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71.
Maria Alícia Carrillo-Sepúlveda Graziela S. Ceravolo Cristina R. Furstenau Priscilla de Souza Monteiro Zuleica Bruno-Fortes Maria Helena Carvalho Francisco R. Laurindo Rita C. Tostes R. Clinton Webb Maria Luiza M. Barreto-Chaves 《PloS one》2013,8(4)
Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3) that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC) relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS) plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R), a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper). These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC). Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII), which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L) for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium. 相似文献
72.
Tomá? Venit Rastislav Dzijak Al?běta Kalendová Michal Kahle Jana Roho?ková Volker Schmidt Thomas Rülicke Birgit Rathkolb Wolfgang Hans Alexander Bohla Oliver Eickelberg Tobias Stoeger Eckhard Wolf Ali ?nder Yildirim Valérie Gailus-Durner Helmut Fuchs Martin Hrabě de Angelis Pavel Hozák 《PloS one》2013,8(4)
73.
Sumon Kumar Das Mohammod Jobayer Chisti Sayeeda Huq Mohammad Abdul Malek Lana Vanderlee Guddu Kaur Mohammed Abdus Salam Tahmeed Ahmed Abu Syed Golam Faruque Abdullah Al Mamun 《PloS one》2013,8(8)
Background
The present study aimed to determine the clinical characteristics and etiology of overweight and obese (OO) individuals with diarrhea attending an urban Dhaka Hospital, International Centre for Diarrheal Disease Research (icddr,b), Bangladesh.Methods
Total of 508 under-5 children, 96 individuals of 5–19 years and 1331 of >19 years were identified as OO from the Diarrheal Disease Surveillance System (DDSS) between 1993–2011. Two comparison groups such as well-nourished and malnourished individuals from respective age stratums were selected.Results
Isolation rate of rotavirus was higher among OO under-5 children compared to malnourished group (46% vs. 28%). Rotavirus infection among OO individuals aged 5–19 years (9% vs. 3%) (9% vs. 3%) and >19 years (6% vs. 4%) (6% vs. 3%) was higher compared to well-nourished and malnourished children. Conversely, Vibrio cholerae was lower among all OO age groups compared to well-nourished and malnourished ones. Shigella (4% vs. 6%) (4% vs. 8%), and Campylobacter (3% vs. 5%) (3% vs. 5%) were lower only among OO in >19 years individuals compared to their counterparts of the same age stratum. Salmonella was similarly isolated in all age strata and nutritional groups. In multinomial logistic regression among under-5 children, significant association was observed only with use of antimicrobials at home [OR-1.97] and duration of hospital stay [OR-0.68]. For individuals aged 5–19 years, use of antimicrobials at home (OR-1.83), some or severe dehydration (OR-3.12), having received intravenous saline (OR-0.46) and rotavirus diarrhea (OR-2.96) were found to be associated with OO respectively. Moreover, significant associations were also found for duration of diarrhea before coming to hospital (>24 hours) (OR-1.24), Shigella (OR-0.46), and Campylobacter (OR-0.58) among >19 years OO individuals along with other associated co-variates in 5–19 years group (all p<0.05).Conclusion and significance
Higher proportion of OO were infected with rotavirus and a greater proportion of them used antimicrobials before coming to the hospital. 相似文献74.
Fatema Alzahrani Hiroyuki Kuwahara Yongkang Long Mohammed Al-Owain Mohamed Tohary Moeenaldeen AlSayed Mohammed Mahnashi Lana Fathi Maha Alnemer Mohamed H. Al-Hamed Gabrielle Lemire Kym M. Boycott Mais Hashem Wenkai Han Almundher Al-Maawali Feisal Al Mahrizi Khalid Al-Thihli Xin Gao Fowzan S. Alkuraya 《American journal of human genetics》2020,107(6):1178
75.
Kaoutar Aboukhalid Abdeslam Lamiri Monika Agacka‐Mołdoch Teresa Doroszewska Ahmed Douaik Mohamed Bakha Joseph Casanova Félix Tomi Nathalie Machon Chaouki Al Faiz 《化学与生物多样性》2016,13(9):1126-1139
Origanum compactum L. (Lamiaceae) is one of the most important medicinal species in term of ethnobotany in Morocco. It is considered as a very threatened species as it is heavily exploited. Its domestication remains the most efficient way to safeguard it for future generations. For this purpose, wide evaluation of the existing variability in all over the Moroccan territory is required. The essential oils of 527 individual plants belonging to 88 populations collected from the whole distribution area of the species in Morocco were analyzed by GC/MS. The dominant constituents were carvacrol (0 – 96.3%), thymol (0 – 80.7%), p‐cymene (0.2 – 58.6%), γ‐terpinene (0 – 35.2%), carvacryl methyl ether (0 – 36.2%), and α‐terpineol (0 – 25.8%). While in the Middle Atlas region and the Central Morocco mainly carvacrol type samples were found, much higher chemotypic diversity was encountered within samples from the north part of Morocco (occidental and central Rif regions). The high chemical polymorphism of plants offers a wide range for selection of valuable chemotypes, as a part of breeding and domestication programs of this threatened species. 相似文献
76.
Suhad M. Bahijri Hanan A. Jambi Rajaa M. Al Raddadi Gordon Ferns Jaakko Tuomilehto 《PloS one》2016,11(4)
BackgroundType 2 (T2DM) is believed to be common in Saudi Arabia, but data are limited. In this population survey, we determined the prevalence of T2DM and prediabetes.ResultsAge and sex standardized prevalence of prediabetes was 9.0% (95% CI 7.5–10.5); 9.4% (7.1–11.8) in men and 8.6% (6.6–10.6) in women. For DM it was 12.1% (10.7–13.5); 12.9% (10.7–13.5) in men and 11.4% (9.5–13.3) in women. The prevalence based on World Population as standard was 18.3% for DM and 11.9% for prediabetes. The prevalence of DM and prediabetes increased with age. Of people aged ≥50 years 46% of men and 44% of women had DM. Prediabetes and DM were associated with various measures of adiposity. DM was also associated with and family history of dyslipidemia in women, cardiovascular disease in men, and with hypertension, dyslipidemia and family history of diabetes in both sexes.DiscussionAge was the strongest predictor of DM and prediabetes followed by obesity. Of people aged 50 years or over almost half had DM and another 10–15% had prediabetes leaving only a small proportion of people in this age group with normoglycemia. Since we did not use an oral glucose tolerance test the true prevalence of DM and prediabetes is thus likely to be even higher than reported here. These results demonstrate the urgent need to develop primary prevention strategies for type 2 diabetes in Saudi Arabia. 相似文献
77.
Greg Clark Josh Russell Peter Enyeart Brant Gracia Aimee Wessel Inga Jarmoskaite Damon Polioudakis Yoel Stuart Tony Gonzalez Al MacKrell Stacia Rodenbusch Gwendolyn M. Stovall Josh T. Beckham Michael Montgomery Tania Tasneem Jack Jones Sarah Simmons Stanley Roux 《PLoS biology》2016,14(2)
Both scientists and the public would benefit from improved communication of basic scientific research and from integrating scientists into education outreach, but opportunities to support these efforts are limited. We have developed two low-cost programs—"Present Your PhD Thesis to a 12-Year-Old" and "Shadow a Scientist”—that combine training in science communication with outreach to area middle schools. We assessed the outcomes of these programs and found a 2-fold benefit: scientists improve their communication skills by explaining basic science research to a general audience, and students'' enthusiasm for science and their scientific knowledge are increased. Here we present details about both programs, along with our assessment of them, and discuss the feasibility of exporting these programs to other universities. 相似文献
78.
Beatriz Martín-Fernández Alfonso Rubio-Navarro Isabel Cortegano Sandra Ballesteros Mario Alía Pablo Cannata-Ortiz Elena Olivares-álvaro Jesús Egido Belén de Andrés María Luisa Gaspar Natalia de las Heras Vicente Lahera Juan Antonio Moreno 《PloS one》2016,11(1)
We aimed to evaluate macrophages heterogeneity and structural, functional and inflammatory alterations in rat kidney by aldosterone + salt administration. The effects of treatment with spironolactone on above parameters were also analyzed. Male Wistar rats received aldosterone (1 mgkg-1d-1) + 1% NaCl for 3 weeks. Half of the animals were treated with spironolactone (200 mg kg-1d-1). Systolic and diastolic blood pressures were elevated (p<0.05) in aldosterone + salt–treated rats. Relative kidney weight, collagen content, fibronectin, macrophage infiltrate, CTGF, Col I, MMP2, TNF-α, CD68, Arg2, and SGK-1 were increased (p<0.05) in aldosterone + salt–treated rats, being reduced by spironolactone (p<0.05). Increased iNOS and IFN-γ mRNA gene expression (M1 macrophage markers) was observed in aldosterone + salt rats, whereas no significant differences were observed in IL-10 and gene ArgI mRNA expression or ED2 protein content (M2 macrophage markers). All the observed changes were blocked with spironolactone treatment. Macrophage depletion with liposomal clodronate reduced macrophage influx and inflammatory M1 markers (INF-γ or iNOS), whereas interstitial fibrosis was only partially reduced after this intervention, in aldosterone plus salt-treated rats. In conclusion, aldosterone + salt administration mediates inflammatory M1 macrophage phenotype and increased fibrosis throughout mineralocorticoid receptors activation. 相似文献
79.
Purpose of Review
Invasive candidiasis (IC) is the leading cause of fungal infections in solid organ transplant recipients (SOT). In this article, we aim to review the epidemiology, risk factors, presentation, and management of IC in this population.Recent Findings
Certain risk factors have been associated with IC in SOT recipients. Targeted antifungal prophylaxis for SOT recipients at the highest risk of infection is currently recommended although the choice and duration of antifungal agents remain controversial. Early diagnosis and monitoring of IC in SOT recipients are critical to achieve better outcomes and prevent serious complications. Non-culture-based diagnostic modalities have been introduced to aid in earlier and more accurate diagnosis.Summary
The use of azoles for prophylaxis or treatment in SOT recipients allowed for selection of resistance and increased the incidence of non-albicans Candida. Drug–drug interactions, cost, and risk of resistance are to be considered when using more potent or newer antifungal agents.80.
Plant strategy and life‐history theories make different predictions about reproductive efficiency under competition. While strategy theory suggests under intense competition iteroparous perennial plants delay reproduction and semelparous annuals reproduce quickly, life‐history theory predicts both annual and perennial plants increase resource allocation to reproduction under intense competition. We tested (1) how simulated competition influences reproductive efficiency and competitive ability (CA) of different plant life histories and growth forms; (2) whether life history or growth form is associated with CA; (3) whether shade avoidance plasticity is connected to reproductive efficiency under simulated competition. We examined plastic responses of 11 herbaceous species representing different life histories and growth forms to simulated competition (spectral shade). We found that both annual and perennial plants invested more to reproduction under simulated competition in accordance with life‐history theory predictions. There was no significant difference between competitive abilities of different life histories, but across growth forms, erect species expressed greater CA (in terms of leaf number) than other growth forms. We also found that shade avoidance plasticity can increase the reproductive efficiency by capitalizing on the early life resource acquisition and conversion of these resources into reproduction. Therefore, we suggest that a reassessment of the interpretation of shade avoidance plasticity is necessary by revealing its role in reproduction, not only in competition of plants. 相似文献