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991.
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Ellen?M?Unterwald Michelle?E?Page Timothy?B?Brown Jonathan?S?Miller Marta?Ruiz Karen?A?Pescatore Baoji?Xu Louis?French?Reichardt Joel?Beverley Bin?Tang Heinz?Steiner Elizabeth?A?Thomas Michelle?E?EhrlichEmail author 《Molecular neurodegeneration》2013,8(1):47
Background
The high affinity tyrosine kinase receptor, TrkB, is the primary receptor for brain derived neurotrophic factor (BDNF) and plays an important role in development, maintenance and plasticity of the striatal output medium size spiny neuron. The striatal BDNF/TrkB system is thereby implicated in many physiologic and pathophysiologic processes, the latter including mood disorders, addiction, and Huntington’s disease. We crossed a mouse harboring a transgene directing cre-recombinase expression primarily to postnatal, dorsal striatal medium spiny neurons, to a mouse containing a floxed TrkB allele (fB) mouse designed for deletion of TrkB to determine its role in the adult striatum.Results
We found that there were sexually dimorphic alterations in behaviors in response to stressful situations and drugs of abuse. Significant sex and/or genotype differences were found in the forced swim test of depression-like behaviors, anxiety-like behaviors on the elevated plus maze, and cocaine conditioned reward. Microarray analysis of dorsal striatum revealed significant dysregulation in individual and groups of genes that may contribute to the observed behavioral responses and in some cases, represent previously unidentified downstream targets of TrkB.Conclusions
The data point to a set of behaviors and changes in gene expression following postnatal deletion of TrkB in the dorsal striatum distinct from those in other brain regions.995.
996.
The Genetic and Molecular Basis of Plant Resistance to Pathogens 总被引:1,自引:0,他引:1
Plant pathogens have evolved numerous strategies to obtain nutritive materials from their host,and plants in turn have evolved the preformed physical and chemical barriers as well as sophisticated two-tiered immune system to combat pathogen attacks.Genetically, plant resistance to pathogens can be divided into qualitative and quantitative disease resistance,conditioned by major gene(s) and multiple genes with minor effects,respectively.Qualitative disease resistance has been mostly detected in plant defense against biotrophic pathogens,whereas quantitative disease resistance is involved in defense response to all plant pathogens,from biotrophs,hemibiotrophs to necrotrophs.Plant resistance is achieved through interception of pathogen-derived effectors and elicitation of defense response.In recent years,great progress has been made related to the molecular basis underlying host-pathogen interactions.In this review,we would like to provide an update on genetic and molecular aspects of plant resistance to pathogens. 相似文献
997.
To assess the biological safety of Fe3O4 nanoparticles (NPs), the oxidative-damage effect of these NPs was studied. Twenty-five Kunming mice were exposed to Fe3O4 NPs by intraperitoneai injection daily for 1 week at doses of 0, 10, 20, and 40 mg.kg1. Five Kunming mice were also injected with 40 mg.kg 1 ordinary Fe3O4 particles under the same physiological conditions. Biomarkers of reactive oxygen species (ROS), glutathione (GSH), and malondialdehyde (MDA) in the hepatic and brain tissues were detected. Results showed that no significant difference in oxidative damage existed at concentrations lower than 10 mg.kg i for NPs compared with the control group. Fe3O4 NP concentration had obvious dose-effect relationships (P〈 0.05 or P 〈 0.01) with ROS level, GSH content, and MDA content in mouse hepatic and brain tissues at〉20 mg.kg 1 concentrations. To some extent, ordinary Fe3O4 particles with 40mg.kg -1 concentration also affected hepatic and brain tissues in mice. The biological effect was similar to Fe3O4 NPs at 10 mg. kg-1 concentration. Thus, Fe3O4 NPs had significant damage effects on the antioxidant defense system in the hepatic and brain tissues of mice, whereas ordinary Fe3O4 had less influence than Fe3O4 NPs at the same concentration. 相似文献
998.
Objective
To investigate the levels of primary health care services for children and their changes in Zhejiang Province, China from 1998 to 2011.Methods
The data were drawn from Zhejiang maternal and child health statistics collected under the supervision of the Health Bureau of Zhejiang Province. Primary health care coverage, hospital deliveries, low birth weight, postnatal visits, breastfeeding, underweight, early neonatal (<7 days) mortality, neonatal mortality, infant mortality and under-5 mortality were investigated.Results
The coverage rates for children under 3 years old and children under 7 years old increased in the last 14 years. The hospital delivery rate was high during the study period, and the overall difference narrowed. There was a significant difference (P<0.001) between the prevalence of low birth weight in 1998 (2.03%) and the prevalence in 2011 (2.71%). The increase in low birth weight was more significant in urban areas than in rural areas. The postnatal visit rate increased from 95.00% to 98.45% with a significant difference (P<0.001). The breastfeeding rate was the highest in 2004 at 74.79% and lowest in 2008 at 53.86%. The prevalence of underweight in children under 5 years old decreased from 1.63% to 0.65%, and the prevalence was higher in rural areas. The early neonatal, neonatal, infant and under-5 mortality rates decreased from 6.66‰, 8.67‰, 11.99‰ and 15.28‰ to 1.69‰, 2.36‰, 3.89‰ and 5.42‰, respectively (P<0.001). The mortality rates in rural areas were slightly higher than those in urban areas each year, and the mortality rates were lower in Ningbo, Wenzhou, and Jiaxing regions and higher in Quzhou and Lishui regions.Conclusion
Primary health care services for children in Zhejiang Province improved from 1998 to 2011. Continued high rates of low birth weight in urban areas and mortality in rural areas may be addressed with improvements in health awareness and medical technology. 相似文献999.
Porcine cytomegalovirus (PCMV) is an immunosuppressive virus that mainly inhibits the immune function of the macrophage and T-cell lymphatic systems, and has caused huge economic losses to the porcine breeding industry. Molecular epidemiological investigation of PCMV is important for prevention and treatment, and this study is the first such investigation in Sichuan Province, Southwest China. A PCMV positive infection rate of 84.4% (865/1025) confirmed that PCMV is widely distributed in Sichuan Province. A phylogenetic tree was constructed based on the PCMV glycoprotein B gene (gB) nucleotide and amino acid sequences from 24 novel Sichuan isolates and 18 other PCMV gB sequences from Genbank. PCMV does not appear to have evolved into different serotypes, and two distinct sequence groups were identified (A and B). However, whether PCMV from this region has evolved into different genotypes requires further research. Analysis of the amino acid sequences confirmed the conservation of gB, but amino acid substitutions in the major epitope region have caused antigenic drift, which may have altered the immunogenicity of PCMV. 相似文献
1000.
Wei Chen Wen Shu Min Wang Yongchun Hou Yinyin Xia Weiguo Xu Liqiong Bai Shaofa Nie Shiming Cheng Yihua Xu 《PloS one》2013,8(3)
The incidence of tuberculosis (TB) and its risk factors in China remains unclear. This study examined TB incidence and relative risk factors in rural areas of China. Participants (n = 177,529) were recruited in Xiangtan County (in the central area of China) and in Danyang County (in the eastern area of China) in 2009 and a followed-up study was conducted for one year. The incidence density of pulmonary TB and smear-positive TB were 91.6 (95% CI: 78.7, 106.0) per 100,000 person-year and 36.7 (95% CI: 33.1, 52.4) per 100,000 person-year respectively in Xiangtan, and 47.3 (95% CI: 38.2, 57.5) per 100,000 person-year and 22.7 (95% CI: 16.5, 30.8) per 100,000 person-year in Danyang. The medical history of TB was associated with TB, with the relative risk (RR) of 7.00 (95% CI: 2.76, 17.18) in Xiangtan and that of 31.08 (95% CI: 13.22, 73.10) in Danyang. The association between TB and per capita living space over median was found in Xiangtan, with the RR of 1.86 (95% CI: 1.15, 3.01). No association was found between TB and the insurance status, the contact history with TB, the history of diabetes, smoking, or per capita annual income. The host genetic susceptibility, and social factors such as education and income could be considered in future studies. 相似文献