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Objective:

The objective of this study was to demonstrate the sensitivity and specificity of multislice computed tomography (CT) for diagnosis of orbital fractures following different protocols, using an independent workstation.

Materials and methods:

CT images of 36 patients with maxillofacial fractures (symptomatic to orbit region) who were submitted to multislice CT scanning were analyzed, retrospectively. The images were interpreted based on 5 protocols, using an independent workstation: 1) axial (original images); 2) multiplanar reconstruction (MPR); 3) 3D images; 4) association of axial/MPR/3D images and 5) coronal images. The evaluated anatomical sites were divided according to the orbital walls: lateral (with or without zygomatic frontal process fracture); medial; superior (roof) and inferior (anterior, medial). The collected data were analyzed statistically using a validity test (Youden''s J index; p<0.05). The clinical and/or surgical findings (medical records) were considered as the gold standard to corroborate the diagnosis of the anatomical localization of the orbital fracture.

Results:

3D-CT scanning presented sensitivity of 78.9%, which was not superior to that of MPR (84.0%), axial/MPR/3D (90.5%) and coronal images (86.1%). On the other hand, the diagnostic value of axial images was considered limited for orbital fractures region, with sensitivity of 44.2%.

Conclusions:

Except for the axial images, which presented a low sensitivity, all methods evaluated in this study showed high specificity and sensitivity for the diagnosis of orbital fractures according to the proposed methodology. This protocol can add valuable information to the diagnosis of fractures using the association of axial/MPR/3D with multislice CT.  相似文献   
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This study aimed to characterise canine flow cytometry semen analysis, as well as seminal reactive oxygen species dosage using the Golden Retriever breed as model of study. Moreover, we searched for the influence of muscular dystrophy in Golden Retriever dogs on semen parameters. Thirty‐seven semen samples were obtained from healthy Golden Retrievers (n = 15) and from muscular dystrophy affected dogs (n = 22). Sperm‐rich fractions were analysed by standardised breeding soundness examination in addition to the assay of fluorescence assisted cell sorting for acrosome integrity, mitochondrial activity and DNA fragmentation. Volume of ejaculate, per cent of motile spermatozoa and vigour were similar between groups; there were no differences in the per cent of minor and major defects. Integrity of acrosomal membrane, mitochondrial potential and sperm DNA fragmentation had no significant differences between groups either. Animals from control group had higher concentration of spontaneous seminal oxidative species in comparison with affected animals. Dogs affected by dystrophy had seminal parameters similar to those observed in healthy dogs except for the lower concentration of oxidative species. Future studies aiming to establish reference values for canine seminal parameters should be considered preferably with distinction of breeds.  相似文献   
35.
Type I diabetes mellitus (T1DM) is an autoimmune disorder featured by raised glucoses levels. It has been hypothesised that raised glucose levels in T1DM might be recognised as PAMPs, leading to immune response by overloading the cell receptors for pathogens recognition. DC-SIGN is a transmembrane protein, present in dendritic cells (DC) and macrophages: it has an important role in inflammatory response and T cells activation. Notably, DC-SIGN activation and triggering of the immune response depend on the type of ligand, which may lead to a pro or anti-inflammatory pathway. In our association study, we analysed the SNPs rs4804803 (−336 A>G) and rs735239 (−871 A>G), both at DC-SIGN promoter region, in 210 T1DM patients and 157 healthy controls, also looking for a correlation with the age of onset of the disease. We found that the allele G and genotypes G/G and A/G of SNP-871 (rs735239), as well as the alleles G-G (rs735239-rs4804803) and genotypes combined AA-GG (rs735239-rs4804803) were associated with protection of T1DM development. We did not find association between these variations with the age of onset of the disease and the presence of other autoimmune disorders. Our results suggest that SNPs in DC-SIGN promoter region can be associated to protection for T1DM in the Northeast Brazilian population.  相似文献   
36.
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   
37.

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   
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