Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Osteoporos Int ; 32(7): 1351-1358, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33479846

RESUMEN

Although lactation is associated with transient bone loss and body weight changes, the unchanged TBS could highlight a limited effectiveness in detecting dynamic bone properties in the first year postpartum. PURPOSE: To evaluate trabecular bone score (TBS) and bone mineral density (BMD) in postpartum women. METHODS: This was a 12-month prospective cohort study with 40 lactating postpartum women and 44 non-pregnant women. The inclusion criteria were as follows: aged between 18 and 35 years old, an uncomplicated term (≥37 weeks) pregnancy with a single fetus, and no intention of becoming pregnant within 12 months. BMD measurements, including spine, hip, forearm and whole body, were performed by DXA at four different time points after delivery: (1) 1st month, (2) 3rd-4th month, (3) 6th-9th month, and (4) ≥ 12th month postpartum. RESULTS: BMD measurements showed a statistically significant decrease at spine (1.134 vs. 1.088 g/cm2, p < 0.01), femoral neck (0.988 vs. 0.946 g/cm2, p < 0.01), total femur (0.971 vs. 0.933 g/cm2, p < 0.01), and whole body (1.132 vs. 1.119 g/cm2, p = 0.03) at the 2nd assessment (peak of lactation). There was early spinal recovery after the 3rd assessment with complete recovery in all skeletal sites. Although it has had significant weight loss (67.3 vs. 63.2 kg, p < 0.01) and body mass index reduction (25.2 vs. 23.4, p < 0.01), there was significant increment of spine BMD (1.134 vs. 1.165 g/cm2, p < 0.01) after 12-month follow-up. The TBS did not change over time. CONCLUSIONS: Although lactation is associated with transient bone loss and body weight changes, the unchanged TBS could highlight a limited effectiveness in detecting dynamic bone properties in the first year postpartum.


Asunto(s)
Densidad Ósea , Hueso Esponjoso , Absorciometría de Fotón , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Lactancia , Vértebras Lumbares/diagnóstico por imagen , Embarazo , Estudios Prospectivos
2.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 732-740, May-June 2019. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1011300

RESUMEN

Avaliou-se a influência da somatotropina recombinante bovina (rbST) sobre os metabolismos energético e mineral de búfalas entre 63e 154 dias em lactação. Foram utilizadas 22 búfalas, distribuídas em dois grupos experimentais: grupo rbST - aplicação de 500mg de rbST a cada 14 dias; grupo Controle - sem aplicação de rbST. A cada sete dias, foram coletadas amostras de sangue para a determinação do perfil bioquímico e mensuraram-se a produção de leite e o escore de condição corporal dos animais. As médias dos parâmetros estudados para os grupos rbST e Controle foram, respectivamente: produção de leite (PL): 6,44kg vs. 6,68kg; escore de condição corporal-ECC (1-5): 3,51 vs. 3,57; glicose: 70,58 vs. 64,81mg/dL (P = 0,0003); colesterol: 132,38 vs. 133,40mg/dL; triglicérides: 29,18 vs. 28,32mg/dL; proteína total: 8,57 vs. 8,75g/dL; albumina: 3,47 vs. 3,60g/dL; ureia: 32,46 vs. 33,86mg/dL; creatinina: 1,27 vs. 1,39mg/dL; cálcio:10,25 vs. 10,73mg/dL; fósforo:5,76 vs. 5,62mg/dL; e magnésio:3,70 vs. 3,70mg/dL. O uso de 500mg de rbSTinfluenciou o metabolismo da glicose, porém não modificou a PL, o ECC e os níveis dos demais parâmetros metabólicos estudados.(AU)


The aim was to evaluate the influence of recombinant bovine somatotropin (rbST) on the energy and mineral metabolism of buffaloes between 63 - 154 days in milk. Twenty-two buffaloes distributed in two experimental groups were used: Group rbST (n= 11) - application of 500mg of rbST every 14 days; Control Group (n= 11) - no rbST. Every seven days, blood samples were taken to determine the biochemical profile, and milk production and body condition score were measured. The averages of the variables for rbST and Control groups were, respectively: milk yield (MY) - 6.44kg vs. 6.68kg; body condition score (BCS) - 3.51 vs 3.57 (1-5); glucose - 70.58 vs. 64.81mg/dL (P = 0.0003); cholesterol - 132.38 vs. 133.40mg/dL; triglycerides -29.18 vs. 28.32mg/dL; total protein - 8.57 vs. 8.75g/dL; albumin - 3.47 vs 3.60g/dL; urea - 32.46 vs 33.86mg/dL; creatinine - 1.27 vs 1.39mg/dL; calcium - 10.25 vs. 10.73mg/dL; phosphorus - 5.76 vs 5.62mg/dL; and magnesium - 3.70 vs 3.70mg/dL. Use of 500mg rbST influenced glucose metabolism, but did not modify the MY, BCS and the levels of the other metabolic parameters studied.(AU)


Asunto(s)
Animales , Femenino , Embarazo , Proteínas Recombinantes/metabolismo , Búfalos/metabolismo , Hormona del Crecimiento/metabolismo , Leche , Alimentación Animal
3.
J Phys Condens Matter ; 31(22): 225802, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-30808010

RESUMEN

Topological objects interacting with lattice defects is an important topic in condensed matter physics. In this paper, we would like to explore the ballistic trajectory of an antiferromagnetic skyrmion in a racetrack to study processes such as collisions of skyrmions and holes in the magnetic sample. The skyrmion is impelled against the hole-obstacle by means of a spin polarized current. Depending on the skyrmion velocity (associated to the strength of the applied current) and the type of collision (frontal or lateral), it will be captured, scattered or completely destroyed by the hole. In some cases, this obstacle can shift the skyrmion center from a straight line to another one, and it appears as an effective way of manipulating skyrmion trajectories and dynamics.

4.
Sci Rep ; 7(1): 13982, 2017 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-29070908

RESUMEN

In this work, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by a and b respectively). Arrays with three different aspect ratios γ = a/b = [Formula: see text], [Formula: see text] and [Formula: see text] are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough γ. Our results also insinuate that the string tension connecting two magnetic monopoles in a pair vanishes in rectangular lattices with a critical ratio γ = γ c = [Formula: see text], supporting previous theoretical predictions.

5.
J Phys Condens Matter ; 28(45): 456002, 2016 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-27618358

RESUMEN

In this work, we report experimental and theoretical investigations performed in anti-spin ice structures, composed by square lattice of elongated antidots, patterned in nickel thin film. The magnetic vortex crystal state was obtained by micromagnetic simulation as the ground state magnetization, which arises due to the magnetic stray field at the antidot edges inducing chirality in the magnetization of platters among antidots. Ferromagnetic resonance (FMR) and magnetoresistance (MR) measurements were utilized to investigate the vortex crystal magnetization dynamics and magnetoelectric response. By using FMR, it was possible to detect the spin wave modes and vortex crystal resonance, in good agreement with dynamic micromagnetic simulation results. The vortex crystal magnetization configuration and its response to the external magnetic field, were used to explain the isotropic MR behaviour observed.

6.
Scand J Immunol ; 84(5): 284-290, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27507682

RESUMEN

The pathology of schistosomiasis is associated with the formation of granulomas, and this process is associated with liver fibrosis. Studies indicate that Th1 cytokines reduce fibrosis in schistosomiasis, while Th2 cytokines play a part in the progression of fibrosis, and IL-13 has a critical role in this process. The IL-13Rα2 receptor, known as a 'receptor antagonist' binds with high affinity to IL-13, and studies have identified that this plays a part in reducing fibrosis and the size of granulomas. The objective of this study was to evaluate the function of IL-13Rα2 and cellular immune response in hepatic fibrosis. A negative correlation between IL-13Rα2 and IL-13 was found, suggesting an increase in cytokine in early fibrosis. Initially, a negative correlation between IFN-γ and IL-13 was found in patients without fibrosis, and subsequently, this correlation was found to be positive in patients with severe fibrosis, thereby highlighting a new mechanism for regulating the progress of periportal fibrosis. There was a positive correlation between the profiles of Th1 and Th2 cytokines, suggesting the presence of both responses, thus regulating the disease. The results contribute to a better understanding of the immune mechanisms that control the process of hepatic fibrogenesis in schistosomiasis in humans.


Asunto(s)
Subunidad alfa2 del Receptor de Interleucina-13/inmunología , Interleucina-13/inmunología , Cirrosis Hepática/inmunología , Hígado/inmunología , Esquistosomiasis mansoni/inmunología , Anciano , Animales , Brasil , Diagnóstico Precoz , Femenino , Regulación de la Expresión Génica , Humanos , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-13/genética , Subunidad alfa2 del Receptor de Interleucina-13/genética , Interleucina-2/genética , Interleucina-2/inmunología , Interleucina-4/genética , Interleucina-4/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Hígado/parasitología , Hígado/patología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/parasitología , Masculino , Persona de Mediana Edad , Schistosoma mansoni/patogenicidad , Schistosoma mansoni/fisiología , Esquistosomiasis mansoni/complicaciones , Esquistosomiasis mansoni/diagnóstico , Esquistosomiasis mansoni/parasitología , Transducción de Señal , Clase Social , Células TH1/inmunología , Células TH1/parasitología , Células TH1/patología , Balance Th1 - Th2 , Células Th2/inmunología , Células Th2/parasitología , Células Th2/patología , Factores de Tiempo
7.
Genet Mol Res ; 14(3): 11052-62, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26400335

RESUMEN

Leaf disease and ear rot have caused reductions in maize yield in Brazil and other producer countries. Therefore, the aims of this study were to analyze the association between husked ear yield and the severity of maize white spot, gray leaf spot, helminthosporium, and ear rot caused by Fusarium verticillioides and Diplodia maydis using biplots in a mixed-model approach. The responses of 238 lines introduced to Brazil and four controls were evaluated using an incomplete block design with three replicates in two locations: Lavras and Uberlândia, Minas Gerais, Brazil. Two experiments were conducted in each location, one with F. verticillioides and the other with D. maydis. The mixed models elucidated the relationship between yield, leaf disease, and ear disease. Significant genotype x environment and genotype x pathogen interactions were observed. In conclusion, husked ear yield is more associated with ear rot than with the leaf diseases evaluated, justifying the indirect selection for resistance to kernel rot in maize-F. verticillioides and maize-D. maydis pathosystems by yield evaluation.


Asunto(s)
Enfermedades de las Plantas/microbiología , Zea mays/microbiología , Ascomicetos/fisiología , Resistencia a la Enfermedad , Grano Comestible/genética , Grano Comestible/crecimiento & desarrollo , Grano Comestible/microbiología , Fusarium/fisiología , Genes de Plantas , Predisposición Genética a la Enfermedad , Enfermedades de las Plantas/genética , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología , Selección Genética , Zea mays/genética , Zea mays/crecimiento & desarrollo
8.
Nanotechnology ; 26(29): 295303, 2015 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-26135250

RESUMEN

Magnetricity, the magnetic equivalent of electricity, was recently verified experimentally for the first time. Indeed, like the stream of electric charges that produces electric current, emergent magnetic monopoles have been observed to roam freely in geometrically frustrated magnets known as spin ice. However, such phenomena demand extreme physical conditions, say, a single spin ice crystal has to be cooled to very low temperature, around 0.36 K. Candidates to overcome this difficulty are their artificial analogues, the so-called artificial spin ices. Here, we demonstrate that a specific unidirectional arrangement of nanoislands yields a peculiar system where magnetic monopoles emerge and are constrained to move along aligned dipoles, providing an ordered flow of magnetic charges at room temperature.

9.
J Phys Condens Matter ; 27(7): 076004, 2015 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-25640326

RESUMEN

Thermodynamic properties of a spin ice model on a Kagomé lattice are obtained from dynamic simulations and compared with properties in square lattice spin ice. The model assumes three-component Heisenberg-like dipoles of an array of planar magnetic islands situated on a Kagomé lattice. Ising variables are avoided. The island dipoles interact via long-range dipolar interactions and are restricted in their motion due to local shape anisotropies. We define various order parameters and obtain them and thermodynamic properties from the dynamics of the system via a Langevin equation, solved by the Heun algorithm. Generally, a slow cooling from high to low temperature does not lead to a particular state of order, even for a set of coupling parameters that gives well thermalized states and dynamics. At very low temperature, however, square ice is more likely to reach states near the ground state than Kagomé ice, for the same island coupling parameters.

10.
Arq. bras. med. vet. zootec ; 66(6): 1787-1794, 12/2014. tab, graf
Artículo en Portugués | LILACS | ID: lil-735771

RESUMEN

Objetivou-se com este trabalho descrever as medidas biométricas de cordeiros lactantes da raça Santa Inês criados em condições amazônicas; estabelecer relação entre a idade e as medidas corporais; bem como correlacionar essas medidas biométricas com o peso corporal. Utilizaram-se 75 animais criados em sistema semi-intensivo, submetidos a mensurações do peso corporal (PC), comprimento corporal (CC), altura do anterior (AA) e do posterior (AP), perímetro torácico (PT), largura da garupa (LG) e do peito (LP), comprimento da perna (CP), perímetro da perna (PP) e compacidade corporal (COMPC), ao nascer e aos 15, 30, 45 e 60 dias de idade. Somente as medidas LG e PP demonstraram regressões com R2 abaixo de 0,70 em relação à idade dos cordeiros. Todas as medidas corporais utilizadas nesta pesquisa, individualmente, demonstraram r positivo com o peso corporal. As variáveis biométricas que melhor compuseram a equação de predição do peso dos cordeiros utilizados neste estudo foram CC, AP, PT, LG e PP. Concluiu-se que a idade de cordeiros pode ser utilizada como preditora do peso e de algumas medidas biométricas corporais e que o peso pode ser estimado por meio de algumas medidas biométricas...


This study aimed to 1) describe the biometric measurements of Santa Inês lambs until weaning, when raised in the Amazonia conditions; 2) establish the relationship between age and body measurements; and 3) correlate these biometric measurements to body weight. 75 animals submitted to semi-intensive breeding were used, and underwent measurements of body weight (BW), body length (BL), height of the forelimb (HF) and hindlimb (HH), thoracic perimeter (TP), width of rump (WR) and chest (WC), length of leg (LL), perimeter of leg (PL) and more body compacity (COMP), at birth and at 15, 30, 45 and 60 days of age. As a result, the WR and PL measurements demonstrated regressions with R2 below 0.70 in relation to age of lambs. All biometrical measurements used in this study individually demonstrated positive r with body weight. Biometric variables that compose the equation for predicting weight of lambs used in this study were BL, HH, TP, WR and PL. It was concluded that the age of lambs can be used as a predictor of weight and some body biometric measurements. The weight can also be estimated by some biometric measurements...


Asunto(s)
Animales , Identificación Biométrica/estadística & datos numéricos , Identificación Biométrica/métodos , Ovinos/anatomía & histología , Ovinos/crecimiento & desarrollo , Biometría/métodos , Pesos y Medidas Corporales/estadística & datos numéricos , Pesos y Medidas Corporales/veterinaria
11.
J Phys Condens Matter ; 24(29): 296001, 2012 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-22729157

RESUMEN

The energetics of thin elongated ferromagnetic nano-islands is considered for some different shapes, aspect ratios and applied magnetic field directions. These nano-island particles are important for artificial spin ice materials. For low temperature, the magnetic internal energy of an individual particle is evaluated numerically as a function of the direction of a particle's net magnetization. This leads to estimations of effective anisotropy constants for (1) the easy axis along the particle's long direction, and (2) the hard axis along the particle's thin direction. A spin relaxation algorithm together with fast Fourier transform for the demagnetization field is used to solve the micromagnetics problem for a thin system. The magnetic hysteresis is also found. The results indicate some possibilities for controlling the equilibrium and dynamics in spin ice materials by using different island geometries.

12.
Phys Rev Lett ; 88(1): 013201, 2002 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-11800942

RESUMEN

The determination of the right balance between the strong-field interaction of the screened target nucleus and the two-center electron-electron interaction has been controversial since the early attempts to describe the stripping of light, swift ions, by heavy targets. In this work, we find a region of influence for the electron-electron contribution which clearly indicates that this interaction is an essential contribution to the stripping process for both light and heavy targets.

13.
Mem Inst Oswaldo Cruz ; 96 Suppl: 103-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11586433

RESUMEN

In this communication the authors analyzed the pattern of expression of IFN-gamma as a surrogate type 1 response in different clinical forms of schistosomiasis in response to stimulation involving T-cell dependent and T-cell independent pathways, to investigate which pathways were functional in human schistosomiasis, and to further characterize the nature of Th1 response impairment in this parasitic disease.


Asunto(s)
Antígenos CD40/fisiología , Ligando de CD40/fisiología , Interferón gamma/metabolismo , Esquistosomiasis mansoni/metabolismo , Antígenos CD40/metabolismo , Ligando de CD40/metabolismo , Humanos , Inmunidad Celular , Esquistosomiasis mansoni/inmunología , Staphylococcus aureus/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo
14.
Appl Environ Microbiol ; 66(10): 4361-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11010883

RESUMEN

A strategy to measure bacterial functional redundancy was developed and tested with soils collected along a soil reclamation gradient by determining the richness and diversity of bacterial groups capable of in situ growth on selected carbon substrates. Soil cores were collected from four sites along a transect from the Jamari tin mine site in the Jamari National Forest, Rondonia, RO, Brazil: denuded mine spoil, soil from below the canopy of invading pioneer trees, revegetated soil under new growth on the forest edge, and the forest floor of an adjacent preserved forest. Bacterial population responses were analyzed by amending these soil samples with individual carbon substrates in the presence of bromodeoxyuridine (BrdU). BrdU-labeled DNA was then subjected to a 16S-23S rRNA intergenic analysis to depict the actively growing bacteria from each site. The number and diversity of bacterial groups responding to four carbon substrates (L-serine, L-threonine, sodium citrate, and alpha-lactose hydrate) increased along the reclamation-vegetation gradient such that the preserved forest soil samples contained the highest functional redundancy for each substrate. These data suggest that bacterial functional redundancy increases in relation to the regrowth of plant communities and may therefore represent an important aspect of the restoration of soil biological functionality to reclaimed mine spoils. They also suggest that bacterial functional redundancy may be a useful indicator of soil quality and ecosystem functioning.


Asunto(s)
Bacterias/clasificación , ADN Bacteriano/aislamiento & purificación , Ecosistema , Microbiología del Suelo , Bacterias/genética , Bacterias/aislamiento & purificación , Brasil , Conservación de los Recursos Naturales , ADN Bacteriano/genética , ADN Ribosómico/genética , ADN Ribosómico/aislamiento & purificación , Minería , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Contaminantes del Suelo
15.
Arch Pathol Lab Med ; 123(11): 1098-100, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10539915

RESUMEN

CONTEXT: The Epstein-Barr virus (EBV) is a ubiquitous microorganism strongly associated with lymphoproliferative disorders and a large number of human neoplasms, mainly undifferentiated nasopharyngeal carcinoma and Burkitt lymphoma. The viral DNA has been detected in other tumors, such as carcinomas from tonsil, salivary glands, and thymus, and malignancies of the female genital tract. Some authors have proposed that EBV could play a role in the carcinogenesis of cervical tumors; however, other studies do not support this hypothesis. OBJECTIVE: To assess whether EBV is associated with female genital tract neoplasms. DESIGN: Sixty-five biopsy specimens (5 in situ carcinomas, 24 invasive squamous cell carcinomas, 6 lymphoepithelioma-like carcinomas, and 30 endocervical adenocarcinomas) were used to perform EBV detection through RNA in situ hybridization. RESULTS: None of the cervical carcinoma cases studied was positive for EBV infection. CONCLUSIONS: The results suggest that it is still premature to incriminate EBV in the carcinogenesis of cervical carcinoma.


Asunto(s)
Herpesvirus Humano 4/aislamiento & purificación , Neoplasias del Cuello Uterino/virología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Infecciones por Virus de Epstein-Barr/complicaciones , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidad , Humanos , Hibridación in Situ , ARN Viral/genética , Neoplasias del Cuello Uterino/etiología
16.
Arq Bras Cardiol ; 70(6): 409-13, 1998 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-9713083

RESUMEN

PURPOSE: To study the angiographic anatomy of human coronary veins and the possibility of epicardial venous mapping through microelectrode catheters. METHODS: We evaluated 30 patients with sustained ventricular tachycardia using a catheter which provided occlusion of the coronary sinus ostium during venous angiography. They were 25 males, 5 females, ages ranging from 24 to 76 years (mean = 52.7). The veins were studied according to their number, caliber and distribution in the anterior and posterior wall of the left ventricle. RESULTS: Coronary sinus was catheterized in all patients. No discomfort or complication were observed. The number of veins from posterior wall of the left ventricle was 3.1 and anterior wall, 1.9, p < 0.05. The caliber of the coronary veins were: anterior interventricular vein (distal segment = 1.19 +/- 0.22 mm, middle segment = 1.65 +/- 0.35 mm), posterior interventricular vein (distal segment = 1.83 +/- 0.47 mm, middle segment = 2.00 +/- 0.52 mm), left posterior vein (distal segment = 1.45 +/- 0.25 mm, middle segment = 2.49 +/- 0.92 mm); p < 0.05. CONCLUSION: The balloon occlusion technique for coronary venous angiography is feasible and safe. The number and the caliber (distal and middle) of the veins from the posterior wall of the left ventricle were significantly greater than those from the anterior wall. Anatomic conditions for venous epicardial mapping are more adequate in the posterior wall of the left ventricle.


Asunto(s)
Cateterismo Cardíaco , Angiografía Coronaria , Vasos Coronarios/anatomía & histología , Adulto , Anciano , Análisis de Varianza , Electrofisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Flebografía , Estudios Prospectivos , Estadísticas no Paramétricas , Taquicardia Ventricular
17.
Heart ; 79(1): 59-63, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9505921

RESUMEN

OBJECTIVE: To study the value of epicardial mapping through the coronary venous system in patients with sustained ventricular tachycardia. DESIGN: 20 consecutive patients with sustained ventricular tachycardia who were candidates for radiofrequency ablation. SETTING: Electrophysiological laboratory. INTERVENTIONS: Coronary venous angiography was performed with a catheter, which provided coronary sinus occlusion during injection of contrast media. Multipolar microelectrode catheters were then manoeuvred into the tributaries of coronary sinus, using an over-wire system or an on-wire system. An endocardial ablation catheter was positioned in the left ventricle. Conventional programmed ventricular stimulation was performed for sustained ventricular tachycardia induction. Endocardial radiofrequency ablation was performed using impedance or temperature monitoring. RESULTS: Coronary veins were catheterised in all patients; 20 had induction of sustained ventricular tachycardia, 14 were stable. Presystolic epicardial electrograms were recorded in six patients and concealed entrainment in two, helping as a landmark for endocardial ablation. After simultaneous epicardial and endocardial mapping, successful endocardial radiofrequency ablation was achieved in nine of 14 patients with stable ventricular tachycardia (64%). CONCLUSIONS: Epicardial mapping through the coronary veins in patients with ventricular tachycardia is feasible, safe, and can be a useful landmark for endocardial catheter mapping and ablation.


Asunto(s)
Cateterismo Cardíaco , Angiografía Coronaria , Taquicardia Ventricular/fisiopatología , Adulto , Anciano , Estimulación Cardíaca Artificial , Ablación por Catéter , Electrocardiografía , Femenino , Humanos , Masculino , Microelectrodos , Persona de Mediana Edad , Taquicardia Ventricular/cirugía
18.
REBLAMPA Rev. bras. latinoam. marcapasso arritmia ; 10(4): 195-210, out. 1997. ilus, tab
Artículo en Portugués | LILACS | ID: lil-220003

RESUMEN

As arritmias ventriculares têm sido objeto de numerosos estudos multicêntricos nos últimos vinte anos. Os resultados desses estudos modificaram näo só as opçöes terapêuticas atuais, como também motivaram a elaboraçäo de novos ensaios terapêuticos. A populaçäo de coronarianos após o infarto do miocárdio tem sido a mais amplamente estudada. As drogas da classe II foram as únicas que realmente preveniram a mortalidade total em infartados sem taquiarritmias ventriculares sustentadas prévias. Já as drogas da classe I, apesar de serem potentes supressoras de ectopias ventriculares, näo demonstraram reduçäo da mortalidade. No CAST, em um acompanhamento médio de 10 meses, a mortalidade foo maior no grupo tratado (7,7 por cento) que o placebo (3 por cento). Metanálises realizadas com drogas dessa classe mostraram mortalidade maior no grupo tratado (5,6 por cento) que no placebo (4,9 por cento). Quando comparada com o placebi, a amiodarona promoveu uma reduçäo de 33 'por cento' no risco de morte por arritmia no CAMIAT, que acompanhou por 2 anos pacientes infartados com arritmia ventricular complexa. Entretanto a reduçäo da mortalidade total de 18 'por cento' näo foi considerada estatisticamente significante. No EMIAT, comparada com o placebo, a amiodarona tampouco reduziu a mortalidade total em infartados portadores de disfunçäo ventriuclar esquerda. Durante 2 anos de acompanhamento em portadores de miocardiopatia, o GESICA revelou menor mortalidade total em uma populaçäo com apenas 39 'por cento' de coronarianos, 1,2 grupo tratado com a amiodarona. A reduçäo de risco foi de 28 'por cento', quando comparada com o grupo controle. O STAT-CHF näo demostrou reduçäo da mortalidade total em miocardiopatas (71 por cento de coronarianos) comparando o placebo (42 por cento) com a amiodarona (39 por cento) durante um acompanhamento de 2 anos. No grupo de pacientes que sobreviveram à fibrilaçäo ventricular, o CASCADE demonstrou menor mortalidade no grupo tratado impiricamente com a amiodarona quando comparado a drogas da classe I guiadas pelo Holter ou pelo estudo eletrofisiológico. Comparando o D,L sotalol com drogas classe I, o ESVEM demonstrou menor incidência de recorrência da taquicardia ventricular sustentada e menor mortalidade quando comparado com seis drogas da classe I em três anos de acompanhamento. O sucesso da amiodarona e do sotalol no controle das taquicardias sustentadas foi atribuído à combinaçäo da açÝo classe III com a ß - bloqueadora presente nas duas


Asunto(s)
Antiarrítmicos , Arritmias Cardíacas , Complejos Cardíacos Prematuros , Taquicardia Ventricular/terapia , Complejos Prematuros Ventriculares , Ensayos Clínicos como Asunto
19.
Braz J Med Biol Res ; 27(11): 2591-8, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7549981

RESUMEN

1. We describe the isolation of viable merozoites from erythrocytes infected with Babesia bovis or Babesia bigemina organisms by ammonium chloride lysis. 2. Parasite morphology was examined by both light and transmission electron microscopy. Erythrocyte-free parasites maintain their viability and infectivity, retain their antigenicity and are suitable for use in the indirect fluorescent antibody assay.


Asunto(s)
Babesia bovis/aislamiento & purificación , Babesia/aislamiento & purificación , Eritrocitos/parasitología , Cloruro de Amonio , Animales , Anticuerpos Antiprotozoarios/análisis , Babesia/inmunología , Babesia/ultraestructura , Babesia bovis/inmunología , Babesia bovis/ultraestructura , Bovinos , Técnica del Anticuerpo Fluorescente , Microscopía Electrónica
20.
Braz. j. med. biol. res ; 27(11): 2591-8, Nov. 1994. ilus
Artículo en Inglés | LILACS | ID: lil-153980

RESUMEN

1. We describe the isolation of viable merozoites from erythrocytes infected with Babesia bovis or Babesia bigemina organisms by ammonium chloride lysis. 2. Parasite morphology was examined by both light and transmission electron microscopy. Erythrocyte-free parasites maintain their viability and infectivity, retain their antigenicity and are suitable for use in the indirect fluorescent antibody assay


Asunto(s)
Animales , Bovinos , Babesia bovis/aislamiento & purificación , Babesia/aislamiento & purificación , Eritrocitos/parasitología , Anticuerpos Antiprotozoarios/análisis , Babesia bovis/inmunología , Babesia bovis/ultraestructura , Babesia/inmunología , Babesia/ultraestructura , Cloruro de Amonio/farmacología , Técnica del Anticuerpo Fluorescente , Microscopía Electrónica
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...