Biomedical subjects
Publications and source records attributed to B H Liwnicz.
The association between vasculopathy and radiation is well recognized. Generalized arterial disruption and subsequent stenosis and occlusion is most often described. Additional vascular phenomenon, such as pseudoaneurysm formation, aneurysmal dilatation and aneurysmal rupture, are less common. We document a case of a cerebral aneurysm formation and rupture in the field radiated for cerebral neoplasm.
Peptide YY (PYY), a homolog of pancreatic polypeptide, has been shown to be released after stimulation of colonic mucosa with bile and fatty acids. In this study proximal jejunal and biliary involvement in the regulation of circulating PYY and the distribution of PYY-containing cells in rat intestine was evaluated. Six rats underwent proximal jejunal bypass, six rats had Roux-en-Y cholangiojejunostomies, and six sham-operated rats were used as controls. Three months after surgery feeding studies using either a mixed meal or a pure fat meal were performed in unanesthetized animals and venous blood was collected for plasma PYY radioimmunoassays. After the feeding studies, fresh specimens were taken from multiple areas of the intestine for immunohistochemical analysis. The surgical procedures did not significantly affect basal PYY plasma levels. Both mixed and fat meals significantly increased circulating PYY in control animals. Exclusion of the proximal jejunum resulted in inhibition of postprandial PYY release. The PYY response in rats with Roux-en-Y cholangiojejunostomies was blunted after a mixed meal and delayed after a fat meal. The incidence of PYY-containing cells increased along the functional gut in all rats. The bypassed jejunum in both experimental groups of animals contained fewer PYY-staining cells than sham-operated rats. Our results suggest that the exclusion of a segment of proximal jejunum from gastrointestinal continuity in rats leads to an inhibition of postprandial PYY release. PYY release may be controlled in part by stimulatory neural and/or endocrine signals originating from the proximal jejunum.
Complex partial seizures are associated with alterations in regional cerebral blood flow in abnormally spiking foci, as shown by positron emission tomography and single photon emission computed tomography, with an increase in flow ictally and a decrease interictally. Alterations of vasoregulation during ictal periods have also been described in animal seizure models. An electron microscopic study on human brain tissue from seven patients undergoing resections for the treatment of intractable complex partial seizures was performed to examine ultrastructural changes of the microvasculature and their locations within the microvessel wall. Biopsies were obtained intraoperatively from temporal lobe regions with electrocorticographically detected abnormal spiking and from regions without abnormality on electrocorticograms (control samples) removed as part of the therapeutic resection. A total of 539 microvessels from three regions were evaluated: spiking mesial temporal lobe, spiking lateral temporal cortex, and nonspiking (control) cortex. Evidence of pericyte degeneration (aggregates of cellular debris within the basement membrane) was noted in the majority of spiking area microvessels (76.7% in spiking mesial temporal cortex; 69.8% in spiking lateral temporal cortex) as compared with 37.8% of control microvessels (P less than 0.0005). Morphometric studies revealed a significant increase in total wall thickness, pericyte-basement membrane unit thickness, pericyte cytoplasmic density, basement membrane density, and basement membrane thickness in microvessels from spiking (mesial and lateral temporal cortex), as compared to control areas (P less than 0.01). No statistically significant difference was noted in pericyte coverage or pericyte or endothelial mitochondrial densities between microvessels in spiking and control regions. This study shows degeneration of pericytes, cells thought to play an essential role in microvascular hemodynamics, and thickening of microvessel walls in abnormally spiking brain regions in patients with intractable complex partial seizures. The pericyte degeneration and basement membrane thickening in abnormally spiking areas may explain alterations in vasoregulation, by a decrease in the microvascular compliance and in cross-capillary diffusion.
Astrocytes comprise about 25% of the cellular volume of the brain, and their main function is to maintain homeostasis of the neuronal environment. These cells are commonly identified on the basis of their membrane electrical properties and the presence of specific proteins. We have characterized the human astrocytoma cell line designated UC-11MG and have shown these cells have many of the traits of differentiated astrocytes. Many of the UC-11MG cells have a large resting membrane potential, averaging -74 mV. The slope of the Em vs log [K]o cuve was 58.5 mV per decade [K]o. The cells were inexcitable when exposed to brief depolarizing current pulses. The astrocytoma traits are virtually identical to those previously reported for normal astrocytes. The astrocytoma cells also express glutamine synthetase activity which is considered specific to astrocytes among brain cells. Previous work had also demonstrated the presence of other astrocyte markers glial fibrillary acidic protein and S-100 protein in the UC-11MG cells. The steady-state ion transport properties of Na+, Cl-, and K+ were also characterized in these cells, and the rates of efflux were found to be similar to those in other astrocytes, with the major difference being the presence of a second kinetic compartment in the UC-11MG cells. From this work, we conclude that the UC-11MG cell line displays prominent features associated with differentiated astrocytes, and may provide an excellent model system for the study of human astrocytes.
A 48-year-old man was admitted with the sudden onset of symptoms of stroke caused by hemorrhage in an oligodendroglioma. Despite surgery and antiedema treatment, the patient died. Histological evaluation revealed an oligodendroglioma with calcified capillaries of the retiform type. To further investigate this phenomenon, a total of 160 gliomas were reviewed: 90 glioblastomas multiforme, 30 oligodendrogliomas, and 40 astrocytomas. Sufficient data were available for clinical evaluation in 100 cases. Of these, 5% (two oligodendrogliomas and three glioblastomas multiforme) were related to clinically significant hemorrhages. Of the remaining cases, microhemorrhages were found in 53.0% of the glioblastomas, in 56.7% of the oligodendrogliomas, and in 10.0% of the astrocytomas. In each case reviewed, the capillaries were assigned to one of three groups: axial, retiform, or glomeruloid. Statistical analysis revealed a significant association between hemorrhages and retiform capillaries in all three types of tumors, except that in oligodendrogliomas the statistical significance held true when calcification of the capillaries was also present. Glomeruloid-type capillaries were only weakly associated with hemorrhages, and no association was found for axial capillaries. A large-scale prospective study is necessary to more precisely assess the role of each of the three types of capillaries in hemorrhages of gliomas. Based on data available so far, patients with glial tumors with retiform capillaries, confirmed on biopsy, should be carefully monitored to exclude possible intratumoral hemorrhage.
Two continuous human glioma-derived cell lines, UC-11MG and UC-302MG were established in our laboratory. Both cell lines persistently showed cytologic features similar to those of their respective original tumors. UC-11MG expressed glial fibrillary acidic protein (GFAP) and S-100 protein. The cell lines were negative for factor VIII related antigen (FVIII/RAg) and positive for fibronectin and neuronal specific enolase (NSE). Electron microscopic studies of UC-11MG revealed intermediate filament; filopodia and pinocytic vesicles were present in both lines. Dibutyryl cAMP (dB-cAMP) caused inhibition of growth and marked shift in the morphology of UC-302MG toward spindle cells. The cytologic appearance of UC-11MG treated with dB-cAMP was altered less, but cells showed a stronger GFAP expression, with 'cable' formation. Doubling time was 41.0 +/- 6.4 hours for UC-11MG and 43.7 +/- 6.6 hours for UC-302MG. The karyotypes of both cell lines were aneuploid with chromosomal derangement and markers characteristic for each line.
Serum from a patient with oat cell (OC) tumor and paraneoplastic upper and lower motoneuron syndrome showed binding of IgG but not IgM to normal human cerebral cortex (CC), molecular (M), and Purkinje (P) cell layers of the cerebellum, anterior horn cells (AHC), and dorsal root ganglia (DRG). There was no binding to glial and granular cells, white matter, peripheral nerve, or OC. Sera from three patients with OC tumor without neurologic deficit, three patients with non-OC lung cancer and peripheral neuropathy, and five healthy subjects were used as controls. While none of the control sera showed binding to the CC or M layer, the three controls with OC showed 50% reactivity with AHC, and other controls showed weak staining of PC, AHC, or DRG. Absorption of the patient's serum with cerebral or cerebellar tissue, but not with liver or spinal cord, resulted in elimination of the immunostaining. Staining of the CC and M layer could not be blocked by a monoclonal IgG to a glioma cell line, but partial blocking occurred by preincubating the tissue with monoclonal IgG (MF 491) to gastric carcinoma and cross-reacting with OC and several neural elements. The results suggest specific binding of the patient serum IgG to the CC and M layer; however, the relationship of this antibody to the pathogenesis of the paraneoplastic syndrome remains elusive.
Serum from a 60-year-old man with multiple myeloma (monoclonal IgA-lambda) and peripheral sensorimotor neuropathy showed immunohistochemical binding to normal human endoneurium in dilutions up to 1:6000 (IgA = 1 mg/dl). The binding was shown to be specific for IgA-lambda and it was negative for IgA-kappa, IgG and IgM. Absorption of the serum with peripheral myelin eliminated the myelin immunostaining. Peptic digestion of the serum failed to eliminate immunostaining of the endoneurium. Immunoblot analysis revealed reactivity of the monoclonal IgA with 58,000, 43,000 and 18,500 dalton components of human nerve endoneurium. Sera from two patients with monoclonal IgA without peripheral neuropathy, from one patient with peripheral neuropathy and lung cancer, from one patient with stroke and from six normal subjects failed to stain myelin in sections of peripheral nerves or to react in immunoblots at comparable serum concentrations. Axonal staining was seen with some of the control sera. The relationship of the findings to the pathogenesis of peripheral neuropathy in multiple myeloma is discussed.
Formalin-fixed, paraffin-embedded tissue sections of normal skin, sebaceous hyperplasia, nevus sebaceus, sebaceous adenoma, and sebaceous carcinoma were studied by means of biotinylated and FITC conjugated concanavalin A (Con A) and Lens culinaris agglutinin (LCA). At relatively high concentrations of these lectins, all cutaneous epithelial cells were stained. As the concentration of LCA was lowered, there was a corresponding decrease in the intensity of staining of all epithelial cells. With lowered concentrations of Con A, staining of sebaceous epithelium remained strongly positive, while staining of other epithelia decreased in a manner similar to that seen for LCA. These staining patterns were seen in normal and neoplastic tissues. Both Con A and LCA are known to bind to alpha-D-mannopyranosyl and alpha-D-glucopyranosyl residues of glycoproteins and glycolipids. The difference in staining of sebaceous epithelial cells by Con A and LCA suggests that the binding of these lectins is not determined strictly by the presence of alpha-D-mannopyranosyl or alpha-D-glucopyranosyl residues, but is modified by side-chain substitution on the monosaccharides and/or by the oligosaccharide which contains the particular monosaccharide. Whichever event is operative, a saccharide moiety is present on the surface of mature sebaceous cells which has a strong affinity for Con A.
The binding of the lectins concanavalin A (Con A), peanut lectin (PNL), Ricinus communis agglutinin I (RCA I), Ulex europaeus agglutinin I (UEA I) and wheat germ agglutinin (WGA) to rat brains at several fetal and neonatal stages of development was evaluated. Cytochemical staining was performed using biotinylated lectins with an avidin-biotin complex with and without neuraminidase digestion. Differential binding to ventricular and intermediate layers, cortical plate and blood capillaries was demonstrated at different stages of development. WGA bound to blood capillaries at all ages, RCA I and PNL + N (PNL after neuraminidase digestion) from gestational day 22 on. During migration RCA I bound to cell fibers, PNL and UEA I to migrating cell bodies. Con A and UEA I stained perikaryonal structures of cortical neurons increasingly during neonatal development. It appears that cytochemical methods utilizing lectins can be used for the investigation of developmental processes of the central nervous system.
Antineural antibodies have been described in sera of patients with neurodegenerative disorders. We looked for the presence of those antibodies in the sera of patients with spinocerebellar degeneration. Serum IgG from four patients with familial spinocerebellar degeneration showed strong binding to cerebral cortical neurons, Purkinje cells, and dorsal root ganglia of normal human tissue sections stained with the peroxidase antiperoxidase (PAP) method at serum dilution of 1:500. No binding to neuroglia cells or cells of the granular layer of the cerebellum was seen. Sera from four immediate, asymptomatic relatives (son or sibling) showed only moderate binding to Purkinje cells and to dorsal root ganglia, but not to cortical neurons. Sera from seven patients with neurological diseases other than spinocerebellar degeneration and from five healthy subjects showed no binding to neural elements. The findings may be of value in the diagnosis and screening of patients suspected of having spinocerebellar degeneration; however, the significance of these antineural antibodies in the pathogenesis of spinocerebellar degeneration is uncertain and awaits further studies.
A unique case of central nervous system metastases of mixed malignant mesenchymoma in an 84-year-old man is described. The tumor exhibited an osteogenic appearance in the cerebral lesion and a primitive mesenchymal appearance in lesions of the brain stem and cerebellum. The primary site was apparently the chest wall, and there were also metastases to the lung and liver.
The mitochondrial content of endothelial cells of cerebral cortical capillaries in patients with Alzheimer's disease and age-matched controls was calculated using stereologic methods. No morphologic abnormalities or quantitative changes in endothelial mitochondria are reported. Our findings do not support the hypothesis of a blood-brain barrier defect in Alzheimer's disease.
Four cases of radiation-associated gliomas are described. All patients were white men, irradiated in childhood for craniopharyngioma, anaplastic ependymoma, retinoblastoma of the orbit, and Burkitt's lymphoma, respectively. The dose ranged from 1800 to 5900 rads, and the latency period was 5 to 25 years. All primary and secondary tumors were verified histologically, and no evidence of persistence of the primary tumors was found. All secondary tumors arose in the fields of irradiation. Ninety-six cases of radiation-induced tumors of the central nervous system have been reported in the literature to date. Twenty-four were gliomas and occurred mainly in young men.
Cells of two human glioma lines (UC-35AG, UC-58EG), a human medulloblastoma line (UC-51MB), two rat glioma lines C6, RG2), and a rat schwannoma line (Lew-MS) were injected i.v. into male nude mice (BALB/c nu/nu). Each animal was injected with 10(6) viable cells of a particular line; for each line there was a group of eight to nine animals. The mice developed disseminated (metastatic) tumors from all lines. The incidence of mice developing metastatic tumors was different for the various lines: 2/8 for the UC-34AG, 7/9 for the UC-58EG, 1/8 for the UC-51MB, 7/8 for the C6 line, 8/8 for the RG2 and 1/9 for the Lew-MS line. The shortest survival of the mice with tumors was observed with C6 (all died on days 10-14 post injection), and with RG2 (all died from day 32 to day 39 following injection). With the remaining lines, all mice survived until they were killed on day 40 after injection. Most frequently the tumors developed in the lung. Other organs, e.g., kidney or liver, were sometimes also involved, but usually to a considerably lesser degree than the lung. Metastases never developed in the CNS. It was observed that tumors of certain glioma lines tended to grow in the lung in characteristic patterns and involved or spared other organs.
A case of subacute sclerosing panencephalitis (SSPE) in a 20-year-old male who died within 2 months, is described. Light microscopy revealed massive neuronal loss, reactive gliosis, perivascular cuffing and intranuclear (Cowdry type A) and intracytoplasmic inclusions. Immunocytochemical stain with the complement-fixing measles antibody was positive for intranuclear and intracytoplasmic inclusions. The reactive glia cells were positive for glial fibrillary acidic protein. Electron microscopy revealed a paramyxovirus-like structure of the nucleocapsids, occasionally showing a 'fuzzy' appearance in the cytoplasm. Crystal-like intracytoplasmic inclusions were also seen. The inclusions occurred in oligodendroglia cells, astrocytes and neurons. This case illustrates a rapidly progressive form of SSPE which, in some aspects, differs from the chronic form and resembles acute measles encephalitis.
We describe a case of a granular cell tumor (GCT) of the suprasellar region with an 11-year history in a 26-year-old woman. The computed tomographic scan showed a midline, contrast-enhancing, noncalcified mass. The biopsy was diagnosed as GCT. The tumor was treated with radiation therapy. At necropsy, a large, homogeneous GCT surrounded by gliosis was found. The tumor cells were filled with granules positive for periodic acid-Schiff, diastase-resistant. The cells did not contain glial fibrillary acidic protein or S-100 protein. Electron microscopy showed tumor cells filled with innumerable lysosomal structures. No intermediate filament was found within the cytoplasm. The tumor cells were not surrounded by a basement membrane. Based on this study and on our review of the literature, the suggestion that GCT has a multicellular origin is upheld.