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21.
Nathalie Thieblemont Laurence Weiss Hoss M. Sadeghi Claudia Estcourt Nicole Haeffner-Cavaillon 《European journal of immunology》1995,25(12):3418-3424
Infection with the human immunodeficiency virus HIV-1 is associated with the expansion of a CD14lowCD16high monocyte subset in peripheral blood. This subset, which represents a minor subpopulation of monocytes in healthy individuals, increases during HIV infection and, in patients with AIDS, may represent up to 40% of the total circulating monocyte cell population. The CD14lowCD16high circulating monocytes co-express MAX.1, p150,95 and HLADR which are typical of tissue macrophage markers. These cells also express higher levels of intracellular interleukin (IL)-1α and tumor necrosis factor (TNF)-α than the CD14highCD16low monocyte population from the same patients. The CD14lowCD16high cells also express low levels of CD35, CD11a and CD4 in common with normal monocytes. When cultured in vitro, monocytes from HIV-seropositive individuals differentiated within a few hours into an elongated fibroblastoid shape characteristic of migratory cells. Our results suggest that the expansion of the CD14lowCD16high monocyte subset, which produce high amounts of TNF-α and IL-1α, may participate in the immune dysfunction observed during HIV infection. 相似文献
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23.
Villamor E Saathoff E Msamanga G O'Brien ME Manji K Fawzi WW 《Journal of acquired immune deficiency syndromes (1999)》2005,38(5):622-626
OBJECTIVES: To examine whether wasting during pregnancy, as measured by weight loss and low weight gain, is associated with increased mother-to-child transmission (MTCT) of HIV-1. METHODS: This was a cohort study in Dar es Salaam, Tanzania, among 957 HIV-1-infected pregnant women. Weight was measured at the first prenatal visit and every month thereafter until delivery. Weight loss was defined as a weekly rate of weight gain =0 and low weight gain as a weekly rate >0 and =166 g/wk. The incidences of presumptive intrauterine transmission (HIV status at birth) and presumptive intrapartum and early breast-feeding transmission (HIV status at 6 weeks) were examined in relation to baseline anthropometric characteristics and weight change during pregnancy using 2xn tables and multivariable binomial regression. RESULTS: Compared with women who gained >/=167 g/wk, weight loss during pregnancy was related to higher risk of intrauterine MTCT (adjusted relative risk [RR] = 2.32, 95% CI = 1.23-4.36, P = 0.009), HIV positive at birth or fetal death (RR = 2.13, 95% CI = 1.40-3.24, P = 0.0004), and HIV positive at birth or early neonatal death (RR = 1.96, 95% CI = 1.26-3.07, P = 0.003). The rate of weight gain during the 3rd trimester was inversely related to the risk of intrapartum/early breast-feeding transmission (adjusted P value, test for trend = 0.05). CONCLUSIONS: Weight loss during pregnancy increases the risk of early MTCT. Identifying causes of wasting during pregnancy may provide clues for new strategies to prevent MTCT. 相似文献
24.
B L Hodes J M Schietroma S S Lane J Sadeghi D Cunningham D Stambolian 《Metabolic, pediatric, and systemic ophthalmology (New York, N.Y. : 1985)》1985,8(2-3):39-42
Deficiency of the enzyme, galactokinase, is a recognized cause of "juvenile" lens opacities; these opacities are felt to be its only clinical expression. The deficiency itself is inherited as an autosomal recessive and as such is expected to be clinically manifest in the homozygote. We have recently demonstrated cataracts and associated bilateral macular deposits in a white male who is heterozygous for the deficiency of the enzyme and whose dietary intake of milk and its products is extremely high. To our knowledge, intraretinal deposits have not previously been described in patients with galactokinase deficiency, and their clinical significance and biochemical makeup can only be speculative. Dietary restriction of galactose is recommended for all individuals proven to be deficient in this enzyme, whether homozygous or heterozygous. 相似文献
25.
Karim A. Alkadhi 《Naunyn-Schmiedeberg's archives of pharmacology》1986,332(3):230-235
Summary The effect of the hemicholium-3 analog, DMAE, on endplate currents (EPC) was investigated in the transected cutaneous pectoris muscle of the frog using a conventional two-microelectrode voltage clamp. At a low concentration (5 M), DMAE produced a long-lasting decrease in the rate constant of decay () and an increase in the peak current amplitude (Ip). At higher concentrations (10–100 M), DMAE produced biphasic changes characterized by a transient, marked decrease of and increase of Ip followed by a long-lasting marked increase of and decrease of Ip. When DMAE was removed from the bath recovery from block was asymmetrical in that recovered more quickly than did Ip. Pretreatment with neostigmine or collagenase partially antagonized the initial effects without affecting the steady state effects of DMAE, indicating that the initial effects of DMAE may be, at least in part, due to inhibition of the enzyme acetylcholinesterase. The drug reverses the normal voltage dependence of without altering the single exponential nature of decay of the EPC. The inward EPC was more markedly blocked than outward EPC, resulting in a highly non-linear current-voltage relation with Ip decreasing with increasing hyperpolarization. This effect may indicate that DMAE causes a voltage-dependent block of closed acetylcholine-activated ion channels. 相似文献
26.
Rania El Fekih James Hurley Vasisht Tadigotla Areej Alghamdi Anand Srivastava Christine Coticchia John Choi Hazim Allos Karim Yatim Juliano Alhaddad Siawosh Eskandari Philip Chu Albana B. Mihali Isadora T. Lape Mauricio P. Lima Filho Bruno T. Aoyama Anil Chandraker Kassem Safa James F. Markmann Leonardo V. Riella Richard N. Formica Johan Skog Jamil R. Azzi 《Journal of the American Society of Nephrology : JASN》2021,32(4):994
BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making. 相似文献
27.
Patrick M. Lec Abhishek Venkataramana Andrew T. Lenis Katherine E. Fero Vidit Sharma Vishnukamal Golla Kiran Gollapudi Jeremy Blumberg Karim Chamie 《Urologic oncology》2021,39(3):194.e17-194.e24
BackgroundHigh-risk ureteral tumors represent an understudied subset of upper tract urothelial carcinoma, whose surgical management can range from a radical nephroureterectomy (NU) to segmental ureterectomy (SU).ObjectivesTo evaluate contemporary trends in the management of high-risk ureteral tumors, the utilization of lymphadenectomy and peri-operative chemotherapy, and their impact on overall survival (OS).Design, setting, and participantsWe performed a retrospective cohort study of patients in the National Cancer Database from years 2006 to 2013 with clinically localized high-risk ureteral tumors treated with NU or SU.Outcome measurements and statistical analysisChi-squared tests were utilized to assess differences in clinicodemographic features and peri-operative treatment delivery between SU and NU cohorts. Cochran-Armitage tests and linear regressions were performed to evaluate temporal trends in treatment utilization. Multivariable logistic regression models were employed to assess predictors of treatment delivery. Multivariable Cox proportional hazards models evaluated associations with OS.ResultsOf the 1,962 patients included, NU was more commonly performed than SU (72.4%, 1,421/1,962 vs. 27.6%, 541/1,962). Only 22.7% (446/1,962) of the population underwent lymphadenectomy, and 24.8% (271/1,092) of those with advanced pathology (≥pT2 or pN+) received adjuvant chemotherapy. Lymphadenectomy was associated with improved OS in NU patients when more than 3 nodes were removed (hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.39–0.89). Receipt of adjuvant chemotherapy for advanced pathology had no impact OS in both the NU (HR 1.10, 95% CI 0.84–1.44) and SU (HR 0.94, 95% CI 0.61–1.46) cohorts. Performance of SU was not associated with poorer OS on multivariable analysis (HR 1.02, 95% CI 0.89–1.21, P = 0.83).ConclusionOur study suggests that SU may be an appropriate alternative to NU for the management of high-risk ureteral tumors. Further, lymphadenectomy may play an important role at the time of NU, and adjuvant chemotherapy is infrequently utilized in patients with advanced pathology. 相似文献
28.
Drolshagen H. Bhavaraju A. Kalkwarf K. J. Karim S. A. Reif R. Sexton K. W. Jensen H. K. 《Hernia》2021,25(5):1259-1264
Hernia - Inguinal hernia repair is one of the most common surgical operations, yet the optimal treatment strategy remains undefined. Treatment of symptomatic inguinal hernias include both surgical... 相似文献
29.
30.
Janine Jewanraj Sinaye Ngcapu Farzana Osman Veron Ramsuran Maryam Fish Andile Mtshali Ravesh Singh Leila E Mansoor Salim S Abdool Karim Quarraisha Abdool Karim JoAnn S Passmore Lenine J P Liebenberg 《Journal of the International AIDS Society》2021,24(6)
IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women. 相似文献