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11.
Hardy Christopher Fairley Christopher K. Ong Jason J. Vodstrcil Lenka A. Bradshaw Catriona S. Snow Anthony Chow Eric P. F. 《Archives of sexual behavior》2022,51(5):2497-2507
Rises in condomless anal sex among men who have sex with men (MSM) have been reported over the last decade but there is less certainty about the role that drugs, alcohol, play in this change. We examined the changes in drug and alcohol use among 22,255 MSM reporting condomless anal sex at Melbourne Sexual Health Centre in 2011–2017. There was a 7% annual increase in using drugs before and/or during condomless anal sex but a 3% annual reduction in condomless anal sex while drunk. MSM taking PrEP were more likely to report condomless anal sex with drug use (AOR: 1.21; 95%CI: 1.07–1.37) and alcohol use (AOR: 1.29; 95%CI: 1.14–1.46) compared with MSM not taking PrEP.
相似文献12.
Lenka L Allan Koren K Mann Raymond A Matulka Heui-Young Ryu Jennifer J Schlezinger David H Sherr 《Toxicological sciences》2003,76(2):357-365
Environmental polycyclic aromatic hydrocarbons (PAH) and related halogenated hydrocarbons are immunotoxic in a variety of systems. In a model system of B lymphopoiesis, PAH exposure rapidly induces apoptosis in CD43- pre-B and CD43+ pro/pre-B cells. Apoptosis induction by 7,12-dimethylbenzo[a]anthracene (DMBA) is dependent upon AhR+ bone marrow stromal cells and likely involves DMBA metabolism within the stromal cell. However, it is not known if PAH-treated stromal cells release free metabolites or soluble factors that may directly induce B cell death or if the effector death signal is delivered by stromal cell-B cell contact. Here, we demonstrate that supernatants from DMBA-treated bone marrow stromal cells contain an activity capable of inducing apoptosis in pro/pre-B cells cocultured with stromal cells. This activity (1) is not produced when stromal cells are cotreated with DMBA and alpha-naphthoflavone (alpha-NF), an aryl hydrocarbon receptor (AhR) and cytochrome P-450 inhibitor, (2) is > or = 50 kDa, (3) is trypsin and heat sensitive, and (4) is dependent on AhR+ stromal cells, which in turn deliver the effector death signal to pro/pre-B cells. The results (1) argue against a role for a soluble, stromal cell-derived cytokine as the effector of PAH-induced pro/pre-B cell death, (2) exclude the possibility of a free metabolite acting directly on AhR- pro/pre-B cell targets, and (3) suggest the elaboration by stromal cells of a relatively stable, DMBA metabolite-protein complex capable of acting on other stromal cells at some distance. Collectively, these studies suggest that, while stromal cell products, e.g., metabolite-protein complexes, may affect the function of distant stromal cells, the effector death signal delivered by stromal cells to bone marrow B cells is mediated by cell-cell contact. 相似文献
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ABSTRACT: The transforming growth factor (TGF-beta) family of growth factors controls an immense number of cellular responses and figures prominently in development and homeostasis of most human tissues. Work over the past decades has revealed significant insight into the TGF-beta signal transduction network, such as activation of serine/threonine receptors through ligand binding, activation of SMAD proteins through phosphorylation, regulation of target genes expression in association with DNA-binding partners and regulation of SMAD activity and degradation. Disruption of the TGF-beta pathway has been implicated in many human diseases, including solid and hematopoietic tumors. As a potent inhibitor of cell proliferation, TGF-beta acts as a tumor suppressor; however in tumor cells, TGF-beta looses anti-proliferative response and become an oncogenic factor. This article reviews current understanding of TGF-beta signaling and different mechanisms that lead to its impairment in various solid tumors and hematological malignancies. 相似文献
15.
Carla Sharp Amanda Venta Lochner Marais Donald Skinner Molefi Lenka Joe Serekoane 《AIDS and behavior》2014,18(6):1174-1185
Due to the HIV/AIDS pandemic which has left 12 million children orphaned in Sub-Saharan Africa, children are at increased risk for mental health problems. Currently, no validity data exist for any screening measure of emotional-behavior disorders in pre-adolescent children in Sub-Saharan Africa. The aims of the current study were to evaluate the construct validity of the caregiver-, teacher-, and self-report versions of the one-page Strengths and Difficulties Questionnaire (SDQ) in 466 orphans in South Africa between the ages of 7 and 11 (M age = 9.23 years, SD = 1.33, 51.93 % female) and to provide, for the first time, clinical cut-offs for this population. Findings demonstrated support for the caregiver SDQ, but not the teacher and self-report versions. We provide clinical cut-offs, but caution their use before further research is conducted. There remains a critical need for further psychometric studies of the SDQ in the developing world. 相似文献
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Cancer and Metastasis Reviews - Branched-chain amino acids (BCAA) are essential amino acids utilized in anabolic and catabolic metabolism. While extensively studied in obesity and diabetes, recent... 相似文献
17.
Lenka Sedlarikova Barbora Gromesova Veronika Kubaczkova Lenka Radova Jana Filipova Jiri Jarkovsky Lucie Brozova Roberta Velichova Martina Almasi Miroslav Penka Renata Bezdekova Martin Stork Zdenek Adam Ludek Pour Marta Krejci Petr Kuglík Roman Hajek Sabina Sevcikova 《European journal of haematology》2017,99(3):223-233
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Lenka Langhansova Premysl Landa Zsofia Kutil Jan Tauchen Petr Marsik Jan Rezek 《Food and Agricultural Immunology》2017,28(2):343-353
Myrica rubra Sieb. et Zucc. is a valuable fruit tree that is used in Chinese, Japanese and Taiwanese traditional medicine. We investigated the anti-inflammatory activity of M. rubra leaves extracted with four different solvents. Total phenolics were determined using the Folin–Ciocalteu method. Extracts were investigated for their inhibitory activity toward the pro-inflammatory enzymes cyclooxygenase-1 and -2 (COX-1, COX-2) and 5-lipoxygenase (5-LOX). The ethanol extract of M. rubra leaves demonstrated a strong inhibition of prostaglandin E2 (PGE2) biosynthesis catalyzed by both COX-1 (93.42%) and COX-2 (75.71%) and leukotriene B4 (LTB4) formation catalyzed by 5-LOX (82.72%). Further we identified selective COX-1 inhibition by the n-butanol and aqueous fractions of the ethanol extract (with an IC50 for COX-1 inhibition of 1.07 and 0.71?µg?mL?1 , respectively) and dual 5-LOX/COX inhibition by the ethyl acetate fraction (with an IC50 of 3.29 for COX-1, 2.54 for COX-2 and 8.30?µg?mL?1 for 5-LOX). 相似文献
20.
Health effects of dietary phospholipids 总被引:1,自引:0,他引:1
Daniela Küllenberg Lenka A Taylor Michael Schneider Ulrich Massing 《Lipids in health and disease》2012,11(1):1-16
Beneficial effects of dietary phospholipids (PLs) have been mentioned since the early 1900's in relation to different illnesses and symptoms, e.g. coronary heart disease, inflammation or cancer. This article gives a summary of the most common therapeutic uses of dietary PLs to provide an overview of their approved and proposed benefits; and to identify further investigational needs. From the majority of the studies it became evident that dietary PLs have a positive impact in several diseases, apparently without severe side effects. Furthermore, they were shown to reduce side effects of some drugs. Both effects can partially be explained by the fact that PL are highly effective in delivering their fatty acid (FA) residues for incorporation into the membranes of cells involved in different diseases, e.g. immune or cancer cells. The altered membrane composition is assumed to have effects on the activity of membrane proteins (e.g. receptors) by affecting the microstructure of membranes and, therefore, the characteristics of the cellular membrane, e.g. of lipid rafts, or by influencing the biosynthesis of FA derived lipid second messengers. However, since the FAs originally bound to the applied PLs are increased in the cellular membrane after their consumption or supplementation, the FA composition of the PL and thus the type of PL is crucial for its effect. Here, we have reviewed the effects of PL from soy, egg yolk, milk and marine sources. Most studies have been performed in vitro or in animals and only limited evidence is available for the benefit of PL supplementation in humans. More research is needed to understand the impact of PL supplementation and confirm its health benefits. 相似文献