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Purpose: This study aimed to assess vascular endothelial function in patients with ocular hypertension (OHT) or primary open‐angle glaucoma (POAG) by measuring: (a) endothelium‐dependent flow‐mediated vasodilation (FMD) of the brachial artery, and (b) circulating endothelial progenitor cells, which are believed to support the integrity of the vascular endothelium. Methods: We enrolled 25 patients with OHT, 23 with POAG and 26 control subjects, all of whom were aged < 65 years and had no medical history of cardiovascular disease or cardiovascular risk factors. All subjects underwent a complete ophthalmological examination, biochemistry study, assessment of cardiovascular parameters, brachial artery ultrasound assessment of endothelium‐dependent FMD, generic circulating progenitor cell (CPC) and circulating endothelial progenitor cell (EPC) count with the use of flow cytometry. Results: Flow‐mediated vasodilation values differed significantly in OHT (4.5 ± 1.1%; p = 0.021) and POAG (4.0 ± 0.9%; p = 0.003) patients compared with controls (7.7 ± 0.8%). The CD34+ KDR+ EPC count was markedly lower in OHT (28.0 ± 5.0; p < 0.001) and POAG (24.3 ± 3.4; p < 0.001) patients compared with controls (73.1 ± 8.1). Neither FMD not EPCs differed significantly between OHT and POAG patients. No significant differences in CPC count or cardiovascular parameters were found among OHT or POAG patients and controls. The levels of CD34+ KDR+ EPCs were directly correlated (p = 0.043) with FMD, and inversely correlated (p = 0.032) with baseline intraocular pressure in OHT and POAG patients. Conclusions: Both OHT and POAG patients without cardiovascular risk factors have previously unreported severely reduced circulating EPCs and reduced FMD, both of which are indicators of endothelial dysfunction and increased risk of cardiovascular events.  相似文献   
83.
We describe a new approach to investigate alterations in the human MLH1 mismatch repair (MMR) gene. This is based on complementation of the phenotype of a MLH1-defective subclone of the ovarian carcinoma A2780 cells by transfection of vectors encoding altered MLH1 proteins. Measurements of resistance (tolerance) to methylating agents, mutation rate at HPRT, microsatellite instability (MSI), and steady-state levels of DNA 8-oxoguanine were used to define the MMR status of transfected clones. The approach was validated by transfecting cDNA of wild-type (WT) MLH1, cDNAs bearing two previously identified polymorphisms (I219V and I219L) and two with confirmed hereditary nonpolyposis colorectal cancer (HNPCC) syndrome mutations (G224D and G67R). A low-level expression of two MLH1 polymorphisms partially reversed methylation tolerance and the mutator phenotype, including MSI. Higher levels of I219V resulted in full restoration of these properties to WT. Increased expression of I129L did not fully complement the MLH1 defect, because there was a simultaneous escalation in the level of oxidative DNA damage. The findings confirmed the important relationship between deficient MMR and increased levels of oxidative DNA damage. Mutations from Italian HNPCC families (G224D, G67R, N635S, and K618A) were all ineffective at reversing the phenotype of the MLH1-defective A2780 cells. One (K618A) was identified as a low penetrance mutation based on clinical and genetic observations.  相似文献   
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This research studied, 25 adult patients who underwent physical therapy to assess the analgesic effect of distraction with the use of music during physical therapy. Patients randomly underwent physical therapy once with music provided by an iPod and once without music. In both sessions patients underwent identical physical procedures. At end of both sessions patients filled in 5-item questionnaire where they scored pain and other parameters, such as stress, enjoyment, interaction, and satisfaction, on 10-cm visual analog scale. The mean scores (range, 0-10) of the two sessions were statistically compared. Mean pain scores were significantly lower (p = .031) during the session in which patients received music (4.8 ± 2.5) than during the session without music (5.8 ± 2.3). The other items of the questionnaire did not disclose any statistically significant difference when the sessions with versus without music were compared. Enjoyment (8.5 ± 1.6), interaction (8.3 ± 1.9), and satisfaction (8.6 ± 1.7) scores with music did not significantly differ in the sessions without music (8.5 ± 2.1, 8.5 ± 1.9, and, 8.5 ± 1.5, respectively); mean stress score was, 3.9 in both sessions. The conclusion of the study is that music provided through a portable media player has an analgesic effect. This can be an effective analgesic strategy during painful physical therapy.  相似文献   
86.
Interhemispheric interactions in stroke patients are frequently characterized by abnormalities, in terms of balance and inhibition. Previous results showed an impressive variability, mostly given to the instability of motor‐evoked potentials when evoked from the affected hemisphere. We aim to find reliable interhemispheric measures in stroke patients with a not‐evocable motor‐evoked potential from the affected hemisphere, by combining transcranial magnetic stimulation (TMS) and electroencephalography. Ninteen stroke patients (seven females; 61.26 ± 9.8 years) were studied for 6 months after a first‐ever stroke in the middle cerebral artery territory. Patients underwent four evaluations: clinical, cortical, corticospinal, and structural. To test the reliability of our measures, the evaluations were repeated after 3 weeks. To test the sensitivity, 14 age‐matched healthy controls were compared to stroke patients. In stroke patients, stimulation of the affected hemisphere did not result in any inhibition onto the unaffected. The stimulation of the unaffected hemisphere revealed a preservation of the inhibition mechanism onto the affected. This resulted in a remarkable interhemispheric imbalance, whereas this mechanism was steadily symmetric in healthy controls. This result was stable when cortical evaluation was repeated after 3 weeks. Importantly, patients with a better recovery of the affected hand strength were the ones with a more stable interhemispheric balance. Finally, we found an association between microstructural integrity of callosal fibers, suppression of interhemispheric TMS‐evoked activity and interhemispheric connectivity. We provide direct and sensitive cortical measures of interhemispheric imbalance in stroke patients. These measures offer a reliable means of distinguishing healthy and pathological interhemispheric dynamics.  相似文献   
87.
Fatty acids play an important role in regulating insulin secretion, but the mechanisms are unclear. We report a case of a novel splice site mutation in the short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) gene associated with hyperinsulinism. This mutation resulted in a nearly complete absence of immunoreactive protein and a decrease in fibroblast SCHAD activity.  相似文献   
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Deregulated signalling through phosphatidylinositol 3‐kinase (PI3K) pathway plays a critical role in tumour initiation and progression. We have already shown that AKT is activated in skin lesions in Mycosis Fungoides (MF) and we herein further investigate the frequency and clinical significance of PTEN and PI3K at the protein and at the DNA level as well as the presence of AKT1 mutations in skin lesions from 50 patients with MF clinical stages I‐IV in relation to clinicopathological features. Increased p‐AKT expression correlated with poor prognosis in plaques (P = 0.0198), whereas p‐AKT was an independent predictor of poor survival in the entire cohort (P = 0.017, HR = 1.012). PTEN cytoplasmic expression was found low or absent in all 77.3% of cases and inversely correlated with advanced clinical stages (P = 0.0744). Molecular analysis showed no AKT1 mutation, no PI3KCA copy number gain, only 1 case with PI3KCA mutation in exon 9 and 3 cases with PTEN mutations (7%) in exons 7, 8 and 5. The latter correlated with disease (P = 0.0253) and progression (P < 0.0001) free survival in tumour stage. Although activation of PI3K/AKT signalling pathway due to PTEN alterations is rarely attributed to abnormalities in PTEN, PI3K, and AKT1 genes, PTEN mutations exert a negative effect on patients’ prognosis with tumours.  相似文献   
90.
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