The progressive rise of mature CD5+ B lymphocytes, despite the low proportion of proliferating cells, has led to the notion that B cell chronic lymphocytic leukemia (B-CLL) is primarily related to defective apoptosis. The microenvironment likely plays a prominent role because the malignant cells progressively accumulate in vivo, whereas they rapidly undergo spontaneous apoptosis when cultured in vitro. To assess microenvironment-mediated survival signals, B-CLL cells were cultured with a murine fibroblast cell line, Ltk-, with and without an agonistic antibody to CD40.
View Article and Find Full Text PDFObjective: To investigate the association of the (CA)n dinucleotide repeat in the 3' untranslated region (3'UTR) of the CD154 gene with systemic lupus erythematosus (SLE), and its functional role in protein expression.
Methods: The allelic and genotypic distributions of the polymorphism were compared in 80 patients with SLE and 80 controls. A complete clinical and analytical database was recorded in each patient in order to correlate the clinical manifestations in SLE with different alleles.
Cytometry B Clin Cytom
November 2003
Background: Recent evidence indicates that the slowly expanding population of CD5(+) B cells that characterizes B-cell chronic lymphocytic leukemia (B-CLL) could be related to defects in the response to cytokine produced by T cells that regulate apoptosis. We studied the intracellular expressions of interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) in T-helper 1 cells (Th1 response) of B-CLL.
Methods: Peripheral blood mononuclear cells from 21 healthy individuals and purified T cells from 21 early-stage and 15 late-stage B-CLL patients were activated with phorbol myristate acetate and ionomycin.
Tuberculosis (Edinb)
June 2002
We assessed by flow-cytometry the Th1/Th2 profiles in peripheral blood lymphocytes (PBL) from patients with active tuberculosis (TB), before and after antituberculous therapy, and from healthy tuberculin-positive and -negative reactors. PBL from patients showed a reduced potential for Th1-cytokine (notably IFN- gamma) production after culture with a policlonal stimulus. When these PBL from patients were cultured with a M.
View Article and Find Full Text PDFOne hundred fifteen patients with 119 pulmonary lesions in which malignancy was suspected underwent a SPECT study with 99mTc-Tetrofosmin (TTF) to assess the possible factors involved in the uptake of the radiopharmaceutical. The TTF uptake rate in the lung tumor with respect to that of healthy tissue (TTF index) was evaluated in terms of: benignity and malignancy, histological type, stage, cell differentiation, size, necrosis, survival and the influence of P-glycoprotein (Pgp), detected by immunohistochemistry, on the TTF uptake. The mean TTF index in the 18 benign lesions studied was 1.
View Article and Find Full Text PDFThe CD154 gene contains a dinucleotide repeat (CA)n in the 3' untranslated region. Allelic distribution in Spanish populations from two areas with different genetic background, the Canary Islands and Peninsula, are described. Seven alleles with different allelic distribution between the two groups, were found.
View Article and Find Full Text PDFB-cell chronic lymphocytic leukemia (B-CLL) is characterized by the slow and progressive accumulation of monoclonal apparently mature, CD5(+) B lymphocytes. The majority of circulating cells appear to be nondividing, and it has been suggested that a prolonged life span is mainly responsible for the accumulation of the leukemic cells. However, spontaneous programmed cell death by apoptosis occurs when B chronic lymphocytic leukemia cells are cultured in vitro.
View Article and Find Full Text PDFBackground: Adrenomedullary chromaffin cells are neural crest derivatives widely used as a model system to study neurosecretory mechanisms. Morphological, immunohistochemical, and functional data indicate that chromaffin cells are heterogeneous and support the distinction between adrenaline (A)- and noradrenaline (NA)-producing and secreting cells. The aim of this study was to characterize by flow cytometry the two main chromaffin cell subtypes in suspensions of cultured bovine chromaffin cells.
View Article and Find Full Text PDFDNA ploidy and cell-cycle distribution were determined by flow cytometry in fresh tumor tissue of 27 epithelial head and neck carcinomas. Epithelial cells were labeled with a fluorescein-isothiocyanate-conjugated cytokeratin antibody to study the possible influence of contaminating stromal and inflammatory cells on the results of cell-cycle analysis of tumor cells. The patient sample included 26 men and 1 women with a mean age of 60 years.
View Article and Find Full Text PDFUnlabelled: We used thoracic SPECT to study the 99mTc-tetrofosmin (TF) uptake in patients with non-small-cell-lung-carcinoma (NSCLC). The results were compared with the percentage of P-glycoprotein (Pgp) found in flow cytometric analysis (FC) of samples of surgically-resected tumor tissue.
Material And Methods: A total of 21 patients with NSCLC were studied by means 99mTC-TF and thoracic SPECT.
The purpose of this study was to compare the physiological responses of professional and elite road cyclists during an incremental cycle ergometer test. Twenty-five elite cyclists (EC; 23+/-1 yr) and 25 professional cyclists (PC; 25+/-2yr) performed a ramp protocol (increases of 25 W x min(-1)) during which the following parameters were measured: oxygen consumption (VO2), pulmonary ventilation (VE), ventilatory equivalents for oxygen and carbon dioxide (VE x VO2(-1) and VE x VCO2(-1), respectively), respiratory exchange ratio (RER), ventilatory thresholds 1 and 2 (VT1 and VT2, respectively), blood lactate, and electromyographic activity (EMG) of the vastus lateralis. Significant differences existed between the two groups mainly at submaximal intensities, since both VT1 and VT2 occurred at a higher exercise intensity (p<0.
View Article and Find Full Text PDFArch Otolaryngol Head Neck Surg
August 1998
Background: For laryngeal carcinoma, the present TNM clinical staging system does not seem completely satisfactory as a guide for providing a prognosis for survival. We believe that natural killer cell activity would probably have a role in a more reliable system. Therefore, we analyzed the disease outcome with previously untreated epidermoid carcinoma of the larynx, evaluating classic clinical and pathologic factors, as well as natural killer cell activity in peripheral blood samples of the patients.
View Article and Find Full Text PDFWe investigated whether 2-chlorodexoyadenosine could induce apoptosis in B cell chronic lymphocytic leukemia (B-CLL) cells in vitro using clinically achievable drug doses, measuring apoptosis ratio by flow cytometry. B cells were isolated from previously untreated patients and apoptosis was measured in these cells immediately after isolation and following incubation in vitro, without and with 2-chlorodeoxyadenosine at different concentrations, for 24 and 48 h. Distribution of cellular DNA content and quantitative analysis of apoptosis were determined by standard propidium iodide staining and flow cytometry.
View Article and Find Full Text PDFArch Otolaryngol Head Neck Surg
July 1997
Background: Although there are a number of reports concerned with the role of immunity in the sudden onset of progressive sensorineural hearing loss, there are few references dealing with the involvement of immune-mediated mechanisms in sudden deafness.
Objectives: To study the phenotype of peripheral blood lymphocytes in a group of patients with sudden deafness by use of 3-color flow cytometry.
Design: The study was carried out prior to the start of steroid therapy.
We describe a 57-year-old woman who presented with a constitutional syndrome, glomerulonephritis, and lymphocytosis. The phenotypic study, using flow cytometry, showed an expansion of natural killer (NK) cells (CD2+, CD3-, CD16+, CD56+, and CD7+). We performed a functional study of peripheral blood mononuclear cells (PBMCs) and of purified CD16+ cells (NK cells) and CD3+ cells (normal T cells).
View Article and Find Full Text PDFActa Otorrinolaringol Esp
February 1996
The status of natural killer (NK) cell activity in peripheral blood, based on number and functional state, was studied in relation to the clinical and histopathologic stage of 52 patients with laryngeal carcinoma and in 23 healthy controls. The number of NK cells, estimated using CD16 and CD56 monoclonal antibodies, was similar in patients and controls and showed no relation to tumor size and nodal involvement. NK cell function did not show significant differences in spontaneous cytotoxic activity either overall or in relation to tumor size and the presence of palpable lymph nodes.
View Article and Find Full Text PDFPatients with pernicious anemia have an estimated risk of gastric adenocarcinoma that ranges from three- to fivefold greater than that of the general population. It has been reported that NK cells may be involved in immunosurveillance against tumor spread. The natural killer cell activity of peripheral blood mononuclear cells was analyzed in 22 patients with pernicious anemia and in 19 healthy controls.
View Article and Find Full Text PDFTo study the correlation between oncogenes and the cytotoxic effect of tamoxifen in estrogen negative (ER) cells, we transformed mouse keratinocyte and fibroblastic cell lines with several oncogenes and studied cell viability, thymidine incorporation and PKC levels. We show that v-myc and v-H-ras oncogenes increase sensitivity in both cell types and that Neu and mutant p53 also increase sensitivity to tamoxifen, more significantly in the epithelial cells. Conversely, transformation with adenovirus E1a oncogene induces resistance to tamoxifen in both cell types.
View Article and Find Full Text PDFThe functional response and phenotypic characterisation of peripheral blood T cells were studied in 41 patients with autoimmune gastritis--nine patients with autoimmune gastritis alone, 11 with untreated pernicious anaemia, and 21 with resolved pernicious anaemia who were taking vitamin B-12. Phenotypic analysis showed no changes in the CD4/CD8 ratio in any group of patients. CD3+ cells were significantly decreased and CD16+ cells were significantly increased in patients with autoimmune gastritis alone.
View Article and Find Full Text PDFWe studied the natural killer (NK) activity of peripheral blood mononuclear cells (PBMC) in patients with Graves' disease (GD). Peripheral blood mononuclear cells from 20 untreated hyperthyroid patients with GD showed a significantly reduced NK activity against 51 Cr-labeled K562 cells (33.9 +/- 15.
View Article and Find Full Text PDFResponse to chemotherapeutic agents in malignant tumors depends on many factors, most of which are as yet unknown. We investigated the correlation between the activation of different oncogenes and protein-kinase-C (PKC) modulation, and the cytotoxicity of some of the most widely used anti-cancer drugs. We transformed the murine keratinocyte cell line PAM 212, with different oncogenes (v-H-ras, v-myc and adenovirus E1a) and a mutant p53 suppressor gene (mp53).
View Article and Find Full Text PDFActa Otolaryngol
November 1994
We studied the functional response and phenotypic characterization of peripheral blood T cells and their correlation with the clinical stage of disease in 29 males with previously untreated carcinoma of the larynx and 24 healthy male controls. Peripheral blood T cells, phenotypically CD2+ CD3+, were significantly decreased in the patients relative to the controls. Patients with advanced locoregional extension (T4 and N1, 2, 3) also showed a diminution of the CD4+ subpopulation of T cells.
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