads to significant prolongation of relapse-free survival and improvement of the definitive cure rate after radical cystectomy for locally advanced transitional cell carcinoma of the urinary bladder. 相似文献89.
90.
SLIKKER WILLIAM JR; PAULE MERLE G.; ALI SYED F.; ANDREW C. SCALLET; BAILEY JOHN R. 《Toxicological sciences》1991,17(2):321-334
Chronic Marijuana Smoke Exposure in the Rhesus Monkey I. PlasmaCannabinoid and Blood Carbxyhemoglobin Concentrations and ClinicalChemistry Parameters SLIKKER, W., JR., PAULE, M. G., ALI, S.F., SCALLET, A. C., AND BAILEY, J. R (1991). Fundam. Appl Toxicol17, 321334. This report is the first in a series abouta large multidisciplinary study designed to determine whetherchronic marijuana (MJ) smoke exposure results in residual behavioraland/or neuropathological alterations in the rhesus monkey. Priorto the initiation of a year of chronic MJ smoke exposure, 64periadolescent male rhesus monkeys were trained for 1 year toperform five operant behavioral tasks and then divided, accordingto their performance in these tasks, into four exposure groups(n=1516/group): (1) a high dose (HI) group, exposed 7days/week to the smoke of one standard MJ cigarette; (2) a lowd m (LO) group, exposed on weekend days only to the smoke ofa standard MJ cigarate; (3) an extracted MJ cigarette (EX) group,exposed 7 days/week to the smoke of one ethanol-extracted MJcigarette; and (4) a sham group (SH), exposed 7 days/week tosham exposure conditions. Daily exposures for 1 year were accomplishedusing a mask that covered the subjects' nose and mouth. Averagebody weights (initially 3.7?0.5 kg, mean?SD) and rates of weightgain (approximately 0.1 kg/month) were the same for all groupsthroughout the entire experiment. During the first week of expsure,plasma concentrations of -9-tetrahydrocannabinol and 11-nor-9-carboxy-THCin the HI group were 59?7 (mean?SE) and 5.5?1.5 ng/ml, respectively,45 min after MJ smoke administration and did not change significantlyat similar times after exposure throughout the remainder ofthe year. Whole blood carboxyhemoglobin levels increased toapproximately 13% 1 min after expsure to smoke in either theMJ or the EX groups. Comparison of blood chemistry and hematologyvalues before, during, and after exposure indicated no differencesfor most parameters. During exposure, lymphocytes, alkalinephosphatase and -glutamyl transferase were depressed in theHI group compared to in the SH group. During exposure, aspartateaminotransferase was elevatd for both the HI and EX groups,suggesting a general effect of smoke exposure. Because theseeffects were transient and remained within the range of reportednormal values, these data indicate that long-term, experimentalexperimental exposure to MJ smoke is feasible and does not compromisethe general health of the rhesus monkey. 相似文献