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91.
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93.
The aim of this study was to histologically and biochemically analyze the effects of light-emitting diode therapy (LEDT) associated with resistance training to prevent sarcopenia in ovariectomized rats. Forty female Wistar rats (12 months old, 295–330 g) were bilaterally ovariectomized and divided into four groups (n?=?10 per group): control–sedentary (C), resistance training (T), LEDT–sedentary (L), and LEDT plus resistance training (LT). Trained rats performed a 12-week water-jumping program (3 days per week) carrying a load equivalent to 50–80 % of their body mass strapped to their back. Depending on the group protocol, the LED device (850 nm, 100 mW, 120 J/cm2, spot size 0.5 cm2) was used either as the only method or after the resistance training had been performed. The device was used in the single point contact mode (for 10 min). The irradiated region was the center of the greater trochanter of the right femur and the middle third of the rectus femoris muscle was subsequently analyzed histomorphometrically. Significant increases (p?<?0.05) were noted for the muscle volume of the T (68.1?±?19.7 %), the L (74.1?±?5.1 %), and the LT (68.2?±?11.5 %) groups compared to the C group (60.4?±?5.5 %). There were also significant increases in the concentrations of IGF-1, IL-1, and TNF-α in the muscles of the treated groups (p?<?0.05). Animals in the LT group showed a significant increase in IL-6 compared to T, L, and C groups (p?<?0.05). These findings suggest that resistance training and LEDT can prevent sarcopenia in ovariectomized rats.  相似文献   
94.
Epithelial cells play an important role in reparative events. Therefore, therapies that can stimulate the proliferation and metabolism of these cells could accelerate the healing process. To evaluate the effects of low-level laser therapy (LLLT), human keratinocytes were irradiated with an InGaAsP diode laser prototype (LASERTable; 780?±?3 nm; 40 mW) using 0.5, 1.5, 3, 5, and 7 J/cm2 energy doses. Irradiations were done every 24 h totaling three applications. Evaluation of cell metabolism (MTT assay) showed that LLLT with all energy doses promoted an increase of cell metabolism, being more effective for 0.5, 1.5, and 3 J/cm2. The highest cell counts (Trypan blue assay) were observed with 0.5, 3, and 5 J/cm2. No statistically significant difference for total protein (TP) production was observed and cell morphology analysis by scanning electron microscopy revealed that LLLT did not promote morphological alterations on the keratinocytes. Real-time polymerase chain reaction (qPCR) revealed that LLLT also promoted an increase of type I collagen (Col-I) and vascular endothelial growth factor (VEGF) gene expression, especially for 1.5 J/cm2, but no change on fibroblast growth factor-2 (FGF-2) expression was observed. LLLT at energy doses ranging from 0.5 to 3 J/cm2 promoted the most significant biostimulatory effects on cultured keratinocytes.  相似文献   
95.
Methylglyoxal is a dicarbonyl compound that is physiologically produced by enzymatic and non-enzymatic reactions. It can lead to cytotoxicity, which is mainly related to Advanced Glycation End Products (AGEs) formation. Methylglyoxal and AGEs are involved in the pathogenesis of Neurodegenerative Diseases (ND) and, in these situations, can cause the impairment of energetic metabolism. Astroglial cells play critical roles in brain metabolism and the appropriate functioning of astrocytes is essential for the survival and function of neurons. However, there are only a few studies evaluating the effect of methylglyoxal on astroglial cells. The aim of this study was to evaluate the effect of methylglyoxal exposure, over short (1 and 3?h) and long term (24?h) periods, on glucose, glycine and lactate metabolism in C6 glioma cells, as well as investigate the glyoxalase system and AGEs formation. Glucose uptake and glucose oxidation to CO2 increased in 1?h and the conversion of glucose to lipids increased at 3?h. In addition, glycine oxidation to CO2 and conversion of glycine to lipids increased at 1?h, whereas the incorporation of glycine in proteins decreased at 1 and 3?h. Methylglyoxal decreased glyoxalase I and II activities and increased AGEs content within 24?h. Lactate oxidation and lactate levels were not modified by methylglyoxal exposure. These data provide evidence that methylglyoxal may impair glucose metabolism and can affect glyoxalase activity. In periods of increased methylglyoxal exposure, such alterations could be exacerbated, leading to further increases in intracellular methylglyoxal and AGEs, and therefore triggering and/or worsening ND.  相似文献   
96.
Leukemia is a malignancy of the bone marrow. Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy and accounts for nearly 75% of all newly diagnosed leukemias and 25% of all malignancies in childhood. The aim of the present study was to review the oral health status in children with ALL. Databases were explored using various combinations of the following keywords: "acute lymphoblastic leukemia", "children", "inflammation", "pediatric", "periodontal disease" and "periodontitis". Oral inflammatory conditions including chelitis, gingivitis, herpetic gingivostomatitis, mucositis, oral candidiasis, periodontitis and ulcerations are common manifestations in children with ALL. RESULTS: Periodontal inflammatory conditions and oral mucositis were reported to be significantly higher in children with ALL as compared to healthy controls. Tooth morphological disorders including agenesis, microdontia, short roots and developmental defects in the enamel and dentin were more often observed in children with ALL as compared to healthy controls. Children with ALL have a reduced salivary flow rate, which makes them more susceptible to dental caries as compared to healthy children. Malocclusion due to microdontia may also trigger temporomandibular joint disorders in children with ALL; however, this relationship needs further investigations. CONCLUSION: Oral inflammatory conditions including mucositis and gingivitis are common in children with ALL as compared to healthy children. Tooth morphological disorders including microdontia and enamel and dentin are common manifestations in children with ALL.  相似文献   
97.

Purpose

Questions remain about the polysomnographic findings and the predictors for sleep desaturation in cystic fibrosis (CF) patients. Our study aimed to evaluate sleep parameters in a sample of adult CF patients comparing them with healthy controls and to determine the best predictors of sleep desaturation in CF patients with awake resting peripheral oxygen saturation (SpO2) ??90%.

Methods

In a cross-sectional study, with data collected prospectively, 51 clinically stable adult CF patients (mean age 25.1?±?6.7?years) and 25 age-matched controls underwent an overnight polysomnography and answered sleep questionnaires. CF patients had their pulmonary function, 6-min walk test, and echocardiography assessed.

Results

CF patients and control subjects had similar sleep architecture. However, CF patients had impaired subjective sleep quality and a higher arousal index than controls. The apnea?Chypopnea index was similar in both groups, and only two CF patients (3.9%) fulfilled the criteria for obstructive sleep apnea syndrome. Sleep desaturation was more common in CF patients (29.4% vs 0%; p?2 was the single best variable associated with sleep desaturation in CF population (p?2 <94% had a sensitivity, specificity, positive and negative predictive value for sleep desaturation of, respectively, 93.3%, 100%, 100%, and 97.3%.

Conclusions

CF patients had a worse subjective sleep quality and small changes in sleep architecture. In nonhypoxic, adult CF patients, sleep desaturation is common, is not associated with obstructive sleep events, and can be accurately predicted by awake resting SpO2 <94%.  相似文献   
98.
99.

Introduction

Bacterial contamination from viscerotomy is a barrier to natural orifice translumenal endoscopic surgery (NOTES). The aim of this survival study is to evaluate pure (totally) transvaginal NOTES bacterial contamination compared with laparoscopy in pigs.

Methods

Twelve adult female pigs underwent peritoneoscopy with liver and peritoneal biopsies, using either laparoscopy (Glap, six animals) or pure transvaginal (GNOTES) access, and were maintained alive for 7 days. In all animals, blood cultures were taken at baseline, and after 24 h and 7 days postoperatively. Swab cultures from vagina (GNOTES) and skin (Glap) were obtained pre- and post-antisepsis. Peritoneal fluid culture was obtained at necropsy. For statistical analysis, Glap and GNOTES were compared for presence of positive bacterial cultures (qualitative bacterial analysis) using Fisher’s test, with level of significance set at p < 0.05.

Results

All animals had good postoperative outcome. One animal had transient perioperative bleeding from a transvaginal access. Two animals in Glap and one in GNOTES had positive blood cultures after the procedure. All animals from GNOTES and Glap presented with mixed flora pre-antisepsis. After antisepsis, one animal (GNOTES) presented with a positive vaginal swab culture (a single bacterial strain was identified). There was no positive skin swab culture in Glap. There were no signs of intra-abdominal infection at necropsy. In two animals, one from Glap and another from GNOTES, intra-abdominal culture was positive for Corynebacterium spp. and Escherichia coli, respectively. There was no correlation between the bacterial flora found at the access site and in the peritoneal cultures.

Conclusions

Pure transvaginal peritoneoscopy with liver and peritoneal biopsy in swine is feasible and associated with bacterial contamination comparable to laparoscopy. Peritoneal bacterial contamination was clinically insignificant after 1 week postoperatively. Preoperative antisepsis provided significant reduction of bacterial load prior to transvaginal and laparoscopic procedures.  相似文献   
100.
It is widely accepted that tabagism is a predisposing factor to oral candidosis and cumulate data suggest that cigarette compounds may increase candidal virulence. To verify if enhanced virulence occurs in Candida albicans from chronic smokers, a cohort of 42 non-smokers and other of 58 smokers (all with excellent oral conditions and without signs of candidosis) were swabbed on tong dorsum and jugal mucosa. Results showed that oral candidal loads do not differ between smoker and non-smokers. Activities of secreted aspartyl-protease (Sap), phospholipase, chondroitinase, esterase-lipase, and haemolysin secretions were screened for thirty-two C. albicans isolates. There were detected significant increments in phospholipasic and chondroitinasic activities in isolates from non-smokers. For other virulence factors, no differences between both cohorts were achieved.  相似文献   
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