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101.
Desai V, Donsante A, Swoboda KJ, Martensen M, Thompson J, Kaler SG. Favorably skewed X‐inactivation accounts for neurological sparing in female carriers of Menkes disease. Classical Menkes disease is an X‐linked recessive neurodegenerative disorder caused by mutations in ATP7A, which is located at Xq13.1‐q21. ATP7A encodes a copper‐transporting P‐type ATPase and plays a critical role in development of the central nervous system. With rare exceptions involving sex chromosome aneuploidy or X‐autosome translocations, female carriers of ATP7A mutations are asymptomatic except for subtle hair and skin abnormalities, although the mechanism for this neurological sparing has not been reported. We studied a three‐generation family in which a severe ATP7A mutation, a 5.5‐kb genomic deletion spanning exons 13 and 14, segregated. The deletion junction fragment was amplified from the proband by long‐range polymerase chain reaction and sequenced to characterize the breakpoints. We screened at‐risk females in the family for this junction fragment and analyzed their X‐inactivation patterns using the human androgen‐receptor (HUMARA) gene methylation assay. We detected the junction fragment in the proband, two obligate heterozygotes, and four of six at‐risk females. Skewed inactivation of the X chromosome harboring the deletion was noted in all female carriers of the deletion (n = 6), whereas random X‐inactivation was observed in all non‐carriers (n = 2). Our results formally document one mechanism for neurological sparing in female carriers of ATP7A mutations. Based on review of X‐inactivation patterns in female carriers of other X‐linked recessive diseases, our findings imply that substantial expression of a mutant ATP7A at the expense of the normal allele could be associated with neurologic symptoms in female carriers of Menkes disease and its allelic variants, occipital horn syndrome, and ATP7A‐related distal motor neuropathy. 相似文献
102.
KJ Champion C Bunag AL Estep JR Jones CH Bolt RC Rogers KA Rauen DB Everman 《Clinical genetics》2011,79(5):468-474
Champion KJ, Bunag C, Estep AL, Jones JR, Bolt CH, Rogers RC, Rauen KA, Everman DB. Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome. BRAF, the protein product of BRAF, is a serine/threonine protein kinase and one of the direct downstream effectors of Ras. Somatic mutations in BRAF occur in numerous human cancers, whereas germline BRAF mutations cause cardio‐facio‐cutaneous (CFC) syndrome. One recurrent somatic mutation, p.V600E, is frequently found in several tumor types, such as melanoma, papillary thyroid carcinoma, colon cancer, and ovarian cancer. However, a germline mutation affecting codon 600 has never been described. Here, we present a patient with CFC syndrome and a de novo germline mutation involving codon 600 of BRAF, thus providing the first evidence that a pathogenic germline mutation involving this critical codon is not only compatible with development but can also cause the CFC phenotype. In vitro functional analysis shows that this mutation, which replaces a valine with a glycine at codon 600 (p.V600G), leads to increased ERK and ELK phosphorylation compared to wild‐type BRAF but is less strongly activating than the cancer‐associated p.V600E mutation. 相似文献
103.
Background
Hepatitis E, generally known to be transmitted faeco-orally, has been shown to have significant transmission by blood borne route. Paucity of data on asymptomatic viremia in blood donors and higher incidence of Hepatitis E in haemodialysis patients and thalassemics mandate a prospective study of blood recipients to elucidate the exact incidence and natural history of post transfusion Hepatitis E.Methods
A total of 2000 recipients of blood or blood products transfusion were followed up for two months to detect development of post transfusion Hepatitis E, by clinical examination, transaminases and immunoglobulin M anti hepatitis E virus (IgM anti HEV). Estimation of hepatitis E virus ribonucleic acid (HEV RNA) was done in patients with elevated levels of transaminases.Result
Out of 2000 patients, 5(0.25%) were positive for IgM anti HEV at the time of transfusion and were excluded from the study. Rest of 1995 patients were followed up for two months post transfusion. A total of 1303 (65.3%) patients were followed up for two months and 1636 (82.0%) patients at least once in two visits. None of the followed up patients reported development of jaundice or had clinically evident hepatitis, although 62 patients had raised transaminases detected at either one or both the visits.Conclusion
All followed up patients were tested for IgM anti HEV at both the visits and none were found to be positive. Patients with raised transaminases were subjected to HEV RNA and all were found to be negative.Key Words: Hepatitis E, Post transfusion, Parenteral transmission 相似文献104.
Reynolds KD Buller DB Yaroch AL Maloy J Geno CR Cutter GR 《Journal of health communication》2008,13(7):619-636
Few family-based interventions to increase sun safe behavior among adolescents have been evaluated. The present study tested an intervention that included tailored and nontailored print communications delivered by mail to adolescents (age 11 to 15) and their parents who were also participating in an evaluation of an in-school intervention. The use of sunscreen, protective clothing, and avoidance of the sun were promoted, and family communication and environmental change strategies were fostered. Adolescents and their parents were pretested in May of 2002 and posttested from August to October. Adolescents (N = 599) were stratified on experimental condition in the in-school study (in-school intervention vs control) and randomly were assigned from within strata to receive (N = 288) or not receive (N = 311) the summer intervention materials. No statistically significant effects were found for adolescents between the randomized experimental conditions. Parents' had increased knowledge (F = 5.52, p < .05) and propensity to have their child wear sunglasses (F = 4.07, p < .05). Greater program exposure/engagement led to enhanced sun protection behavior (e.g., fewer sunburns) and psychosocial factors among adolescents and parents. Greater exposure/engagement led to improvements in family interaction and home environment (e.g., shade audit completed). Future research is needed on exposure/engagement with family-based health messaging and on family-based sun safety programs for adolescents. 相似文献
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108.
Statin therapy may prevent an excessive inflammatory response after cardiopulmonary bypass for cardiac surgery. In a recent
issue of Critical Care, Morgan and colleagues present data from a well-conducted systematic review and meta-analysis of randomised controlled trials
using inflammatory markers as primary outcome measure. They find that pre-operative statin therapy, compared with placebo,
may reduce various post-operative markers of systemic inflammation (IL-6, IL-8, C-reactive protein, tumour necrosis factor-alpha).
Their ability to make definitive conclusions is limited, however, by the suboptimal methodological quality of the primary
studies. Their review suggests that ICU researchers should focus on developing valid surrogate markers and use these to accurately
describe the mechanisms and effectiveness of novel therapies before proceeding to large pragmatic trials using mortality as
primary outcome. 相似文献
109.
Objective To explore the characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Seven patients with arrhythmogenic right ventricular cardiomyopathy and 34 members of three families were studied. All patients and family members underwent history collection, clinical examination, electrocardiogram (ECG), two-dimensional echocardiography (2-DE) and a signal averaging electrocardiogram. Programmed ventricular stimulation was performed in five patients. Results All patients and family members had normal morphologic characteristics and normal function of the left ventricular by 2-DE. Fourteen persons had abnormal findings indicating ARVC. Five had enlargement of the right ventricular with diffused hypocontractility, eight had thin and systolic bulging in the focal anterior wall with hypokinesia and one had bulging of the inferior wall. Twenty-five persons (seven patients and 18 family members) had abnormal findings in ECG. Positive ventricular late potential was recorded in 13 persons (six patients). Two to three monomorphic ventricular tachycardia (VT) with left bundle branch block (LBBB) configurations were induced in five patients. Ventricular fibrillation was induced in two patients during the electrophysiologic study (EPS). Five patients had very high pacing threshold and/or ineffective pacing in one or many regions of the right ventricle. Two members of one family died suddenly. One member was a dwarf with ARVC. Spontaneous VT with a left bundle branch block (LBBB) configuration was recorded in five patients, polymorphic VT with extremely short coupling interval in one, and premature ventricular complexes with LBBB configuration in 12 (six patients). Conclusion Our familial study strongly suggests that ARVC may be a hereditary disease and it is helpful in the diagnosis and detection of ARVC. The most common manifestations were abnormal structure and function of the right ventricle and abnormal ECG of repolarization and ventricular arrhythmia which originates from the right ventricle. 相似文献
110.
Hepatic arterial chemotherapy: role of angiography 总被引:2,自引:0,他引:2
Hepatic arterial infusion chemotherapy increases the hepatic concentration of chemotherapeutic agents without increasing systemic toxicity. Both percutaneous (most commonly left transbrachial) and surgical approaches are currently used for infusion catheter placement. Surgical catheter and pump placement has proved to be a reliable means of delivering drugs to the liver and has been commonly used for hepatic arterial chemotherapy for metastatic colorectal carcinoma. Meticulous angiographic evaluation of the hepatic vascular anatomy, its variations, and hemodynamics is necessary for correct catheter placement to achieve total liver perfusion without significant extrahepatic perfusion. Satisfactory hepatic perfusion should be documented before drug infusion. Hepatic arterial radionuclide flow imaging with technetium-99m-labeled macroaggregated serum albumin remains the most reliable means of assessing hepatic perfusion following catheter placement. Transcatheter techniques have been used to facilitate catheter placement, to prevent gastrointestinal drug toxicity, and to correct unsatisfactory perfusion following surgical catheter placement. 相似文献