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AIDS and Behavior - Little is known about the intersection of HIV stigma and substance use stigma. Using data from 188 HIV-positive people who inject drugs (PWID) in Russia, we examined the...  相似文献   
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Availability of the semiessential amino acid arginine is fundamental for the efficient function of human T lymphocytes. Tumor‐associated arginine deprivation, mainly induced by myeloid‐derived suppressor cells, is a central mechanism of tumor immune escape from T‐cell‐mediated antitumor immune responses. We thus assumed that transmembranous transport of arginine must be crucial for T‐cell function and studied which transporters are responsible for arginine influx into primary human T lymphocytes. Here, we show that activation via CD3 and CD28 induces arginine transport into primary human T cells. Both naïve and memory CD4+ T cells as well as CD8+ T cells specifically upregulated the human cationic amino acid transporter‐1 (hCAT‐1), with an enhanced and persistent expression under arginine starvation. When hCAT‐1 induction was suppressed via siRNA transfection, arginine uptake, and cellular proliferation were impaired. In summary, our results demonstrate that hCAT‐1 is a key component of efficient T‐cell activation and a novel potential target structure to modulate adaptive immune responses in tumor immunity or inflammation.  相似文献   
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Gestational hypertension (GHTN) and gestational diabetes mellitus (GDM) are both insulin resistance states. Perinatal outcome of GHTN or GDM alone are well established, but their combined effect on pregnancy outcome is underinvestigated. Our objective was to determine if pregnancies complicated by GHTN/GDM have higher rates of morbidity. We identified nulliparous women with singleton pregnancies delivering at 37 to 40 weeks of gestation from 1995 to 2004 from a database. Outcomes of pregnancies complicated by GHTN only, GDM only, or combined GHTN/GDM were compared with controls. Data analysis included the Mann-Whitney U test, the Kruskal-Wallis H test, and analysis of variance. Multivariate analysis was used to adjust for confounders. Of 14,880 patients, there were 11,349 controls, 2604 GHTN, 728 GDM, and 199 GHTN/GDM. After controlling for covariates, GHTN significantly increased cesarean section (C/S) rate (odd ratio [OR], 1.62; confidence interval [CI], 1.47 to 1.78), rates of admittance to the neonatal intensive care unit (NICU), and birth of large for gestational age (LGA) infants. GDM significantly increased C/S (OR, 1.42; CI 1.21 to 1.66), rates of NICU admission (OR, 1.32; CI, 1 to 1.75), birth of LGA (OR, 1.51; CI 1.14 to 1.98), and macrosomic infants (OR, 1.53; CI, 1.12 to 2.08). Rates of LGA infants (OR, 1.85; CI, 1.19 to 2.86) and C/S (OR, 2.03; CI, 1.52 to 2.71) were significantly increased with GHTN/GDM. We concluded that GHTN or GDM is associated with increased rates of adverse outcomes. Their coexistence further increases adverse perinatal outcomes.  相似文献   
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A 42-year-old female patient with history of secondary infertility was referred to our assisted conception unit for in vitro fertilization (IVF). Before her referral, she had two cycles of IVF at another centre; the first was unsuccessful and, after conceiving at the second attempt, the pregnancy was terminated at 14 weeks' gestation following a positive nuchal translucency scan and a diagnosis of trisomy 21 (Down syndrome) by a chorionic villous biopsy performed in the first trimester. The screening tests for trisomy 21 were offered to the patient in view of her advanced age. Subsequent karyotyping revealed that both partners had a normal chromosomal complement. Following genetic counselling, the couple were offered IVF treatment along with preimplantation genetic screening for trisomy 21. Four of the five embryos were suitable for biopsy, and one blastomere from each embryo was analyzed using fluorescent in situ hybridization for chromosome 21. The analysis revealed that two embryos had trisomy 21, one had monosomy 21, and only one embryo was diploid for chromosome 21. The single diploid embryo was transferred to the uterus on day 3, and resulted in an uneventful pregnancy and delivery of a healthy live-born male.  相似文献   
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