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1.
Catheter Cardiovasc Interv ; 88(6): 953-960, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27143093

RESUMO

BACKGROUND: Alcohol septal ablation (ASA) is an alternative treatment for symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients refractory to pharmacological therapy. We sought to evaluate the immediate and long-term incidence of death and changes in life quality in a consecutive cohort submitted to ASA. METHODS AND RESULTS: Between October 1998 and December 2013, a total of 56 patients (mean age 53.2 ± 15.5) with symptomatic refractory HOCM were treated with ASA and followed during 15 years (mean 8 ± 4 years). There were 7 (12.5%) deaths, 2 (3.6%) being of cardiac cause. The Kaplan-Meier survival probability estimate was 96.4% at 1 year, 87.7 at 5 years and 81.0% at 12 years post-ASA. Significant improvement was observed in life quality assessed by DASI index and NYHA functional class as well as in the left ventricle outflow tract (LVOT) gradient reduction (from 92.8 ± 3.3 mm Hg to 9.37 ± 6.7 mm Hg, P < 0.001) and septum thickness (from 23.9 ± 0.6 mm to 12.9 ± 1.0 mm, P < 0.001). Only one patient (1.7%) required permanent pacemaker immediately after ASA. During follow-up, one patient had a repeated ASA, three patients underwent myectomy and other four required ICD/pacemaker. In the multivariate model only post-ASA LVOT residual gradient and left ventricle mass were associated with worse prognosis. CONCLUSIONS: In this long-term clinical follow-up without losses, ASA was effective in improving quality of life and NYHA functional class, with relatively low mortality and very low need for immediate permanent pacemaker implantation. © 2016 Wiley Periodicals, Inc.


Assuntos
Técnicas de Ablação/métodos , Cateterismo Cardíaco/métodos , Cardiomiopatia Hipertrófica/cirurgia , Etanol/administração & dosagem , Septos Cardíacos , Brasil/epidemiologia , Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/mortalidade , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento
2.
Trials ; 25(1): 481, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014430

RESUMO

BACKGROUND: In standard weaning from mechanical ventilation, a successful spontaneous breathing test (SBT) consisting of 30 min 8 cmH2O pressure-support ventilation (PSV8) without positive end-expiratory pressure (PEEP) is followed by extubation with continuous suctioning; however, these practices might promote derecruitment. Evidence supports the feasibility and safety of extubation without suctioning. Ultrasound can assess lung aeration and respiratory muscles. We hypothesize that weaning aiming to preserve lung volume can yield higher rates of successful extubation. METHODS: This multicenter superiority trial will randomly assign eligible patients to receive either standard weaning [SBT: 30-min PSV8 without PEEP followed by extubation with continuous suctioning] or lung-volume-preservation weaning [SBT: 30-min PSV8 + 5 cmH2O PEEP followed by extubation with positive pressure without suctioning]. We will compare the rates of successful extubation and reintubation, ICU and hospital stays, and ultrasound measurements of the volume of aerated lung (modified lung ultrasound score), diaphragm and intercostal muscle thickness, and thickening fraction before and after successful or failed SBT. Patients will be followed for 90 days after randomization. DISCUSSION: We aim to recruit a large sample of representative patients (N = 1600). Our study cannot elucidate the specific effects of PEEP during SBT and of positive pressure during extubation; the results will show the joint effects derived from the synergy of these two factors. Although universal ultrasound monitoring of lungs, diaphragm, and intercostal muscles throughout weaning is unfeasible, if derecruitment is a major cause of weaning failure, ultrasound may help clinicians decide about extubation in high-risk and borderline patients. TRIAL REGISTRATION: The Research Ethics Committee (CEIm) of the Fundació Unió Catalana d'Hospitals approved the study (CEI 22/67 and 23/26). Registered at ClinicalTrials.gov in August 2023. Identifier: NCT05526053.


Assuntos
Extubação , Pulmão , Estudos Multicêntricos como Assunto , Respiração com Pressão Positiva , Desmame do Respirador , Humanos , Desmame do Respirador/métodos , Respiração com Pressão Positiva/métodos , Respiração com Pressão Positiva/efeitos adversos , Pulmão/fisiopatologia , Pulmão/diagnóstico por imagem , Medidas de Volume Pulmonar , Ultrassonografia , Resultado do Tratamento , Masculino , Fatores de Tempo , Feminino , Adulto , Pessoa de Meia-Idade , Respiração Artificial/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Idoso , Sucção/métodos , Estudos de Equivalência como Asunto
3.
Ann Noninvasive Electrocardiol ; 18(4): 311-26, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23879271

RESUMO

The electrocardiogram is an important tool for the initial diagnostic suspicion of hypertrophic cardiomyopathy in any of its forms, both in symptomatic and in asymptomatic patients because it is altered in more than 90 percent of the cases. Electrocardiographic anomalies are more common in patients carriers of manifest hypertrophic cardiomyopathy and the electrocardiogram alterations are earlier and more sensitive than the increase in left ventricular wall thickness detected by the echocardiogram. Nevertheless, despite being the leading cause of sudden death among young competitive athletes there is no consensus over the need to include the method in the pre-participation screening. In apical hypertrophic cardiomyopathy the electrocardiographic hallmarks are the giant negative T waves in anterior precordial leads. In the vectorcardiogram, the QRS loop is located predominantly in the left anterior quadrant and T loop in the opposite right posterior quadrant, which justifies the deeply negative T waves recorded. The method allows estimating the left ventricular mass because it relates to the maximal spatial vector voltage of the left ventricle in the QRS loop. The recording on electrocardiogram or Holter monitoring of nonsustained monomorphic ventricular tachycardia in patients with syncope, recurrent syncope in young patient, hypotension induced by strain, bradyarrhythmia, or concealed conduction are markers of poor prognosis. The presence of rare sustained ventricular tachycardia is observed in mid-septal obstructive HCM with apical aneurysm. The presence of complete right bundle branch block pattern is frequent after the percutaneous treatment and complete left bundle branch block is the rule after myectomy.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/epidemiologia , Vetorcardiografia/métodos , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Eletrocardiografia/métodos , Feminino , Humanos , Lactente , Masculino , Prevalência , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto Jovem
4.
Front Immunol ; 13: 901872, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248801

RESUMO

Intravenous immunoglobulin (IVIg) is used as treatment for several autoimmune and inflammatory conditions, but its specific mechanisms are not fully understood. Herein, we aimed to evaluate, using systems biology and artificial intelligence techniques, the differences in the pathophysiological pathways of autoimmune and inflammatory conditions that show diverse responses to IVIg treatment. We also intended to determine the targets of IVIg involved in the best treatment response of the evaluated diseases. Our selection and classification of diseases was based on a previously published systematic review, and we performed the disease characterization through manual curation of the literature. Furthermore, we undertook the mechanistic evaluation with artificial neural networks and pathway enrichment analyses. A set of 26 diseases was selected, classified, and compared. Our results indicated that diseases clearly benefiting from IVIg treatment were mainly characterized by deregulated processes in B cells and the complement system. Indeed, our results show that proteins related to B-cell and complement system pathways, which are targeted by IVIg, are involved in the clinical response. In addition, targets related to other immune processes may also play an important role in the IVIg response, supporting its wide range of actions through several mechanisms. Although B-cell responses and complement system have a key role in diseases benefiting from IVIg, protein targets involved in such processes are not necessarily the same in those diseases. Therefore, IVIg appeared to have a pleiotropic effect that may involve the collaborative participation of several proteins. This broad spectrum of targets and 'non-specificity' of IVIg could be key to its efficacy in very different diseases.


Assuntos
Doenças Autoimunes , Imunoglobulinas Intravenosas , Inteligência Artificial , Doenças Autoimunes/tratamento farmacológico , Proteínas do Sistema Complemento , Humanos , Biologia de Sistemas
5.
Catheter Cardiovasc Interv ; 76(5): 719-23, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20799353

RESUMO

We report an eight-year-old child presented with classical features of hypertrophic obstructive cardiomyopathy and with New York Heart Association (NYHA) class III symptoms, eight months after myectomy and refractory to medical treatment. Cardiac transplantation was indicated due to the severity of symptoms. But the lymphocyte reaction test showed almost 100% reaction of antibodies, and the surgeons rejected the heart transplantation for fear of hyperacute rejection. Then an alcohol septal ablation (ASA) was proposed, which was successfully performed on August 17, 2005. The post-extrasystolic gradient was reduced from 160 to 60 mm Hg immediately and no other complications were seen. The child is being followed since then and echocardiography changes include a further reduction of septum thickness and gradient (P = 0.001), and important symptoms relieved after 3.5 years of follow up. ASA may be an option to be considered in children with critical hypertrophic obstructive cardiomyopathy in NYHA functional class III/IV, when other methods of treatment failed. © 2010 Wiley-Liss, Inc.


Assuntos
Técnicas de Ablação , Procedimentos Cirúrgicos Cardíacos , Cardiomiopatia Hipertrófica/terapia , Etanol/administração & dosagem , Insuficiência Cardíaca/terapia , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Cardiomiopatia Hipertrófica/cirurgia , Criança , Contraindicações , Ecocardiografia Doppler em Cores , Eletrocardiografia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Humanos , Masculino , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Falha de Tratamento , Função Ventricular
6.
Eur Biophys J ; 38(4): 503-22, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19189102

RESUMO

In a previous work we observed multilayered plate-like structures surrounding partially denatured HeLa chromosomes at metaphase ionic conditions. This unexpected finding has led us to carry out an extensive investigation of these structures. Our results show that plates can also be found in metaphase chromosomes from chicken lymphocytes. We have used atomic force microscopy (AFM) to image and investigate the mechanical properties of plates in aqueous solution. Plates are thin (approximately 6.5 nm each layer) but compact and resistant to penetration by the AFM tip: their Young's modulus is approximately 0.2 GPa and the stress required for surface penetration is approximately 0.03 GPa in the presence of Mg(2+) (5-20 mM). Low-ionic strength conditions produce emanation of chromatin fibers from the edges of uncrosslinked plates. These observations and AFM results obtained applying high forces indicate that the chromatin filament is tightly tethered inside the plates. Images of metal-shadowed plates and cryo-electron microscopy images of frozen-hydrated plates suggest that nucleosomes are tilted with respect to the plate surface to allow an interdigitation between the successive layers and a thickness reduction compatible with the observed plate height. The similarities between denatured plates from chicken chromosomes and aggregates of purified chromatin from chicken erythrocytes suggest that chromatin has intrinsic structural properties leading to plate formation. Scanning electron micrographs and images obtained with the 200-kV transmission microscope show that plates are the dominant component of compact chromatids. We propose that metaphase chromosomes are formed by many stacked plates perpendicular to the chromatid axis.


Assuntos
Cromossomos Humanos/ultraestrutura , Cromossomos/ultraestrutura , Metáfase , Animais , Galinhas , Cromatina/ultraestrutura , Microscopia Crioeletrônica , Elasticidade , Eritrócitos , Células HeLa , Humanos , Linfócitos , Magnésio , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nucleossomos/ultraestrutura , Propriedades de Superfície
7.
J Intensive Care ; 6: 74, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473793

RESUMO

BACKGROUND: High red blood cell distribution width (RDW) is associated with worse outcome in diverse scenarios, including in critical illness. The Sabadell score (SS) predicts in-hospital survival after ICU discharge. We aimed to determine RDW's association with survival after ICU discharge and whether RDW can improve the accuracy of the SS. DESIGN: Retrospective cohort study. Setting: general ICU at a university hospital. PATIENTS: We included all patients discharged to wards from January 2010 to October 2016. METHODS: We analyzed associations between RDW and variables recorded on admission (age, comorbidities, severity score), during the ICU stay (treatments, complications, length of stay (LOS)), and at ICU discharge (SS). The primary outcome was hospital mortality. Statistical analysis included multivariable logistic regression and receiver operating characteristic curve (ROC) analyses. RESULTS: We discharged 3366 patients to wards; median ward LOS was 7 [4-13] days; ward mortality was 5.2%. Mean RDW at ICU discharge was 15.4 ± 2.5%. Ward mortality was higher at each quartile of RDW (0.7%, 2.9%, 7.5%, 10.3%; area under ROC 0.81). A logistic regression model with Sabadell score obtained an excellent accuracy for ward mortality (area under ROC 0.863), and the addition of RDW slightly improved accuracy (AUROC 0.890, p < 0.05). Recursive partitioning demonstrated higher mortality in patients with high RDW at each SS level (1.6% vs. 0.3% in SS0, 9.7% vs. 1.1% in SS1, 21.9% vs. 9.7% in SS2), but not in SS3. CONCLUSION: High RDW is a marker of severity at ICU discharge and improves the accuracy of Sabadell score in predicting ward mortality except in the more extreme SS3.

8.
Ther Adv Respir Dis ; 12: 1753466618787385, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30014774

RESUMO

BACKGROUND: The excessive retention of sputum in the airways, leading to pulmonary infections, is a common consequence of bronchiectasis. Although inhalation of 7% hypertonic saline (HS) has proven an effective method to help remove the mucus, many patients are intolerant of this treatment. The addition of 0.1% hyaluronic acid to HS (HS+HA) could increase tolerance to HS in these patients. The main objective of this study was to evaluate the tolerability of HS+HA in bronchiectasis patients who are intolerant to HS. METHODS: This prospective, observational, open-label study analysed the outcomes of two groups of bronchiectasis patients previously scheduled to start HS therapy. Patients were assessed for tolerance to HS by a questionnaire, spirometry and clinical evaluation. Patients who were intolerant were evaluated for tolerance to HS+HA approximately one week later. All patients were evaluated for their tolerance to HS or HS+HA 4 weeks after the start of their treatment. Patients were also assessed with quality-of-life and adherence questionnaires, and all adverse events were registered. RESULTS: A total of 137 bronchiectasis patients were enrolled in the study (age = 63.0 ± 14.7 years; 63.5% women). Of these, 92 patients (67.1%) were tolerant and 45 patients (32.9%) were intolerant to HS. Of the 45 patients intolerant to HS, 31 patients (68.9%) were tolerant and 14 patients (31.1%) intolerant to HS+HA. Of these 31 tolerant patients, 26 (83.9%) could complete the 4-week treatment with HS+HA. CONCLUSIONS: Two-thirds of bronchiectasis patients that presented intolerance to inhaled HS alone are tolerant to inhaled HS+HA, suggesting that HA improves tolerance to HS therapy.


Assuntos
Bronquiectasia/terapia , Ácido Hialurônico/administração & dosagem , Pulmão/fisiopatologia , Depuração Mucociliar , Solução Salina Hipertônica/administração & dosagem , Escarro , Administração por Inalação , Idoso , Bronquiectasia/diagnóstico , Bronquiectasia/fisiopatologia , Feminino , Humanos , Ácido Hialurônico/efeitos adversos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Solução Salina Hipertônica/efeitos adversos , Espanha , Resultado do Tratamento
9.
J Intensive Care ; 6: 24, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29686878

RESUMO

PURPOSE: To determine the frequency of limitations on life support techniques (LLSTs) on admission to intensive care units (ICU), factors associated, and 30-day survival in patients with LLST on ICU admission. METHODS: This prospective observational study included all patients admitted to 39 ICUs in a 45-day period in 2011. We recorded hospitals' characteristics (availability of intermediate care units, usual availability of ICU beds, and financial model) and patients' characteristics (demographics, reason for admission, functional status, risk of death, and LLST on ICU admission (withholding/withdrawing; specific techniques affected)). The primary outcome was 30-day survival for patients with LLST on ICU admission. Statistical analysis included multilevel logistic regression models. RESULTS: We recruited 3042 patients (age 62.5 ± 16.1 years). Most ICUs (94.8%) admitted patients with LLST, but only 238 (7.8% [95% CI 7.0-8.8]) patients had LLST on ICU admission; this group had higher ICU mortality (44.5 vs. 9.4% in patients without LLST; p < 0.001). Multilevel logistic regression showed a contextual effect of the hospital in LLST on ICU admission (median OR = 2.30 [95% CI 1.59-2.96]) and identified the following patient-related variables as independent factors associated with LLST on ICU admission: age, reason for admission, risk of death, and functional status. In patients with LLST on ICU admission, 30-day survival was 38% (95% CI 31.7-44.5). Factors associated with survival were age, reason for admission, risk of death, and number of reasons for LLST on ICU admission. CONCLUSIONS: The frequency of ICU admission with LLST is low but probably increasing; nearly one third of these patients survive for ≥ 30 days.

10.
FMC ; 27(1): 28-33, 2020 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-32288501
11.
Arq Bras Cardiol ; 80(1): 77-82, 71-6, 2003 Jan.
Artigo em Inglês, Português | MEDLINE | ID: mdl-12612726

RESUMO

OBJECTIVE: To assess the in-hospital evolution of patients undergoing percutaneous stent placement in the carotid arteries. METHODS: From August 1996 to April 2001, we studied 86 patients with carotid arterial obliterative lesions > 70% who were treated with percutaneous stent placement in the carotid arteries. We assessed the rate of success of the implantation and of the procedure, the types of stents used, mortality rate, and neurological complications. RESULTS: Successful implantation was obtained in 98.9% of the cases, and the procedure was successful in 91.8%. The Wallstent was the most frequently used stent (73 patients - 77%). Cerebral strokes occurred as follows: 3 (3.2%) transient ischemic attacks, 1 (1.1%) minor stroke, and 3 (3.1%) major strokes. One (1.1%) patient died during hospitalization. CONCLUSION: The high rate of success of stent implantation (98.9%) in addition to the low rate of cerebral stroke/death (4.2%) showed the efficiency and safety of percutaneous stent placement in carotid arteries.


Assuntos
Implante de Prótese Vascular/normas , Artéria Carótida Interna/cirurgia , Estenose das Carótidas/terapia , Stents , Idoso , Implante de Prótese Vascular/efeitos adversos , Brasil/epidemiologia , Estenose das Carótidas/mortalidade , Angiografia Cerebral , Feminino , Seguimentos , Humanos , Ataque Isquêmico Transitório/etiologia , Masculino , Pessoa de Meia-Idade , Stents/efeitos adversos , Acidente Vascular Cerebral/etiologia
12.
Arq Bras Cardiol ; 79(5): 466-75, 2002 Nov.
Artigo em Inglês, Português | MEDLINE | ID: mdl-12447497

RESUMO

OBJECTIVE: Analyze the dromotropic disturbances (vector-electrocardiographic), and the possible anatomic causes, provoked by selective alcohol injection in the septal branch, for percutaneous treatment, of obstructive hypertrophic cardiomyopathy. METHODS: Ten patients with a mean age of 52.7 years underwent percutaneous septal ablation (PTSA) from october 1998; all in functional class III/IV). Twelve-lead electrocardiogram was performed prior to and during PTSA, and later electrocardiogram and vectorcardiogram according to Frank's method. The patients were followed up for 32 months. RESULTS: On electrocardiogram (ECG) prior to PTSA all patients had sinus rhythm and left atrial enlargement, 8 left ventricular hypertrophy of systolic pattern. On ECG immediately after PTSA, 8 had complete right bundle-branch block; 1 transient total atrioventricular block; 1 alternating transient bundle-branch block either right or hemiblock. On late ECG 8 had complete right bundle-branch block confirmed by vectorcardiogram, type 1 or Grishman. CONCLUSION: Septal fibrosis following alcohol injection caused a predominance of complete right bundle-branch block, different from surgery of myotomy/myectomy.


Assuntos
Bloqueio de Ramo/induzido quimicamente , Cardiomiopatia Hipertrófica/cirurgia , Ablação por Cateter/métodos , Etanol/uso terapêutico , Septos Cardíacos/efeitos dos fármacos , Vetorcardiografia , Adulto , Idoso , Bloqueio de Ramo/fisiopatologia , Cardiomiopatia Hipertrófica/fisiopatologia , Feminino , Fibrose , Septos Cardíacos/patologia , Septos Cardíacos/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
15.
JACC Cardiovasc Interv ; 6(11): 1203-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24262620

RESUMO

OBJECTIVES: This study sought to randomly compare cerebral protection with ANGIOGUARD (Cordis Corporation, Bridgewater, New Jersey) with Mo.Ma (Invatec/Medtronic Vascular Inc, Santa Rosa, California) during carotid artery stenting (CAS), using diffusion-weighted magnetic resonance imaging (DW-MRI) to detect new ischemic cerebral lesions. The number, size, and location of lesions were analyzed. BACKGROUND: The choice of the type of cerebral protection during CAS is controversial. METHODS: From July 2008 to July 2011, 60 patients undergoing CAS were randomized to ANGIOGUARD or Mo.Ma, distributed by chance, 30 patients for each group. All patients underwent DW-MRI before and after CAS. An independent neuroradiologist blinded to the cerebral protection used analyzed the images. Univariate and multivariate logistic models were fitted to analyze new ischemic lesions. Alternatively, a propensity score approach was used to reduce the bias due to differences between the groups. For the number of lesions, we used Poisson regression models. RESULTS: New ischemic lesions seen on DW-MRI were present in 63.3% of the ANGIOGUARD group versus 66.7% of the Mo.Ma cohort (p = 0.787). The number of ischemic cerebral lesions per patient, when present, was significantly lower in the Mo.Ma group (a median of 6 lesions per patient vs. a median of 10 in the ANGIOGUARD, p < 0.001). Most lesions were small (<0.5 mm) and localized in the ipsilateral territory. One patient in the ANGIOGUARD group had a minor stroke during CAS (1.66%). CONCLUSIONS: New ischemic lesions seen on DW-MRI were present in both groups in >60%, but the number of lesions per patient was greater in the ANGIOGUARD group. No death or disabling stroke occurred during at least 1 year of follow-up in both cohorts.


Assuntos
Angioplastia/instrumentação , Isquemia Encefálica/prevenção & controle , Estenose das Carótidas/terapia , Circulação Cerebrovascular , Dispositivos de Proteção Embólica , Stents , Idoso , Angioplastia/efeitos adversos , Doenças Assintomáticas , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Brasil , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/fisiopatologia , Distribuição de Qui-Quadrado , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Pontuação de Propensão , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/prevenção & controle , Fatores de Tempo , Resultado do Tratamento
16.
Arq Bras Cardiol ; 91(4): 213-6, 234-7, 2008 Oct.
Artigo em Inglês, Português | MEDLINE | ID: mdl-19009172

RESUMO

BACKGROUND: Stroke is a feared complication after coronary artery bypass grafting surgery (CABG), with an incidence between 1.3 and 4.3%. OBJECTIVE: To identify predictive factors for stroke after CABG in the modern era of cardiac surgery. METHODS: This is a case-control study of 65 pairs of patients, paired by sex, age (+ 3 years) and date of CABG (+ 3 months). The cases were patients submitted to elective CABG with extracorporeal circulation (ECC) that presented stroke (defined as clinical neurological deficit up to 24 hours post-operatively and confirmed by imaging assessment) and the controls were those individuals submitted to elective CABG with ECC, but without stroke. RESULTS: The univariate analysis demonstrated that the number of revascularized vessels was associated with the occurrence of stroke after the CABG (3 +/- 0.8 vs. 2.76 +/- 0.8, p = 0.01). The multivariate analysis by conditional logistic regression showed that systemic arterial hypertension (SAH) [OR: 6.1 (1.5 - 24), p = 0.009] and diabetes mellitus (DM) [OR: 3.1 (1.09 - 11), p= 0.03] were the determinants of the highest chance of stroke after CABG, whereas acute myocardial infarction (AMI) > 1 month, was the determinant of the lowest chance of stroke [OR: 0.1 (0.03 - 0.36), p = 0.003]. CONCLUSION: Hypertension and diabetes mellitus were identified as independent predictors of stroke within the first 24 postoperative hours after CABG. In patients with such risk factors, it is possible that the knowledge of the causal mechanisms of brain injury represents a strategy capable of decreasing the incidence of stroke after CABG.


Assuntos
Ponte de Artéria Coronária , Acidente Vascular Cerebral/etiologia , Idoso , Estudos de Casos e Controles , Complicações do Diabetes , Feminino , Humanos , Hipertensão/complicações , Modelos Logísticos , Masculino , Período Pós-Operatório , Valor Preditivo dos Testes , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Fatores de Tempo
17.
Eur Biophys J ; 35(6): 495-501, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16572269

RESUMO

We have performed a very extensive investigation of chromatin folding in different buffers over a wide range of ionic conditions similar to those found in eukaryotic cells. Our results show that in the presence of physiological concentrations of monovalent cations and/or low concentrations of divalent cations, small chicken erythrocyte chromatin fragments and chromatin from HeLa cells observed by transmission electron microscopy (TEM) show a compact folding, forming circular bodies of approximately 35 nm in diameter that were found previously in our laboratory in studies performed under very limited conditions. Since TEM images are obtained with dehydrated samples, we have performed atomic force microscopy (AFM) experiments to analyze chromatin structure in the presence of solutions containing different cation concentrations. The highly compact circular structures (in which individual nucleosomes are not visible as separated units) produced by small chromatin fragments in interphase ionic conditions observed by AFM are equivalent to the structures observed by TEM with chromatin samples prepared under the same ionic conditions. We have also carried out experiments of sedimentation and trypsin digestion of chromatin fragments; the results obtained confirm our AFM observations. Our results suggest that the compaction of bulk interphase chromatin in solution at room temperature is considerably higher than that generally considered in current literature. The dense chromatin folding observed in this study is consistent with the requirement of compact chromatin structures as starting elements for the building of metaphase chromosomes, but poses a difficult physical problem for gene expression during interphase.


Assuntos
Cátions/química , Montagem e Desmontagem da Cromatina/fisiologia , Cromatina/química , Animais , Fenômenos Biofísicos , Biofísica , Galinhas , Cromatina/ultraestrutura , Eritrócitos , Células HeLa , Humanos , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Tripsina , Água
18.
Chromosome Res ; 13(7): 725-43, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16235122

RESUMO

We have performed a very extensive electron microscopy investigation of the chromatin structures extruded from partially denatured metaphase chromosomes from HeLa cells under a wide variety of conditions. Denatured chromosomes having fibres as the dominant structural element are obtained in the presence of buffers of very low concentration or after incubation with water. At slightly higher ionic concentrations, metaphase chromosomes become granulated. The most frequently observed granules have a diameter of about 35 nm and show the same structural characteristics as the compact cylindrical chromatin bodies previously found in our laboratory in studies performed using small chromatin fragments. Our results suggest that fibres are formed by the face-to-face association of 35-nm chromatin bodies. We have observed a very compact morphology of chromosomes in solutions containing intracellular concentrations of monovalent cations and the Mg2+ concentration found in metaphase. The most abundant structural elements observed in chromatin extruded from partially denatured compact metaphase chromosomes are multilayered plate-like structures. This is the first time that these planar structures have been reported. The observation of the irregular plates found in some preparations and of the small planar structures seen in aggregates of small chromatin fragments suggests that plates are formed by side-by-side association of compact chromatin bodies.


Assuntos
Cromatina/química , Cromatina/ultraestrutura , Cromossomos Humanos , Metáfase , Ácido Acético/farmacologia , Animais , Soluções Tampão , Núcleo Celular/efeitos dos fármacos , Galinhas , Cromatina/isolamento & purificação , Temperatura Baixa , Reagentes de Ligações Cruzadas/farmacologia , DNA de Neoplasias/metabolismo , Ácido Egtázico/farmacologia , Eletroforese em Gel de Ágar , Eritrócitos/citologia , Fixadores/farmacologia , Glutaral/farmacologia , Células HeLa , Humanos , Magnésio/farmacologia , Metanol/farmacologia , Modelos Biológicos , Peso Molecular , Conformação de Ácido Nucleico/efeitos dos fármacos , Nucleossomos/ultraestrutura , Concentração Osmolar , Fatores de Tempo
19.
Rapid Commun Mass Spectrom ; 17(4): 330-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12569443

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is consumed as the racemate but some metabolic steps are enantioselective. In addition, chiral properties are preserved during MDMA biotransformation. A quantitative analytical methodology using gas chromatography/mass spectrometry (GC/MS) to determine enantioselective disposition in the body of MDMA and its main metabolites including 3,4-methylenedioxyamphetamine (MDA), 4-hydroxy-3-methoxymethamphetamine (HMMA), and 4-hydroxy-3-methoxyamphetamine (HMA) was developed. Plasma and urine samples were collected from a male volunteer. The analysis of MDMA, MDA, and 4-hydroxy-3-methoxy metabolites by GC/MS required a two-step derivatization procedure. The first step consisted of derivatization of the amine with enantiomerically pure Mosher's reagent ((R)-MTPCl). Triethylamine was used as a base to neutralize hydrochloric acid formed during the reaction allowing quantitative derivatization, which resulted in a substantial improvement in the sensitivity of the method compared with other previously described techniques. Further treatment with ammonium hydroxide was required since both amine and hydroxyl groups underwent derivatization in the reaction. Ammonium hydroxide breaks bonds formed with hydroxyl groups without affecting amine derivatives. The second derivatization step using hexamethyldisilazane was needed for metabolites containing phenol residues. This derivatization method permitted the stereochemically specific study of MDMA and its main monohydroxylated metabolites by GC/MS. A detailed study of the chemical reactions involved in the derivatization steps was indispensable to develop a straightforward, sensitive, and reproducible method for the analysis of the parent drug compound and its metabolites.


Assuntos
3,4-Metilenodioxianfetamina/química , 3,4-Metilenodioxianfetamina/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metanfetamina/análogos & derivados , 3,4-Metilenodioxianfetamina/sangue , 3,4-Metilenodioxianfetamina/urina , Alucinógenos/sangue , Alucinógenos/química , Alucinógenos/metabolismo , Alucinógenos/urina , Humanos , Masculino , Metanfetamina/sangue , Metanfetamina/química , Metanfetamina/metabolismo , Metanfetamina/urina , Conformação Molecular , Valores de Referência , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/métodos
20.
Arq. bras. cardiol ; 91(4): 234-237, out. 2008. tab
Artigo em Inglês, Português | LILACS | ID: lil-496595

RESUMO

FUNDAMENTO: O acidente vascular encefálico (AVE) é uma temida complicação após cirurgia de revascularização do miocárdio (CRM), com incidência entre 1,3 por cento e 4,3 por cento. OBJETIVO: Identificar fatores preditores de AVE após CRM, na era moderna da cirurgia cardíaca. MÉTODOS: Este é um estudo caso-controle de 65 pares de pacientes, no qual o pareamento foi realizado por sexo, idade (+ 3 anos) e data da CRM (+ 3 meses). Os casos são pacientes submetidos à CRM eletiva com circulação extracorpórea (CEC), que apresentaram AVE (definido como déficit clínico neurológico até 24 horas de pós-operatório e confirmado por exame de imagem), e os controles aqueles submetidos à CRM eletiva com CEC sem AVE. RESULTADOS: A análise univariada revelou que o número de vasos revascularizados foi associado com a ocorrência de AVE após a CRM (3 ± 0,8 vs. 2,76 ± 0,8, p = 0,01). Na análise multivariada por regressão logística condicional, a hipertensão arterial sistêmica [OR: 6,1 (1,5 - 24), p = 0,009] e o diabete melito [OR: 3,1 (1,09 - 11), p= 0,03] foram determinantes de maior chance de AVE após CRM, e o infarto agudo do miocárdio > 1 mês determinante de menor chance [OR: 0,1 (0,03 - 0,36), p = 0,003]. CONCLUSÃO: Hipertensão e diabete melito foram identificados como preditores independentes de AVE nas primeiras 24 horas de pós-operatório de CRM. Em pacientes com tais fatores de risco, é possível que o conhecimento dos mecanismos causadores da injúria cerebral represente uma estratégia capaz de diminuir a incidência de AVE após CRM.


BACKGROUND: Stroke is a feared complication after coronary artery bypass grafting surgery (CABG), with an incidence between 1.3 and 4.3 percent. OBJECTIVE: To identify predictive factors for stroke after CABG in the modern era of cardiac surgery. METHODS: This is a case-control study of 65 pairs of patients, paired by sex, age (+ 3 years) and date of CABG (+ 3 months). The cases were patients submitted to elective CABG with extracorporeal circulation (ECC) that presented stroke (defined as clinical neurological deficit up to 24 hours post-operatively and confirmed by imaging assessment) and the controls were those individuals submitted to elective CABG with ECC, but without stroke. RESULTS: The univariate analysis demonstrated that the number of revascularized vessels was associated with the occurrence of stroke after the CABG (3 ± 0.8 vs. 2.76 ± 0.8, p = 0.01). The multivariate analysis by conditional logistic regression showed that systemic arterial hypertension (SAH) [OR: 6.1 (1.5 - 24), p = 0.009] and diabete mellitus (DM) [OR: 3.1 (1.09 - 11), p= 0.03] were the determinants of the highest chance of stroke after CABG, whereas acute myocardial infarction (AMI) > 1 month, was the determinant of the lowest chance of stroke [OR: 0.1 (0.03 - 0.36), p = 0.003]. CONCLUSION: Hypertension and diabete mellitus were identified as independent predictors of stroke within the first 24 postoperative hours after CABG. In patients with such risk factors, it is possible that the knowledge of the causal mechanisms of brain injury represents a strategy capable of decreasing the incidence of stroke after CABG.


Assuntos
Idoso , Feminino , Humanos , Masculino , Ponte de Artéria Coronária , Acidente Vascular Cerebral/etiologia , Estudos de Casos e Controles , Complicações do Diabetes , Hipertensão/complicações , Modelos Logísticos , Período Pós-Operatório , Valor Preditivo dos Testes , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Fatores de Tempo
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