Expression of CXCR4 in the brain of feline immunodeficiency virus infected cat.

Advances in understanding the mechanisms of human immunodeficiency virus (HIV)-1 entry have revealed that the cell surface CD4 expression alone is insufficient and needs an additional molecule on its surface for the viral entry. These are G-protein coupled seven transmembrane (7-TM) family molecules (chemokine receptor) and amongst them one is CXCR4. Feline homologue of CXCR4 acting as a co-receptor for feline immunodeficiency virus (FIV) entry is already reported for the Crandle feline kidney cells strain (CrFK) of FIV. An experiment was carried out to search the expression of CXCR4 retrospectively in FIV (CrFK) infected cat brain tissues using immunohistochemically in the formalin fixed paraffin sections against 12G5, a mouse monoclonal antibody to CXCR4. We observed the expression of this receptor in feline neurons, astrocytes and in some vascular endothelial cells. The study of expression of CXCR4 in the brain, which is one of the many chemokine receptors in the central nervous system, may provide further insight into the interactions between brain cells, pathogens, and the immune system, and help understand the pathogenesis of HIV dementia.

Blood glucose and ischemic brain damage.

The effect of hyperglycemia on ischemic brain damage was studied in a rat model of incomplete ischemia. Incomplete ischemia was produced by permanent occlusion of one (either left or right) common carotid artery (CCA). Hyperglycemia was induced by intraperitoneal injection of 50% glucose, and same volume of physiological saline was injected in the controls 40 min before CCA ligation. Serum glucose level, at the time of vessel ligation, was 33.3 mMol/L. After CCA ligation, the rats were allowed to wake up and survive for upto 1 month. Perfusion-fixed brains were embedded in paraffin, subserially sectioned, and stained with haematoxylin-eosin/cresyl violet. Brain from sham-operated animals showed no damage neurons. Only mild neuronal damage was observed in saline pre-treated rats in CA1 area. Histological examination 24 h after CCA occlusion revealed ischemic neuronal cell damage to be more extensive in hyperglycemic rats. Neuronal damage was found in the major brain structures vulnerable to several insults. Some of those damaged neurons recovered well, but presence of some damaged neurons at 1 month of recovery suggesting delayed recovery. The results indicate that increased blood glucose level (hyperglycemia) during brain ischemia exaggerates structural alterations and leads to delay in recovery.

Nephrogenic adenoma of the ureter--a case report.

We present a case of nephrogenic adenoma, a rare benign lesion arising from the ureter. Histologically, it showed the formation of epithelial lined tubules resembling the renal tubules. Special Stain demonstrated the presence of intraluminal PAS-positive materials.

Bauhinia purpurea and Pisum sativum lectin binding in human breast.

The binding of biotinylated bauhinia purpurea (BPA) and pisum Sativum (PSA) lectins to paraffin-embedded tissue sections from 10 normal breast and 55 breast carcinoma has been investigated by applying avidin biotin peroxidase method (ABC). BPA showed very low affinity for normal breast epithelium and the binding was confined to the luminal surface. Eighty-seven percent carcinoma bound BPA, and the staining patterns varied depending on the histologic grade of tumors: luminal surface binding in grade 1 carcinomas; diffuse, granular cytoplasmic with para- or perinuclear deposits and staining along the plasma membrane in grade 2 and grade 3 carcinomas. PSA bound consistently to the luminal surface of all ducts and acinar cells of normal breast tissue. PSA was reactive with all carcinoma but the staining profiles were similar regardless of the tumor differentiation. It is concluded that the lectins used in this study have limited usefulness in routine diagnosis.

Lectin histochemistry of normal lung and pulmonary carcinoma.

Normal bronchopulmonary tissues and pulmonary carcinomas including three major types (squamous cell carcinoma, adenocarcinoma, and small-cell carcinoma) were studied using three biotinylated lectins (Bauhinia purpurea [BPA], Phaseolus vulgaris [PHA], and Maclura pomifera [MPA]) by avidin biotin peroxidase complex (ABC) method. The study demonstrated that BPA binds with macrophages and pneumocytes of normal tissue, and with adenocarcinoma and small-cell carcinoma, but nonreactive with squamous cell carcinoma. PHA and MPA bound to all the normal components of bronchopulmonary tree and carcinomas of all types. Adenocarcinoma showed the highest density of reacting sites for BPA and MPA, and squamous cell carcinoma showed the highest binding sites for PHA, while small-cell carcinoma were the lowest reacting variant for all lectins. Lectins used in this study have limited usefulness for the diagnosis of pulmonary neoplasms.

Tumor marker studies of cervical smears: an immunohistochemical approach.

Immunoreactivity with monoclonal antibodies against epithelial membrane antigen (EMA), vimentin, squamous epithelium-specific keratin, nonsquamous epithelium-specific keratin, and polyclonal antibodies epithelial cells of 55 cervical smears using the avidin-biotin-peroxidase complex and indirect immunoperoxidase methods to detect antigens. Most of the abnormal squamous cells with few normal cells were reactive for EMA but the intensity of the reaction was variable in both cases. There was no correlation in the reactivity between normal and abnormal cells with different cytokeratins varying in their molecular weight. Vimentin was also reactive with both cells. The results of this experiment suggest that antibodies used, appear to be of limited usefulness in the diagnosis of cervical smears.

Bauhinia purpurea agglutinin (BPA) binding sites in human gastrointestinal tract.

The binding of biotinylated BPA to parraffin sections of 18 normal gastrointestinal tract mucosa, 5 nonneoplastic polyps (NNP), 12 adenomas, and 59 carcinomas was studied by using avidinbiotin peroxidase complex (ABC) technique. In normal mucosa BPA appeared to bind both mucus and nonmucus glycoproteins but goblet cell mucus showed a decrease in binding and increase in binding of nonmucus glycoproteins as the cells lose their differentiation. BPA showed characteristic binding patterns in adenoma and carcinoma that differed from the pattern in normal mucosa. In normal mucosa linear binding to the apical cytoplasm in the columnar cells of the surface epithelium was observed, whereas in adenomas and carcinomas, in addition to the linear binding to the apical cytoplasm, diffuse cytoplasmic and granular deposits in the supranuclear, paranuclear or infranuclear zones were seen. Our findings suggest that BPA binding patterns in normal and neoplastic mucosa are related to the degree of cellular differentiation. In the process of malignant transformation the carbohydrate distribution undergoes progressive changes through the adenoma carcinoma sequence. These changes are related to the degree of dysplasia in adenomas and to the degree of differentiation in carcinomas.