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)

The fine structure of gastric epithelial cells of normal rats and of rats restrained at low temperature has been examined by transmission and scanning electron microscopy. The observation of the normal mucosa has revealed that in comparison with the cells overlying the flat surface of the stomach, those covering the plicae have a different surface structure with numerous microvilli and a peculiar organization of intercellular junctions. Restrained animals initially showed swelling of the foveolae that was followed by a detachment of the superficial cells leading to severe stomach erosions. It is postulated that the first modification induced by stress is a decrease in the amount of mucus granules and a weakness of the mucous protective barrier. This was confirmed by the results obtained by pretreating rats with zolimidine. This substance, which has been shown to increase secretion and synthesis of gastric mucus, completely protected the animals from the stress-induced damage of the stomach surface. Furthermore, this treatment produced an enlargement of the cisternae of the endoplasmic reticulum and an increase in the surface of the Golgi apparatus in the epithelial cells.
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PMID:Surface alterations induced by stress in gastric mucosa: protective effect of zolimidine. A transmission and scanning electron microscope investigation. 13 48

The spatio-temporal evolution of peripheral giant axonal degeneration has been studied in rats during the development of concurrent peripheral (PNS) and central (CNS) nervous system dying-back disease after chronic intoxication with the neurotoxic hexacarbons n-hexane (CH3CH2CH2CH2CH2CH3), methyl n-butyl ketone (MBK) (CH3COCH2CH2CH2CH3), or 2,5-hexanedione (CH3COCH2CH2CHOCH3), a neurotoxic metabolite of MBK. Each compound caused animals insidiously to develop identical, symmetrical peripheral neuropathies characterized by eversion and drop of hindfeet, inability to extend hindlimbs and upper extremity weakness. Teased fiber studies demonstrated that giant axonal swellings first developed on the proximal sides of multiple paranodes sited in distal, non-terminal regions of large myelinated fibers. Later, swellings developed at internodal sites. Smaller myelinated and unmyelinated fibers also underwent multifocal, giant axonal swelling. In affected myelinated fibers, swollen nodal and paranodal axons were frequently associated with retracted paranodal myelin sheaths. Adjacent distal internodes were attenuated and corrugated. Demyelinated paranodes apparently underwent local shrinkage and remyelination before complete distal fiber breakdown commenced. The proximal limits of chains of homogeneous myelin ovoids were interfaced with proximal, preserved regions at sites of giant axonal swellings. Regeneration of myelinated axons also occurred during intoxication. Regenerating fibers wre composed of multiple, short, branched internodes which sometimes appeared multifocally swollen. Interfaces between regenerating and preserved portions of fibers were unswollen. Thick section studies showed that pronounced endoneurial edema accompanied fiber degeneration in peripheral nerve trunks. Ultrastructural studies revealed multifocal, giant axonal swellings containing masses of 10 nm neurofilaments and sometimes, clustered mitochondria, neurotubules and smooth endoplasmic reticulum. Enlarged granular mitochondria, interdigitated Schwann cell/axon networks and corrugated myelin sheaths were common findings. Dense granules, vesicles and hexagonal particles were also noted in the axoplasm. These findings provide new insights into the nature of the dying-back process: although there was a retrograde, temporal spread of axonal swelling up affected nerve trunks, axonal degeneration neither began in the nerve terminal nor spread seriatim centripetally along individual nerve fibers. The dying-back process was further examined in a companion study in this issue (32) which analyzed some of the factors determining the differential vulnerability of PNS and CNS fibers in animals intoxicated either with these neurotoxic hexacarbons or with acrylamide.
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PMID:Ultrastructural studies of the dying-back process. III. The evolution of experimental peripheral giant axonal degeneration. 19 Mar 57

An 11-year old boy had had recurrent episodes of hepatic and cerebral dysfunction and underdeveloped musculature. Overt weakness developed at age 10. Lipid excess, especially in type I fibers, was found in muscle. Hypertrophied smooth endoplasmic reticulum and excessive microbodies were present in liver. Marked carnitine deficiency was shown in skeletal muscle, plasma, and liver. Ketogenesis was impaired on a high fat diet, but omega oxidation of fatty acids was enhanced. There was excessive glucose uptake and essentially no oxidation of labeled long-chain fatty acids by perfused forearm muscles in vivo. Oral replacement therapy restored plasma carnitine levels to normal, but not liver or muscle carnitine levels, and was accompanied by clinical improvement.
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PMID:The syndrome of systemic carnitine deficiency. Clinical, morphologic, biochemical, and pathophysiologic features. 23 82

The effects of maytansine (MYT), a naturally occurring ansa macrolide and potent antimitotic drug that binds to tubulin, were studied by light and electron microscopy in the central nervous system of rabbits. Respectively, 17 and 5 animals were sacrified at various time intervals following a single intrathecal or intraocular injection of the agent. The rabbits responded to the intrathecal injection with progressively severe weakness. By 19 h following injection the neurons of the cervical spinal cord, medulla and pons showed, by light microscopy, a marked clumping of the Nissl substance, while on the third day and later the nerve cell perikarya and dendrites displayed severe neurofibrillary changes. By electron microscopy several cytological alterations were observed as early as 19 h; among them were the clumping of the rough endoplasmic reticulum, the reduction in number of microtubules, and the presence of a fine, floccular and amorphous material. The perikaryonal and dendritic neurofibrillary changes appeared as tangles and/or bundles of10 nm neurofilaments. In the intraocularly injected rabbits the earliest changes observed in retinal ganglion cells were the severe reduction in microtubule number and the presence of an amorphous material. The neurofibrillary changes seen at later times were comparable with those observed in the cervical cord and brain stem. Although the molecular events occurring between the formation of the intracytoplasmic MYT-tubulin complexes and the accumulation of filaments are not known, the present results indicate that the proliferation of neurofilaments is chronologically preceded by the reduction in number of the microtubules and by the appearance of an amorphous floccular material in the cytoplasm. It is emphasized that despite differences in binding characteristics and physico-chemical properties, maytansine, colchicine and the Vinca alkaloids have, as a common denominator, the property of interfering with the process of utilization of tubulin and in that way they seem to differ from other chemical agents known to induce neurofibrillary degeneration.
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PMID:Induction of neurofibrillary degeneration following treatment with maytansine in vivo. 58 57

Acid phosphatase activity in particularly organogenic strain of tobacco has been localized in two kinds of tissue: the internal bud primordia and the adjacent tissues. Generally the reactions are weaker in the undifferentiated cells. In differentiating cells, the localization of precipitates from the reaction shows up the continuity of membrane systems such as the endoplasmic reticulum, the nuclear membrane and the vacuoles. The relative weakness of the reactions observed in the vacuoles is in agreement with the rareness of hydrolysis. Parenchymatous cells between the meristems and the surface of the tissue culture undergo autolysis, which seems to help the growth of buds produced by neoformation. Specific and often intense reactions occur in the cell walls.
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PMID:[An ultrastructural study of acid phosphatase activity localized in bud primordia of an organogenic culture of Nicotiana tabacum L. var. P. 19]. 72 86

A 22-year-old housewife was referred to us for review of progressive proximal muscle weakness which started at 15 years of age. A biopsy of left rectus femoris muscle showed acid phosphatase positive vacuoles partly filled with PAS-positive material. Acid maltase activity of the cultured fibroblasts was pathologically low at 0.4 nmol/mg protein considering 161.0 +/- 32.4 nmol/mg protein as a normal range. A diagnosis was made of acid maltase deficiency (juvenile type). Western blot using anti-acid maltase polyclonal antibody revealed 115 and 70 kDa bands in control muscles, where as only the 115 kDa band, a presumable precursor of the enzyme, was visualized in the patient. By immunohistochemistry using the same antibody the epitope was localized to the acid phosphatase positive vacuoles and immunoelectron microscopy demonstrated the acid maltase immunoreactivity within lysosomes. We concluded that the protein precursor unable to proceed into mature enzyme can access to lysosomes from endoplasmic reticulum through Golgi complex in the present case.
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PMID:[A case of acid maltase deficiency (juvenile type)--immunohistochemical and biochemical study]. 130 30

Ultrastructural features of chromatolytic neurons observed in a sporadic case with amyotrophic lateral sclerosis (ALS) are reported. A 70-year-old woman died of weakness and atrophy of the four limbs, bulbar and facial muscles, and hyperreflexia, of 3 1/2 years' duration. Neuronal loss was marked in the anterior horn of the spinal cord, with degeneration of the pyramidal tracts. Most of the remaining neurons showed chromatolysis. Some of the chromatolytic neurons contained faintly eosinophilic inclusions with a halo. Few spheroids were observed. Hypoglossal nuclei, nucleus ambiguus, motor nuclei of N.VII and N.V were well populated, but contained several chromatolytic neurons. Ultrastructurally, the chromatolytic neurons contained aggregates of fibrils thicker than the 10-nm neurofilaments. These fibrils were arranged randomly, and were closely associated with granular materials as well as rough endoplasmic reticulum. Neurofilamentous accumulations reported to be common in sporadic ALS were rare in this case. No Bunina body was observed.
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PMID:Ultrastructural study of chromatolytic neurons in an adult-onset sporadic case of amyotrophic lateral sclerosis. 337 56

A 6-year-old dog which presented with weakness of the hind limbs progressed to a cerebral disorder with altered sensorium. The cerebrospinal fluid (CSF) protein was elevated, but no cells were found. Autopsy revealed severe hemorrhages in the basal nuclei and diencephalon. Histology of the lesions showed many meningeal and parenchymal blood vessels filled with neoplastic mononuclear cells. Electron microscopy of the tumor cells demonstrated ribosomes, granular endoplasmic reticulum, mitochondria, and a few lysosomes. Immunocytochemical procedures to demonstrate Factor VIII-related antigen were negative. This appears to be the first recorded case of cerebral angioendotheliomatosis in domestic animals and closely resembles the syndrome in man.
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PMID:Cerebral angioendotheliomatosis in a dog. 393 4

A 7 1/2-year-old girl with hypermethioninemia, myopathy, and mental deficiency (IQ = 65) is described. The increased methionine was not associated with deficiency of methionine adenosyltransferase, which was normal or increased in liver, muscle, erythrocytes, and cultured fibroblasts. Methionyl-tRNA synthetase in fibroblasts was normal. The hypermethioninemia and a concurrently increased blood S-adenosylmethionine declined on a diet low in methionine. There was a diffuse, symmetrical, moderate proximal muscle weakness, but muscle atrophy was not discernible, and the deep tendon reflexes were hypoactive but obtainable. Electromyographic abnormalities were not detected. Electron microscopy of muscle revealed 3 to 6 small myelin figures in the region of the I band in nearly every fiber, with occasional myelin figures at other sites also. These myelin figures were more numerous and smaller than those seen accompanying nonspecific myopathies and may reflect a more specific pathological change. Electron microscopy of liver revealed three nonspecific lesions in all hepatocytes: (1) numerous megamitochondria with crystalloid deposit in the matrix; (2) increased numbers of small vesicles of smooth endoplasmic reticulum; and (3) loss of plasma membrane microvilli, with extensive bleb formation and shedding of cytoplasm into Disse's space.
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PMID:Methioninemia and myopathy: a new disorder. 727 Dec 38

We reported a case of a fifteen-year-old boy with metatropic dysplasia. He showed short-limbed dwarfism at the age of 1 year and 2 months. Roentgenograms of the bone revealed generalized platyspondyly, enlargement of the epiphyseal-metaphyseal regions of long bones and halberd-shaped pelvis. Scoliosis progressed and he evolved to short-trunk dwarfism. When he was 10 years old, he developed gait disturbance gradually due to muscle weakness of lower extremities. He was examined at the age of 15 years. Motor nerve conduction velocity was reduced to 21 m/sec in left median nerve and 18.5 m/sec in left peroneus nerve. Needle EMG showed neurogenic pattern. We performed sural nerve biopsy and obtained histopathological findings. Fiber density of myelinated axons decreased. Electron microscopic examination revealed onion bulb formation surrounding a myelinated fiber and a storage in the rough-surfaced endoplasmic reticulum of Schwann cell. These inclusions were similar to those of cartilage of his long bone. We supposed that the neuropathy would have relation to this bone dysplasia.
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PMID:[A case of motor and sensory neuropathy associated with metatropic dysplasia]. 818 80


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