Chemotaxis of endothelial cells to formyl-methionyl-leucyl-phenylalanine.
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Animals↗
Biomedical subjects
T C Wright
Publications and source records attributed to T C Wright.
Effects of urea treatment on the divalent cation-independent cell aggregation of 3T3MIT fibroblasts.
Growth of nontransformed 3T3MIT fibroblasts in media containing 200 mM urea leads to the rapid acquisition of the transformed adhesive phenotype as evidenced by an increased rate of divalent cation-independent cell aggregation. The increased rate of divalent cation-independent cell aggregation of urea treated 3T3MIT cells shares many properties with the high rate of aggregation of transformed cells including a sensitivity to treatment with trypsin or hyaluronidase and a reduction in the presence of exogenously added hyaluronic acid. Reversal of the urea-induced increase in aggregation occurs within 24 hours in the absence of urea and can be blocked by 0.2 micrograms/ml cycloheximide. In the presence of cycloheximide, low rates of aggregation can be restored by the addition of urea-conditioned supernatents. The results of these experiments suggest that the loss of an aggregation-inhibitory activity during growth in media containing 200 mM urea is responsible for the increased rate of divalent cation-independent cell aggregation. After removal of this aggregation-inhibitory activity, the normally lowly adhesive 3T3MIT cells become phenotypically transformed with regards to the rate of divalent cation-independent cell aggregation.
Animals↗
A large functioning parathyroid lipoadenoma found in the posterior mediastinum.
A patient who was evaluated for a voice change was found to have a large posterior mediastinal mass on chest roentgenogram. Laboratory parameters suggested hyperparathyroidism. The 190-g resected tumor had the histologic features of a parathyroid lipoadenoma, that is, a diffuse mixture of parathyroid glandular elements and fat or myxoid stroma throughout. This case report emphasizes that the large size of these rare tumors may result in herniation into unusual sites, and this gives rise to a confusing clinical presentation. Ultrastructural analysis showed a uniform population of chief cells with a distribution of cellular organelles consistent with slow hormone production and release. Similarities to normal and adenomatous chief cells are discussed. The myxoid stroma surrounding the glandular elements had the ultrastructural features of loose connective tissue.
Adenoma↗
Differentiation of recurrent pulmonary emboli from chronic obstructive lung disease as a cause of cor pulmonale.
A patient with chronic obstructive pulmonary disease had severe dyspnea and cor pulmonale that were suspected in life and proved at autopsy to be the result of multiple small pulmonary thromboemboli. Radionuclide lung scanning and pulmonary angiography failed to diagnose the extensive peripheral embolization in this setting. The sensitivity and specificity of these diagnostic techniques are discussed, as well as the pulmonary function and gas exchange characteristics that led to the clinical suspicion of recurrent small emboli in this patient.
Autopsy↗
Divalent cation-independent aggregation of rat-1 fibroblasts infected with a temperature-sensitive mutant of Rous sarcoma virus.
Rat-1 fibroblasts infected with the temperature-sensitive transformation mutant LA 24 of Rous sarcoma virus have a high rate of divalent cation-independent homotypic cell aggregation when grown at the permissive temperature, 34 degrees. Cells grown at the nonpermissive temperature, 39 degrees, have a low rate of homotypic cell aggregation. Hyaluronic acid is involved in the homotypic aggregation of permissively grown cells since aggregation is blocked by either treatment of the cells with hyaluronidase or the presence of exogenously added hyaluronic acid. Despite their low rate of homotypic aggregation, nonpermissively grown cell are capable of heterotypically adhering to premissively grown cells. The formation of heterotypic aggregates is blocked by treatment of the nonpermissively grown cells with hyaluronidase but not by treatment of permissively grown cells with hyaluronidase. These results provide evidence that the divalent cation-independent aggregation of Rat-1 LA 24 cells is mediated by interactions between hyaluronic acid and other adhesive components on the cell surface.
Animals↗
The role of negative charge in spontaneous aggregation of transformed and untransformed cell lines.
No correlation between net negative surface charge as determined by electrophoretic light-scattering techniques and the rates of spontaneous aggregation of 3T3MIT and SVPy 3T3MIT cells has been found. Neuraminidase treatment of both 3T3MIT cells and SVPy 3T3MIT cells causes a significant decrease in electrophoretic mobility but only the 3T3MIT cells show an increase in spontaneous aggregation. An increase in spontaneous aggregation of 3T3MIT cells is seen after growth in 200 mM urea for 18 h but no change in net surface charge occurs. The distribution of anionic sites on the membranes of cells was determined using the ultrastructural marker polycationized ferritin. The distribution of polycationized ferritin-binding sites was essentially identical for both cell lines under all conditions when they were labelled at 4 degrees C. When the cells were labelled with polycationized ferritin at 37 degrees C it was found that cells which have a high net rate of spontaneous aggregation also show rearrangement of anionic sites on their surface membrane. Clustering and rearrangement of anionic sites at 37 degrees C correlate with high rates of spontaneous aggregation.
Animals↗
Relationships between cell-substratum interactions and the distribution of concanavalin A receptors of mouse embryo fibroblasts.
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Actins↗
Relation of lectin-induced and spontaneous adhesion to tumorigenicity.
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Animals↗
Rates of aggregation, loss of anchorage dependence, and tumorigenicity of cultured cells.
The net rate of spontaneous aggregation of cells suspended with EDTA was measured for various cell types including spontaneous transformants and cells transformed with DNA and RNA viruses. The anchorage dependence as determined by growth in methyl cellulose and the tumorigenicity in vivo were also determined. All cells that had lost their anchorage dependency and were tumorigenic showed a high net rate of spontaneous adhesion. A31 was the only nontransformed cell line to have a high net rate of adhesion. The net rate of spontaneous aggregation of cells is a quick and reliable index of tumorigenicity and offers a new approach to understanding the mechanisms of cell surface changes associated with transformation.
Cell Adhesion↗
Molecular variants of human papillomavirus type 16 and risk for cervical neoplasia in South Africa.
Non-European variants of human papillomavirus (HPV) type 16 are generally associated with a greater risk of cervical neoplasia than European prototype variants. We investigated whether this association would persist in a population in which non-European HPV 16 variants were more common. We sequenced HPV 16 isolates in cervical samples collected from 93 Black South African women enrolled in a cervical cancer screening study and examined associations between cervical neoplasia identified though colposcopy with cervical biopsy and the specific HPV 16 variant identified. The European prototype variant (EP) was the most commonly identified variant in this population (47% of all isolates), but African variants (Af-1 and Af-2) were also quite common (41% of all isolates). In contrast to previous studies, we found no evidence that non-European variants were associated with an increased risk of neoplasia. Rather, most of the HPV 16-associated cancers were found in association with EP (71% of 14 cases). In this setting where African HPV 16 variants were common, no increased risk for cervical neoplasia was found among women with these variants compared with other HPV 16 variants.
Adult↗
Cervical cancer screening, screening errors and reporting.
Screening for cervical carcinoma by cervicovaginal cytology has led to a marked reduction in the incidence of and mortality from this tumor over the last 50 years in essentially all countries with a functioning screening program. It is the most successful cancer prevention program of all times. Consequently, approximately 80% of the current incidence of and mortality from this disease occurs in geographic areas of underserved and underscreened women. Essential components of a successful program are a high coverage rate of the female population, screening at regular intervals, well-trained clinical and laboratory staff, and an efficient follow-up and treatment system. Deficiencies in any of these areas may lead to a failing screening system. Thus, the most important reason for the remaining mortality from cervical carcinoma in developed countries is lack of complete coverage. It is questionable if new and more expensive technologies will be able to renmedy the remaining failures of the system if no improvement in the coverage rate is achieved. Screening errors do occur but represent only a small fraction of screening failures. Currently, there are a number of terminology systems around the world; thus, a unified terminology is currently not a realistic goal.
Adult↗
Conventional cervical cytologic smears vs. ThinPrep smears. A paired comparison study on cervical cytology.
OBJECTIVE: To compare the time required for evaluation, the diagnostic accuracy and quality of conventional glass slide smears vs. ThinPrep smears in 365 women. STUDY DESIGN: Both smears were obtained at the same time using the Accellon Combi cervical biosampler. Histology served as the diagnostic "gold standard." RESULTS: The average screening time was 1 minute, 23 seconds, shorter per smear with the ThinPrep method as compared to the conventional glass slide (P < .001). Direct diagnostic agreement between the two smear methods was obtained in 311 of 364 evaluable smears (85.4%, kappa = .63). Despite the relatively high rate of "adequate but limited by absence of transformation zone components" observed with the ThinPrep method, the sensitivity and specificity of the ThinPrep method was slightly greater but not statistically significantly different than the conventional technique, irrespective of the disease categories (low and high grade squamous intraepithelial lesion and invasive cancer). CONCLUSION: The shorter time required to screen ThinPrep smears compared to conventional smears in this study was not sufficiently important to offset the current unit price for preparing ThinPrep smears.
Adenocarcinoma↗
Human immunodeficiency virus infection of early passage cervical epithelial cultures.
Women are infected with HIV in increasing numbers; the predominant mode of spread is through heterosexual transmission. Little is known regarding the mechanism of HIV transit through the female genital tract. We investigated whether early passage cervical epithelial cells could be directly infected with HIV-1LAI. Virus production was measured using the reverse transcriptase (RT) assay and direct assay for syncytia-forming units. In-situ hybridization was performed on infected cervical cell cultures. Immunostaining was carried out using a monoclonal antibody to leukocyte common antigen (LCA). Virus was recovered in the supernatants of all infected cervical cultures. Localization of HIV infection using in-situ hybridization identified rare cells in the population which gave a strong signal. These infected cells had a lymphoid morphology and were also detected using immunostaining for LAC. Cervical epithelial cells were uninfected in this in vitro model; cells in this population which supported viral replication were most likely of the macrophage/monocyte lineage.
Cells, Cultured↗