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1.
Mitochondrial diseases are a heterogeneous group of disorders in which a primary mitochondrial dysfunction is proven by morphological, biochemical, and genetic examinations. The mitral valve has important function in the regulation of blood flow from one chamber to another. Often, the mitral valve becomes abnormal with age, in Rheumatic fever or it is abnormal from birth (Congenital) or it can be destroyed by infection i.e. bacterial endocarditis and needs replacement. Myocardial function depends on energy produced by mitochondria and in any of these disease conditions, mitochondrial functions and enzyme activities may be impaired. With this in view, we analyzed the relationship between preoperative clinical conditions (as per New York heart Association) and extent of mitochondrial enzyme activities in damaged Human mitral valve in two types of heart disease such as Rheumatic Heart Disease (RHD) and Bacterial Endocarditis (BE). Thirty nine Patients undergoing cardiopulmonary bypass (CPB) for routine valvular heart surgery were included in the study. Controls included 11 normal porcine mitral valve samples without any evidence of heart disease. Mitochondrial enzymes like cytochrome oxidase (COX), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), citrate synthase (CS) and ATPase were determined. Mitochondrial COX, SDH, CS and Total ATPase activities were significantly decreased in disease condition like BE and RHD when compared with control (P<0.001). On the other hand as per New York Heart Association (NYHA) preoperative clinical classification, all the mitochondrial enzymes were significantly (p<0.05) impaired in class IV as compared with NYHA class I, II and III. Present study shows that impairment in the mitochondrial enzymes activities are more pronounced in bacterial endocarditis (BE). It also indicates that damage to mitochondrial enzymes are most pronounced in NYHA class IV.  相似文献   

2.
Short-chain acyl-CoA dehydrogenase (ACAD) deficiency is an extremely rare inherited mitochondrial disorder of fat metabolism. This belongs to a group of diseases known as fatty acid oxidation disorders. Screening programmes have provided evidence that all the fatty acid oxidation disorders combined are among the most common inborn errors of metabolism. Mitochondrial beta oxidation of fatty acids is an essential energy producing pathway. It is a particularly important pathway during prolonged periods of starvation and during periods of reduced caloric intake due to gastrointestinal illness or increased energy expenditure during febrile illness. The most common presentation is an acute episode of life threatening coma and hypoglycemia induced by a period of fasting due to defective hepatic ketogenesis. Here, the case of a 4 month old female patient who had seizures since the third day of her birth and persistent hypoglycemia is described. She was born to parents of second degree consanguinity after 10 years of infertility treatment. There was history of delayed cry after birth. Metabolic screening for TSH, galactosemia, 17-OHP, G6PD, cystic fibrosis, biotinidase were normal. Tandem mass spectrometric (TMS) screening for blood amino acids, organic acids, fatty acids showed elevated butyryl carnitine (C4) as 3.40 μmol/L (normal <2.00 μmol/L), hexanoyl carnitine (C6) as 0.92 μmol/L (normal <0.72 μmol/L), C4/C3 as 2.93 μmol/L (normal <1.18 μmol/L). The child was started immediately on carnitor syrup (carnitine) 1/2 ml twice daily. Limitation of fasting stress and dietary fat was advised. Baby responded well by gaining weight and seizures were controlled. Until now, less than 25 patients have been reported worldwide. The limited number of patients diagnosed until now is due to the rarity of the disorder resulting in under diagnosis.  相似文献   

3.
The cerebral sphingolipidoses which form part of a larger group of lysosomal disorders can be detected and conclusively confirmed by the demonstration of the relevent enzyme deficiency in easily available tissue samples like serum. We have assayed acid β-galactosidase, β-hexosaminidase and its isozymes hexosaminidase A and B, and arylsulfatase A in the serum of patients with progressive cerebral dysfunction and detected 18 patients with enzyme defects, thereby confirming the diagnosis of a specific type of cerebral lipidosis in these patients. The assay of serum lysosomal enzymes was of immense diagnostic use as it obviated the need for highly invasive techniques like a brain biopsy.  相似文献   

4.
Multiple myeloma is a group of B-cell disorders resulting in the secretion of a specific and unique monoclonal immunoglobulin (M-protein). Protein electrophoresis is advised whenever multiple myeloma is suspected. The monoclonal protein migrates as a single entity in the electric field and is detected by the non-specific protein stain as a more intensely stained band superimposed on the usual protein pattern. The M-protein usually migrates in the gamma or beta region of the normal protein pattern; very rarely it may appear in the α2 or even in α1 region. Here we have given an atypical case presentation where the patient with multiple myeloma presented with two M-spike one each in α2 and β-globulin region on agarose gel protein electrophoresis with hypoglobulinemia but with reversed A:G ratio.  相似文献   

5.
Ectodermal dysplasia (ED) is a genetic disorder affecting the skin, hair, nails, teeth and sweat glands. The clinical presentation is heterogenous; however, hypohidrotic (reduced sweat) ectodermal dysplasia (HED) being the commonest. Also known as anhidrotic ED, sweat glands are sparse or rudimentary, leading to dysregulation of body temperature and episodes of uncontrolled hyperthermia due to reduced sweating. Of the many aids to document hypohidrosis in HED, we present here the technique of pilocarpine iontophoresis to induce, collect and measure sweat. Evaluation of sweat generated (against normally obtained values) is a non-invasive alternative to establish hypohidrosis in disorders such as HED. This augments clinical decision levels to plan skin biopsy for confirmation of diagnosis and facilitates patient management and early discharge. We present two cases of HED that were primarily diagnosed with sweat gland dysplasia using pilocarpine iontophoresis, and later confirmed with skin biopsy findings.  相似文献   

6.
Apoptosis a physiological mechanism that eliminates excessive, damaged or unwanted cells, is a highly regulated pathway important for maintaining homeostasis in multicellular organisms. It can be initiated through various signals via the extrinsic pathway which involves death receptors, or via the intrinsic pathway which is initiated by intracellular damage and involves the mitochondria and release of cytochrome c from it to further activate caspases. The Bcl-2 family of proteins is situated upstream to the irreversible damage of cellular constituents and is an important checkpoint in the fate of a cell. The pro-apoptotic members, BH3 only members include BID, BAD and BIM. They directly or indirectly activate multidomain BAX/BAK that constitute the requisite gateway to the intrinsic pathway which operates at the mitochondrial surface and endoplasmic reticulum. In contrast, antiapoptotic members such as Bcl-2, Bcl-XL bind and sequester activation. Downstream of mitochondria, the apoptosome involvement is seen to generate caspase activity. Post mitochondria regulation involves IAPs, and their inhibitors. The pathogenesis of several diseases such as cancer, neurodegenerative disorders, autoimmune disorders, heart disease, infectious diseases including AIDS is closely related to aberrant apoptosis. Consequently interest has emerged in employing various the rapeutic approaches such as gene therapy, antisense therapy, recombinant biologicals, organic and combinatorial chemistry, to specifically target apoptosis signaling pathways such as death receptors FAS/TRAIL, Bcl-2, p53, IAPs, SMAC and caspases, etc. and are now advancing from preclinical to clinical phase.  相似文献   

7.
Loss-of-function mutations in sorting nexin 14 (SNX14) cause autosomal recessive spinocerebellar ataxia 20, which is a form of early-onset cerebellar ataxia that lacks molecular mechanisms and mouse models. We generated Snx14-deficient mouse models and observed severe motor deficits and cell-autonomous Purkinje cell degeneration. SNX14 deficiency disrupted microtubule organization and mitochondrial transport in axons by destabilizing the microtubule-severing enzyme spastin, which is implicated in dominant hereditary spastic paraplegia with cerebellar ataxia, and compromised axonal integrity and mitochondrial function. Axonal transport disruption and mitochondrial dysfunction further led to degeneration of high-energy-demanding Purkinje cells, which resulted in the pathogenesis of cerebellar ataxia. The antiepileptic drug valproate ameliorated motor deficits and cerebellar degeneration in Snx14-deficient mice via the restoration of mitochondrial transport and function in Purkinje cells. Our study revealed an unprecedented role for SNX14-dependent axonal transport in cerebellar ataxia, demonstrated the convergence of SNX14 and spastin in mitochondrial dysfunction, and suggested valproate as a potential therapeutic agent.  相似文献   

8.
Mucopolysaccharidoses, a group of inherited disorders are associated with defects in glycosaminoglycan metabolism. Thus, assessment of urinary glycosaminoglycan is used as a screening test for mucopolysaccharidoses. The detection methods range from qualitative spot tests to quantification using metachromatic dyes. In our laboratory we optimized a spectrophotometric quantitative method using a metachromatic dye, dimethylmethylene blue. Heparan sulfate was used for quantification. The glycosaminoglycan–dye complex showed a marked shift in color with increase in concentration. The color complex was quantified at 520 nm. The method was linear from 10–89 mg/L. An age matched normal range was obtained in 177 healthy individuals, grouped in 8 different age groups from neonates to adults. Urinary glycosaminoglycan concentration varied distinctly amongst the study population wherein the lowest range in healthy neonates was more than 3 times the upper limit of healthy adults. Urine samples from 10 patients with mucopolysaccharidoses were also included in the study for clinical validation. The method qualified both analytical and clinical validation and was found to be simple, robust and ideal to be offered as a screening test for mucopplysaccharidoses in a routine clinical chemistry laboratory.  相似文献   

9.
Iron is an essential nutrient for a number of cellular activities. However, excess cellular iron can be toxic by producing reactive oxygen species (ROS) such as superoxide anion (O2−) and hydroxyl radical (HO·) that damage proteins, lipids and DNA. Mutagenic and genotoxic end products of lipid peroxidation can induce the decline of mitochondrial respiration and are associated with various human ailments including aging, neurodegenerative disorders, cancer etc. Zingiber officinale Roscoe (ginger) is a widely used spice around the world. The protective effect of aqueous ethanol extract of Z. officinale against ROS-induced in vitro lipid peroxidation and DNA damage was evaluated in this study. The lipid peroxidation was induced by hydroxyl radical generated from Fenton’s reaction in rat liver and brain homogenates and mitochondrial fraction (isolated from rat liver). The DNA protection was evaluated using H2O2-induced changes in pBR-322 plasmid and Fenton reaction-induced DNA fragmentation in rat liver. The results indicated that Z. officinale significantly (P<0.001) protected the lipid peroxidation in all the tissue homogenate/mitochondria. The extract at 2 and 0.5 mg/ml could protect 92 % of the lipid peroxidation in brain homogenate and liver mitochondria respectively. The percent inhibition of lipid peroxidation at 1mg/ml of Z. officinale in the liver homogenate was 94 %. However, the extract could partially alleviate the DNA damage. The protective mechanism can be correlated to the radical scavenging property of Z. officinale. The results of the study suggest the possible nutraceutical role of Z. officinale against the oxidative stress induced human ailments.  相似文献   

10.
目的:通过对南充综合医院门诊病人的抑郁障碍和焦虑障碍的发生率及共病现象研究,提高焦虑障碍与抑郁障碍的识别率。方法:随机抽取1000例门诊患者进行焦虑自评量表(SAS)和抑郁自评量表(SDS)的问卷调查,通过数据统计分析,阳性筛查焦虑障碍和抑郁障碍的患病情况。结果:门诊中有8.56%的患者存在焦虑障碍,6.03%的患者存在抑郁障碍,2.96%的患者存在焦虑障碍与抑郁障碍共病现象。女性焦虑障碍患病率大于男性患病率,女性抑郁障碍患病率大于男性患病率。结论:综合医院提高焦虑障碍与抑郁障碍的识别率的过程中应注意性别的影响,加强综合门诊对焦虑障碍及抑郁障碍的识别率。  相似文献   

11.
We investigate two fundamental research questions related to the funding of early-stage technology enterprises. First, does presentation design, and the presenting entrepreneur's passion and preparedness, influence experts' assessment of the merit and commercialization potential of an emerging firm's technology? Second, are the entrepreneur's passion and preparedness during a formal presentation associated with future technology success? We analyze twenty-two video-taped presentations to a U.S. Department of Defense technology transfer and granting consortium, and track subsequent technology success. From the data it appears that both entrepreneurial passion and presentation design does influence expert assessment of a technology, and future commercialization success can be predicted to some extent by the level of entrepreneurial passion exhibited during the presentation.  相似文献   

12.
李梅芳 《科技通报》1999,15(6):482-483
臀位是产科最常见的异常胎位之一,围产儿死亡率明显高于头位。目前经适当放宽剖宫产指征,使臀位分娩的死亡率明显降低。  相似文献   

13.
钢闸门设计缺陷形成的因素错综复杂,对设计缺陷的控制也是项复杂的工作。本文在研究其设计缺陷形成机理的基础上,应用模糊决策理论分析了设计评审点的设置,并对设计缺陷形成因素重要度进行评估,提出了在模糊约束下设计缺陷的最优解决模型。最后以某一闸门设计缺陷解决过程为实例进行说明。  相似文献   

14.
赖贇 《中国科技信息》2011,(13):102-103
汕尾电厂在建4号锅炉水冷壁集箱短管内壁发现疑似裂纹的线性缺陷。通过对样管进行化学成分分析、内壁显微观察、制管工艺分析确定了线性缺陷的成因：该线性缺陷为钢管轧制过程中产生的原始缺陷,属非裂纹性缺陷。而对样管进行压扁试验表明：该线性缺陷会随管子的压扁而扩展,从而推断在运行时缺口部位应力会较为集中,可能会造成管子提前失效爆管的后果。  相似文献   

15.
Neural tube defects are congenital structural abnormalities of the brain and vertebral column resulting from improper or non-timely closure of the neural tube. Prevalence of neural tube defects is reported to be higher among women with diabetes mellitus and obesity. This study was designed to investigate the relation between the presence of dyslipidemia in antenatal patients and the risk of fetal neural tube defects. The present study was an observational, cross-sectional study involving 129 pregnant women in 16 to 18 weeks gestation period. Of these, 80 women had normal pregnancies and 49 were clinically high-risk cases for neural tube defects. Fasting blood samples were analyzed for blood sugar and lipid profile by enzymatic assay and alpha-fetoprotein levels using Enzyme Immunoassay. Alpha-fetoprotein (AFP) values were converted to Multiples of Median (MoM) appropriate for the gestational age. Based on AFP values, women were labeled as screen negative (AFP <2 MoM, n= 102) and screen positive (AFP > 2 MoM, n =27). Screen positive women were further evaluated by ultrasound and 21 women were found to carry a neural tube defects positive pregnancy. Statistical analysis was done on SPSS software. Body weight of the women showed a significant positive correlation with serum triglycerides, plasma sugar and AFP MoM values. A significant difference was observed in serum cholesterol levels (p= 0.038), triglycerides (p=0.001) and plasma sugar levels (p=0.002) between normal women and those with neural tube defects positive pregnancy. The Odds ratio for neural tube defects risk in dyslipidemic cases was 24.23 (CI 4.73 − 148.60) with a relative risk of 12.12. Dyslipidemia especially hypertriglyceridemia was found to be significantly associated with fetal neural tube defects.  相似文献   

16.
知识表示与检索语言的关系   总被引：1，自引：0，他引：1  
吴小红 《情报科学》1994,15(2):21-24,11
本文探讨了检索语言与自然语言、人工智能及心理学研究中的知识表示的内在联系。从知识表示的角度,分析了检索语言中的语义关系与句法内容,并讨论了检索语言现有的知识表示水平对于检索效率的具体影响。  相似文献   

17.
Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme of folate pathway and required for DNA synthesis and methylation. MTHFE C677T polymorphisms is reported as risk factors for various diseases and disorders like birth defects, metabolic, neurological, psychiatric disorders, and cancers. Several studies have investigated association between the MTHFR C677T polymorphism and male infertility. To assess the risk associated with MTHFR C677T polymorphism in Asian population, a meta-analysis was performed. Included articles were collected from the following electronic databases: PubMed, Google Scholar, and Science direct up to March 2015. Risk was estimated as pooled odds ratios (ORs) with confidence intervals (CIs) for assessment. Seventeen case–control studies involving 4392 breast infertile males and 3667 fertile males were found suitable for the inclusion in the present meta-analysis. Results showed that the C677T polymorphism was significantly associated with male infertility in Asian population using all the five genetic models (ORT vs. C (allele contrast model) = 1.86, 95% CI 1.7–2.0; ORTT vs. CC (homozygote model) = 1.96, 95% CI 1.67–2.30; ORCT vs. CC (co-dominant model) = 1.40, 95% CI 1.18–1.62; ORTT+CT vs. CC (dominant model) = 1.53, 95% CI 1.30–1.77; ORTT vs. CT+CC (recessive model) = 1.67, 95% CI 1.44–1.92). In conclusion, results of present meta-analysis strongly supported an association between C677T polymorphism and male infertility in Asians.  相似文献   

18.
Lead is found in small but appreciable quantities in air, soil drinking water and food. Exposure to such amounts of lead does not cause acute lead toxicity, but produces subtle effects, particularly in children. The CDC advocates “safe” or “acceptable” levels of blood lead up to 10 μg/dl, while OSHA declares blood lead levels up to 40 μg/dl as “safe” or “acceptable” in the occupationally exposed. The objective of the study was to see if blood levels considered “safe” can cause changes in the biogenic neurotransmitters in the developing brain which may cause neurobehavioral defects like hyperactivity and other cognitive disorders. Albino Wistar rats were divided into the control and lead-treated groups. The control group was given unleaded water, while the lead-treated group was fed with 50 ppm lead acetate in drinking water. On day 45 the animals were subjected to a passive avoidance test, their blood analysed for ZPP and lead. They were then sacrificed and the neurotransmitters—Norepinephrine (NE) and its metabolite—methoxyhydroxyphenylglycol (MHPG) estimated in the brain areas associated with learning and memory—the frontal cortex, hippocampus and the striatum by HPLC-ECD. Our results showed significant increases in blood lead, NE and MHPG, while ZPP increase was insignificant. The rats showed neurobehavioral abnormalities as assessed by the passive avoidance test. We concluded that low blood levels of lead cannot be considered “safe” or “acceptable” as it causes neurotransmitter alterations. Increased NE turnover is implicated in hyperactivity disorders such as ADHD and Tourette syndrome.  相似文献   

19.
The role of bisphenol A (BPA) in autism was investigated in 49 children (mean age = 5.950 ± 1.911 years) with autism spectrum disorders (ASDs) and 40 comparable age and sex matched children used as controls (mean age = 5.333 ± 2.279 years). In addition, 8-Hydroxydeoxyguanosine (8-oxodG) was also studied as a biomarker of oxidative stress in the same set of two selected groups. The results showed that both BPA and 8-oxodG were significantly higher in children with autism than those of control children (p values = 0.025 and 0.0001, respectively). There were positive correlations between both BPA and 8-oxodG with ASDs severity (r = 0.400 and 0.805, respectively), these correlations were highly significant (p values = 0.004 and 0.001, respectively). There was a significance positive correlation between BMI and BPA, but the correlation between BMI and 8-oxodG was not significant in children with autism. The observed results revealed that BPA may increase oxidative stress resulting in mitochondrial dysfunction that affecting the behavior and functioning of ASDs children.  相似文献   

20.
徐红琴  吴泽生 《科教文汇》2013,(3):105-105,110
体育教育专业说课是提高学生课堂教学设计能力、语言表达能力、思维能力等多种教学必备能力的一种直接、有效、实用的手段。但在说课技能实践中大部分学生在内容方面存在这样或那样的问题,笔者通过对具体的技能训练中学生存在的问题进分析研究,并提出应通过指导教师和学生两方面的共同努力才能切实提高说课训练的效果。  相似文献   

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