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Objective: The aim of this study was to assess the endothelium function in patients with Turner syndrome using videocapillaroscopy and to compare the results with healthy control. Methods: Subjects and controls were studied in a temperature-controlled room, 20 days after no nailfold manipulations. The capillaries were visualized by a microscope connected to a television and a computer. The test of post-occlusive reactive hyperemia was performed using a sphygmomanometer attached to the fourth left finger, 20mmHg above maximum arterial pressure during 1 minute, and the following patterns were studied: area of transverse segment, maximal post-ischemia area and time to reach maximal post-ischemia area. Results: The value of measure of transverse segment projected area , the maximal postischemia area of hand nailfold capillary loops using computerized videophotometry and the time to reach maximal post ischemia area were studied in 40 patients with Turner syndrome and 26 healthy women controls of comparable age (20±7.5 versus 18±8.1 years old; p=0.57). There were differences between transverse segment area (706.8±139.1 versus 548.8±117.2; p=0.001). Maximal post-ischemia area (891.3±226.1 versus 643.5±134.3; p=0.001) and the time to reach it (10.8±4.3 versus 5.5±2.5; p=0.001) were different between patients and controls. Conclusions: Changes of capillary response to ischemia could be observed in patients with Turner syndrome using videocapillaroscopy when they were compared to a healthy control group.Keywords: Turner syndrome; microscopic angioscopy; endothelium. ResumoObjetivos: O objetivo deste estudo foi avaliar a função endotelial de pacientes com síndrome de Turner, utilizando a videocapilaroscopia e comparar os resultados com grupo controle saudável. Métodos: Pacientes e controles foram estudados em sala com temperatura controlada, após 20 dias, sem a manipulação das cutículas. Os capilares foram visualizados por microscópio conectado a televisão e computador. O teste de hiperemia reativa pós-oclusiva foi realizado utilizando-se esfigmomanômetro fixado no quarto quirodáctilo da mão esquerda, 20mmHg acima da pressão arterial máxima durante 1 minuto, e os seguintes parâmetros foram estudados: área do segmento transverso, área máxima pós-hiperemia e tempo para alcançar a área máxima pós-hiperemia. Resultados: O valor da área do segmento transverso, área máxima pós-hiperemia dos capilares da região da mão usando-se a videocapilaroscopia computadorizada e o tempo para alcançar a área pós-hiperemia foram estudadas em 40 pacientes com síndrome de Turner e 26 controles do sexo feminino pareados para idade (20±7,5 versus 18±8,1 anos; p=0,57). Houve diferenças nos grupos quanto à área do segmento transverso (706,8±139,1 versus 548,8±117,2; p=0,001). A área máxima pós-hiperemia (891,3±226,1 versus 643,5±134,3; p=0,001) e o tempo para alcançá-la (10,8±4,3 versus 5,5±2,5; p=0,001) foram significativamente diferentes entre pacientes e controles. Conclusão: Houve alterações na resposta do capilar à isquemia em pacientes...

Background Peripheral arterial tonometry (PAT) provides non-invasive measures of vascular health. Beneficial effects of metformin on vascular function have been reported in youth with type 1 diabetes (T1D). In the REducing with MetfOrmin Vascular Adverse Lesions (REMOVAL) trial in adults with T1D and high cardiovascular risk, we examined: (i) the extent to which routinely-measured cardiometabolic risk factors explain variance in baseline PAT; and (ii) the effects of metformin on PAT measures. Methods Cross-sectional univariable and multivariable analyses of baseline reactive hyperaemia index (RHI) and augmentation index (AI) (EndoPAT® (Itamar, Israel); and analysis of 36-months metformin versus placebo on vascular tonometry. Results In 364 adults ((mean ± SD) age 55.2 ± 8.5 years, T1D 34.0 ± 10.6 years, HbA1c 64.5 ± 9.0 mmol/mol (8.1 ± 0.8%)), RHI was 2.26 ± 0.74 and AI was 15.9 ± 19.2%. In an exhaustive search, independent associates of (i) RHI were smoking, waist circumference, systolic blood pressure and vitamin B12 (adjusted R2 = 0.11) and (ii) AI were male sex, pulse pressure, heart rate and waist circumference (adjusted R2 = 0.31). Metformin did not significantly affect RHI or AI. Conclusion Cardiometabolic risk factors explained only a modest proportion of variance in PAT measures of vascular health in adults with T1D and high cardiovascular risk. PAT measures were not affected by metformin.

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