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141.
142.
Research Methods and Procedures: High‐fat (HF) diet feeding can induce obesity and metabolic disorders in rodents that resemble the human metabolic syndrome. However, this dietary intervention is not standardized, and the HF‐induced phenotype varies distinctly among different studies. The question which HF diet type is best to model the metabolic deterioration seen in human obesity remains unclear. Therefore, in this review, metabolic data obtained with different HF diet approaches are compiled. Both whole‐body and organ‐specific diet effects are analyzed. Results: On the basis of these results, we conclude that animal fats and ω‐6/ω‐9‐containing plant oils can be used to generate an obese and insulin‐resistant phenotype in rodents, whereas fish oil‐fed animals do not develop these disorders. Discussion: Looking at the present data, it does not seem possible to define an ideal HF diet, and an exact definition of diet composition and a thorough metabolic characterization of the HF diet effects in a researcher's specific laboratory setting remains essential for metabolic studies with this model.  相似文献   
143.
Objective: The diagnostic criteria and the clinical usefulness of the metabolic syndrome (MetSy) are currently questioned. The objective was to describe the structure of MetSy and to evaluate its components for prediction of diabetes type 2 (T2DM). Research Methods and Procedures: This was a case‐referent study nested within a population‐based health survey. Among 33,336 participants, we identified 177 initially non‐diabetic individuals who developed T2DM after 0.1 to 10.5 years (mean, 5.4 years), and, for each diabetes case, two referents matched for sex, age, and year of health survey. Baseline variables included oral glucose tolerance test, BMI, blood pressure, blood lipids, adipokines, inflammatory markers, insulin resistance, and β‐cell function. Exploratory and confirmative factor analyses were applied to hypothesize the structure of the MetSy. The prediction of T2DM by the different factors was evaluated by multivariate logistic regression analysis. Results: A hypothetical five‐factor model of intercorrelated composite factors was generated. The inflammation, dyslipidemia, and blood pressure factors were predicitive only in univariate analysis. In multivariable analyses, two factors independently and significantly predicted T2DM: an obesity/insulin resistance factor and a glycemia factor. The composite factors did not improve the prediction of T2DM compared with single variables. Among the original variables, fasting glucose, proinsulin, BMI, and blood pressure values were predictive of T2DM. Discussion: Our data support the concept of a MetSy, and we propose five separate clusters of components. The inflammation and dyslipidemia factors were not independently associated with diabetes risk. In contrast, obesity and accompanying insulin resistance and β‐cell decompensation seem to be two core perturbations promoting and predicting progression to T2DM.  相似文献   
144.
细胞因子在ARDS发病机制中的作用   总被引:10,自引:0,他引:10  
细胞因子是由多种细胞产生的多肽或低分子糖蛋白,在人体内含量极微,在pg水平就发挥作用。作为特异性免疫反应和非特异性免疫反应的蛋白质,细胞因子以自分泌、旁分泌、或内分泌方式产生,与相应的细胞表面受体结合,在局部或全身发挥复杂的生物学效应,它们的代谢异常和疾病的发生、发展有着密切的关系。有些细胞因子已应用于临床的生物学治疗,具有深远的临床应用价值,故对细胞因子的研究将是一个越来越重要的课题。急性肺损伤(ALI)/急性呼吸窘迫综合征(ARDS)发病机制错综复杂,大量临床和实验室研究证明多种效应细胞释放的炎症介质是造成ARDS的"中心环节",其中TNF-α、IL-1、IL-8、IL-10、CXC趋化因子等细胞因子在ARDS发病中的作用尤为重要。本文就细胞因子在ARDS发病机制中的作用做一综述。  相似文献   
145.
本文以Tusscher提出的人体心室单细胞计算模型为基础,用计算机建模仿真的方法,构建一个心室壁组织的二维网格模型。通过修改细胞的离子通道参数,仿真了正常生理条件下和Brugada症状下三类心室细胞的动作电位和心电图波形。结果显示:Brugada症状下的心电图波形有明显的J波出现,ST-段抬高甚至T波倒置。这与临床医学上的报道基本符合,本研究为用计算机仿真建模研究Brugada综合症打下了基础。  相似文献   
146.
This study identified mutations of the idumate-2-suffatase (IDS) gene in a patient with Hunter syndrome,and established a basis for the diagnosis of the prenatal gene of Hunter syndrome.Urine glyeosaminoglycan (GAG) assay was used to make the preliminary diagnosis of mucopolysaccharidosis type H.Polymerase chain reaction (PCR) from dried blood spots and DNA sequencing were applied to analyze hotspot mutations in exons 9,3 and 8 of the IDS gene in the proband and his parents.A new missense mutation (T1140C) in exon 8 of the IDS gene was found by using DNA sequencing.This mutation caused a substitution of codon 339 from CTA (leucine) to CCA (praline).The patient is a hemizygote,and his mother is a heterozygote.The new missense mutation results in a change in the primary and tertiary structure of the IDS protein.It is possible that this mutation severely impairs enzymatic activity and is the underlying basis for the pathology seen in this patient with Hunter syndrome.  相似文献   
147.
Patients with LQT syndrome are prone to lifethreatening arrhythmias. After surviving such an event, implantation of an ICD is indicated. There are, however, special subtle demands in the treatment of these patients. In this case report we describe our findings in a patient with LQT1 syndrome, and the pitfalls that can and must be avoided. (Neth Heart J 2007;15:418-21.)  相似文献   
148.
Congenital defects among liveborn infants with Down syndrome   总被引:2,自引:0,他引:2  
BACKGROUND: Many infants with Down syndrome (DS) have co-occurring congenital malformations requiring intensive surgical and medical management. To anticipate the care needed by these infants, providers and parents require accurate information about birth defects that may be present. This article uses a unique national hospital discharge dataset to identify the rate at which structural birth defects are identified among liveborn infants with DS. METHODS: ICD-9-CM diagnosis codes for data from the Healthcare Cost and Utilization Project were used to identify infants with and without DS, and to classify birth defects. The study population consisted of liveborn infants discharged from the hospital from 1993 through 2002. ORs for the association between the occurrence of congenital malformations and the presence of DS were computed using logistic regression models for survey data. RESULTS: Discharge data included 11,372 DS and 7,884,209 non-DS births, representing national estimates of 43,463 DS and 39,716,469 non-DS births respectively. In addition to congenital heart defects that co-occurred most often in DS infants compared to infants without DS, the risks for gastrointestinal malformations (OR 67.07), genitourinary malformations (OR 3.62), orofacial malformations (OR 5.63), and abdominal wall malformations (OR 3.25) were also elevated in infants with DS. There was no difference in the risk of spina bifida between infants with and without DS. CONCLUSIONS: This is the first nationally representative compilation of the co-occurrence of congenital malformations associated with DS. This information may assist providers and parents in their attempts to understand and prepare for the true burden of this condition.  相似文献   
149.
BACKGROUND: The symptom triad of autosomal dominant Currarino syndrome (CS; MIM #176450) consists of anorectal malformation, a sacral bone defect, and presacral masses. Mutations in the homeoboxHLXB9 gene have already been described in a subset of sacrococcygeal anomalies characterized by partial sacral agenesis. CASE: We report a 28-year-old male patient with Currarino syndrome due to a heterozygous novel frame-shift mutation c.336dupG (p.P113fsX224) in the homeoboxHLXB9 gene. CONCLUSIONS: Molecular diagnostics may be helpful in cases of Hirschsprung's disease accompanied by other symptoms suggestive for Currarino syndrome, since it can lead to major complications such as perianal sepsis, meningitis, and malignant transformation.  相似文献   
150.
Infections early in life can have enduring effects on an organism's development and immunity. In this study, we show that this equally applies to developing ‘superorganisms’––incipient social insect colonies. When we exposed newly mated Lasius niger ant queens to a low pathogen dose, their colonies grew more slowly than controls before winter, but reached similar sizes afterwards. Independent of exposure, queen hibernation survival improved when the ratio of pupae to workers was small. Queens that reared fewer pupae before worker emergence exhibited lower pathogen levels, indicating that high brood rearing efforts interfere with the ability of the queen's immune system to suppress pathogen proliferation. Early-life queen pathogen exposure also improved the immunocompetence of her worker offspring, as demonstrated by challenging the workers to the same pathogen a year later. Transgenerational transfer of the queen's pathogen experience to her workforce can hence durably reduce the disease susceptibility of the whole superorganism.  相似文献   
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