Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1762617 (weakness)
 37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inbred mice bearing certain alleles at the Mottled locus have defects in connective tissue which result in weakness of skin and of blood vessels. Previous studies have established that cross-links in collagen and elastin are decreased in these animals due to impaired formation of lysine-derived aldehydes. Lysyl oxidase activity in extracts of skin is markedly lower in those prepared from affected animals than control mice. An inhibitor of lysyl oxidase is present in equal amounts in affected and control skins and does not account for diminished activity found in affected animals.
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PMID:Decreased lysyl oxidase activity in the aneurysm-prone, mottled mouse. 1 40

Tremors, mental changes, opsoclonus, muscle weakness, gait ataxia, incoordination, and slurred speech developed in several employees in a Virginia chemical plant during the summer of 1974. Epidemiologic and clinical studies suggested that the chlorinated insecticide chlordecone (Kepone) was responsible. Severity of symptoms seemed directly related to dose and duration of exposure. Five sural nerve and six muscle biopsy specimens were examined by light microscopy and electronmicroscopy. The sural nerves were also evaluated by computerized morphometry, which showed considerable decrease in the number of unmyelinated fibers and lesser abnormalities of myelinated fibers. Compared with the nerves of the control subjects, those of patients may have had an increase in Reich and Elzholz bodies, and a modest increase in endoneurial collagen. There were occasional "collagen pockets," stacks of Schwann cell cytoplasmic membranes, redundant Schwann cell cytoplasmic folds, and fewer unmyelinated axons. The skeletal muscles contained increased amounts of lipofuscin and lipidlike droplets in subsarcolemmal areas and within intermyofibrillary spaces; the significance of this is unknown. Fiber size variability, type I predominance, and type grouping were present in three cases. All results strongly suggest that chlordecone is a neurotoxic agent predominantly affecting Schwann cells and unmyelinated fibers of peripheral nerves.
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PMID:Chlordecone intoxication in man. II. Ultrastructure of peripheral nerves and skeletal muscle. 7 56

Arthrosis is characterized by destructive lesions of cartilage occuring in the pressure areas of the articular surfaces and leading to the denudation and erosion of the sub-chondral bone. At a further stage these lesions are distinguished from cartilage lesions due to aging and correspond to the progressive erosion of a tissue whose cells present mainly signs of degeneration and whose tissue contains few proteoglycans. The histologic appearance of the initial lesions of the cartilage remains a matter of controversy and ambiguity. Some look like fissures in relatively healthy tissues where the cells show signs of proliferation and hyperactivity. Others correspond to the fragmentation of tissues whose cells and connective tissues are severely damaged. The first biochemical changes of cartilage in arthrosis associate a disorder of proteoglycan aggregation and an increase in the water content. The modifications of proteoglycans could be due to the action of proteolytic enzymes or to a lack of synthesis due to changes in chondrocyte glycotransferase. The biochemical changes could be the cause of cartilage destruction following pressures, since they can decrease the resistance of the tissue. They could nevertheless, be secondary to rupture lesions of the collagen, due only to stress. Arthrosis can then be secondary to either a special weakness of the cartilage or abnormal stress factors.
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PMID:[Study of articular cartilage in arthrosis. Histological and biochemical data]. 37 Sep 62

Regarding experimental data on the multi-factorial reduction of the thermostability of collagen, the following sequence of the mechanism of Dupuytren's contracture is discussed: 1. Hereditary or acquired weakness of fibres of the palmar fascia 2. Further disturbance of the physical property of collagen by the cumulative effects of mechanical, i.e. traumatic, influence. 3. By this means an induced stepwise shrinkage of released fascial fibres in body temperature. 4. Stabilisation of the shortening (contracture) by development of collagen. This hypothesis is supported by histological, polarizing-microscopic, electron-microscopic and chemical results.
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PMID:[Aetiology of dupuytren's contracture (author's transl)]. 82 84

Tissue specimen of the aorta was obtained from a patient with Marfan's syndrome after heart surgery. Media and adventitia were carefully separated and subsequently used for biochemical characterization. Aortas from an embryonic calf and from a human adult were used as internal controls. The data clearly indicated that an insufficient synthesis of type I collagen rather than a defect in the formation of cross-links may be the prime cause in this inherited connective tissue disorder. Such a disturbance in the regulation of the genes coding for the different collagen chains may explain the weakness and enhanced extensibility of the blood vessels finally resulting in an aneurysm.
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PMID:The marfan's syndrome. In vitro study of collagen metabolism in tissue specimens of the aorta. 90 58

Seven patients of temporal arteritis with eye involvement have been presented. These cases represent a spectrum of disease from intermittent diplopia with minimal 6th nerve weakness through mild retinal ischemia with recovery to permanent bilateral blindness. Temporal arteritis should be suspected when any form of ocular ischemia is suspected by history or found on examination of an elderly person. An early diagnosis may protect the vision in both eyes if vision is normal at the time of diagnosis. If vision in one eye is decreased because of ischemia, the vision in the other eye can usually be retained if proper therapy is instituted. Furthermore, adequate therapy may even result in improvement in vision in the involved eye. Patients with biopsy proven temporal arteritis should be continued on steroid therapy until the active disease is quiescent. Inactivity should be determined by carefully monitoring the ESR while steroids are being tapered. If the ESR rises, it is indicative of continued inflammation and if steroids are not continued, the eyes remain at risk as seen in Case 5. If the ESR remains elevated for a year or more despite continuation of high steroid levels, consideration should be given to repeating the temporal artery biopsy. Temporal arteritis should be considered in the differential diagnosis of any multisystem disease in older patients. Even central nervous system involvement may occur concomitantly, since the intracranial vessels are not immune from the disease process. Tuberculosis, systemic syphilis and more recently the collagen vascular diseases have been dubbed the "great imitators" and "the protean diseases." We suggest that the same terminology can be applied to temporal arteritis. Temporal arteritis can affect any organ. Moreover, there is a wide spectrum of variation in the degree of involvement of any particular tissue as illustrated by these 7 cases of ocular involvement.
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PMID:Temporal arteritis: a spectrum of ophthalmic complications. 118 Apr 60

A survey of 118 patients seen in the last twenty years in Newcastle upon Tyne forms the basis of this report. All of these 118 patients fulfilled clearly defined clinical, electrophysiological and pathological criteria for the diagnosis of polymyositis: muscle pain, weakness and characteristic EMG and/or muscle biopsy 55%; and characteristic muscle biopsy 17%; muscle weakness and characteristic EMG 7%; muscle weakness and pain, and raised serum CK activity in an established collagen-vascular disease 5%. A smaller group of 25 patients were selected in whom the clinical characteristics, EMG, muscle biopsy and serum enzyme levels were all completely diagnostic of polymyositis. The patients were followed for two months to twenty-six years, with a mean follow-up duration of six years. Analysis was made of the features at presentation and during the course of the illness, and of prognostic factors bearing upon the disability, response to treatment and mortality. Cases were classified according to the system of Rose and Walton (1966). Groups I, II, and III each constituted approximately one-third of the total cases, while only 8% of all cases were associated with carcinoma. The female to male ratio was 1.4:1. Though cases were seen in all age groups, the largest number was in the sixth decade. The sedimentation rate was raised in 55% of cases. Electromyography was characteristic of polymyositis in 45% of cases, and in only 11% was it normal. The serum creatine kinase activity was raised in 64% of cases. There was no correlation between the extent of these abnormalities and the degree of weakness or disability. 65% of muscle biopsies had changes with inflammatory infiltration virtually diagnostic of polymyositis. 17% of cases had a normal muscle biopsy. Most of the patients (89%) were treated with high-dose prednisone therapy, commencing with 30-100 mg/day, gradually reducing to a maintenance dose of 5-15 mg/day over two or three months. All clinical groups showed considerable improvement in average disability with time on "high dose" corticosteroid therapy, the maximum improvement occurring within the first three years. The degree of improvement in disability was considerably less in those inadequately treated, though the mortality rate was similar in the two groups. 66% of all survivors had essentially no functional disability at follow-up three or more years later, and in the majority of these cases the disease appeared to have burned itself out. 33% of cases had significant disability after three years, and in half of these the disease appeared to be still active.
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PMID:Polymyositis: its presentation, morbidity and mortality. 121 71

Interstitial lung disease (ILD) has been recognized as a manifestation of polymyositis or dermatomyositis (PM/DM). Patients with PM/DM with anti-Jo-1 antibody had a higher incidence of ILD. Thirty-five patients with PM/DM were studied the antibodies. Six (16.1%) were found to have them. ILD occurred in all 6 anti-Jo-1 positive patients, as opposed to 10 (34.5%) of 29 anti-Jo-1 negative patients. Only 2 cases of undifferentiated connective tissue disease among 1320 patients with various kinds of collagen vascular diseases other than PM/DM were positive for anti-Jo-1 antibody. These two patients also had lung involvement. Among six PM/DM patients with anti-Jo-1 antibody, dyspnea preceded proximal muscle weakness in three patients. In one case, the anti-Jo-1 antibody had been detected one month prior to the onset of myositis. Anti-Jo-1 antibody is a useful marker for PM/DM with ILD.
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PMID:Anti-Jo-1 antibody in patients with polymyositis/dermatomyositis. 130 48

Skeletal muscle myopathy is a well-known side-effect of systemically administered corticosteroids. In recent years renewed attention is being paid to the involvement of the respiratory muscles and its consequent significance in pulmonary patients. Two different clinical patterns of steroid-induced muscular changes are known. In acute myopathy and atrophy after short term treatment with high doses of steroids, generalized muscle atrophy and rhabdomyolysis occur, including the respiratory muscles. Chronic steroid myopathy, occurring after prolonged treatment with moderate doses, is characterized by the gradual onset of proximal limb muscle weakness and may be accompanied by reduced respiratory muscle force. Animal studies demonstrated diaphragmatic myopathy and atrophy similar to the alterations in peripheral skeletal muscles. Fluorinated steroids induced selective type IIb (fast-twitch glycolytic) fibre atrophy, resulting in changes in contractile properties of the diaphragm. Non-fluorinated steroids may also induce histological, biochemical and functional alterations in the diaphragm. Observations in patients with collagen vascular disorders and with asthma and chronic obstructive pulmonary disease (COPD) underline the potential hazards of treatment with corticosteroids to respiratory muscle structure and function.
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PMID:Steroid-induced myopathy and its significance to respiratory disease: a known disease rediscovered. 142 9

The etiology, pathogenesis and mechanism of optic nerve damage in primary open angle glaucoma (POAG) and low tension glaucoma (LTG) were investigated by experimental glaucoma in monkey and by follow-up studies of many patients over 15 years, by pathohistological and immunohistochemical analysis. 1) LTG was proved to be a real glaucoma, showing pressure-dependent optic nerve damage. The pathological entity was a primary weakness of the lamina cribrosa (LC), and therefore even normal pressure could deform the LC. Due to backward distortion of LC the channels were disarranged and twisted, inducing mechanical optic nerve damage. There was no active vascular damage or vascular constriction at the site of the optic nerve damage. The filling defects of the advanced glaucomatous optic disc were not the cause of optic nerve damage, but the result of regressive vascular change after axon bundle loss. Splinter hemorrhage of the optic disc might be the result of the same process. 2) The weakness of LC might be induced by the abnormal metabolism of the extracellular matrix of the LC. 3) To arrest the progressive optic nerve damage in LTG, the intraocular pressure (IOP) should be maintained under 12, or ideally, 10 mmHg. 4) The optic nerve damage in POAG was not only pressure-dependent, but also dependent on the weakness of the LC, as in the case of LTG. In the early stage the IOP should be under 19 mmHg, in the advanced stage under 14 mmHg in order to arrest progression for over 15 years. 5) In advanced experimental glaucoma of monkeys, the LC showed reduction of elastin, fragmentation of collagen, and change of proteoglycans. 6) As in the LC, the trabecular meshwork also showed abnormal metabolism and abnormal deposits on the extracellular matrix in POAG, and LTG as well. 7) POAG and LTG might belong to the same family in which common abnormal metabolism of LC and trabecular meshwork induce various clinical features.
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PMID:[Primary open angle glaucoma and low tension glaucoma--pathogenesis and mechanism of optic nerve damage]. 148 70


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