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Biomedical subjects

M Deutsch

Publications and source records attributed to M Deutsch.

At least 109 records · Page 6Linked to original sources

Detection of melanoma by monitoring the intracellular fluorescein fluorescence polarization changes in lymphocytes.

The effectiveness of detecting melanoma by measuring the intracellular fluorescein fluorescent polarization (IFFP) of patients' SCM (structuredness of the cytoplasmic matrix)-responding lymphocytes was examined. SCM-responding lymphocytes from 46 melanoma patients and 32 healthy volunteers were labeled with fluorescein diacetate and challenged with different stimuli, and the resulting polarization was determined. The polarizations (P) obtained upon stimulation with nothing (P-0), encephalitogenic factor (P-EF), phytohaemagglutinin (P-PHA), or melanoma antigen (P-MEL), and the ratios RR(ef) (P-EF/P-PHA) and RR(mel) (P-MEL/P-PHA) were lower for SCM-responding lymphocytes from the patients as a group than for those of the controls. The specificity and sensitivity of the IFFP tests (using cutoff values) to detect melanoma were 90.6 and 73.9%, respectively. The IFFP tests may facilitate the discrimination between melanoma patients and healthy subjects, and may be used in follow-up of patients with melanoma.

Algorithms↗

Fourier analysis of differential light scattering for the quantitation of FSH response associated with structural changes in immortalized granulosa cells.

We have established granulosa cell lines which express constitutively the rat FSH receptors by cotransfection of primary granulosa cells obtained from preovulatory follicles with SV40 DNA, Ha-ras oncogene and a plasmid expressing FSH receptors. These cells respond specifically to ovine and human FSH by cell rounding, intracellular cAMP accumulation, and progesterone secretion in a dose-dependent manner. A new method for the demonstration and quantitation of changes in cell shape-Small Angle Laser Light Scattering (SALLS) analysis-has been utilized for measurement of cell rounding in response to FSH stimulation in these cells. When cells were incubated with increasing doses of either ovine or human FSH, partial rounding of cells was observed at FSH concentrations as low as 24 pM, while complete rounding of cells was observed at a range of 0.24-2.4 nM of FSH. Following aldehyde fixation, hormone-treated cells were examined using the method of SALLS analysis. Histograms obtained by applying SALLS analysis on FSH stimulated GFSHR-17 cells were a reflection of the structural changes induced by the hormone. FSH- and forskolin-incubated cells yielded structured distributions with defined mean size and standard deviations. Moreover, the increase in sharpness of dominant peak in the histogram was correlated with elevated concentration of FSH in a dose dependent manner. In conclusion, cellular response to FSH is correlated with a specific pattern of light scattered in immortalized granulosa cells expressing functional FSH receptors. Therefore, SALLS analysis may serve as a useful tool for in vitro bioassay of the gonadotropic hormone. Moreover, this method may lend itself to in vitro bioassay of any hormone that induces specific morphological changes in target cells.

Animals↗

Lymphocyte fluorescence polarization measurements with the cellscan system: application to the SCM cancer test.

The SCM (Structuredness of Cytoplasmic Matrix) cancer test, a procedure based on detection of differences in lymphocyte activation between individuals with and without cancer, has remained controversial with inconsistent results reported by different authors. As originally described, the test includes two technically demanding steps, the first a lymphocyte separation procedure and the second a series of fluorescence polarization measurements. The Cellscan, a high-precision static cytometer system has been configured to perform the SCM test. The apparatus facilitates the polarization measurements and can analyze cells separated using simpler procedures than were originally described. Using methods and diagnostic criteria adapted for the Cellscan system, the SCM test correctly classified > 90% of patients with cancer and > 90% of individuals without cancer.

Adult↗

Decrease of intracellular fluorescein fluorescence polarization (IFFP) in human peripheral blood lymphocytes undergoing stimulation with phytohaemagglutinin (PHA), concanavalin A (ConA), pokeweed mitogen (PWM) and anti-CD3 antibody.

In the present study we describe the induction of changes in intracellular fluorescein fluorescence polarization (IFFP) in lymphocytes undergoing activation with a variety of stimulants. These stimulants included the lectins phytohaemagglutinin (PHA), concanavalin (ConA), pokeweed mitogen (PWM) and anti-CD3 antibody. Changes in IFFP were detected in individual cells using the Cellscan apparatus. Our results show that by employing mitogenic concentrations of PHA, as revealed in a [3H]-thymidine incorporation assay, a decrease in the IFFP in human peripheral blood lymphocytes (PBL) occurred within 40 min. ConA and anti-CD3 affected similarly IFFP, whereas PWM, a B lymphocyte lectin, had no effect on IFFP at the concentrations employed. Kinetic analysis revealed that changes in IFFP occurred within 20-40 min after exposure to the stimulants and lasted for 24 h. Our results show that stimulants which activate CD3+ lymphocytes caused immediate changes in IFFP, in an enriched population of human PBL. The possible mechanisms involved in IFFP modulation following exposure to selected stimulants are discussed.

Antibody Specificity↗

Adaptation of the cellscan technique for the SCM test in breast cancer.

The value of the SCM (Structuredness of Cytoplasmic Matrix) cancer test, a procedure based on the detection of differences in lymphocyte activation in the presence and absence of cancer, has remained controversial, with inconsistent results having been reported among investigators. The Cellscan, a high-precision static cytometer system, has been designed to perform the SCM test; the apparatus facilitates the polarisation measurements and can examine cells which have been separated by simpler procedures than were originally described. In this study, using methods and diagnostic criteria adapted for the Cellscan system in a hospital environment, the SCM test correctly classified over 90% (76/80) of patients with breast cancer and differentiated over 90% (72/73) of individuals without cancer.

Adult↗

Immune thrombocytopenia and alpha-interferon therapy.

Thrombocytopenia is often found in patients with liver diseases, especially due to congestive splenomegaly caused by portal hypertension. Immune thrombocytopenia has been described rarely, and it seems to be especially associated with hepatitis C virus, which has been described as having a particular interaction with the immune system contributing to the induction of autoimmunity. Interferons, on the other hand, because of their immunomodulatory properties, are able to induce or exacerbate autoimmune diseases. Mild thrombocytopenia is a common adverse effect of interferon therapy. Severe life-threatening thrombocytopenia is extremely rare. We report two cases of severe immune thrombocytopenia in patients with chronic hepatitis C, probably induced by alpha-interferon. Bone marrow aspirate and elevated platelet-associated IgG antibodies, determined by indirect immunofluorescence, were suggestive of immune thrombocytopenia. None of the patients had any clinical sign of autoimmune syndrome, including arthritis, serositis, Sicca syndrome, vasculitis, thyroid abnormalities and others. Cryoglobulins and rheumatoid factor were tested and were undetectable. The patients' histories of exposure to alpha-interferon and the exclusion of other causes are most consistent with drug-induced immune thrombocytopenia. After alpha-interferon withdrawal, thrombocytopenia was treated successfully with prednisolone and immunoglobulins. Response to treatment was consistent with the diagnosis of alpha-interferon-induced immune thrombocytopenia and peripheral consumption of platelets.

Adult↗

Lumpectomy and breast irradiation for breast cancer after radiotherapy for lymphoma.

Six women received irradiation for lymphoma (Hodgkin's disease, n = 5; non-Hodgkin's disease, n = 1) to at least a mediastinal field (n = 2) or to a mantle field (n = 4), and subsequently developed breast cancer 10-27 years later. Three patients also received chemotherapy as a component of therapy for lymphoma. For breast cancer, all were treated with lumpectomy and breast irradiation to 5,000 cGy in 25 fractions plus a 1,000 cGy/5 fraction boost to the operative area using electrons. Two patients received adjuvant chemotherapy and three others tamoxifen for breast cancer. All women are alive and free of disease 15-118 months (median, 60 months) following breast irradiation. There have been no cases of significant acute reactions and no late sequelae such as skin pigmentation changes subcutaneous fibrosis, rib fractures, cardiac disease, or pulmonary fibrosis. The cosmetic result is considered good or excellent in all. Lumpectomy and breast irradiation is not contraindicated in the woman who develops breast cancer many years after irradiation of lymph node regions above the diaphragm for lymphoma.

Adult↗

Results of a prospective randomized trial comparing standard dose neuraxis irradiation (3,600 cGy/20) with reduced neuraxis irradiation (2,340 cGy/13) in patients with low-stage medulloblastoma. A Combined Children's Cancer Group-Pediatric Oncology Group Study.

PURPOSE: To determine in a prospective randomized trial the effect on survival, progression-free survival, and patterns of relapse of a decrease in the neuraxis radiation dose from 3,600 cGy in 20 fractions to 2,340 cGy in 13 fractions in patients with newly diagnosed medulloblastoma between 3 and 21 years of age with low T stage (T1, T2 and T3A), minimal postoperative residual tumor, and no evidence of dissemination (M0). METHODS AND MATERIALS: Between June 1986 and November 1990, the Children's Cancer Group and the Pediatric Oncology Group randomized 126 patients in a two-arm study comparing the two different doses of neuraxis irradiation. In both arms, the posterior fossa received 5,400 cGy in 30 fractions. All patients were staged with myelography, postoperative lumbar cerebrospinal fluid cytology, and postoperative contrast-enhanced cranial computerized tomography to ensure no evidence of dissemination and no more than 1.5 cm3 residual tumor volume. Overall survival, progression-free survival, and patterns of recurrence were carefully monitored. Prospective endocrine and psychometric studies were performed to determine the benefit of decreasing the neuraxis radiation dose. RESULTS: Following an interim analysis at a median time on study of 16 months, the study was closed, since a statistically significant increase was observed in the number of all relapses as well as isolated neuraxis relapses in patients randomized to the lower dose of neuraxis radiation. CONCLUSIONS: In patients with newly diagnosed medulloblastoma considered to have a good prognosis on the basis of low T stage, minimal residual tumor after at least subtotal resection, and no evidence of dissemination after thorough evaluation, there is an increased risk of early relapse associated with lowering the dose of neuraxis radiation from 3,600 cGy in 20 fractions to 2,340 cGy in 13 fractions.

Adolescent↗

Effect of interleukin-1 alpha, interleukin-1 beta and tumor necrosis factor-alpha on the intracellular fluorescein fluorescence polarization of human lung fibroblasts.

In the present study we aimed to detect early intracellular changes in the cytoplasmic matrix induced in human, pulmonary-derived fibroblasts following exposure to interleukin (IL)-1 alpha, IL-1 beta and tumor necrosis factor-alpha. Such changes were detected by measuring intracellular fluorescein fluorescence polarization (IFFP) using the Cellscan apparatus. IFFP measurement was selected in our study since it has been shown to reflect the microviscosity of the cytoplasmic matrix. Significant reductions (> or = 5%) in the IFFP were induced in fibroblasts by all the cytokines employed. The effect of cytokines on IFFP was achieved at concentrations of 5-10 ng/ml of the cytokines. The reduction in IFFP, following stimulation with the cytokines, was detected as early as 20 min after exposure to the cytokines, lasted at least 40-60 min after exposure to IL-1 alpha and IL-1 beta, and was inhibited by vinblastine, an inhibitor of the polymerization of microtubules. Our results show that IFFP measurements by the Cellscan may reveal rapid intracellular changes occurring in the cytoskeleton components of activated cells.

Cytochalasin B↗

Inhibition of mitogen-induced changes in intracellular fluorescein fluorescence polarization of human peripheral blood lymphocytes by colchicine, vinblastine and cytochalasin B.

We have previously reported that the exposure of human peripheral blood lymphocytes (PBL) to a variety of stimulants caused rapid changes in intracellular fluorescein fluorescence polarization (IFFP) in the activated cells. In the present study we further analyzed possible mechanisms responsible for the changes in IFFP in PBL exposed to phytohaemagglutinin (PHA) and anti-CD3 antibody. By employing several agents which are known to affect the polymerization of the cytoskeleton we showed that both cytochalasin B, which regulates the microfilaments structure, and vinblastine and colchicine, which affect the microtubules, completely abolished the changes induced in IFFP of human PBL by both PHA and anti-CD3. This effect was dose dependent and was noted at concentrations ranging from 10 to 100 microM of cytochalasin B and 10 microM of vinblastine and colchicine. The effect of these cytoskeleton modulators occurred within 20 minutes after the initiation of activation with PHA. Our results indicate that activation with PHA and anti-CD3 causes early changes in the microtubules and microfilaments components of the cytoskeleton. The possible application of IFFP measurement in analyzing early changes in the cytoskeleton following cell activation is discussed.

Colchicine↗

Indication that intracellular fluorescence polarization of T lymphocytes is cell cycle dependent.

The degree of depolarization of fluorescence light emitted from an organic dye, used as a molecular probe, is a powerful tool in probing the microenvironment. Polarization measurements of intracellular exogenous fluorescein have been shown to reflect the physiological state of the cells. The relationship between intracellular fluorescein fluorescence polarization (IFFP) and cell cycle, was investigated in the leukemia T-lymphocyte Jurkat cell line. Jurkat T cells were cultured in increasing cell densities, their cell cycle progression cytometrically monitored and the IFFP measured. At the highest cell density, the subpopulation of cells at the resting phases the (Gzero/G1) predominated, and the mean IFFP was 0.186 +/- 0.015. At the lowest density, with diminished proportion of cells in the G1/G2 stages the mean IFFP decreased to 0.126 +/- 0.01. Treatment of the Jurkat T cell line with phase arrested agents 1 microM hydroxyurea, or 1 microM nocodazole, arrests the cells in the S and G2/M phases, respectively. These treated cells exhibit significantly lower IFFP values, mean polarization value 0.140, as compared to 0.171 +/- 0.009 in control cells. Preincubation of Jurkat cells in buffer in accumulation of the cells in the Gzero/G1 phases as well as a parallel increase in IFFP. A characteristic decrease in IFFP was demonstrated upon triggering these cells with Phytohaemagglutinin (PHA). High correlation (Pearson correlation = 0.942) was found between percentage of cells in the Gzero/G1 phases and the mean IFFP of the measured cell population. These results may indicate that the intracellular microviscosity of Jurkat T cells as measured by IFFP, is changing over the cell cycle.

Cell Cycle↗