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91.

Background

Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.

Objective

To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.

Methods

In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.

Results

The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher''s Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher''s Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.

Conclusion

The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention.  相似文献   
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93.

Objectives

This study aimed to evaluate the systemic inflammatory response and cardiovascular changes induced by experimental periodontitis in rats.

Design

Experimental periodontitis was induced by placing a cotton ligature around the cervix of both sides of mandibular first molars and maxillary second molars in each male rat. Sham-operated rats had the ligature removed immediately after the procedure. Seven, 14 or 28 days after procedure, the effects of acetylcholine, sodium nitroprusside and phenylephrine were evaluated on blood pressure, aortic rings and isolated and perfused mesenteric bed. The blood was obtained for plasma Interleukin-6 (IL-6), C-reactive protein (CRP) and lipid evaluation. The mesenteric vessels were obtained to evaluate superoxide production and nitric oxide synthase 3 (NOS-3) expression.

Results

Ligature induced periodontitis reduced endothelium-dependent vasodilatation, a hallmark of endothelial dysfunction. This effect was associated with an increase in systemic inflammatory markers (IL-6 and CRP), worsens on lipid profile, increased vascular superoxide production and reduced NOS-3 expression. It is interesting to note that many of these effects were transitory.

Conclusion

Periodontitis induced a transient systemic and vascular inflammation which leads to endothelial dysfunction, an initial step for cardiovascular diseases. Moreover, the animal model of periodontitis used here may represent a valuable tool for studying the relationship between periodontitis and endothelial dysfunction.  相似文献   
94.

Objectives

The purpose of this study was to develop an adhesive resin with incorporation of niobium pentoxide and evaluate its properties.

Methods

Niobium pentoxide was characterised by X-ray diffraction, surface area, particle size, micro-Raman, scanning electron microscopy and the effectiveness of silanisation process by Fourier Transform Infrared (FTIR). An experimental adhesive resin was formulated with 0, 5, 10 and 20 wt% Nb2O5. The formulated adhesive resins were evaluated based on microhardness, degree of conversion, radiopacity and interface (resin/dentine) characterisation by micro-Raman.

Results

The particles used in this study presented a monoclinic crystalline phase with typical chemical groups and micrometre mean size. Microhardness and radiopacity increased with higher amounts of Nb2O5, and the particles were able to penetrate into the hybrid layers.

Conclusions

Therefore, Nb2O5 may be an alternative for polymer-based biomaterials.Clinical significance: Niobium pentoxide could be used to produce adhesive resins with enhanced properties.  相似文献   
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The BED capture enzyme immunoassay test makes it possible to determine whether individuals were recently infected with HIV.ObjectiveIn this study, the overall HIV and recent infections prevalences were determined at five Voluntary Counseling and Testing (VCT) centers, in the Metropolitan Region of Recife, Northeastern of Brazil.Material and methodsA cross-sectional study was conducted among users of five VCTs in the metropolitan region of Recife between July 2007 and April 2009. Out of the individuals who tested positive for HIV, 169 were analyzed to assess the prevalence of recent infection by means of the BED-CEIA (BED-Calypte®).ResultsOut of 46,696 individuals tested 916 (1.96%) turned out positive for HIV infection The highest prevalence was in Recife (3.9%). The prevalence was higher among males (3.93%), and men who have sex with men (MSM) (12.4%). The frequency of recent infections among the 169 subjects evaluated was 23.7%. Recent infections were more common among individuals under 25 years of age. There was slight predominance of men and higher frequency of heterosexuals in both groups, but still a significant portion of MSM (33%). Subtype B predominated, followed by a high proportion of subtype F.ConclusionsRecent infection occurs mainly among young individuals and heterosexuals, despite a significant proportion of recent infection among MSM. These results suggest that preventive actions aimed at the MSM community remains a challenge and efforts focusing this group should continue to be a priority.  相似文献   
100.
In measuring the quality of life of burn victims, it is essential that we find reliable and valid means. The Burn Sexuality Questionnaire (BSQ) is a specific instrument that assesses sexuality in the context of quality of life of burn victims. We set out to translate, validate and culturally adapt the BSQ into Brazilian Portuguese. The Portuguese version was applied to 80 patients. After translation, cultural adaptation was performed with 30 patients. We also tested the final version for reliability in 20 patients, and for face, content and construct validities in 30 patients, according to standard procedures. Total Cronbach's alpha was 0.87. Pearson's correlation was significant between scores for different time points. Construct validity was demonstrated with the correlation of the BSQ with the Burn Specific Health Scale – Revised (BSHS-R) questionnaire. It showed significant correlation between the BSQ social comfort domain and the BSHS-R affect and body image (p = 0.025), simple function ability (p = 0.008), work (p = 0.016) and treatment (p = 0.037) domains. This cultural adaptation of the BSQ suggests that it is a reliable tool and has construct validity for the social comfort domain. There is still need for a better-structured tool that could possibly evaluate functional and psychological aspects of sexuality, because one could easily overlook the psychosocial aspects of patients with major, complex burns.  相似文献   
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