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71.
EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4+<300 cells/mm3, p <  .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm3) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis.  相似文献   
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73.
Purpose. Humans and guinea pigs metabolise morphine extensively, forming the isomers morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in relatively similar ratios. Both metabolites are formed in the liver, and their greater polarity relative to the parent aglycone may limit their permeability across hepatic membranes. This study compared the disposition of hepatically-generated M3G and M6G in perfused livers isolated from guinea pigs. Methods. Livers were perfused at 30 ml/min in a non-recirculating manner with Krebs bicarbonate buffer containing morphine (6 to 7 M). Perfusing medium, venous perfusate and bile were collected at regular intervals and concentrations of morphine, M3G and M6G determined by reversed-phase HPLC. Results. Concentrations of morphine, M3G and M6G in perfusate and the rates of biliary excretion of M3G and M6G were consistent between 20 and 50 min of perfusion. The mean (±s.d.) ratio for the rate of formation of M3G relative to M6G was 3.7 ± 1.5. A mean 33 ± 3% of morphine extracted by the liver was recovered as summed M3G and M6G. Of the M3G and M6G formed during a single passage, 19 ± 11% and 9 ± 9%, respectively, was excreted into bile; the values were significantly different (P = 0.002). Conclusions. A greater fraction of hepatically-generated M3G excreted into bile compared to that for M6G reflects differences in their relative transport across sinusoidal and canalicular membranes of hepatocytes, possibly via carrier-mediated systems.  相似文献   
74.
The present study used stereological methods to determine whether long-term administration of lithium, with or without haloperidol, affects the number and average volume of neocortical neurons. Twenty-five rats were divided into three groups and given no treatment, lithium, or lithium combined with haloperidol. Serum lithium levels ranged from 0.5 to 0.8 mmol/l. Haloperidol was injected intraperitoneally at a daily dose of 1 mg/kg. After 30 weeks of treatment, the animals were killed and the brains were prepared. Neocortical volume, density of neurons, total number of neurons and mean volume of neurons were estimated. As no differences were found between the groups, the present study provides no evidence for quantitative morphological changes in the cerebral cortex due to long-term therapeutic levels of lithium, with or without haloperidol.  相似文献   
75.
Larsen JL  Burkman TW 《Endocrine》1995,3(3):221-226
The lactogen receptor has been suggested to associate with one or more G proteins despite the absence of a 7-transmembrane spanning sequence. These studies were designed to determine whether lactogens acutely increase GTP binding to or GTPase activity in Nb2 cell membrane. Incubation of Nb2 cell membrane with either ovine PRL (10 ng/ml) or diluent for 0–1 h resulted in a decrease in total35S-GTP binding to both with no difference in GTP binding between PRL- and diluent-treated membranes. There was also no change in35S-GTP binding to Nb2 cell membrane incubated with increasing oPRL concentrations (0.001–100 ng/ml) for 60 min. α-32P-GTP photoaffinity labelling was used to evaluate changes in GTP binding to specific G proteins. Photoaffinity labelling of α-32P-GTP to no G protein was changed after preincubation with oPRL (10 ng/ml) for 0–60 min or with oPRL (0.01–10 ng/ml) for 60 min. Finally, it was determined whether oPRL had any acute effect on GTPase activity, as determined by release of32Pi from γ-32P-GTP. When Nb2 cell membrane was preincubated for 0–60 min with oPRL (10 ng/ml) or a range of oPRL concentrations (0–10 ng/ml), no change in GTPase activity was observed. However, when Nb2 cells were incubated with lactogen for 0–7 h, GTPase activity in equal quantities of Nb2 cell membrane prepared from those cells increased over time. Increased GTPase activity (64.9–74.4%;P<0.03 compared to 0 h) was observed after 4–7 h incubation with lactogen. In summary, addition of lactogen to Nb2 cell membrane did not acutely increase either GTP binding or GTPase activity. Yet when Nb2 cells were incubated with lactogen for 4 h prior to preparation of membrane, GTPase activity was significantly increased. This evidence, in addition to our previous results showing that 4 h incubation with lactogen increased G protein β subunit concentration and pertussis toxin-stimulated ADP-ribosylation of Gi, support a role for delayed lactogen modulation of one or more G proteins in the Nb2 cell, requiring at least 4 h for maximal effect.  相似文献   
76.
OBJECTIVES: To confirm or refute the hypothesis that organic farmers have higher sperm concentrations than traditional farmers. METHODS: Traditional and organic farmers were selected randomly from central registers, and 171 traditional farmers and 85 organic farmers delivered one semen sample before the start of the spraying season. The participation rate was 28.8% among traditional farmers and 42.9% among organic farmers. RESULTS: The median sperm concentration for traditional and organic farmers was 58 million/ml and 64 million/ml, respectively. After adjustment for several confounders, sperm concentration, total count, proportion of non-vital spermatozoa, sperm chromatin structure, and motility variables did not differ significantly between the two groups. The traditional farmers had a significantly lower proportion of normal spermatozoa, but this result was not confirmed in a second sample. Organic farmers had slightly higher inhibin B concentration and testosterone/sex hormone binding globulin ratio. CONCLUSION: Despite slight differences in concentrations of reproductive hormones, no significant differences in conventional measures of semen quality were found between organic and traditional farmers.

 

  相似文献   
77.
The phenotypic expression of haemolysins and the presence of genes encoding alpha and beta-haemolysin were determined in 105 Staphylococcus aureus isolates from bovine mastitis, 100 isolates from the nostrils of healthy humans, and 60 isolates from septicaemia in humans. Furthermore, the possible change in expression of haemolysins after subcultivation in human and bovine blood and milk was studied in selected isolates. Alpha-haemolysin was expressed phenotypically in 39 (37%) of the bovine isolates, in 59 (59%) of the human carrier isolates, and in 40 (67%) of the isolates from septicaemia. Beta-haemolysin was expressed in 76 (72%) bovine, 11 (11%) carrier, and 8 (13%) septicaemia isolates. Significantly more bovine than human isolates expressed beta-haemolysin and significantly fewer expressed alpha-haemolysin. Genotypically, the gene encoding alpha-haemolysin was detected in all isolates. A significant difference in the prevalence of the gene encoding beta-haemolysin between the bovine (96%), human carrier (56%) and isolates from septicaemia (57%) was found. Of the bovine isolates, 75% of those carrying the gene encoding beta-haemolysin expressed beta-haemolysin phenotypically, whereas only 20% of the carrier isolates and 24% of the septicaemia isolates did so. No change in expression of haemolysins could be observed after subcultivation of bovine isolates in human blood and milk. After 5 to 10 subcultures in bovine blood and 1 to 4 in bovine milk, 9 of 10 human isolates originally phenotypically beta-haemolysin negative initiated the expression of beta-haemolysin. This study showed that a larger proportion of S. aureus of bovine origin carry the beta-haemolysin gene compared to isolates from humans. Furthermore, a larger number of the isolates of bovine origin carrying the beta-haemolysin gene express this gene phenotypically compared to isolates of human origin.  相似文献   
78.
A duplication artefact is sometimes encountered on ultrasound examination of the left kidney. It is caused by sound beam refraction between the spleen and adjacent fat. The purpose of this study was to analyse the frequency and types of such artefacts, and examine their physical background. The examiner searched for a left renal duplication artefact in 150 unselected abdominal ultrasound studies. A disturbed contour of the left kidney could be formed in 34 of 123 patients in whom the spleen was in the image without covering the kidney completely. An artefact was seen significantly more often when the lower pole of the spleen was rounded (30/87) than when it was wedge shaped (4/36) (p < 0.02). The artefacts could be categorized into complete upper pole duplication (n = 4), incomplete upper pole duplication (n = 14) and bayonet artefact (n = 16). The thickness of the renal cortex appeared reduced with upper pole duplication artefacts owing to a geometric image compression, which could also be seen in an in vitro experiment. Left renal duplication artefacts are not rare when the upper part of the kidney is examined by ultrasound through the spleen.  相似文献   
79.
80.
Objective: This study evaluated Repro-Dose morphine (RDM; Reliadol from Nycomed Pharma), a new once daily controlled-release morphine formulation, against twice daily MST Continus (MST) at steady state in patients with chronic opioid responsive pain. Methods: A randomized double-blind two-way crossover design was used to evaluate the efficacy and adverse effects of RDM once daily or MST twice daily, at the same total daily doses, in patients with chronic stable pain (dose range 20–120 mg per day). During the RDM limb of the study active drug was administered in the evening and placebo in the morning. Dextromoramide was provided as escape analgesia throughout the study. Following a 5-day screening period, during which stability of oral opioid dose was verified, patients underwent two 5-day treatment periods, (one MST, one RDM) in random sequence. Pain scores, escape analgesia requirements and side-effects were compared using data from days 3, 4 and 5 of each treatment period. Any events or medication changes occurring during the study period thought liable to influence analgesia were regarded as protocol violations. Overall assessment and period preference was assessed by direct questioning. RDM treatment was regarded as successful if the amount of escape medication required during the RDM period was equal to or less than that required during the MST period. Results: Forty-seven patients were included in the study, of whom 40 completed both periods [the intention to treat (ITT) population], 31 in strict accordance with the protocol [the per protocol (PP) population]. Results were similar for both populations. There was no significant difference in pain scores or incidence of adverse events occurring during the MST and RDM periods. For the ITT population, requirements for escape medication during the RDM period were less than, equal to or greater than those recorded during the MST period for 14, 15, and 11 patients, respectively. Twenty-nine of 40 patients (72.5%) were therefore RDM treatment successes (95% confidence interval 56.1–85.4%). The percentage of patients preferring RDM (45%) combined with those with no preference (32.5%) was significantly higher than those preferring MST (22.5%; P = 0.0003). Conclusions: Oral morphine administered as RDM once daily is at least as effective and well tolerated as MST twice daily, with over 70% of patients in this double-blind crossover study reporting that RDM was equal or superior to MST. Received: 6 April 1998 / Accepted in revised form: 23 January 1999  相似文献   
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