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81.
Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P = 0.025 OR 2.25 CI 1.10–4.59 and P = 0.032 OR 2.32 CI 1.07–5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV.  相似文献   
82.

Purpose

Regulatory T cells are involved in the clinical course of chronic Chagas disease, possibly because they exercise a control in the patient’s inflammatory response to Trypanosoma cruzi. This study analyzed the levels of CD4?+?CD25+ T cells in chronic Chagas disease patients after in vitro stimulation of the peripheral blood mononuclear cells with CRA (Cytoplasmic Repetitive Antigen) or FRA (Flagellar Repetitive Antigen) T. cruzi antigens.

Methods

Groups of patients with the cardiac form and indeterminate form; and non-infected individuals, were selected. The CD4?+?CD25+ T lymphocyte population, as well as the FoxP3 expression and the IL10 production, were evaluated by flow cytometry after stimulation with CRA or FRA.

Result

The IND group presented higher levels of CD4?+?CD25+ T cells than the CARD group. However, there was no evidence of a relationship between FoxP3 and IL10 with any of the chronic forms.

Conclusions

Our results suggest the possible involvement of CD4?+?CD25+ T cells specific to CRA and FRA in controlling the progression of clinical outcomes. Though, further studies are needed to define which mechanisms activate regulatory T cells and lead to pathology control in chronic human Chagas disease.  相似文献   
83.

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   
84.

Objective

Considering the high incidence of Temporomandibular Disorders (TMD) in the population aged 15-30 years and the fact that students are exposed to stressful psychosocial factors, the purposes of this study were: to verify clinical symptoms and jaw functionality in college students with TMD according to the anxiety/depression (A/D) level and to evaluate the correlation between A/D and functionality, maximum mouth opening (MMO) and pain and muscle activity.

Material and Methods

Nineteen students with TMD diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders underwent two assessments during an academic semester. The evaluations were based on questionnaires (MFIQ - Mandibular Function Impairment Questionnaire; HADS - Hospital Anxiety and Depression Scale), clinical measurements (MMO without pain, MMO and assisted MMO; palpation of joint and masticatory muscles), and electromyography. The HADS scores obtained in the two assessments were used to classify all data as either "high" or "low" A/D. Data normality, differences and correlations were tested with the Shapiro-Wilk test, Student''s t-test (or the Wilcoxon test), and Spearman test, respectively. The alpha level was set at 0.05.

Results

None of the clinical variables were significantly different when comparing low and high A/D data. In low A/D there was a significant correlation between HADS score and: MFIQ (P=0.005, r=0.61), and MMO without pain (P=0.01, r=-0.55).

Conclusions

Variation in A/D level did not change clinical symptoms or jaw functionality in college students with TMD. Apparently, there is a correlation between TMJ functionality and A/D level, which should be further investigated, taking into account the source of the TMD and including subjects with greater functional limitation.  相似文献   
85.
The potential use of amino acids by ruminal microorganisms converting them into microbial protein for ruminants makes it challenging to supplement these nutrients in an accessible form in animals’ diets. Several strategies to protect amino acids from ruminal degradation were reported, producing amino acids available for the protein used in the intestine called “bypass.” The intercalation of biomolecules in clay mineral minerals has gained notoriety due to its ability to support, protect, transport, physicochemical properties and non-toxicity. This study aimed to investigate the incorporation of L-lysine (Lys), L-methionine (Met), and L-tryptophan (Trp) amino acids in the clay minerals sepiolite (Sep) and Veegum® (Veg) using the adsorption method. The characterization techniques of X-ray diffraction and infrared spectroscopy indicated the presence of biomolecules in the inorganic matrices. Elemental and thermal analyzes monitored the percentages of incorporated amino acids. They showed better incorporation capacities for Veg, such as Met-Veg < Lys-Veg < Trp-Veg and Lys-Sep < Met-Sep < Trp-Sep for sepiolite, except for the incorporation of Met. Matrices provide a promising alternative for planning the administration of biomolecules, using essential amino acids as models, and may offer an alternative to improve functional diet strategies.  相似文献   
86.
The association between dietary patterns and cardiometabolic risk factors is not well understood among adults in India, particularly among those at high risk for diabetes. For this study, we analyzed the data of 1007 participants (age 30–60 years) from baseline and year one and two follow-ups from the Kerala Diabetes Prevention Program using multi-level mixed effects modelling. Dietary intake was measured using a quantitative food frequency questionnaire, and dietary patterns were identified using principal component analysis. Two dietary patterns were identified: a “snack-fruit” pattern (highly loaded with fats and oils, snacks, and fruits) and a “rice-meat-refined wheat” pattern (highly loaded with meat, rice, and refined wheat). The “snack-fruit” pattern was associated with increased triglycerides (mg/dL) (β = 6.76, 95% CI 2.63–10.89), while the “rice-meat-refined wheat” pattern was associated with elevated Hb1Ac (percentage) (β = 0.04, 95% CI 0.01, 0.07) and central obesity (OR 1.16, 95% CI 1.01, 1.34). These findings may help inform designing dietary interventions for the prevention of diabetes and improving cardiometabolic risk factors in high-diabetes-risk individuals in the Indian setting.  相似文献   
87.
Outbreaks of the Zika, dengue, and chikungunya viruses, especially in the Americas, pose a global threat due to their rapid spread and difficulty controlling the vector. Extreme phenotypes are often observed, from asymptomatic to severe clinical manifestations, which are well-studied in dengue. Host variations are also important contributors to disease outcomes, and many case-control studies have associated single nucleotide polymorphisms (SNPs) with severe dengue. Here, we found that the TC genotype and T-carriers for SNP rs1285933 in the C-type lectin superfamily member 5 (CLEC5A) gene was associated with severe dengue in a Northern Brazilian population (OR = 2.75 and p-value = 0.01, OR = 2.11 and p-value = 0.04, respectively). We also tested the functional effect of the CLEC5A protein and found that it is upregulated on the surface of human monocytes after in vitro dengue infection. CLEC5A was correlated with viral load inside the monocytes (Spearman r = 0.55, p = 0.008) and TNF production in culture supernatants (Spearman r = 0.72, p = 0.03). Analysis of mRNA in blood samples from DENV4-infected patients exhibiting mild symptoms showed that CLEC5A mRNA expression is correlated with TNF (r = 0.67, p = 0.0001) and other immune mediators. Monocytes from rs1285933 TT/TC individuals showed lower CLEC5A expression compared to CC genotypes. However, in these cells, CLEC5A was not correlated with TNF production. In summary, we confirmed that CLEC5A is genetically associated with dengue severity outcome, playing a central role during the immune response triggered by a dengue viral infection, and rs1285933 is a relevant SNP that is able to regulate signaling pathways after interactions between the dengue virus and CLEC5A receptors.  相似文献   
88.
PURPOSE: To evaluate the intra-operative performance and clinical outcome of a new commercially available stent-graft for the treatment of thoracic aortic diseases. METHODS AND PATIENTS: From January 2003 to October 2004, 45 consecutive patients received endovascular treatment with the Zenith TX1 device for diseases of the thoracic aorta at a single center in northern Italy. Indications included disease of the descending thoracic aorta in 26 cases, of the aortic arch in 17 cases and of the thoraco-abdominal aorta in two cases. We treated 38 atherosclerotic aneurysms, two post-traumatic aortic ruptures, two penetrating ulcers, two chronic dissections and one case was treated for aortic bleeding after voluntary acid ingestion for attempted suicide. General anesthesia was used in 20 cases. Combined or hybrid endovascular and open surgical repair was performed in 11 patients. Mean follow-up was 7 months (range 1-22 months). RESULTS: Technical success was obtained in 44 patients (98%). One primary type I endoleak occurred (2%). ICU was used in 12 cases with a mean stay of 1 day. The mean hospital stay was 6 days (range 4-13 days). There were no hospital deaths or strokes but one transient paraplegia (2%). A type II endoleak was observed in one case and resolved spontaneously 1 month later. No aneurysm enlargement, endograft migration or structural failures were observed during follow-up. Two late unrelated-deaths were observed. CONCLUSIONS: This stent-graft does not fulfill all the characteristics of the ideal graft, however, it proved to be safe and allowed satisfactory short term results in this group of patients treated at a single center.  相似文献   
89.
Studies involving the transformation of lignocellulosic biomass into high value-added chemical products have been intensively conducted in recent years. Its matrix is mainly composed of cellulose, hemicellulose and lignin, being, therefore, an abundant and renewable source for obtaining several platform molecules, with levoglucosan (LG) standing out. This anhydrous carbohydrate can be acylated to obtain carbohydrate fatty acid esters (CFAEs). Here, these compounds were obtained via enzymatic acylation of LG, commercially obtained (Start BioScience®), with different acyl donors in continuous flow. Through the experimental design using a model reaction, it was possible to optimize the reaction conditions, temperature and residence time, obtaining a maximum conversion at 61 °C and 77 min. In addition, there was a productivity gain of up to 100 times in all comparisons made with the batch system. Finally, CFAEs were applied in tests of interfacial tension and biological activity. For a mixture of 4- and 2-O-lauryl-1,6-anhydroglucopyranose (MONLAU), the minimum interfacial tension (IFTmin) obtained was 96 mN m−1 and the critical micelle concentration (CMC) was 50 mM. Similar values were obtained for a mixture of 4- and 2-O-palmitoyl-1,6-anhydroglucopyranose (MONPAL), not yet reported in the literature, of 88 mN m−1 in 50 mM. For a mixture of 4- and 2-O-estearyl-1,6-anhydroglucopyranose (MONEST) and 4- and 2-O-oleoyl-1,6-anhydroglucopyranose (MONOLE), CMC was higher than 60 mM and IFTmin of 141 mN m−1 and 102 mN m−1, respectively. Promising data were obtained for minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of MONLAU against Staphylococcus aureus strains at 0.25 mM.

Ipase-catalyzed transesterification of LG under continuous flow conditions.  相似文献   
90.
This study aimed to assess factors associated with overweight and obesity in adults from Rio Branco, Acre, in the western Brazilian Amazon. This is a cross-sectional, population-based study conducted in Rio Branco, which used data on individuals aged 18 years or older collected by the 2019 National Health Survey. Software R version 4.0.5 was used to estimate the prevalence of overweight and obesity, prevalence ratios, and 95% confidence intervals. Multiple analysis was performed by Poisson’s regression with robust variance and hierarchical selection of variables. This study included 1217 adults. The prevalence of overweight was 58.2% (95%CI: 54.7–61.6) and of obesity, 20.1% (95%CI: 17.2–23.4). The factors associated with overweight were arterial hypertension (AdjPR: 1.45; 95%CI: 1.31–1.61), physical inactivity (AdjPR: 1.19; 95%CI: 1.04–1.36), age group (25–39 years, AdjPR: 1.49; 95%CI: 1.10–2.00; 40–59 years, AdjPR: 1.69; 95%CI: 1.28–2.23; 60 years or older, AdjPR: 1.37; 95%CI: 1.01–1.87); and smoking (AdjPR: 0.62; 95%CI: 0.41–0.93). The factors associated with obesity were arterial hypertension (AdjPR: 1.80; 95%CI: 1.41–2.30) and diabetes mellitus (AdjPR: 1.52; 95%CI: 1.08–2.13). Smoking and female sex remained in the hierarchical model for obesity, even without statistical significance. Despite intervention guidelines for these chronic diseases, there is a need for the public recognition of overweight and obesity and their possible associated factors in the Amazon and other regions with similar socioeconomic and demographic characteristics.  相似文献   
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