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61.
Recent studies suggest that Epstein-Barr virus (EBV) can infect naïve B cells, driving them to differentiate into resting memory B cells via the germinal center reaction. This hypothesis has been inferred from parallels with the biology of normal B cells but has never been proven experimentally. Rag2−/− γc−/− mice that were transplanted with human CD34+ cord blood cells as newborns were recently shown to develop human B, T, and dendritic cells, constituting lymphoid organs in situ. Here we used this model to better define the strategy of EBV infection of human B cells in vivo and to compare this model system with different conditions of EBV infection in humans. Our results support the model of EBV persistence in vivo in cases that were characterized by follicular hyperplasia and a relatively normal CD4+ and CD8+ T-cell distribution. Intriguingly, in cases that were characterized by nodular and diffuse proliferation with a preponderance of CD8+ T cells, similar to infectious mononucleosis, EBV still infects naïve B cells but also induces clonal expansion and ongoing somatic mutations without germinal center reactions. Our results reveal different strategies of EBV infection in B cells that possibly result from variations in the host immune response. Future experiments might allow understanding of the mechanisms responsible for persistent EBV infection and provide targets for more highly tailored therapeutic interventions.  相似文献   
62.
Inhibitory effect of GABA on anaphylactic histamine releasein vitro is not mimicked by 2-aminoethansulphonic acid (taurine), an aminoacid unrelated to GABA neurotransmission.Tetrodotoxin (TTX) 6×10–7 M, a concentration known to block neuronal mechanism but not to modify muscle membrane and anaphylactic histamine release, strongly prevented the inhibition caused by GABA in the Schultz-Dale reaction and in anaphylactic histamine release.The inhibitory effect of GABA on anaphylactic reactionin vitro thus appears to be specific for this aminoacid and is neurogenic in nature, in that it requires integrity of neuronal mechanisms.  相似文献   
63.
Murine fibrosarcoma cells were examined for sensitivity to killing by natural killer (NK) and natural cytotoxic lymphocytes from mouse spleens. These tumor cell lines were sensitive to killing by effector cells which were nonadherent to plastic or nylon wool, Thy-1 negative, asialo-GM1 negative, and present in the spleens of beige mice, nude mice, and A/J mice, as well as in the spleens of normal syngeneic and allogeneic control mice. This indicates that the cytotoxic effects were due to natural cytotoxic lymphocytes rather than to NK lymphocytes, T-cells, or macrophages. Although the fibrosarcoma cells were not killed in vitro by endogenous NK cells, these tumor cells were able to "cold target" compete for Yac-1 (an NK-sensitive target) killing and to bind to asialo-GM1-positive, nonadherent spleen lymphocytes in a target cell binding assay. This suggests that the fibrosarcoma cells were recognized by NK cells. In addition, these cell lines were killed in a 4-h NK cytotoxicity assay by polyinosinic-polycytidylic acid-activated effector lymphocytes. The interaction between NK cells and the murine fibrosarcoma cells may have in vivo significance. When syngeneic mice were treated with anti-asialo-GM1 serum to eliminate NK activity and then given i.v. injections of the fibrosarcoma cells, many more lung tumors developed than in control animals. The structural basis for the recognition of the murine fibrosarcoma cells by the NK effector cells is not known. However, laminin may be involved. When the fibrosarcoma cells, which have receptors for the laminin molecule, were preincubated with laminin, they were reduced in their ability to compete for the killing of Yac-1 cells by the NK effectors and had reduced capacity to bind to NK cells in a target cell binding assay.  相似文献   
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Archives of Sexual Behavior - The Eunuch Archive (EA) is an online community which includes individuals who read and write sexual fantasies with themes related to castration and eunuchs. Here we...  相似文献   
66.
BackgroundPeyonie’s disease (PD) mostly affects males in the fifth decade of life, with a prevalence in the general population ranging between 0.5% and 20.3%. The pathology of PD is characterized by fibrosis of the tunic albuginea of the cavernous bodies of the penis, with the presence of pain in the erection and penile deformity. This is associated with decreased sexual function for both participants. The objective of the study was to investigate the influence of PD pathology on both male patients’ and their female partners’ sexual spheres, and analyze changes in sexual function and perception following penile correction surgery.MethodsProspective study, we included male patients with PD and their female partner sexually active. Patients underwent corporoplasty with multiple plications. The male and female sexuality was evaluated before surgery and three months after male treatment by the Female sexual Function Index (FSFI); International Index of Erectile Function (IIEF); Visual Analogical Scale (VAS).ResultsFrom January 2018 to November 2019 we included 35 couple. The female subjects before partner’s surgery presented dyspareunia, loss of sexual desire, inability to achieve orgasm, and sexual dissatisfaction. At three months after surgical treatment there was an improvement of sexual function in both male patients and female partners (desire P<0.0001, arousal P<0.0001, lubrification P<0.0001, orgasm P<0.0001, satisfaction P<0.0001, pain P<0.0001). As regarding male patients the pain decreased significantly (VAS score from 6 to 2.5), while there was no statistically significant improvement in erectile function (P=0.05).ConclusionsOur findings suggest that a viable approach to treatment of PD patients that involves their partners could lead to better functional and psychological results.  相似文献   
67.
Summary We investigated the role of urinary testosterone levels as a marker of risk of recurrent disease in 113 operable breast cancer patients (70 premenopausal, 43 postmenopausal). Twenty-four-hour urine collections for testosterone measurement were obtained before surgical treatment, between 20–40 days thereafter, and then every 6 months for 5 years. The cutoff values to separate high testosterone (A+) from normal testosterone (A–) were 8.0µg/24h in premenopause and 4.9µg/24h in postmenopause. Urinary testosterone levels were considered high when they exceeded the cutoff value in at least 2 of the first 3 measurements (pretreatment, post-treatment, 6 months) of each patient. According to the aforementioned criterion, 33 patients (29.2%) had high testosterone levels, which were associated to axillary node involvement in 16 patients. Thirteen of the latter relapsed during the 5-year follow-up period (5/7 in premenopause, 8/9 in postmenopause). Relapse-free survival (RFS) curves were drawn only for node-positive patients owning to the small number of recurrences observed in the node-negative group. In premenopausal node-positive patients, RFS was significantly different for patients presenting high and normal urinary testosterone levels (77% vs 28%, respectively; logrank test, p< 0.006). In postmenopausal node-positive patients, RFS was also different between the two groups (54% vs 11% in high and normal excretors, respectively) but the difference was not statistically significant. The present findings suggest that urinary testosterone is a prognostic indicator of early breast cancer recurrence in node-positive patients.  相似文献   
68.
The excitotoxins kainic acid and N-methyl d-aspartate (NMDA) were unilaterally injected in the rat striatum. Kainic acid injections resulted in a widespread pattern of Fos protein induction, mainly involving cortical olfactory structures and hippocampus. Immunoreactive cells were observed in large number 2–24 h after injection and had almost completely disappeared by 48 h. NMDA injections elicited a shorter (2–8 h) expression of Fos protein, involving a lower number of cells in cortical olfactory structures, a much larger number of cells in the other cortical regions, and not involving the hippocampus at all. Characteristically none of the two excitotoxins stimulated Fos expression from striatal neurons, even in the close vicinity of the needle tract. In addition to striatal lesions almost equivalent in size, the two excitotoxins caused distant lesions of different extension: kainic acid resulted in extensive neuronal degeneration in the olfactory-entorhinal cortices and among pyramidal neurons of the hippocampus; NMDA caused a less widespread neurodegeneration, restricted to the olfactory cortex. Administration of the competitive NMDA antagonist CGP 39551 largely prevented the distant, but not the local, neuropathological changes caused by intrastriatal kainic acid or NMDA. The expression of Fos protein, however, was partially prevented only in NMDA cases. The present results show a good relationship between the spreading of circuit overexcitation caused by the two excitotoxins and the regional and temporal patterns of Fos expression. The relationship between Fos expression and neuropathological condition remains, however, elusive.  相似文献   
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PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
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