119 research outputs found

    Regulation of ASIC channels by a stomatin/STOML3 complex located in a mobile vesicle pool in sensory neurons

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    A complex of stomatin-family proteins and acid-sensing (proton-gated) ion channel (ASIC) family members participate in sensory transduction in invertebrates and vertebrates. Here, we have examined the role of the stomatin-family protein stomatin-like protein-3 (STOML3) in this process. We demonstrate that STOML3 interacts with stomatin and ASIC subunits and that this occurs in a highly mobile vesicle pool in dorsal root ganglia (DRG) neurons and Chinese hamster ovary cells. We identify a hydrophobic region in the N-terminus of STOML3 that is required for vesicular localization of STOML3 and regulates physical and functional interaction with ASICs. We further characterize STOML3-containing vesicles in DRG neurons and show that they are Rab11-positive, but not part of the early-endosomal, lysosomal or Rab14-dependent biosynthetic compartment. Moreover, uncoupling of vesicles from microtubules leads to incorporation of STOML3 into the plasma membrane and increased acid-gated currents. Thus, STOML3 defines a vesicle pool in which it associates with molecules that have critical roles in sensory transduction. We suggest that the molecular features of this vesicular pool may be characteristic of a ‘transducosome’ in sensory neurons

    PIN71 QUALITY OF LIFE (QOL) AND OTHER ENDPOINTS COMPARISON IN THE TREATMENT OF FACIAL LIPOATROPHY WITH INJECTION OF POLY-L-LACTIC ACID

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    Context: Longitudinal data on bone mineral density(BMD) in children and adolescents with Prader-Willi Syndrome (PWS) during long-term GH treatment are not available. Objective: This study aimed to determine effects of long-term GH treatment and puberty on BMD of total body (BMDTB), lumbar spine (BMDLS), and bone mineral apparent density of the lumbar spine (BMAD(LS)) in children with PWS. Design and Setting: This was a prospective longitudinal study of a Dutch PWS cohort. Participants: Seventy-seven children with PWS who remained prepubertal during GH treatment for 4 years and 64 children with PWS who received GH treatment for 9 years participated in the study. Intervention: The children received GH treatment, 1 mg/m(2)/day (congruent to 0.035 mg/kg/d). Main Outcome Measures: BMDTB, BMDLS, and BMAD(LS) was measured by using the same dual-energy x-ray absorptiometry machine for all annual measurements. Results: In the prepubertal group, BMDTB standard deviation score (SDS) and BMDLSSDS significantly increased during 4 years of GH treatment whereas BMAD(LS)SDS remained stable. During adolescence, BMDTBSDS and BMAD(LS)SDS decreased significantly, in girls from the age of 11 years and in boys from the ages of 14 and 16 years, respectively, but all BMD parameters remained within the normal range. Higher Tanner stages tended to be associated with lower BMDTBSDS (P = .083) and a significantly lowerBMAD(LS)SDS (P = .016). After 9 years of GH treatment, lean body mass SDS was the most powerful predictor of BMDTBSDS and BMDLSSDS in adolescents with PWS. Conclusions: This long-term GH study demonstrates that BMDTB, BMDLS, and BMAD(LS) remain stable in prepubertal children with PWS but decreases during adolescence, parallel to incomplete pubertal development. Based on our findings, clinicians should start sex hormone therapy from the age of 11 years in girls and 14 years in boys unless there is a normal progression of puberty

    Prevalence of pulmonary TB and spoligotype pattern of Mycobacterium tuberculosis among TB suspects in a rural community in Southwest Ethiopia

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    <p>Abstract</p> <p>Background</p> <p>In Ethiopia where there is no strong surveillance system and state of the art diagnostic facilities are limited, the real burden of tuberculosis (TB) is not well known. We conducted a community based survey to estimate the prevalence of pulmonary TB and spoligotype pattern of the <it>Mycobacterium tuberculosis </it>isolates in Southwest Ethiopia.</p> <p>Methods</p> <p>A total of 30040 adults in 10882 households were screened for pulmonary TB in Gilgel Gibe field research centre in Southwest Ethiopia. A total of 482 TB suspects were identified and smear microscopy and culture was done for 428 TB suspects. Counseling and testing for HIV/AIDS was done for all TB suspects. Spoligotyping was done to characterize the <it>Mycobacterium tuberculosis </it>isolates.</p> <p>Results</p> <p>Majority of the TB suspects were females (60.7%) and non-literates (83.6%). Using smear microscopy, a total of 5 new and 4 old cases of pulmonary TB cases were identified making the prevalence of TB 30 per 100,000. However, using the culture method, we identified 17 new cases with a prevalence of 76.1 per 100,000. There were 4.3 undiagnosed pulmonary TB cases for every TB case who was diagnosed through the passive case detection mechanism in the health facility. Eleven isolates (64.7%) belonged to the six previously known spoligotypes: T, Haarlem and Central-Asian (CAS). Six new spoligotype patterns of <it>Mycobacterium tuberculosis</it>, not present in the international database (SpolDB4) were identified. None of the rural residents was HIV infected and only 5 (5.5%) of the urban TB suspects were positive for HIV.</p> <p>Conclusion</p> <p>The prevalence of TB in the rural community of Southwest Ethiopia is low. There are large numbers of undiagnosed TB cases in the community. However, the number of sputum smear-positive cases was very low and therefore the risk of transmitting the infection to others may be limited. Active case finding through health extension workers in the community can improve the low case detection rate in Ethiopia. A large scale study on the genotyping of <it>Mycobacterium tuberculosis </it>in Ethiopia is crucial to understand transmission dynamics, identification of drug resistant strains and design preventive strategies.</p

    Primrose syndrome: Characterization of the phenotype in 42 patients

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    Primrose syndrome (PS; MIM# 259050) is characterized by intellectual disability (ID), macrocephaly, unusual facial features (frontal bossing, deeply set eyes, down-slanting palpebral fissures), calcified external ears, sparse body hair and distal muscle wasting. The syndrome is caused by de novo heterozygous missense variants in ZBTB20. Most of the 29 published patients are adults as characteristics appear more recognizable with age. We present 13 hitherto unpublished individuals and summarize the clinical and molecular findings in all 42 patients. Several signs and symptoms of PS develop during childhood, but the cardinal features, such as calcification of the external ears, cystic bone lesions, muscle wasting, and contractures typically develop between 10 and 16 years of age. Biochemically, anemia and increased alpha-fetoprotein levels are often present. Two adult males with PS developed a testicular tumor. Although PS should be regarded as a progressive entity, there are no indications that cognition becomes more impaired with age. No obvious genotype-phenotype correlation is present. A subgroup of patients with ZBTB20 variants may be associated with mild, nonspecific ID. Metabolic investigations suggest a disturbed mitochondrial fatty acid oxidation. We suggest a regular surveillance in all adult males with PS until it is clear whether or not there is a truly elevated risk of testicular cancer.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site.published version, accepted version (12 month embargo) submitted versio

    Prejudice and misconceptions about tuberculosis and HIV in rural and urban communities in Ethiopia: a challenge for the TB/HIV control program

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    <p>Abstract</p> <p>Background</p> <p>In Ethiopia, where HIV and tuberculosis (TB) are very common, little is known about the prejudice and misconceptions of rural communities towards People living with HIV/AIDS (PLHA) and TB.</p> <p>Methods</p> <p>We conducted a cross sectional study in Gilgel Gibe Field Research area (GGFRA) in southwest Ethiopia to assess the prejudice and misconceptions of rural and urban communities towards PLHA and TB. The study population consisted of 862 randomly selected adults in GGFRA. Data were collected by trained personnel using a pretested structured questionnaire. To triangulate the findings, 8 focus group discussions among women and men were done.</p> <p>Results</p> <p>Of the 862 selected study participants, 750(87%) accepted to be interviewed. The mean age of the respondents was 31.2 (SD ± 11.0). Of the total interviewed individuals, 58% of them were females. More than half of the respondents did not know the possibility of transmission of HIV from a mother to a child or by breast feeding. For fear of contagion of HIV, most people do not want to eat, drink, and share utensils or clothes with a person living with HIV/AIDS. A higher proportion of females [OR = 1.5, (95% CI: 1.0, 2.2)], non-literate individuals [OR = 2.3, (95%CI: 1.4, 3.6)], rural residents [OR = 3.8, (95%CI: 2.2, 6.6)], and individuals who had poor knowledge of HIV/AIDS [OR = 2.8, (95%CI: 1.8, 2.2)] were more likely to have high prejudice towards PLHA than respectively males, literates, urban residents and individuals with good knowledge. Exposure to cold air was implicated as a major cause of TB. Literates had a much better knowledge about the cause and methods of transmission and prevention of TB than non-literates. More than half of the individuals (56%) had high prejudice towards a patient with TB. A larger proportion of females [OR = 1.3, (95% CI: 1.0, 1.9)] and non-literate individuals [OR = 1.4, (95% CI: 1.1, 2.0)] had high prejudice towards patients with TB than males and literate individuals.</p> <p>Conclusion</p> <p>TB/HIV control programs in collaboration with other partners should invest more in social mobilization and education of the communities to rectify the widespread prejudice and misconceptions.</p

    Reducing uncertainty in fatigue life limits of turbine engine alloys

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    In probabilistic design of materials for fracture-critical components in modern military turbine engines, a typical maximum design target risk (DTR) is 5 X 10-8 component failures/engine flight hour. This metric underscores the essential role of safety in a design process that simultaneously strives to achieve performance, efficiency, reliability, and affordability throughout the life cycle of the engine. Traditionally, the design and life management approaches for engine materials have typically relied on extensive testing programs to produce large databases of fatigue data, from which statistically based life limits are derived by extrapolation from the mean fatigue behavior. However, we have found that the statistical behavior of fatigue lifetimes under a given test condition often exhibits a bimodal form, and that the trends in mean vs. minimum fatigue lifetime typically respond differently to loading or to microstructural variables. Under such circumstances, the underlying life-limiting mechanisms appear to exhibit a probabilistic microstructural hierarchy in fatigue resistance that is controlled by susceptibility of local microstructural neighborhoods to early damage and the growth of small cracks. These findings suggest that significant opportunities may exist for reductions in uncertainty in materials life-cycle prediction and management, if such hierarchies can be understood and controlled. This paper explores the potential implications of these findings, and a number of possible approaches are suggested for incorporating the insights of life-limiting fatigue into methods of integrated computational materials engineering (ICME) to support optimized life-cycle design of materials and components in turbine engines. Benefits of this approach appear to include substantial improvements in model accuracy, coupled with reduced requirements for materials testing, potentially leading to a significant reduction in the time and cost to develop, validate, transition, and implement new, more fatigue resistant alloys

    Smith-Lemli-Opitz syndrome and the DHCR7 gene

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    Smith-Lemli-Opitz syndrome, a severe developmental disorder associated with multiple congenital anomalies, is caused by a defect of cholesterol biosynthesis. Low cholesterol and high concentrations of its direct precursor, 7-dehydrocholesterol, in plasma and tissues are the diagnostic biochemical hallmarks of the syndrome. The plasma sterol concentrations correlate with severity and disease outcome. Mutations in the DHCR7 gene lead to deficient activity of 7-dehydrocholesterol reductase (DHCR7), the final enzyme of the cholesterol biosynthetic pathway. The human DHCR7 gene is localised on chromosome 11q13 and its structure has been characterized. Ninety-one different mutations in the DHCR7 gene have been published to date. This paper is a review of the clinical, biochemical and molecular genetic aspect
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