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1.
In progressive systemic scleroderma, a disease of protean manifestations, involvement of the gastrointestinal tract is noted infrequently in patients who are asymptomatic, and is rarely fatal. We report the case of a 65-year-old woman who was admitted for ascitis related to a non A, non B cirrhosis. The patient presented with bacterial peritonitis due to colonic perforation by fecal impaction associated with sclerodermic involvement. Pathologic study of the resected colon showed that the true muscularis was very atrophic and fibrotic, characteristic of scleroderma. To our knowledge, this cause of ascitic fluid infection has not been previously reported.  相似文献   
2.
In naive mice, the selective D1 agonist, SK&F 38393 (7.5-30 mg/kg s.c.), induced a significant rise of body temperature (0.5-1 degree C) which was antagonized by SCH 23390 (100 micrograms/kg s.c.) and by flupenthixol (0.4 mg/kg i.p.). In mice treated with reserpine (5 mg/kg s.c.) 18 h before testing, which on its own caused intense hypothermia (10-12 degrees C), SK&F 38393 (1.87-30 mg/kg s.c.) induced a dose-dependent and more marked rise of body temperature (5-7 degrees C). Similarly, SK&F 38393 (30 mg/kg s.c.) partially prevented reserpine-induced hypothermia. The central origin of the SK&F 38393 effects in reserpine-treated mice is indicated by the rise of body temperature induced by the i.c.v. administration of the drug (12.5-50 micrograms per mice). The SK&F 38393-induced rise of body temperature in acutely reserpinized mice was antagonized by SCH 23390 (50-200 micrograms/kg s.c.), clozapine (1.87-30 mg/kg i.p.) or chlorpromazine (2-32 mg/kg i.p.) but not by metoclopramide (25 or 100 mg/kg i.p.) or amisulpride (12.5 or 50 mg/kg). In naive mice, apomorphine (1 mg/kg s.c.) or LY 171555 (0.4 mg/kg s.c.) induced hypothermia which was antagonized by amisulpride (12.5 mg/kg i.p.); a transiently increased body temperature was even measured 30 min after apomorphine injection in amisulpride-treated mice. Apomorphine (1 mg/kg s.c.) induced a rise of body temperature in acutely reserpinized mice which was significantly reduced by SCH 23390 (50 and 200 micrograms/kg s.c.) and significantly increased by amisulpride (12.5 and 50 mg/kg i.p.). These data suggest that pharmacologically different dopamine receptor subtypes mediate different effects on body temperature in mice: D1 dopamine receptors mediate a rise of body temperature which is increased in hypothermic reserpinized animals and dopamine receptors of the D4 subtype mediate the decrease of body temperature in naive mice.  相似文献   
3.
The pathogenic mechanisms that lead to chronic hepatitis C are unknown. As hepatitis C virus (HCV) has been shown to induce T cell response, we assessed whether a particular T lymphocyte subset could be preferentially detected in the liver of patients with chronic hepatitis C in relation to viraemia or HCV genotypes. The immunophenotypes of liver-derived lymphocytes were analysed in 26 patients by flow cytometry and immunohistochemistry. Viraemia was quantified by branched DNA assay. Using this assay, HCV RNA was not detectable in six patients. HCV RNA was detected in 20 patients, and titres ranged from 8 to 137 x 10(6) Eq/ml. Genotyping was performed using a line probe assay. Type 1a, 1b, 2a, 3a and 4a were found to infect 2, 10, 2, 7 and 3 patients, respectively. The CD4+/CD8+ ratio of liver-derived lymphocytes was significantly higher (P < 0.01) in patients with detectable viraemia than in patients without detectable viraemia. In contrast, neither the percentage of gamma/delta T lymphocytes nor that of CD2+CD57+ cells was different in the groups. When comparing the CD4+/CD8+ ratio, the percentage of gamma/delta T lymphocytes or CD2+CD57+ cells according to genotype, the differences were not significant. These results suggest that the CD4+/CD8+ ratio of liver-derived lymphocytes is related to viraemia but not to HCV genotypes in patients with chronic hepatitis C, and that T lymphocytes may be involved in the pathogenesis of liver lesions in chronic hepatitis C.  相似文献   
4.
Prenatal trisomy 7 is usually a cell culture artifact in amniocytes with normal diploid karyotype at birth and normal fetal outcome. In the same way, true prenatal trisomy 7 mosaicism usually results in a normal child except when trisomic cells persist after birth or when trisomy rescue leads to maternal uniparental disomy, which is responsible for 5.5-7% of patients with Silver-Russell syndrome (SRS). We report here on the unusual association of SRS and Hirschsprung's disease (HSCR) in a patient with maternal uniparental heterodisomy 7 and trisomy 7 mosaicism in intestine and skin fibroblasts. HSCR may be fortuitous given its frequency, multifactorial inheritance and genetic heterogeneity. However, the presence of the trisomy 7 mosaicism in intestine as well as in skin fibroblasts suggests that SRS and HSCR might possibly be related. Such an association might result from either an increased dosage of a nonimprinted gene due to trisomy 7 mosaicism in skin fibroblasts (leading to SRS) and in intestine (leading to HSCR), or from an overexpression, through genomic imprinting, of maternally expressed imprinted allele(s) in skin fibroblasts and intestine or from a combination of trisomy 7 mosaicism and genomic imprinting. This report suggests that the SRS phenotype observed in maternal uniparental disomy 7 (mUPD(7)) patients might also result from an undetected low level of trisomy 7 mosaicism. In order to validate this hypothesis, we propose to perform a conventional and molecular cytogenetic analysis in different tissues every time mUPD7 is displayed.  相似文献   
5.
The aim of this study was to determine whether multicentre quality controls for the detectability of viral genomes could contribute to the improvement of diagnostic performance in the participating laboratories. The study was carried out during two successive rounds, during which 18 laboratories specialized in nucleic acid testing analyzed, through a polymerase chain reaction (PCR) assay, a common panel of GB virus C (GBV-C)/hepatitis G virus (HGV) RNA-positive and -negative samples. During the first round, the laboratories used either an 'in-house' PCR procedure or a partly standardized commercial test. After decoding the results of the first round, the procedures of the participating laboratories were compared in order to establish a consensus procedure deduced from those of the laboratories which provided the best results. During the second round, each participating laboratory could use the resulting consensus procedure, or its own procedure, or both. The results of this quality control study indicated that, whatever method used, even specialized and trained laboratories may give false-negative or false-positive results. The commercial assay did not guarantee a systematic high quality level of results. The striking heterogeneity of results observed among laboratories using the same commercial assay confirm that molecular biology methods need skilled technicians. The results of this quality control study suggest that full standardization of viral genome detection, including all steps of the procedure, is necessary and that the laboratories performing PCR should participate in repeated quality control studies, whatever technique is being used.  相似文献   
6.
Virological 1 examination of a severe infectious bronchitis (IB)-like field case in laying hens, led to the isolation of a coronavirus anti-genically different from Massachusetts, Connecticut and four Dutch IB variant strains. The virulence of the isolate for the fowl, and its dual tropism for the respiratory and genital tracts were demonstrated. In preliminary cross-protection studies Commercial vaccines did not protect against challenge with this isolate. These points and the possible economic significance of the virus are discussed.  相似文献   
7.
Cellular HIV-1 DNA level was sequentially measured by quantitative polymerase chain reaction in 141 patients not previously treated with highly active antiretroviral therapy (HAART), who were enrolled in a 72-week randomized trial (ANRS 081 "Trianon") comparing 2 regimens, including 3 drugs from 2 classes (indinavir + stavudine + lamivudine, group 1) or 3 classes (indinavir + stavudine + nevirapine, group 2). The median decrease from baseline to week 72 in cellular HIV-1 DNA level was not significantly different between the 2 groups (0.54 and 0.45 log10 copies/10 peripheral blood mononuclear cells [PBMCs] in groups 1 and 2, respectively), whereas a higher proportion of patients maintained a plasma HIV-1 RNA level less than 20 copies/mL at week 72 in group 1 than in group 2 (79% and 52%; P = 0.0009). Furthermore, the difference in cellular HIV-1 DNA decrease from baseline to week 72 between patients who achieved a plasma HIV-1 RNA level less than 20 copies/mL at week 72 and those who did not was not statistically significant (0.54 and 0.45 log10 copies/10 PBMCs, respectively; P = 0.14). The decay in cellular HIV-1 DNA from baseline to week 72 was higher in antiretroviral-naive patients than in pretreated patients (0.55 and 0.23 log10 copies/10 PBMCs, respectively; P = 0.0008). The cellular HIV-1 DNA level change under therapy was best fitted to a 2-phase decay model with a junction point at week 16, from which its half-life was estimated at 18 weeks during the initial phase and at 104 weeks thereafter. In conclusion, the changes under therapy in cellular HIV-1 DNA level, which were mostly coincident to those of plasma HIV-1 RNA, did not add significant information to the comparison of the viral efficacy of the 2 studied regimens.  相似文献   
8.
Summary Among four stereotyped manifestations that can be simultaneously quantified in mice treated with apomorphine (APO), two of them (climbing and sniffing) emerge at low APO dosages (below 1 mg/kg) whereas licking and sniffing require APO dosages above 6 mg/kg. However, in mice pretreated (either i.p. or i.c.v.) with sulpiride (especially the levo isomer) or (±)amisulpride in moderate dosage stereotyped licking and sniffing are elicited by APO in much lower dosage (0.75 mg/kg). As a consequence, in mice pretreated with these benzamide derivatives and receiving 0.75 mg/kg APO, a biphasic effect was observed: licking and gnawing progressively appear at low dosages, whereas they are progressively abolished at higher dosages.This potentiation of the effects of APO by (±)amisulpride is even more obvious (maximal scores increased) with larger test-doses of the dopamine agonist (up to 5 mg/kg). Amisulpride also allows the emergence of the two stereotyped behaviours in mice receiving other dopamine agonists in subthreshold dosages (Dipropyl 5,6-ADTN, dexamphetamine or cocaine). The potentation of APO is still observed after dopamine depletion by reserpine and -methylparatyrosine, whereas that of dexamphetamine is abolished. In contrast with the benzamide derivatives, haloperidol does not potentiate at any dosage the effect of APO but, at 0.15 mg/kg, suppresses licking and gnawing elicited by 0.75 mg/kg APO in mice pretreated with 6.25 mg/kg amisulpride or veralipride.Among a series of dopamine antagonists belonging to various chemical classes, only a number of discriminant benzamide derivatives (DBD), previously shown to differentially antagonise several APO-induced behavioural manifestations in rats (sulpiride, amisulpride, tiapride, sultopride, DO 701, LUR 2366 but not metoclopramide) potentiate APO (0.75 mg/kg) regarding licking and gnawing. In contrast, potentiation is not observed, even for a higher test dose of APO, with haloperidol, thioproperazine, pimozide, mezilamine, thioridazine or metoclopramide at any dosage tested.For the various DBD, the two stereotyped behaviours emerge at dosages at which climbing starts to be inhibited, suggesting that selective blockade of some inhibitory response to APO is responsible for the potentiation. Among other hypothesis the possibility that the peculiar behavioural properties of DBD is related to their differential recognition of two classes of dopaminergic binding sites is discussed.  相似文献   
9.
10.
The objective of this study was to further characterize the clinical and immunopathologic features of heavy chain deposition disease (HCDD), a recently described entity. Four patients were diagnosed as having HCDD on a kidney biopsy. All presented with nodular glomerulosclerosis with deposition of gamma1 heavy chains lacking CH1 epitopes, but without light chains. Two different patterns were observed in the serum. First, patients 1 and 2 had a circulating monoclonal IgGlambda containing a short gamma1 heavy chain lacking CH1 epitopes, with an apparent molecular weight of 40 kD consistent with a complete CH1 deletion. Biosynthetic experiments also showed that the deleted heavy chain was produced in excess compared with light chains, and was secreted in vitro together with half Ig molecules, although these abnormal components were not detected by Western blot analysis of whole serum. Second, patients 3 and 4 had a circulating monoclonal IgG1lambda with an apparently normal, nondeleted heavy chain subunit, but serum fractionation followed by immunoblotting revealed an isolated monoclonal gamma1 chain lacking CH1 epitopes. These data strongly suggest that renal deposition of a CH1-deleted heavy chain circulating in low amounts in the serum as a free unassembled subunit is a major feature of HCDD. The CH1 deletion is most likely responsible for the premature secretion in blood of the heavy chain by a clone of plasma cells.  相似文献   
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