Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033377 (prolapse)
 11,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The possibility that the nervous system may control bone metabolism has been raised, as neuromediators physiologically conveyed by sympathetic fibers (eg, vasoactive intestinal peptide) influence bone resorption in vitro. In this study, the sympathetic system was inactivated by treating rats with guanethidine (40 mg/kg/day), a sympathetic neurotoxic, for 21 days, after which a wave of osteoclastic resorption was induced along the mandibular buccal cortex. The effects of denervation were assessed 4 days later (corresponding to the peak of resorption in this model). The rats exhibited ptosis soon after starting guanethidine, proving the success of the sympathectomy. This was associated with a significant increase in calcitonin gene-related peptide- (+54%, p < 0.02) and substance P-immunoreactive sensory fibers (+29%,p < 0.02), a known effect of sympathectomy. For the quantitation of the bone parameters, the study zone was divided into a juxta-osseous alkaline phosphatase-positive osteogenic compartment and a nonosteogenic compartment. In the osteogenic compartment, the resorption surface was reduced by 56% (p < 0.001) in the treated animals, together with a fall in the number of osteoclasts (-25%,p < 0.05) and impaired osteoclast access to the bone surface. Tartrate-resistant acid phosphatase-positive (TRAP+) mononuclear preosteoclasts were found only in this compartment; they were reduced by 43% (p < 0.05) by the sympathectomy. No change in non-specific esterase (NSE)+ osteoclast precursors was found. In the nonosteogenic compartment, vasodilation was the only effect of sympathectomy (+80%,p < 0.05); in particular, the number of NSE+ cells was not modified. Our results indicate that: (1) interactions of NSE+ precursors with osteogenic cells are required for their differentiation into TRAP+ preosteoclasts; (2) the sympathetic nervous system is not involved in osteoclast precursor recruitment; but (3) has a significant effect on resorption by inhibiting preosteoclast differentiation and disturbing osteoclast activation. These data suggest that depletion of sympathetic mediators may disturb osteogenic cell-mediated osteoclast differentiation.
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PMID:Chemical sympathectomy impairs bone resorption in rats: a role for the sympathetic system on bone metabolism. 1057 74

Dok ('downstream-of-kinase') family of cytoplasmic proteins play a role in signalling downstream of receptor and non-receptor phosphotyrosine kinases. Recently, a skeletal muscle receptor tyrosine kinase (MuSK)-interacting cytoplasmic protein termed Dok-7 has been identified. Subsequently, we and others identified mutations in DOK7 as a cause of congenital myasthenic syndromes (CMS), providing evidence for a crucial role of Dok-7 in maintaining synaptic structure. Here we present clinical and molecular genetic data of 14 patients from 12 independent kinships with 13 different mutations in the DOK7 gene. The clinical picture of CMS with DOK7 mutations is highly variable. The age of onset may vary between birth and the third decade. However, most of the patients display a characteristic 'limb-girdle' pattern of weakness with a waddling gait and ptosis, but without ophthalmoparesis. Respiratory problems were frequent. Patients did not benefit from long-term therapy with esterase inhibitors; some of the patients even worsened. DOK7 mutations have emerged as one of the major genetic defects in CMS. The clinical picture differs significantly from CMS caused by mutations in other genes, such as the acetylcholine receptor (AChR) subunit genes. None of the patients with DOK7 mutations had tubular aggregates in the muscle biopsy, implying that 'limb-girdle myasthenia (LGM) with tubular aggregates' previously described in literature may be a pathogenic entity distinct from CMS caused by DOK7 mutations.
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PMID:Phenotypical spectrum of DOK7 mutations in congenital myasthenic syndromes. 1743 81

We describe a 34-year-old patient who was admitted with episodic diplopia, ptosis, and swallowing difficulties of 6 months duration. He also had some muscle cramps aggravated by exercise since the age of 20. Bilateral ptosis of the eyelids, normal gaze, rare fasciculations of the tongue, easy fatigability of ocular and bilateral proximal limb muscles, atrophy of the testes, and gynecomastia were found on neurologic examination. Repetitive nerve stimulation studies and jitter measurement disclosed the defect of neuromuscular junction transmission. Acetylcholine receptor binding antibody was not detected. Acetylcholine esterase inhibitors relieved these episodic symptoms. A genetic study that showed an expansion of cytosine-adenine-guanine (CAG) repeat in the first exon of the androgen receptor (AR) confirmed the diagnosis of X-linked recessive spinal and bulbar muscular atrophy (X-SBMA). Thus, this case shows a rare association of ocular myasthenia gravis with X-SBMA.
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PMID:Ocular myasthenia gravis associated with x-linked recessive spinal and bulbar muscular atrophy. 1907 30

Congenital myasthenic syndromes are a genetically and phenotypically heterogeneous group of hereditary disorders affecting neuromuscular junction. Mutations in the gene encoding choline acetyltransferase cause presynaptic defects. The missense mutation I336T has been identified in Turkish population, and most of the cases carrying this mutation present with exercise-induced fatigability and ptosis. Although apneic attacks occur in these cases during febrile illness in childhood, the number of reported respiratory distress episodes during infancy is scarce. Another important feature of these cases is that response to esterase inhibitors is satisfactory. We present a case of congenital myasthenic syndrome with I336T choline acetyltransferase mutation who presented with numerous attacks of respiratory distress in the infancy period. Interestingly, the patient had myopathic findings on electromyography and diazepam decreased severity of apneic attacks. There was also no improvement with esterase inhibitors.
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PMID:Temporary diazepam responsive apneic attacks and congenital myasthenic syndrome. 1928 95