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211.
Detection of a homozygous four base pair deletion in the protein X gene in a case of pyruvate dehydrogenase complex deficiency 总被引:2,自引:0,他引:2
Ling M; McEachern G; Seyda A; MacKay N; Scherer SW; Bratinova S; Beatty B; Giovannucci-Uzielli ML; Robinson BH 《Human molecular genetics》1998,7(3):501-505
While the presence of a lipoyl-containing protein (protein X) separate from
lipoyl transacetylase in the pyruvate dehydrogenase complex (PDC) has been
known for some time, until recently only the cDNA for the yeast enzyme has
been cloned. We have cloned, sequenced and characterized the cDNA encoding
the human protein X and localized the protein X gene to chromosome 11p13.
We also report here a new case of protein X deficiency identified
immunologically, with decreased activity of PDC and without mutations in
the E1alpha subunit or E1beta subunit. We report that the cDNA and gene of
this patient for protein X has a homozygous 4 bp deletion, specifically in
the putative mitochondrial targeting signal sequence which results in a
premature stop codon. This is the first documented case of a molecular
defect in pyruvate dehydrogenase protein X.
相似文献
212.
Mutations in a novel gene, VMD2, encoding a protein of unknown properties cause juvenile-onset vitelliform macular dystrophy (Best's disease) 总被引:15,自引:0,他引:15
Marquardt A; Stohr H; Passmore LA; Kramer F; Rivera A; Weber BH 《Human molecular genetics》1998,7(9):1517-1525
Vitelliform macular dystrophy (Best's disease) is an autosomal dominant,
early-onset form of macular degeneration in which the primary defect is
thought to occur at the level of the retinal pigment epithelium. Genetic
linkage has mapped the disease locus to chromosome 11q12-q13.1 within a 980
kb interval flanked by markers at loci D11S4076 and uteroglobin. To
identify the disease gene, we systematically characterized genes from
within the critical region and analysed the coding regions for mutations in
12 patients from large multigeneration Best's disease families. Following
this approach, we identified a novel gene of unknown function carrying
heterozygous mutations in all 12 probands. Of these, 10 result in distinct
missense mutations of amino acids that are highly conserved throughout
evolution, spanning a phylogenetic distance from Caenorhabditis elegans to
human, and include V9M, A10T, W24C, R25Q, R218Q, Y227N, Y227C, V235M, P297A
and F305S. One deletion mutation, DeltaI295, was found in two families and
segregates with the disease in both cases. Northern blot analysis reveals
tissue-specific expression for this gene, exclusively in the retinal
pigment epithelium. In conclusion, our data provide strong evidence that
mutations in the gene that we have identified cause Best's disease.
相似文献
213.
214.
Gabrielle Capone Caroline Lojacono Fatma Al-Bayitee Shayan Makvandi Teresa Hennon Brian Wrotniak Rabheh Abdul-Aziz 《Reumatologia》2021,59(4):244
ObjectivesOur aim is to identify the presence of serologically active clinically quiescent (SACQ) episodes in pediatric systemic lupus erythematosus (SLE) patients. We aim to identify serologic biomarkers associated with SACQ episodes and discuss risks and benefits of escalating treatments.Material and methodsWe evaluated 25 pediatric SLE patients, 13 of whom experienced SACQ episodes. Serologically active clinically quiescent was defined as two consecutive clinic visits without any clinical symptoms or clinical examination findings of a lupus flare with a clinical Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score of zero, but either elevated anti-ds-DNA antibodies or low complement (C3 and/or C4) levels.ResultsAmong the 13 patients who experienced a SACQ episode, there were a total of 24 episodes, with each patient experiencing 1–4 SACQ episodes. Erythrocyte sedimentation rate (ESR) was the most commonly elevated laboratory marker in a SACQ episode, followed by low hemoglobin levels, and then elevated anti-dsDNA antibodies. Of the 17 episodes treated during a SACQ episode, 15 (88%) did not progress to a clinical flare within six months, while two did. Furthermore, of the 7 patients who were not treated during their SACQ episode, 2 (29%) continued to be SACQ without flare, whereas 5 led to a clinical flare within six months.ConclusionsSerologically active clinically quiescent episodes were identified in pediatric SLE patients, suggesting that the presence of SACQ is not limited to adults with SLE. Serologic markers such as increased ESR, hemoglobin, and elevated anti-dsDNA antibodies are preliminarily associated with pediatric SACQ episodes. Treating these SACQ episodes in pediatric SLE patients was less likely to lead to a clinical flare within six months when compared to not treating (p < 0.05). More research with a larger sample size is needed to define SACQ episodes, determine the prevalence in pediatric SLE patients, and establish SACQ treatment guidelines. 相似文献
215.
T Kron D Willis F Bignell J Martland S Donnell S May BH Chua 《Journal of Medical Imaging and Radiation Oncology》2009,53(4):412-418
Introduction: Inconsistencies in contouring target volumes for partial breast irradiation (PBI) may result in geographical misses and compromise treatment outcomes. The present study aimed to (1) determine the variability of the target volumes contoured and treatment plans generated by participating centres in credentialing for participation in a multicentre PBI trial; and (2) assess dosimetric changes when standardized target volumes were used. Methods: The CT image sets of two de‐identified patients post‐breast conserving surgery were used. Contouring of the target volumes for the two cases was performed and a treatment plan as per protocol specifications was generated for each case by the seven participating centres. Planning of both cases was repeated by five centres using a set of standardized target volumes to evaluate resulting dosimetric changes in the treatment plans. Results: The surgical cavity, the part of the planning target volume used for dose evaluation and ipsilateral whole breast volumes contoured by the centres varied by 25%, 16% and 21% (1 standard deviation), respectively. The dosimetric variations found when the standardized target volumes were used were smaller than those noted when centre‐specific volumes were used. The volumes of the ipsilateral lungs receiving 30% of the prescribed dose and the volumes of the ipsilateral whole breasts receiving 95% and 50% of the prescribed dose were reduced in the treatment plans developed using the standardized target volumes. Conclusions: Given the impact of contouring on dose distributions, quality assurance procedures in clinical trials of PBI need to take into account both the technical approaches and the contouring. 相似文献
216.
Gestational weight gain and risk of overweight in the offspring at age 7 y in a multicenter, multiethnic cohort study 总被引:1,自引:0,他引:1
Wrotniak BH Shults J Butts S Stettler N 《The American journal of clinical nutrition》2008,87(6):1818-1824
BACKGROUND: The earliest determinants of obesity may operate during intrauterine life, and gestational weight gain may influence the intrauterine environment in a way that may affect the risk of overweight in the offspring. OBJECTIVE: The purpose of this study was to examine the association of gestational weight gain with offspring overweight. DESIGN: This was a retrospective cohort study of 10,226 participants from the Collaborative Perinatal Project (1959-1972). Anthropometric and sociodemographic variables were assessed during gestation, at birth, and at age 7 y. The association between gestational weight gain and offspring overweight at 7 y was examined after adjustment for important confounding factors. RESULTS: The odds of overweight in offspring at age 7 y increased by 3% for every 1 kg of gestational weight gain (adjusted odds ratio: 1.03; 95% CI: 1.02, 1.05). When gestational weight gain was examined using Institute of Medicine guidelines, the odds of overweight was 48% greater for children of mothers who gained more than the weight gain recommendations than for children of mothers who met the weight gain guidelines (adjusted OR: 1.48; 95% CI: 1.06, 2.06). The association remained significant after additional adjustment for birth weight. The association between gestational weight gain and overweight in the offspring was strongest for women who were underweight before pregnancy (P for interaction < 0.01). CONCLUSION: Helping pregnant women to meet the recommended weight gain during pregnancy may be an important and novel strategy for preventing pediatric obesity. 相似文献
217.
218.
219.
Sisto SA; Tapp WN; LaManca JJ; Ling W; Korn LR; Nelson AJ; Natelson BH 《QJM : monthly journal of the Association of Physicians》1998,91(7):465-473
We measured physical activity after strenuous exercise in 20 women with
chronic fatigue syndrome (CFS), compared to 20 sedentary healthy volunteers
who exercised no more than once per week. Activity was measured for 2 weeks
using a portable waist-worn vertical accelerometer. After the first week of
activity monitoring, all participants returned for a maximal treadmill
test, followed by continued activity monitoring for the second week. Five
activity measures were derived from the data: (i) average activity; (ii)
total activity; (iii) duration of waking day; (iv) duration; and (v) number
of daily rests. A repeated measures ANCOVA was used to determine post-
treadmill group differences accounting for pre-treadmill differences. There
was a significant reduction in overall average activity after the treadmill
test, with the greatest decrease on days 12 through 14. This reduction was
accompanied by a significant increase in the duration of the waking day and
number of daily rests. Thus, marked exertion does produce changes in
activity, but later than self-report would suggest, and are apparently not
so severe that CFS patients cannot compensate.
相似文献
220.
三七中人参三醇甙抗心律失常作用的研究 总被引:7,自引:0,他引:7
三七三醇甙(PTS)为三七的组分之一,能明显对抗乌头碱、BaCl2和肾上腺素诱发的实验性心律失常。PTS减慢大鼠心率,延长P-R和Q-Tc间期;减慢离体豚鼠右房自发频率;使异丙肾上腺素加速右房自发频率的量效-曲线右移并抑制最大效应。PTS与胺碘达隆作用相似,使离体豚鼠乳头状肌细胞电位APD和ERP显著延长,2相复极化斜率降低。PTS对上述动作电位的影响呈剂量依赖性关系。 相似文献