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KA Hodgkinson SP Connors N Merner A Haywood T‐L Young WJ McKenna B Gallagher F Curtis AS Bassett PS Parfrey 《Clinical genetics》2013,83(4):321-331
To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility. 相似文献
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BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8) 相似文献
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PS Spencer K Vandemaele M Richer VS Palmer S Chungong M Anker Y Ayana ML Opoka BN Klaucke A Quarello JK Tumwine 《African health sciences》2013,13(2):183-204
Background
Nodding Syndrome is a seizure disorder of children in Mundri County, Western Equatoria, South Sudan. The disorder is reported to be spreading in South Sudan and northern Uganda.Objective
To describe environmental, nutritional, infectious, and other factors that existed before and during the de novo 1991 appearance and subsequent increase in cases through 2001.Methods
Household surveys, informant interviews, and case-control studies conducted in Lui town and Amadi village in 2001–2002 were supplemented in 2012 by informant interviews in Lui and Juba, South Sudan.Results
Nodding Syndrome was associated with Onchocerca volvulus and Mansonella perstans infections, with food use of a variety of sorghum (serena) introduced as part of an emergency relief program, and was inversely associated with a history of measles infection. There was no evidence to suggest exposure to a manmade neurotoxic pollutant or chemical agent, other than chemically dressed seed intended for planting but used for food. Food use of cyanogenic plants was documented, and exposure to fungal contaminants could not be excluded.Conclusion
Nodding Syndrome in South Sudan has an unknown etiology. Further research is recommended on the association of Nodding Syndrome with onchocerciasis/mansonelliasis and neurotoxins in plant materials used for food. 相似文献27.
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Maggie KM Ma Desmond YH Yap Terence PS Yip Sing Leung Lui Wai Kei Lo 《Nephrology (Carlton, Vic.)》2013,18(5):365-368
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture. 相似文献
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Oxidative metabolism of the human eosinophil 总被引:14,自引:1,他引:14
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst. 相似文献
30.
Darrell J. Gaskin Roland J. Thorpe Jr Emma E. McGinty Kelly Bower Charles Rohde J. Hunter Young Thomas A. LaVeist Lisa Dubay 《American journal of public health》2014,104(11):2147-2155
Objectives. We sought to determine the role of neighborhood poverty and racial composition on race disparities in diabetes prevalence.Methods. We used data from the 1999–2004 National Health and Nutrition Examination Survey and 2000 US Census to estimate the impact of individual race and poverty and neighborhood racial composition and poverty concentration on the odds of having diabetes.Results. We found a race–poverty–place gradient for diabetes prevalence for Blacks and poor Whites. The odds of having diabetes were higher for Blacks than for Whites. Individual poverty increased the odds of having diabetes for both Whites and Blacks. Living in a poor neighborhood increased the odds of having diabetes for Blacks and poor Whites.Conclusions. To address race disparities in diabetes, policymakers should address problems created by concentrated poverty (e.g., lack of access to reasonably priced fruits and vegetables, recreational facilities, and health care services; high crime rates; and greater exposures to environmental toxins). Housing and development policies in urban areas should avoid creating high-poverty neighborhoods.In the United States, 25.6 million or 11.3% of adults aged 20 years and older had diabetes in 2010.1 Non-Hispanic Blacks had the highest prevalence at 12.6% compared with non-Hispanic Whites at 7.1%.1 Traditional explanations for the observed race disparity in diabetes prevalence include differences in health behaviors, socioeconomic factors, family history of diabetes, biological factors, and environmental factors.2–4 Little work has been conducted to understand how individual and environment-level factors operate together to produce disparities in diabetes prevalence.A relatively new line of research has begun to show that risk of diabetes is associated with neighborhood attributes that are also associated with race. Auchincloss et al. found that higher diabetes rates were related to lack of availability of neighborhood resources that support physical activity and healthy nutrition.5 Schootman et al. found that poor housing conditions were associated with diabetes prevalence.6 Black neighborhoods are more likely to be characterized by these risk factors (i.e., having food deserts, being less likely to have recreational facilities, and tending to have lower-quality housing than White neighborhoods).7–18 As such it stands to reason that failing to adjust national estimates of diabetes prevalence for these social conditions might influence perceptions of diabetes disparities. LaVeist et al. compared disparities in diabetes in an urban, racially integrated, low-income community with a national sample from the National Health Interview Survey.19,20 They found that when urban Whites and Blacks resided in the same low-income community, the race disparity in diabetes prevalence disappeared, largely because the prevalence rate for Whites increased substantially.19 Ludwig et al. used data from the Moving to Opportunity demonstration project and found a lower prevalence of diabetes among low-income adults who moved from high-poverty neighborhoods to low-poverty neighborhoods compared with low-income adults who moved from a high-poverty neighborhood to another high-poverty neighborhood.21 Findings from these studies suggest the need to further explore the role of place in race disparities in diabetes.We explored whether the nexus of race, poverty, and neighborhood racial composition and poverty concentration illuminates the race disparities in diabetes. Specifically, we examined (1) whether diabetes prevalence increases in predominantly Black neighborhoods compared with predominantly White neighborhoods, (2) whether diabetes prevalence is higher in poor neighborhoods than in nonpoor neighborhoods, and (3) whether the impact of neighborhood racial composition and poverty concentration on the risk of diabetes varies by race. We hypothesized that residential segregation and concentrated poverty (1) increase Black individuals’ exposure to environmental risks associated with poor health, (2) reduce their access to community amenities that promote good health and healthy behaviors, and (3) limit their access to social determinants that promote good health such as quality jobs, education, public safety, and social networks.7,22–24 相似文献