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71.
BackgroundEchocardiography is essential for the diagnosis and quantification of aortic regurgitation (AR). Velocity-time integral (VTI) of AR flow could be related to AR severity.ObjectiveThis study aims to assess whether VTI is an echocardiographic marker of AR severity.MethodsWe included all patients with moderate or severe native AR and sinus rhythm who visited our imaging laboratory from January to October 2016. All individuals underwent a complete echocardiogram with AR VTI measurement. The association between VTI and AR severity was analyzed by logistic regression and multivariate regression models. A p-value<0,05 was considered statistically significant.ResultsAmong the 62 patients included (68.5±14.9 years old; 64.5%: moderate AR; 35.5%: severe AR), VTI was higher in individuals with moderate AR compared to those with severe AR (2.2±0.5 m vs. 1.9±0.5 m, p=0.01). Patients with severe AR presented greater values of left ventricular end-diastolic diameter (LVEDD) (56.1±7.1 mm vs. 47.3±9.6 mm, p=0.001), left ventricular end-diastolic volume (LVEDV) (171±36.5 mL vs. 106±46.6 mL, p<0.001), effective regurgitant orifice (0.44±0.1 cm2vs. 0.18±0.1 cm2, p=0.002), and regurgitant volume (71.3±25.7 mL vs. 42.5±10.9 mL, p=0.05), as well as lower left ventricular ejection fraction (LVEF) (54.1±11.2% vs. 63.2±13.3%, p=0.012). The VTI proved to be a marker of AR severity, irrespective of LVEDD, LVEDV, and LVEF (odds ratio 0.160, p=0.032) and of heart rate and diastolic blood pressure (DBP) (odds ratio 0.232, p=0.044).ConclusionsThe VTI of AR flow was inversely associated with AR severity regardless of left ventricular diameter and volume, heart rate, DBP, and LVEF. VTI could be a marker of AR severity in patients with native AR and sinus rhythm. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
72.
Summary Two 5 g glucose loads at 1-h interval were given to healthy controls and obese subjects with slightly altered or normal OGTT in order to explore the capacity of restoration of the ‘rapid insulin response’ to i.v. glucose. In the normal subjects, the two successive loads gave rise to identical responses as far as maximum increase (Δmax), average increase at 2–5 min (Δ2–5 min), area of increase 0–15 min (Δ0–15 min) for both glucose and IRI, were concerned. Obese subjects could be divided on the basis of their insulin response to the first load into normal responders (group I) and high-responders (group II). In group I obese subjects, the responses to the second load were identical to those to the first. In group II obese subjects Δmax, Δ2–5 min and Δ0–15 min of the insulin response to the second load were reduced as compared to the first.  相似文献   
73.
Leptospirosis is a common disease in tropical countries, and the kidney is one of the main target organs. Membrane proteins of Leptospira are capable of causing endothelial damage in vitro, but there have been no studies in humans evaluating endothelial glycocalyx damage and its correlation with acute kidney injury (AKI). We performed a cohort study in an outbreak of leptospirosis among military personnel. AKI was diagnosed in 14 of 46 (30.4%) patients. Leptospirosis was associated with higher levels of intercellular adhesion molecule-1 (ICAM-1; 483.1 ± 31.7 versus 234.9 ± 24.4 mg/L, P < 0.001) and syndecan-1 (73.7 ± 15.9 versus 21.2 ± 7.9 ng/mL, P < 0.001) compared with exposed controls. Patients with leptospirosis-associated AKI had increased level of syndecan-1 (112.1 ± 45.4 versus 41.5 ± 11.7 ng/mL, P = 0.021) and ICAM-1 (576.9 ± 70.4 versus 434.9 ± 35.3, P = 0.034) compared with leptospirosis patients with no AKI. Association was verified between syndecan-1 and ICAM-1 with serum creatinine elevation and neutrophil gelatinase-associated lipocalin (NGAL) levels. This association remained even after multivariate analysis including other AKI-associated characteristics. Endothelial injury biomarkers are associated with leptospirosis-associated renal damage.  相似文献   
74.
Rift Valley fever (RVF) is a viral zoonotic disease occurring throughout Africa, the Arabian Peninsula, and Madagascar. The disease is caused by a Phlebovirus (RVF virus [RVFV]) transmitted to vertebrate hosts through the bite of infected mosquitoes. In Madagascar, the first RVFV circulation was reported in 1979 based on detection in mosquitoes but without epidemic episode. Subsequently, two outbreaks occurred: the first along the east coast and in the central highlands in 1990 and 1991 and the most recent along the northern and eastern coasts and in the central highlands in 2008 and 2009. Despite the presence of 24 mosquitoes species potentially associated with RVFV transmission in Madagascar, little associated entomological information is available. In this review, we list the RVFV vector, Culex antennatus, as well as other taxa as candidate vector species. We discuss risk factors from an entomological perspective for the re-emergence of RVF in Madagascar.  相似文献   
75.
76.
This study analyzed the relations and time-related changes in eligibility for cardiac resynchronization therapy and prophylactic defibrillator implantation in 161 potential candidates for heart transplantation. Although up to 62% of patients who fulfilled the severity criteria for heart transplantation were eligible for either device, this percentage increased as clinical/instrumental parameters of heart failure severity worsened.  相似文献   
77.
The field of assisted reproductive technology is shaped and changed constantly by advances in science and cutting-edge innovations. In a quest to maximise outcomes, add-on interventions are often adopted and utilised prematurely while the principles of evidence-based medicine seem to be less strictly adhered to. In this review we will attempt to summarise the latest evidence about some of the adjuvants.  相似文献   
78.
79.
Background: Tidal expiratory flow limitation (EFL) is a step of paramount importance in the functional decline in COPD. Among mechanisms contributing to EFL, loss of airway-parenchymal interdependence could mostly be involved. Aim: To assess if EFL is a functional marker more frequently linked to prevalent pulmonary emphysema rather than to prevalent chronic bronchiolitis in COPD patients with moderate-to-severe airflow obstruction. Methods: Forty consecutive stable COPD patients with FEV1 between 59 and 30% of predicted were functionally evaluated by measuring spirometry, maximal flow-volume curve and lung diffusion capacity (DLCO) and coefficient of diffusion (KCO). EFL was assessed by the negative expiratory pressure (NEP) method both in sitting and supine position. Chronic dyspnea was also scored by modified Medical Research Council (mMRC) scale. Results: In sitting position 13 patients (33%) were flow limited (FL) and 27 were non-flow limited (NFL). Only FEV1/FVC, FEV1 and MEF25–75% were different between FL and NFL patients (p < 0.01). In supine position, however, among NFL patients in sitting position those who developed EFL, had significantly lower values of DLCO and KCO (p < 0.05) and higher mMRC score (p < 0.01), but similar values of FEV1 as compared to those who did not have EFL. Conclusions: In COPD EFL in sitting position is highly dependent by the severity of airflow obstruction. In contrast, the occurrence of EFL in supine position is associated with worse DLCO and KCO and greater chronic dyspnea, reflecting a prevalent emphysematous phenotype in moderate-to-severe COPD patients.  相似文献   
80.
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