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111.
Kenneth K. Poon Bich N. Dang Jessica A. Davila Christine Hartman Thomas P. Giordano 《PloS one》2013,8(3)
Objective
Little is known about the treatment outcomes of undocumented Hispanic immigrants with HIV infection. We sought to compare the treatment outcomes of undocumented and documented patients 12-months after entering HIV care.Methods
We conducted a retrospective cohort study of antiretroviral-naive patients 18 years and older attending their first visit at Thomas Street Health Center in Houston, Texas, between 1/1/2003 and 6/30/2008. The study population of 1,620 HIV-infected adults included 186 undocumented Hispanic, 278 documented Hispanic, 986 Black, and 170 White patients. The main outcome measures were retention in care (quarter years with at least one completed HIV primary care provider visit) and HIV suppression (HIV RNA <400 copies/mL), both measured 12-months after entering HIV care.Results
Undocumented Hispanic patients had lower median initial CD4 cell count (132 cells/mm3) than documented Hispanic patients (166 cells/mm3; P = 0.186), Black patients (226 cells/mm3; P<0.001), and White patients (264 cells/mm3; P = 0.001). However, once in care, undocumented Hispanic patients did as well or better than their documented counterparts. One year after entering HIV care, undocumented Hispanics achieved similar rates of retention in care and HIV suppression as documented Hispanic and White patients. Of note, black patients were significantly less likely to have optimal retention in care (adjusted odds ratio [aOR] 0.65, CI = 0.45–0.94) or achieve HIV suppression (aOR 0.32, CI = 0.17–0.61) than undocumented Hispanics.Conclusions
Undocumented Hispanic persons with HIV infection enter care with more advanced disease than documented persons, suggesting testing and/or linkage to care efforts for this difficult-to-reach population need intensification. Once diagnosed, however, undocumented Hispanics have outcomes as good as or better than other racial/ethnic groups. Safety net providers for undocumented immigrants are vital for maintaining individual and public health. 相似文献112.
Xiangjing Fu Xiaolong Gao Shengfang He Di Huang Peng Zhang Xinglong Wang Shuxia Zhang Ruyi Dang Shuanghui Yin Enqi Du Zengqi Yang 《PloS one》2013,8(3)
Nanobodies (or variable domain of the heavy chain of the heavy-chain antibodies, VHHs) are single-domain antigen-binding fragments derived from camelid heavy chain antibodies. Their comparatively small size, monomeric behavior, high stability, high solubility, and ability to bind epitopes inaccessible to conventional antibodies make them especially suitable for many therapeutic and biotechnological applications. In this paper, for the first time, we created the immunized Camelus Bactrianus VHH yeast two-hybrid (Y2H) library according to the Clontech Mate & Plate library construction system. The transformation efficiency and titer of the VHH Y2H library were 7.26×106 cfu/3 µg and 2×109 cfu/ml, which met the demand for Y2H library screening. Using as an example the porcine circovirus type 2 (PCV2) Cap protein as bait, we screened 21 positive Cap-specific VHH sequences. Among these sequences, 7 of 9 randomly selected clones were strongly positive as indicated by enzyme-linked immunosorbent assay, either using PCV2 viral lysis or purified Cap protein as coated antigen. Additionally, the immunocytochemistry results further indicated that the screened VHHs could specifically detected PCV2 in the infected cells. All this suggests the feasibility of in vivo VHH throughput screening based on Y2H strategy. 相似文献
113.
Yaling Zhao Hong Yan Roger J. Marshall Shaonong Dang Ruihai Yang Qiang Li Xueying Qin 《PloS one》2013,8(4)
Objectives
To assess trends in average blood pressure levels and prevalence, awareness, treatment, and control of hypertension among adults in a rural area of Northwest China, and to determine associated risk factors.Methods
Four cross-sectional population-based surveys were conducted between 1982 and 2010 among randomly selected adults in rural areas of Hanzhong, in Northwest China. Data on blood pressure, body mass index, family history of hypertension, and socio-demographic and lifestyle characteristics were collected in similar way by trained investigators in four surveys. Data of 8575 participants aged 35–64 years was analyzed. Averages and proportions were adjusted for age and sex.Results
Average blood pressure in the population has increased since 1982 from 76.9 mm Hg to 79.6 mm Hg in 2010 (diastolic) and from 120.9 to 129.7 mm Hg (systolic). Prevalence of hypertension increased from 18.4% in 1982 to 30.5% in 2010, and awareness of hypertension increased from 16.8% to 38.4% in 2010. Treatment of hypertension increased from 1.0% in 1982 to 17.4% in 2010, and control of hypertension increased from 0.1% in 1982 to 3.5% in 2010. All these gradients were statistically significant (P<0.01 for trend). Population blood pressure and prevalence, awareness and treatment of hypertension were positively associated with increasing age, body mass index and having family history of hypertension.Conclusions
Average blood pressure levels and the prevalence, awareness, treatment and control of hypertension among adults in rural areas of Hanzhong have increased since 1982. However, awareness, treatment and control rates remain low. Public health programs and practical strategies are required to improve prevention and control of hypertension in rural Northwest China. In particular, attention should be given to the elderly and obese, and to those with a family history of hypertension, while raising awareness and treatment among younger adults. 相似文献114.
Vera Jankowski Markus T?lle Thi Nguyet Anh Tran Markus van der Giet Mirjam Schuchardt Kerstin Lehmann Doreen Janke Burkhard Flick Alberto Arduan Ortiz Ni?o Maria Dolores Sanchez Martin Tepel Walter Zidek Joachim Jankowski 《PloS one》2013,8(7)
The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U) from the secretome of human endothelial cells. The angiogenic effect of the endothelial secretome was partially reduced after incubation with alkaline phosphatase and abolished in the presence of suramin. In one fraction, purified to homogeneity by reversed phase and affinity chromatography, Up4U was identified by MALDI-LIFT-fragment-mass-spectrometry, enzymatic cleavage analysis and retention-time comparison. Beside a strong angiogenic effect on the yolk sac membrane and the developing rat embryo itself, Up4U increased the proliferation rate of endothelial cells and, in the presence of PDGF, of vascular smooth muscle cells. Up4U stimulated the migration rate of endothelial cells via P2Y2-receptors, increased the ability of endothelial cells to form capillary-like tubes and acts as a potent inducer of sprouting angiogenesis originating from gel-embedded EC spheroids. Endothelial cells released Up4U after stimulation with shear stress. Mean total plasma Up4U concentrations of healthy subjects (N = 6) were sufficient to induce angiogenic and proliferative effects (1.34±0.26 nmol L-1). In conclusion, Up4U is a novel strong human endothelium-derived angiogenic factor. 相似文献
115.
Wei Jia Rui Liu Jianguo Shi Bin Wu Wei Dang Ying Du Qiong Zhou Jianhua Wang Rui Zhang 《PloS one》2013,8(6)
Depression is one of the most frequent neuropsychiatric comorbidities associated with opiate addiction. Mitogen activated protein kinase (MAPK) and MAPK phosphatase (MKP) are involved in drug addiction and depression. However, the potential role of MAPK and MKP in depression caused by morphine withdrawal remains unclear. We utilized a mouse model of repeated morphine administration to examine the molecular mechanisms that contribute to prolonged withdrawal induced depressive-like behaviors. Depressive-like behaviors were significant at 1 week after withdrawal and worsened over time. Phospho-ERK (extracellular signal-regulated protein kinase) was decreased and MKP-1 was elevated in the hippocampus, and JNK (c-Jun N-terminal protein kinase), p38 (p38 protein kinase) and MKP-3 were unaffected. A pharmacological blockade of MKP-1 by intra-hippocampal sanguinarine (SA) infusion prevented the development of depressive-like behaviors and resulted in relatively normal levels of MKP-1 and phospho-ERK after withdrawal. Our findings support the association between hippocampal MAPK phosphorylation and prolonged morphine withdrawal-induced depression, and emphasize the MKP-1 as an negative regulator of the ERK phosphorylation that contributes to depression. 相似文献
116.
Hai Dang Nguyen Jordan Becker Yee Mon Thu Michael Costanzo Elizabeth N. Koch Stephanie Smith Kyungjae Myung Chad L. Myers Charles Boone Anja-Katrin Bielinsky 《PloS one》2013,8(6)
Deficiency in DNA ligase I, encoded by CDC9 in budding yeast, leads to the accumulation of unligated Okazaki fragments and triggers PCNA ubiquitination at a non-canonical lysine residue. This signal is crucial to activate the S phase checkpoint, which promotes cell cycle delay. We report here that a pol30-K107 mutation alleviated cell cycle delay in cdc9 mutants, consistent with the idea that the modification of PCNA at K107 affects the rate of DNA synthesis at replication forks. To determine whether PCNA ubiquitination occurred in response to nicks or was triggered by the lack of PCNA-DNA ligase interaction, we complemented cdc9 cells with either wild-type DNA ligase I or a mutant form, which fails to interact with PCNA. Both enzymes reversed PCNA ubiquitination, arguing that the modification is likely an integral part of a novel nick-sensory mechanism and not due to non-specific secondary mutations that could have occurred spontaneously in cdc9 mutants. To further understand how cells cope with the accumulation of nicks during DNA replication, we utilized cdc9-1 in a genome-wide synthetic lethality screen, which identified RAD59 as a strong negative interactor. In comparison to cdc9 single mutants, cdc9 rad59Δ double mutants did not alter PCNA ubiquitination but enhanced phosphorylation of the mediator of the replication checkpoint, Mrc1. Since Mrc1 resides at the replication fork and is phosphorylated in response to fork stalling, these results indicate that Rad59 alleviates nick-induced replication fork slowdown. Thus, we propose that Rad59 promotes fork progression when Okazaki fragment processing is compromised and counteracts PCNA-K107 mediated cell cycle arrest. 相似文献
117.
118.
Modeling energy and charge transfer in DNA has been a challenging issue because of many conformations DNA can take. Due to its simplicity, we propose a discrete variational approach to study the charge transfer mechanism in DNA based on the Holstein-Su-Schrieffer-Heeger model. It is shown that bright solitary waves may propagate through the DNA and the variational approximation provides explicit relations between experimental parameters and important characteristics of the waves such as amplitude, width, chirp and homogenous phase, and energy. Our analytical predictions are confirmed by intensive numerical simulations with a good accuracy. 相似文献
119.
Qiong Li Fan Liu Rui Dang Chunyue Feng Rui Xiao Ye Hua Wei Wang Zhi Jia Dayong Liu 《Journal of cellular physiology》2020,235(12):9691-9701
We wished to evaluate whether epigenetic modifiers have a beneficial effect on treating experimental periodontitis and mechanisms for regulating the cell fate of mesenchymal stem cells (MSCs) in inflammatory microenvironments. We isolated MSCs from healthy and inflamed gingival tissues to investigate whether trichostatin A (TSA) could improve osteogenic differentiation and resolve inflammation in vitro. The tissue regenerative potentials were evaluated when treated with a temperature-dependent, chitosan-scaffold-encapsulated TSA, in a rat model of periodontitis. After induction with the conditioned medium, TSA treatment increased the osteogenic differentiation potential of inflamed MSCs and healthy MSCs. In addition, interleukin-6 and interleukin-8 levels in supernatants were significantly decreased after TSA treatment. Moreover, TSA promoted osteogenic differentiation by inhibiting nuclear factor-κB (p65) DNA binding in MSCs. In rats with experimental periodontitis, 7 weeks after local injections of chitosan-scaffold-encapsulated TSA, histology and microcomputed tomography showed a significant increase in alveolar bone volume and less inflammatory infiltration compared with vehicle-treated rats. The concentrations of interferon-γ and interleukin-6 were significantly decreased in the gingival crevicular fluid after TSA treatment. This study demonstrated that TSA had anti-inflammatory properties and could promote periodontal tissue repair, which indicated that epigenetic modifiers hold promise as a potential therapeutic option for periodontal tissue repair. 相似文献
120.
The sequence of the chloroplast genome, which is inherited maternally, contains useful information for many scientific fields such as plant systematics, biogeography and biotechnology because its characteristics are highly conserved among species. There is an increase in chloroplast genomes of angiosperms that have been sequenced in recent years. In this study, the nucleotide sequence of the chloroplast genome (cpDNA) of Veratrum patulum Loes. (Melanthiaceae, Liliales) was analyzed completely. The circular double-stranded DNA of 153,699 bp consists of two inverted repeat (IR) regions of 26,360 bp each, a large single copy of 83,372 bp, and a small single copy of 17,607 bp. This plastome contains 81 protein-coding genes, 30 distinct tRNA and four genes of rRNA. In addition, there are six hypothetical coding regions (ycf1, ycf2, ycf3, ycf4, ycf15 and ycf68) and two open reading frames (ORF42 and ORF56), which are also found in the chloroplast genomes of the other species. The gene orders and gene contents of the V. patulum plastid genome are similar to that of Smilax china, Lilium longiflorum and Alstroemeria aurea, members of the Smilacaceae, Liliaceae and Alstroemeriaceae (Liliales), respectively. However, the loss rps16 exon 2 in V. patulum results in the difference in the large single copy regions in comparison with other species. The base substitution rate is quite similar among genes of these species. Additionally, the base substitution rate of inverted repeat region was smaller than that of single copy regions in all observed species of Liliales. The IR regions were expanded to trnH_GUG in V. patulum, a part of rps19 in L. longiflorum and A. aurea, and whole sequence of rps19 in S. china. Furthermore, the IGS lengths of rbcL-accD-psaI region were variable among Liliales species, suggesting that this region might be a hotspot of indel events and the informative site for phylogenetic studies in Liliales. In general, the whole chloroplast genome of V. patulum, a potential medicinal plant, will contribute to research on the genetic applications of this genus. 相似文献