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71.
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease.  相似文献   
72.
The IrbesartaN/hydroChlorothiazide (HCTZ) bLood pressUre reductionS In diVErse patient populations (INCLUSIVE) trial was a multicenter, prospective, open-label, single-arm study evaluating the efficacy and safety of irbesartan/HCTZ fixed combinations in patients > or = 18 years old with uncontrolled systolic blood pressure (SBP, 140-159 mmHg; 130-159 mmHg for type-2 diabetes mellitus patients) after > or = 4 weeks of antihypertensive monotherapy. This analysis focused on different racial/ethnic subgroups. Treatment was sequential: placebo (4-5 weeks), HCTZ 12.5 mg (two weeks), irbesartan/HCTZ 150/12.5 mg (eight weeks) and irbesartan/HCTZ 300/25 mg (eight weeks). Overall, 515 Caucasians, 191 African Americans and 119 Hispanics/Latinos completing placebo treatment were enrolled. Mean SBP changes from baseline (placebo treatment end) to week 18 were -21.5 +/- 13.8 mmHg for Caucasians, -20.7 +/- 16.5 mmHg for African Americans and -22.9 +/- 13.2 mmHg for Hispanics/Latinos, respectively (p<0.001 for each). Mean diastolic BP (DBP) changes were statistically significant (p<0.001) and similar among racial/ethnic subgroups. By week 18, 70% (95% CI, 66%, 74%) of Caucasian, 66% (95% CI, 59%, 74%) of African-American and 65% (95% CI, 57%, 74%) of Hispanic/Latino patients achieved dual SBP/DBP goal. Treatments appeared to be well tolerated. In conclusion, irbesartan/HCTZ treatment provided SBP/DBP goal attainment in approximately two-thirds of Caucasian, African-American and Hispanic/Latino patients with SBP uncontrolled on antihypertensive monotherapy.  相似文献   
73.
Mitochondrial dysfunction has been implicated in the development and progression of multiple sclerosis (MS) lesions. Mitochondrial alterations might occur as a response to demyelination and inflammation, since demyelination leads to an increased energy demand in axons and could thereby affect the number, distribution and activity of mitochondria. We have studied the expression of mitochondrial proteins and mitochondrial enzyme activity in active demyelinating and chronic inactive MS lesions. Mitochondrial protein expression and enzyme activity in active and chronic inactive MS lesions was investigated using (immuno)histochemical and biochemical techniques. The number of mitochondria and their co‐localization with axons and astrocytes within MS lesions and adjacent normal‐appearing white matter (NAWM) was quantitatively assessed. In both active and inactive lesions we observed an increase in mitochondrial protein expression as well as a significant increase in the number of mitochondria. Mitochondrial density in axons and astrocytes was significantly enhanced in active lesions compared to adjacent NAWM, whereas a trend was observed in inactive lesions. Complex IV activity was strikingly up‐regulated in MS lesions compared to control white matter and, to a lesser extent, NAWM. Finally, we demonstrated increased immunoreactivity of the mitochondrial stress protein mtHSP70 in MS lesions, particularly in astrocytes and axons. Our data indicate the occurrence of severe mitochondrial alterations in MS lesions, which coincides with enhanced mitochondrial oxidative stress. Together, these findings support a mechanism whereby enhanced density of mitochondria in MS lesions might contribute to the formation of free radicals and subsequent tissue damage. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
74.
75.
Partial monosomy of the q2 region of chromosome 15 has been infrequently reported. Moreover, interstitial deletions involving 15q22-q24 have been described in only nine patients to date. The phenotype of these reported individuals is subject to the extent of the deletion but typically includes altered muscle tone and significant developmental delays. In addition, eye abnormalities, such as strabismus, microphthalmia, or colobomas, ear abnormalities including cleft earlobe and preauricular tags, and urogenital defects are common features. Congenital heart defects, diaphragmatic hernia, abnormalities of the central nervous system, and skeletal anomalies have been reported but appear to be less frequent clinical manifestations. In this report, we describe three new patients with interstitial deletions involving 15q24, two with cryptic deletions identified by fluorescence in situ hybridization (FISH) with a probe for the PML gene and one with a cytogenetically visible deletion of 15q22.3-q24. The clinical presentation of these individuals is similar to those previously described and includes global developmental delays, hypotonia, and genital abnormalities in the males. The identification of these three cases demonstrates that the above clinical features are associated with a new cytogenetic deletion syndrome. Furthermore, we suggest that FISH analysis with a probe for the PML gene be performed in patients with these physical findings.  相似文献   
76.
It has previously been shown that, in the heterozygous state, mutations in the SOX9 gene cause campomelic dysplasia (CD) and the often associated autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one recurrent mutation were characterized in one SOX9 allele each, and in one case, no mutation was found. Four missense mutations are all located within the high mobility group (HMG) domain. They either reduce or abolish the DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense and three frameshift mutations identified, two leave the C-terminal transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or almost completely intact. When tested in cell transfection experiments, the recurrent nonsense mutation Y440X, found in two patients who survived for four and more than 9 years, respectively, exhibits some residual transactivation ability. In contrast, a frameshift mutation extending the protein by 70 residues at codon 507, found in a patient who died shortly after birth, showed no transactivation. This is apparently due to instability of the mutant SOX9 protein as demonstrated by Western blotting. Amino acid substitutions and nonsense mutations are found in patients with and without XY sex reversal, indicating that sex reversal in CD is subject to variable penetrance. Finally, none of 18 female patients with XY gonadal dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP assays, providing evidence that SOX9 mutations do not usually result in XY sex reversal without skeletal malformations.   相似文献   
77.
There is now good evidence that cytokines contribute to the regulation of tumor growth. The cytokine-driven modulation of tumor growth was investigated during the progression of a hepatocellular carcinoma (HCC) in SV40 large T tumor antigen transgenic mice. In vivo, an increased rate of liver growth correlated with increased transforming growth factor (TGF)-beta 1 mRNA expression, while the greatest amounts of tumor necrosis factor (TNF)-alpha mRNA were detected earlier during tumor development. Conversely, no particular alteration of IL-1 alpha, IL-1 beta, IL-6, IL-2, IL-4 and IFN-gamma mRNA production could be reported. In vitro, hepatocyte-like tumor cell lines established at two stages, either before or after HCC differentiation, were characterized. The early-stage-derived cell line produced TNF-alpha mRNA, but had barely detectable expression of TGF-beta 1 mRNA, while later-stage- derived cell lines showed the reciprocal pattern. All cell lines displayed a lack of sensitivity to TNF-alpha, although some degree of sensitivity to TNF-alpha could be observed in the presence of actinomycin-D or after treatment with IFN-gamma. The early-stage- derived cell line was sensitive to the growth inhibitory effects of TGF- beta 1, but late-stage-derived tumor cell lines displayed a loss of sensitivity to TGF-beta 1 which correlated with the increased expression of TGF-beta 1 mRNA. Altogether, this suggests that tumor cells contribute to the discrete TNF-alpha and TGF-beta 1 expression patterns during HCC progression. This model of HCC could be of valuable interest to assess the impact of various immunotherapeutic strategies on modulation of tumor growth.   相似文献   
78.

Background  

Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population.  相似文献   
79.
IntroductionWomen with diabetes experience diminished genital arousal, reduced vaginal lubrication, vaginal atrophy, dyspareunia, and increased infections. Limited studies are available investigating the effects of diabetic complications on the vagina.AimsThe goals of this study were to investigate type 2 diabetes-induced changes in vaginal structure, and to determine if estradiol treatment ameliorates these changes.MethodsEight-week-old female diabetic (db/db) mice (strain BKS.Cg-m+/+Leprdb/J) and age-matched control normoglycemic female littermates were used to investigate the effects of type 2 diabetes on vaginal tissue structural integrity. Diabetic animals were divided into two subgroups: diabetic treated with vehicle only and diabetic treated with pellets containing estradiol. At 16 weeks, the animals were sacrificed, and the vaginal tissues were excised and analyzed by histological and immunohistochemical methods to assess diabetes-induced changes in vaginal tissue and the extent by which these parameters are restored by estradiol treatment.Main Outcome MeasuresThe effects of type 2 diabetes and estradiol supplementation were investigated on vaginal histoarchitecture.ResultsDiabetic animals exhibited high blood glucose levels (>600 mg/dL), increased body weight (43.0 ± 6.0 g vs. 24.4 ± 2.0 g), and reduced plasma estradiol levels (65.5 ± 6.6 pg/mL vs. 80.77 ± 13.2 pg/mL) when compared to control animals. Diabetes resulted in significant thinning of the epithelium (P ≤ 0.05), marked decrease in the muscularis area (P ≤ 0.05), distinct truncation of elastic fibers, and significant reduction of the nitrergic immunoreactive nerve fibers (P ≤ 0.05). Treatment of diabetic animals with estradiol restored epithelial thickness (P ≤ 0.05), muscularis area (P ≤ 0.05), and elastic fiber distribution, and partially restored the density of nitrergic nerve fibers.ConclusionsThe data in this study demonstrate that type 2 diabetes disrupts vaginal structural integrity and that estradiol supplementation ameliorates the diabetes-induced vaginal pathology. Cushman TT, Kim N, Hoyt R, and Traish A. Estradiol ameliorates diabetes-induced changes in vaginal structure of db/db mouse model. J Sex Med 2009;6:2467–2479.  相似文献   
80.
To examine the associations of three understudied hemostatic factors—D‐dimer, factor VIIIc, and plasmin‐antiplasmin (PAP) complex—with incident cardiovascular disease (CVD) and all cause mortality in the Multiethnic Study of Atherosclerosis cohort. Hemostatic factors were measured at baseline in 45–84‐year‐old patients (n = 6,391) who were free of clinically recognized CVD. Over 4.6 years of follow‐up, we identified 307 CVD events, 207 hard coronary heart disease events, and 210 deaths. D‐dimer, factor VIIIc, and PAP were not associated with CVD incidence after adjustment for other risk factors. In contrast, each factor was associated positively with total mortality, and D‐dimer and factor VIIIc were associated positively with cancer mortality. When modeled as ordinal variables and adjusted for risk factors, total mortality was greater by 33% (95% CI 15–54) for each quartile increment of D‐dimer, 26% (11–44) for factor VIIIc, and 20% (4–38) for PAP. This prospective cohort study did not find D‐dimer, factor VIIIc, or PAP to be risk factors for CVD. Instead, elevated levels of these three hemostatic factors were associated independently with increased risk of death. Elevated D‐dimer and factor VIIIc were associated with increased cancer death. Am. J. Hematol., 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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