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101.

Introduction and hypothesis

The aim of the study was to correlate histological and biomechanical characteristics of the vaginal wall in women with pelvic organ prolapse (POP).

Methods

Tissue samples were collected from the anterior [point Ba; POP Questionnaire (POP-Q)] and/or posterior (point Bp; POP-Q) vaginal wall of 15 women who underwent vaginal surgery for POP. Both histological and biomechanical assessments were performed from the same tissue samples in 14 of 15 patients. For histological assessment, the density of collagen and elastin fibers was determined by combining high-resolution virtual imaging and computer-assisted digital image analysis. For biomechanical testing, uniaxial tension tests were performed to evaluate vaginal tissue stiffness at low (C0) and high (C1) deformation rates.

Results

Biomechanical testing highlights the hyperelastic behavior of the vaginal wall. At low strains (C0), vaginal tissue appeared stiffer when elastin density was low. We found a statistically significant inverse relationship between C0 and the elastin/collagen ratio (p?=?0.048) in the lamina propria. However, at large strain levels (C1), no clear relationship was observed between elastin density or elastin/collagen ratio and stiffness, likely reflecting the large dispersion of the mechanical behavior of the tissue samples.

Conclusion

Histological and biomechanical properties of the vaginal wall vary from patient to patient. This study suggests that elastin density deserves consideration as a relevant factor of vaginal stiffness in women with POP.
  相似文献   
102.
High degrees of premature retirement among teachers warrant investigating the occupational burden and the mental health status of this profession. A sample of 1074 German teachers participated in this study. Two samples of the general population (N = 824 and N = 792) were used as comparison groups. Work distress was assessed with the Effort–Reward‐Imbalance questionnaire, and mental health problems were measured with the General Health Questionnaire (GHQ‐12). Teachers reported more effort–reward imbalance (M = 0.64) compared with the general population (M = 0.57), and they perceived more mental health problems (GHQ: M = 12.1) than the comparison group (M = 9.5). School type was not associated with work stress and mental health. Teachers with leading functions perceived high degrees of effort and reward, resulting in a moderate effort–reward ratio and no heightened mental health problems. Teachers working full time reported more effort than teachers working part time, but the reward mean values of both groups were similar. This results in a somewhat unfavourable effort–reward ratio of teachers working full time. Moreover, teachers working full time reported more mental health problems. The results support the appropriateness of the effort–reward conception, applied to the profession of teachers. The higher degree of effort–reward imbalance and the level of mental health problems warrant preventive measures. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
103.
Abstract:  This longitudinal study assessed the influence of post-transplant clinical and therapeutic variables in 50 kidney transplant recipients aged 2–19 yr receiving a triple immunosuppressive regimen consisting of cyclosporine microemulsion (CsA), steroids and MMF (300–400 mg/m2 body surface area twice daily), the full pharmacokinetic profile (10 points) of which was investigated on post-transplant days 6, 30, 180 and 360. Total plasma MPA was measured by Enzyme Multiplied Immunoassay Technique. CsA therapeutic drug monitoring (TDM) was performed via C2 blood monitoring, while MPA TDM via C0. MPA Cmax, tmax, AUC0-12 and AUC0-4 pharmacokinetic profile changed significantly during the first post-transplant year. C0 was a poor predictor of the total MPA exposure [as measured by the area under the concentration-time curve AUC)], while a truncated AUC was a good surrogate of the 12-h profile (r = 0.91; p < 0.001) Graft function and cyclosporine therapy influenced MPA pharmacokinetics, as shown by the univariate and multivariate analyses. We conclude that because after transplantation MPA exposure varied over time, a strict TDM is advisable in the pediatric population.  相似文献   
104.
105.
Photobiomodulation is proposed as a non-linear process, and only low-level laser therapy (LLLT) is assumed to stimulate exposed cells, whereas high powered laser and fluences can cause negative effects, exhausting the cell’s energy reserve as a consequence of excessive photon-based stimulation. In our work, we investigated and compared the effects of 808-nm diode laser (CW) with a new flat-top handpiece. To this purpose, we tested the photobiomodulation effects of 1 and 3 J/cm2 fluence, both generated by 100 mW or 1 W of laser power and of 64 J/cm2 of fluence generated by 100 mW, 1 W, 1.5 W or 2 W, as expressed through oxygen consumption and ATP synthesis of Paramecium. Data collected indicates the incremental consumption of oxygen through irradiation with 3 J/cm2–100 mW or 64 J/cm2–1 W correlates with an increase in Paramecium ATP synthesis. The Paramecium respiration was inhibited by fluences 64 J/cm2–100 mW or 64 J/cm2–2 W and was followed by a decrease in the endogenous ATP concentration. The 1 J/cm2–100 mW or 1 W and 3 J/cm2–1 W did not affect mitochondrial activity. The results show that the fluence of 64 J/cm2–1 W more than the 3 J/cm2–100 mW causes greater efficiency in Paramecium mitochondria respiratory chain activity. Our results suggest that thanks to flat-top handpiece we used, high fluences by high-powered laser have to be reconsidered as an effective and non-invasive therapy. Possible associated benefits of deeper tissue penetration would increase treatment effectiveness and reduced irradiation time.  相似文献   
106.
Objectives. Carbonic anhydrase IX (CA IX) expression is induced by local hypoxia. We studied whether CA IX deposits associate with ascending aortic dilatation. Design. Aortic wall histology, CA IX expression, presence of leukocytes, plasma cells, macrophages, endothelial cells, smooth muscle cells, cell proliferation, elastin and collagen were studied in histological specimens collected from 30 patients who underwent surgery for ascending aorta. The samples were grouped according to presence of CA IX deposits. Results. Twenty out of 30 patients had CA IX-positive deposits within the adventitia, whereas 10 specimens remained negative. Adventitial inflammation was increased in CA IX-positive samples as compared with CA IX-negative ones (p?<?0.01). The mean diameter of the ascending aorta at the sinotubular junction increased significantly in patients with CA IX-positive staining as compared with CA IX-negative cases (63?±?3 vs 53?±?2?mm, p?<?0.02). Receiver operating characteristic curve analysis confirmed the association of CA IX positivity with increased ascending aortic dilatation (AUC 0.766; S.E. 0.090; p?=?0.020; 95% C.I. 0.590–0.941). Conclusions. Positive CA IX staining in certain aortic specimens suggests that increased CA activity may contribute to ascending aortic dilatation.  相似文献   
107.
Colitis cystica profunda is a rare intestinal lesion. Because of its clinical expression (rectorrhagia, mucorrhea and abdominal pain) and the way it appears to current imaging techniques this disease presents features which can be associated with colon neoplasm. Its diagnosis has to be confirmed histologically, and its etiology remains unclear. The following is a case report of colitis cystica profunda recurring 20 years after a first episode in a white woman, who had had an anterior resection of the sigmoid colon and upper rectum to deal with a colitis cystica profunda-induced stenosis of the sigmoid colon and at 41 underwent the transanal removal of a polypoid lesion. A review of 20 cases in the literature showed that colitis cystica profunda has a predilection for the male and generally affects the medial and lower rectum and the sigmoid colon. The literature also confirmed the association with ulcerative rectocolitis, Crohn's disease and rectal prolapse. The type of treatment varies from surgical, medical, and endoscopic to no treatment at all.  相似文献   
108.
Prostate cancer is the most common malignancy in males. Despite the efforts for an early diagnosis, approximately one third of the cases are diagnosed in advanced clinical stages. Prostatic cancer, as the function of normal prostate is dependent upon androgens. So, androgenic deprivation represents an effective treatment especially in advanced cases. Although, the majority of patients will initially respond to androgen blockade, consequently the hormone-resistance will develop and the tumor will progress. The mechanism that determines tumoral progression during the endocrine treatment is driven by genomic instability, characterized by activating mutations of androgen receptor gene (AR), progression of some cellular clones possible of neuroendocrine origin that become adapted to low concentrations of residual adrenal androgens, suppression of apoptosis, by bcl-2 oncogene overexpression and p53 mutations, and growth factors (IGF-1--Insulin-like growth factor, KGF--keratinocyte growth factor, EGF--Epidermal growth factor, TGF a, b- Transforming growth factor a and b, bFGF--Fibroblastic growth factor type b) regulatory effect through either a paracrine or an autocrine mechanism. The identification of molecular alterations that appear during prostate carcinogenesis, may lead to the identification of new molecular targets to prevent hormone-resistance and to improve the prognosis in prostate cancers.  相似文献   
109.
Background  It has been proposed that there is improvement in glucose and insulin metabolism after weight loss in patients who underwent diet restriction and bariatric surgery. Methods  Eleven normal glucose tolerant (NGT) morbidly obese patients [body mass index (BMI), 46.1 ± 2.27 g/m2] and eight abnormal glucose metabolism (AGM) obese patients (BMI, 51.20 kg/m2) were submitted to diet-restriction and bariatric surgery. Prospective study on weight loss changes, over the glucose, insulin metabolism, glucagon-like peptide-1 (GLP-1), and adiponectin levels were evaluated by oral glucose tolerance test during three periods: T1 (first evaluation), T2 (pre-surgery), and T3 (9 months after surgery). Results  Insulin levels improved after surgery. T1 was 131.1 ± 17.60 pmol/l in the NGT group and 197.57 ± 57.94 pmol/l in the AGM group, and T3 was 72.48 ± 3.67 pmol/l in the NGT group and 61.2 ± 9.33 pmol/l in the AGM group. The major reduction was at the first hour of the glucose load as well as fasting levels. At 9 months after surgery (T3), GLP-1 levels at 30 and 60 min had significantly increased in both groups. It was observed that the AGM group had higher levels of GLP-1 at 30 min (34.06 ± 6.18 pmol/l) when compared to the NGT group (22.69 ± 4.04 pmol/l). Homeostasis model assessment of insulin resistance from the NGT and AGM groups had a significant reduction at periods T3 in relation to T1 and T2. Adiponectin levels had increased concentration in both groups before and after surgical weight loss. However, it did not have any statistical difference between periods T1 vs. T2. Conclusions  Weight loss by surgery leads to improvement in the metabolism of carbohydrates in relation to sensitivity to the insulin, contributing to the reduction of type 2 diabetes incidence. This improvement also was expressed by the improvement of the levels of adiponectin and GLP-1.  相似文献   
110.

Background/Aim

Prognosis assessment in surgical patients with hepatocellular carcinoma (HCC) remains controversial. The most widely used HCC prognostic tool is the Barcelona Clinic Liver Cancer (BCLC) classification, but its prognostic ability in surgical patients has not been yet validated. The aim of this study was to investigate the value of known prognostic systems in 400 Italian HCC patients treated with radical surgical therapies.

Methods

We analyzed a prospective database collection (400 surgical, 315 nonsurgical patients) observed at a single institution from 2000 and 2007. By using survival times as the only outcome measure (Kaplan-Meier method and Cox regression), the performance of the BCLC classification was compared with that of Okuda, Cancer of the Liver Italian Program, United Network for Organ sharing TNM, and Japan Integrated Staging Score staging systems.

Results

Two hundred twenty-five patients underwent laparotomy resection; 55, laparoscopic procedures (ablation and/or resection); and 120, liver transplantations. In the surgical group, BCLC proved the best HCC prognostic system. Three-year survival rates of patients in BCLC Stages A, B, and C were 81%, 56%, and 44% respectively, (P < .01); whereas all other tested staging systems did not show significant stratification ability. When all 715 HCC patients were considered, surgery proved to be a significant survival predictor in each BCLC stage (A, B, and C).

Conclusions

BCLC staging showed the best interpretation of the survival distribution in a surgical HCC population. The BCLC treatment algorithm should consider the role of surgery also for intermediate-advanced stages of liver disease.  相似文献   
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