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1.
Eur Radiol ; 31(3): 1608-1619, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32827266

RESUMO

OBJECTIVES: To analyse the predictive value of the volume of enhancement of disease (VED), based on the CT arterial enhancement coefficient (ΔArt%), in the evaluation of the sorafenib response in patients with advanced hepatocellular carcinoma (HCC). METHODS: Patients with sorafenib-treated advanced HCC, who underwent a multiphase contrast-enhanced CT before (T0) and after 60-70 days of starting therapy (T1), were included. The same target lesions utilised for the response evaluation according to modified Response Evaluation Criteria in Solid Tumors criteria were retrospectively used for the ΔArt% calculation ([(HUarterial phase - HUunenhanced phase) / HUunenhanced phase] × 100). ΔArt% was weighted for the lesion volume to obtain the VED. We compared VEDT0 and VEDT1 values in patients with clinical benefit (CB) or progressive disease (PD). The impact of VED, ancillary imaging findings, and blood chemistries on survival probability was evaluated. RESULTS: Thirty-two patients (25 men, mean age 65.8 years) analysed between 2012 and 2016 were selected. At T1, 8 patients had CB and 24 had PD. VEDT0 was > 70% in 8/8 CB patients compared with 12/24 PD patients (p = 0.011). Patients with VEDT0 > 70% showed a significantly higher median survival than those with lower VEDT0 (451.5 days vs. 209.5 days, p = 0.032). Patients with VEDT0 > 70% and alpha-fetoproteinT0 ≤ 400 ng/ml had significantly longer survival than all other three combinations. In multivariate analysis, VEDT0 > 70% emerged as the only factor independently associated with survival (p = 0.037). CONCLUSION: In patients with advanced HCC treated with sorafenib, VED is a novel radiologic parameter obtained by contrast-enhanced CT, which could be helpful in selecting patients who are more likely to respond to sorafenib, and with a longer survival. KEY POINTS: • To achieve the best results of treatment with sorafenib in advanced HCC, a strict selection of patients is needed. • New radiologic parameters predictive of the response to sorafenib would be essential. • Volume of enhancement of disease (VED) is a novel radiologic parameter obtained by contrast-enhanced CT, which could be helpful in selecting patients who are more likely to respond to therapy, and with a longer survival.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Estudos Retrospectivos , Sorafenibe/uso terapêutico , Tomografia Computadorizada por Raios X , Resultado do Tratamento
2.
Mol Pharm ; 14(6): 1980-1987, 2017 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-28441873

RESUMO

The family of concentrative Na+/nucleoside cotransporters in humans is constituted by three subtypes, namely, hCNT1, hCNT2, and hCNT3. Besides their different nucleoside selectivity, hCNT1 and hCNT2 have a Na+/nucleoside stoichiometry of 1:1, while for hCNT3 it is 2:1. This distinct stoichiometry of subtype 3 might hint the existence of a secondary sodium-binding site that is not present in the other two subtypes, but to date their three-dimensional structures remain unknown and the residues implicated in Na+ binding are unclear. In this work, we have identified and characterized the Na+ binding sites of hCNT3 by combining molecular modeling and mutagenesis studies. A model of the transporter was obtained by homology modeling, and key residues of two sodium-binding sites were identified and verified with a mutagenesis strategy. The structural model explains the altered sodium-binding properties of the hCNT3C602R polymorphic variant and supports previously generated data identifying the determinant residues of nucleoside selectivity, paving the way to understand how drugs can target this plasma membrane transporter.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Sítios de Ligação/genética , Sítios de Ligação/fisiologia , Western Blotting , Células HEK293 , Humanos , Proteínas de Membrana Transportadoras/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína
4.
Pharmacogenomics J ; 15(6): 473-87, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26526073

RESUMO

The SCL22A1 gene encodes the broad selectivity transporter hOCT1. hOCT1 is expressed in most epithelial barriers thereby contributing to drug pharmacokinetics. It is also expressed in different drug target cells, including immune system cells and others. Thus, this membrane protein might also contribute to drug pharmacodynamics. Up to 1000 hOCT1 polymorphisms have been identified so far, although only a small fraction of those have been mechanistically studied. A paradigm in the field of drug transporter pharmacogenetics is the impact of hOCT1 gene variability on metformin clinical parameters, affecting area under the concentration-time curve, Cmax and responsiveness. However, hOCT1 also mediates the translocation of a variety of drugs used as anticancer, antiviral, anti-inflammatory, antiemetic agents as well as drugs used in the treatment of neurological diseases among. This review focuses exclusively on those drugs for which some pharmacogenetic data are available, and aims at highlighting the need for further clinical research in this area.


Assuntos
Interações Medicamentosas/genética , Transportador 1 de Cátions Orgânicos/genética , Preparações Farmacêuticas/metabolismo , Polimorfismo Genético/genética , Animais , Humanos , Farmacogenética/métodos
5.
Pharmacogenomics J ; 15(4): 363-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25582574

RESUMO

Bendamustine is used in the treatment of chronic lymphocytic leukemia (CLL). Routes for bendamustine entry into target cells are unknown. This study aimed at identifying transporter proteins implicated in bendamustine uptake. Our results showed that hOCT1 is a bendamustine transporter, as bendamustine could cis-inhibit the uptake of a canonical hOCT1 substrate, with a Ki in the micromolar range, consistent with the EC50 values of the cytotoxicity triggered by this drug in HEK293 cells expressing hOCT1. hOCT1 polymorphic variants determining impaired bendamustine-transporter interaction, consistently reduced bendamustine cytotoxicity in HEK293 cells stably expressing them. Exome genotyping of the SLC22A1 gene, encoding hOCT1, was undertaken in a cohort of 241 CLL patients. Ex vivo cytotoxicity to bendamustine was measured in a subset of cases and shown to correlate with SLC22A1 polymorphic variants. In conclusion, hOCT1 is a suitable bendamustine transporter, thereby contributing to its cytotoxic effect depending upon the hOCT1 genetic variants expressed.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Cloridrato de Bendamustina/metabolismo , Cloridrato de Bendamustina/farmacologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Transportador 1 de Cátions Orgânicos/genética , Transportador 1 de Cátions Orgânicos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacocinética , Cloridrato de Bendamustina/farmacocinética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Estudos de Coortes , DNA Complementar/genética , Transportador Equilibrativo 1 de Nucleosídeo/genética , Exoma/genética , Feminino , Genótipo , Células HEK293 , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-Idade , Transportadores de Ânions Orgânicos , Proteínas de Transporte de Cátions Orgânicos , Polimorfismo Genético/genética
6.
Radiol Med ; 117(2): 242-53, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22020423

RESUMO

PURPOSE: This study was done to evaluate whether and which of the magnetic resonance diffusion-weighted imaging (MR-DWI) parameters - apparent diffusion coefficient (ADC), diffusion (D) or perfusion fraction (f) - correlates with the degree of chronic liver disease progression. MATERIALS AND METHODS: Twenty-eight patients were evaluated with abdominal MR-DWI from March to November 2010: seven healthy volunteers, seven patients with chronic liver disease F0-F2 (METAVIR score), seven F3-F4 Child-Pugh A, and seven F4 Child-Pugh BC, classified as groups 1-4, respectively. DWI acquisitions were performed during breath-holding (b = 0-150 s/mm(2) and 1,000) and free breathing (multi-b = 0-200-400-600-800-1,000 s/mm(2)). Using a double-blind control procedure, two observers estimated ADC, D, and f by applying a region of interest (ROI) in 4/12 sections in the middle-lower portion of the right hepatic lobe. Statistical analysis was done with analysis of variance (ANOVA). RESULTS: A reduction in the mean value of f, ADC(150) and, to a lesser extent, ADC(1,000) is shown to progress from healthy volunteers (group 1) to cirrhosis patients (group 4), with wide overlap among groups. There were no statistically significant changes of D. CONCLUSIONS: Our results indicate that stratifying patients with chronic liver disease for clinical purposes cannot be done with DWI. However, there is a tendency among groups for reduced perfusion-related parameters as chronic liver disease progresses.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Hepatopatias/patologia , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Doença Crônica , Progressão da Doença , Feminino , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas
7.
J Microbiol Biol Educ ; 23(2)2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36061311

RESUMO

[This corrects the article DOI: 10.1128/jmbe.00151-21.].

8.
Braz J Biol ; 84: e256916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043839

RESUMO

Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Assuntos
Artrópodes , Crotalaria , Fabaceae , Alcaloides de Pirrolizidina , Animais , Monocrotalina/toxicidade
9.
Artigo em Inglês | MEDLINE | ID: mdl-34745409

RESUMO

Authors in the Journal of Microbiology and Biology Education (JMBE) have demonstrated a clear commitment to diversity, equity, and inclusion (DEI) through commentaries, instructional approaches, and research. However, analysis of JMBE literature using Kendi's antiracist framework (How To Be an Antiracist, 2019) offers additional opportunities for growth. These opportunities are discussed and framed under five emergent conceptual categories (ECCs). First, capitalistic goals (e.g., productivity) are often drivers for DEI initiatives but disproportionately benefit those with power. Humanity-centered reasons, like honoring community values, are also important motivations. Second, faculty are often targeted as primary agents of change for DEI, but more powerful stakeholders such as department and institutional leadership can also implement equitable policies and practices to widen the impact of DEI initiatives. Third, study scopes are sometimes focused on the outcomes of inequity (e.g., lower retention rates for students of color) rather than the systemic causes (e.g., exclusivity of science). While outcomes are important to research, studies should create clear connections and distinctions between the systems and symptoms of inequity. Fourth, active learning and authentic research experiences are not automatically inclusive and do not necessarily validate students' identities. Such approaches may be more impactful when tailored for context and student background. Finally, language and communication can have broad impacts on DEI efforts. As a community, we may need to be more critical of our shared language and communication. This review discusses the five ECCs in depth and offers next steps for supporting DEI across the biology and microbiology education community.

10.
Braz. j. biol ; 84: e256916, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355874

RESUMO

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Resumo Crotalaria (Linnaeus, 1753) (Fabaceae) ocorre abundantemente em regiões tropicais e subtropicais e tem cerca de 600 espécies conhecidas. Estas plantas são amplamente utilizadas na agricultura, principalmente como cobertura e adubos verdes, além da sua utilização no manejo de fitonematoides. Uma característica marcante destas espécies é a produção de alcalóides pirrolizidinicos (APs), aleloquímicos secundários envolvidos na defesa das plantas contra os herbívoros. Nas espécies de Crotalaria, a monocrotalina é a AP predominante, que tem muitas atividades biológicas relatadas, incluindo citotoxicidade, tumorigenicidade, hepatotoxicidade e neurotoxicidade, além de uma vasta gama de interações ecológicas. Assim, estudos têm procurado elucidar os efeitos desse composto para promover um incremento na flora e fauna (principalmente insetos e nematoides) associados aos agroecossistemas, favorecendo o controle biológico natural. Esta revisão compila informações sobre a monocrotalina, mostrando tais efeitos nesses ambientes, tanto acima como abaixo do solo e a sua potencial utilização em programas de manejo de pragas.


Assuntos
Animais , Artrópodes , Alcaloides de Pirrolizidina , Crotalaria , Fabaceae , Monocrotalina/toxicidade
11.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469325

RESUMO

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Resumo Crotalaria (Linnaeus, 1753) (Fabaceae) ocorre abundantemente em regiões tropicais e subtropicais e tem cerca de 600 espécies conhecidas. Estas plantas são amplamente utilizadas na agricultura, principalmente como cobertura e adubos verdes, além da sua utilização no manejo de fitonematoides. Uma característica marcante destas espécies é a produção de alcalóides pirrolizidinicos (APs), aleloquímicos secundários envolvidos na defesa das plantas contra os herbívoros. Nas espécies de Crotalaria, a monocrotalina é a AP predominante, que tem muitas atividades biológicas relatadas, incluindo citotoxicidade, tumorigenicidade, hepatotoxicidade e neurotoxicidade, além de uma vasta gama de interações ecológicas. Assim, estudos têm procurado elucidar os efeitos desse composto para promover um incremento na flora e fauna (principalmente insetos e nematoides) associados aos agroecossistemas, favorecendo o controle biológico natural. Esta revisão compila informações sobre a monocrotalina, mostrando tais efeitos nesses ambientes, tanto acima como abaixo do solo e a sua potencial utilização em programas de manejo de pragas.

12.
Rev Sci Instrum ; 87(8): 084504, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27587140

RESUMO

This work presents an experimental design for studying low-velocity collisions into granular surfaces in low-gravity. In the experiment apparatus, reduced-gravity is simulated by releasing a free-falling projectile into a surface container with a downward acceleration less than that of Earth's gravity. The acceleration of the surface is controlled through the use of an Atwood machine, or a system of pulleys and counterweights. The starting height of the surface container and the initial separation distance between the projectile and surface are variable and chosen to accommodate collision velocities up to 20 cm/s and effective accelerations of ∼0.1 to 1.0 m/s(2). Accelerometers, placed on the surface container and inside the projectile, provide acceleration data, while high-speed cameras capture the collision and act as secondary data sources. The experiment is built into an existing 5.5 m drop tower frame and requires the custom design of all components, including the projectile, surface sample container, release mechanism, and deceleration system. Data from calibration tests verify the efficiency of the experiment's deceleration system and provide a quantitative understanding of the performance of the Atwood system.

13.
Rhinology ; 43(4): 251-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16405267

RESUMO

Specific ultrastructural findings have widely been described in case of obstructive nasal diseases due to congenital defects. Ciliary impairment has in particular been observed as the main pathological feature in these conditions. In this study, nasal mucosal samples from different pathologies have been collected via the "brushing" technique and analysed by transmission electron microscopy. TEM analysis was focused on specific features, such as the numerical array of peripheral and central doublets of the cilium axoneme, including eventual microtubular disarrangement; partial or total loss of inner and/or outer dynein arms; defects of radial spokes and nexin links; disorientation of the ciliary axis in closely adjacent cilia, calculating the angle between the line crossing the central microtubular core and the horizontal ciliary axis and compound cilia (CC). Statistical comparison was carried out between study and control groups. A significant incidence of organic ciliary defects was found not only in patients with inflammatory processes, but mostly in those supposed to have a long-lasting nasal respiratory disease due to mechanical stenosis in relation to septum deviation and turbinate hypertrophy. Prevalence and percentage of compound cilia were instead more related to inflammatory conditions. The "brushing" technique can be considered an easy and reliable method for the assessment of the condition of the nasal mucosa. According to the findings derived from this study, mechanical nasal obstruction seems to cause major alterations on the nasal ciliary arrangement, thus determining a functional impairment on the whole nasal function.


Assuntos
Cílios/ultraestrutura , Transtornos da Motilidade Ciliar/patologia , Obstrução Nasal/patologia , Adulto , Análise de Variância , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Ann Thorac Surg ; 71(5): 1670-2, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11383819

RESUMO

We report a patient who presented with paraprosthetic leak complicated by dissection of the interatrial septum after mitral valve replacement. A review of the literature provides confirmation that only 3 cases have been previously reported of this potential, albeit extremely rare, complication of prosthetic mitral valve replacement. Prosthesis oversizing and improper mitral annular handling appeared to be the predisposing factors of this complication.


Assuntos
Átrios do Coração/diagnóstico por imagem , Septos Cardíacos/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Deiscência da Ferida Operatória/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Ecocardiografia Transesofagiana , Átrios do Coração/cirurgia , Septos Cardíacos/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Complicações Pós-Operatórias/cirurgia , Recidiva , Reoperação , Ruptura Espontânea , Deiscência da Ferida Operatória/cirurgia , Técnicas de Sutura
15.
Ann Thorac Surg ; 69(1): 47-50, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10654484

RESUMO

BACKGROUND: Aortic valve replacement in elderly patients with a small aortic annulus may pose difficult problems in terms of prosthesis selection. We have evaluated the hemodynamic performance of the 21-mm Carpentier-Edwards Perimount bioprosthesis implanted in elderly patients. METHODS: From July 1996 to June 1998, 19 patients (17 women and 2 men, mean age 76+/-4 years and mean body surface area 1.73+/-0.13 m2), had aortic valve replacement with a 21-mm Carpentier-Edwards Perimount bioprosthesis. The hemodynamic performance of the valve was evaluated in 16 patients, who completed at least a 6-month follow-up interval, with transthoracic color-Doppler echocardiography with particular reference to peak and mean transprosthetic gradients, effective orifice area index, and regression of left ventricular mass index. RESULTS: There were no late deaths and no major postoperative complications. At a mean follow-up of 12+/-7 months, compared to discharge, all patients showed clinical improvement with a significant reduction of peak gradient (from 23+/-4 to 21+/-6 mm Hg, p = 0.04) and left ventricular mass index (from 181+/-23 to 153+/-20 g/m2; p<0.001), whereas mean gradient (from 13+/-3 to 13+/-4 mm Hg, p = not significant) and effective orifice area index (from 1.12+/-0.34 to 1.13+/-0.28 cm2/m2, p = not significant) remained substantially unchanged. CONCLUSIONS: The use of a 21-mm Carpentier-Edwards Perimount bioprosthesis is associated with low transprosthetic gradients and significant reduction in left ventricular hypertrophy after aortic valve replacement. The results of our study suggest that a 21-m Carpentier-Edwards Perimount bioprosthesis should be considered a valid option in elderly patients with aortic valve disease and a small aortic annulus.


Assuntos
Valva Aórtica , Bioprótese , Próteses Valvulares Cardíacas , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Superfície Corporal , Débito Cardíaco/fisiologia , Ecocardiografia Doppler em Cores , Feminino , Seguimentos , Implante de Prótese de Valva Cardíaca , Ventrículos do Coração/diagnóstico por imagem , Hemodinâmica , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Masculino , Complicações Pós-Operatórias , Desenho de Prótese , Propriedades de Superfície , Taxa de Sobrevida , Resultado do Tratamento
16.
Ann Thorac Surg ; 68(6): 2147-51, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10616992

RESUMO

BACKGROUND: The Edwards Prima stentless valve (EPSV) is a porcine aortic root cylinder with resected coronary ostia, fixed in glutaraldehyde at low pressure. The purpose of this study was to evaluate the hemodynamic performance of the EPSV 1 year after aortic valve replacement. METHODS: From December 1994 to February 1996, 29 patients underwent aortic valve replacement with EPSV used in the subcoronary position (group 1, n = 23) or as a root replacement (group 2, n = 6). Hemodynamic performance of EPSV was assessed by two-dimensional Doppler echocardiography at 1 week, 6 months, and 1 year by calculating peak transprosthetic velocity, peak and mean gradients, effective orifice area, degree of aortic regurgitation, and regression of left ventricular hypertrophy. RESULTS: There were no operative deaths. One patient in group 2 died after 3 months at reoperation for endocarditis. In group 1 early mean gradient (25+/-5 mm Hg for 23 mm and 19+/-5 mm Hg for 25 mm) decreased at 6 months and 1 year in the 23-mm size (17+/-7 mm Hg and 15+/-4 mm Hg, p < 0.01) and at 1 year in the 25-mm size (14+/-4 mm Hg, p = 0.03) without modifications of the effective orifice area in both sizes. A significant reduction in left ventricular hypertrophy occurred at 6 months and 1 year in both sizes. In group 2 lower early gradients were recorded with subsequent improvement at follow-up; reduction in left ventricular hypertrophy occurred as well. CONCLUSIONS: The EPSV used in the subcoronary position has shown high early gradients, which partially regressed at 6 months, with further improvement at 1 year. Gradients are attributed to inward folding of the Dacron cloth at the right coronary ostium, being more evident in patients with aortic stenosis without dilatation of the aortic root and coronary ostia close to the annulus. In such patients a better early hemodynamic result can be obtained by using the EPSV as a root replacement.


Assuntos
Valva Aórtica/cirurgia , Bioprótese , Implante de Prótese de Valva Cardíaca , Hemodinâmica , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia Doppler , Feminino , Seguimentos , Humanos , Masculino , Desenho de Prótese
17.
Ann Thorac Surg ; 72(1): 33-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11465226

RESUMO

BACKGROUND: This study compares the hemodynamic performance of stented and stentless bioprostheses used for aortic valve replacement in patients with aortic stenosis and small aortic root. METHODS: Between 1995 and 1998, 37 patients with a 21-mm aortic annulus (group 1) underwent aortic valve replacement with either a 21-mm Edwards Perimount or a 23-mm St. Jude Toronto bioprosthesis whereas 47 patients with a 23-mm aortic annulus (group 2) received either a 23-mm Medtronic Mosaic or a 25-mm Edwards Prima bioprosthesis. In each group mean and peak gradients, effective orifice area index, and left ventricular mass index were compared during follow-up. RESULTS: Group 1 patients showed a significant reduction of mean (p < 0.001) and peak gradients (p = 0.001) during follow-up, more evident for St. Jude Toronto versus Edwards Perimount (p = 0.02 and p = 0.05, respectively). Group 2 patients showed a significant reduction of mean and peak gradients (p < 0.001), more evident for Edwards Prima versus Medtronic Mosaic (p < 0.001 and p = 0.07, respectively). Effective orifice area index significantly increased only in group 1 (p = 0.005). Left ventricular mass index significantly decreased in all patients regardless of the type of valve (p < 0.001). Patients with Edwards Prima showed a trend to a higher regression of left ventricular mass index versus Medtronic Mosaic recipients (p = 0.07). CONCLUSIONS: After aortic valve replacement, stented and stentless bioprostheses exhibited similar results with a more evident hemodynamic improvement during follow-up in the stentless valves. Stented bioprostheses of new generation, however, may parallel the hemodynamic performance of stentless valves and appear to be a valid alternative for aortic valve replacement in elderly patients with a small aortic annulus.


Assuntos
Estenose da Valva Aórtica/cirurgia , Bioprótese , Próteses Valvulares Cardíacas , Hemodinâmica/fisiologia , Complicações Pós-Operatórias/fisiopatologia , Stents , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Humanos , Masculino , Desenho de Prótese , Estudos Retrospectivos
18.
J Hum Hypertens ; 17(4): 253-63, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12692570

RESUMO

The study was carried out in two different models of left ventricular hypertrophy: athlete's heart and essential arterial hypertension. Three groups of strictly age-matched males were studied: one group of 10 young adult untreated essential hypertensive patients (H), a second group of 10 athletes (A), and a group of 10 healthy individuals as controls (C). A Sonos 5500 echograph with S4 harmonic transducer was used with Levovist (ultrasonic tracer) before and after dipyridamole injection; digitised images of quantitative myocardial contrast echocardiography were collected with Power Harmonic Doppler. Angio images were analysed using dedicated PC software by placing a region-of-interest on the septum. Peak intensity, half-time (HT), the area under the curve of appearance and disappearance of microbubbles at 2/3 of PI, both in absolute and indexed values (/LVMi), were sampled. The per cent increase of PI after dipyridamole was significantly higher in C (+73%, P < 0.01) than in H (+31%) and in A (+33%) (P < 0.05). The area of appearance was significantly lower in H in comparison with C and A, both at rest and after vasodilatation. The disappearance area after dipyridamole was significantly higher in C and in A (+124%) than in H (+104%) (P < 0.05). Some hypothesis could be made: an impairment in the coronary microcirculatory function in hypertensive patients could be because of an in-crease in the arteriolar resistance. Angiogenesis and several different functional adaptations are the mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.


Assuntos
Circulação Coronária/fisiologia , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Esportes , Adulto , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Diástole/fisiologia , Dipiridamol/uso terapêutico , Ecocardiografia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Hipertensão/tratamento farmacológico , Masculino , Microcirculação/fisiologia , Volume Sistólico/fisiologia , Fatores de Tempo , Resultado do Tratamento , Vasodilatação/fisiologia , Vasodilatadores/uso terapêutico , Função Ventricular Esquerda/fisiologia
19.
Biomed Pharmacother ; 46(1): 21-4, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1358242

RESUMO

Ten Caucasian males with HIV-related Kaposi's sarcoma, a disseminated disease which is refractory to usual therapies, underwent a single session of systemic hyperthermia with maintenance of core temperatures at 42 degrees C for 1 h. One complete remission and 7 partial remissions were identified when assessed 30 days post-treatment. Two mixed responses were noted in patients whose tumors showed autocrine growth. At 60 days 2 of the 7 partial responders began to show tumor progression. The complete remission persisted at 120 days. Surrogate markers of HIV activity fell in all responding patients. In no patient was there evidence of HIV activation. No adverse effects of heating were noted on CMV retinitis. Hairy leukoplakia resolved with heating in all patients. CD4 counts showed no appreciable change in any of the 8 patients with a presenting CD4 count below 60. In the 2 patients who presented with a CD4 count above 400, CD4 counts rose dramatically following treatment. No deaths were noted in this phase I study. The use of systemic hyperthermia in treatment of HIV-related illness warrants further study.


Assuntos
Complexo Relacionado com a AIDS/complicações , Hipertermia Induzida , Sarcoma de Kaposi/complicações , Sarcoma de Kaposi/terapia , Complexo Relacionado com a AIDS/imunologia , Adulto , Contagem de Células Sanguíneas , Linfócitos T CD4-Positivos/patologia , Humanos , Masculino , Sarcoma de Kaposi/imunologia
20.
J Heart Valve Dis ; 7(3): 299-304, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9651843

RESUMO

BACKGROUND AND AIMS OF THE STUDY: Aortic valve replacement in patients with a small aortic annulus may represent a surgical challenge. We have evaluated a simplified technique to enlarge the aortic annulus which consists of extending the aortotomy incision to divide the commissure between the left and non-coronary cusps into the interleaflet triangle without opening the left atrium. METHODS: This technique was used in 16 patients (15 women, one man; mean age 66 +/- 9 years) who underwent aortic valve replacement between August 1994 and February 1996. Aortic stenosis was the predominant valvular lesion. A mechanical prosthesis was implanted in 13 patients (81%) (21 mm in six, 23 mm in seven) while three received a bioprosthesis (21 mm in one, 23 mm in two). In all patients it was possible to insert a prosthesis at least one size larger than the original aortic annulus diameter. RESULTS: There were no operative deaths and no late deaths. Mean follow up was 20 +/- 6 months (range: 12 to 30 months). Echocardiographic controls at 12 months postoperatively showed no evidence of periprosthetic leaks or mitral regurgitation. Comparison with preoperative data showed no significant variations of mean aortic diameter at the sinus level (30.7 +/- 2.2 mm versus 31.3 +/- 2.6 mm) or at the sinotubular junction (33.6 +/- 2.7 mm versus 34.3 +/- 2.9 mm) (p = NS). Significant reduction of left ventricular mass was observed (314 +/- 57 g versus 260 +/- 45 g; p < 0.001). CONCLUSIONS: This technique is simple, reproducible and effective in allowing adequate enlargement of the aortic annulus and provides excellent clinical and hemodynamic results. Glutaraldehyde-fixed bovine pericardium used as a patch material showed no tendency to aneurysmal dilatation with progression of time at a maximum follow up of 30 months.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Pericárdio/transplante , Idoso , Animais , Bioprótese , Bovinos , Feminino , Seguimentos , Glutaral , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Desenho de Prótese , Reprodutibilidade dos Testes , Fatores de Tempo
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