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991.
The identification of true causal loci to unravel the statistical evidence of genotype-phenotype correlations and the biological
relevance of selected single-nucleotide polymorphisms (SNPs) is a challenging issue in genome-wide association studies (GWAS).
Here, we introduced a novel method for the prioritization of SNPs based on p-values from GWAS. The method uses functional evidence from populations, including phenotype-associated gene expressions. Based on
the concept of genetic interactions, such as perturbation of gene expression by genetic variation, phenotype and gene expression
related SNPs were prioritized by adjusting the p-values of SNPs. We applied our method to GWAS data related to drug-induced cytotoxicity. Then, we prioritized loci that potentially
play a role in druginduced cytotoxicity. By generating an interaction model, our approach allowed us not only to identify
causal loci, but also to find intermediate nodes that regulate the flow of information among causal loci, perturbed gene expression,
and resulting phenotypic variation. 相似文献
992.
993.
Xiao F Gao W Wang X Chen T 《Apoptosis : an international journal on programmed cell death》2012,17(6):600-611
Although caspases have been demonstrated to be involved in artemisinin (ARTE)-induced apoptosis, their exact functions are
not well understood. The aim of this report is to explore the roles of caspase-8, -9 and -3 during ARTE-induced apoptosis
in human lung adenocarcinoma (ASTC-a-1) cells. ARTE treatment induces a rapid generation of reactive oxygen species (ROS),
and ROS-dependent apoptosis as well as the activation of caspase-8, -9 and -3 via time- and dose-dependent fashion. Of upmost
importance, inhibition of caspase-8 or -9, but not caspase-3, almost completely blocks the ARTE-induced not only activation
of the caspase-8, -9 and -3 but also apoptosis. In addition, the apoptotic process triggered by ARTE does not involve the
Bid cleavage, tBid translocation, significant loss of mitochondrial membrane potential and cytochrome c release from mitochondria.
Moreover, silencing Bax/Bak does not prevent the ATRE-induced cell death as well as the activation of caspase-8, -9 and -3.
Collectively, our data firstly demonstrate that ARTE triggers a ROS-mediated positive feedback amplification activation loop
between caspase-8 and -9 independent of mitochondria, which dominantly mediated the ARTE-induced apoptosis via a caspase-3-independent
apoptotic pathway in ASTC-a-1 cells. Our findings imply a potential to develop new derivatives from artemisinin to effectively
initiate the amplification activation loop of caspases. 相似文献
994.
Gerald Busch 《Bioenergy Research》2012,5(3):584-605
Based on regional stakeholder preferences and planning guidelines as allocation criteria for SRC, this study aims at providing a transparent approach to evaluate multiple environmental effects and the regional significance of SRC systems. Using the example of two poplar SRC-systems (4-year rotation, 9-year rotation) the potential effects on ground water supply, wind erosion, and biodiversity aspects are evaluated in comparison to arable land for two selected municipalities in the district of Uelzen, Germany. Building on fuzzy membership functions and simple fuzzy-logic rules, the qualitative multi-criteria assessment is transparent and easily to adapt. This approach is transferable to other regions and spatial levels, since it derives from commonly available data and scientific evidence. Results show that implementation of SRC could provide multiple beneficial environmental effects, especially in areas with low landscape heterogeneity. The tools provided allow for a multi-criteria evaluation of environmental effects, and reveal the sensitivity to distinct allocation patterns. Physiographical conditions of the study area implicate a preference for mini-SRC systems. This is supported by smaller decline of annual deep percolation water compared to maxi-SRC. On average, decline in groundwater recharge of mini-SRC (92mm a−1) is comparable to irrigated arable land (80mm a−1), which is common practice in the study area. Currently, the utilization of beneficial environmental SRC effects is quite limited, since only 3 % of arable land is suitable for SRC implementation regarding farmers’ preferences for SRC allocation. Allocation preferences could however change substantially with increasing incentives for SRC, e.g., due to regional bioenergy schemes or “Greening” initiatives within the European Common Agricultural Policy, which is to be reformed by 2013. 相似文献
995.
Zhu W Frost EE Begum F Vora P Au K Gong Y MacNeil B Pillai P Namaka M 《Journal of cellular and molecular medicine》2012,16(8):1856-1865
Multiple sclerosis (MS) is characterized by focal destruction of the white matter of the brain and spinal cord. The exact mechanisms underlying the pathophysiology of the disease are unknown. Many studies have shown that MS is predominantly an autoimmune disease with an inflammatory phase followed by a demyelinating phase. Recent studies alongside current treatment strategies, including glatiramer acetate, have revealed a potential role for brain-derived neurotrophic factor (BDNF) in MS. However, the exact role of BDNF is not fully understood. We used the experimental autoimmune encephalomyelitis (EAE) model of MS in adolescent female Lewis rats to identify the role of BDNF in disease progression. Dorsal root ganglia (DRG) and spinal cords were harvested for protein and gene expression analysis every 3 days post-disease induction (pdi) up to 15 days. We show significant increases in BDNF protein and gene expression in the DRG of EAE animals at 12 dpi, which correlates with peak neurological disability. BDNF protein expression in the spinal cord was significantly increased at 12 dpi, and maintained at 15 dpi. However, there was no significant change in mRNA levels. We show evidence for the anterograde transport of BDNF protein from the DRG to the dorsal horn of the spinal cord via the dorsal roots. Increased levels of BDNF within the DRG and spinal cord in EAE may facilitate myelin repair and neuroprotection in the CNS. The anterograde transport of DRG-derived BDNF to the spinal cord may have potential implications in facilitating central myelin repair and neuroprotection. 相似文献
996.
Shun-ichiro Takano Keiji Takasu Ryoko T. Ichiki Satoshi Nakamura 《Applied Entomology and Zoology》2012,47(3):173-180
The coconut hispine beetle, Brontispa longissima (Gestro), supposedly originated from Papua New Guinea and Indonesia but has recently invaded Southeast and East Asian countries where it has been causing serious damage to Cocos nucifera L. This insect also occurs on the Southwest Islands off Kyushu Island in Japan. To evaluate the potential northward range expansion of this insect in Japan, we investigated its cold tolerance at 0, 5, and 10 °C (egg, larva, pupa, and adult), 13 °C (adult), and 15 °C (egg and hatched larva). At 15 °C, few eggs hatched, and the larvae that hatched died within a few days of hatching. At 13 °C, Ltime95 was estimated to be 23 days for adults, with the most cold-tolerant developmental stage at 10 °C. At all developmental stages, Ltime95 of B. longissima was estimated to be 19 days at 10 °C, 8 days at 5 °C, and 5 days at 0 °C, suggesting the cold tolerance of this beetle is very low. Considering average daily temperatures, it is unlikely that B. longissima can establish itself north of Amami-Oshima Island, located in the far south off the main island of Japan. 相似文献
997.
Yuki Nakamura Fumiko Yukuhiro Masaya Matsumura Hiroaki Noda 《Applied Entomology and Zoology》2012,47(3):273-283
Cytoplasmic incompatibility (CI) is a reproductive phenotype induced by bacterial endosymbionts in arthropods. Measured as a reduction in egg hatchability resulting from the crossing of uninfected females with bacteria-infected males, CI increases the frequency of bacteria-infected hosts by restricting the fertilization opportunities of uninfected hosts in populations. Wolbachia, a type of alpha-proteobacteria, is well known as a CI inducer in a wide range of arthropod species, while Cardinium, a member of the phylum Bacteroidetes, is known to cause CI in one wasp and three spider mite species. In this study, dual infection with Cardinium and Wolbachia induced strong CI in a single host, Sogatella furcifera (Horváth), a planthopper species that is naturally infected with both bacteria. Specifically, infection with Cardinium alone was found to cause a 76 % reduction in egg development, and dual infection with Cardinium and Wolbachia a 96 % reduction, indicating that Cardinium induces CI and the dual infection raises the CI level. This study was the first to document reproductive alteration by Cardinium in a diploid host species. 相似文献
998.
Il’ja Krno Ferdinand Šporka Joanna Galas Ladislav Hamerlík Zuzana Zaťovičová Peter Bitušík 《Biologia》2006,61(18):S147-S166
Littoral benthic macroinvertebrates of 45 mountain lakes in the Tatra Mountains were sampled using a semi-quantitative method in September 2000. A total of 32,852 specimens were identified to 93 taxa belonging to 14 higher taxonomic groups. Multivariate statistics (CCA, RDA) and nine biotic metrics (AQEM/STAR) were used to explain relationships between macroinvertebrate assemblages and environmental variables. Up to 57% of the ecological position of littoral macroinvertebrate assemblages were explained by variance of environmental variables divided into chemical, trophic, physical, catchment and location. Five types of Tatra lakes were recognized using CCA: A — strongly acidified lakes (small catchment, low pH, high concentration of TP, DOC, highest amount of POM in littoral); B — alpine acidified lakes (low amount of POM, low values of biotic metrics); C — alpine non-acidified lakes (high value of diversity index, predominance of Diptera); D — subalpine acidified lakes (high values of biotic metrics: number of families, proportion of crenal and rhithral taxa/total taxa); E — subalpine non-acidified lakes (high values of biotic metrics: number of families, number of genera, BMWP score, number of taxa and abundance of EPT taxa). RDA was used to design five levels of macroinvertebrate taxa acidification tolerance. The Tatra Acidification Index (TAI) was established to assess the acidification status of the lakes in the Tatra Mts. 相似文献
999.
Background
Biering-Sørenson (1984) found that individuals with less lumbar extensor muscle endurance had an increased occurrence of first episode low back pain. As a result, back endurance tests have been recommended for inclusion in health assessment protocols. However, different studies have reported markedly different values for endurance times, leading some researchers to believe that the back is receiving support from the biceps femoris and gluteus maximus. Therefore, this study was designed to examine the haemodynamic and neuromuscular activity of the erector spinae, biceps femoris, and gluteus maximus musculature during the Biering-Sørenson Muscular Endurance Test (BSME).Methods
Seventeen healthy individuals and 46 individuals with chronic low back pain performed the Biering-Sørenson Muscular Endurance Test while surface electromyography was used to quantify neuromuscular activity. Disposable silver-silver-chloride electrodes were placed in a bipolar arrangement over the right or left biceps femoris, gluteus maximus, and the lumbosacral paraspinal muscles at the level of L3. Near Infrared Spectroscopy was used simultaneously to measure tissue oxygenation and blood volume changes of the erector spinae and biceps femoris.Results
The healthy group displayed a significantly longer time to fatigue (Healthy: 168.5s, LBP: 111.1s; p ≤ 0.05). Significant differences were shown in the median frequency slope of the erector spinae between the two groups at 90–100% of the time to fatigue while no significant differences were noted in the haemodynamic data for the two groups.Conclusion
Although the BSME has been recognized as a test for back endurance, individuals with chronic LBP appear to incorporate a strategy that may help support the back musculature by utilizing the biceps femoris and gluteus maximus to a greater degree than their healthy counterparts.1000.