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871.
A. B. Imbs N. A. Latyshev V. I. Svetashev A. V. Skriptsova Thanh Tat Le Minh Quan Pham Van Son Nguyen Long Quoc Pham 《Russian Journal of Marine Biology》2012,38(4):339-345
The fatty acid (FA) composition and the content of the prostaglandin PGE2 were determined in the red algae Gracilaria vermiculophylla and G. austramaritima from Peter the Great Bay (Sea of Japan), as well as in G. tenuistupitata, G. ?hangii, and G. bailiniae from lagoons in southern Vietnam (in the South China Sea). Polyunsaturated FA (PUFA) comprised 49?C56% of the total FAs in algae from the Sea of Japan, while in algae from the South China Sea their share was 20% at most. The content of arachidonic acid (20:4n-6) in the total FAs of G. vermiculophylla was as high as 45.4%, while the level of 20:4n-6 in Gracilaria from coastal waters of Vietnam did not exceed 12.5%. G. austramaritima stood out for its high content of eicosapentaenoic acid 20:5n-3 (33.5%). The ratios of 20:4n-6/20:5n-3 in G. vermiculophylla, G. austramaritima, G. tenuistupitata, G. changii, and G. bailiniae were 10.6, 0.3, 3.9, 4.0, and 1.5, respectively. The content of PGE2 was the highest (286 ??g/g dry weight) in G. vermiculophylla from the Sea of Japan and did not exceed 20 ??g/g dry weights in other Gracilaria species. This study showed that it is possible to introduce G. vermiculophylla from the Sea of Japan into the mariculture of northern Vietnam. In the experiment, during 3 weeks of cultivation, the biomass of introduced Gracilaria increased 1.2?C1.3 times in a sea lagoon in Vietnam and 1.5?C2 times in an aquarium; the algal growth rates were 1.57 ± 0.21% per day. In cultivated Gracilaria, the level of 20:4n-6 decreased to 5.9% (20:4n-6/20:5n-3 = 2.3) and the level of PGE2 decreased to 12 ??g/g in dry weight. The PUFA compositions of G. vermiculophylla from various natural populations differed insignificantly; however, the stress caused by introduction led to a sharp reduction in the content of 20:4n-6, which was probably connected with a decreased biosynthesis rate of PUFAs of the n-6 series. At the same time, approximately equal amounts of PGE2 methyl ester were extracted from natural and cultivated G. vermiculophylla after treatment by a method proposed for obtaining prostaglandins. Thus, the cultivation conditions evidently did not influence the prostaglandin biosynthesis enzyme complex in G. vermiculophylla; this species, when grown in mariculture, can be used as a source of prostaglandins. 相似文献
872.
Grahn DA Cao VH Nguyen CM Liu MT Heller HC 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(9):2558-2569
Body core cooling via the palm of a hand increases work volume during resistive exercise. We asked: (a) "Is there a correlation between elevated core temperatures and fatigue onset during resistive exercise?" and (b) "Does palm cooling between sets of resistive exercise affect strength and work volume training responses?" Core temperature was manipulated by 30-45 minutes of fixed load and duration treadmill exercise in the heat with or without palm cooling. Work volume was then assessed by 4 sets of fixed load bench press exercises. Core temperatures were reduced and work volumes increased after palm cooling (Control: Tes = 39.0 ± 0.1° C, 36 ± 7 reps vs. Cooling: Tes = 38.4 ± 0.2° C, 42 ± 7 reps, mean ± SD, n = 8, p < 0.001). In separate experiments, the impact of palm cooling on work volume and strength training responses were assessed. The participants completed biweekly bench press or pull-up exercises for multiple successive weeks. Palm cooling was applied for 3 minutes between sets of exercise. Over 3 weeks of bench press training, palm cooling increased work volume by 40% (vs. 13% with no treatment; n = 8, p < 0.05). Over 6 weeks of pull-up training, palm cooling increased work volume by 144% in pull-up experienced subjects (vs. 5% over 2 weeks with no treatment; n = 7, p < 0.001) and by 80% in pull-up na?ve subjects (vs. 20% with no treatment; n = 11, p < 0.01). Strength (1 repetition maximum) increased 22% over 10 weeks of pyramid bench press training (4 weeks with no treatment followed by 6 weeks with palm cooling; n = 10, p < 0.001). These results verify previous observations about the effects of palm cooling on work volume, demonstrate a link between core temperature and fatigue onset during resistive exercise, and suggest a novel means for improving strength and work volume training responses. 相似文献
873.
Gruzdev A Nguyen M Kovarova M Koller BH 《Prostaglandins & other lipid mediators》2012,97(3-4):109-119
The ductus arteriosus (DA) is a fetal shunt that directs right ventricular outflow away from pulmonary circulation and into the aorta. Critical roles for prostaglandin E(2) (PGE(2)) and the EP4 receptor (EP4) have been established in maintaining both the patency of the vessel in utero and in its closure at birth. Here we have generated mice in which loss of EP4 expression is limited to either the smooth muscle (SMC) or endothelial cells and demonstrated that SMC, but not endothelial cell expression of EP4 is required for DA closure. The genome wide expression analysis of full term wild type and EP4(-/-) DA indicates that PGE(2)/EP4 signaling modulates expression of a number of unique pathways, including those involved in SMC proliferation, cell migration, and vascular tone. Together this supports a mechanism by which maturation and increased contractility of the vessel is coupled to the potent smooth muscle dilatory actions of PGE(2). 相似文献
874.
875.
Aditya Nath Jha Vipin Kumar Singh Namrata Kumari Ashish Singh Justin Antony Hoang van Tong Sakshi Singh Sudhanshu S. Pati Pradeep K. Patra Rajender Singh Nguyen L. Toan Le H. Song Amal Assaf Iara J. T. Messias–Reason Thirumalaisamy P. Velavan Lalji Singh Kumarasamy Thangaraj 《PloS one》2012,7(10)
Background
Interleukin 4 (IL-4) is an anti-inflammatory cytokine, which regulates balance between TH1 and TH2 immune response, immunoglobulin class switching and humoral immunity. Polymorphisms in this gene have been reported to affect the risk of infectious and autoimmune diseases.Methods
We have analyzed three regulatory IL-4 polymorphisms; -590C>T, -34C>T and 70 bp intron-3 VNTR, in 4216 individuals; including: (1) 430 ethnically matched case-control groups (173 severe malaria, 101 mild malaria and 156 asymptomatic); (2) 3452 individuals from 76 linguistically and geographically distinct endogamous populations of India, and (3) 334 individuals with different ancestry from outside India (84 Brazilian, 104 Syrian, and 146 Vietnamese).Results
The -590T, -34T and intron-3 VNTR R2 alleles were found to be associated with reduced malaria risk (P<0.001 for -590C>T and -34C>T, and P = 0.003 for VNTR). These three alleles were in strong LD (r2>0.75) and the TTR2 (-590T, -34T and intron-3 VNTR R2) haplotype appeared to be a susceptibility factor for malaria (P = 0.009, OR = 0.552, 95% CI = 0.356 –0.854). Allele and genotype frequencies differ significantly between caste, nomadic, tribe and ancestral tribal populations (ATP). The distribution of protective haplotype TTR2 was found to be significant (χ2 3 = 182.95, p-value <0.001), which is highest in ATP (40.5%); intermediate in tribes (33%); and lowest in caste (17.8%) and nomadic (21.6%).Conclusions
Our study suggests that the IL-4 polymorphisms regulate host susceptibility to malaria and disease progression. TTR2 haplotype, which gives protection against malaria, is high among ATPs. Since they inhabited in isolation and mainly practice hunter-gatherer lifestyles and exposed to various parasites, IL-4 TTR2 haplotype might be under positive selection. 相似文献876.
877.
Nguyen Tien Huy Nguyen Thanh Hong Thao Nguyen Anh Tuan Nguyen Tuan Khiem Christopher C. Moore Doan Thi Ngoc Diep Kenji Hirayama 《PloS one》2012,7(11)
Background and Purpose
Successful outcomes from bacterial meningitis require rapid antibiotic treatment; however, unnecessary treatment of viral meningitis may lead to increased toxicities and expense. Thus, improved diagnostics are required to maximize treatment and minimize side effects and cost. Thirteen clinical decision rules have been reported to identify bacterial from viral meningitis. However, few rules have been tested and compared in a single study, while several rules are yet to be tested by independent researchers or in pediatric populations. Thus, simultaneous test and comparison of these rules are required to enable clinicians to select an optimal diagnostic rule for bacterial meningitis in settings and populations similar to ours.Methods
A retrospective cross-sectional study was conducted at the Infectious Department of Pediatric Hospital Number 1, Ho Chi Minh City, Vietnam. The performance of the clinical rules was evaluated by area under a receiver operating characteristic curve (ROC-AUC) using the method of DeLong and McNemar test for specificity comparison.Results
Our study included 129 patients, of whom 80 had bacterial meningitis and 49 had presumed viral meningitis. Spanos''s rule had the highest AUC at 0.938 but was not significantly greater than other rules. No rule provided 100% sensitivity with a specificity higher than 50%. Based on our calculation of theoretical sensitivity and specificity, we suggest that a perfect rule requires at least four independent variables that posses both sensitivity and specificity higher than 85–90%.Conclusions
No clinical decision rules provided an acceptable specificity (>50%) with 100% sensitivity when applying our data set in children. More studies in Vietnam and developing countries are required to develop and/or validate clinical rules and more very good biomarkers are required to develop such a perfect rule. 相似文献878.
Jian Luo Gayathri Swaminath Sean P. Brown Jane Zhang Qi Guo Michael Chen Kathy Nguyen Thanhvien Tran Lynn Miao Paul J. Dransfield Marc Vimolratana Jonathan B. Houze Simon Wong Maria Toteva Bei Shan Frank Li Run Zhuang Daniel C.-H. Lin 《PloS one》2012,7(10)
Type 2 diabetes is characterized by impaired glucose homeostasis due to defects in insulin secretion, insulin resistance and the incretin response. GPR40 (FFAR1 or FFA1) is a G-protein-coupled receptor (GPCR), primarily expressed in insulin-producing pancreatic β-cells and incretin-producing enteroendocrine cells of the small intestine. Several GPR40 agonists, including AMG 837 and TAK-875, have been disclosed, but no GPR40 synthetic agonists have been reported that engage both the insulinogenic and incretinogenic axes. In this report we provide a molecular explanation and describe the discovery of a unique and potent class of GPR40 full agonists that engages the enteroinsular axis to promote dramatic improvement in glucose control in rodents. GPR40 full agonists AM-1638 and AM-6226 stimulate GLP-1 and GIP secretion from intestinal enteroendocrine cells and increase GSIS from pancreatic islets, leading to enhanced glucose control in the high fat fed, streptozotocin treated and NONcNZO10/LtJ mouse models of type 2 diabetes. The improvement in hyperglycemia by AM-1638 was reduced in the presence of the GLP-1 receptor antagonist Ex(9–39)NH2. 相似文献
879.
Abhinav Kumar Sabine M?cklinghoff Fumiaki Yumoto Lukasz Jaroszewski Carol L. Farr Anna Grzechnik Phuong Nguyen Christian X. Weichenberger Hsiu-Ju Chiu Heath E. Klock Marc-André Elsliger Ashley M. Deacon Adam Godzik Scott A. Lesley Bruce R. Conklin Robert J. Fletterick Ian A. Wilson 《PloS one》2012,7(9)
880.
TM Hammett DC Des Jarlais R Kling BT Kieu JM McNicholl P Wasinrapee JS McDougal W Liu Y Chen D Meng N Doan T Huu Nguyen Q Ngoc Hoang T Van Hoang 《PloS one》2012,7(8):e43141