Chromosomal radiosensitivity in meiotic oocytes of Chinese hamsters.

The X-ray sensitivity of unfertilized Chinese hamster oocytes was investigated. Female Chinese hamsters were exposed to a single X-ray dose of 200R at various preovulatory phases classified into 4 stages. These stages ranged from 12 hours to 5 estrous cycles before the time of collecting the oocytes. Chromosome analysis of the irradiated oocytes in metaphase-II was performed. The frequency of oocytes with abnormal chromosomes was compared with the non-irradiated control. The frequency of the oocytes with chromosome aberrations was 42.1% in the group in which females were irradiated at metaphase-I, 9.8% in the group irradiated at 2-4 days before the time of collecting the oocytes and 10.8% in that irradiated 1 estrous cycle before the time of collecting the oocytes. In the group irradiated at the 5th estrous cycle prior to the time of collecting the oocytes, the number of oocytes with chromosome aberrations could not be distinguished from that of the control. Comparing the frequency of oocytes carrying numerical chromosome aberrations with those carrying structural chromosome aberrations, there were more obvious differences in structural aberrations than in numerical ones among the irradiated stages. It was suggested that X-ray exposures of gonads, not only at postovulatory, but also preovulatory phases, may be hazardous and should be considered more carefully in the case of humans.

A theory of electrical conductivity of molten salt. II.

In molten equivalent salts, a unified relation that the ratio of partial dc conductivities is always equal to the inverse mass ratio, viz. sigma(+)/sigma(-)=m(-)/m(+), has been confirmed in view of microscopic point starting from the generalized Langevin equation. It has been newly proved that the memory functions assumed to be an exponentially decaying form in the Langevin equation for cation and anion are equal to each other. Furthermore, the short time behaviors of moving ions are analyzed in terms of their velocity correlation functions, according to the combination of generalized Langevin equation and damped Einstein oscillator equation. A minor correction for the expression of common friction constant derived before has been given. Estimated results for conductivities are close to those obtained by computer simulation and also comparable to experimental values.

Immune response to alien histocompatibility antigens on Epstein-Barr virus transformed cells.

Expression of alien histocompatibility antigens on Epstein-Barr virus transformed, cultured lymphoblastoid cell lines (LCL), which were established from normal peripheral blood lymphocytes (PBL), was studied by means of mixed lymphocyte reaction (MLR), cell mediated lysis (CML) and primed lymphocyte typing (PLT). Stimulation of PBL by autologous LCL resulted in some MLR responses and generation of cytotoxic effector cells against autologous LCL. Restimulation of PBL by 16 individual allogeneic PBL failed to prime an individual lymphocytes against autologous LCL in PLT tests. However, stimulation of PBL by a pooled normal PBL resulted in generation of cytotoxic cells against autologous LCL. Culturing of stimulated PBL in the presence of T cell growth factor (TCGF) for 30 days was shown to maintain cytotoxic effector cells in the cell population.

Distinctive sensitivity of some T-leukemia cell lines to L-asparaginase.

Forty-two human hematopoietic cell lines were assessed for sensitivity to a four-day incubation with L-asparaginase. Eight of 13 T-leukemia cell lines and 1 of 7 non-T, non-B common acute lymphoblastic leukemia cell lines exhibited an ID50 (50% growth inhibition dose) of less than 0.0001 IU/ml. Seven of these sensitive cell lines were further cultured in L-asparagine-free medium and were found not to proliferate. Five T-leukemia cell lines, 6 non-T, non-B common acute lymphoblastic leukemia cell lines, 10 "abnormal" B-cell lines, 4 "normal" B-cell lines, 3 myeloma cell lines and 5 myeloid leukemia cell lines had ID50 values between 0.1 and 1.0 IU/ml. Twelve of these resistant cell lines were able to proliferate in L-asparagine-depleted medium. The results indicate that some patients with T-cell acute lymphoblastic leukemia might respond to this enzymatic antineoplastic drug, L-asparaginase, at low dose.

Localized fatty infiltration of the liver. CT demonstration of its disappearance on treatment.

Two cases of localized fatty infiltration of the liver are reported, each of which demonstrated localized, well demarcated, abnormal low attenuation at computed tomography (CT), and were indistinguishable from malignant hepatic tumor. Following intravenous administration of contrast medium, normal blood vessel architecture within the low attenuation area was clearly demonstrated at CT. About three months thereafter, the fatty infiltrations had disappeared completely at CT following treatment of the underlying disease.

Preparation of phosphorylcholine derivatives of bovine serum albumin and their application to the affinity chromatography of C-reactive protein.

A simple method for the preparation of phosphorylcholine derivatives of bovine serum albumin (PC-BSA) by reductive alkylation of the amino groups of bovine serum albumin with choline phosphoryl glycoaldehyde is described. Choline phosphoryl glycoaldehyde was generated by periodate oxidation of glyceryl phosphorylcholine. PC-BSA was immobilized on SH-derivatized Toyopearl HW 65 by reacting the single SH group of PC-BSA with a bismaleimido reagent and then coupling maleimidated PC-BSA to the thiolated gel. The affinity purification of C-reactive protein (CRP), which is based on the Ca2+-dependent affinity of CRP for the phosphorylcholine residue of PC-BSA, was readily accomplished using the PC-BSA Toyopearl HW 65 column. The resulting CRP preparation from serum and pleural fluid was homogeneous as assessed by native polyacrylamide gel electrophoresis. PC-BSA derivatives were also shown to be reactive with Limulus polyphemus CRP.

Phenotyping of malignant hematopoietic cells. Analysis of 1200 cases of leukemia-lymphoma.

1255 cases of leukemia-lymphoma were tested between 1972 and 1984 by multiple marker analysis. Routine leukemia phenotyping was performed using standard morphological and cytochemical techniques in combination with clinical and histo-pathological information; the main emphasis was put on immunological surface marker analysis using erythrocyte rosette assays, TdT and a large panel of poly- and monoclonal antibody tests. The 1255 cases were divided into these major types and subtypes: 349 cases of ALL and related immature T- and Burkitt-lymphomas (cALL, pre B-ALL, B-ALL and Burkitt-lymphomas, T-ALL and immature, mostly leukemic T-lymphomas, Null-ALL), 454 cases of mature T- and B-cell malignancies (T-CLL, mycosis fungoides, Sezary-syndrome, T-lymphomas, B-CLL, hairy cell leukemia, multiple myeloma, B-lymphomas), 263 cases of acute myeloid leukemias (AML, AMMoL/AMoL), 182 cases of chronic myeloid leukemias (CML in chronic phase, CMoL, CML in blast crisis), 6 cases of erythroleukemia and 1 case of megakaryoblastic leukemia. A simplified classification scheme which has been used in our laboratories is presented. Phenotyping is of diagnostic, prognostic and therapeutic relevance, most evidently for patients with ALL. Routine leukemia phenotyping should be performed with highly standardized techniques and reagents and by combining information from several fields in the multiple marker analysis. New areas of leukemia research might become very useful for the routine procedure of phenotyping.

Nanoscale hydrophobic interaction and nanobubble nucleation.

We report large-scale atomistic simulation of midrange nanoscale hydrophobic interaction, manifested by the nucleation of nanobubble between nanometer-sized hydrophobes at constrained equilibrium. When the length scale of the hydrophobes is greater than 2 nm, the nanobubble formation shows hysteresis behavior resembling the first-order transition. Calculation of the potential of mean force versus interhydrophobe distance provides a quantitative measure of the strength of the nanoscale hydrophobic interaction.