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41.
Arunagiri Kuha Deva Magendhra Rao Vittal Rangan Arvinden Deepa Ramasamy Krishna Patel Balaiah Meenakumari Priya Ramanathan Shirley Sundersingh Velusami Sridevi Thangarajan Rajkumar Zdenko Herceg Harsha Gowda Samson Mani 《Journal of cellular and molecular medicine》2021,25(8):3912-3921
Breast cancer is a major cause of cancer-related death in women worldwide. Non-coding RNAs are a potential resource to be used as an early diagnostic biomarker for breast cancer. Circular RNAs are a recently identified group of non-coding RNA with a significant role in disease development with potential utility in diagnosis/prognosis in cancer. In this study, we identified 26 differentially expressed circular RNAs associated with early-stage breast cancer. RNA sequencing and two circRNA detection tools (find_circ and DCC) were used to understand the circRNA expression signature in breast cancer. We identified hsa_circ_0006743 (circJMJD1C) and hsa_circ_0002496 (circAPPBP1) to be significantly up-regulated in early-stage breast cancer tissues. Co-expression analysis identified four pairs of circRNA-miRNA (hsa_circ_0023990 : hsa-miR-548b-3p, hsa_circ_0016601 : hsa_miR-1246, hsa_circ_0001946 : hsa-miR-1299 and hsa_circ_0000117:hsa-miR-502-5p) having potential interaction. The miRNA target prediction and network analysis revealed mRNA possibly regulated by circRNAs. We have thus identified circRNAs of diagnostic implications in breast cancer and also observed circRNA-miRNA interaction which could be involved in breast cancer development. 相似文献
42.
Dorcas Ibukun Akinloye Regina Ngozi Ugbaja Oluwatosin Adebisi Dosumu Samson Adisa Rahman Emmanuel Ifeanyichukwu Ugwor Adewale Segun James Olushola Oladapo Oyesile Mary Bunmi Bada 《Biochemistry and Biophysics Reports》2021
This present research investigated variations in lipid profiles and important biomarkers of tissue damage in response to graded concentrations of alcohol administration in male Wistar rats. Group A (control) received distilled water while group B, C and D received 30%, 40% and 50% (v/v) alcohol respectively. Five rats each from groups A-D were sacrificed after day(s) 1, 7, 14, 21 and 28 of administration. A significant increase was observed at day 28 for serum cholesterol by 79% (group B), 78% (group C) and 47% (group D) together with serum phospholipid 58% (group B), 50% (group C) and 92% (group D). Serum triacylglycerol increased by 71% (group B), 43% (group C) and 16% (group D) at day 21, while concentration of serum albumin decreased at day 28 by 40.9% (group B), 50.2% (group C), 53.3% (group D) respectively when compared with control (group A). Serum aminotransferases and alkaline phosphatase specific activities, as well as creatinine and uric acid concentration increased in a concentration-dependent manner, following alcohol administration. Though most of these effects induced by alcohol were time- and concentration-dependent, 40% alcohol appear to be more stable, giving results consistent with alcohol-induced damages, with minimal mortality. This study therefore further validated dyslipidemia and imbalance in clinical biomarkers as hallmarks of tissue damage induced by excessive alcohol consumption with an insight on the time- and concentration-response relationship between alcohol consumption and its toxicity. 相似文献
43.
Megan J. Dobro Rachel Y. Samson Zhiheng Yu John McCullough H. Jane Ding Parkson Lee-Gau Chong Stephen D. Bell Grant J. Jensen 《Molecular biology of the cell》2013,24(15):2319-2327
The endosomal-sorting complex required for transport (ESCRT) is evolutionarily conserved from Archaea to eukaryotes. The complex drives membrane scission events in a range of processes, including cytokinesis in Metazoa and some Archaea. CdvA is the protein in Archaea that recruits ESCRT-III to the membrane. Using electron cryotomography (ECT), we find that CdvA polymerizes into helical filaments wrapped around liposomes. ESCRT-III proteins are responsible for the cinching of membranes and have been shown to assemble into helical tubes in vitro, but here we show that they also can form nested tubes and nested cones, which reveal surprisingly numerous and versatile contacts. To observe the ESCRT–CdvA complex in a physiological context, we used ECT to image the archaeon Sulfolobus acidocaldarius and observed a distinct protein belt at the leading edge of constriction furrows in dividing cells. The known dimensions of ESCRT-III proteins constrain their possible orientations within each of these structures and point to the involvement of spiraling filaments in membrane scission. 相似文献
44.
Yann Lamarre Marie-Laure Lalanne-Mistrih Marc Romana Nathalie Lemonne Daniele Mougenel Xavier Waltz Beno?t Tressières Maryse Etienne-Julan Vanessa Tarer Marie-Dominique Hardy-Dessources Philippe Connes 《PloS one》2013,8(6)
Patients with sickle cell anemia (SCA) have usually lower diastolic, systolic and mean blood pressure (BP) than the general population. However, BP values ≥120/70 mmHg considerably increase the risk for acute and chronic complications in SCA. The aim of this study was to identify biological factors associated with relative hypertension in adults with SCA. We compared the hematological, lipid and hemolytic profiles, as well as blood viscosity, between SCA patients with normal BP (<120/70 mmHg, n = 54) and those with relative hypertension (BP≥120/70 mmHg, n = 43). Our results demonstrated that male gender (OR: 3.49; 95%CI 1.20 to 10.16, p<0.05), triglycerides (OR: 9.19; 95% CI 2.29 to 36.95, p<0.01), blood viscosity (OR: 1.35; 95% CI 1.01 to 1.81, p<0.05) and body mass index (OR: 1.37; 95% CI 1.14 to 1.64, p<0.01) were independent risks factors for relative hypertension in SCA. No association was found between the BP status and the positive history of painful vaso-occlusive crisis or acute chest syndrome. An association between triglycerides level and the occurrence of these two major acute complications was detected. Our study suggests that male gender, increased triglycerides level, BMI and blood viscosity could increase the risk for developing relative hypertension in SCA. In addition, our results support a role of moderately elevated triglycerides in the pathophysiology of vaso-occlusive events. 相似文献
45.
Xavier Waltz Marc Romana Marie-Dominique Hardy-Dessources Yann Lamarre Lydia Divialle-Doumdo Marie Petras Vanessa Tarer Régine Hierso Kizzy-Clara Baltyde Beno?t Tressières Marie-Laure Lalanne-Mistrih Fréderic Maillard Olivier Hue Maryse Etienne-Julan Philippe Connes 《PloS one》2013,8(10)
The six-minute walk test is a well-established submaximal exercise reflecting the functional status and the clinical severity of sickle cell patients. The aim of the present cross-sectional study was to investigate the biological determinants of the six-minute walk test performance in children with sickle cell anemia. Hematological and hemorheological parameters, pulmonary function and the six-minute walk test performance were determined in 42 children with sickle cell anemia at steady state. The performance during the six-minute walk test was normalized for age, sex and height and expressed as percentage of the predicted six-minute walk distance. We showed that a high level of anemia, a low fetal hemoglobin expression and low red blood cell deformability were independent predictors of a low six-minute walk test performance. This study describes for the first time the impact of blood rheology in the six-minute walk test performance in children with sickle cell anemia. 相似文献
46.
Frances M. Cowan Sibongile Mtetwa Calum Davey Elizabeth Fearon Jeffrey Dirawo Ramona Wong-Gruenwald Theresa Ndikudze Samson Chidiya Clemens Benedikt Joanna Busza James R. Hargreaves 《PloS one》2013,8(10)
Objective(S)
To determine the HIV prevalence and extent of engagement with HIV prevention and care among a representative sample of Zimbabwean sex workers working in Victoria Falls, Hwange and Mutare.Design
Respondent driven sampling (RDS) surveys conducted at each site.Methods
Sex workers were recruited using respondent driven sampling with each respondent limited to recruiting 2 peers. Participants completed an interviewer-administered questionnaire and provided a finger prick blood sample for HIV antibody testing. Statistical analysis took account of sampling method.Results
870 women were recruited from the three sites. HIV prevalence was between 50 and 70%. Around half of those confirmed HIV positive were aware of their HIV status and of those 50-70% reported being enrolled in HIV care programmes. Overall only 25-35% of those with laboratory-confirmed HIV were accessing antiretroviral therapy. Among those reporting they were HIV negative, 21-28% reported having an HIV test in the last 6 months. Of those tested HIV negative, most (65-82%) were unaware of their status. Around two-thirds of sex workers reported consistent condom use with their clients. As in other settings, sex workers reported high rates of gender based violence and police harassment.Conclusions
This survey suggests that prevalence of HIV is high among sex workers in Zimbabwe and that their engagement with prevention, treatment and care is sub-optimal. Intensifying prevention and care interventions for sex workers has the potential to markedly reduce HIV and social risks for sex workers, their clients and the general population in Zimbabwe and elsewhere in the region. 相似文献47.
The actinobacterial transcription factor RbpA binds to the principal sigma subunit of RNA polymerase
48.
49.
Tasha Daley Samson N. Omoregie Vincent Wright Felix O. Omoruyi 《Biological trace element research》2013,151(3):400-405
Cadmium is an environmental pollutant of increasing worldwide concern. It has been reported to be high in the soil where food crops are grown in some parishes of Jamaica. Surprisingly, no adverse effect of cadmium has been reported among the Jamaican population. However, phytic acid has also been shown to be high in some food crops grown in Jamaica. In this study, we evaluated the effects of phytic acid (1 %) and exercise on the metabolism of cadmium (5 mg cadmium/kg body weight) in rats. Five groups of rats were fed as follows: rats fed control diet, control diet supplemented with cadmium and subjected to exercise, control diet supplemented with phytic acid plus cadmium and subjected to exercise, control diet supplemented with cadmium plus phytic acid, and control diet supplemented with cadmium only. The animals were fed for 4 weeks and then sacrificed. Blood samples were collected for some biochemical assays. Percentage weight loss (28.42 %) was greatest in the group that had cadmium supplement only. The group fed control diet supplemented with cadmium only displayed increased liver enzymes and electrolytes except for the significant decrease in bicarbonate compared to other test groups. Similarly, blood urea nitrogen and uric acid were increased in the group fed cadmium supplement only compared to other test groups. Total cholesterol trended downwards in the test groups compared to control. These observations suggest that consumption of diet high in phytic acid with relatively high physical activity may be protective against the adverse effects of cadmium. 相似文献
50.
Vincent E. J. Jassey Caroline Meyer Christine Dupuy Nadine Bernard Edward A. D. Mitchell Marie-Laure Toussaint Marc Metian Auriel P. Chatelain Daniel Gilbert 《Microbial ecology》2013,66(3):571-580
Although microorganisms are the primary drivers of biogeochemical cycles, the structure and functioning of microbial food webs are poorly studied. This is the case in Sphagnum peatlands, where microbial communities play a key role in the global carbon cycle. Here, we explored the structure of the microbial food web from a Sphagnum peatland by analyzing (1) the density and biomass of different microbial functional groups, (2) the natural stable isotope (δ 13C and δ 15N) signatures of key microbial consumers (testate amoebae), and (3) the digestive vacuole contents of Hyalosphenia papilio, the dominant testate amoeba species in our system. Our results showed that the feeding type of testate amoeba species (bacterivory, algivory, or both) translates into their trophic position as assessed by isotopic signatures. Our study further demonstrates, for H. papilio, the energetic benefits of mixotrophy when the density of its preferential prey is low. Overall, our results show that testate amoebae occupy different trophic levels within the microbial food web, depending on their feeding behavior, the density of their food resources, and their metabolism (i.e., mixotrophy vs. heterotrophy). Combined analyses of predation, community structure, and stable isotopes now allow the structure of microbial food webs to be more completely described, which should lead to improved models of microbial community function. 相似文献