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31.
Longitudinal studies evaluating the relationship between UPF consumption and the incidence of Metabolic Syndrome (MetS) and its components are still scarce. This study aimed to evaluate the effect of UPF consumption on the incidence of MetS and its components in adults. A prospective study was conducted with 896 participants from the 1978/79 Ribeirão Preto cohort, São Paulo, Brazil. UPF consumption was evaluated in %kcal and %g at ages 23–25 years. Incidence of MetS and its components were estimated at ages 37–39 years, according to the Joint Interim Statement criteria. Poisson regression was used to assess associations, and interactions with sex were investigated. UPF consumption had no association with MetS (%kcal Adjusted PR: 1.00; 95% CI: 0.99–1.01; %g Adjusted PR: 1.00; 95% CI: 0.99–1.01). However, women with higher UPF consumption, in %kcal and %g, had a higher risk of abdominal obesity (%kcal: p = 0.030; %g: p = 0.003); and women with higher UPF consumption, in %g, had a higher risk of low HDL-cholesterol (p = 0.041). For the other components of MetS, no significant associations were observed in either sex. These findings suggest evidence of no association between UPF consumption and MetS; however, consumption of UPF was associated with increased WC and low HDL-c, but only in women.  相似文献   
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Rational synthesis and simple methodology for the purification of large (35–45 nm in lateral size) and flat (1.0–1.5 nm of height) nitrogen-doped graphene oxide quantum dots (GOQDs) are presented. The methodology allows robust metal-free and acid-free preparation of N-GOQDs with a yield of about 100% and includes hydrothermal treatment of graphene oxide with hydrogen peroxide and ammonia. It was demonstrated that macroscopic impurities can be separated from N-GOQD suspension by their coagulation with 0.9% NaCl solution. Redispersible in water and saline solutions, particles of N-GOQDs were characterized using tip-enhanced Raman spectroscopy (TERS), photoluminescent, XPS, and UV-VIS spectroscopies. The size and morphology of N-GOQDs were studied by dynamic light scattering, AFM, SEM, and TEM. The procedure proposed allows nitrogen-doped GOQDs to be obtained, having 60–51% of carbon, 34–45% of oxygen, and up to 7.2% of nitrogen. The N-GOQD particles obtained in two hours of synthesis contain only pyrrolic defects of the graphene core. The fraction of pyridine moieties grows with the time of synthesis, while the fraction of quaternary nitrogen declines. Application of TERS allows demonstration that the N-GOQDs consist of a graphene core with an average crystallite size of 9 nm and an average distance between nearest defects smaller than 3 nm. The cytotoxicity tests reveal high viability of the monkey epithelial kidney cells Vero in the presence of N-GOQDs in a concentration below 60 mg L−1. The N-GOQDs demonstrate green luminescence with an emission maximum at 505 nm and sedimentation stability in the cell culture medium.

This paper reveals the methodology for robust preparation of purified nitrogen-doped graphene oxide quantum dots with non-cytotoxic activity against monkey epithelial kidney cells (Vero ATCC® CCL-81™).  相似文献   
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BackgroundUsual treatment regimens with vancomycin often fail to provide adequate serum levels in patients with severe infections.MethodsRetrospective analysis of vancomycin trough serum measurements. The following parameters were calculated by Bayesian analysis: vancomycin clearance, distribution volume, and peak estimated concentrations. The area under the concentration curve (AUC) (total daily dose/24 h clearance of vancomycin) was used to determine the effectiveness of treatment through the ratio of AUC/minimum inhibitory concentration (MIC) above 400, using MIC = 1 μg/mL, based on isolates of Staphylococci in cultures.ResultsSixty-one vancomycin trough measurements were analyzed in 31 patients. AUC/MIC > 400 was obtained in 34 out of 61 dosages (55.7%), but the mean vancomycin dose required to achieve these levels was 81 mg/kg/day. In cases where the usual doses were administered (40–60 mg/kg/day), AUC/MIC > 400 was obtained in nine out of 18 dosages (50%), in 13 patients. Trough serum concentrations above 15 mg/L presented a positive predictive value of 100% and a negative predictive value of 71% for AUC/MIC > 400.ConclusionHigher than usual vancomycin doses may be required to treat staphylococcal infections in children with oncologic/hematologic diseases. Since the best known predictor of efficacy is the AUC/MIC ratio, serum trough concentrations must be analyzed in conjunction with MICs of prevalent Staphylococci and pharmacokinetic tools such as Bayesian analysis.  相似文献   
36.
The present study evaluated the effects of a low-protein diet (LP, 6% protein) on cardiovascular reflexes of Male Fisher rats. Three experimental groups, and their respective controls (15% protein), were used. (1) Baroreceptor reflex (BAR); (2) Bezold-Jarisch reflex (BJR); and (3) Prazosin treated. Dietary restriction began after weaning (three weeks) and lasted for a period of five weeks, after which animals were subjected to the experimental protocols. The BAR group was evaluated through injections of phenylephrine (0.55.0 μg/Kg, i.v.) and sodium nitroprusside (0.77.0 μg/Kg, i.v.) while the BJR was evaluated through injections of serotonin (2.510μg/Kg, i.v.). Our results showed an increased baroreflex gain bradycardia for the LP group (-0.96 ± 0.34 vs. -2.12 ± 1.06 bpm/mmHg) and a larger bradycardia for the BJR the LP group (160 ± 18% greater than controls). Basal cardiovascular parameters were not different between LP and control rats, however LP animals treated with prazosin resulted in a larger fall of blood pressure (-19±3 vs. -28±5 mmHg). In conclusion, LP rats present an increased responsiveness of BAR and BJR, which could contribute to their normal levels of cardiovascular parameters, in spite of the possible increase in the sympathetic vasomotor tonus observed with the prazosin protocol.  相似文献   
37.
The objective of this study was to optimize an internal control to improve SYBR-Green-based qPCR to amplify/detect the BoHV-5 US9 gene in bovine embryos produced in vitro and experimentally exposed to the virus. We designed an SYBR-Green-based binding assay that is quick to perform, reliable, easily optimized and compares well with the published assay. Herein we demonstrated its general applicability to detect BoHV-5 US9 gene in bovine embryos produced in vitro experimentally exposed to BoHV-5. In order to validate the assay, three different reference genes were tested; and the histone 2a gene was shown to be the most adequate for normalizing the qPCR reaction, by considering melting and standard curves (p < 0.05). On the other hand, no differences were found in the development of bovine embryos in vitro whether they were exposed to BoHV-5 reference and field strains comparing to unexposed embryos. The developed qPCR assay may have important field applications as it provides an accurate BoHV-5 US9 gene detection using a proven reference gene and is considerably less expensive than the TaqMan qPCR currently employed in sanitary programs.  相似文献   
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BACKGROUND: Inflammation and oxidative stress have been incriminated in the pathogenesis of IgA nephropathy (IgAN). The aim of the present study was to assess whether markers reflecting these pathophysiologic processes, namely C-reactive protein (CRP) and advanced oxidation protein products (AOPP), would allow-in conjunction with clinical and histopathologic parameters-to predict disease progression. METHODS: Between 1994 and 1997, 120 adult patients with biopsy-proven IgAN were included in a prospective cohort study, and followed until the end of 2002 or start of dialysis. In every patient, we determined plasma levels of CRP and AOPP. These parameters were included, together with clinical data, in a multivariate Cox proportional hazard regression analysis, with halving of baseline creatinine clearance as the primary renal end point. RESULTS: A total of 51 patients reached the renal end point, including 30 who had to start dialysis. With multivariate analysis, the most potent independent risk factors of poor renal outcome were proteinuria > or =1 g/day [proportional hazard risk (HR) = 23.7, P= 0.0001], hypertension (HR = 8.13, P= 0.008), and AOPP plasma level (HR = 1.09 per 10 micromol/L, P= 0.042), whereas angiotensin II inhibitors were protective (HR = 0.19, P= 0.001). CONCLUSION: Our data support the role of oxidative stress in the pathogenesis of IgAN and suggest that patients with proteinuria > or =1 g/day should be eligible for early implemented antioxidant and/or anti-inflammatory therapeutic strategies, with AOPP plasma level as a surrogate marker to evaluate their effects.  相似文献   
40.
An analysis of 300 cases of reduction mammaplasty done utilizing a periareolar approach at the University Hospital of the State of Rio de Janeiro and our own private clinic during the period from September 1989 through October 1995 is presented in this article. The technical evolution of this procedure is described in detail as well as how the complications were eliminated and the aesthetic results improved. A thorough analysis of recommendations and comments on the results are made by the authors.  相似文献   
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