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Query: UMLS:C1762617 (weakness)
 37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

A total of 450 children with nephroblastoma were treated in the children's oncological department of the All-Union Cancer Research Centre, the USSR Academy of Medical Sciences, between 1976 and 1986. Tumour relapses were diagnosed during various terms of postsurgery in 131 (29.1 per cent) of them: true relapses in 58 (44.1); retroperitoneal lymph nodal metastases in 56 (42.7 per cent) and the both patterns in 17 (13.2 per cent) patients. The majority of the children were older than 3 years. The initial and the most common manifestations of nephroblastoma relapses were the following symptoms: weakness and diminished appetite (93.1 per cent) pale skin (78.6 per cent), abdominal pains (77 per cent), enlarged abdomen (73 per cent), a palpable tumour (82.4 per cent), neurological symptomatology: defecation and urination disorders (12.9 per cent), pareses and paralyses of lower extremities (6.8 per cent). Timely usage of diagnostic complex measures (palpation under the control of myorelaxants, ultrasonic and computed tomography, angiography) enables one to diagnose nephroblastoma relapses. Such histological patterns of nephroblastoma as nondifferentiated blastema, sarcomatoid and rhabdoid tumours were considered as prognostically unfavourable ones. More relapses were diagnosed in children over 4 years. Some cases of nephroblastoma relapses are also caused by the operative technique (lumbar incision in nephrectomy) and extension of the tumour (into the adjacent organs and tissues--Stage II disease). Pre- of intraoperative ruptures of tumour capsules is a principal factor contributing to relapses. Radiation and chemotherapy are found to be mandatory for the prevention of the ruptures.
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PMID:[The diagnostic and prognostic characteristics of nephroblastoma recurrences in children]. 216 70

A solitary extranodal malignant lymphoma (non-Hodgkin's lymphoma, centrocytic type) of the sciatic nerve is described in a 64-year-old woman. Whereas previous reports of peripheral nervous system lymphoma have described multifocal lesions and generally an association with systemic lymphomas, in this case the lymphoma was confined to a segment of a peripheral nerve and was not associated with systemic lymphoma. The clinical presentation was a progressive weakness and sensory disturbance in the right leg. Clinical and electrophysiological examination indicated a lesion in the sciatic nerve, and computerised tomography of the right thigh revealed an enlarged distal segment of the sciatic nerve. On surgical exploration, a fusiform tumour of the sciatic nerve was resected. Pathological examination, including immunohistology and electron microscopy revealed a malignant lymphoma. An unusual histological feature was the presence in the tumour and infiltrated nerve of an extracellular eosinophilic non-amyloid material, similar to that occasionally seen in nodal lymphomas. The patient showed no evidence of lymphoma at other sites at the presentation and this has been confirmed at a 9-month review.
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PMID:Solitary extranodal lymphoma of sciatic nerve. 372 34

A study has been made of the structural changes of nodal and paranodal regions of the nodes of Ranvier of peripheral nerves of rats in which marked accumulations of neurofilaments have occurred within axons under the influence of 2,5-hexanediol over 10 weeks. The neurofilamentous masses caused distension of the axon at two points of apparent weakness as they attempted to slide through the axonal constriction at the nodes. Principally, a spiral axonal protrusion pushed into the zone of unattached myelin loops in the proximal paranodal spinous bracelet of Nageotte. This led to a conical widening of the paranodal constriction and considerable attenuation of the overlying myelin. No degeneration of the myelin occurred however. Alternatively, or additionally, a protrusion occurred of the axon at the nodal region which increased the nodal gap width and occasionally compressed and displaced the adjacent distal paranodal constriction which could have led to some obstruction of axoplasmic flow. Swelling of distal paranodal regions occurred later and was usually associated with proximal swelling. It was also accompanied by evidence suggesting transnodal passage of filamentous material. Sometimes, however, striking nodal constriction occurred in association with symmetrical paranodal swelling. These observations suggest that the spiral glial-axonal relationships at nodes of Ranvier are capable of marked deformation that might allow the intra-axonal neurofilamentous masses to move distally. These findings are discussed in relation to the structural features of the paranodal constrictions.
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PMID:Distortions of the nodes of Ranvier from axonal distension by filamentous masses in hexacarbon intoxication. 668 51

The injection of aluminum powder into the cerebrospinal fluid of adult rabbits induced a slowly progressing encephalomyelopathy characterized at first by alteration of posture and then by myoclonic jerks and muscle weakness. Neurofibrillary degeneration was the hallmark of the disease and involved most of the gray areas. Giant axonal swellings were also numerous, particularly in the proximal axonal segment of neurons of the anterior horns. In the anterior horns the number of neurons with neurofibrillary degeneration decreased with time, while the images of neuronophagia increased in number in the rabbits killed in the second and third month after aluminum injection. In these animals there were also pathologic changes in the peripheral nerves and muscles. The peripheral nerve showed wallerian-like degeneration. Furthermore, in some animals, the presence of nodal axonal swellings and of paranodal myelin retraction were expression also of a distal axonopathy. Neurogenic muscular atrophy appeared in animals sacrificed in the second and third month after injection.
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PMID:Progressing encephalomyelopathy with muscular atrophy, induced by aluminum powder. 716 50

A total of 107 patients with cutaneous melanoma had parotidectomies performed by one surgeon over a 6-year period. Twenty-five parotidectomies were therapeutic and 82 were elective. All elective and 18 therapeutic operations entailed superficial lobectomy, and there were 4 total and 3 subtotal therapeutic operations. The facial nerve was completely preserved in 97 operations, partially sacrificed in 8, and totally sacrificed in 2. Neck dissection accompanied all but 1 parotidectomy. The most common postoperative complication was facial nerve dysfunction. A total of 33 of 82 patients had lower lip weakness between 6 months and 5 years after elective parotidectomy. Lymph nodes were pathologically positive in the parotid gland in 27 patients and in the neck in 15 patients. Ten patients had both parotid and neck metastases. Among patients with positive melanoma in the parotid gland who were observed for at least 1 year, 16 received adjuvant postoperative radiotherapy (550 cGy x 5 fractions) and 9 did not. Parotid recurrences developed in 1/16 irradiated and 4/9 nonirradiated patients but this difference was not significant. Overall melanoma-specific survival at 5 years was 64%, with nodal involvement in the neck or parotid gland significantly worsening prognosis (40% survival at 5 years). The roles of elective lymphadenectomy and adjuvant radiotherapy are now being examined in prospective randomized clinical trials.
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PMID:Evaluation of 107 therapeutic and elective parotidectomies for cutaneous melanoma. 797 59

In immunocompromised patients interventional modalities have diagnostic and/or therapeutic purposes--in both cases they are justified on the basis of the frequently aspecific clinical and instrumental findings and because of the clinical need to carry out the most specific treatment as soon as possible. The authors stress the particular weakness of immunocompromised patients to invasive approaches and discuss the indications, contraindications and precautions which must be taken when performing interventional radiologic modalities. Diagnostic imaging uses radioscopy, US and CT for guidance, each of them allowing a rapid percutaneous confirmation of lesion nature, the assessment of infection in a collection, of a neoplastic lesion type, or of the microbiology of an infectious lesion. Interventional modalities are frequently indicated in chest diseases--e.g., for punctures and percutaneous drainage of empyematous pleural collections or of pulmonary abscesses, percutaneous needle biopsies of lung lesions, or endoscopic dilatation of tracheobronchial stenoses. The percutaneous drainage of lung abscesses in immunocompromised patients makes recovery easier. The diagnostic accuracy of the results of needle biopsy is lower in lung infections than in neoplastic lesions. Indications to abdominal interventional procedures are less frequent--i.e., percutaneous drainage of rare abscesses, percutaneous needle biopsy of nodal mesenteric or lumboaortic masses. Some clinical conditions are diagnosed only with invasive radiologic procedures--e.g., ERCP diagnoses sclerosing cholangitis in AIDS. CT is the basic and the best modality to guide percutaneous drainage in both the abdomen and the chest, to assess contraindications or to indicate some specific modes; in some cases even plurifocal abscesses can be treated with a percutaneous imaging approach.
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PMID:[Interventional modalities in immunosuppressed patients]. 820 28

In 1992, a 49-year-old woman was admitted to the hospital because of exertional dyspnea. Three years earlier sarcoidosis had been diagnosed, and the patient was found to have bilateral hilar lymphadenopathy. The eye, skin, and knee joint were also involved. During the second hospital stay, atrial flutter with advanced A-V nodal block, scattered defects on a 201T1 scintigram, and marked cardiomegaly on chest roentgenogram led to the diagnosis of cardiac sarcoidosis. Signs and symptoms of cardiac failure subsided after placement of an artificial cardiac pacemaker, but the patient still complained of mild muscle weakness in the lower extremities on exertion. 67Ga scintigraphy revealed marked accumulation in the lower extremities, and muscle biopsy of the left gastrocnemius revealed numerous epithelioid cell granulomas with muscle fiber degeneration. Oral corticosteroid therapy was effective. A review of the 24 cases of sarcoid myopathy reported in Japan indicated that the male-to-female ratio is 1:3.8. As compared to patients in whom myopathy led to the diagnosis of sarcoidosis, those in whom myopathy developed after sarcoidosis was diagnosed were (1) relatively older, (2) more likely to have multiple organ involvement, and (3) more likely to have cardiac sarcoidosis. Corticosteroids were beneficial in about three quarters of these 16 cases, who received corticosteroid therapy.
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PMID:[Cardiac sarcoidosis with myopathy and advanced A-V nodal block in a woman with a previous diagnosis of sarcoidosis]. 854 84

Castleman syndrome (giant lymph node hyperplasia) is a rare, heterogeneous lymphoproliferative disorder of unknown etiology and pathogenesis. Most cases occur as mediastinal masses, although extrathoracic involvement including nodal and extranodal locations have been reported. The localized variants (solitary lesions) respond well to surgical excision. We report a 10-year-old boy who presented with headache, intermittent fever, and progressive weakness of his legs. MRI imaging showed an enhancing epidural mass with impingement on the spinal cord at the C6-T2 level. Other laboratory abnormalities included anemia, hypergammaglobulinemia, increased erythrocyte sedimentation rate, and cerebrospinal fluid pleocytosis with slightly increased cerebrospinal protein. The mass was partially resected and the histopathology showed lymphoplasmocytic infiltration compatible with Castleman syndrome. There was no evidence of malignancy. Castleman syndrome is the most likely diagnosis in the presence of the associated systemic findings, although the epidural site for lymphoplasmocytic inflammation is atypical.
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PMID:Unusual case of inflammatory spinal epidural mass (Castleman syndrome). 885 3

Radiological staging continues to remain the basis of a critical therapy of malignant lymphoma. As staging system, the Ann Arbor classification with some added modification is used. Up to now, CT is the imaging study of choice for staging and follow-up of cases of lymphoma. In future however, due to the advantages of the MRI, parts of the staging will be performed by MRI only. Imaging studies provide accurate measurement of extent of nodal disease. The detection of extra-nodal disease depends on the growth pattern and on the location. Focal lesions of sufficient size can be readily detected, diffuse infiltration is often missed. Computed tomography precisely reflects pathologic changes of lung involvement, but the findings are not specific. One weakness of the imaging studies is the low detection rate of splenic and hepatic involvement. Staging of gastrointestinal lymphoma has been improved by "hydro-CT" or "Hydro-MRI".
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PMID:[Malignant lymphoma. Diagnosis and after-care in adults with special reference to cross-sectional imaging]. 915 72


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