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21.
Henrique Andrade R. Fonseca Magnus Gidlund Viviane Rodrigues SantAnna Esteferson Rodrigues Fernandes Francisco A. H. Fonseca Maria Cristina Izar 《Arquivos brasileiros de cardiologia》2021,116(4):844
Fundamento:Fatores de risco definidos para HIV e tradicionais podem estar associados a um aumento de eventos cardiovasculares. Estudos recentes sugerem que a resposta imune humoral à LDL modificada pode estar associada ao processo de aterosclerose.Objetivos:Avaliar a presença de anti-LDL oxidada e de peptídeos derivados da Apolipoproteína B no sangue, bem como sua associação à função endotelial na infecção por HIV.Métodos:Este estudo incluiu consecutivamente sujeitos com idade, sexo e dados demográficos correspondentes em dois grupos: (1) indivíduos infectados com HIV e naïve para terapia antiviral e (2) indivíduos não infectados. A aterosclerose subclínica foi avaliada pela espessura íntima-média, utilizando-se a ultrassonografia das artérias carótidas. A função endotelial foi determinada pela dilatação mediada por fluxo (DMF) da artéria braquial por ultrassonografia. Os níveis de autoanticorpos (IgM, IgG) de lipoproteínas de baixa densidade antioxidadas (LDL-ox), fragmentos de peptídeos antiapolipoproteína B (peptídeos ApoB-D e 0033G-Cys), e citocina foram avaliados por meio de ELISA.Resultados:Os resultados deste estudo não mostraram diferenças na aterosclerose subclínica entre os grupos. Entretanto, os sujeitos infectados com HIV apresentaram uma DMF mais baixa, em comparação com os sujeitos não infectados. Portanto, os sujeitos infectados com HIV apresentaram níveis mais altos de citocinas inflamatórias, títulos de IgG anti-LDL-ox, e IgG anti-ApoB-D. Em contraste, títulos de IgM anti-ApoB-D foram mais baixos em indivíduos infectados com HIV e associados a funções endoteliais diminuídas.Conclusões:Os resultados deste estudo mostram que a infecção por HIV, em sujeitos naïve, está associada à disfunção endotelial e à diminuição de anticorpos naturais para antígenos Apo-B. 相似文献
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To examine the possible in vivo significance of the immunomodulatory effects of vasoactive intestinal polypeptide described in vitro, several parameters of peripheral blood lymphocyte function were studied in a patient with a pancreatic endocrine tumor and high circulating levels of vasoactive intestinal polypeptide. There was no imbalance of the circulating lymphocyte subpopulations, and the in vitro responses of the patient's lymphocytes to mitogens were normal. However, there was an increased number (32%) of peripheral lymphocytes expressing interleukin 2 receptor. Serum immunoglobulin M levels were higher than in controls, and the patient's lymphocytes exhibited a spontaneous in vitro immunoglobulin M production higher than normal. Comparable increases in both interleukin 2 receptor expression and immunoglobulin M production were induced in vitro in normal peripheral lymphocyte cultures by the addition of vasoactive intestinal polypeptide concentrations similar to that detected in the patient's plasma. These findings indicate that a modulatory effect of vasoactive intestinal polypeptide on lymphocyte activation and immunoglobulin synthesis may be operating in vivo. They also suggest that vasoactive intestinal polypeptide does not mediate major defects in peripheral blood lymphocyte function in vivo. 相似文献
24.
Endoscopic implantation of a biopolymer in the lower esophageal sphincter for gastroesophageal reflux: a pilot study 总被引:9,自引:0,他引:9
Devière J Pastorelli A Louis H de Maertelaer V Lehman G Cicala M Le Moine O Silverman D Costamagna G 《Gastrointestinal endoscopy》2002,55(3):335-341
BACKGROUND: GERD is the most frequent disorder of the esophagus. Endoscopic minimally invasive treatment is desirable. However, the results of injection techniques have been disappointing. METHODS: A pilot study was conducted in patients with GERD, who required continuous therapy with a proton pump inhibitor, in which ethylene-vinyl-alcohol was injected into the muscle of the gastric cardia. Primary endpoints were the safety of the procedure, the effect on lower esophageal sphincter pressure and the stability of the injected material. A secondary endpoint was the effect on heartburn score after discontinuation of treatment with a proton pump inhibitor. RESULTS: Ethylene-vinyl-alcohol injection into the cardia resulted in circular diffusion of the product in 10 of 15 cases, suggesting that implantation into the muscle is feasible. Lower esophageal sphincter pressure was increased in 13 of 15 cases at 1 month and was sustained at a median follow-up of 6 months (range 4-12 months). Mean plus minus SEM of lower esophageal sphincter pressures (15 patients) were 12.2 plus minus 0.9, 18.7 plus minus 1.5 (p = 0.001 at baseline), and 16.7 plus minus 1.3 mm Hg (p = 0.038 from baseline) at, respectively, baseline, 1 month follow-up, and final follow-up. There was also a sustained reduction in heartburn score (off proton pump inhibitor) (3.40 plus minus 0.13 vs. 1.53 plus minus 0.24 and 1.87 plus minus 0.26 at baseline vs. 1 month and final follow-up, respectively; p < 0.01). Nine of the 15 patients had more than 50% of the injected material in place at second follow-up (at 6 months for 8 patients; at 12 months for 1 patient). In only 2 patients was there loss of more than 75% of injected ethylene-vinyl-alcohol. Persistence of greater than 50% of the material was associated with achievement of a circular injection. Only 4 patients had to resume therapy with a proton pump inhibitor. Mild retrosternal discomfort was observed in 8 patients; this disappeared in all cases after a maximum of 3 days. CONCLUSIONS: Ethylene-vinyl-alcohol implantation in the muscle of the cardia is feasible and safe. It leads to a sustained increase in resting lower esophageal sphincter pressure. This is associated with a sustained improvement in heartburn score for patients who previously required continuous therapy with a proton pump inhibitor. 相似文献
25.
Giovanni Pellegrino Tanguy Hedrich Viviane Sziklas JeanMarc Lina Christophe Grova Eliane Kobayashi 《Human brain mapping》2021,42(11):3352
Interactions between interictal epileptiform discharges (IEDs) and distant cortical regions subserve potential effects on cognition of patients with focal epilepsy. We hypothesize that “healthy” brain areas at a distance from the epileptic focus may respond to the interference of IEDs by generating inhibitory alpha and beta oscillations. We predict that more prominent alpha‐beta oscillations can be found in patients with less impaired neurocognitive profile. We performed a source imaging magnetoencephalography study, including 41 focal epilepsy patients: 21 with frontal lobe epilepsy (FLE) and 20 with mesial temporal lobe epilepsy. We investigated the effect of anterior (i.e., frontal and temporal) IEDs on the oscillatory pattern over posterior head regions. We compared cortical oscillations (5–80 Hz) temporally linked to 3,749 IEDs (1,945 frontal and 1,803 temporal) versus an equal number of IED‐free segments. We correlated results from IED triggered oscillations to global neurocognitive performance. Only frontal IEDs triggered alpha‐beta oscillations over posterior head regions. IEDs with higher amplitude triggered alpha‐beta oscillations of higher magnitude. The intensity of posterior head region alpha‐beta oscillations significantly correlated with a better neuropsychological profile. Our study demonstrated that cerebral cortex protects itself from IEDs with generation of inhibitory alpha‐beta oscillations at distant cortical regions. The association of more prominent oscillations with a better cognitive status suggests that this mechanism might play a role in determining the cognitive resilience in patients with FLE. 相似文献
26.
ObjectiveThe aim of the study was to investigate the effects of a novel polymerizable collagen cross-linker methacrylate-functionalized proanthocyanidins (MAPA) on the polymerization, microhardness and leaching of a HEMA-based experimental dental adhesive system.MethodsThree MAPAs were synthesized using different methacrylate (MA) to proanthocyanidins (PA) feeding ratios of 1:2, 1:1, and 2:1 to obtain MAPA-1, MAPA-2, and MAPA-3, respectively. The resulting three MAPAs and PA were added to an experimental adhesive formulated with HEMA and a tri-component photoinitiator system (0.5 wt% CQ/EDMAB/DPIHP) at 1%, 5% and 10% MAPA or PA concentrations (wt%). The adhesive polymerization kinetics was measured continuously in real-time for 10 min using a Fourier-transform infrared spectroscopy (FTIR) with an attenuated total reflectance (ATR) accessory. Degree of conversion (DC) and Vickers microhardness (MH) of cured adhesives were measured at 72 h post-cure. The leaching of cured adhesives in DI water was monitored using UV–vis spectrophotometer. Statistical analysis was performed using one-way and two-way ANOVA, Tukey’s (p < 0.05).ResultsThe adhesive formulations with 1%, 5% and 10% MAPAs-1, -2, -3 all generated higher rate of polymerization and 10-min DC than the formulations with PA at the same concentrations. At 72 h post-cure, the adhesive formulation with 5% MAPA-2 exhibited significantly higher DC (99.40%) and more than doubled MH (18.93) values than the formulation with 5% PA (DC = 89.47%, MH = 8.41) and the control (DC = 95.46%, MH = 9.33). Moreover, the cured adhesive with 5% MAPA-2 demonstrated significantly reduced PA leaching in comparison with cured adhesive with 5% PA.SignificanceSynthesized MAPA is a novel class of polymerizable collagen cross-linker that not only stabilizes dentin collagen via its PA component, but also improves polymerization, mechanical properties and stability of HEMA-based adhesives via its MA component. By inheriting the benefit while overcoming the drawback of PA, MAPA offers a revolutionary solution for improved bond-strength and longevity of dental restorations. 相似文献
27.
Salles Marcela Moreira Oliveira Viviane de Cássia Macedo Ana Paula do Nascimento Cássio Silva-Lovato Cláudia Helena Paranhos Helena de Freitas Oliveira 《Odontology / the Society of the Nippon Dental University》2021,109(1):284-294
Odontology - Evaluate, through a randomized clinical trial, the efficacy of brushing associated with oral irrigation in maintaining implant and overdenture hygiene. Thirty-eight participants, who... 相似文献
28.
de Siqueira Fabiana Suelen Figueredo Hilgemberg Bruna Araujo Lucila Cristina Rodrigues Hass Viviane Bandeca Matheus Coelho Gomes João Carlos Reis Alessandra Loguercio Alessandro D Cardenas Andres Felipe Millan 《Clinical oral investigations》2020,24(2):809-822
Clinical Oral Investigations - The aim of this study was to investigate the effects of collagen cross-linking agents on nanomechanical and bonding properties of eroded dentin (ED), 24 h... 相似文献
29.
Fernando H. Y. Cesena Viviane A. Valente Raul D. Santos Mrcio S. Bittencourt 《Arquivos brasileiros de cardiologia》2020,115(3):440
Background Differences between the updated versions of the Brazilian Guideline on Dyslipidemias and the American Heart Association (AHA)/American College of Cardiology (ACC) Cholesterol Guideline regarding cardiovascular risk stratification and statin eligibility are unknown.Objectives To compare cardiovascular risk categorization and statin eligibility based on the Brazilian guideline with those based on the AHA/ACC guideline in primary prevention patients.Methods We retrospectively analyzed individuals aged 40-74 years without high-risk conditions, with LDL-c 70 to < 190 mg/dL, not on lipid-lowering drugs, who underwent routine clinical assessment. Cardiovascular risk was stratified according to the Brazilian and the AHA/ACC guidelines. Subjects were considered eligible for statin therapy if LDL-c was at least 30 mg/dL above the target for the cardiovascular risk (Brazilian guideline) or the 10-year atherosclerotic cardiovascular disease risk was ≥7.5% (AHA/ACC guideline). A p-value < 0.05 was considered statistically significant.Results The study sample consisted of 18,525 subjects (69% male, age 48 ± 6 years). Among subjects considered at intermediate or high risk by the Brazilian guideline, over 80% would be in a lower risk category by the AHA/ACC guideline. Among men, 45% and 16% would be statin eligible by the Brazilian and the AHA/ACC guidelines criteria, respectively (p < 0.001). Among women, the respective proportions would be 16% and 1% (p < 0.001). Eighty-two percent of women and 57% of men eligible for statins based on the Brazilian guideline criterion would not be eligible according to the AHA/ACC guideline criterion.Conclusions Compared with the AHA/ACC guideline, the Brazilian guideline classifies a larger proportion of primary prevention patients into higher-risk categories and substantially increases statin eligibility. (Arq Bras Cardiol. 2020; 115(3):440-449) 相似文献