Protein kinase C (PKC) is a multigene family of at least ten isoforms, nine of which are expressed in brain (alpha, betaI, betaII, gamma, delta, straightepsilon, eta, zeta, iota/lambda). Our previous studies have shown that many of these PKCs participate in synaptic plasticity in the CA1 region of the hippocampus. Multiple isoforms are transiently activated in the induction phase of long-term potentiation (LTP).
View Article and Find Full Text PDFPeripheral arterial embolism arising from a malignant tumour is an infrequent manifestation of neoplastic disease and also a rare cause of acute arterial occlusion. A case of recurrent arterial embolism of the lower extremities due to a primary lung cancer is reported and the literature on this topic is reviewed.
View Article and Find Full Text PDFRationale And Objectives: The authors investigated whether hormonally active and inactive pituitary adenomas can be discriminated in vitro by magnetic resonance (MR) imaging-related data.
Methods: 1/T1 nuclear magnetic relaxation dispersion profiles were measured for 39 fresh surgical specimens of secreting and nonsecreting adenomas, classified using clinical criteria or preoperative serum hormone levels. Nonsecreting adenomas were subdivided into hormone-producing and nonhormone-producing by immunostains.
Rationale And Objectives: Water content and water-proton relaxation rates are reported for fresh, histologically characterized, surgical specimens of calcified human intracranial meningiomas and compared with results for noncalcified meningiomas from an earlier study and with calcium hydroxyapatite (CaHA) suspensions to elucidate the influence of calcification on magnetic resonance imaging (MRI) signal intensity of calcified meningiomas.
Methods: The magnetic field dependence of 1/T1 of water protons (nuclear magnetic relaxation dispersion profile) and dry weights are reported for 38 calcified nonhemorrhagic and 3 hemorrhagic specimens of known histologic subtype, a subset of the 67 specimens measured earlier. Calcification was considered mild or heavy when the dry weight was within or above the range for noncalcified meningiomas.
This immunohistochemical study compares the localization of the neuronal class III beta-tubulin isotype (beta III) to that of the proliferating cell nuclear antigen (PCNA)/cyclin in 46 cerebellar neuroblastic tumors (medulloblastomas). Both class III beta-tubulin (beta III) and PCNA/cyclin reactivities were present in all tumors, but the topographic distribution and cytomorphologic features of stained cells varied considerably between classic and desmoplastic medulloblastomas. Four neoplastic phenotypes, representing gradations of neuronal differentiation, were identified: [Allegranza 1991] apolar, blast-like PCNA/cyclin(+) cells devoid of beta III reactivity (Nb1); [Bravo et al.
View Article and Find Full Text PDFRationale And Objectives: Resected meningiomas were examined by relaxometry and light microscopy to evaluate the potential of magnetic resonance imaging (MRI) for identifying histologic subtypes and for discriminating among benign, radiation therapy-induced, and malignant meningiomas.
Methods: The magnetic field dependence of 1/T1 of water protons (nuclear magnetic relaxation dispersion [NMRD] profile) and the water content (dry weight) were measured for 67 specimens, and the data were compared with histology. Only noncalcified, nonhemorrhagic meningiomas are reported.
The major unifying concept of the effect of trauma on the central nervous system is the application of force to the brain. The mode of delivery of energy and its dissipation result in the varying pathologic manifestations of hemorrhage, contusions, or tears. Topics discussed in this article include inner cerebral trauma, gunshot wounds, contusions and lacerations, hemorrhages, fractures, and spinal cord trauma.
View Article and Find Full Text PDFThe magnetic relaxation rate 1/T1 of tissue water protons was measured over a wide range of magnetic field strengths (NMRD profile) for 92 fresh surgical specimens of astrocytomas to search for correlations of 1/T1 with tumor histology, as determined by light microscopy, and to assess the diagnostic potential of NMRD profiles for grading astrocytomas. A third goal was to elucidate the molecular determinants of 1/T1. Each specimen was histologically graded and inspected for evidence of mineral deposits (Ca, Fe); its dry weight was determined and expressed in % of original wet weight.
View Article and Find Full Text PDFThis is the first description of GS guinea pigs, a partially inbred, non-ataxic, albino Peruvian (long-hair) strain with abnormal motor behavior and seizures. GS guinea pigs show gross and microscopic cerebellar and microscopic cerebrocortical abnormalities compared to Hartley strain animals. There is little difference between GS and short-hair guinea pig strains in Purkinje cell function, electrically evoked Ca2+ transients or immune responsiveness.
View Article and Find Full Text PDFThe authors have measured the magnetic field dependence of 1/T1 (nuclear magnetic relaxation dispersion, or NMRD profiles) of water protons of histologically characterized samples of astrocytomas, meningiomas, and lymphomas. The goal was to elucidate the determinants of 1/T1 of brain tumors at the cellular level and, in particular, to search for a possible correlation of the profiles with neoplastic properties, including degree of malignancy. Because of the recently demonstrated contribution of myelin to 1/T1 of white matter, careful histologic analyses were performed to correct for its presence.
View Article and Find Full Text PDFClin Sports Med
January 1984
Twenty-four male members of the 1976 United States Olympic Fencing Squad were profiled. Data were collected on anthropometry; flexibility; and muscular strength, endurance, and power. Five of the physical variables measured in the laboratory were shown to have a significant relationship to competitive success.
View Article and Find Full Text PDFA musculoskeletal profiling study was done on 24 members of the U. S. Pan American and Olympic fencing squads.
View Article and Find Full Text PDFA 26-year-old man with lymphomatoid granulomatosis (LYG) was found at postmortem examination to have an immunoblastic sarcoma involving the central nervous system. Residual evidence of LYG was present only in the lungs at autopsy. Studies for intracellular immunoglobulin utilizing the immunoperoxidase technique showed a marked polyclonal reaction in sections of lymph nodes and occasional cells in the cellular central nervous system tumor that stained for intracellular immunoglobulins (IgG, IgM and both kappa and lambda).
View Article and Find Full Text PDFA case of intracranial Burkitt's lymphoma is reported in a child whose symptoms began at 3 months of age with a definite histologic diagnosis established at 18 months. Serologic studies demonstrated high antibody titers to Epstein-Barr virus (EBV) in the patient and in four out of five members of the immediate family. The patient also demonstrated immunity to antigens derived from African Burkitt's lymphoma cell lines.
View Article and Find Full Text PDFTwo adult Ashkenazi Jewish siblings have had slowly progressive deterioration of gait and posture since early childhood, distal to proximal muscle atrophy, pes cavus, foot drop, spasticity, mild ataxia of limbs and trunk, dystonic features, and dysarthria. Vision and optic fundi are normal, verbal intelligence is stable, and no seizures have occurred. The sister of the patients died at 16 years of age with the same illness.
View Article and Find Full Text PDFAcute intermittent porphyria is an inborn error of metabolism characterized by the excretion of excess porphyrin precursors (porphobilinogen and usually delta-aminolevulinic acid) in the urine, and by sporadic attacks of neurologic dysfunction. The disease is complex, involving variable patterns of autonomic and peripheral neuropathy as well as the central nervous system manifestations. There may be alterations in carbohydrate, lipid, water, and electrolyte metabolism in addition to clinically inapparent endocrine abnormalities.
View Article and Find Full Text PDFTwo cases of relapsing juvenile chronic subdural hematoma with late relapse in adult life are presented and the literature reviewed. Both patients contracted subdural hematoma early in life; its persistence resulted in characteristic skull deformitites. The patients led an asymptomatic life until a second head trauma caused rebleeding into the old hematoma sac with recurring symptoms and signs.
View Article and Find Full Text PDFJ Neuropathol Exp Neurol
May 1975
Chronic experimental allergic encephalomyelitis (EAE), produced in inbred guinea pigs given a single inoculation during the juvenile period with isologous spinal cord in complete Freund's adjuvant, has been studied by light and electron microscopy. Most animals showed a delayed onset of nurologic signs from 12 to 68 weeks post-inoculation (PI), while several were asymptomatic up to 74 weeks PI. Two animals showed a relapsing clinical course.
View Article and Find Full Text PDFThe cerebro-hepato-renal syndrome is a rare familial malady with cerebral, renal, and skeletal abnormalities, severe hypotonia, cirrhosis, iron and lipid storage, and death within 6 months. Correlated electron microscopic, histochemical, and biochemical studies demonstrate defects in two oxidative organelles. Peroxisomes cannot be found in hepatocytes and renal proximal tubules.
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