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161.
Nostoc punctiforme is an oxygenic photoautotrophic cyanobacterium with multiple developmental states, which can form nitrogen-fixing symbioses with a variety of terrestrial plants. 3D LC/MS/MS shotgun peptide sequencing was used to analyze the proteome when N. punctiforme is grown in continuous moderate light with ammonia as the nitrogen source. The soluble proteome includes 1575 proteins, 50% of which can be assigned to core metabolic and transport functions. Another 39% are assigned to proteins with no known function, a substantially higher fraction than in the Escherichia coli proteome. Many expressed proteins protect against oxidative and light stress. Seventy-one sensor histidine kinases, response regulators, and serine/threonine kinases, individually and as hybrid, multidomain proteins, were identified, reflecting a substantial capacity to sense and respond to environmental change. Proteins encoded by each of the five N. punctiforme plasmids were identified, as were 10 transposases, reflecting the plasticity of the N. punctiforme genome. This core proteome sets the stage for comparison with that of other developmental states.  相似文献   
162.
Zinc, copper, and iron aggregate Aβ and accumulate in Alzheimer’s disease (AD) plaques. Some metals are increased in AD vs. control serum. The authors examined levels of 12 metals in serum of 44 AD and 41 control subjects. Zinc decreased from 12.3 to 10.9 μmol/L (means, p = 0.0007). Arsenic positively correlated with Mini-Mental State Examination score (p < 0.0001). Zinc deposition in brain amyloid might deplete zinc from other body compartments, such as serum. The arsenic correlation might be caused by the major contribution of seafood consumption to intake of both arsenic and docosahexaenoic acid, of which the latter may delay AD.  相似文献   
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In 2009, Massachusetts (MA) Department of Public Health (DPH) implemented new regulations that required public schools in the state to measure height and weight, determine body mass index (BMI), and notify parents of children in grades 1, 4, 7, and 10 of their child's weight status. After 3 years of implementation, MA DPH recently abandoned parental notification of school‐based BMI screening results citing several concerns including flaws in the ability to monitor the way that the BMI screening results were communicated from the schools to parents/guardians and some reports of breaches in confidentiality of students' measurements. In this article, we review implementation issues that could have impacted the success of the MA DPH regulation as well as lessons to be learned and potentially applied to future childhood obesity efforts.  相似文献   
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