The congenital muscular dystrophies (CMD) are a heterogeneous group of autosomal recessive disorders. A new pathomechanism has recently been identified in a group of these disorders in which known or putative glycosyltransferases are defective. Common to all these conditions is the hypoglycosylation of alpha-dystroglycan. Fukuyama CMD, muscle-eye-brain disease and Walker-Warburg syndrome, each associated with eye abnormalities and neuronal migration defects, result from mutations in fukutin, POMGnT1 and POMT1, respectively, while mutations in the fukutin-related protein (FKRP) gene cause congenital muscular dystrophy 1C, typically lacking brain involvement. Another putative glycosyltransferase, Large, is mutated in the myodystrophy mouse. The human homologue of this gene is therefore a strong candidate for involvement in novel forms of muscular dystrophy. We studied 36 patients with muscular dystrophy and either mental retardation, structural brain changes or abnormal alpha-dystroglycan immunolabelling, unlinked to any reported CMD loci. Linkage analysis in seven informative families excluded involvement of LARGE but sequencing of this gene in the remaining 29 families identified one patient with a G1525A (Glu509Lys) missense mutation and a 1 bp insertion, 1999insT. This 17-year-old girl presented with congenital muscular dystrophy, profound mental retardation, white matter changes and subtle structural abnormalities on brain MRI. Her skeletal muscle biopsy showed reduced immunolabelling of alpha-dystroglycan. Immunoblotting with an antibody to a glycosylated epitope demonstrated a reduced molecular weight form of alpha-dystroglycan that retained some laminin binding activity. This is the first description of mutations in the human LARGE gene and we propose to name this new disorder MDC1D.

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Celiac disease and gastric HP infection have inverse relationship that raises the question whether development of HP infection confers protection against CD.

A 5-year-old Indian boy presented with subacute onset regression of milestones associated with seizures and spasticity. The symptoms started after an attack of measles. The magnetic resonance imaging (MRI) of the brain showed cavitating leukodystrophy with posterior predominance. Molecular analysis of the APOPT1 gene, a recently described gene associated with mitochondrial leukodystrophy, showed the patient to be homozygous for a 12.82-kilobase deletion, including coding exon 3. Deletion of exon 3 produces a frameshift, predicting the translation of a truncated protein (p.Glu121Valfs*4). The patient was started on mitochondrial cocktail regimen of thiamine, riboflavin, coenzyme Q and carnitine. Although he initially showed some improvement, he died 6 months after the onset of his illness.

Background:Olfactory neuroblastoma (ONB) is a rare malignant neuroectodermal tumor of the nasal cavity. Mixed olfactory neuroblastoma which contains areas of divergent differentiation is even rare. Till date, only 4 cases of mixed olfactory neuroblastomas have been reported.Case Description:We report the case of a 46-year-old male who presented with the chief complaints of nasal bleeding and nasal obstruction since 4 months. Radiological imaging was suggestive of a large heterogeneous mass in the left superior nasal cavity with extensions into bilateral maxillary, ethmoidal, and sphenoidal sinuses, as well as into the anterior cranial fossa. Bifrontal osteoplastic craniotomy and excision of the intracranial part of the tumor from above and transnasal endoscopic removal of the mass in the nasal cavities and paranasal sinuses from below was done. Postoperative radiological imaging was suggestive of gross complete excision of the mass. Histopathological diagnosis was “mixed olfactory neuroblastoma-carcinoma (squamous and glandular differentiation) Hyams grade IV.” On immunohistochemistry, the tumor cells were positive for neuron specific enolase (NSE), synaptophysin, chromogranin, and CD56 and peripherally for S100. Because of personal reasons, the patient did not take adjuvant radiotherapy. He presented again after 2 months with a full blown recurrence of esthesioneuroblastoma with similar extensions as before. The patient is now planned for salvage surgery followed by adjuvant chemoradiation.Conclusion:We report the 5th case in the world of mixed olfactory neuroblastoma-carcinoma with squamous and glandular differentiation. From an analysis of the findings in the 5 reported cases of mixed olfactory neuroblastomas, one might infer that a separate subcategory of ONB, i.e., mixed ONB, should be considered because mixed ONBs have an aggressive behavior, high rates of recurrence, and these tumors should be treated aggressively by multimodality treatment.