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101.
PurposeAssess prevalence of myopia and identify associated risk factors in urban school children.MethodsThis was a cross-sectional study screening children for sub-normal vision and refractive errors in Delhi. Vision was tested by trained health workers using ETDRS charts. Risk factor questionnaire was filled for children with vision <6/9.5, wearing spectacles and for a subset (10%) of randomly selected children with normal vision. All children with vision <6/9.5 underwent cycloplegic refraction. The prevalence of myopia <-0.5 diopters was assessed. Association of risk factors and prevalence of myopia was analyzed for children with myopia and randomly selected non myopic children and adjusted odds ratio values for all risk factors were estimated.ResultsA total number of 9884 children were screened with mean age of 11.6 + 2.2 years and 66.8% boys. Prevalence of myopia was 13.1% with only 320 children (24.7%) wearing appropriate spectacles. Mean myopic spherical error was -1.86 + 1.4 diopters. Prevalence of myopia was higher in private schools compared to government schools (p<0.001), in girls vs. boys (p = 0.004) and among older (> 11 years) children (p<0.001). There was a positive association of myopia with studying in private schools vs. government schools (p<0.001), positive family history (p< 0.001) and higher socio-economic status (p = 0.037). Positive association of presence of myopia was observed with children studying/reading > 5 hours per day (p < 0.001), watching television > 2 hours / day (p < 0.001) and with playing computer/video/mobile games (p < 0.001). An inverse association with outdoor activities/playing was observed with children playing > 2 hours in a day.ConclusionMyopia is a major health problem in Indian school children. It is important to identify modifiable risk factors associated with its development and try to develop cost effective intervention strategies.  相似文献   
102.
The Ranibizumab for the Treatment of Choroidal Neovascularisation (CNV) Secondary to Pathological Myopia (PM): an Individualized Regimen (REPAIR) trial was a prospective study exploring the efficacy and safety of intravitreal ranibizumab 0.5 mg using an individualized treatment regimen over 12 months. The current study investigated the impact of treatment with ranibizumab as needed (pro re nata [PRN]) on individuals with myopic choroidal neovascularization (mCNV) in the REPAIR study, using patient-reported outcome measures (PROMs) for treatment satisfaction and well-being. This study included 65 adults with mCNV and a best-corrected visual acuity (BCVA) letter score of 24–78 in the study eye. Patients completed the Macular Disease Treatment Satisfaction Questionnaire (MacTSQ) at months 1, 6 and 12, and the 12-item Well-Being Questionnaire (W-BQ12) at baseline and months 1, 6 and 12. Subgroup analyses investigated the relationship between PROM scores and treatment in the better- or worse-seeing eye (BSE/WSE), number of injections received, baseline BCVA, BCVA improvement and age. Pearson correlations between change in BCVA, MacTSQ scores and W-BQ12 scores were calculated. The main outcome measures were treatment satisfaction measured with the MacTSQ (score 0–72) and well-being measured with the W-BQ12 (score 0–36). Treatment satisfaction significantly increased over the study period (p = 0.0001). Mean MacTSQ scores increased by 9.7 and 10.0 in patients treated in their WSE and BSE, respectively. Treatment satisfaction was highest in individuals receiving only one injection at month 1; however, by month 12, scores were similar across injection subgroups. Patients aged 68 years or older had the highest MacTSQ scores. Well-being scores also significantly increased over the study period (p = 0.03). Mean W-BQ12 scores increased by 1.7 in patients treated in their WSE and by 2.1 in patients treated in their BSE. Individuals aged 40 years or younger had the greatest increases in general well-being. Patients who experienced stable or improved BCVA at month 12 had greater increases in W-BQ12 scores than those who experienced a decrease. Correlations between BCVA, MacTSQ scores and W-BQ12 scores were largely non-significant. In conclusion, treatment satisfaction and well-being increased during treatment with ranibizumab PRN. Although directly comparable data are limited for the MacTSQ and W-BQ12 in mCNV, these results complement PROM outcomes reported in related studies.  相似文献   
103.
The downstream functions of the DNA binding tumor suppressor p53 vary depending on the cellular context, and persistent p53 activation has recently been implicated in tumor suppression and senescence. However, genome-wide information about p53-target gene regulation has been derived mostly from acute genotoxic conditions. Using ChIP-seq and expression data, we have found distinct p53 binding profiles between acutely activated (through DNA damage) and chronically activated (in senescent or pro-apoptotic conditions) p53. Compared to the classical ‘acute’ p53 binding profile, ‘chronic’ p53 peaks were closely associated with CpG-islands. Furthermore, the chronic CpG-island binding of p53 conferred distinct expression patterns between senescent and pro-apoptotic conditions. Using the p53 targets seen in the chronic conditions together with external high-throughput datasets, we have built p53 networks that revealed extensive self-regulatory ‘p53 hubs’ where p53 and many p53 targets can physically interact with each other. Integrating these results with public clinical datasets identified the cancer-associated lipogenic enzyme, SCD, which we found to be directly repressed by p53 through the CpG-island promoter, providing a mechanistic link between p53 and the ‘lipogenic phenotype’, a hallmark of cancer. Our data reveal distinct phenotype associations of chronic p53 targets that underlie specific gene regulatory mechanisms.  相似文献   
104.
Altered placental function as a consequence of aberrant imprinted gene expression may be one mechanism mediating the association between low birth weight and increased cardiometabolic disease risk. Imprinted gene expression is regulated by epigenetic mechanisms, particularly DNA methylation (5mC) at differentially methylated regions (DMRs). While 5-hydroxymethylcytosine (5hmC) is also present at DMRs, many techniques do not distinguish between 5mC and 5hmC. Using human placental samples, we show that the expression of the imprinted gene CDKN1C associates with birth weight. Using specific techniques to map 5mC and 5hmC at DMRs controlling the expression of CDKN1C and the imprinted gene IGF2, we show that 5mC enrichment at KvDMR and DMR0, and 5hmC enrichment within the H19 gene body, associate positively with birth weight. Importantly, the presence of 5hmC at imprinted DMRs may complicate the interpretation of DNA methylation studies in placenta; future studies should consider using techniques that distinguish between, and permit quantification of, both modifications.  相似文献   
105.
BackgroundThe disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coincident infections.Conclusions/SignificanceWe were unable to find a significant effect of W. bancrofti infection or its treatment on HIV clinical course or surrogate markers of HIV disease progression though we recognized that our study was limited by the smaller than predicted sample size and by the use of ART in half of the patients. Treatment of W. bancrofti coinfection in HIV positive subjects (as is usual in mass drug administration campaigns) did not represent an increased risk to the subjects, and should therefore be considered for PLWHA living in W. bancrofti endemic areas.

Trial Registration

ClinicalTrials.gov NCT00344279  相似文献   
106.
Endothelium plays a fundamental role in maintaining the vascular tone by releasing various biochemical factors that modulate the contractile and relaxatory behavior of the underlying vascular smooth muscle, regulation of inflammation, immunomodulation, platelet aggregation, and thrombosis. Endothelium regulates these cellular processes by activating endothelial nitric oxide synthase (eNOS) responsible for nitric oxide (NO) production. eNOS is constitutively expressed in ECs in response to humoral, mechanical or pharmacological stimulus. eNOS activity is regulated mainly by protein-protein interactions and multisite phosphorylations. The phosphorylation state of specific serine, threonine and tyrosine residues of the enzyme plays a pivotal role in regulation of eNOS activity. Perturbations of eNOS phosphorylation have been reported in a number of diseases thereby emphasizing the importance of regulation of eNOS activity. This review summarizes the mechanism of eNOS regulation through multi-site phosphorylation in different pathologies. Attempts have been made to highlight phosphorylation of eNOS at various residues, regulation of the enzyme activity via posttranslational modifications and its implications on health and disease.  相似文献   
107.
Traditionally, Tinospora cordifolia (Willd.) Hook. F. & Thomson (Menispermaceae), Ocimum sanctum L. (Lamiaceae), Moringa oleifera Lam. (Moringaceae), and Phyllanthus niruri L. (Euphorbiaceae) are some of the commonly used medicinal plants in India for curing ailments ranging from common cold, skin diseases, and dental infections to major disorders like diabetes, hypertension, jaundice, rheumatism, etc. To understand and correlate their medicinal use, trace element studies on the aqueous extract of these medicinal plants have been carried out using particle-induced X-ray emission technique. A 2-MeV proton beam was used to identify and characterize major and minor elements namely Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, and Sr in them. Results have revealed that these elements are present in varying concentrations in the selected plants. Notable results include very high concentrations of Cl, K, and Ca in all the leaf samples, appreciable levels of Mn in all plants, high Zn content in T. cordifolia, and the aqueous extract of Moringa leaves compared to others and relative higher concentrations of Cr in all the plants.  相似文献   
108.
109.
Apicomplexan parasites obligatorily invade and multiply within eukaryotic cells. Phylogenetically, they are related to a group of algae which, during their evolution, have acquired a secondary endosymbiont. This organelle, which in the parasite is called the apicoplast, is highly reduced compared to the endosymbionts of algae, but still contains many plant-specific biosynthetic pathways. The malaria parasite Plasmodium falciparum infects mammalian erythrocytes which are devoid of intracellular compartments and which largely lack biosynthetic pathways. Despite the limited resources of nutrition, the parasite grows and generates up to 32 merozoites which are the infectious stages of the complex life cycle. A large part of the intra-erythrocytic development takes place in the so-called parasitophorous vacuole, a compartment which forms an interface between the parasite and the cytoplasm of the host cell. In the course of parasite growth, the host cell undergoes dramatic alterations which on one hand contribute directly to the symptoms of severe malaria and which, on the other hand, are also required for parasite survival. Some of these alterations facilitate the acquisition of nutrients from the extracellular environment which are not provided by the host cell. Here, we describe the cell biologically unique interactions between an intracellular eukaryotic pathogen and its metabolically highly reduced host cell. We further discuss current models to explain the appearance of pathogen-induced novel physiological properties in a host cell which has lost its genetic programme.  相似文献   
110.
Tctex-1, a light-chain component of the cytoplasmic dynein motor complex, can function independently of dynein to regulate multiple steps in neuronal development. However, how dynein-associated and dynein-free pools of Tctex-1 are maintained in the cell is not known. Tctex-1 was recently identified as a Gbetagamma-binding protein and shown to be identical to the receptor-independent activator of G protein signaling AGS2. We propose a novel role for the interaction of Gbetagamma with Tctex-1 in neurite outgrowth. Ectopic expression of either Tctex-1 or Gbetagamma promotes neurite outgrowth whereas interfering with their function inhibits neuritogenesis. Using embryonic mouse brain extracts, we demonstrate an endogenous Gbetagamma-Tctex-1 complex and show that Gbetagamma co-segregates with dynein-free fractions of Tctex-1. Furthermore, Gbeta competes with the dynein intermediate chain for binding to Tctex-1, regulating assembly of Tctex-1 into the dynein motor complex. We propose that Tctex-1 is a novel effector of Gbetagamma, and that Gbetagamma-Tctex-1 complex plays a key role in the dynein-independent function of Tctex-1 in regulating neurite outgrowth in primary hippocampal neurons, most likely by modulating actin and microtubule dynamics.  相似文献   
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