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A unique factor, human T cell hypoglycaemic factor (hTCHF), has been shown to produce hypoglycaemia during the convalescent stage in the plasma of patients with Japanese encephalitis virus (JEV) infection. The present study was undertaken to investigate the ability of T cells from fresh peripheral blood mononuclear cells (PBMC) of such patients to produce hTCHF. The PBMC, as well as the individual subpopulations, were cultured for 24 h and the culture supernatants (CS) were assayed for hypoglycaemic activity. The activity was observed in the CD8+ T cells. The hypoglycaemia in JE-confirmed patients coincided with the gradual rise in circulating glucagon level, with no significant alterations in insulin, growth hormone and cortisol levels. The hTCHF was purified by ion exchange chromatography and the purified protein was observed as a approximately 25 kDa band on SDS-PAGE. Secretory hTCHF in the sera of patients and T cell CS was present in 88% of convalescent serum samples. We conclude that during the convalescent stage of JEV infection, a unique factor, hTCHF, is secreted by activated CD8+ T cells from patients and that this is responsible for the development of hypoglycaemia.  相似文献   
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Morphine Stimulates Mesangial Cell TNF-α and Nitrite Production   总被引:2,自引:0,他引:2  
Background: Intravenous opiate abusers are susceptible to develop heroin and HIV-associated nephropathies; however, the role of opiates in the development of these kidney lesions is not clear. Patients with opiate addiction are prone to recurrent infections. Methods: The effect of morphine was studied on the generation of TNF- with or without LPS (lipopolysaccharide) by cultured mouse mesangial cells. In addition, the effect of morphine was evaluated on mesangial cell nitrite production. To evaluate the role of opiate receptors, we studied the effect of naloxone and naltrexone on mesangial cell TNF- and nitrite production. To determine the role of TNF- on mesangial cell nitrite production, we examined the effect of anti-TNF- antibody on morphine-induced nitrite production. Assay of TNF- and nitrite production was carried by ELISA and Griess method respectively. Results: Morphine alone did not enhance the generation of TNF- by mesangial cells, however, an enhanced (P < 0.001) TNF- production was observed when mesangial cells were first treated with morphine for 18 h and then activated further with LPS. Maximum release of TNF- was seen at a concentration of 10–12 M of morphine. Opiate receptor antagonists (naloxone and naltrexone) inhibited the effect of morphine. Morphine also amplified (P < 0.0002) the effect of LPS on mesangial cell nitrite production. Anti-TNF- antibody attenuated morphine induced nitrite generation. Conclusion: We conclude that morphine stimulates the generation of TNF- by LPS-activated mesangial cells. This effect of morphine seems to be opiate receptor mediated and has a downstream effect in the form of mesangial cell nitrite generation. The present in vitro study provides the basis for a hypothesis that morphine may be playing a role in the development of heroin and HIV-associated nephropathies.  相似文献   
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Prolonged social isolation during the COVID-19 lockdown has adversely impacted the mental, social, and physical wellbeing of the global populace. Coping with mental and physical stressors amidst the global lockdown is especially strenuous for the Lesbian, Gay, Bisexual, Transgender, and more (LGBT+) community, who are frequently subjected to social stigma and minority stress. Systematic stigma and discrimination place LGBT+ individuals at higher risk for deleterious behaviors, such as substance abuse (e.g., injection drug use, smoking, alcohol) and risky sexual practices (e.g., anal/vaginal/oral sex). Maladaptive coping behaviors consequently increase the chances of HIV/AIDS risk among LGBT+ individuals, compared to heterosexual individuals. LGBT+ individuals Living with HIV/AIDS perpetually face higher rates of unemployment, income disparity, and intimate partner violence. Prolonged home confinement, and impaired accessibility to healthcare, legal, and criminal justice services during lockdown may deplete the quality of life of LGBT+ individuals Living with HIV/AIDS. Therefore, it is critical that multidisciplinary service providers, including health professionals, employers, social services providers, educational institutions and community organizations, move toward online service delivery, so that homebound HIV-positive LGBT+ individuals are secured with a wide range of care options. Non-judgemental, tele-counseling may bridge the gap to mental health services. Community clinics catering to HIV-positive and/or LGBT+ clients may consider precociously supplying essential amenities, such as Preexposure (PrEP)/postexposure prophylaxis (PEP), condoms, emergency contraception, and sterile needles. Lastly, efforts directed at the sustenance of at-risk/HIV-positive LGBT+ health should persevere, even after the pandemic.  相似文献   
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We show that interleukin 3 (IL-3) enhances the generation of tumor-specific cytotoxic T lymphocytes (CTLs) through the stimulation of host antigen-presenting cells (APCs). The BALB/c (H-2d) spontaneous lung carcinoma line 1 was modified by gene transfection to express ovalbumin as a nominal "tumor antigen" and to secrete IL-3, a cytokine enhancing myeloid development. IL-3-transfected tumor cells are less tumorigenic than the parental cell line, and tumor-infiltrating lymphocytes isolated from these tumors contain increased numbers of tumor-specific CTLs. By using B3Z86/90.14 (B3Z), a unique T-cell hybridoma system restricted to ovalbumin/H-2b and implanting the tumors in (BALB/c x C57BL/6)F1 (H-2d/b) mice, we demonstrate that the IL-3-transfected tumors contain an increased number of a rare population of host cells that can process and "re-present" tumor antigen to CTLs. Electron microscopy allowed direct visualization of these host APCs, and these studies, along with surface marker phenotyping, indicate that these APCs are macrophage-like. The identification of these cells and their enhancement by IL-3 offers a new opportunity for tumor immunotherapy.  相似文献   
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Loss-of-function due to expansion of a CGG repeat located in the 5''UTR of the FMR1 gene is the most frequent cause of fragile X syndrome. Less than 1% of individuals with fragile X syndrome have been reported to have a partial or full deletion or point mutation of the FMR1 gene. However, whether a copy number gain of the FMR1 gene could result in certain clinical phenotypes has not been fully investigated. Here, we report the case of a child who presented with developmental delay starting at 9 months of age, fine motor and speech delay, progressive seizures since 18 months of age and hyperactivity. Molecular workup identified a de novo microduplication in the Xq27.3 region, including the FMR1 gene and the ASFMR1 gene. The expression level of the FMR1 gene in peripheral blood did not differ from that of the controls. In addition, an inherited 363-kb duplication on the chromosome 1q44 region and an inherited deletion of 168 kb on the chromosome 4p15.31 region were detected. It is not clear whether these inherited copy number variations (CNVs) also have a modifying role in the clinical phenotype of this patient.  相似文献   
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Hematopoietic stem cell (HSC) release is positively regulated by the sympathetic nervous system through the β3 adrenergic receptor. Preclinical studies have demonstrated that the combination of desipramine and G‐CSF resulted in improved HSC mobilization. Here, we present the results of an open‐label single‐arm pilot study in patients with multiple myeloma undergoing autologous stem cell transplantation (ASCT) to assess the safety and efficacy of desipramine combined with G‐SCF to induce HSC mobilization. The primary endpoint was safety of the combination including engraftment kinetics. The secondary endpoint was the proportion of patients who collected ≥5 × 106 CD34+ cells/kg. Outcomes were compared with historical matched controls during the same time period with multiple myeloma mobilized with G‐CSF. All study patients received desipramine 100 mg daily for 7 days, starting 4 days prior to G‐CSF administration (D‐3) and continued taking it along with G‐CSF for a total of 7 days. Six of ten patients enrolled completed the protocol with minimal side effects. All of them achieved the target collection of 5 × 106 CD34 cells/kg in a median of 1.5 apheresis session with two patients needing additional plerixafor (16%), while 11 out of 13 patients (85%) achieved the target of 5 × 106 CD34 cells/kg in the historical control group in a median of 2 apheresis procedures and seven patients needed plerixafor (54%). The combination of desipramine and G‐CSF is safe and signals improved mobilization over G‐CSF alone, providing a possible alternative means of mobilization that needs further investigation.  相似文献   
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