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991.
Most people are aware that outdoor air pollution can damage their health, but many do not know that indoor air pollution can also exhibit significant negative health effects. Fungi parasitizing in air conditioning and ventilation systems can be one of indoor air pollution sources. Aflatoxin produced by Aspergillus flavus (A. flavus) became a central focus of indoor air pollution, especially in farmer markets. Therefore we developed an early warning system, Health Risk Assessment System, to estimate the growth rate of A. flavus, predict the amount of aflatoxin and provide early warning information. Firstly, the growth of A. flavus and the production of aflatoxin under different conditions were widely obtained through a comprehensive literature review. Secondly, three mathematical models were established to predict the A. flavus colony growth rate, lag phase duration and aflatoxin content, as functions of temperature and water activity based on present studies. Finally, all the results were evaluated by the user-supplied data using PHP programming language. We utilized the web page to show the results and display warning information. The JpGraph library was used to create a dynamic line chart, refreshing the warning information dynamically in real-time. The HARS provides accurate information for early warning purposes to let us take timely steps to protect ourselves. 相似文献
992.
Hongbo Zhao Zhiyong Ji Deji Tang Cong Yan Wenyang Zhao Cheng Gao 《Molecular biology reports》2013,40(2):819-827
Early brain injury (EBI) occurred after aneurismal subarachnoid hemorrhage (SAH) strongly determined the patients’ prognosis. Autophagy was activated in neurons in the acute phase after SAH, while its role in EBI has not been examined. This study was designed to explore the effects of autophagy on EBI post-SAH in rats. A modified endovascular perforating SAH model was established under monitoring of intracranial pressure. Extent of autophagy was regulated by injecting autophagy-regulating drugs (3-methyladenine, wortmannin and rapamycin) 30 min pre-SAH intraventricularly. Simvastatin (20 mg/kg) was prophylactically orally given 14 days before SAH induction. Mortality, neurological scores, brain water content and blood–brain barrier (BBB) permeability were evaluated at 24 h post-SAH. Microtubule-associated protein light chain-3 (LC3 II/I) and beclin-1 were detected for monitoring of autophagy flux. Terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling, expression of cleaved caspase-3 and cytoplasmic histone-associated DNA fragments were used to detect apoptosis. The results showed that mortality was reduced in rapamycin and simvastatin treated animals. When autophagy was inhibited by 3-methyladenine and wortmannin, the neurological scores were decreased, brain water content and BBB permeability were further aggravated and neuronal apoptosis was increased when compared with the SAH animals. Autophagy was further activated by rapamycin and simvastatin, and apoptosis was inhibited and EBI was ameliorated. The present results indicated that activation of autophagy decreased neuronal apoptosis and ameliorated EBI after SAH. Aiming at autophagy may be a potential effective target for preventing EBI after SAH. 相似文献
993.
Angiotensinogen, one of the most important proteins in the renin–angiotensin system, plays a key role in the progress of coronary heart disease and myocardial infarction (MI). Many studies have investigated the association between angiotensinogen gene M235T polymorphism and MI risk, but the results were inconsistent. We performed a meta-analysis of 22 studies on M235T polymorphism and MI risk published before November 2012. This meta-analysis included a total of 4,606 MI cases and 4,918 controls. Overall, the per-allele odds ratio (OR) of the 235T variant for total MI risk was 1.04 (95 % CI 0.92–1.17). When a recessive model was evaluated, the OR was 1.06 (95 % CI 0.96–1.17) and under a dominant model, the OR was 0.96 (95 % CI 0.82–1.11). Under pairwise comparisons, non-significant associations were found between M235T polymorphism and MI risk (MT vs. MM, OR, 0.96, 95 % CI 0.87–1.06; TT vs. MM, OR, 1.03, 95 % CI 0.83–1.28). Subgroup analyses in the different ethnic groups and different control sources were performed and no significant association was found also. Based on the available evidence, no association between M235T polymorphism and MI risk was observed, even in the sub-analysis concerning different races and control sources. The direction of further research should focus not only on the simple relationship of M235T polymorphism and MI risk, but also on gene–gene and gene-environment interaction. 相似文献
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Yang Zhou Lu Gao Haifeng Shi Hengchuan Xia Li Gao Chaoqun Lian Liang Chen Qin Yao Keping Chen Xiaoyong Liu 《Genomics》2013,101(4):256-262
To investigate the molecular mechanism of silkworm resistance to BmNPV infection, we constructed a near-isogenic line (BC8) with BmNPV resistance using highly resistant (NB) and highly susceptible parental strains (306). We investigated variations in the gene expression in the midguts of BmNPV-infected BC8 and 306 at 12 h pi using the microarray. 92 differentially expressed genes were identified. Real-time qPCR analysis confirmed that 10 genes were significantly up-regulated or down-regulated in the midguts of BC8 and NB compared to 306. To our knowledge, we first defined the role of the amino acid transporter and 26S proteasome in insect antiviral. However, serine protease was not completely consistent with data of reported previously in insect antiviral. The role of the 5 genes (Bm123, Bm122, COP β′, aquaporin, glycoside hydrolases) was also demonstrated in insect antiviral. Our results provided new insights into the molecular mechanism of the Bombyx mori immune response against BmNPV infection. 相似文献
1000.
A new specimen of Philydrosaurus proseilus from the Early Cretaceous Chiufotang (Jiufotang) Formation preserves the first complete palate of a monjurosuchid choristodere. As in other choristoderes, the palate of Philydrosaurus is akinetic, extended by a broad contact between the vomer and maxilla, and equipped with multiple batteries of palatal teeth. This specimen provides phylogenetically significant information and clarifies the distribution of many apomorphies within Choristodera. Philydrosaurus is primitive relative to the Neochoristodera in that it exhibits only a moderate degree of posterior displacement of the choanae and retains a relatively large interpterygoid vacuity. However, Philydrosaurus also exhibits several derived features previously considered diagnostic of the Neochoristodera, including establishment of a long midline contact of the pterygoids and development of a distinct nasopalatal trough extending from the choana. The choristodere palate exhibits significant modification of the primitive diapsid condition, including elongation of the vomers, establishment of a vomer–maxilla contact, posterior displacement of the choanae, development of the nasopalatal trough, and reduction of the interpterygoid vacuity. 相似文献