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141.
142.
Nasereddine Hamadi Ahmed Mansour Memy H. Hassan Fatima Khalifi‐Touhami Osama Badary 《Journal of biochemical and molecular toxicology》2012,26(10):384-392
The objective of this study was to investigate the ameliorative property and potential mechanism of resveratrol (RVT) in a dose of 10 mg/kg for 15 consecutive days against liver injury in streptozotocin‐induced diabetic rats. Diabetic rats significantly (P < 0.05) exhibited liver injury manifested by increased aspartylaminotransferase, alanine aminotransferase, and bilirubin; disturbed liver weight to body weight; and confirmed by hematoxylin and eosin staining. Liver from diabetic rats exhibited significant increase in malondialdehyde level and significant decrease in reduced glutathione, glutathione‐S‐transferase, quinone reductase, catalase, and superoxide dismutase. Diabetic rats showed significant disturbance in serum lipid profile. Treatment with RVT significantly (P < 0.05) abrogated diabetes‐induced perturbation in these parameters and liver histology. These data suggest that RVT treatment is associated with promising hepatoprotective effect against diabetes‐induced liver damage via reduction of serum glucose level and oxidative damage and improving serum lipid profile. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:384–392, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21432 相似文献
143.
Alexey Tomilov Ahmed Bettaieb Kyoungmi Kim Sunil Sahdeo Natalia Tomilova Adam Lam Kevork Hagopian Michelle Connell Jennifer Fong Douglas Rowland Stephen Griffey Jon Ramsey Fawaz Haj Gino Cortopassi 《Aging cell》2014,13(6):1049-1058
Adipose tissue is an important metabolic organ that integrates a wide array of homeostatic processes and is crucial for whole‐body insulin sensitivity and energy metabolism. Brown adipose tissue (BAT) is a key thermogenic tissue with a well‐established role in energy expenditure. BAT dissipates energy and protects against both hypothermia and obesity. Thus, BAT stimulation therapy is a rational strategy for the looming pandemic of obesity, whose consequences and comorbidities have a huge impact on the aged. Shc‐deficient mice (ShcKO) were previously shown to be lean, insulin sensitive, and resistant to high‐fat diet and obesity. We investigated the contribution of BAT to this phenotype. Insulin‐dependent BAT glucose uptake was higher in ShcKO mice. Primary ShcKO BAT cells exhibited increased mitochondrial respiration; increased expression of several mitochondrial and lipid‐oxidative enzymes was observed in ShcKO BAT. Levels of brown fat‐specific markers of differentiation, UCP1, PRDM16, ELOVL3, and Cox8b, were higher in ShcKO BAT. In vitro, Shc knockdown in BAT cell line increased insulin sensitivity and metabolic activity. In vivo, pharmacological stimulation of ShcKO BAT resulted in higher energy expenditure. Conversely, pharmacological inhibition of BAT abolished the improved metabolic parameters, that is the increased insulin sensitivity and glucose tolerance of ShcKO mice. Similarly, in vitro Shc knockdown in BAT cell lines increased their expression of UCP1 and metabolic activity. These data suggest increased BAT activity significantly contributes to the improved metabolic phenotype of ShcKO mice. 相似文献
144.
Ahmed Attia Younes Hachana Helmi Chaabène Abdelmajid Gaddour Zied Neji Roy J. Shephard Mohamed Souhaiel Chelly 《PloS one》2014,9(12)
The intent of this study was to evaluate relative and absolute reliability of the 20-s anaerobic test (WAnT20) versus the WAnT30 and to verify how far the various indices of the 30-s Wingate anaerobic test (WAnT30) could be predicted from the WAnT20 data in male athletes. The participants were Exercise Science majors (age: 21.5±1.6 yrs, stature: 0.183±0.08 m, body mass: 81.2±10.9 kg) who participated regularly in team sports. In Phase I, 41 participants performed duplicate WAnT20 and WAnT30 tests to assess reliability. In Phase II, 31 participants performed one trial each of the WAnT20 and WAnT30 to determine the ability of the WAnT20 to predict components of the WAnT30. In Phase III, 31 participants were used to cross-validate the prediction equations developed in Phase II. Respective intra-class correlation coefficients (ICC) for peak power output (PPO) (ICC = 0.98 and 0.95) and mean power output (MPO) (ICC 0.98 and 0.90) did not differ significantly between WAnT20 and WAnT30. ICCs for minimal power output (POmin) and fatigue index (FI) were poor for both tests (range 0.53 to 0.76). Standard errors of the means (SEM) for PPO and MPO were less than their smallest worthwhile changes (SWC) in both tests; however, POmin and FI values were “marginal,” with SEM values greater than their respective SWCs for both tests values. Stepwise regression analysis showed that MPO had the highest coefficient of predictability (R = 0.97), with POmin and FI considerable lower (R = 0.71 and 0.41 respectively). Cross-validation showed insignificant bias with limits of agreement of 0.99±1.04, 6.5±92.7 W, and 1.6±9.8% between measured and predicted MPO, POmin, and FI, respectively. WAnT20 offers a reliable and valid test of leg anaerobic power in male athletes and could replace the classic WAnT30. 相似文献
145.
Chimeric yellow fever/dengue virus as a candidate dengue vaccine: quantitation of the dengue virus-specific CD8 T-cell response 总被引:2,自引:0,他引:2 下载免费PDF全文
We have constructed a chimeric yellow fever/dengue (YF/DEN) virus, which expresses the premembrane (prM) and envelope (E) genes from DEN type 2 (DEN-2) virus in a YF virus (YFV-17D) genetic background. Immunization of BALB/c mice with this chimeric virus induced a CD8 T-cell response specific for the DEN-2 virus prM and E proteins. This response protected YF/DEN virus-immunized mice against lethal dengue encephalitis. Control mice immunized with the parental YFV-17D were not protected against DEN-2 virus challenge, indicating that protection was mediated by the DEN-2 virus prM- and E-specific immune responses. YF/DEN vaccine-primed CD8 T cells expanded and were efficiently recruited into the central nervous systems of DEN-2 virus challenged mice. At 5 days after challenge, 3 to 4% of CD8 T cells in the spleen were specific for the prM and E proteins, and 34% of CD8 T cells in the central nervous system recognized these proteins. Depletion of either CD4 or CD8 T cells, or both, strongly reduced the protective efficacy of the YF/DEN virus, stressing the key role of the antiviral T-cell response. 相似文献
146.
Mohammed Asif Ahmed Abdulrahman S. Al-Khalifa Doha M. Al-Nouri Mohamed Fekry Serag El-din 《Saudi Journal of Biological Sciences》2021,28(1):27-34
Nutritional risk in children is associated with food safety. This is the first study to identify the food type consumed by 6–17-year-old school-going children in Saudi Arabia. Eight permitted artificial food color additives, including Tartrazine (E102), Sunset Yellow (E110), Carmoisine (E122), Allura Red (E129), Indigo Carmine (E132), Brilliant Blue (E133), Fast Green (E143), and Black PN (E151), and two non-permitted ones, Erythrosine (E127) and Red 2G (E128), were determined using 24-h dietary recall questionnaires. Artificial color additives in 839 food products were divided into nine categories, including biscuits, cakes, chocolates, chips, ice cream, juices and drinks, candy, jelly, and chewing gum, are determined using high performance liquid chromatography and diode array detector. The results indicated a high intake of juices and drinks, ice cream, and cakes, but low consumption of chewing gum among school-going children. Among the permitted artificial food color additives, Brilliant Blue (E133) (54.1%) and Tartrazine (E102) (42.3%) were the most commonly used. Sunset Yellow (E110) in one chocolate sample, Tartrazine (E102) and Sunset Yellow (E110) in one and two juice and drink samples, respectively, and Brilliant Blue (E133) in two candy samples exceeded the permitted level. Therefore, further investigations are needed to provide insights into the possible adverse health effects of high intake of these additives in artificial food coloring on the test population are warranted. 相似文献
147.
Elizabeth L. Turner Siham Sikander Omer Bangash Ahmed Zaidi Lisa Bates John Gallis Nima Ganga Karen O’Donnell Atif Rahman Joanna Maselko 《Trials》2016,17(1)
BackgroundThe negative effects of perinatal depression on the mother and child start early and persist throughout the lifecourse (Lancet 369(9556):145–57, 2007; Am J Psychiatry 159(1):43-7, 2002; Arch Dis Child 77(2):99–101, 1997; J Pak Med Assoc 60(4):329; J Psychosoma Res 49(3):207–16, 2000; Clin Child Fam Psychol Rev 14(1):1–27, 2011). Given that 10–35 % of children worldwide are exposed to perinatal depression in their first year of life (Int Rev Psychiatry 8(1):37–54, 1996), mitigating this intergenerational risk is a global public health priority (Perspect Public Health 129(5):221–7, 2009; Trop Med Int Health 13(4):579–83, 2008; Br Med Bull 101(1):57–79, 2012). However, it is not clear whether intervention with depressed women can have long-term benefits for the mother and/or her child. We describe a study of the effectiveness of a peer-delivered depression intervention delivered through 36 postnatal months, the Thinking Healthy Program Peer-delivered PLUS (THPP+) for women and their children in rural Pakistan.Methods/designThe THPP+ study aims are: (1) to evaluate the effects of an extended 36-month perinatal depression intervention on maternal and index child outcomes using a cluster randomized controlled trial (c-RCT) and (2) to determine whether outcomes among index children of perinatally depressed women in the intervention arm converge with those of index children born to perinatally nondepressed women. The trial is designed to recruit 560 pregnant women who screened positive for perinatal depression (PHQ-9 score ≥10) from 40 village clusters, of which 20 receive the THPP+ intervention. An additional reference group consists of 560 perinatally nondepressed women from the same 40 clusters as the THPP+ trial. The women in the nondepressed group are not targeted to receive the THPP+ intervention; but, by recruiting pregnant women from both intervention and control clusters, we are able to evaluate any carryover effects of the THPP+ intervention on the women and their children. Perinatally depressed women in the THPP+ intervention arm receive bimonthly group-based sessions. Primary outcomes are 3-year maternal depression and 3-year child development indicators. Analyses are intention-to-treat and account for the clustered design.DiscussionThis trial, together with the reference group, has the potential to further our understanding of the early developmental lifecourse of children of both perinatally depressed and perinatally nondepressed women in rural Pakistan and to determine whether intervening with women’s depression in the perinatal period can mitigate the negative effects of maternal depression on 36-month child development.
Trial registration
THPP-P ClinicalTrials.gov Identifier: (registered on 9 April 2014).THPP+ ClinicalTrials.gov Identifier: NCT02111915 (registered on 21 January 2016).Sponsor: Human Development Research Foundation (HDRF). NCT02658994Electronic supplementary material
The online version of this article (doi:10.1186/s13063-016-1530-y) contains supplementary material, which is available to authorized users. 相似文献148.
Background
Rosetting is a Plasmodium falciparum virulence factor implicated in the pathogenesis of life-threatening malaria. Rosetting occurs when parasite–derived P. falciparum Erythrocyte Membrane Protein One (PfEMP1) on the surface of infected erythrocytes binds to human receptors on uninfected erythrocytes. PfEMP1 is a possible target for a vaccine to induce antibodies to inhibit rosetting and prevent severe malaria.Methodology/Findings
We examined the vaccine potential of the six extracellular domains of a rosette-mediating PfEMP1 variant (ITvar9/R29var1 from the R29 parasite strain) by immunizing rabbits with recombinant proteins expressed in E. coli. Antibodies raised to each domain were tested for surface fluorescence with live infected erythrocytes, rosette inhibition and phagocytosis-induction. Antibodies to all PfEMP1 domains recognized the surface of live infected erythrocytes down to low concentrations (0.02–1.56 µg/ml of total IgG). Antibodies to all PfEMP1 domains except for the second Duffy-Binding-Like region inhibited rosetting (50% inhibitory concentration 0.04–4 µg/ml) and were able to opsonize and induce phagocytosis of infected erythrocytes at low concentrations (1.56–6.25 µg/ml). Antibodies to the N-terminal region (NTS-DBL1α) were the most effective in all assays. All antibodies were specific for the R29 parasite strain, and showed no functional activity against five other rosetting strains.Conclusions/Significance
These results are encouraging for vaccine development as they show that potent antibodies can be generated to recombinant PfEMP1 domains that will inhibit rosetting and induce phagocytosis of infected erythrocytes. However, further work is needed on rosetting mechanisms and cross-reactivity in field isolates to define a set of PfEMP1 variants that could induce functional antibodies against a broad range of P. falciparum rosetting parasites. 相似文献149.
Ahmed Aboul-Fotouh Mourad Seikou Nakamura Tsubasa Ueno Takahiro Minami Takanari Yagi Haruka Yasue Ryoko Komatsu Masayuki Yoshikawa Ashraf Mohamed Taye Mohamed Ahmed El-Moselhy Mohamed Montaser Khalifa Hisashi Matsuda 《Bioorganic & medicinal chemistry letters》2013,23(17):4813-4816
In a previous study, retrofractamide A from the fruit of Piper chaba was shown to promote adipogenesis in 3T3-L1 cells. In the present study, retrofractamide A and its derivatives were synthesized, and their adipogenetic effects in 3T3-L1 cells were examined. Among the tested compounds, an amide composed of 9-(3′,4′-methylenedioxyphenyl)-nona-2E,4E,8E-trienoic acid and an n-butyl or n-pentyl amine showed strongest activity. Moreover, the amide with the n-pentyl amine moiety significantly increased the uptake of 2-deoxyglucose into the cells, and also increased the mRNA levels of adiponectin, peroxisome proliferator-activated receptor γ2 (PPARγ2), glucose transporter 4 (GLUT4), fatty acid-binding protein (aP2), and CCAAT/enhancer-binding protein (C/EBP) α and β in a similar manner as the PPARγ agonist troglitazone, although it had less agonistic activity against PPARγ. 相似文献
150.