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91.
Karla V. G. Lima Raquel P. A. Lima Maria C. R. Gonçalves Joel Faintuch Liana C. S. L. Morais Luiza S. R. Asciutti Maria J. C. Costa 《Obesity surgery》2014,24(5):771-776
Background
To our knowledge, the frequency of serum chromium deficiency in patients awaiting bariatric surgery has not been determined. This study was designed to assess chromium concentration and its association with glycemic levels and lipid profile in patients prior to bariatric surgery.Methods
This study recruited 73 candidates for bariatric surgery between March and September 2012. Their sociodemographic, anthropometric, and biochemical data were collected.Results
Of the 73 patients, 55 (75.3 %) were women (75.34 %). Mean patient age was 37.20?±?9.92 years, and mean body mass index was 47.48 kg/m2 (range, 43.59 to 52.50 kg/m2). Chromium deficiency was observed in 64 patients (87.7 %). Correlation analysis showed significant negative relationships between chromium concentration and BMI and zinc concentration and a significant positive relationship between chromium and glycated hemoglobin. Multiple linear regression analysis showed that serum chromium concentration was significantly associated with total cholesterol (β?=?0.171, p?=?0.048) and triglyceride (β?=??0.181, p?=?0.039) concentrations.Conclusions
Serum chromium deficiency is frequent in candidates for bariatric surgery and is associated with total cholesterol and triglyceride concentrations. Early nutritional interventions are needed to reduce nutritional deficiencies and improve the lipid profile of these patients. 相似文献92.
Clevson P. da Costa Jessyca K. F. Rodrigues Viviane M. S. de Morais Carlos A. d. N. de Andrade Patrícia A. F. Neves Kledoaldo Lima 《Journal of medical virology》2020,92(12):3219-3229
Information on human immunodeficiency virus (HIV) molecular epidemiology is required to verify HIV/AIDS (acquired immune deficiency syndrome) epidemic dynamics in different regions, as well as provide support for response to antiretroviral therapy, transmission of resistance mutations, disease progression, and viral spread. The aim of this study was to conduct a systematic review and meta-analysis of the frequency of HIV-1 subtypes in Northeast Brazil. Seventy-six articles that refer to HIV-1 and its subtypes in the Northeast Brazil and published between 1 January 1999 and 31 August 2019 were identified. We included 27 articles for the qualitative synthesis, thus analyzing results from 4466 patients and 4298 genomic sequences. The results showed that subtypes B, F, and C and recombinant BF were responsible for 76% (IC95%: 71-80), 8% (IC95%: 5-11), 2% (IC95%: 2-3), and 7% (IC95%: 4-12) infections, respectively. The highest proportion of subtype B infections (82.2%) was observed in Piauí, while the subtype F had a high frequency in Pernambuco (23.4%). Bahia presented 11.6% of the proportion of recombinant BF. In addition, several recombinants such as AG, BC, BCF, and BD have been identified in the region. This is the first systematic review and meta-analysis on the HIV-1 subtype distribution in Northeast Brazil and has shown a high circulating viral diversity. Although subtype B is predominant in Brazil, a large frequency of non-B subtypes has also been found, which may have consequences for response to antiretroviral therapy, disease progression, and transmission. Thus, HIV molecular epidemiological data are essential for epidemic prevention and control strategies. 相似文献
93.
Nathalie Pattyn Olivier Mairesse Aisha Cortoos José Morais Eric Soetens Bart Roelands Annick van den Nest Régine Kolinsky 《International journal of psychophysiology》2014
In the present experiment, cognitive control under stress was investigated using a real-life paradigm, namely an evaluation flight for military student pilots. The magnitude of cognitive interference on color–word, numerical and emotional Stroop paradigms was studied during a baseline recording and right before the test flight. Cardio-respiratory parameters were simultaneously assessed during rest and the performance of the Stroop tasks. Cognitive data suggested a different speed/accuracy trade-off under stress, and no modulation of the interference effect for color words or numerical stimuli. However, we observed a major increase in error rates for specific emotional stimuli related to the evaluation situation in the stress condition. The increase in cognitive interference from emotional stimuli, expressed as an increase in error rates, was correlated to the decreased cardiac reactivity to challenge in the stress situation. This relationship is discussed in the framework of Sanders' (1983) model of stress and performance. In terms of future research, this link warrants a fruitful lead to be followed for investigating the causal mechanism of performance decrements under the influence of stress. 相似文献
94.
Karina Morais Faria Thais Bianca Brandão Ana Carolina Prado Ribeiro Adriele Ferreira Gouvêa Vasconcellos Icaro Thiago de Carvalho Fernando Freire de Arruda Gilberto Castro Junior Vanessa Cristina Gross Oslei Paes Almeida Marcio Ajudarte Lopes Alan Roger Santos-Silva 《Journal of endodontics》2014
Introduction
Teeth are often included in the radiation field during head and neck radiotherapy, and recent clinical evidence suggests that dental pulp is negatively affected by the direct effects of radiation, leading to impaired sensitivity of the dental pulp. Therefore, this study aimed to investigate the direct effects of radiation on the microvasculature, innervation, and extracellular matrix of the dental pulp of patients who have undergone head and neck radiotherapy.Methods
Twenty-three samples of dental pulp from patients who finished head and neck radiotherapy were analyzed. Samples were histologically processed and stained with hematoxylin-eosin for morphologic evaluation of the microvasculature, innervation, and extracellular matrix. Subsequently, immunohistochemical analysis of proteins related to vascularization (CD34 and smooth muscle actin), innervation (S-100, NCAM/CD56, and neurofilament), and extracellular matrix (vimentin) of the dental pulp was performed.Results
The morphologic study identified preservation of the microvasculature, nerve bundles, and components of the extracellular matrix in all studied samples. The immunohistochemical analysis confirmed the morphologic findings and showed a normal pattern of expression for the studied proteins in all samples.Conclusions
Direct effects of radiotherapy are not able to generate morphologic changes in the microvasculature, innervation, and extracellular matrix components of the dental pulp in head and neck cancer patients. 相似文献95.
Mary A. S. Melo Weslanny A. Morais Vanara F. Passos Juliana P. M. Lima Lidiany K. A. Rodrigues 《Clinical oral investigations》2014,18(4):1343-1350
Introduction
Fluoride-containing materials have been suggested to control enamel demineralization around orthodontic brackets during the treatment with fixed appliances. The improvement of their properties has been made through innovations, such as the application of nanotechnology by incorporation of nanofillers.Objective
This in vitro study evaluated the capacity of fluoride releasing and enamel demineralization inhibition of fluoride-releasing nanofilled cement around orthodontic brackets using an artificial caries biofilm model.Materials and methods
Forty bovine enamel discs were selected by evaluating surface microhardness and randomized into four groups (n?=?10): non-fluoride-releasing microfilled composite, fluoride-releasing microfilled composite, resin-modified glass ionomer cement (RMGI), and fluoride-releasing nanofilled composite (FN). After brackets bonding in each disc, the specimens were subjected to a cariogenic challenge through a Streptococcus mutans biofilm model. After the experimental period, the biofilm formed around the brackets was collected for fluoride analysis and the mineral loss around the brackets was determined by integrated demineralization via cross-sectional microhardness measurement at 20 and 70 μm from the bracket margin. Additionally, samples of each group were subjected to energy-dispersive X-ray spectroscopy (EDX) analysis examined under a scanning electron microscopy (SEM). ANOVA followed by Tukey test were applied for fluoride concentration and mineral loss data, respectively.Results
At both distances, only RMGI statistically differed from the other groups presenting the lowest demineralization, although there was a trend to a lower demineralization of enamel around brackets in FN group. Similar condition was found to fluoride concentration and EDX/SEM analysis.Conclusions
Under the cariogenic exposure condition of this study, the fluoride-releasing nanofilled material had similar performance to fluoride-releasing microfilled materials.Clinical relevance
The presence of nanofillers in the fluoride-releasing materials studied did not promote further benefits against caries lesion development around brackets and presented inferior demineralization inhibition than the resin-modified glass ionomer material. 相似文献96.
Aldo Miro de Medeiros Karoline de Sousa Castro Mayara Lopes Gundim de Macêdo Aruzza Mabel de Morais Araújo Djalma Ribeiro da Silva Amanda Duarte Gondim 《RSC advances》2022,12(16):10163
Catalytic pyrolysis of vegetable oil is one of the potential routes to convert oil to drop-in biofuels, known as renewable hydrocarbons. In this paper, we explored catalytic pyrolysis of coconut oil using SBA-15 impregnated with Ni in proportions of 1% to 5% to produce sustainable aviation fuel. The catalysts were synthesized, calcined and then characterized by XRD, FTIR, SEM, and EDS. In order to better understand the behavior of this process, thermal and kinetic studies were carried out by thermogravimetry. The TG curves of vegetable oil with (10%) and without catalysts were obtained at heating rates of 5, 15 and 20 °C min−1, in the temperature range between 30 and 600 °C. The kinetic parameters were calculated by the Ozawa–Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS) methods. In the kinetic study, lower heat rates promoted higher conversions and the KAS model suits the process. The results calculated for the OC sample using the two kinetic models showed an increase in the Ea energy as the conversion progressed to a certain point. Catalytic pyrolysis experiments were performed in a one-stage tubular reactor at 500 °C with a catalyst loading of 10 wt% on the basis of mass of oil. The catalyst with 5% Ni showed greater presence of hydrocarbons and greater formation of water, indicating that the deoxygenation process occurred through decarbonylation. With this, the present study was successful in the development of methodologies for obtaining hydrocarbons with a composition close to that of drop-in fuels, compared to the process carried out with vegetable oil in the absence of catalysts.Catalytic pyrolysis of vegetable oil is one of the potential routes to convert oil to drop-in biofuels, known as renewable hydrocarbons. 相似文献
97.
98.
99.
The form of the anterior mandible in 45 patients was assessed before, immediately after, and 1 year after genioplasty. A specific, consistent pattern of bone apposition and resorption was observed after advancement genioplasty. A consistent but inverse apposition-resorption pattern was observed after reduction genioplasty. In view of the observed pattern of bony change, it is recommended that fixation devices for genioplasty be placed in areas of future bone deposition. 相似文献
100.
Rodrigo Marcel Valentim da Silva Jania Cacilda Santos Waleska Lourena Marinho de Carvalho Liliane Santos de Vasconcellos Aline Brito Ferreira de Castro Fbio dos Santos Borges Eneida de Morais Carreiro Patrícia Froes Meyer 《The Journal of clinical and aesthetic dermatology》2022,15(1):E66
Background The mechanism of fat reduction from radiofrequency occurs via the thermal stimulation of adipocyte metabolism, causing a lipase-mediated triglyceride enzyme degradation, apoptosis, and adipocyte rupture. Ultracavitation promotes fat reduction using adipose cell destruction through mechanical stimulus. The literature on the combination of these two physical agents, named ultrafrequency, is still scarce and requires consistent analysis of the effects of this therapy combination.ObjectiveThe objective of this study was to investigate the effects of radiofrequency associated with ultracavitation in the treatment of abdominal subcutaneous tissue of women.MethodsThis was a prospective, randomized clinical trial in which 45 participants were divided into three distinct groups: the control group (no treatment); ultracavitation group; and ultracavitation and radiofrequency (UCV+RF) group, each with 15 volunteers. The following variables were evaluated: weight, perimetry, plicometry, ultrasonography, treatment reactions, and patient satisfaction.ResultsThe participants in the UCV+RF group presented a more significant decrease in adipose tissue, which was verified through all the evaluation methods.ConclusionBased on our results, the simultaneous application of ultracavitation and radiofrequency generated a reduction in localized adiposity superior to the isolated use of ultracavitation. 相似文献