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111.
The present study was designed to investigate ex vivo the protective mechanisms of heat-shock response against H2O2-induced oxidative stress in peripheral blood mononuclear cells (PBMCs) of rats. Twenty-four hours later, heat-shock treatment
was executed in vivo; rat PBMCs were collected and treated with H2O2. The accumulation of reactive oxygen species and the mitochondrial membrane potential were evaluated by intracellular fluorescent
dHE and JC-1 dye staining, respectively, and expression of HSP72 and cytochrome c was detected by Western blot analysis. Cellular apoptosis was assayed by TUNEL staining and double staining of Annexin V
and PI. The results showed that H2O2-induced oxidative stress leads to intracellular superoxide accumulation and collapse of the mitochondrial membrane potential
in rat PBMCs. Moreover, cellular apoptosis was detected after H2O2 treatment, and the release of mitochondrial cytochrome c from mitochondria to cytosol was significantly enhanced. Heat-shock pretreatment decreases the accumulation of intracellular
superoxide in PBMCs during H2O2-induced oxidative stress. Moreover, heat-shock treatment prevents the collapse of the mitochondrial membrane potential and
cytochrome c release from mitochondria during H2O2-induced oxidative stress. In conclusion, mitochondria are critical organelles of the protective effects of heat-shock treatment.
Cellular apoptosis during H2O2-induced oxidative stress is decreased by heat-shock treatment through a decrease in superoxide induction and preservation
of the mitochondrial membrane potential. 相似文献
112.
W. Si † X. Ni ‡ J. Gong H. Yu R. Tsao Y. Han J.R. Chambers 《Journal of applied microbiology》2009,106(1):213-220
Aims: To assess the potential of essential oils and structurally related synthetic food additives in inhibiting the growth of Clostridium perfringens for the control of necrotic enteritis in chickens.
Methods and Results: The antimicrobial activity of essential oils/compounds was measured by determining the inhibition of bacterial growth. Thirty-three of 66 oils/compounds exhibited ≥80% inhibition. Seven with the highest potency were further studied. The oils/compounds had MIC95 values between 167 and 425 μ g ml−1 . Most of them were tolerant to low pH (2·0) and exhibited minor or no inhibition of Lactobacillus isolates from the chicken intestine. When mixed with chicken ileal digesta, the oils/compounds retained their efficacy against C . perfringens , but had little effect on the total number of lactobacilli and anaerobic bacteria in the digesta.
Conclusions: Some essential oils/compounds demonstrated good potential in controlling C . perfringens .
Significance and Impact of the Study: This study has identified candidates of essential oils/compounds for in vivo studies for the control of necrotic enteritis in chickens. 相似文献
Methods and Results: The antimicrobial activity of essential oils/compounds was measured by determining the inhibition of bacterial growth. Thirty-three of 66 oils/compounds exhibited ≥80% inhibition. Seven with the highest potency were further studied. The oils/compounds had MIC
Conclusions: Some essential oils/compounds demonstrated good potential in controlling C . perfringens .
Significance and Impact of the Study: This study has identified candidates of essential oils/compounds for in vivo studies for the control of necrotic enteritis in chickens. 相似文献
113.
Maria Teresa Landi Nilanjan Chatterjee Lynn R. Goldin Melissa Rotunno Kevin Jacobs Meredith Yeager Qizhai Li Dario Consonni Sholom Wacholder Ryan Diver Jarmo Virtamo Zhaoming Wang Kimberly F. Doheny Cathy Laurie Rayjean Hung James D. McKay John McLaughlin Ming-Sound Tsao Yufei Wang Lars Vatten Egil Arnesen Christine Bouchard Tonu Vooder Kristian Välk Chu Chen Patrick Sulem Thorunn Rafnar Wiebke Sauter Heike Bickeböller Jenny Chang-Claude Kari Stefansson Christopher I. Amos Sharon A. Savage Margaret A. Tucker Neil E. Caporaso 《American journal of human genetics》2009,85(5):679-74
Three genetic loci for lung cancer risk have been identified by genome-wide association studies (GWAS), but inherited susceptibility to specific histologic types of lung cancer is not well established. We conducted a GWAS of lung cancer and its major histologic types, genotyping 515,922 single-nucleotide polymorphisms (SNPs) in 5739 lung cancer cases and 5848 controls from one population-based case-control study and three cohort studies. Results were combined with summary data from ten additional studies, for a total of 13,300 cases and 19,666 controls of European descent. Four studies also provided histology data for replication, resulting in 3333 adenocarcinomas (AD), 2589 squamous cell carcinomas (SQ), and 1418 small cell carcinomas (SC). In analyses by histology, rs2736100 (TERT), on chromosome 5p15.33, was associated with risk of adenocarcinoma (odds ratio [OR] = 1.23, 95% confidence interval [CI] = 1.13–1.33, p = 3.02 × 10−7), but not with other histologic types (OR = 1.01, p = 0.84 and OR = 1.00, p = 0.93 for SQ and SC, respectively). This finding was confirmed in each replication study and overall meta-analysis (OR = 1.24, 95% CI = 1.17–1.31, p = 3.74 × 10−14 for AD; OR = 0.99, p = 0.69 and OR = 0.97, p = 0.48 for SQ and SC, respectively). Other previously reported association signals on 15q25 and 6p21 were also refined, but no additional loci reached genome-wide significance. In conclusion, a lung cancer GWAS identified a distinct hereditary contribution to adenocarcinoma. 相似文献
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Maria A. Diuk‐Wasser Gwenaël Vourc'h Paul Cislo Anne Gatewood Hoen Forrest Melton Sarah A. Hamer Michelle Rowland Roberto Cortinas Graham J. Hickling Jean I. Tsao Alan G. Barbour Uriel Kitron Joseph Piesman Durland Fish 《Global Ecology and Biogeography》2010,19(4):504-514
Aim Ixodes scapularis is the most important vector of human tick‐borne pathogens in the United States, which include the agents of Lyme disease, human babesiosis and human anaplasmosis, among others. The density of host‐seeking I. scapularis nymphs is an important component of human risk for acquiring Borrelia burgdorferi, the aetiological agent of Lyme disease. In this study we used climate and field sampling data to generate a predictive map of the density of host‐seeking I. scapularis nymphs that can be used by the public, physicians and public health agencies to assist with the diagnosis and reporting of disease, and to better target disease prevention and control efforts. Location Eastern United States of America. Methods We sampled host‐seeking I. scapularis nymphs in 304 locations uniformly distributed east of the 100th meridian between 2004 and 2006. Between May and September, 1000 m2 were drag sampled three to six times per site. We developed a zero‐inflated negative binomial model to predict the density of host‐seeking I. scapularis nymphs based on altitude, interpolated weather station and remotely sensed data. Results Variables that had the strongest relationship with nymphal density were altitude, monthly mean vapour pressure deficit and spatial autocorrelation. Forest fragmentation and soil texture were not predictive. The best‐fit model identified two main foci – the north‐east and upper Midwest – and predicted the presence and absence of I. scapularis nymphs with 82% accuracy, with 89% sensitivity and 82% specificity. Areas of concordance and discordance with previous studies were discussed. Areas with high predicted but low observed densities of host‐seeking nymphs were identified as potential expansion fronts. Main conclusions This model is unique in its extensive and unbiased field sampling effort, allowing for an accurate delineation of the density of host‐seeking I. scapularis nymphs, an important component of human risk of infection for B. burgdorferi and other I. scapularis‐borne pathogens. 相似文献
117.
Elliott JM Carling RW Chambers M Chicchi GG Hutson PH Jones AB MacLeod A Marwood R Meneses-Lorente G Mezzogori E Murray F Rigby M Royo I Russell MG Sohal B Tsao KL Williams B 《Bioorganic & medicinal chemistry letters》2006,16(22):5748-5751
A new class of potent NK3R antagonists based on the N',2-diphenylquinoline-4-carbohydrazide core is described. In an ex vivo assay in gerbil, the lead compound 2g occupies receptors within the CNS following oral dosing (Occ(90) 30 mg/kg po; plasma Occ(90) 0.95 microM) and has good selectivity and promising PK properties. 相似文献
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