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1.
《Revista portuguesa de cardiologia》2022,41(4):299-307
AimsMyocardial strain analysis enables more precise assessment of cardiac performance but is relatively load dependent. New tools have been developed with afterload adjustment. Our objective was to assess myocardial work (MW) in patients with repaired aortic coarctation (rACo).MethodsProspective study of consecutive patients with rACo who underwent a routine transthoracic echocardiogram in 2018 and 2019 at our center. Patients with significant aortic valve disease, pacemaker, or other congenital heart diseases (except for mild bicuspid aortic valve disease) were excluded. Global longitudinal strain with two dimensional speckle tracking analysis and MW were obtained (GWI:Global Work Index; GCW: Global Constructive Work; GWW: Global Wasted Work; GWE: Global Work Efficiency). Blood pressure was measured in the patient's right arm.ResultsWe included 42 patients in the analysis, mean age of 37±10 years, 38% males. In this group, 52% had hypertension and 64% had a concomitant bicuspid aortic valve. In comparison to previously published reference values, patients with rACo had significantly lower GWI (1807 vs. 1896 mmHg%) and GCW (2173 vs. 2232 mmHg%) (p<0.001), particularly in males. Systolic blood pressure is an independent predictor for GWI (β=0.432) and for GCW (β=0.534) and GLS an independent predictor of all MW parameters (β>0.594). Neither age nor gender were independent predictors.ConclusionsIn patients with rACo, there are some signs of left ventricular dysfunction with a reduction in GCW and GWI and with preserved GWE, despite normal ejection fraction and strain. 相似文献
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《Revista brasileira de otorrinolaringologia (English ed.)》2020,86(3):321-326
IntroductionMany studies have been done on proteomics, genomics, epigenetic, immunogenetics in many body fluids. Among these, circulating cell-free DNA (ccfDNA) entered the literature in 1948, but it has not been studied for many years due to technological deficiencies. Following recent advances, geno-metastasis has been mentioned and new research is needed in this area. ccfDNA is known to be an important biomolecule in this regard.ObjectiveThe presence of cell-free DNA in the circulatory system may offer a tremendous opportunity to provide novel biomarkers for thyroid diseases. This experimental study was conducted to determine the amount of ccfDNA in different thyroid diseases, then to evaluate whether the ccfDNA concentration varied between the disease groups and control group.MethodsIn total, we included 121 individuals in the present study. We collected blood samples and then determined the ccfDNA concentration in plasma of collected blood samples from three groups: thyroiditis (n = 33), benign (n = 37), and malignant (n = 30) and from a control group (n = 21).ResultsThe median values of the ccfDNA groups were found as 1610, 1665, 1685 and 576 ng/mL for the thyroiditis, benign, malign, and control groups, respectively. Findings showed that the ccfDNA of the three groups was significantly higher than the control (p < 0.0001). Each group was compared in terms of ccfDNA and the p-values of benign-thyroiditis, benign-malign, and thyroiditis-malign were 0.09, 0.65, and 0.29, respectively.ConclusionsThe clear differences between thyroid diseases and controls suggest that ccfDNA is worthy of attention as a biomarker for further evaluation of different thyroid diseases. Likewise, it might indicate a clear tendency that ccfDNA can also be used to distinguish different thyroid diseases. 相似文献
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Fúlvia Eduarda da Silva Tanit Ganz Sanchez 《Revista brasileira de otorrinolaringologia (English ed.)》2019,85(3):303-309
IntroductionMisophonia is characterized by the aversion to very selective sounds, which evoke a strong emotional reaction. It has been inferred that misophonia, as well as tinnitus, is associated with hyperconnectivity between auditory and limbic systems. Individuals with bothersome tinnitus may have selective attention impairment, but it has not been demonstrated in case of misophonia yet.ObjectiveTo characterize a sample of misophonic subjects and compare it with two control groups, one with tinnitus individuals (without misophonia) and the other with asymptomatic individuals (without misophonia and without tinnitus), regarding the selective attention.MethodsWe evaluated 40 normal-hearing participants: 10 with misophonia, 10 with tinnitus (without misophonia) and 20 without tinnitus and without misophonia. In order to evaluate the selective attention, the dichotic sentence identification test was applied in three situations: firstly, the Brazilian Portuguese test was applied. Then, the same test was applied, combined with two competitive sounds: chewing sound (representing a sound that commonly triggers misophonia), and white noise (representing a common type of tinnitus which causes discomfort to patients).ResultsThe dichotic sentence identification test with chewing sound, showed that the average of correct responses differed between misophonia and without tinnitus and without misophonia (p = 0.027) and between misophonia and tinnitus (without misophonia) (p = 0.002), in both cases lower in misophonia. Both, the dichotic sentence identification test alone, and with white noise, failed to show differences in the average of correct responses among the three groups (p ≥ 0.452).ConclusionThe misophonia participants presented a lower percentage of correct responses in the dichotic sentence identification test with chewing sound; suggesting that individuals with misophonia may have selective attention impairment when they are exposed to sounds that trigger this condition. 相似文献
5.
Ángel Becerra Héctor Trujillo Lucía Valencia Aurelio Rodríguez‐Pérez 《Brazilian Journal of Anesthesiology》2019,69(2):200-203
Background and objectives
A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.Case report
A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.Conclusion
Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma. 相似文献6.
《Revista brasileira de otorrinolaringologia (English ed.)》2019,85(5):642-663
IntroductionPossible associations between Zika virus infection and hearing loss were observed during the epidemic in the Americas.ObjectiveTo describe the auditory alterations, pathogenesis and recommendations for follow-up in individuals with prenatal or acquired Zika virus infection.MethodsBibliographic research conducted in March/2018–April/2019 at the main available databases. Article selection, data extraction and quality evaluation were carried out by two independent reviewers. Studies containing auditory evaluation of patients with congenital or acquired Zika virus infection; and/or hypotheses or evidences on the pathophysiology of auditory impairment associated with Zika virus; and/or recommendations on screening and follow-up of patients with auditory impairment by Zika virus were included.ResultsA total of 27 articles were selected. Sensorineural and transient hearing loss were reported in six adults with acquired Zika virus infection. Of the 962 studied children, 482 had microcephaly and 145 had diagnostic confirmation of Zika virus; 515 of the 624 children with auditory evaluation performed only screening tests with otoacoustic emissions testing and/or automated click-stimuli auditory brainstem response testing. Studies in prenatally exposed children were very heterogeneous and great variations in the frequency of altered otoacoustic emissions and automated click-stimuli auditory brainstem response occurred across the studies. Altered otoacoustic emissions varied from 0% to 75%, while altered automated click-stimuli auditory brainstem response varied from 0% to 29.2%. Sensorineural, retrocochlear or central origin impairment could not be ruled out. One study with infected mice found no microscopic damage to cochlear hair cells. Studies on the pathogenesis of auditory changes in humans are limited to hypotheses and recommendations still include points of controversy.ConclusionThe available data are still insufficient to understand the full spectrum of the involvement of the auditory organs by Zika virus, the pathogenesis of this involvement or even to confirm the causal association between auditory involvement and virus infection. The screening and follow-up recommendations still present points of controversy. 相似文献
7.
《Revista brasileira de otorrinolaringologia (English ed.)》2015,81(4):384-388
IntroductionIndividuals with the same ability of speech recognition in quiet can have extremely different results in noisy environments.ObjectiveTo standardize speech perception in adults with normal hearing in the free field using the Brazilian Hearing in Noise Test.MethodsContemporary, cross-sectional cohort study. 79 adults with normal hearing and without cognitive impairment participated in the study. Lists of Hearing in Noise Test sentences were randomly in quiet, noise front, noise right, and noise left.ResultsThere were no significant differences between right and left ears at all frequencies tested (paired t − 1 test). Nor were significant differences observed when comparing gender and interaction between these conditions. A difference was observed among the free field positions tested, except in the situations of noise right and noise left.ConclusionResults of speech perception in adults with normal hearing in the free field during different listening situations in noise indicated poorer performance during the condition with noise and speech in front, i.e., 0°/0°. The values found in the standardization of the Hearing in Noise Test free field can be used as a reference in the development of protocols for tests of speech perception in noise, and for monitoring individuals with hearing impairment. 相似文献
8.
目的:探讨小檗碱对人乳腺癌细胞MDA-MB-231体外生长的影响及其与PPAR-y受体的关系.方法:采用噻唑蓝(MTT)法检测小檗碱对MDA-MB-231细胞的生长抑制效应;TUNEL法检测细胞凋亡;联合PPAR-γ拮抗剂GW9662,分析小檗碱对MDA-MB-231细胞增殖的影响与PPARγ受体的关系.结果:小檗碱呈量-效和时-效关系抑制MDA-MB-231细胞生长,24 h的半数抑制浓度(IC50)为0.21μmol/L;小檗碱诱导MDA-MB-231细胞凋亡作用随药物浓度的增加而增强;PPARγ受体拮抗剂不能逆转小檗碱对细胞增殖的抑制作用.结论:小檗碱可明显抑制MDA-MB-231细胞生长并诱导其凋亡,但其作用不通过PPAR受体介导. 相似文献
9.
Adult-onset rod disease with abundant intranuclear rods 总被引:2,自引:0,他引:2
Summary The third case of adult-onset rod disease (nemaline myopathy) with abundant myofibrillar as well as intranuclear rods is described. The 61-year-old woman suffered from progressive weakness of proximal extremities and of the neck, mimicking polymyositis. Muscle biopsy revealed a striking myopathic pattern, with intranuclear rods occurring in 31% of the fibres. On light and electron microscopy and by immunohistochemical study, the rods differed from myofibrillar rods. The absence of -actinin in intranuclear rods suggests an enhanced readiness of actin filaments to bind to diverse proteins, instead of overproduction of -actinin as the pathogenetic basis of the rod formation. 相似文献
10.
目的:研究重组小鼠干细胞逆转录病毒载体介导基因转染,探索一条高效基因转染的途径,为重组小鼠干细胞逆转录病毒载体在基因转染中的应用提供理论依据和奠定实验基础。方法:①逆转录病毒载体的构建:EC1-4(repeats1-4ofcadherin-5extracellulardomains)基因克隆产物和mutant(Ser222A)MEK1基因克隆产物,Bg1Ⅱ和EcoRⅠ限制性内切核酸酶切割后,克隆进入逆转录病毒表达载体pMSCV。②CD41+细胞的获取和细胞培养:从脐带血分离的CD34+细胞通过TPO诱导表达CD41,FACS分离CD41+细胞。高糖DMEM培养液培养NIH3T3和MDA-MB-435细胞,U937细胞培养在RPMI-1640培养液,UT7细胞是细胞因子依赖性细胞株,Iscove'smodifiedDulbeco's培养液中加入GM-CSF。③测定病毒滴度:逆转录病毒载体转入包装细胞293,36h后收集病毒上清液,感染NIH3T3细胞,流式细胞仪测定病毒滴度。④Westernblot:基因转染CD41+、UT7、U937和MDA-MB-435细胞,Westernblot检测基因产物的表达。结果:293细胞产生高滴度MEK1pMSCV病毒:3.1×107,高滴度EC1-4pMSCV病毒:1.0×108。用稀释8倍的病毒转染基因,重组逆转录病毒MEK1pMSCV转染白血病细胞株UT7和U973,GFP阳性细胞(转染阳性细胞)分别是60.73%、72.56%。重组逆转录病毒MEK1pMSCV转染原代培养细胞CD41+,GFP阳性细胞为30.57%。重组逆转录病毒EC1-4pMSCV转染人乳腺癌细胞株MDA-MB-435,GFP阳性细胞为97.54%。TPO作用CD41+和UT7细胞以及血清对U973细胞的作用,显示出外源mutationMEK基因的dominantnegative的效应,实验组磷酸化的MEK1减少。EC1-4基因转染的MDA-MB-435细胞表达了EC1-4基因产物。结论:重组小鼠干细胞逆转录病毒载体能高效基因转染CD41+、UT7、U937和MDA-MB-435细胞,转染的基因能稳定地表达。 相似文献