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81.
ObjectiveWe tested the hypotheses that monthly fluctuations in markers of arterial stiffness and blood pressure hemodynamics differ between women with and without premenstrual syndrome. We also assessed hypertension prevalence and arterial stiffening in postmenopausal women with or without history of premenstrual symptoms.MethodsTwenty one pre-menopausal women with premenstrual syndrome and 15 women without were prospectively examined in three distinct phases of their menstrual cycle (menses, late follicular and luteal phase). Pulse-wave velocity and analysis were used to assess arterial stiffness and wave reflection indices, respectively. Endothelial function was evaluated by flow-mediated vasodilation. In a cross-sectional substudy, 156 postmenopausal women were assessed for possible associations between retrospectively reported PMS symptoms and hypertension.ResultsIn women with premenstrual syndrome, arterial stiffness significantly increased during the luteal and menses phase (late follicular: 6.48 ± 1.07, luteal: 7.1 ± 1.26, menstruation: 7.12 ± 1.19 m/s, p = 0.003), while blood pressure peaked at the menses phase. Significant interactions between PMS and changes in arterial stiffness and blood pressure but not endothelial function, were observed. Changes in PWV were significantly associated with concomitant changes in blood pressure, C-reactive protein and the severity of PMS symptoms. The prevalence of hypertension (20.9% vs. 40.9%, p = 0.041) and pulse-wave velocity values (8.64 ± 1.52 vs. 9.37 ± 1.1, p = 0.046) were higher in postmenopausal women with 7 or more reported PMS symptoms. Arterial stiffness differences remained significant after adjustment for confounding factors.ConclusionThese results imply that PMS may affect arterial stiffness and BP monthly variability. Whether PMS is associated with new onset hypertension later in life needs further evaluation.  相似文献   
82.
The heptameric mechanosensitive channel of small conductance (MscS) provides a critical function in Escherichia coli where it opens in response to increased bilayer tension. Three approaches have defined different closed and open structures of the channel, resulting in mutually incompatible models of gating. We have attached spin labels to cysteine mutants on key secondary structural elements specifically chosen to discriminate between the competing models. The resulting pulsed electron–electron double resonance (PELDOR) spectra matched predicted distance distributions for the open crystal structure of MscS. The fit for the predictions by structural models of MscS derived by other techniques was not convincing. The assignment of MscS as open in detergent by PELDOR was unexpected but is supported by two crystal structures of spin-labeled MscS. PELDOR is therefore shown to be a powerful experimental tool to interrogate the conformation of transmembrane regions of integral membrane proteins.  相似文献   
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Coenzyme Q10 (CoQ10) deficiency has been proposed to be causal in 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitor (statin)-induced myopathies. However, the clinical benefit of supplementation is unproved. The purpose of the present study was to assess the effect of CoQ10 supplementation on myalgias presumed to be caused by statins. Patients currently receiving a statin who developed new-onset myalgias in ≥ 2 extremities within 60 days of initiation or a dosage increase were eligible. Patients continued statin therapy and were randomized using a matched design to either CoQ10 60 mg twice daily or matching placebo. Double-blind treatment continued for 3 months, and patients completed a 10-cm visual analog scale (VAS) and the Short-Form McGill Pain Questionnaire at baseline and at each monthly visit. The primary end point was the comparison of the VAS score at 1 month. A total of 76 patients were enrolled (40 in the CoQ10 arm and 36 in the placebo arm). The mean VAS score was 6 cm at baseline in both groups. At 1 month, no difference was seen in the mean VAS score between the 2 groups (3.9 cm in the CoQ10 group and 4 cm in the placebo group; p = 0.97). However, 5 patients in the CoQ10 group and 3 in the placebo group discontinued therapy during the first month because of myalgias. The baseline median score on the Sensory Pain Rating Index subscale was 10 in the CoQ10 group and 11.5 in the placebo group. At 1 month, these scores had decreased to 6.5 and 7.5, respectively, with no statistically significant difference (p = 0.34). In conclusion, CoQ10 did not produce a greater response than placebo in the treatment of presumed statin-induced myalgias.  相似文献   
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J Oral Pathol Med (2012) 41 : 40–46 Background: The purpose of this study was to evaluate whether the immunohistochemical expression of p53, p21, p27, cyclin D1, and Ki67 can predict therapy response and survival in patients with oral and oropharyngeal squamous cell carcinoma treated with preoperative chemoradiation. Methods: Biomarker expression was evaluated by immunohistochemistry in formalin‐fixed, paraffin‐embedded pretreatment biopsies of 111 homogenously treated patients. We assessed the association between clinicopathological variables including response to neoadjuvant chemoradiotherapy as well as the survival of the patients and the expression of the biomarkers as both dichotomized (positive vs. negative) and continuous variables. Results: Biomarker overexpression on the basis of pre‐selected cutoff points was seen in 66 of 111 (59%) cases for p53, in 77 (69%) for p21, in 48 (43%) for p27, in 81 (73%) for cyclin D1, and in 54 (49%) cases for Ki67, respectively. None of the examined biomarkers was able to predict response to neoadjuvant chemoradiotherapy or was associated with survival outcome. Post‐treatment pathologic TNM stage (P < 0.001), pathologic response (P < 0.001), and perineural invasion (P < 0.001) were the only factors having a significant effect on recurrence‐free survival. Post‐treatment pathologic N stage (P = 0.005), post‐treatment pathologic TNM stage (P < 0.001), pathologic response (P < 0.001), and perineural invasion (P = 0.001) had a significant impact on overall survival. Conclusions: Our results suggest that the biomarkers p53, p21, p27, cyclin D1, and Ki67 have no impact on treatment response and survival in patients with oral and oropharyngeal cancer treated with preoperative chemoradiation.  相似文献   
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In this longitudinal study, the craniofacial morphology and evaluated soft tissue profile changes, at 6 and 12 years of age in patients with complete bilateral cleft lip and palate (CBCLP) were compared. Lateral cephalograms from 148 patients with CBCLP, treated consecutively at three European cleft centers, Gothenburg (n (A) = 37), Nijmegen (n (B) = 26), and Oslo (n (C) = 85), were evaluated. Eighteen hard tissue and ten soft tissue landmarks were digitized. Paired t test, Pearson's correlation coefficients, and multiple regression models were applied for statistical analysis. ANOVA and Tukey-B, as a post hoc test, were used to evaluate the increments and compare centers. Hard and soft tissue data were superimposed using the generalized Procrustes analysis. For Nijmegen, the increments of the variables SNA, ANB, SN-NL, SN-ML, NL-ML, Snss, and Snpg were significantly different than the two other centers (p = 0.041 to <0.001). SNPg increments were significantly different between Nijmegen and Oslo (p = 0.002). The three cleft centers followed different treatment protocols, but the main differences in craniofacial morphology until 12 years of age were the growth pattern and the maxillary and upper incisor variables. Follow-up of these patients until facial growth has ceased, which may elucidate components for improving treatment outcome.  相似文献   
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90.
The hydroxy-methyl-glutaryl-CoA reductase inhibitors (statins) are used extensively in the treatment for hyperlipidemia. They have also demonstrated a benefit in a variety of other disease processes, including a wide range of rheumatologic disorders. These secondary actions are known as pleiotropic effects. Our paper serves as a focused and updated discussion on the pleiotropic effects of statins in rheumatologic disorders and emphasizes the importance of randomized, placebo-controlled trials to further elucidate this interesting phenomenon.  相似文献   
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