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101.
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103.
Jennes W Sawadogo S Koblavi-Dème S Vuylsteke B Maurice C Roels TH Chorba T Nkengasong JN Kestens L 《AIDS research and human retroviruses》2002,18(3):171-177
The role of beta-chemokines in controlling HIV replication in vivo is still controversial. Therefore, the association between HIV-1 plasma viral load and the capacity of CD4(+) and CD8(+) T cells to produce beta-chemokines was studied in 28 antiretroviral drug-na?ve HIV-1-infected female sex workers in Abidjan, C?te d'Ivoire. Percentages of beta-chemokine-positive T cells were measured in peripheral blood mononuclear cells by flow cytometry after intracellular staining for RANTES (regulated on activation, normal T expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta. HIV-1-infected subjects had higher percentages of MIP-1alpha- and MIP-1beta-positive CD4(+) and CD8(+) T cells (p < 0.02) and of RANTES-positive CD8(+) T cells (p = 0.054) than uninfected controls. Percentages of RANTES- and MIP-1beta-positive CD8(+) T cells correlated directly with HIV-1 plasma viral load (p < 0.02). Percentages of beta-chemokine-positive CD4(+) and CD8(+) T cells correlated directly with percentages of HLA-DR-positive T cells (p < 0.02) and inversely (except RANTES in CD4(+) T cells) with absolute numbers of CD4(+) T cells (p < 0.05) in peripheral blood. These data indicate that increased percentages of beta-chemokine-producing T cells in HIV-1-infected subjects correlate with disease progression and are a sign of viremia-driven chronic T cell activation. 相似文献
104.
Gardner DS Pearce S Dandrea J Walker R Ramsay MM Stephenson T Symonds ME 《Hypertension》2004,43(6):1290-1296
An adverse environment around conception and implantation influences later fetal growth and development to term in humans and sheep. Indeed, preimplantation undernutrition of rats elevated the systolic blood pressure of the resultant adult offspring. In this study, adult cardiovascular function is examined in a slower growing, non-litter-bearing species after peri-implantation undernutrition. Eight ewes were fed to 50% equivalent food intake of 12 control ewes from 1 to 30 days (term approximately 147 days) only. Following consumption of an adequate diet to term, natural lambing, and then weaning, resting cardiovascular status and baroreflex function were examined in the resultant young adult offspring. Birth weight and postnatal growth to 1 year of age were unaffected by early undernutrition; however, nutrient-restricted sheep had increased pulse pressure, a reduced rate pressure product, and a leftward shift in their baroreflex function curve. Baroreflex sensitivity during angiotensin II infusion was also blunted in early nutrient-restricted sheep but the tachycardia following a reduction in central blood pressure appeared potentiated, relative to controls. The data suggest that peri-implantation undernutrition may program long-term cardiovascular dysfunction that ultimately increases the risk of hypertension later in life. An increase in regional angiotensin II activity during this critical early phase of development is a likely candidate mechanism for the effects observed. The data have broad implications for the health outcome of those offspring from mothers who were poorly nourished during early, often unknown pregnancy and for embryos artificially manipulated because of infertility treatment. 相似文献
105.
This study examined factors associated with the intention to take an HIV test among men who have sex with men (MSM) in South Korea. An internet website-based survey was conducted among users of the only and largest online MSM website between 20 July 2016, and 20 August 2016. A total of 2915 participants completed the survey and answered questions related to sociodemographic information, health behaviors, sexual behaviors, and HIV testing history. Of these, 2587 (88.7%) participants responded as having an intention to take an HIV test. A multivariable logistic regression analysis revealed the following as having reduced the intention to undergo HIV testing: very good subjective health status and no sexual interactions during the last 6 months (Adjusted odds ratios [AOR] 0.45 and 0.54, respectively). In contrast, increased intention to take an HIV test was associated with being 20–29 years old, 30–39 years old, not paying or receiving money for sex, having a history of HIV testing, and taking an HIV test once per 12 months (AOR 2.64, 2.13, 1.54, 1.81, and 2.17, respectively). In conclusion, HIV testing among MSM in this study was associated with age, subjective health status, sex(es) of one’s sexual partner(s) during the last 6 months, sexual risk behaviors, HIV testing history, and undergoing regular HIV testing. 相似文献
106.
Lee SY Kim JS Lee JM Kwon SS Kim KH Moon HS Song JS Park SH Kim YK 《Pulmonary pharmacology & therapeutics》2008,21(1):14-19
Airway smooth muscle growth contributes to the mechanism of airway hyperresponsiveness (AHR) in asthma. Although current steroid use demonstrates anti-inflammatory activity, there is little reported on the action of corticosteroid on smooth muscle of the asthmatic airway. The present study investigated the effect of inhaled corticosteroid on the thickening of airway smooth muscle in bronchial asthma. We developed a mouse model of airway remodeling including smooth muscle thickening in which ovalbumin (OVA)-sensitized female BALB/c-mice were repeatedly exposed to intranasal OVA administration twice a week for 3 months. Mice were treated intranasally with fluticasone during the OVA challenge. Mice chronically exposed to OVA developed sustained eosinophilic airway inflammation compared with control mice. In addition, the mice chronically exposed to OVA developed features of airway remodeling, including thickening of the peribronchial smooth muscle layer. Intranasal administration of fluticasone inhibited the development of eosinophilic inflammation, and importantly, thickening of the smooth muscle layer. Moreover, intranasal fluticasone treatment reduced the transforming growth factor (TGF)-beta 1 level in bronchoalveolar lavage fluid and regulated active TGF-beta 1 signaling with a reduction in the expression of phospho-Smad2/3 and the concomitant up-regulation of Smad7 in lung tissue sections. These results suggest that intranasal administration of fluticasone can modulate the remodeling of airway smooth muscle via regulation of TGF-beta 1 production and active TGF-beta 1 signaling. 相似文献
107.
Lindeman RD Romero L Liang HC Hundley R Baumgartner R Koehler K Garry P 《Geriatric Nephrology and Urology》1998,8(3):123-130
Introduction. The purpose of this study was to compare the prevalences of urinary abnormalities, notably proteinuria and microalbuminuria, in a randomly selected, biethnic population of Hispanic and nonHispanic white males and females and to determine the effects of diabetes, hypertension, and coronary heart disease on these prevalence rates. Methods. A survey of health and health related issues was conducted on 883 volunteers, mean age 74.1 years, selected randomly from the Medicare rolls of Bernallilo County (Albuquerque), New Mexico. The sample consisted of nearly equal numbers of Hispanic and nonHispanic white males and females. A dipstick urinalysis and test for microalbuminuria was performed on a clean void, untimed urine sample as a part of a 4-hour interview/examination. Results. Of the 696 participants with complete databases, 10.5% had 1+ or greater proteinuria (30 mg/dL or more) by convential urinalysis dipstick and 19.8% had microalbuminuria (50 mg/L or more) by Micral Chemstrip® methodology. Participants with diabetes mellitus (Odds Ratio (OR) 2.54, Confidence Interval (CI) 1.71–3.76, p < 0.001), and/or hypertension (OR 2.09, 95% CI 1.46–3.01, p < 0.001) were more likely to have microalbuminuria than participants without either of these conditions. After adjusting for the presence of diabetes and hypertension, there was a trend toward an increased prevalence of coronary heart disease (OR 1.23, 95% CI 0.84–1.81 p = 0.28) in those with microalbuminuria, but this did not reach levels of statistical significance. Conclusions. Hispanics, even after adjusting for a higher prevalence of diabetes, and for small differences in prevalences of hypertension and coronary heart disease, had more microalbuminuria than nonHispanic whites, and males had more microalbuminuria than females. 相似文献
108.
Jennes W Sawadogo S Koblavi-Dème S Vuylsteke B Maurice C Roels TH Chorba T Nkengasong JN Kestens L 《The Journal of infectious diseases》2003,187(2):206-214
Cellular factors that may protect against human immunodeficiency virus (HIV) infection were investigated in 27 HIV-exposed seronegative (ESN) female sex workers (FSWs) and 27 HIV-seronegative female blood donors. Compared with blood donors, ESN FSWs had significantly decreased expression levels of C-X-C chemokine receptor 4 (CXCR4), but not of C-C chemokine receptor 5, on both memory (P<.001) and naive (P=.041) CD4(+) T cells. CXCR4 down-regulation was associated with prolonged duration of commercial sex work by ESN FSWs. CD38 expression on CD8(+) T cells was significantly increased among ESN FSWs, compared with that among blood donors (P=.017). There were no differences in HLA-DR and CD62L expression between blood donors and ESN FSWs. Proportions of T cells producing the beta-chemokines RANTES (regulated on activation, normally T cell-expressed and -secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta or the cytokines interleukin (IL)-2, IL-4, interferon-gamma, and tumor necrosis factor-alpha, were similar in the 2 groups. These data indicate that ESN FSWs differ from HIV-seronegative female blood donors with respect to immunological factors that have no clear protective potential against HIV transmission. 相似文献
109.
Karen Y. Kwok Timmy L. S. Choi Wai Him Kwok Ming Yip Lau Elvis M. K. Leung Gary N. W. Leung Jenny K. Y. Wong Terence S. M. Wan Farrington F. Adrian Anil Prabhu Emmie N. M. Ho 《Drug testing and analysis》2020,12(9):1274-1286
The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse). 相似文献
110.
Jenny K.Y. Wong George H.M. Chan Timmy L.S. Choi Karen Y. Kwok Ming Y. Lau Gary N.W. Leung Terence S.M. Wan Emmie N.M. Ho 《Drug testing and analysis》2020,12(7):900-917
A high‐throughput method has been developed for the doping control analysis of 124 drug targets, processing up to 154 horse urine samples in as short as 4.5 h, from the time the samples arrive at the laboratory to the reporting deadline of 30 min before the first race, including sample receipt and registration, preparation and instrument analysis and data vetting time. Sample preparation involves a brief enzyme hydrolysis step (30 min) to detect both free and glucuronide‐conjugated drug targets. This is followed by extraction using solid‐supported liquid extraction (SLE) and analysis using liquid chromatography–high‐resolution mass spectrometry (LC–HRMS). The entire set‐up comprised of four sets of Biotage Extrahera automation systems for conducting SLE and five to six sets of Orbitrap for instrumental screening using LC–HRMS. Suspicious samples flagged were subject to confirmatory analyses using liquid chromatography–triple quadrupole mass spectrometry. The method comprises 124 drug targets from a spectrum of 41 drug classes covering acidic, basic and neutral drugs. More than 85% of the targets had limits of detection at or below 5 ng/mL in horse urine, with the lowest at 0.02 ng/mL. The method was validated for qualitative identification, including specificity, sensitivity, extraction recovery and precision. Method applicability was demonstrated by the successful detection of different drugs, namely (a) butorphanol, (b) dexamethasone, (c) diclofenac, (d) flunixin and (e) phenylbutazone, in post‐race or out‐of‐competition urine samples collected from racehorses. This method was developed for pre‐race urine testing in Hong Kong; however, it is also suitable for testing post‐race or out‐of‐competition urine samples, especially when a quick total analysis time is desired. 相似文献