The effectiveness of detecting melanoma by measuring the intracellular fluorescein fluorescent po... more 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.
Advances in Experimental Medicine and Biology, 1984
Attention is drawn to experimental results from many laboratories which indicate that the isometr... more Attention is drawn to experimental results from many laboratories which indicate that the isometric force (F) in the contraction of striated muscle fibers is linearly proportional to their variable cross-section area (A). Reversible swelling of intact, skinned, or glycinerated fibers can be induced by changes in tonicity, ionic strength or pH. In all cases where careful measurements of F and A are reported, the maximal isometric tension namely, T = F/A, is found around 1 kgf /cm2, even though F and A may change more than threefold for a given fiber at a certain length. These results seem to be independent of the fiber length or temperature. Thus, the isometric tension T in striated muscle does not depend on the number or the rate of the interacting cross-bridges. This result of constant isometric tension, which has so far received little attention, is however, a simple prediction of the hydraulic mechanism which is proposed for muscle contraction. Therefore, the hydraulic model, which is based on the hypothesis of vectorial flux of energetic protons deserves serious consideration.
Advances in Experimental Medicine and Biology, 1986
The mechanism whereby fixation of the membrane attack complex of complement (C') induces irre... more The mechanism whereby fixation of the membrane attack complex of complement (C') induces irreversible membrane damage ultimately leading to cell death may not be an exclusive membrane event. We investigated possible involvement of cellular metabolism in the lysis of nucleated cells induced 3by antibody (Ab) against cell surface antigens and C'. Using 31P-NMR spectroscopy we observed a marked reduction of creatine phosphate and relatively unaltered ATP levels shortly after the application of C', but prior to the onset of lysis. These metabolic changes preceded uptake of vital stairlT (e.g., eosine), or release of isotopically [\left( N{{a}_{2}}^{51}Cr{{O}_{4}} \right)\] -labeled cytoplasmic components. Monitoring the course of natural cell death over a 6-hr period revealed a comparable depletion of creatine phosphate prior to cell death. We would like to propose that membrane fixation of the C' attack complex induce metabolic depletion of high energy components which in turn cause irreversible cell swelling and membrane damage leading to cytolysis.
We analysed a series of 81 colorectal cancer cases in which the SCM (structuredness of the cytopl... more We analysed a series of 81 colorectal cancer cases in which the SCM (structuredness of the cytoplasmic matrix) test had already been performed with a diagnostic sensitivity of 92% and a specificity of 92.6%, yielding positive and negative predictive values of 96.3% and 84.7% respectively. We subdivided this group of 81 patients by anatomic location of the malignancy. Although the resultant subgroups were admittedly small, we noted a tendency for the most prominent changes in observed and calculated polarization parameters to be associated with cecal cancers. This finding was of special interest because the cecum is the most inaccessible site for colonoscopy. Ongoing site-specific surveillance in SCM-tested cases of colorectal cancer is necessary to validate this result.
Advances in Experimental Medicine and Biology, 1985
Humoral and cellular mechanisms of immune cytolysis, as effected by antibody and complement (Ab +... more Humoral and cellular mechanisms of immune cytolysis, as effected by antibody and complement (Ab + C') or by cytolytic T lymphocytes (CTL), have traditionally been considered the end result of early but terminal membrane damage, in turn causing colloid-osmotic lysis of the target cell. A comprehensive theory explaining and relating known prelytic cellular events to subsequent membrane damage is lacking, nor is there a specific picture as to the role and mode of action of Ca2+, which appears to be involved in both complement- and cell-mediated cytolysis (C'MC and CMC, respectively). Recent studies are in support of the view that both Ab + C' and CTL induce a comparable series of prelytic events, in the TC, initiated by membrane depolarization, which in turn bring about voltage-dependent Ca2+ influx or its intracellular release. Persistent elevation of cytosolic Ca2+ can induce massive stimulation of cellular ATPases (actomyosin, Ca2+) and cause exhaustive depletion of ATP. Consequently, Na+-pumping is slowed down and colloid-osmotic lysis ensues. Hence, in our view, membrane damage in immune cytolysis is the result rather than the cause of intracellular events culminating in lysis.
The intracellular fluorescein fluorescence polarization (IFFP) test indicates that peripheral blo... more The intracellular fluorescein fluorescence polarization (IFFP) test indicates that peripheral blood lymphocytes (PBL) of cancer patients display stimulatory sensitivity to a short incubation with specific tumor protein extracts. In this work, a human lymphocyte activation melanoma antigen (LAMA) was purified from supernatant of a human melanoma cell line (L1M1), which could specifically stimulate lymphocytes of melanoma patients. The results showed a significant stimulation of lymphocytes from healthy donors after incubation with phytohaemagglutinin (PHA), while no stimulation was observed after incubation with LAMA. On the other hand, lymphocytes from melanoma patients showed a significant stimulation with LAMA, while generally showing minor or no stimulation with PHA. Melanoma specificity of LAMA was demonstrated by no response in lymphocytes from patients of lung, colon, or breast cancer. The purified fraction is therefore considered to be a shared tissue-specific antigen which may be useful in immunodiagnosis and immunotherapy of melanoma.
Solutions containing heavy meromyosin, actin, native tropomyosin, and Mg-ATP exhibited streaming ... more Solutions containing heavy meromyosin, actin, native tropomyosin, and Mg-ATP exhibited streaming in horizontally placed glass microcapillaries. Up-hill streaming could also be observed when the capillaries were at an inclined position; this served for the clear distinction between active and passive streaming provided surface tension effects were eliminated. The presence of native tropomyosin and actin-activation of the ATPase activity of HMM were essential for the reconstitution of active streaming. The significance of the results for cytoplasmic streaming and muscle contraction is discussed.
The effectiveness of detecting melanoma by measuring the intracellular fluorescein fluorescent po... more 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.
Advances in Experimental Medicine and Biology, 1984
Attention is drawn to experimental results from many laboratories which indicate that the isometr... more Attention is drawn to experimental results from many laboratories which indicate that the isometric force (F) in the contraction of striated muscle fibers is linearly proportional to their variable cross-section area (A). Reversible swelling of intact, skinned, or glycinerated fibers can be induced by changes in tonicity, ionic strength or pH. In all cases where careful measurements of F and A are reported, the maximal isometric tension namely, T = F/A, is found around 1 kgf /cm2, even though F and A may change more than threefold for a given fiber at a certain length. These results seem to be independent of the fiber length or temperature. Thus, the isometric tension T in striated muscle does not depend on the number or the rate of the interacting cross-bridges. This result of constant isometric tension, which has so far received little attention, is however, a simple prediction of the hydraulic mechanism which is proposed for muscle contraction. Therefore, the hydraulic model, which is based on the hypothesis of vectorial flux of energetic protons deserves serious consideration.
Advances in Experimental Medicine and Biology, 1986
The mechanism whereby fixation of the membrane attack complex of complement (C') induces irre... more The mechanism whereby fixation of the membrane attack complex of complement (C') induces irreversible membrane damage ultimately leading to cell death may not be an exclusive membrane event. We investigated possible involvement of cellular metabolism in the lysis of nucleated cells induced 3by antibody (Ab) against cell surface antigens and C'. Using 31P-NMR spectroscopy we observed a marked reduction of creatine phosphate and relatively unaltered ATP levels shortly after the application of C', but prior to the onset of lysis. These metabolic changes preceded uptake of vital stairlT (e.g., eosine), or release of isotopically [\left( N{{a}_{2}}^{51}Cr{{O}_{4}} \right)\] -labeled cytoplasmic components. Monitoring the course of natural cell death over a 6-hr period revealed a comparable depletion of creatine phosphate prior to cell death. We would like to propose that membrane fixation of the C' attack complex induce metabolic depletion of high energy components which in turn cause irreversible cell swelling and membrane damage leading to cytolysis.
We analysed a series of 81 colorectal cancer cases in which the SCM (structuredness of the cytopl... more We analysed a series of 81 colorectal cancer cases in which the SCM (structuredness of the cytoplasmic matrix) test had already been performed with a diagnostic sensitivity of 92% and a specificity of 92.6%, yielding positive and negative predictive values of 96.3% and 84.7% respectively. We subdivided this group of 81 patients by anatomic location of the malignancy. Although the resultant subgroups were admittedly small, we noted a tendency for the most prominent changes in observed and calculated polarization parameters to be associated with cecal cancers. This finding was of special interest because the cecum is the most inaccessible site for colonoscopy. Ongoing site-specific surveillance in SCM-tested cases of colorectal cancer is necessary to validate this result.
Advances in Experimental Medicine and Biology, 1985
Humoral and cellular mechanisms of immune cytolysis, as effected by antibody and complement (Ab +... more Humoral and cellular mechanisms of immune cytolysis, as effected by antibody and complement (Ab + C') or by cytolytic T lymphocytes (CTL), have traditionally been considered the end result of early but terminal membrane damage, in turn causing colloid-osmotic lysis of the target cell. A comprehensive theory explaining and relating known prelytic cellular events to subsequent membrane damage is lacking, nor is there a specific picture as to the role and mode of action of Ca2+, which appears to be involved in both complement- and cell-mediated cytolysis (C'MC and CMC, respectively). Recent studies are in support of the view that both Ab + C' and CTL induce a comparable series of prelytic events, in the TC, initiated by membrane depolarization, which in turn bring about voltage-dependent Ca2+ influx or its intracellular release. Persistent elevation of cytosolic Ca2+ can induce massive stimulation of cellular ATPases (actomyosin, Ca2+) and cause exhaustive depletion of ATP. Consequently, Na+-pumping is slowed down and colloid-osmotic lysis ensues. Hence, in our view, membrane damage in immune cytolysis is the result rather than the cause of intracellular events culminating in lysis.
The intracellular fluorescein fluorescence polarization (IFFP) test indicates that peripheral blo... more The intracellular fluorescein fluorescence polarization (IFFP) test indicates that peripheral blood lymphocytes (PBL) of cancer patients display stimulatory sensitivity to a short incubation with specific tumor protein extracts. In this work, a human lymphocyte activation melanoma antigen (LAMA) was purified from supernatant of a human melanoma cell line (L1M1), which could specifically stimulate lymphocytes of melanoma patients. The results showed a significant stimulation of lymphocytes from healthy donors after incubation with phytohaemagglutinin (PHA), while no stimulation was observed after incubation with LAMA. On the other hand, lymphocytes from melanoma patients showed a significant stimulation with LAMA, while generally showing minor or no stimulation with PHA. Melanoma specificity of LAMA was demonstrated by no response in lymphocytes from patients of lung, colon, or breast cancer. The purified fraction is therefore considered to be a shared tissue-specific antigen which may be useful in immunodiagnosis and immunotherapy of melanoma.
Solutions containing heavy meromyosin, actin, native tropomyosin, and Mg-ATP exhibited streaming ... more Solutions containing heavy meromyosin, actin, native tropomyosin, and Mg-ATP exhibited streaming in horizontally placed glass microcapillaries. Up-hill streaming could also be observed when the capillaries were at an inclined position; this served for the clear distinction between active and passive streaming provided surface tension effects were eliminated. The presence of native tropomyosin and actin-activation of the ATPase activity of HMM were essential for the reconstitution of active streaming. The significance of the results for cytoplasmic streaming and muscle contraction is discussed.
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