RESUMO
In spinal muscular atrophy (SMA), mutations in or loss of the Survival Motor Neuron 1 (SMN1) gene reduce full-length SMN protein levels, which leads to the degeneration of a percentage of motor neurons. In mouse models of SMA, the development and maintenance of spinal motor neurons and the neuromuscular junction (NMJ) function are altered. Since nifedipine is known to be neuroprotective and increases neurotransmission in nerve terminals, we investigated its effects on cultured spinal cord motor neurons and motor nerve terminals of control and SMA mice. We found that application of nifedipine increased the frequency of spontaneous Ca2+ transients, growth cone size, cluster-like formations of Cav2.2 channels, and it normalized axon extension in SMA neurons in culture. At the NMJ, nifedipine significantly increased evoked and spontaneous release at low-frequency stimulation in both genotypes. High-strength stimulation revealed that nifedipine increased the size of the readily releasable pool (RRP) of vesicles in control but not SMA mice. These findings provide experimental evidence about the ability of nifedipine to prevent the appearance of developmental defects in SMA embryonic motor neurons in culture and reveal to which extent nifedipine could still increase neurotransmission at the NMJ in SMA mice under different functional demands.
Assuntos
Atrofia Muscular Espinal , Nifedipino , Animais , Camundongos , Diferenciação Celular , Modelos Animais de Doenças , Neurônios Motores/metabolismo , Atrofia Muscular Espinal/tratamento farmacológico , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Nifedipino/farmacologia , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Transmissão SinápticaRESUMO
Aplastic anemia is a rare complication of viral hepatitis. We present 3 cases of hepatitis-associated aplastic anemia after hepatitis A virus infection. One of our cases is the first reported case of hepatitis-associated aplastic anemia after fulminant hepatitis A infection. Patient characteristics were consistent with older reports with regard to age and sex. All 3 patients were male individuals under the age of 20. In addition, all 3 patients had A+ blood group. Outcomes in our series were poor because of the unavailability of antithymocyte globulin and bone marrow transplantation.
Assuntos
Anemia Aplástica/etiologia , Hepatite A/complicações , Sistema ABO de Grupos Sanguíneos , Adolescente , Vírus da Hepatite A , Humanos , Masculino , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Cardiovascular manifestations associated with Addison's disease are previously documented. We described a case of an 11-year-old girl who developed dilated cardiomyopathy as a complication to Addison's disease. Glucocorticoid replacement therapy resulted in near-complete recovery of cardiac function. It is the first reported case of reversible cardiomyopathy as a complication of primary adrenal insufficiency in Syria. CASE PRESENTATION: An 11-year-old Caucasian girl with no significant past medical history presented with abdominal pain, vomiting after meals, and a low-grade fever. A physical examination and laboratory evaluation suggested primary adrenal insufficiency. An echocardiogram showed changes consistent with dilated cardiomyopathy. Causes of primary adrenal insufficiency other than autoimmune were excluded. CONCLUSIONS: Dilated cardiomyopathy is a rare complication of primary adrenal insufficiency. Proper treatment of adrenal insufficiency with glucocorticoid replacement therapy resulted in restoration of normal cardiac function.