Intracranial germ cell tumors are rare tumor entities in childhood and adolescents. Extra- and intracranial germ cell tumors are identical in their histologic pattern and occur in preferential midline localizations such as the pineal and the suprasellar region. Germ cell neoplasms show increasing incidence rates over the last 30 years. The majority of intracranial germ cell neoplasms are germinomas. About 90% of the patients with pure germinomas can be salvaged by radiotherapy alone according to modern protocols. Non-germinomatous malignant CNS-germ cell tumors are considered to have a poor prognosis. In order to improve the survival of patients affected by these tumors different treatment approaches adding chemotherapy to conventional surgery and radiotherapy have been initiated by various study groups throughout the world. Due to the rarity of these neoplasms only a very limited number of patients has been enrolled in each study. In 1993 an international working group on these tumors was established by the International Society of Pediatric Oncology (SIOP).
Limb girdle muscular dystrophy is a group of clinically and genetically heterogeneous disorders inherited in an autosomal recessive or dominant mode. Caveolin-3, the muscle-specific member of the caveolin gene family, is implicated in the pathogenesis of autosomal dominant limb girdle muscular dystrophy 1C. Here we report on a 4-year-old girl presenting with myalgia and muscle cramps due to a caveolin-3 deficiency in her dystrophic skeletal muscle as a result of a heterozygous 136G-->A substitution in the caveolin-3 gene. The novel sporadic missense mutation in the caveolin signature sequence of the caveolin-3 gene changes an alanine to a threonine (A46T) and prevents the localization of caveolin-3 to the plasma membrane in a dominant negative fashion. Caveolin-3 has been suggested to interact with the dystrophin-glycoprotein complex, which in striated muscle fibers links the cytoskeleton to the extracellular matrix and with neuronal nitric oxide synthase. Similar to dystrophin-deficient Duchenne muscular dystrophy, a secondary decrease in neuronal nitric oxide synthase and alpha-dystroglycan expression was detected in the caveolin-3-deficient patient. These results implicate an important function of the caveolin signature sequence and common mechanisms in the pathogenesis of dystrophin-glycoprotein complex-associated muscular dystrophies with caveolin-3-deficient limb girdle muscular dystrophy.
The detailed clinical features and progress of a child with homozygous 22(I) collagen deficiency are described. Clinically, the disease presents as severe progressive Sillence type IlI osteogenesis imperfecta. The main biochemical defect is the synthesis of an abnormal pro 22(I) chain which does not associate with pro a I(I) chains and therefore is not incorporated into triple helical trimers of type I procollagen which can be used to assemble collagen fibres.
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