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101.
The progressive myoclonus epilepsy of the Lafora type (LD; MIM 254780) is a rare autosomal recessive disorder characterized by epilepsy, myoclonus, progressive neurological deterioration, and the presence of periodic acid-Schiff-positive polyglucosan inclusions (Lafora bodies). Mutations in the EPM2A gene have recently been found to cause LD and about 30 or more mutations have been reported thus far. LD is relatively common in countries of the Mediterranean Basin, the Middle East, India, and Pakistan. Although a few sporadic cases with the typical LD phenotype have also been reported in the Far East including Korea and Japan, a recent effort to find mutations in Japanese LD families was not successful. In the present study, we report two novel mutations in a Korean girl with LD; a 1-bp insertion mutation (c.223insC; G75fsX107) in exon 1 and a missense mutation (c.559A>G; T187A) in exon 3 of the EPM2A gene. To our knowledge, this is the first report of a genetically confirmed case of LD in Koreans and also in the Far East.  相似文献   
102.
The aim of this study was to develop a sensitive and reliable method for the molecular identification of pathogenic bacteria. A multiplex PCR-based reverse line blot (mPCR/RLB) hybridisation assay was developed and evaluated for the rapid identification of 24 systemic and respiratory bacterial pathogens in routine diagnosis. All species-specific probes designed for the RLB hybridised with amplified DNA only from the corresponding species. Sensitivity limits of the mPCR/RLB assay varied among the 24 target organisms from 0.05 pg to 0.5 ng of genomic DNA. The sensitivity of the assay was 2 x 10(2) CFU/mL for Streptococcus pneumoniae and 6 x 10(2) CFU/mL for Escherichia coli. The specificity of each probe was tested against 24 species. There were no cross-reactions among any of the 43 probes. The mPCR/RLB assay appeared to be a useful alternative tool for the molecular identification of common pathogens.  相似文献   
103.
To determine structural features necessary for the production of direct mutagenic activity from oligoamine-nitrate reaction mixtures, we systematically tested a group of aliphatic amine substrates for comutagenic action with nitrite. The ability to react with nitrite and form direct-acting mutagenic derivatives was common to a reasonably well defined class of aliphatic polyamines. In general, primary-secondary diamino compounds were mutagenic in the Ames Salmonella tester system when reacted with nitrite, whereas primary and secondary amines produced no direct mutagenic activity when tested separately. In combination with teritary amino groups, primary amines were inactive; one secondary-tertiary amine was tested, and this substrate produced mutagenic activity.  相似文献   
104.
The incidence of obesity, which is closely associated with the gut microbiota and chronic inflammation, has rapidly increased in the past 40 years. Therefore, the probiotic-based modification of the intestinal microbiota composition has been developed as a strategy for the treatment of obesity. In this study, we selected four Bifidobacterium adolescentis strains isolated from the feces of newborn and elderly humans to investigate whether supplementation with B. adolescentis of various origins could alleviate obesity in mice. Male C57BL/6J mice fed a high-fat diet (HFD, 60% energy as fat) received one of the following 14-week interventions: (i) B. adolescentis N4_N3, (ii) B. adolescentis Z25, (iii) B. adolescentis 17_3, (iv) B. adolescentis 2016_7_2, and (v) phosphate-buffered saline. The metabolic parameters, thermogenesis, and immunity of all treated mice were measured. Cecal and colonic microbial profiles were determined by 16S rRNA gene sequencing. Intestinal concentrations of short-chain fatty acids (SCFAs) were measured by gas chromatography-mass spectrometry (GC-MS). The B. adolescentis strains isolated from the feces of elderly humans (B. adolescentis Z25, 17_3, and 2016_7_2) decreased the body weight or weight gain of mice, whilst the strain isolated from the newborn (B. adolescentis N4_N3) increased the body weight of mice. The B. adolescentis strains isolated from the elderly also increased serum leptin concentrations and induced the expression of thermogenesis- and lipid metabolism-related genes in brown adipose tissue. All the B. adolescentis strains alleviated inflammations in the spleen and brain and modified the cecal and colonic microbiota. Particularly, all strains reversed the HFD-induced depletion of Bifidobacterium and reduced the development of beta-lactam resistance. In addition, the B. adolescentis strains isolated from the elderly increased the relative abundances of potentially beneficial genera, such as Bacteroides, Parabacteroides, and Faecalibaculum. We speculate that such increased abundance of commensal bacteria may have mediated the alleviation of obesity, as B. adolescentis supplementation decreased the intestinal production of SCFAs, thereby reducing energy delivery to the host mice. Our results revealed that certain strains of B. adolescentis can alleviate obesity and modify the gut microbiota of mice. The tested strains of B. adolescentis showed different effects on lipid metabolism and immunity regulation, with these effects related to whether they had been isolated from the feces of newborn or elderly humans. This indicates that B. adolescentis from different sources may have disparate effects on host health possibly due to the transmission of origin-specific functions to the host.  相似文献   
105.
Metabolic syndrome is a worldwide health problem, and obesity is closely related to type 2 diabetes, cardiovascular disease, hypertension, and cancer. According to WHO in 2018, the prevalence of obesity in 2016 tripled compared to 1975. D. morbifera reduces bad cholesterol and triglycerides levels in the blood and provides various antioxidant nutrients and germicidal sub-stances, as well as selenium, which helps to remove active oxygen. Moreover, D. morbifera is useful for treating cardiovascular diseases, hypertension, hyperlipidemia, and diabetes. Therefore, we study in vivo efficacy of D. morbifera to investigate the prevention effect of obesity and cholesterol. The weight and body fat were effectively reduced by D. morbifera water (DLW) extract administration to high-fat diet-fed C57BL/6 mice compared to those of control mice. The group treated with DLW 500 mg∙kg−1∙d−1 had significantly lower body weights compared to the control group. In addition, High-density lipoprotein (HDL) cholesterol increased in the group treated with DLW 500 mg∙kg−1∙d−1. The effect of DLW on the serum lipid profile could be helpful to prevent obesity. DLW suppresses lipid formation in adipocytes and decreases body fat. In conclusion, DLW can be applied to develop anti-obesity functional foods and other products to reduce body fat.  相似文献   
106.
分别采用化学、声化学及光辐射等方法合成了1-丙二烯基-2,3,4,6四-氧-乙酰基-β-D-吡喃糖苷,结果表明声化学方法最有效、快速;借助电子自旋共振(ESR)技术及相关实验,证实此类糖苷的生成为一离子消除反应,所合成的糖苷化合物脱去乙酰基后对T、B淋巴细胞具有体外免疫调节作用。  相似文献   
107.
采用外耳道及鼓室再造术治疗先天性外耳道完全闭锁29例。统计各种外、中耳畸形情况,比较耳廓发育程度、颞骨相当于外耳道口处有无骨性小凹、术前听力损失程度与中耳畸形的关系,将术前的常规横断位CT检查结果与术中所见进行对照。结果显示,术前可通过耳廓发育程度、相当于外耳道口处有无骨性小凹、听力损失程度和颞骨CT扫描来综合估计中耳畸形情况,为术前了解手术难度和确定手术进路及方式提供一定的参考依据。  相似文献   
108.
109.
肾盂输尿管癌p53、nm23表达的临床意义   总被引:2,自引:0,他引:2  
目的:揭示p53、nm23基因表达与肾盂输尿管癌生物学行为的关系。方法:采用免疫组化SABC法和原位杂交技术检测p53、nm23的表达。结果:肾盂输尿管癌p53、nm23阳性表达分别为51.1%(23/45)和46.7%(21/45)。p53阳性表达T2-T3为60%(21/35),T1为20%(2/10),P<0.05;G2-G3为59.0%(23/39),G1为0%(0/6)。nm23阳性表达T2-T3为48.6%(17/35),T1为40%(4/10),P>0.05,G2-G3为48.7%(19/39),G1为33.3%(2/6),P>0.05。p53阳性表达术后再发膀胱癌与阴性表达相比较P>0.05。nm23阳性表达术后膀胱癌再发为61.9%(13/21),阴性表达为20.9%(5/24),P<0.05。p53、nm23阳性表达生存率明显低于阴性表达,P<0.05。结论:p53阳性表达与肾盂输尿管癌病理分期、分级有关,nm23阳性表达与术后再发膀胱癌有关。p53和nm23可能是判断肾盂输尿管癌预后的指标之一。  相似文献   
110.
目的 调查HIV/结核双重感染患者的营养风险及影响因素,为HIV/结核双重感染患者的营养管理提供参考.方法 采用营养风险筛查2002回顾性收集321例HIV/结核双重感染患者营养风险筛查结果,对营养风险的影响因素进行Logistic回归分析.结果 HIV/结核双重感染患者营养风险发生率为57.94%;回归分析结果显示,BMI、血红蛋白和HIV-RNA定量是HIV/结核双重感染患者营养风险的影响因素(均P<0.01).结论 HIV/结核双重感染患者营养风险比例较高,应重点关注BMI较低、贫血和HIV-RNA定量较高患者,及时纠正营养风险.  相似文献   
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