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1.
E. M. Peterman C. Sullivan M. F. Goody I. Rodriguez-Nunez J. A. Yoder C. H. Kim 《Infection and immunity》2015,83(1):430-440
Mitochondria are known primarily as the location of the electron transport chain and energy production in cells. More recently, mitochondria have been shown to be signaling centers for apoptosis and inflammation. Reactive oxygen species (ROS) generated as by-products of the electron transport chain within mitochondria significantly impact cellular signaling pathways. Because of the toxic nature of ROS, mitochondria possess an antioxidant enzyme, superoxide dismutase 2 (SOD2), to neutralize ROS. If mitochondrial antioxidant enzymes are overwhelmed during severe infections, mitochondrial dysfunction can occur and lead to multiorgan failure or death. Pseudomonas aeruginosa is an opportunistic pathogen that can infect immunocompromised patients. Infochemicals and exotoxins associated with P. aeruginosa are capable of causing mitochondrial dysfunction. In this work, we describe the roles of SOD2 and mitochondrial ROS regulation in the zebrafish innate immune response to P. aeruginosa infection. sod2 is upregulated in mammalian macrophages and neutrophils in response to lipopolysaccharide in vitro, and sod2 knockdown in zebrafish results in an increased bacterial burden. Further investigation revealed that phagocyte numbers are compromised in Sod2-deficient zebrafish. Addition of the mitochondrion-targeted ROS-scavenging chemical MitoTEMPO rescues neutrophil numbers and reduces the bacterial burden in Sod2-deficient zebrafish. Our work highlights the importance of mitochondrial ROS regulation by SOD2 in the context of innate immunity and supports the use of mitochondrion-targeted ROS scavengers as potential adjuvant therapies during severe infections. 相似文献
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Familial risk and heritability of intellectual disability: a population-based cohort study in Sweden
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Patterns of care: an analysis of the quality of nutritional care routinely provided to elderly hospitalized veterans 总被引:2,自引:0,他引:2
D H Sullivan M S Moriarty R Chernoff D A Lipschitz 《JPEN. Journal of parenteral and enteral nutrition》1989,13(3):249-254
To assess the adequacy of the nutritional care provided, a prospective noninterventional study was carried out on 250 randomly selected patients aged 65 and over who were admitted to a Veterans Administration Hospital. Of this group, 97 patients (39%) were found to be at high risk of having clinically significant protein-energy malnutrition. In 43 cases (17%), an assessment of the patient's nutritional status was not possible because the available data were inadequate. No patient had a diagnosis of malnutrition recorded on the problem list. Only 13 percent of the high-risk patients received some form of nutrition support therapy; 10 (10%) received oral supplements, and four (4%) were started on enteral feedings. Patients who received enteral feedings experienced a high rate of complications resulting from use of the feeding tubes. Over all, none of the high risk study patients received optimal nutrition support therapy. These findings indicate that elderly patients hospitalized in the Veterans Administration hospital in this study are usually not screened appropriately for protein-energy malnutrition, the diagnosis is frequently missed or ignored, and nutrition support therapy is underutilized and often ineffectually managed. 相似文献
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It is widely believed that family planning has important benefits for both maternal and child health. Despite this, little work has been done to quantify the potential effect of family planning in reducing maternal mortality. This paper assesses the impact of family planning in averting maternal deaths, and discusses the overall ability of risk strategies to address the bulk of maternal mortality. The practical difficulties of providing effective contraception to populations with high maternal mortality are addressed, and the need for maternal health care services as an adjunct to useful family planning programs is emphasized. Although family planning cannot by itself cause a substantial reduction in risk of pregnancy, the combined strategies of general fertility reduction, abortion services, and family planning for high-risk groups might effectively address about half of all maternal mortality in the developing world. Pregnancy and delivery care have the potential for saving large numbers of lives with appropriate interventions. It is concluded that reproductive risks can be reduced only by preventing unwanted pregnancies and protecting maternal health during wanted ones. 相似文献