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Biomedical subjects

C E Bell

Publications and source records attributed to C E Bell.

At least 37 records · Page 2Linked to original sources

Comparative response of rainbow trout and rat to the liver mitogen, lead.

Lead nitrate and acetate are potent liver mitogens in the Wistar rat. Prior exposure to these agents has been found to alter their susceptibility to hepatotoxins. The present study assessed the capacity of both lead compounds to cause mitogenicity in the liver of adult male and female rainbow trout. Groups treated with a single intravenous or intraperitoneal injection of lead nitrate or lead acetate exhibited no statistically significant (P < 0.05) alterations in liver/body weight ratio nor hepatic DNA content. Results provide evidence of significant interspecies variation in the mitogenic response of rainbow trout and Wistar rats to the mitogenic potential of lead in the liver.

Animals↗

A comparative analysis of the health beliefs of older black males and females.

The purpose of this study was to examine differences in the health beliefs of older Black males and females. The sample consisted of 66 respondents, 39 females and 27 males. The six variables measured in this study were current health perceptions, health concerns, resistance-susceptibility perceptions, health outlook and rejection of the sick role. The Health Perceptions Questionnaire (HPQ) developed by Ware (1976) and a demographic profile were utilized to collect data. The HPQ is a self administered instrument, consisting of 32 questions which are designed to obtain information relative to an individual's beliefs about various aspects of his/her health status. Internal consistency coefficients of the HPQ ranged from 0.70 to 0.92. Descriptive statistics were utilized to describe the sample. One-way analysis of variance was utilized to test each hypothesis. Results revealed rejection of all six hypotheses at p < 0.05 level.

Black or African American↗

Monoclonal antibodies to human neuron-specific enolase reveal heterogeneity of the enzyme in neurons of the central nervous system.

Three monoclonal antibodies to human neuron-specific enolase (NSE) were used to survey the human brain and spinal cord for immunoreactivity. Two of the antibodies (EB and CF) recognized the same population of cells and cell processes. Reactivity was restricted to myelinated axons, basket cell bodies and processes, and a small population of pyramidal cell bodies in the visual cortex. The third antibody (AD) reacted with some, but not all, of the neuronal cell bodies in cerebral cortex, hippocampus, midbrain, and spinal cord. Many neurons did not react with any of the antibodies. The epitope recognized by AD was trypsin-sensitive, while those recognized by EB and CF were not. These studies suggest that NSE may have multiple conformational or structural forms which are segregated between the cell body and axon.

Animals↗

Serum levels of CA-125 in patients with endometriosis: a preliminary report.

Seven out of 8 patients with endometriosis demonstrated levels of CA-125 antigen above 35 U/ml. None of 15 patients with other benign gynecologic diagnoses demonstrated elevated levels. This antigen has been proposed as a tumor marker for epithelial carcinoma and other gynecologic neoplasms. However, it cannot be used to differentiate clinically between cancer and endometriosis.

Adolescent↗

Thrombomodulin, an endothelial anticoagulant protein, is absent from the human brain.

Protein C activation by thrombin is significantly accelerated by the endothelial cell cofactor, thrombomodulin. In this study, we have developed a radioimmunoassay for thrombomodulin and have measured the cofactor content in several human tissues. The assay method detects as little as 2 ng of thrombomodulin. The highest thrombomodulin content was found in lung and placenta, but the antigen was also detected in spleen, pancreas, liver, kidney, skin, heart, and aorta. Unexpectedly, thrombomodulin was absent from brain. Extracts from cerebral cortex, cerebellum, centrum semiovale, midbrain, basal ganglia, pons, and medulla were devoid of thrombomodulin. In contrast, thrombomodulin antigen is present in extracerebral intracranial vessels, including basilar and internal carotid arteries and choroid plexus, as well as in endothelium of the pia-arachnoid.

Brain↗

Acute intravascular hemolytic anemia in the black rhinoceros: hematologic and immunohematologic observations.

To investigate the syndrome of acute intravascular hemolytic anemia in the black rhinoceros (Diceros bicornis), laboratory techniques used in the differential diagnosis of hemolytic anemias were performed on blood samples from 6 black rhinoceroses: 3 nonrelated healthy rhinoceroses, 1 rhinoceros with iron deficiency anemia, and 2 rhinoceroses with intravascular hemolysis. Osmotic fragility, erythrocyte membrane protein composition, hemoglobin electrophoresis, and hemoglobin stability did not distinguish between healthy and affected (anemia or hemolysis) rhinoceroses. Polyclonal antiglobulin reagents were prepared in rabbits, using whole rhinoceros serum and purified rhinoceros immunoglobulin G. These reagents were nonreactive against erythrocytes of the healthy and iron-deficient rhinoceroses. Reactions with RBC from the rhinoceros with fatal hemolytic anemia indicated increased membrane coating by the third component of complement; this was not evident in a second rhinoceros that survived a hemolytic event.

Anemia, Hemolytic↗

Thrombomodulin is found on endothelium of arteries, veins, capillaries, and lymphatics, and on syncytiotrophoblast of human placenta.

We have used antibodies to human thrombomodulin isolated from placenta to investigate the distribution of this cofactor for protein C activation in human tissues. Thrombomodulin was found on endothelial cells of arteries, veins, capillaries, and lymphatics by immunocytochemical staining using an avidin-biotin peroxidase method. Thrombomodulin was not detected on sinusoidal lining cells of liver or on postcapillary high-endothelial venules of lymph node, although the latter contained another endothelial antigen, von Willebrand factor. Other cells noted to contain thrombomodulin antigen are those of the syncytiotrophoblast in placenta. The thrombomodulin in syncytiotrophoblast was primarily on the plasma membrane surface that forms the maternal blood sinus. Syncytiotrophoblast also stained with antibodies to von Willebrand factor, which implies that these cells have multiple endothelial functions. Thrombomodulin antigen was found in all organs studied, with the notable exception of brain.

Animals↗

Preparation and characterization of monoclonal antibodies to human neuron-specific enolase.

Neuron-specific enolase (NSE) has been increasingly recognized as a marker for neuroendocrine tumors including small cell carcinoma of the lung (SCCL). To prepare monoclonal antibodies (MAbs) specific for human NSE, we first developed a simple method of purifying NSE by direct chromatofocusing of a crude extract of human brain tissue. BALB/c mice were then immunized with our preparation of NSE, and MAbs against NSE were generated utilizing a hybridoma technique. The antibodies were screened against both NSE and non-neuronal enolase (NNE) by a solid-phase radioimmunoassay (SPRIA). After cloning and subcloning of hybridomas, two groups of anti-NSE MAbs were identified by SPRIA. One group reacted specifically with NSE but not with its isoenzyme NNE, irrespective of whether antigens were glutaraldehyde fixed or unfixed. A second group reacted with both NSE and NNE when the latter were glutaraldehyde fixed, but surprisingly with neither antigen in the absence of fixation. Group I antibodies were further characterized by immunoblotting, and by immunocytochemistry of normal brain and liver sections and sections of SCCL. The results further supported the specificity of group I antibodies for NSE. These MAbs have potential utility in the diagnosis and management of neuroendocrine tumors, and in further understanding the biology of NSE.

Antibodies, Monoclonal↗

Intestinal pseudo-obstruction as the presenting manifestation of small-cell carcinoma of the lung. A paraneoplastic neuropathy of the gastrointestinal tract.

A 58-year-old woman who had presented with intestinal pseudo-obstruction died 9 months later from rapidly progressive neurologic symptoms and autonomic insufficiency. Her gastric emptying had been markedly delayed and transit of markers had been slowed throughout the small bowel. A 5-hour manometric recording of the antrum and duodenum had shown absence of the normal interdigestive motor complex, which was replaced by irregular contractile activity of reduced amplitude. A small-cell carcinoma of the lung was found at autopsy. Pathologic study of the gut showed widespread degeneration of the myenteric plexus, which was infiltrated by plasma cells and lymphocytes and contained significantly reduced numbers of neurons. The extra-intestinal nervous system had neuronal loss and lymphocytic infiltrates in dorsal root ganglia. Thus, a gastrointestinal neuropathy causing intestinal pseudo-obstruction may be the presenting manifestation of a paraneoplastic syndrome associated with small-cell carcinoma.

Autonomic Nervous System Diseases↗

Pulmonary oat cell carcinomas. Expression of plasma membrane antigen correlated with presence of cytoplasmic neurosecretory granules.

A plasma membrane antigen highly associated with pulmonary oat cell carcinoma has recently been identified. Expression of this surface antigen was now examined in routine surgical pathology material from 32 primary lung tumors by immunostaining. The staining patterns of 17 tumors diagnosed as oat cell carcinoma by light microscopy were compared to those of 10 epidermoid carcinomas, four carcinoid tumors, and one lymphocytic lymphoma. In addition, when available, the oat cell carcinoma group was also studied by electron microscopy for demonstration of cytoplasmic neurosecretory granules. Twelve of the 17 oat cell carcinomas and one of the epidermoid carcinomas expressed the antigen. In this group of small cell tumors of the lung, aggrement was found between the expression of this immunochemical marker and the presence of neurosecretory granules in the cytoplasm of the tumors. Demonstration of this surface antigen in routine surgical pathologic material may be a useful aid in the diagnosis of these tumors. The failure of a group of tumors, which satisfied the light microscopic criteria for oat cell carcinoma to stain for the antigen, demonstrates heterogeneity within the oat cell carcinoma group.

Antigens, Neoplasm↗

Receptor-mediated uptake of lysosomal enzymes.

This paper reviews the evidence for two different forms of carbohydrate-mediated recognition of lysosomal enzymes by cell surface receptors. The recognition marker on lysosomal enzymes which are rapidly pinocytosed by fibroblasts contains phosphate, probably linked to D-mannose as a phosphomannosyl moiety. The fraction of lysosomal hydrolases bearing this recognition marker for fibroblasts varies, depending on the tissue source. Another form of recognition accounts for rapid plasma clearance of infused lysosomal enzymes in the rat. This rapid clearance is mediated by receptors on Kupffer cells and other reticuloendothelial cells that recognize mannosyl residues on the glycoprotein hydrolases.

Animals↗