RESUMO

OBJECTIVES: To evaluate endomyocardial and epimyocardial left ventricular circumferential and longitudinal peak systolic strain and strain rate in dogs with myxomatous mitral valve disease using two-dimensional feature tracking imaging echocardiography. MATERIALS AND METHODS: Epimyocardial and endomyocardial global and regional myocardial peak systolic strain and strain rate using two-dimensional feature tracking imaging were evaluated in healthy dogs and those in stages B1, B2 and C of myxomatous mitral valve disease. Strain and strain rate in circumferential and longitudinal aspect were evaluated in 48 small- and medium-sized dogs. RESULTS: Global endomyocardial circumferential strain and global epimyocardial circumferential strain systolic peak were lower in stage C than in stage B2 (P = 0 · 04 and P = 0 · 02) and similar to healthy dogs. Endomyocardial circumferential strain rate in septal and inferior segments were lower in stage C compared to B2 (P = 0 · 0007 and P = 0 · 0056), but not different from healthy dogs. There were no statistical differences in the epimyocardial circumferential strain rate, longitudinal strain and strain rate between healthy and affected dogs. CLINICAL SIGNIFICANCE: Two-dimensional feature tracking imaging determination of myocardial deformation in epimyocardial and endomyocardial layers allows detection of increased compensatory circumferential left ventricular myocardial systolic performance due to volume overload and absence of this response as disease advances to congestive heart failure.

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RESUMO

Com o intuito de verificar algum dano nas células do miocárdio, utilizaram-se 38 cães, 20 com traçado eletrocardiográfico normal, grupo 1, e 18 com desníveis do segmento ST, grupo 2, em registro na derivação II, velocidade de 50mm/s e sensibilidade N (1mV=1cm). No grupo 1, a dosagem sérica da troponina I (cTnI) destinou-se à obtenção dos valores referenciais (ng/mL) que seriam confrontados com os obtidos no grupo 2. A média e o desvio-padrão foram, respectivamente, 0,16ng/mL e 0,11ng/mL e 0,20ng/mL e 0,11ng/mL, nos grupos 1 e 2. A cTnI não apresentou evidências de associação com idade, massa corpórea, creatinafosfoquinase total e potássio nos dois grupos. Não houve diferenças significativas nos valores de cTnI entre os grupos. Conclui-se que é possível a utilização do kit de ensaio imunométrico quimioluminescente humano para a espécie canina e que a hipóxia-isquemia, revelada pelo desnível do segmento ST não acarreta dano miocárdico ou este é mínimo e indetectável.

In order to investigate myocardial cells injury, 38 dogs were evaluated, being 20 with a normal electrocardiogram (group 1) and 18 with ST segment elevation or depression (group 2), recorded in lead II, at paper speed of 50 mm/sec and N sensibility (1 mV = 1cm). Serum measurement of troponin I (cTnI) in group 1 was determined to obtain reference values (ng/mL). These values were compared to those obtained in dogs from group 2, to confirm or not myocardial injury. Mean cTnI values in groups 1 and 2 were 0.16ng/mL (SD±0.11ng/mL) and 0.20ng/mL (SD±0.11ng/mL), respectively. Three cTnI null values were found in group 1. cTnI was not related to age, mass, CK-T or serum potassium concentration in both animal groups, for each level varied in the group. There was no difference in cTnI values between groups 1 and 2. In conclusion, it is possible to use the human chemiluminescent immunometric assay kit in canine species and hypoxia/ischemia revealed by ST segment deviation does not mean significant myocardium injury.

RESUMO

Com o intuito de verificar algum dano nas células do miocárdio, utilizaram-se 38 cães, 20 com traçado eletrocardiográfico normal, grupo 1, e 18 com desníveis do segmento ST, grupo 2, em registro na derivação II, velocidade de 50mm/s e sensibilidade N (1mV=1cm). No grupo 1, a dosagem sérica da troponina I (cTnI) destinou-se à obtenção dos valores referenciais (ng/mL) que seriam confrontados com os obtidos no grupo 2. A média e o desvio-padrão foram, respectivamente, 0,16ng/mL e 0,11ng/mL e 0,20ng/mL e 0,11ng/mL, nos grupos 1 e 2. A cTnI não apresentou evidências de associação com idade, massa corpórea, creatinafosfoquinase total e potássio nos dois grupos. Não houve diferenças significativas nos valores de cTnI entre os grupos. Conclui-se que é possível a utilização do kit de ensaio imunométrico quimioluminescente humano para a espécie canina e que a hipóxia-isquemia, revelada pelo desnível do segmento ST não acarreta dano miocárdico ou este é mínimo e indetectável.(AU)

In order to investigate myocardial cells injury, 38 dogs were evaluated, being 20 with a normal electrocardiogram (group 1) and 18 with ST segment elevation or depression (group 2), recorded in lead II, at paper speed of 50 mm/sec and N sensibility (1 mV = 1cm). Serum measurement of troponin I (cTnI) in group 1 was determined to obtain reference values (ng/mL). These values were compared to those obtained in dogs from group 2, to confirm or not myocardial injury. Mean cTnI values in groups 1 and 2 were 0.16ng/mL (SD±0.11ng/mL) and 0.20ng/mL (SD±0.11ng/mL), respectively. Three cTnI null values were found in group 1. cTnI was not related to age, mass, CK-T or serum potassium concentration in both animal groups, for each level varied in the group. There was no difference in cTnI values between groups 1 and 2. In conclusion, it is possible to use the human chemiluminescent immunometric assay kit in canine species and hypoxia/ischemia revealed by ST segment deviation does not mean significant myocardium injury.(AU)

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Sixty dogs with idiopathic dilated cardiomyopathy were randomly treated with traditional therapy - digitalis, diuretics, angiotensin-converting inhibitors - (group A) or treated with these drugs plus carvedilol (group B). Echocardiographic variables were measured before and after 3, 13, 26, and 52 weeks of treatment or until death. Comparisons between groups and time were performed. No significant differences between groups were found in the most of the echocardiographic variables. The left ventricular end-systolic diameter indexed to body surface area (LVESDi) increased significantly in the group A dogs compared to the group B animals. The survival of groups A and B dogs were not different (P-value=0.1137). In conclusion, the stability of the LVESDi observed in the group treated with carvedilol may represent the beneficial effect over the ventricular remodeling.

Sessenta cães com cardiomiopatia dilatada idiopática receberam, aleatoriamente, tratamento convencional - digitálicos, diuréticos, inibidores da enzima conversora de angiotensina - (grupo A) ou esses fármacos mais carvedilol (grupo B). As variáveis ecocardiográficas foram avaliadas antes e depois de três, 13, 26 e 52 semanas de tratamento ou até o óbito. Não foram encontradas diferenças significativas entre os grupos de animais quanto à maioria das variáveis ecocardiográficas. O diâmetro sistólico final do ventrículo esquerdo indexado à superfície corpórea (DSVEi) aumentou de forma significativa no grupo A quando comparado ao grupo B. Não se observou diferença na sobrevida dos grupos A e B (P=0,1137). Concluiu-se que a estabilização do DSVEi no grupo tratado com carvedilol pode representar o efeito benéfico deste fármaco sobre o remodelamento ventricular.

Assuntos

RESUMO

Sixty dogs with idiopathic dilated cardiomyopathy were randomly treated with traditional therapy - digitalis, diuretics, angiotensin-converting inhibitors - (group A) or treated with these drugs plus carvedilol (group B). Echocardiographic variables were measured before and after 3, 13, 26, and 52 weeks of treatment or until death. Comparisons between groups and time were performed. No significant differences between groups were found in the most of the echocardiographic variables. The left ventricular end-systolic diameter indexed to body surface area (LVESDi) increased significantly in the group A dogs compared to the group B animals. The survival of groups A and B dogs were not different (P-value=0.1137). In conclusion, the stability of the LVESDi observed in the group treated with carvedilol may represent the beneficial effect over the ventricular remodeling.(AU)

Sessenta cães com cardiomiopatia dilatada idiopática receberam, aleatoriamente, tratamento convencional - digitálicos, diuréticos, inibidores da enzima conversora de angiotensina - (grupo A) ou esses fármacos mais carvedilol (grupo B). As variáveis ecocardiográficas foram avaliadas antes e depois de três, 13, 26 e 52 semanas de tratamento ou até o óbito. Não foram encontradas diferenças significativas entre os grupos de animais quanto à maioria das variáveis ecocardiográficas. O diâmetro sistólico final do ventrículo esquerdo indexado à superfície corpórea (DSVEi) aumentou de forma significativa no grupo A quando comparado ao grupo B. Não se observou diferença na sobrevida dos grupos A e B (P=0,1137). Concluiu-se que a estabilização do DSVEi no grupo tratado com carvedilol pode representar o efeito benéfico deste fármaco sobre o remodelamento ventricular.(AU)

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Caracterizou-se monitorização eletrocardiográfica ambulatorial por 24 horas (ou monitorização Holter) em cães com cardiomiopatia dilatada idiopática, visando principalmente à detecção de arritmias ventriculares não detectadas pela eletrocardiografia convencional (de repouso). Para tanto, avaliaram-se 40 pacientes com diagnóstico de cardiomiopatia dilatada idiopática, por meio de exame físico e mensuração indireta da pressão arterial, além de exames eletrocardiográfico, ecocardiográfico, radiográfico de tórax e da monitorização Holter. Extra-sístoles ventriculares foram detectadas, por monitorização Holter, em 97,5 por cento dos animais e taquicardia ventricular, em 45 por cento. Não houve correlação entre o número de extra-sístoles ventriculares e a fração de encurtamento. Considerando as manifestações clínicas, apenas houve associação entre presença de taquicardia ventricular e histórico de síncopes. Conclui-se que a incidência de arritmias ventriculares em cães com cardiomiopatia dilatada idiopática é bastante alta, sendo a taquicardia ventricular relativamente freqüente, ocorrendo mais sob a forma não sustentada

This study aimed to characterize 24-hour ambulatory electrocardiographic monitoring (Holter monitoring) in dogs with idiopathic dilated cardiomyopathy. Physical examination and indirect (Doppler) blood pressure measurement, and also electrocardiography, thoracic radiography, echocardiography, and 24-hour ambulatory electrocardiographic exams were performed in 40 dogs with idiopathic dilated cardiomyopathy. Ventricular extrasystoles were detected in 97.5 percent of the animals, and ventricular tachycardia in 45 percent. No correlation between the number of ventricular extrasystoles and the shortening fraction was observed. Concerning the clinical symptoms, there was only association between the presence of ventricular tachycardia and past report of syncope. It was concluded that the incidence of ventricular arrhythmias is high in dogs with dilated cardiomyopathy, being ventricular tachycardia, mostly non-sustained, relatively frequent

Assuntos

RESUMO

Caracterizou-se monitorização eletrocardiográfica ambulatorial por 24 horas (ou monitorização Holter) em cães com cardiomiopatia dilatada idiopática, visando principalmente à detecção de arritmias ventriculares não detectadas pela eletrocardiografia convencional (de repouso). Para tanto, avaliaram-se 40 pacientes com diagnóstico de cardiomiopatia dilatada idiopática, por meio de exame físico e mensuração indireta da pressão arterial, além de exames eletrocardiográfico, ecocardiográfico, radiográfico de tórax e da monitorização Holter. Extra-sístoles ventriculares foram detectadas, por monitorização Holter, em 97,5 por cento dos animais e taquicardia ventricular, em 45 por cento. Não houve correlação entre o número de extra-sístoles ventriculares e a fração de encurtamento. Considerando as manifestações clínicas, apenas houve associação entre presença de taquicardia ventricular e histórico de síncopes. Conclui-se que a incidência de arritmias ventriculares em cães com cardiomiopatia dilatada idiopática é bastante alta, sendo a taquicardia ventricular relativamente freqüente, ocorrendo mais sob a forma não sustentada(AU)

This study aimed to characterize 24-hour ambulatory electrocardiographic monitoring (Holter monitoring) in dogs with idiopathic dilated cardiomyopathy. Physical examination and indirect (Doppler) blood pressure measurement, and also electrocardiography, thoracic radiography, echocardiography, and 24-hour ambulatory electrocardiographic exams were performed in 40 dogs with idiopathic dilated cardiomyopathy. Ventricular extrasystoles were detected in 97.5 percent of the animals, and ventricular tachycardia in 45 percent. No correlation between the number of ventricular extrasystoles and the shortening fraction was observed. Concerning the clinical symptoms, there was only association between the presence of ventricular tachycardia and past report of syncope. It was concluded that the incidence of ventricular arrhythmias is high in dogs with dilated cardiomyopathy, being ventricular tachycardia, mostly non-sustained, relatively frequent(AU)

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Avaliaram-se alguns parâmetros ecocardiográficos em modos B, M e Doppler de 27 gatos-do-mato, Leopardus tigrinus, pequeno felídeo selvagem, mantidos em cativeiro e submetidos à anestesia com 1 a 2mg/kg de xilazina e 10mg/kg de quetamina. Observaram-se alterações dos parâmetros cardiovasculares quando os resultados foram comparados aos do gato doméstico (Felis catus) não anestesiado.

Some echocardiographic parameters in B, M-mode and Doppler of 27 Oncillas, Leopardus tigrinus, a wild little feline, kept in captivity and submitted to anesthesia with 1 to 2mg/kg of xilazine and 10mg/kg of ketamine, had been evaluated. Changes of the cardiovascular parameters were observed when the results were compared to non anesthetized domestic cat (Felis catus).

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RESUMO

Avaliaram-se alguns parâmetros ecocardiográficos em modos B, M e Doppler de 27 gatos-do-mato, Leopardus tigrinus, pequeno felídeo selvagem, mantidos em cativeiro e submetidos à anestesia com 1 a 2mg/kg de xilazina e 10mg/kg de quetamina. Observaram-se alterações dos parâmetros cardiovasculares quando os resultados foram comparados aos do gato doméstico (Felis catus) não anestesiado.(AU)

Some echocardiographic parameters in B, M-mode and Doppler of 27 Oncillas, Leopardus tigrinus, a wild little feline, kept in captivity and submitted to anesthesia with 1 to 2mg/kg of xilazine and 10mg/kg of ketamine, had been evaluated. Changes of the cardiovascular parameters were observed when the results were compared to non anesthetized domestic cat (Felis catus).(AU)

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Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in accidental hosts, including humans. Complete genome sequencing of Leptospira interrogans serovar Copenhageni and comparative analysis with the available Leptospira interrogans serovar Lai genome reveal that despite overall genetic similarity there are significant structural differences, including a large chromosomal inversion and extensive variation in the number and distribution of insertion sequence elements. Genome sequence analysis elucidates many of the novel aspects of leptospiral physiology relating to energy metabolism, oxygen tolerance, two-component signal transduction systems, and mechanisms of pathogenesis. A broad array of transcriptional regulation proteins and two new families of afimbrial adhesins which contribute to host tissue colonization in the early steps of infection were identified. Differences in genes involved in the biosynthesis of lipopolysaccharide O side chains between the Copenhageni and Lai serovars were identified, offering an important starting point for the elucidation of the organism's complex polysaccharide surface antigens. Differences in adhesins and in lipopolysaccharide might be associated with the adaptation of serovars Copenhageni and Lai to different animal hosts. Hundreds of genes encoding surface-exposed lipoproteins and transmembrane outer membrane proteins were identified as candidates for development of vaccines for the prevention of leptospirosis.

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Open reading frame expressed sequences tags (ORESTES) differ from conventional ESTs by providing sequence data from the central protein coding portion of transcripts. We generated a total of 696,745 ORESTES sequences from 24 human tissues and used a subset of the data that correspond to a set of 15,095 full-length mRNAs as a means of assessing the efficiency of the strategy and its potential contribution to the definition of the human transcriptome. We estimate that ORESTES sampled over 80% of all highly and moderately expressed, and between 40% and 50% of rarely expressed, human genes. In our most thoroughly sequenced tissue, the breast, the 130,000 ORESTES generated are derived from transcripts from an estimated 70% of all genes expressed in that tissue, with an equally efficient representation of both highly and poorly expressed genes. In this respect, we find that the capacity of the ORESTES strategy both for gene discovery and shotgun transcript sequence generation significantly exceeds that of conventional ESTs. The distribution of ORESTES is such that many human transcripts are now represented by a scaffold of partial sequences distributed along the length of each gene product. The experimental joining of the scaffold components, by reverse transcription-PCR, represents a direct route to transcript finishing that may represent a useful alternative to full-length cDNA cloning.

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Transcribed sequences in the human genome can be identified with confidence only by alignment with sequences derived from cDNAs synthesized from naturally occurring mRNAs. We constructed a set of 250,000 cDNAs that represent partial expressed gene sequences and that are biased toward the central coding regions of the resulting transcripts. They are termed ORF expressed sequence tags (ORESTES). The 250,000 ORESTES were assembled into 81,429 contigs. Of these, 1, 181 (1.45%) were found to match sequences in chromosome 22 with at least one ORESTES contig for 162 (65.6%) of the 247 known genes, for 67 (44.6%) of the 150 related genes, and for 45 of the 148 (30.4%) EST-predicted genes on this chromosome. Using a set of stringent criteria to validate our sequences, we identified a further 219 previously unannotated transcribed sequences on chromosome 22. Of these, 171 were in fact also defined by EST or full length cDNA sequences available in GenBank but not utilized in the initial annotation of the first human chromosome sequence. Thus despite representing less than 15% of all expressed human sequences in the public databases at the time of the present analysis, ORESTES sequences defined 48 transcribed sequences on chromosome 22 not defined by other sequences. All of the transcribed sequences defined by ORESTES coincided with DNA regions predicted as encoding exons by genscan. (http://genes.mit.edu/GENSCAN.html).

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The upstream activating region that controls cellulose-induced expression of the glucose-repressible cellobiohydrolase I gene (UARcb1) of the filamentous fungus Trichoderma reesei is shown to mediate transcription and glucose repression of a reporter gene in Saccharomyces cerevisiae, a unicellular microorganism that lacks the genes required for the utilization of cellulose. Glucose-controlled transcription mediated by UARcb1 requires the products of the genes SNF1 and SSN6, a protein kinase and a repressor, respectively, that regulate glucose-repressible yeast genes. Previously, it has been shown that mitochondrial function is implicated in cellobiohydrolase I gene expression in T. reesei and this sensitivity to the metabolic state of the mitochondria was shown to be transcriptionally controlled by the 5'-flanking sequence of the cbh1 gene [Abrahão-Neto et al. (1995) Biochemistry 34, 10456-10462]. Remarkably, transcription of the reporter gene controlled by UARcb1 in S. cerevisiae also showed a requirement for active mitochondria, suggesting that a common mechanism involving mitochondrial activity controls glucose-repressible genes in both microorganisms.

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The expression of the cellulase transcripts of Trichoderma reesei is controlled by the nature of the energy carbon sources used in the culture medium. Cellulose and the soluble disaccharide sophorose, but not glycerol or glucose, act as inducers. Evidence is presented suggesting that a low constitutive extracellular cellulolytic system catalyzes the formation of a soluble inducer from cellulose, and this inducer triggers the expression of the cellulase transcripts. This basal and cellulose-induced expression of the cellobiohydrolase I mRNAs (cbh1), the major member of the cellulase system, is transcriptionally controlled by two independent cis-acting DNA regions. In addition, expression of the cbh1 transcript is influenced by the physiological state of the mitochondria and this sensitivity is controlled through the 5'-flanking DNA sequence of this gene.

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RESUMO

The expression of the cellulase transcripts of Trichoderma reesei is controlled by the nature of the energy carbon sources used in the culture medium. Cellulose and the soluble disaccharide sophorose, but not glycerol or glucose, act as inducers. Evidence is presented suggesting that a low constitutive extracellular cellulolytic system catalyzes the formation of a soluble inducer from cellulose, and this inducer triggers the expression of the cellulase transcripts. This basal and cellulose-induced expression of the cellobiohydrolase I mRNAs (cbh1), the major member of the cellulase system, is transcriptionally controlled by two independent cis-acting DNA regions. In addition, expression of the cbh1 transcript is influenced by the physiological state of the mitochondria and this sensitivity is controlled through the 5,-flanking DNA sequence of this gene.

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