RESUMO
A distocia é frequente na clínica reprodutiva e uma das causas responsáveis pela mortalidade neonatalna espécie canina. Nestes últimos 15 anos, diversas pesquisas permitiram o avanço nos conhecimentos sobre aetiopatogenia e o monitoramento, bem como nas formas de tratamento de cadelas de raças de diferentestamanhos em distocia. O objetivo deste trabalho é relatar novas opções para cadelas em distocia, com vistas aminimizar a taxa de mortalidade neonatal.
The dystocia is frequent in the reproductive clinic, and one of the causes responsible for neonatalmortality in dogs. In the last fifteen years, several researchs led to advances in knowledge of the pathogenesis,monitoring, as well as in the treatment of bitches from diferent breed sizes in dystocia. The objective of this studyis to report the new approaches (options) to the bitch in dystocia, in order to minimize neonatal mortality rate.
Assuntos
Feminino , Animais , Cães , Cães/anormalidades , Cães/embriologia , Distocia/história , Distocia/veterináriaRESUMO
A distocia é frequente na clínica reprodutiva e uma das causas responsáveis pela mortalidade neonatalna espécie canina. Nestes últimos 15 anos, diversas pesquisas permitiram o avanço nos conhecimentos sobre aetiopatogenia e o monitoramento, bem como nas formas de tratamento de cadelas de raças de diferentestamanhos em distocia. O objetivo deste trabalho é relatar novas opções para cadelas em distocia, com vistas aminimizar a taxa de mortalidade neonatal.(AU)
The dystocia is frequent in the reproductive clinic, and one of the causes responsible for neonatalmortality in dogs. In the last fifteen years, several researchs led to advances in knowledge of the pathogenesis,monitoring, as well as in the treatment of bitches from diferent breed sizes in dystocia. The objective of this studyis to report the new approaches (options) to the bitch in dystocia, in order to minimize neonatal mortality rate.(AU)
Assuntos
Animais , Feminino , Cães , Distocia/história , Distocia/veterinária , Cães/anormalidades , Cães/embriologiaRESUMO
A series of 117 cases of Pierre Robin Sequence are classified as isolated (48%), syndromic (35%), and with associated anomalies (17%); the latter group had a poor long-term prognosis. In isolated Pierre Robin Sequence, familial cases and a high incidence of twins were noted. Among syndromic Pierre Robin Sequence, 4 syndromes represent more than 50% of the diagnoses.
Assuntos
Síndrome de Pierre Robin/diagnóstico , Síndrome de Pierre Robin/genética , Pré-Escolar , Feminino , Aconselhamento Genético , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Linhagem , Síndrome de Pierre Robin/mortalidade , Prognóstico , Taxa de SobrevidaRESUMO
OBJECTIVE: The objective was to determine the circadian rhythm of melatonin in the Smith-Magenis syndrome (SMS), which causes behavioral problems and sleep disturbance. STUDY DESIGN: Questionnaires, sleep consultations, and sleep diaries were obtained in 20 children with SMS (9 girls, 11 boys aged 4 to 17 years). Actigraphy, electroencephalography, and the circadian variations of plasma melatonin, cortisol, and growth hormone were recorded in 8 patients. Early sleep onset, early sleep offset, and sleep attack indicated sleep disturbance. RESULTS: All children with SMS had a phase shift of their circadian rhythm of melatonin. Time at onset of melatonin secretion was 6 AM +/- 2 (control group: 9 P.M. +/- 2). Peak time was 12 PM +/- 1 (control group: 3:30 AM +/- 1:30), and melatonin offset was at 8 PM +/- 1 (control group: 6 AM +/- 1). Behavioral problems correlated with the inverted circadian rhythm of melatonin. CONCLUSION: Considering that clock genes mediate the generation of circadian rhythms, we suggest that haploinsufficiency for a circadian system gene mapping to chromosome 17p11.2 may cause the inversion of the circadian rhythm of melatonin in SMS.
Assuntos
Anormalidades Múltiplas/genética , Transtornos do Comportamento Infantil/genética , Cromossomos Humanos Par 17 , Ritmo Circadiano , Melatonina/metabolismo , Transtornos do Sono-Vigília/genética , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Deleção de Genes , Humanos , Masculino , Mutação , SíndromeRESUMO
Several mitochondrial diseases are known to occasionally involve the cerebral white matter, namely Leigh syndrome, Kearns-Sayre syndrome, and MELAS syndrome, but in these cases the major finding is alteration in the basal ganglia and brainstem. Here we report on severe diffuse white matter involvement and respiratory chain enzyme deficiency or mitochondrial DNA rearrangement in 5 unrelated families. It is interesting that white matter lesions were the only abnormal neuroradiologic feature in 3 of the 5 families, and multiple small cyst-like white matter lesions were found in 2 of 5 probands. Respiratory chain deficiency should be considered in the diagnosis of severe white matter involvement in childhood.
Assuntos
Encefalomiopatias Mitocondriais/etiologia , Adolescente , Encéfalo/patologia , Criança , Deficiência de Citocromo-c Oxidase , DNA Mitocondrial/genética , Transporte de Elétrons , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Encefalomiopatias Mitocondriais/genética , Encefalomiopatias Mitocondriais/patologia , Fosforilação Oxidativa , Succinato Citocromo c Oxirredutase/deficiênciaRESUMO
Inborn errors of oxidative phosphorylation have been recognized as possible causes of hepatic failure in the neonate, and respiratory enzyme deficiencies have been described in the liver of affected individuals. On the basis of a series of 22 cases, we describe respiratory enzyme deficiency as a cause of early-onset fatal hepatic failure with frequent neurologic involvement. In addition, we have identified a delayed-onset form of hepatic failure with a milder clinical course and inconstant neurologic involvement. Thus we suggest that genetic defects of oxidative phosphorylation be considered as a cause of liver dysfunction in infancy, regardless of the severity of the disease.
Assuntos
Falência Hepática/genética , Erros Inatos do Metabolismo/genética , Complexos Multienzimáticos/deficiência , Fosforilação Oxidativa , Alanina Transaminase/metabolismo , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Falência Hepática/enzimologia , Falência Hepática/mortalidade , Erros Inatos do Metabolismo/enzimologia , Complexos Multienzimáticos/metabolismoRESUMO
We report a mitochondrial DNA deletion (2.6 kb) in a boy with tubulointerstitial nephritis in whom chronic renal failure and leukodystrophy subsequently developed. Elevated lactate values in plasma and cerebrospinal fluid were suggestive of a defect in the mitochondrial respiratory chain. High amounts of deleted mitochondrial DNA were present in muscle and cerebral white matter. On the basis of this observation, we suggest giving consideration to genetic defects of oxidative phosphorylation in any attempt to determine the origin of unexplained chronic tubulointerstitial nephritis, especially when seemingly unrelated organs are involved.
Assuntos
Doença de Canavan/diagnóstico , DNA Mitocondrial/análise , Deleção de Genes , Nefrite Intersticial/etiologia , Sequência de Bases , Encéfalo/enzimologia , Encéfalo/patologia , Doença de Canavan/complicações , Doença de Canavan/genética , Doença de Canavan/patologia , Criança , Doença Crônica , Transporte de Elétrons/fisiologia , Humanos , Falência Renal Crônica/etiologia , Masculino , Dados de Sequência Molecular , Músculo Esquelético/enzimologia , Músculo Esquelético/patologia , Nefrite Intersticial/complicações , Nefrite Intersticial/patologiaRESUMO
Considering the high proportion of unexplained hypertrophic cardiomyopathies on the one hand and the occurrence of cardiomyopathies in several mitochondrial disorders on the other, we hypothesized that isolated hypertrophic cardiomyopathies in infancy could occasionally be the result of defects of oxidative phosphorylation. By means of a scaled-down technique, we were able to investigate oxidative phosphorylation on minute amounts of endomyocardial tissue (1 mg) in three patients with concentric hypertrophic cardiomyopathy (shortening fraction in diameter, 18% to 27%; normal mean +/- 1 SD, 33 +/- 3%) and in control subjects. Although the absolute respiratory chain enzyme activities in the endomyocardial biopsy specimens of the patients were within the low normal range, the determination of the activity ratios allowed us to ascribe hypertrophic cardiomyopathies to respiratory chain enzyme abnormalities in all three cases (complex I, two cases; multiple enzyme deficiency, one case). The respiratory chain enzyme activity ratios, which are normally constant irrespective of the tissue tested, were markedly abnormal in all three patients (cytochrome c oxidase/reduced nicotinamide-adenine dinucleotide cytochrome c reductase, 4.6 to 10.4; normal mean +/- 1 SD, 2.9 +/- 0.5). We conclude that mitochondrial disorders should be regarded as potential causes of hypertrophic cardiomyopathy in early infancy. Because cardiac catheterization is routinely performed for hemodynamic investigation of cardiomyopathies, we suggest that endomyocardial biopsies be considered as a tool for early detection of mitochondrial cardiomyopathies, especially in hypertrophic forms of the disease.
Assuntos
Cardiomegalia/metabolismo , Endocárdio/patologia , Mitocôndrias Cardíacas/enzimologia , Miopatias Mitocondriais/patologia , Biópsia , Cardiomegalia/etiologia , Cardiomegalia/patologia , Transporte de Elétrons , Endocárdio/enzimologia , Endocárdio/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mitocôndrias Hepáticas/enzimologia , Miopatias Mitocondriais/complicações , Miopatias Mitocondriais/metabolismo , Fosforilação Oxidativa , Estudos ProspectivosRESUMO
We report two unrelated children with onset of chronic diarrhea and villous atrophy in the first years of life. Elevated plasma lactate concentrations and lactate/pyruvate and ketone body molar ratios suggested a genetic defect of oxidative phosphorylation. Analysis of the mitochondrial respiratory chain showed a complex III deficiency in muscle of both patients. Southern blot analysis provided evidence of heteroplasmic mitochondrial DNA rearrangements that involve deletion and deletion-duplication. Directly repeated sequences (10 and 11 base pairs, respectively) were present in the wild type of mitochondrial genome at the boundaries of the deletion. Neither parent of either patient had rearranged molecules in their circulating lymphocytes. It appears that a mitochondrial disorder can have chronic diarrhea and villous atrophy as the initial clinical feature. On the basis of these observations, we suggest that genetic defects of mitochondrial energy supply be considered in elucidating the origin of unexplained chronic diarrheas, especially when other, unrelated symptoms occur in the course of the disease.
Assuntos
DNA Mitocondrial , Diarreia Infantil/genética , Complexo III da Cadeia de Transporte de Elétrons/deficiência , Deleção de Genes , Rearranjo Gênico , Intestinos/patologia , Atrofia , Sequência de Bases , Doença Crônica , Diarreia Infantil/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Humanos , Lactente , Dados de Sequência Molecular , NADH Desidrogenase/metabolismo , Succinato Citocromo c Oxirredutase/metabolismoRESUMO
3-Methylglutaconic aciduria was detected in four patients with Pearson syndrome, a multitissue disorder with hematologic abnormalities, lactic acidosis resulting from defective oxidative phosphorylation, and deletions in the mitochondrial genome. 3-Methylglutaconic acid may be an additional useful marker for Pearson syndrome and may be a more specific marker than other organic acids identified in this disorder.