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71.
ObjectiveThe aim of the study was to evaluate the effect of topical fluoride gel NaF 2% application on antioxidant parameters of whole saliva from children.DesignThe saliva mechanically stimulated with parafilm was collected from 25 children (6–12 years) attending the Clinic of Paediatric Dentistry of Universidade Cruzeiro do Sul, São Paulo, Brazil, before (control group) and immediately after application of neutral fluoride gel NaF 2% (fluoride-gel group), according to the Standards for Research Using Human Subjects, Resolution 196/96 of the USA National Health Council of 10/10/1996. Afterwards, pre-post ferric-reducing antioxidant power (FRAP), trolox-equivalent antioxidant capacity (TEAC), uric acid, reduced/oxidised glutathione content (GSH/GSSG) and total peroxidase activity (TPO) were evaluated in whole saliva of both groups.ResultsAll non-enzymatic antioxidant parameters were augmented by fluoride-gel NaF 2% application, whereas a notable reduction (31%) of peroxidase activity was concomitantly observed in the children's saliva (p  0.05). Nevertheless, the reducing power of saliva was kept unaltered under these circumstances (p  0.05).ConclusionsDespite the reduced activity of peroxidase (an important antimicrobial and antioxidant enzyme), the topical fluoride gel NaF 2% favourably stimulated the release of non-enzymatic antioxidant components of saliva, sustaining the reducing power of saliva and the natural defences of the oral cavity.  相似文献   
72.
Data entry and its verification are important steps in the process of data management in clinical studies. In Japan, a kind of visual comparison called the reading aloud (RA) method is often used as an alternative to or in addition to the double data entry (DDE) method. In a typical RA method, one operator reads previously keyed data aloud while looking at a printed sheet or computer screen, and another operator compares the voice with the corresponding data recorded on case report forms (CRFs) to confirm whether the data are the same. We compared the efficiency of the RA method with that of the DDE method in the data management system of the Japanese Registry of Renal Transplantation. Efficiency was evaluated in terms of error detection rate and expended time. Five hundred sixty CRFs were randomly allocated to two operators for single data entry. Two types of DDE and RA methods were performed. Single data entry errors were detected in 358 of 104,720 fields (per-field error rate=0.34%). Error detection rates were 88.3% for the DDE method performed by a different operator, 69.0% for the DDE method performed by the same operator, 59.5% for the RA method performed by a different operator, and 39.9% for the RA method performed by the same operator. The differences in these rates were significant (p<0.001) between the two verification methods as well as between the types of operator (same or different). The total expended times were 74.8 hours for the DDE method and 57.9 hours for the RA method. These results suggest that in detecting errors of single data entry, the RA method is inferior to the DDE method, while its time cost is lower.  相似文献   
73.
Retinal pigment epithelial (RPE) cells play critical roles in the maintenance of visual function, partly by secreting various biologically active factors that modulate the intraocular environment. Recent studies suggest involvement of Wnt proteins secreted by RPE cells in the pathogenesis of photoreceptor degeneration. In the present study, we examined, via the luciferase assay, the effect of media conditioned by RPE cells (RPE-CM) on activity of the canonical Wnt pathway in vitro. We isolated primary RPE cells from Long-Evans rats at P6-P9. In culture, these cells formed a monolayer with polygonal cell morphology and demonstrated repigmentation at confluency and immunoreactivity for ZO-1, a marker for tight junctions. To evaluate the effect of RPE-CM on the canonical Wnt pathway, we replaced the culture media of COS-7 cells transfected with (Tcf)(7)LUC, a multimeric Tcf-responsive element luciferase reporter construct, with RPE-CM and measured luciferase activity with or without Wnt3a or SB216763, a specific GSK3 inhibitor. RPE-CM did not enhance basal or Wnt3a-induced (Tcf)(7)LUC activity; instead, this activity decreased by 60%. RPE-CM also reduced SB216763-induced (Tcf)(7)LUC activity by 65%, which suggests that the inhibitory effect of RPE-CM is probably due to intracellular crosstalk rather than extracellular antagonism. RPE cells may thus be able to modulate the intraocular environment by regulating the canonical Wnt pathway.  相似文献   
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75.
PurposeMüller glial–mesenchymal transition (GMT) is reported as the fibrogenic mechanism promoted by TGF-β–SNAIL axis in Müller cells transdifferentiated into myofibroblasts. Here we show the multifaceted involvement of TGF-β in diabetic fibrovascular proliferation via Müller GMT and VEGF-A production.MethodsSurgically excised fibrovascular tissues from the eyes of patients with proliferative diabetic retinopathy were processed for immunofluorescence analyses of TGF-β downstream molecules. Human Müller glial cells were used to evaluate changes in gene and protein expression with real-time quantitative PCR and ELISA, respectively. Immunoblot analyses were performed to detect TGF-β signal activation.ResultsMüller glial cells in patient fibrovascular tissues were immunopositive for GMT-related molecular markers, including SNAIL and smooth muscle protein 22, together with colocalization of VEGF-A and TGF-β receptors. In vitro administration of TGF-β1/2 upregulated TGFB1 and TGFB2, both of which were suppressed by inhibitors for nuclear factor-κB, glycogen synthase kinase-3, and p38 mitogen-activated protein kinase. Of the various profibrotic cytokines, TGF-β1/2 application exclusively induced Müller glial VEGFA mRNA expression, which was decreased by pretreatment with small interfering RNA for SMAD2 and inhibitors for p38 mitogen-activated protein kinase and phosphatidylinositol 3-kinase. Supporting these findings, TGF-β1/2 stimulation to Müller cells increased the phosphorylation of these intracellular signaling molecules, all of which were also activated in Müller glial cells in patient fibrovascular tissues.ConclusionsThis study underscored the significance of Müller glial autoinduction of TGF-β as a pathogenic cue to facilitate diabetic fibrovascular proliferation via TGF-β–driven GMT and VEGF-A–driven angiogenesis.  相似文献   
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77.
Reconstructive methods following pancreaticoduodenectomy in our department are discussed and evaluated in this study. Between January 1980 and November 1990 fifty-two consecutive patients underwent pancreaticoduodenectomy because of pancreas head disease. Thirty-one patients underwent pancreaticojejunostomy and twenty-one had pancreaticogastrostomy as reconstructive procedures. Mortality rate was 6% in pancreaticojejunstomy versus zero in pancreaticogastrostomy. Six patients had leakage from the pancreaticojejunostomy, but only one patient had necrosis of the gastric stump and leakage from the pancreaticogastrostomy. This case had previous distal gastrectomy done for gastric ulcer. The residual stomach might not have been large enough, and the blood supply of the gastric stump might not have been adequate for pancreaticogastrostomy. Except for this case, none was observed with leakage from the pancreatic anastomosis in the pancreaticogastrostomy group. No statistical significance in operating time or blood loss was observed between the two methods. The pancreaticogastrostomy cases without complications had significantly less loss of body weight than those with pancreaticojejunostomy at the date of discharge (p < 0.05). It is concluded that pancreaticogastrostomy is the safer reconstructive method following pancreaticoduodenectomy, although it may not be indicated in patients with prior gastrectomy.  相似文献   
78.
The day of the week of admission may influence the length of stay and in-hospital death. However, the association between the admission day of the week and in-hospital outcomes has been inconsistent in heart failure (HF) patients among studies reported from Western countries. We thus analyzed this association in HF patients encountered in routine clinical practice in Japan. We studied the characteristics and in-hospital treatment in 1620 patients hospitalized with worsening HF by using the database of the Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD). Patients were divided into two groups according to weekday (n = 1355; 83.6 %) or weekend admission (n = 265; 16.4 %). The mean age was 70.7 years and 59.4 % were male. Etiology was ischemic in 34.0 %, and mean left ventricular ejection fraction was 42.5 %. Patients admitted on the weekend were significantly older and had more comorbidities, and more severe symptoms and signs of HF on admission. Length of stay was comparable between weekend and weekday admission (35.2 ± 47.0 days vs 33.6 ± 32.0 days, P = 0.591). Crude in-hospital mortality did not differ between patients admitted on the weekend and weekdays (7.5 % vs 5.2 %, P = 0.136). Even after adjustment for covariates in multivariable modeling with patients admitted on weekday as the reference, in-hospital death was comparable between patients admitted on the weekend and weekdays (adjusted odds ratio 1.125, 95 % confidence interval 0.631–2.004, P = 0.691). Among patients hospitalized for worsening HF, admission day of the week did not affect in-hospital death and length of stay.  相似文献   
79.
Long-term surviving recipients of allogeneic hematopoietic stem cell transplantation (HSCT) often suffer from diabetes mellitus (DM). We sought to identify risk factors for the development of post-transplant DM and impaired glucose tolerance (IGT) in pediatric HSCT patients. Glucose tolerance statuses were evaluated in 22 patients aged 6.3–21.8 years who had received allogeneic HSCT between the ages of 0.8–13.5 years. Five patients were diagnosed as having type 2 DM, and treated with insulin or oral hypoglycemic agents. Five patients were included in the IGT group, and the remaining 12 children were in the normal glucose tolerance (NGT) group. The cumulative incidence of DM plus IGT was 11.6 % at 5 years and 69.3 % at 10 years. None of the patients were obese/overweight and none had a family history of DM. There were no significant differences in serum levels of leptin and adiponectin between the DM + IGT and the NGT groups. An average preprandial glucose levels in the DM + IGT group were significantly higher than those in the NGT group from preparative conditioning to 60 days after HSCT. In multivariate analysis, an age of ≥6 years at the time of HSCT was significantly associated with the development of DM + IGT. Additionally, careful follow-up is necessary, even for NGT patients.  相似文献   
80.
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