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Introduction:

In patients with severe aortic stenosis, low-gradient, low-flow and preserved ejection fraction (≥ 50%) (LG/LFp) the decrease in stroke volume index (Svi) could be due to diminished contractility. The aim of this study was to analyze if low Svi in patients with LG/LFp is related to a decrease in contractility.

Methods:

Thirty patients with LF/LGp and 63 normal subjects were studied with Doppler echocardiography. The level of contractility (LC) was assessed by mean of midwall shortening fraction (mSF) – end-systolic stress (ESS) relationship. Relative wall thickness (RWT) and aortic valve area (AVA) were calculated.

Results:

LC was diminished in 40% of LF/LGp patients. By bivariate analysis LC correlated with RWT and mSF. Svi correlated with AVA but not with LC. In multiple linear regression RWT and mSF were predictors independents of LC. About Svi, AVA was the only predictor independent variable.

Conclusion:

Decreased contractility was present in 40% of LF/LGp patients despite preserved ejection fraction. LC had correlation with mSF and EPR. Low Svi appears to be related to aortic stenosis severity rather than low contractility.Key words: Aortic stenosis, Contractility, Echocardiography, Ventricular function  相似文献   
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IntroductionChronic Eustachian tube dysfunction can cause several symptoms and middle ear conditions that can impact patient quality of life. It is estimated to be relatively frequent, affecting approximately 5% of adults. The diagnostic tools for this condition are still inadequate. In 2012, McCoul et al. published a questionnaire for the evaluation of Eustachian tube dysfunction named ETDQ-7. They established its replicability and validity. The cutoff point for the diagnosis of chronic Eustachian tube dysfunction was equal to or greater than 14.5, with 100% sensitivity and 100% specificity.ObjectiveTo translate, adapt and validate the ETDQ-7 questionnaire to Brazilian Portuguese.MethodsWe translated the questionnaire into Brazilian Portuguese and applied it to 50 patients, 20 of whom had chronic Eustachian tube dysfunction, and 30 controls.ResultsThe results obtained with the North-American questionnaire were confirmed in its Brazilian version. The cut-off point for the diagnosis of chronic Eustachian tube dysfunction was ≥14, also exhibiting high sensitivity and specificity, very similar to that of ETDQ-7.ConclusionIt is recommended that ETDQ-7 be used to complement the clinical history of patients with chronic Eustachian tube dysfunction; it can also be used as an important tool for diagnosis, patient follow-up and treatment management.  相似文献   
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Background Both the safety and efficacy of biologic therapy may be affected in the presence of highly prevalent chronic viral hepatitis. Objectives To evaluate the safety and effectiveness of ustekinumab and antitumour necrosis factor therapy in patients with psoriasis and concomitant chronic viral hepatitis. Methods This was a retrospective, multicentre study. Twenty‐five patients with psoriasis and concurrent hepatitis C virus (HCV) (20 patients) or hepatitis B virus (HBV) (five patients) infection who had received at least one biologic agent (etanercept, 21 treatments; adalimumab, four; ustekinumab, four; infliximab, two) were included. Clinical, imaging and laboratory data were recorded. Results In the case of HCV infection, the majority of the patients did not exhibit increases in their viral load or serum liver tests. Aspartate aminotransferase, alanine aminotransferase and gamma glutamyl transpeptidase were doubled from the baseline measurement in only one patient treated with etanercept. Two other cases exhibited viral load increases during the follow‐up period. In total, 18 of the 26 treatments achieved a 75% improvement in their Psoriasis Area and Severity Index (PASI 75) score during the follow‐up period. Two patients treated with etanercept were diagnosed with hepatocellular carcinoma. In the case of HBV infection, all of the patients were being treated with antiviral therapy, and none presented significant variations in viral load or serum liver enzymes. All patients achieved a PASI 75 during follow‐up. Conclusions Biologic therapy was effective and safe for the majority of our patients with HCV and HBV infection, although there may be a risk of reactivation or aggravation. We describe the first cases to receive ustekinumab. The use of biologics should be limited to those cases in which the risk–benefit ratio is justified.  相似文献   
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Chronic cellular stress associated with neurodegenerative disease can result in the persistence of stress granule (SG) structures, membraneless organelles that form in response to cellular stress. In Huntington’s disease (HD), chronic expression of mutant huntingtin generates various forms of cellular stress, including activation of the unfolded protein response and oxidative stress. However, it has yet to be determined whether SGs are a feature of HD neuropathology. We examined the miRNA composition of extracellular vesicles (EVs) present in the cerebrospinal fluid (CSF) of patients with HD and show that a subset of their target mRNAs were differentially expressed in the prefrontal cortex. Of these targets, SG components were enriched, including the SG-nucleating Ras GTPase-activating protein-binding protein 1 (G3BP1). We investigated localization and levels of G3BP1 and found a significant increase in the density of G3BP1-positive granules in the cortex and hippocampus of R6/2 transgenic mice and in the superior frontal cortex of the brains of patients with HD. Intriguingly, we also observed that the SG-associated TAR DNA-binding protein 43 (TDP43), a nuclear RNA/DNA binding protein, was mislocalized to the cytoplasm of G3BP1 granule–positive HD cortical neurons. These findings suggest that G3BP1 SG dynamics may play a role in the pathophysiology of HD.  相似文献   
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