Eur J Cancer Clin Oncol, 1989 May, 25(5), 777 - 83 Phenotyping of 76 human bladder tumors with a panel of monoclonal antibodies: correlation between pathology, surface immunofluorescence and DNA content; Hijazi A et al.; Phenotyping of 76 bladder tumors (11 grade I, 33 grade II and 32 grade III) has been carried out by flow cytometry on cell suspensions with simultaneous determination of DNA content and surface immunofluorescence using G4 and 5 new monoclonal antibodies (10D1, 7C12, 6D1, 3C6 and 12F6) directed against bladder tumor cells . Ten normal bladder samples were used as control . Antibodies 6D1 and 12F6 were specific for tumor cells whereas the others also labelled umbrella cells . Cells from grade I tumors were labelled with 10D1, 6D1, 7C12 and 12F6 antibodies, and cells of grade II tumors with 7C12 and to a lesser degree with 12F6 but not with 10D1 and 6D1 . Grade III tumor cells were specifically labelled with antibodies 3C6 and G4 . Reactivity of antibodies with tissue sections was well correlated with cytometry results, except for the antibody 3C6 . Finally, most of the cells stained by 3C6 and G4 were shown to have a DNA index greater than 1.0 . In conclusion cells of low grade tumors can be identified with 10D1 and 6D1 antibodies, and antigens recognized by 3C6 and G4 antibodies are mostly expressed by aneuploid cells. Neurochem Res, 1989 May, 14(5), 391 - 7 Na+, K+-ATPase activity in cultured C6 glioma cells; Folbergrova J et al.; Rat C6 glioma cells were cultured for 4 days in MEM medium supplemented with 10% bovine serum and Na+, K+-ATPase activity was determined in homogenates of harvested cells . Approximately 50% of enzyme activity was attained at 1.5 mM K+ and the maximum (2.76 +/- 0.13 mumol Pi/h/mg protein) at 5 mM K+ . The specific activity of Na+, K+-ATPase was not influenced by freezing the homogenates or cell suspensions before the enzyme assay . Ten minutes' exposure of glioma cells to 10(-4) or 10(-5) M noradrenaline (NA) remained without any effect on NA+, K+-ATPase activity . Neither did the presence of NA in the incubation medium, during the enzyme assay, influence the enzyme activity . The nonresponsiveness of Na+, K+-ATPase of C6 glioma cells to NA is consistent with the assumption that alpha (+) form of the enzyme may be preferentially sensitive to noradrenaline . Na+, K+-ATPase was inhibited in a dose-dependent manner by vanadate and 50% inhibition was achieved at 2 x 10(-7) M concentration . In spite of the fact that Na+, K+-ATPase of glioma cells was not responsive to NA, the latter could at least partially reverse vanadate-induced inhibition of the enzyme . Although the present results concern transformed glial cells, they suggest the possibility that inhibition of glial Na+, K+-ATPase may contribute to the previously reported inhibition by vanadate of Na+, K+-ATPase of the whole brain tissue. Immunology, 1989 May, 67(1), 96 - 102 Immunoregulatory properties of bone marrow-derived cells in the iris and ciliary body; Williamson JS et al.; Iris and ciliary body of mouse eyes have been examined for the presence of bone marrow-derived cells possessing the capability of functioning as antigen-presenting cells (APC) . We have determined that iris and ciliary body contain significant numbers of cells bearing T200, indicating their bone marrow origin . Most of these express the F4/80 marker typically found on mature macrophages . However, approximately one-third of the cells express Ia and a similar number express Mac-1 markers . Virtually none of the cells express Thy-1 or surface immunoglobulin . Whole preparations of excised iris/ciliary body, or single cell suspensions prepared from these tissues were then assayed for their capacity to induce proliferation among allogeneic lymphocytes . It was discovered that iris/ciliary body tissues or cells did not function as alloantigen-presenting cells, although tissue and cells derived from the corneal limbus were allostimulatory . In addition, iris/ciliary body tissues and cells displayed the ability to suppress mixed lymphocyte reactions to which they had been added as regulatory cells . We conclude that normal iris and ciliary body contain bone marrow-derived cells that fail to function as alloantigen-presenting cells . However, cells were present that have the capacity to inhibit alloimmune lymphocyte proliferation . The strategic location of inhibitory cells in the tissues that line the anterior chamber of the eye raises the possibility that these cells may play a role in the phenomenon of immunological privilege that is characteristic of this site. Eur J Immunol, 1989 May, 19(5), 955 - 8 Emigration of B cells from chicken bursa of Fabricius; Lassila O; The extent of emigration of cells from the bursa of Fabricius to the periphery was estimated . Per anum application of fluorescein isothiocyanate to label bursal cells in situ was used . Migrant cells can be visualized on frozen sections or cell suspensions of peripheral organs by their fluorescence . The data show that at 2-3 weeks after hatching about 5% of bursal cells leave the bursa per day . Since the bursal cells divide rapidly, this indicates that the vast majority (95%) of bursal cells die in situ . Cells that leave the bursa are surface IgM positive and go first to peripheral blood and later into B cell areas of spleen, thymus and cecal tonsils . The results are also discussed on the basis of their implication for the generation of antibody diversity in the chicken bursa. Am J Med Sci, 1989 May, 297(5), 314 - 20 Endothelial mediation is necessary for subsequent hepatocyte uptake of transferrin; Soda R et al.; The authors previously have reported on the presence of transferrin (TF) receptors on liver endothelial cells and have shown that hepatic uptake of transferrin-iron (TF-Fe) complexes in the liver is mediated by the endothelium . We now provide evidence that this endothelial cell mediation may be necessary for hepatocyte uptake of TF-Fe complexes . Transport of TF-Fe from endothelial cell to hepatocyte was studied in mixed cell suspensions in which radiolabeled TF-Fe complexes were incubated at 37 degrees C with the two cell populations purified and then mixed in equal ratios . The mixtures were then refractionated at various times after incubation and cell-associated radioactivities measured . Radiolabeled TF was rapidly taken up by the endothelial cell fraction, but radioactivity began to decline in this fraction as it increased in the hepatocyte fraction . In double labeling experiments with 125I-TF-59Fe, both radiolabels moved across the endothelium in parallel fashion, indicating that Fe remains associated with TF during transcytosis . However, in hepatocytes the two radiolabels became dissociated, with Fe remaining cell-associated and TF being recycled . Hepatocyte uptake of processed TF was partially inhibitable by galactan and asialofetuin, indicating that hepatocyte uptake may occur via asialoglycoprotein receptors of hepatocyte. J Biol Chem, 1989 Apr 15, 264(11), 6438 - 46 Association of glyceraldehyde-3-phosphate dehydrogenase with the plasma membrane of the intact human red blood cell; Rogalski AA et al.; Glycolytic enzymes have been observed to associate in vitro with membranes and cytoplasmic filaments in a variety of systems, but their distribution in vivo is contested . We have therefore examined the distribution of glyceraldehyde-3-phosphate dehydrogenase (G3PD) in the intact human erythrocyte using indirect immunofluorescence and affinity-purified rabbit antibodies to G3PD . Antibody specificity was demonstrated by immunoblotting as well as immunofluorescence experiments with ghosts specifically depleted of and reconstituted with G3PD . Anti-G3PD immunolabeling experiments utilized both fixed whole cells and fixed cell suspensions infused with 2.3 M sucrose, frozen and thick-sectioned . In all experiments a two-step fixation protocol was employed which ensured that cytoplasmic hemoglobin was retained when cells were subjected to Triton X-100 permeabilization, the anti-genicity of G3PD was preserved, and antibody penetration was complete . We used mixtures of biotinylated affinity-purified antibodies to G3PD and dichlorotriazinylaminofluorescein-labeled, affinity-purified antibodies to hemoglobin, followed by rhodamine-streptavidin, in double-label experiments . In both whole and sectioned human erythrocytes, G3PD staining was predominantly membrane associated while hemoglobin staining was diffusely distributed throughout the cytoplasm . In isolated ghosts, some G3PD was tightly bound to the membrane and was resistant to elution with phosphate-buffered saline and NAD+/arsenate . However, in immunolabeled rat reticulocytes and erythrocytes G3PD was cytoplasmic . Nucleated human blood cells and platelets also exhibited cytoplasmic G3PD . In approximately 10% of the human erythrocyte population G3PD was also cytoplasmic . These cells were flatter in shape and exhibited strong cytoplasmic immunolabeling for hemoglobin which was sometimes concentrated along the cell membrane; possibly, these cells were late reticulocytes or early erythrocytes . We conclude that G3PD is preferentially associated with the plasma membrane of human erythrocytes in a specific fashion. Experientia, 1989 Apr 15, 45(4), 363 - 5 Regular oscillations in suspensions of a putatively chaotic mutant of Dictyostelium discoideum; Goldbeter A et al.; We have tested the light-scattering properties of suspensions of the Dictyostelium discoideum mutant HH201 derived from the mutant Fr17 . Previous studies indicated that HH201 and Fr17 possess highly irregular rhythmic properties which might represent aperiodic oscillations, i.e . chaos . We report that the former mutant can display regular oscillatory behavior . Possible explanations for this result are discussed, including that of a transition from chaotic to periodic behavior resulting from some parameter change or from strong intercellular coupling in cell suspensions. J Urol, 1989 Apr, 141(4), 965 - 8 Cytotoxicity of high energy shock waves: methodologic considerations; Laudone VP et al.; In vivo and in vitro experimentation with high energy shock waves (HESW) is necessary to further our understanding of the biologic effects and potential application of this novel energy form . Factors are identified which are critical to the design and subsequent interpretation of HESW experimentation . First, the nature of the containment vessel and the presence or absence of acoustic interfaces are shown to significantly alter the outcome of cell suspension experiments . Second, the effects of HESW are shown to differ markedly for cells in suspension versus cells in tissue making comparisons between the two uncertain . Finally, the need for appropriate negative controls is demonstrated with in vivo experiments to control for the generalized toxicity which occurs when small animals are exposed to such an intense force distributed over a relatively large area . These findings affect the interpretation of previously reported work which investigated the cytotoxic potential of HESW. Zhonghua Nei Ke Za Zhi, 1989 Apr, 28(4), 222 - 5, 252 {Correlation study of in vitro tests with clinical response to ALG therapy in patients with severe aplastic anemia}; Ji SQ et al.; Fourteen patients with severe aplastic anemia were treated with antilymphocyte globulin (ALG) . Eight were studied with co-culture of patient's lymphocytes with normal bone marrow cells . Suppression of CFU-C was prevented by pretreatment of T lymphocytes with anti-T lymphocyte McAb in four patients and concordance with clinical outcome was observed only in two patients . Conclusive in vivo therapy result for this correspondence are lacking . Seven patients received fetal liver cell suspension infusion 24-36 hours after completing ALG therapy and remission were "more complete" in three cases with good response . Response of treatment in the fourteen patients was as follows: eight had complete or partial responses and the remaining did not respond or died (42.8%). Rev Fr Transfus Hemobiol, 1989 Apr, 32(2), 135 - 40 {HLA class II typing of peripheral blood B lymphocytes separated using monoclonal antibodies}; Lepage V et al.; The different methods proposed for preparation of B lymphocyte suspensions are not always simple, rapid and reliable . Presence of monocytes in the B cell suspension makes difficult HLA-DQ typing . For these reasons we propose a method using monoclonal antibodies (McAb) and complement to lyse the non B cells . Mononuclear cells, isolated from peripheral blood by Ficoll-Hypaque, are suspended in a mixture of anti-CD2, CD3, CD11b (OKM1 recognizing monocytes and granulocytes) McAb . This method of preparation of B cell suspension is rapid and provide better typing reactions than did the suspensions prepared by depletion of sheep red blood cell rosetting cells. No To Shinkei, 1989 Apr, 41(4), 383 - 90 {Cell kinetic analysis of human brain tumors by bivariate flow cytometric measurement of cellular DNA content and amount of incorporated bromodeoxyuridine}; Okuda Y et al.; Cell kinetics of 91 human brain tumors obtained from 88 patients were analyzed with the following two methods, 1) bivariate (two-color) flow cytometric measurement of cellular DNA content and amount of bromodeoxyuridine (BrdU) incorporated into cellular DNA, in 66 specimens, 2) immunohistochemical detection of BrdU incorporated S-phase cells, in 34 specimens . Patients were given an intravenous 1 hour infusion of 200 mg/sq . m . of BrdU 1-2 hours before the surgical removal . The excised tumor specimen was divided into several portions . One was fixed with 70% ethanol and embedded in paraffin, and another was digested mechanically and/or chemically to obtain a single cell suspension, and fixed in 70% ethanol . Paraffin-embedded tissue sections were stained by the peroxidase-antiperoxidase immunohistochemical method using anti-BrdU monoclonal antibody (MoAb) . Single cell suspensions were reacted with fluorescein isothiocyanate (FITC) conjugated anti-BrdU MoAb, or anti-BrdU MoAb and FITC-conjugated second antibody successively by the staining with propidium iodide, for flow cytometry (FCM) . Rates of S-phase fraction in single cell suspensions calculated by bivariate FCM were correlated well with labeling indexes (LI, i.e . the percentage of BrdU incorporated cells) calculated in tissue sections, but not with the result of analysis of DNA histogram by Dean's method . This discrepancy is probably due to large coefficient value in several samples . Histological malignancy of the tumors was reflected both in the proliferating index (PI, i.e . % S+G2M phase) calculated by bivariate FCM and the LI by immunohistochemical method . PI tended to be high in primitive neuroectodermal tumors and metastatic carcinomas, moderately high in gliomas, and low in benign tumor groups.(ABSTRACT TRUNCATED AT 250 WORDS) Br J Pharmacol, 1989 Apr, 96(4), 773 - 8 Na+ -K+ pump activity in rat peritoneal mast cells: inhibition by extracellular calcium; Knudsen T et al.; 1 . Pure populations of rat peritoneal mast cells were used to study cellular potassium uptake . The radioactive potassium analogue, 86rubidium, was used as a tracer for potassium for measurements of the activity of the cellular potassium uptake process . 2 . The ouabain-sensitive and the ouabain-resistant potassium (86rubidium) uptake of mast cells incubated in the presence of calcium, 1 mmol l-1, were very low, 52 and 147 pmol per 10(6) cells min-1 . 3 . Calcium-deprivation of the cells uncovered a large capacity ouabain-sensitive potassium (86rubidium) uptake mechanism . The activity of the uptake mechanism was decreased by reintroduction of calcium into the cell suspension, and it was dependent on cellular energy metabolism, temperature and pH . 4 . The potassium (86rubidium) uptake of mast cells incubated in a calcium-free medium occurs through an active and ouabain-sensitive mechanism that has the nature of an enzyme, and it is mediated by the Na+ -K+ pump located in the plasma membrane . It is demonstrated that the activity of the Na+ -K+ pump mechanism is inhibited by low concentrations of extracellular calcium (0.1-1.2 mmol l-1) . The possibility is discussed that calcium-deprivation may increase the pump activity by increasing the permeability of the plasma membrane for Na+. J Bone Miner Res, 1989 Apr, 4(2), 259 - 68 Bone resorption by isolated human osteoclasts in vitro: effects of calcitonin; Murrills RJ et al.; Human osteoclasts were isolated from 12- to 17-week-old fetal tissue and from transiliac crest bone biopsies for an in vitro study of their biology . A hypodermic needle was used to flush either the fetal long bones or the trabeculae of the iliac crest bone biopsy with tissue culture medium and the resulting cell suspension sedimented briefly either onto the surface of plastic tissue culture dishes, for time-lapse microcinematography, or onto slices of devitalized bovine cortical bone for quantitative assay of bone resorption . The osteoclasts were motile, tartrate-resistant acid phosphatase positive and capable of excavating pits in slices of devitalized bovine cortical bone . Human calcitonin, at doses of 1 ng/ml and 1 microgram/ml, caused a 70% inhibition of bone resorption by human fetal osteoclasts over a 24 h period but had no apparent effect on the morphology or motility of either fetal or adult osteoclasts. Int J Artif Organs, 1989 Apr, 12(4), 270 - 5 Endothelial cell seeding on PTFE vascular prostheses using a standardized seeding technique; Gerlach J et al.; A standardized method was developed for seeding endothelial cells (EC) in tubular vascular grafts . A rotational cell seeding device for tubular prostheses is presented and parameters influencing the kinetics of cell adhesion (rotation speed, graft diameter, cell suspension level, inoculated cell number) are reported . Seeding EC in 14 mm ID PTFE vascular grafts with rotation rate of 10 rph gave an adhesion rate of 80% in a homogeneous monolayer. Cell Calcium, 1989 Apr, 10(3), 171 - 80 Measurement of cytoplasmic calcium concentration in cell suspensions: correction for extracellular Fura-2 through use of Mn2+ and probenecid; McDonough PM et al.; 1321N1 astrocytoma cells loaded with Fura-2 were found to continuously transport Fura-2 to the extracellular medium . To correct for extracellular Fura-2 fluorescence a protocol was developed in which Mn2+ was added to duplicate cuvettes of cells to quench extracellular Fura-2 at the beginning and end of the experimental time course . Since the export of Fura-2 was linear with time, two separate quench determinations allowed the amount of fluorescence from extracellular Fura-2 fluorescence to be estimated at every point in the time course and subtracted from the data . The uncorrected and Mn2+-corrected basal cytoplasmic calcium concentrations averaged 153 nM and 72 nM, respectively . The peak intracellular calcium concentrations following muscarinic stimulation with 300 microM carbachol averaged 1159 nM (uncorrected) and 889 nM (Mn2+-corrected) . Probenecid (2.5 mM) was found to block the export of Fura-2 from these cells and did not change the basal calcium concentration or the muscarinic calcium response. Int J Radiat Oncol Biol Phys, 1989 Apr, 16(4), 1111 - 4 Toxicity of RSU-1069 for KHT cells treated in vivo or in vitro: evidence for a diffusible toxic product; Hill RP et al.; RSU-1069 is a highly effective hypoxic cell cytotoxin in KHT sarcomas treated in vivo . However, relative to the hypoxic cells, the oxic cells in the tumor appear more sensitive to the drug than would have been predicted on the basis of results with CHO (AA8-4) cells treated in vitro with the drug under oxic and hypoxic conditions . To examine possible reasons for this difference, suspensions of KHT cells were prepared from tumors growing in vivo, and treated with RSU-1069 in vitro under oxic or hypoxic conditions . The sensitivity of the KHT cells was similar to that of AA8-4 cells, regardless of whether the cells were obtained from untreated tumors or from tumors given 15 Gy in vivo just prior to the preparation of the cell suspension . We observed, however, that the sensitivity of both AA8-4 cells and KHT cells to drug treatment under hypoxic conditions increased with the density of the cells in the treated suspension . This result suggests the possibility that a diffusible toxic product may be released from cells . Such a product could contribute to the toxicity of the drug for oxic cells in tumors in situ. Invest Ophthalmol Vis Sci, 1989 Apr, 30(4), 714 - 6 In vitro inhibition of lens epithelial cell growth by continuous wave Nd:YAG laser; Miyake K et al.; Bovine lens epithelial cells were suspended in MEM medium and subjected to continuous wave, low power, pulsed neodymium:yttrium-aluminum-garnet (Nd:YAG) laser irradiation . The temperature of each suspension was maintained at 36 degrees C . Laser applications ranged from 1 to 10 watts and from 100 to 2000 seconds, but the total dose to each of the epithelial cell suspension was 2000 J . Six to thirty-nine percent of the cells were dead immediately after irradiation . Surviving cells, cultured for 15 days, showed decreased attachment and failed to grow . These preliminary results suggest that the Nd:YAG laser may be used during cataract surgery to prevent subsequent lens epithelial cell proliferation and the resulting vision reduction and glare. J Clin Lab Immunol, 1989 Apr, 28(4), 161 - 8 A cytotoxic monoclonal islet cell surface antibody from the NOD mouse; Pontesilli O et al.; Monoclonal antibody (Mab) 1.93B7 was obtained by fusion of spleen cells from a diabetic NOD mouse with P3X63Ag8.653 myeloma cells and screening for complement mediated lysis of rat insulinoma (RIN) cells . Immunofluorescence studies revealed that this Mab binds to RIN cells but not to the rat pituitary tumour line GH3 . The binding of Mab 1.93B7 to RIN cells was abolished by trypsin but not by neuraminidase treatment of the cells, suggesting that the antigen recognized is a protein . Mab 1.93B7 bound to approximately 30% of mouse (BALB/c) and rat islet cells which had been subjected to trypsin digestion and incubated as a single cell suspension for 12h to allow reexpression of trypsin sensitive antigens . Since Mab 1.93B7 is potentially pathogenic, as suggested by its reactivity to primary islet cells and its complement fixing capacity, we injected it into BALB/c and NOD mice . Cytotoxic activity against RIN cells was detected in the serum of the animals injected with Mab 1.93B7, but the Mab did not exert a diabetogenic action and failed to reverse diabetes when administered at onset in NOD mice . No modification of the course of spleen cell mediated transfer of diabetes in NOD mice was observed when the Mab was administered from the time of spleen cell inoculation to the appearance of glycosuria . The implications of the lack of an effect in vivo of Mab 1.93B7 under the conditions employed are discussed. Crit Care Clin, 1989 Apr, 5(2), 331 - 52 Induction of tissue injury and altered cardiovascular performance by platelet-activating factor: relevance to multiple systems organ failure; Lefer AM; PAF is a phospholipid formed from the action of phospholipase A2 upon cellular membranes in response to immunologic or hypoxic stimuli . PAF does not exist in its active form as a storage product within cells, but is synthesized rapidly after phospholipase A2 activation . A potent lipid released by multiple cell types in mammalian systems, the emerging perspective is that PAF is a major endogenous mediator influencing the pathogenesis and outcome of ischemia and conditions of circulatory shock . These effects appear to be especially relevant to the syndrome of MSOF during critical illness . All of the major criteria for validation of a shock factor have been fulfilled for PAF . First, PAF has been measured in biological fluid of animals during shock states, although this is not an easy task since PAF is formed in minute amounts and is rapidly metabolized . Nevertheless, combinations of high pressure liquid chromatography (HPLC) and bioassay methods employing washed rabbit platelets have been successfully utilized in this regard . Second, synthetic PAF has been injected into cell suspensions, isolated tissues, and live animals, where it produces most of the effects attributed to endogenous PAF released by immunologic or hypoxic stimuli . These studies have shown that PAF exerts a variety of pathophysiologic actions, including (1) cardiodepression (that is, a negative inotropic effect), (2) reductions in systemic blood pressure, (3) leakage of fluid from the microvasculature, (4) bronchoconstriction, and (5) platelet aggregation . All of these actions of PAF can initiate or exacerbate shock and ischemic injury in multiple organ systems . Third, specific PAF receptor antagonists have been found to markedly attenuate the severity of endotoxic, anaphylactic, hemorrhagic, and traumatic shock, as well as acute myocardial ischemia . In all these conditions, a variety of PAF receptor antagonists (including PAF analogues and structurally dissimilar substances) have improved survival and have retarded pathophysiologic processes believed to be important in causing tissue injury . These processes include lysosomal membrane damage and proteolysis . Moreover PAF receptor antagonists attenuate the release of secondary toxic factors in shock, such as myocardial depressant factor . Thus, administration of specific PAF receptor antagonists early in the course of circulatory shock and organ ischemia may prove to be useful therapeutic agents in a variety of life-threatening disorders . In addition to having direct actions, PAF appears to function as a pivotal agent in a chain of mediators producing tissue injury . Recent evidence suggests that tumor necrosis factors (i.e., cachectin) stim J Histochem Cytochem, 1989 Apr, 37(4), 509 - 13 Detection of terminal deoxynucleotidyl transferase (TdT) by flow cytometry in leukemic disorders; Bardales RH et al.; We applied a new technique to the detection of intracellular TdT in 26 leukemic patients, including 16 non-T acute lymphoblastic leukemia (ALL), four T-ALL, one T-lymphoblastic lymphoma in leukemia phase, one undifferentiated leukemia, one de novo lymphoblastic phase of chronic myeloid leukemia, and three acute monocytic leukemias (AMOL) . Mononuclear cell suspensions were incubated in saponin to permeabilize the cell membrane . The cells were then stained by indirect immunofluorescence (IF) using anti-human TdT monoclonal antibodies and were analyzed by flow cytometry (FCM) . The TdT results were compared with those obtained by biochemical TdT assay (26 cases), immunoperoxidase determination (PAP) (12 cases), and fluorescence microscopy (seven cases) . The results obtained by PAP and fluorescence microscopy were 100% concordant with those obtained by FCM and biochemical assay . TdT determination by FCM allows the analysis of large numbers of cells in a fast, objective, and reliable manner, as compared with biochemical assay, PAP, and fluorescence microscopy determinations. Int J Radiat Biol, 1989 Apr, 55(4), 705 - 15 A single-shot rapid-mixing device for radiobiological studies with mammalian cells; Hodgkiss RJ et al.; A single-shot rapid-mixing device is described for the rapid addition of solutions of radiation-modifying agents, to cell suspensions, at well-defined times relative to a pulse of radiation . The liquid injection system could be used to initiate or quench a wide range of chemical or biochemical reactions . The rapid-mixing device is based on a syringe driven by a stepper motor and can inject up to 2 cm3 liquid in less than 100 ms . The radiation source, a 4 MV Van de Graaff accelerator, provides an electron beam which is deflected from the beam dump on to the sample in two stages, providing a 10 ms radiation pulse . A digital delay circuit defines the interval between mixing and irradiation . The apparatus has been designed to study the kinetics of processes that occur over a time range extending from about 0.1 s to some minutes . It bridges the gap between the ranges available with conventional fast-mixing and those using standard X- or gamma-irradiation methods . The time resolution of the technique has been examined by following the timecourse of radiosensitization by oxygen in mammalian cells . The timecourse of radioprotection of aerobic mammalian cells by dithiothreitol has been measured using the technique. Am J Clin Pathol, 1989 Apr, 91(4), 417 - 21 A method for measuring lymphocyte proliferation in mixed lymphocyte cultures using a nuclear proliferation antigen, Ki-67, and flow cytometry; Palutke M et al.; The mixed lymphocyte culture procedure using tritiated thymidine (3H-TdR) incorporation is time consuming and labor intensive, therefore costly . With the use of a fluorescent antibody to a human nuclear proliferation antigen, Ki-67, and flow cytometry, mixed lymphocyte cultures on 20 families of renal and bone marrow transplant patients and normal controls were performed . In this method for measuring lymphocytic proliferation, previously developed by the authors, the entire culture and staining procedures are performed in microculture plates . Finally, the cell suspensions are aspirated with a microsampler to be analyzed by a flow cytometer . Excellent correlation of the percentage of Ki-67-positive cells and the counts per minute (CPM) of 3H-TdR incorporated into the DNA was obtained . This method eliminates the use of radioactive labels, is less time consuming, and yields results two to three days earlier than the radioactive method . In addition, the authors dual-labeled the lymphocyte nuclei with Ki-67 and propidium iodide (Ki-67/PI) . This permitted the comparison of the appearance of nuclear antigen with the various phases of the cell cycle. Exp Clin Endocrinol, 1989 Apr, 93(1), 61 - 8 Changes of dipeptidyl peptidase (DP IV) activity in the T lymphocytes of rats following administration of ACTH, dexamethasone and opiates; Koranyi L et al.; The aim of the work was to study the effect of glucocorticoids, opiates and stressful stimuli on dipeptidyl peptidase IV (DP IV, EC 3.4.14.5) activity of T lymphocytes prepared from the thymus of intact and adrenalectomized rats . Four week old male rats of Wistar strain were used . The in vivo administration of ACTH, dexamethasone and morphine treatment resulted in an increase of DP IV activity in the cell suspension . In adrenalectomized rats ACTH treatment failed to modify the enzyme activity, however, pain or emotional stress resulted in an elevated DP IV activity . Morphine and D-Met2-Pro5-enkephalinamide resulted in a dose dependent activation of DP IV in T cells, an effect which could be modified by naloxone pretreatment . Our findings show that DP IV mechanisms in T cells are highly sensitive to exogenous and endogenous steroids, opiates and biologically active substances released in response to stress in rats. J Clin Pathol, 1989 Apr, 42(4), 427 - 31 Cell suspensions from collagenase digestion of bone marrow trephine biopsy specimens; Ades CJ et al.; A technique for the extraction of cells from bone marrow trephine core biopsy specimens using collagenase digestion was assessed in 39 cases (33 diagnostic and six normal) . Diagnostically useful numbers of cells were extracted from all marrows . Morphological assessment of cytocentrifuge preparations of these cells gave a correct diagnosis in 23 (60%) of cases compared with 27 (70%) for the corresponding aspirated marrow smears . Phenotypic analysis using flow cytometry showed persistence of a range of surface membrane antigens following collagenase digestion . Increased autofluorescence was a problem in some cases . Cytochemistry, bone marrow culture, and cytogenetic analysis could also be carried out on these cells . It is concluded that this technique has useful diagnostic applications in cases of dry taps. Am J Physiol, 1989 Apr, 256(4 Pt 1), G808 - 16 Secretagogue-induced protein phosphorylation and chloride transport in Caco-2 cells; Burnham DB et al.; The effects of vasoactive intestinal polypeptide (VIP), 16,16-dimethyl prostaglandin E2 (DMPGE2) and dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP) on protein phosphorylation were studied in relation to stimulation of chloride transport in cell suspensions of the human colon epithelial cell line Caco-2 . In 36Cl-loaded cells, VIP and DMPGE2 within 1 min decreased cellular chloride content 35-40%, with half-maximal effects being elicited at 1.0 and 85 nM concentration, respectively . A similar effect on chloride content occurred after 10 min of treatment with 0.5 mM DBcAMP . For all three secretagogues, decreases in cellular chloride content were associated with increases in membrane permeability to chloride . DMPGE2 and VIP within 1 min, and DBcAMP within 10 min, increased the phosphorylation of an unidentified soluble protein of Mr = 42,000 and pI = 6.1, and of a protein of Mr = 20,200 and pI = 4.9 identified as myosin regulatory light chain . Between 10 and 30 min of stimulation, however, phosphorylation of the Mr = 42,000 protein and chloride transport activity remained elevated in DMPGE2- and DBcAMP-treated cells, whereas light chain phosphorylation returned to control level . No effect of secretagogues on phosphorylation was detected in the total particulate fraction or an integral membrane protein fraction . It is concluded that increased membrane permeability to chloride induced by cAMP-mediated secretagogues in Caco-2 is temporally associated with the increased phosphorylation of a Mr = 42,000 soluble protein. Nippon Ika Daigaku Zasshi, 1989 Apr, 56(2), 187 - 95 {Suppressor T cells against delayed type hypersensitivity to Mycobacterium intracellulare}; Kitamura K; Mycobacterium intracellulare Mino strain (Mino) grows progressively in the organs of susceptible mice, such as C57BL/6, C57BL/10 or BALB/c . It is very difficult to induce acquired immunity against M . intracellulare in those susceptible mice . C57BL/6 (B6) mice show no or very weak delayed type hypersensitivity (DTH) to partially purified Mino antigens when sensitized with 10(7) living Mino subcutaneously . B6 mice pretreated with cyclophosphamide (CY) showed enhanced DTH to Mino, suggesting that suppressor mechanism exists in this system . Whether or not such a suppressor mechanism exists in the induction phase of DTH (A) and/or in the expression phase of DTH (B) was examined by cell transfer experiments . Recipients for testing (A) were B6 mice receiving CY 2 days before an immunization, and those for (B) were B6 mice receiving both CY and subcutaneous injections of Mino 3 weeks before the cell transfer . B6 mice which were intravenously injected with Mino a week or 6 weeks before preparing spleen cell suspension, were used as the donors . Single cell suspensions of the spleens were plated on tissue culture dishes and non-adherent cells were harvested after incubating for 60 min at 37 degrees C . These cells were used for cell transfer . In the induction phase experiment, recipient mice received the cells before sensitization, while they received the cells after sensitization in the expression phase experiment . DTH were markedly suppressed in the cell transferred groups as compared with the non-transferred groups . This activity disappeared by treatment of the transferred cells with antibody (alpha Thy-1 Ab) and complement.(ABSTRACT TRUNCATED AT 250 WORDS) Agents Actions, 1989 Apr, 27(1-2), 93 - 6 Passive sensitization of human intestinal mast cells; Nolte H et al.; Dispersed human intestinal mast cells were used for passive sensitization experiments . Eight biopsies (9.7 +/- 1.2 mg/biopsy) of human duodenum were collected from non-atopic children (5) and adults (5) . The tissue was dispersed mechanically and enzymatically to yield single cell suspensions . The method produced 2 x 10(3) mast cells per mg wet weight of tissue in a purity of 2.8% . Passive sensitization of the mast cells was performed with the patients' own plasma and plasma obtained from atopic donors . The non-atopic mast cells were able to bind the allergen-specific IgE . In addition, passive sensitization with atopic donor-plasma enhanced the cell sensitivity and cell reactivity to anti-IgE challenge, but had no effect on the cellular response to the ionophore A23187 . The study shows that the enzymatic dispersion of human intestinal mast cells produces functionally intact mast cells with preserved Fc-receptors which can be passively sensitized. Agents Actions, 1989 Apr, 27(1-2), 101 - 3 Histamine release from canine lung and liver mast cells induced by radiographic contrast media; Ennis M et al.; Radiographic contrast media are commonly used diagnostic aids to improve imaging, e.g . in computerized tomography . However, the routine application of these agents may cause adverse allergic/pseudoallergic reactions . In order to understand more completely the underlying mechanisms involved in these reactions, experiments on histamine release both in vivo and in vitro are necessary . Using canine mast cell suspensions from lung and liver, we have investigated the histamine release caused by six commonly used preparations . The dog is an ideal model for both in vitro and in vivo studies not only by virtue of its size but also because of its similarity to man with respect to e.g . cardiovascular reactions after drug-induced histamine release . The two non-ionic preparations (Solutrast, Ultravist) released little histamine from both cell types (ca . 4-6%) . The ionic contrast media (Angiographin, Hexabrix, Telebrix, Rayvist) dose-dependently released histamine from the liver cells and pulmonary cells (maximum release between 18-35%) . The liver cells (the liver is the shock organ in the dog) reacted more strongly to these agents than the pulmonary cells, thus providing further evidence for mast cell heterogeneity and the importance of selecting the appropriate mast cell model for the investigation. Jpn J Cancer Res, 1989 Apr, 80(4), 341 - 7 Enhanced liver metastatic potential of alpha-fetoprotein-producing human gastric carcinoma after carbon tetrachloride-induced liver damage in nude mice; Sawada H et al.; The liver metastatic potential of alpha-fetoprotein (AFP)-producing human gastric carcinoma (NSC-3) was examined in male, BALB/c, nude mice . Metastatic nodules in the liver were produced by intrasplenic (IS) injection of tumor cell suspension prepared by trypsinization from subcutaneous NSC-3 tumor . The serum AFP level increased exponentially after IS injection along with the growth of metastatic nodules in the liver, and a positive correlation was observed between the estimated weight of metastatic nodules and serum AFP level . To investigate the effect of liver damage by carbon tetrachloride (CCl4) on the metastatic potential of NSC-3 cells injected intrasplenically, the mice were divided into 4 groups: Group 1 received IS injection of 1 x 10(6) of NSC-3 cells without CCl4 treatment; Groups 2, 3 and 4 received IS injection 7 days, 2 days and 1 day after CCl4 treatment, respectively . All mice were killed 64 days after IS injection . The incidence of liver metastasis was 80% in Group 1, but 100% in Groups 2, 3 and 4 . The mean numbers of metastatic nodules per liver were 4.2 in Group 1, 16.8 in Group 2, 18.0 in Group 3 and 44.5 in Group 4 . Significant differences in the mean numbers of metastatic nodules were observed between Group 4 and the other groups . It was clearly demonstrated that the metastatic potential of AFP-producing human gastric carcinoma cells (NSC-3) is enhanced in the situation prevailing after liver parenchymal cells are damaged by CCl4. Exp Neurol, 1989 Apr, 104(1), 1 - 9 Nimodipine enhances growth and vascularization of neural grafts; Finger S et al.; The potential of the calcium channel antagonist, nimodipine, to enhance vascularization and growth of neural grafts has been investigated . Four groups of rats received unilateral 6-OHDA lesions of the nigrostriatal pathway followed 16-23 days later by intrastriatal grafts of embryonic ventral mesencephalon . The grafts were derived from (i) Embryonic Day 14 embryos (group E14), (ii) Day 17 embryos (group E17), and (iii) Day 20 embryos (group E20), all implanted within 90 min of preparation, or (iv) Day 14 embryos with a 6-h delay prior to implantation (group E14/6H) . Half the rats in each group received intragastric intubation with nimodipine daily for 14 days after transplantation surgery, whereas the other half received control intubations . The rats were killed by perfusion with formalin containing Indian ink 6 weeks after grafting . Nimodipine treatment enhanced the vascularization of the grafts in all four groups and induced a significant increase in the volume of grafts under the three suboptimal transplantation conditions (i.e., groups E17, E20, E14/6H) . The results suggest that vascularization of graft tissue is an important determinant of survival and growth of neural transplants prepared by the dissociated cell suspension technique and show that vascular perfusion of grafts can be enhanced by nimodipine. Eur J Biochem, 1989 Mar 15, 180(2), 421 - 7 In vivo 31P- and 13C-NMR studies of ATP synthesis and methane formation by Methanosarcina barkeri; Santos H et al.; Carbon and phosphorus metabolism of cell suspensions of Methanosarcina barkeri strain MS (DSM 800), grown on methanol, were probed in vivo by NMR . The experimental conditions, which involved thick cell suspensions, did not significantly affect the efficiency of the rate of methanol uptake by cells . Following exposure to methanol an acidification of both the intracellular and the extracellular spaces was observed and a gradient of 0.5 pH units across the cytoplasmic membrane was determined from the 31P-NMR data . High levels of intracellular ATP up to 4 mM were detected . The ADP concentration determined in a suspension of starved cells was only 2 mM, suggesting that a significant amount of ADP may be immobilized and is thus not detectable by NMR . In the presence of the protonophore, 3,3',4',5-tetrachlorosalicylanilide, the proton gradient was dissipated and the synthesis of ATP stopped . The inhibitor of the ATP synthase, N,N'-dicyclohexylcarbodiimide, was rather inefficient in inhibiting ATP synthesis . High concentrations of N,N'-dicyclohexylcarbodiimide (corresponding to 300 nmol/mg protein-1) were required to decrease the ATP content by approximately 60%, and, under these conditions, formation of acetyl phosphate was detected . However, the methanol consumption rate was not affected. J Biol Chem, 1989 Mar 15, 264(8), 4324 - 8 Activation of protein kinase C modulates the adenylate cyclase effector system of B-lymphocytes; Wiener E et al.; Antibodies to surface immunoglobulins activate inositol phospholipid hydrolysis in B-lymphocytes, but very little is known concerning their effects on cAMP levels . In other cells, products from the hydrolysis of phosphatidylinositol 4,5-bisphosphate can increase and/or potentiate cAMP accumulation . In this study we have examined whether goat anti-mouse IgM (mu-chain-specific) stimulates and/or potentiates increases in the cAMP levels of splenocytes from athymic nude mice . Goat anti-mouse IgM, by itself, stimulated a 60% increase in cAMP within 2 min . Pretreating the cell suspensions at 37 degrees C with anti-IgM produced opposite effects on the forskolin- and prostaglandin E1 (PGE1)-induced increase in cAMP . Anti-IgM (25 micrograms/ml) potentiated the rise in cAMP induced by 100 microM forskolin 76%, but it decreased the response to 50 nM PGE1 by 30% . Direct activation of protein kinase C (Ca2+/phospholipid-dependent enzyme) by 12-O-tetradecanoylphorbol 13-acetate and/or sn-1,2-dioctanoylglycerol resulted in a similar pattern of responses . A 3-min preincubation with 97 nM 12-O-tetradecanoylphorbol 13-acetate potentiated the forskolin-induced response from 1.7 +/- 0.1 to 4.3 +/- 0.6 pmol of cAMP/10(6) cells but reduced the PGE1 response from 0.98 +/- 0.06 to 0.51 +/- 0.03 pmol of cAMP/10(6) cells . Similarly, preincubating the cells for 3 min with 5 microM sn-1,2-dioctanoylglycerol increased the forskolin response from 1.7 +/- 0.1 to 5.1 +/- 0.2 pmol of cAMP/10(6) cells but reduced the response to PGE1 from 1.15 +/- 0.03 to 0.75 +/- 0.04 pmol of cAMP/10(6) cells . Thus, activation of protein kinase C by hydrolysis products of inositol phospholipids, 12-O-tetradecanoylphorbol 13-acetate, or exogenous diacylglycerols modified adenylate cyclase itself and sites upstream of adenylate cyclase such as the receptor or G proteins coupling the receptor to the cyclase . Furthermore, modification of the PGE1 response by anti-IgM provides a mechanism by which antigen can differentially regulate T- and B-cells responding to macrophage-produced prostaglandins during an immune response. J Theor Biol, 1989 Mar 7, 137(1), 55 - 69 Magnetic potential and field gradients of a model cell; Mendz GL et al.; The magnetic potential within and outside a nucleated cell placed in a uniform magnetic field is described for a model consisting of two concentric diamagnetic spheres . The analytical description of the magnetic potential in and around a system consisting of a finite number of concentric diamagnetic spheres in a uniform magnetic field was derived . The solution was employed to calculate the field gradients outside and inside a model chicken red blood cell . The form and magnitude of the gradients provide a theoretical basis on which to discuss experimental results relating to the attenuation of signals obtained using proton nuclear magnetic resonance spectroscopy with chicken erythrocyte suspensions . The form of the magnetic field, field difference and field gradients in the external medium of a cell suspension was simulated for a distribution of spheres in a uniform magnetic field, such as might occur in an idealised dilute cell suspension. Int J Radiat Oncol Biol Phys, 1989 Mar, 16(3), 755 - 61 Misonidazole binding in SCCVII tumors in relation to the tumor blood supply; Olive PL et al.; Misonidazole (MISO) binding was examined in murine squamous cell carcinomas as a function of distance from the tumor blood supply . C3H mice bearing subcutaneous SCCVII tumors were injected intraperitoneally with 3H-MISO followed at various times later by intravenous injection or infusion of the fluorescent perfusion probe, Hoechst 33342 . Tumors were then excised, and single cell suspensions prepared for fluorescence activated cell sorting . Cells sorted on the basis of Hoechst 33342 fluorescence were examined for 3H-MISO content by liquid scintillation counting or autoradiography . MISO content in the 10% of cells most distant from the blood supply was as much as 8 times greater than the amount in the 10% of cells closest to the blood supply . The largest differentials in MISO content between dimly and brightly staining regions were obtained if (a) tumors greater than about 300 mg were used, (b) at least 3 hr were allowed for MISO metabolism and binding prior to analysis, and (c) cell sorting was performed on the basis of concentration of Hoechst (correcting for cell size) rather than on the basis of total fluorescence intensity per cell . As tumors enlarged, MISO content increased even in the cells closest to the blood supply suggesting a decrease in net tumor oxygenation perhaps caused by intermittent hypoxia. Am J Reprod Immunol, 1989 Mar, 19(3), 92 - 8 Membrane fluidity of trophoblast cells and susceptibility to natural cytotoxicity; Szekeres-Bartho J et al.; This study examines the relationship between membrane lipid microviscosity and susceptibility of villous trophoblast to lysis by natural cytotoxic cells . Trophoblast-enriched cell suspensions prepared from term human placentae were treated with cholesteryl hemisuccinate (CHS)--a modulator of membrane lipid microviscosity . CHS-treated cells were more susceptible targets for natural lymphocyte cytotoxicity than were untreated controls . In binding experiments, increased binding of lymphocytes to CHS-treated target cells was found . Preincubation with progesterone prevented membrane rigidification by CHS . Progesterone, cortisol, and estriol restored the impaired resistance of CHS-treated trophoblast cells to lysis . We determined microviscosity and progesterone concentration in villous surface membranes, prepared from placentae from idiopathic spontaneous abortions and normal first-trimester pregnancies . An inverse relationship was found between progesterone content and microviscosity of the membranes . Microviscosity of the membranes from abortion placentae was significantly higher (P less than .01) and progesterone concentration was significantly lower (P less than .001) than those in the membranes of normal first trimester placentae. Neuroendocrinology, 1989 Mar, 49(3), 262 - 6 Testicular interstitial cells as targets for peripheral benzodiazepines; Ritta MN et al.; We evaluated the 'in vitro' effect of a selective peripheral benzodiazepine (BZD) receptor agonist, Ro 5-4864, on basal and hCG-stimulated androgen production by testicular interstitial cell suspensions . Ro 5-4864 (10(-9)-10(-5) M) induced a significant increment of basal testosterone release into the medium . In addition, under conditions of hCG stimulation, Ro 5-4864 (10(-7) M) induced a potentiated response to the gonadotropin in a dose-dependent manner . The selective peripheral BZD antagonist PK 11195 fully prevented the stimulatory effect of Ro 5-4864 . On the other hand, clonazepam, a central BZD agonist, failed to affect androgen production significantly, whereas diazepam (10(-5)-10(-4) M), which binds to both central and peripheral BZD receptors, was able to induce a significant increment of basal and hCG-stimulated testosterone production . These results suggest that under our experimental conditions Ro 5-4864 exerts an effect on testicular steroidogenesis, presumably through binding to the previously described peripheral-type BZD receptor. J Neurosci Methods, 1989 Mar, 27(2), 121 - 32 In vitro and in vivo transplantation of fetal rat brain cells following incubation with various anatomic tracing substances; Stoppinni L et al.; Implantation of fetal brain regional anlage into host brains ('brain transplantation') holds promise as a plausible treatment for certain human neurodegenerative disorders . Improvements in experimental brain transplantation techniques include: (1) utilization of brain cells in tissue culture as opposed to freshly prepared cell suspensions as a transplantation source, (2) prelabeling of fetal brain cells with inert, non-toxic tracer substances to allow subsequent (a) unequivocal identification of those cells as being fetally derived, and (b) anatomical and immunohistochemical identification of transplanted neurons, and (3) development of in vitro models for transplantation to allow physiological studies of connections formed between fetal neurons and host brain tissue . We examined the ability of brain cell suspensions derived from rat fetuses 15-17 gestational days old to accumulate and retain anatomic tracing substances, including Phaseolus vulgaris leucoagglutinin (PHA-L), rhodamine-labeled latex microspheres (RLM) and fluorogold (FG) . All tracers were rapidly accumulated by fetal brain cells, but only PHA-L and RLM were retained following implantation into adult hosts or in tissue culture in vitro . PHA-L-labeled fetal brain cells transplanted in vivo showed morphological characteristics similar to fetal neurons kept in tissue culture in vitro . RLM- or PHA-L-labeled fetal brain cells can be co-cultured with rat brain slices maintained in long-term roller culture . This in vitro system will allow identification and physiological or immunohistochemical study of interactions between fetally derived and host brain neurons. Vopr Med Khim, 1989 Mar-Apr, 35(2), 121 - 3 {Activity of lysosomal proteinases in the liver, spleen, thymus and peritoneal macrophages after immunization of mice with thymus-dependent and thymus-independent antigens}; Vasil'ev AV et al.; Mice of the CBAxC97B/6 strain were immunized with sheep erythrocytes at a dose of 0.5 ml containing 5% and 25% of the cell suspension and with Vi-antigen at doses of 2 micrograms/ml and 10 micrograms/ml, respectively . Sheep erythrocytes caused dose-dependent stimulation of cathepsin B, C and H in spleen, whereas cathepsin B was activated 3.1-3.6-fold after administration of Vi-antigen . Functional state of the lysosomal proteolytic system did not alter in thymus in response to sheep erythrocytes, while Vi-antigen activated distinctly thiol-dependent proteinases . In peritoneal macrophages administration of sheep erythrocytes led to 2-5-fold decrease in activity of all the lysosomal proteinases studied (cathepsins A, B, C, D, H and L), however Vi-antigen exhibited direct dose-dependent effect on activity of cathepsins A, B, D and L . The data obtained suggest that T-independent reactions of the immune system were realized via thiol-dependent lysosomal proteinases. Transplantation, 1989 Mar, 47(3), 449 - 50 Evidence that temporary complete occlusion of splenic vessels prevents massive embolization and sudden death associated with intrasplenic hepatocellular transplantation; Nieto JA et al.; It has been reported elsewhere that liver cell suspensions injected at several locations retain some proper hepatic functions, significantly improve the survival rate of rats with different models of acute fulminant hepatic injury, correct some congenital enzyme deficiency diseases, and improve liver function in cirrhotic animals . Among several locations, the splenic parenchyma has been shown to be the most suitable place for hepatocellular transplantation . Unfortunately, infusion of cells into the splenic pulp is not without risk . In fact, portal hypertension and hepatic embolizations have been described after intrasplenic transplantation of hepatocytes or pancreatic islets or fragments . In addition, pulmonary hepatocyte embolizations have been observed in rats with spontaneous (unpublished observations) or surgically induced portosystemic shunts . In this work, we evaluate the efficacy of temporary occlusion of splenic vessels to prevent hepatic and pulmonary embolizations after liver cell transplantation into the spleen in portal hypertension cirrhotic rats with portosystemic shunts. Clin Orthop, 1989 Mar, (240), 270 - 80 Osteogenic stem cells and the stromal system of bone and marrow; Beresford JN; According to current hypothesis, cells of the osteogenic lineage, which includes both osteoblasts and chondroblasts, are derived from a stromal stem cell in the postnatal organism . That there exist osteogenic precursors in association with the soft, fibrous tissue of the marrow stroma is well established . An osteogenic tissue comprised of cartilage and bone is formed when marrow or marrow cell suspensions are cultured in vivo within diffusion chambers . Bone with a functional marrow organ is formed when marrow or marrow cell suspensions are transplanted heterotopically, e.g., under the renal capsule . Cultures of marrow stromal fibroblasts are readily established in vitro from single-cell bone marrow suspensions . Such cultures do not demonstrate overt differentiation in an osteogenic direction in vitro . When transplanted in vivo, however, they differentiate to form cartilage and bone in diffusion chambers and bone with a functional marrow organ when transplanted heterotopically . Single-cell bone marrow suspensions can be cultured in vitro under conditions that facilitate the formation of stromal fibroblast colonies . Circumstantial evidence supports the conclusion that each colony is derived from a single initiating cell termed a colony-forming unit-fibroblastic (CFU-F) . A proportion of CFU-F demonstrates extensive proliferative potential both in vitro and in vivo . In vitro the extensive proliferative potential of a subset of CFU-F has been shown to be associated with a capacity for extensive self-renewal . On transplantation in vivo, the progeny of a proportion of CFU-F has been shown to be capable of proliferating and differentiating into all the stromal cell lines necessary for the formation of bone and reconstitution of the hematopoietic inductive microenvironment . These findings provide strong circumstantial evidence to support the hypothesis that there are stem cells present within the marrow stroma that are capable of giving rise to cells of a number of different lineages, including those of the osteogenic lineage (chondroblasts and osteoblasts). J Neurosurg, 1989 Mar, 70(3), 441 - 5 Implantation of dispersed cells into primate brain; Plunkett RJ et al.; Although several experimental therapies such as dopaminergic cell implantation in parkinsonian models and intratumoral placement of lymphokine-activated killer cells require intracerebral deposition of dispersed cell suspensions, a successful technique of needle implantation of cells into primate brain has not been demonstrated . The authors have sought to establish a stereotaxic technique to predictably deposit dispersed cells in primate brain . Human lymphocytes were cultured in recombinant interleukin-2, labeled with sodium 51 chromate (51Cr), and stereotaxically injected into the frontal white matter of six anesthetized rhesus monkeys . A 10-microliters aliquot of cell suspension (2 X 10(7) cells/ml) was deposited 16 mm deep to the dura at 5 microliters/min via Hamilton No . 22s or 26s needles . Five control aliquots were counted for each injection . Reflux out of the needle track was absorbed on gauze, and the recovered cells were counted . The animals were sacrificed 1 hour after implantation and the brain was removed and sectioned such that the cortex and white matter along the needle track were separate . The tissue sections were then counted . Recovery was expressed as the percentage of total injected radioactivity (cpm) that was present in each brain section . Two additional injected hemispheres were processed for autoradiography and histological study . Cell recovery in the brain (mean +/- standard deviation) was 87.2% +/- 13.9% (3.3% +/- 4.9% in cortex and 83.9% +/- 15.9% in white matter) . The autoradiograms and histological examination showed a dense accumulation of radioactivity (cells) at the target site and minimal radioactivity (cells) in the needle track . Accurate intracerebral deposition of dispersed cells in primates was achieved with the technique described . This knowledge permits reliable stereotaxic implantation of cells into the brains of nonhuman primates and humans for investigation and therapy. Zh Obshch Biol, 1989 Mar-Apr, 50(2), 149 - 57 {Experimental embryologic, biochemical and molecular biology approaches to the identification of embryonic inducers}; Mikhailov AT; Problems of the mechanisms of embryonic induction in vertebrate development have been considered on the basis of author's experimental data . Though several polypeptide factors with certain inducing activity have been identified recently, molecular genetic mechanisms of their effect on embryonic target cells remains largely unclear . One of possible causes of very slow progress in this area of developmental biology is an inadequate system of biotesting of inducers at tissue level (ectoderm of early amphibian gastrulae) using histological criteria . A necessity for carrying out similar studies on cellular level and estimating effect of inducers using immunochemical and molecular biological methods has been postulated . Methods allowing to carry out biotesting of inducers on cell suspension or aggregate of a one type of embryonic cells have been proposed . New approaches, combining the methods of experimental embryology and molecular biology, to studies of embryonic inducers, receptors, and their mRNA, have been analyzed. Eur Respir J, 1989 Mar, 2(3), 202 - 9 Increased generation of the arachidonic metabolites LTB4 and 5-HETE by human alveolar macrophages in patients with asthma: effect in vitro of nedocromil sodium; Damon M et al.; Alveolar macrophages (AM) are the principal resident phagocytes in the human lung, and play a major role in local defence against environmental agents . It is now known that during asthma these cells take part in the amplification of the inflammatory mechanism . It has been demonstrated in vitro that they can be activated to generate leukotriene B4 (LTB4) and 5-hydroxyeicosatetraenoic acid (5-HETE), mediators with potent pharmacological properties . These two arachidonic metabolites were identified and quantified by reversed phase high performance liquid chromatography (HPLC) performed in cell suspensions, and in cell free supernatants . AM from asthmatics, after stimulation by the calcium ionophore A23187 or opsonized zymosan, released significantly (p less than 0.05) more LTB4 than those from healthy subjects . The increase in LTB4 release could be evidence for in vivo activation . On the other hand, the levels of 5-HETE in the AM from asthmatics were significantly (p less than 0.03) higher than those in cells from healthy subjects . This intracellular increase could be correlated with a greater migratory ability of these inflammatory macrophages, as observed for eosinophils . The clinical efficacy of nedocromil sodium may be partly related to the decreases in LTB4 releasability and intracellular 5-HETE levels observed only in AM from asthmatic patients. Am J Physiol, 1989 Mar, 256(3 Pt 1), C598 - 607 Increase vs . decrease of calcium uptake by isolated heart cells induced by H2O2 vs . HOCl; Kaminishi T et al.; Adult rat heart myocytes were labeled rapidly with exogenous {45Ca2+} . Addition of 2.5 mM H2O2 to the heart cell suspension raised the content of rapidly exchangeable intracellular Ca2+ twofold, whereas addition of 1-30 mM HOCl decreased the Ca2+ content . The H2O2-induced increase in Ca2+ content was dependent on the medium Na+, pH, and temperature but was not significantly affected by addition of verapamil, diltiazem, amiloride, or 3-aminobenzamide . The {3H}ouabain binding to myocytes was suppressed by H2O2, whereas the Ca2+ efflux from myocytes was not influenced . An uncoupler, carbonyl cyanide m-chlorophenylhydrazone, reduced Ca2+ content, implying that the H2O2-induced change in Ca2+ content was not directly related to ATP depletion . On the other hand, the H2O2-induced Ca2+ accumulation in myocytes was prevented by deferoxamine or o-phenanthroline . These results suggest that H2O2 inhibited Na+-K+-ATPase, resulting in an increase in intracellular Na+ concentration and stimulation of sarcolemmal Na+-Ca2+ exchange activity, which caused a transient net Ca2+ influx into myocytes . By contrast, HOCl decreased the Ca2+ content of the rapidly exchangeable pool below control levels and this action of HOCl was antagonized by 1,4-dithiothreitol . HOCl accelerated Ca2+ efflux from myocytes . Ca2+ uptake and Ca2+-ATPase of the isolated sarcoplasmic reticular (SR) fraction were highly sensitive to the action of HOCl . Ca2+ uptake by intracellular sites, studied with myocytes permeabilized with digitonin, was inhibited by both H2O2 and HOCl . Thus these results suggest that HOCl inhibits the SR Ca2+ pump, resulting in the observed acceleration of Ca2+ efflux from and decline in Ca2+ content of myocytes. Hum Cell, 1989 Mar, 2(1), 70 - 3 {A significance of dual parameter flow cytometric DNA analysis using the anti-keratin antibody}; Ishikawa H et al.; Flow cytometric DNA analysis using the anti-cytokeratin antibody was carried out in order to estimate more reliable measurement in single cell suspension obtained from solid tumors . It was difficult to detect a DNA aneuploidy with DI of 2.0 by one parameter analysis of DNA . Whereas it could be detected easily by using dual parameter analysis of cytokeratin and DNA . And also, the pattern of DNA multiploidy could be selected for cytokeratin positive cell population by gate analysis. Biol Reprod, 1989 Mar, 40(3), 466 - 74 Effects of lymphokines and immune complexes on murine placental cell growth in vitro; Armstrong DT et al.; Isolated murine placental cells obtained at Day 16 of allogeneic gestation (C3H x DBA/2J) were cultured for 3 days alone or in coculture with irradiated mouse splenocytes at the end of which 3H-thymidine was added for an additional 18-h culture to assess cell proliferation . Placental cell proliferation was significantly enhanced at spleen cell:placental cell ratios of 10:1 and 25:1 above that observed in the absence of added spleen cells . The stimulatory effect of irradiated allogeneic (C3H plus Balb/cJ) spleen cell cultures was significantly greater (approximately 2-fold) than that of isogeneic spleen cells (C3H alone) . Conditioned medium from murine spleen cells cultured with concanavalin A (ConA) to induce lymphokine production had dose-dependent inhibitory effects on proliferation when added to placental cell cultures over a range of concentrations from 10 to 40% (vol:vol) . Addition of pseudo "immune complexes" in the form of heat-aggregated human gamma globulin (AHGG) to culture medium failed to alter placental cell proliferation over a range of concentrations from 2 to 200 micrograms/ml either in the absence or presence of ConA-conditioned medium . In contrast to late-gestational stage placental cells, cell suspensions obtained from Days 8-9 murine ectoplacental cone (EPC) outgrowths, or from earlier stage placentas (Days 12-14) responded to low concentrations of conditioned medium from ConA-stimulated splenocytes with increased proliferation . The effect was less impressive on placental cells at gestational ages later than 12 days than on earlier stage preparations . On all placental cell suspensions tested, as well as EPC cells, a clear-cut inhibition of growth was observed at high doses of conditioned medium.(ABSTRACT TRUNCATED AT 250 WORDS) Clin Exp Metastasis, 1989 Mar-Apr, 7(2), 187 - 99 Tumor cell settling and early invasion of the peritoneum; van de Molengraft F et al.; A Sewall Wright strain-2 guinea pig model producing malignant ascites after injection of a diethylnitrosamine-induced hepatocellular carcinoma cell suspension (Line-10) was used to demonstrate the multilayered settling of tumor cells on the peritoneal surface, frequently followed by the formation of papillary projections and the early invasion in a proliferating submesothelial tissue . At the border of tumor cells and the desmoplastic tissue the malignant cells changed their shape and generally two categories were recognized . Often multilayering, atypical flat cells covered the stromal tissue, while mostly rounded ones invaded using their branched penetration processes, being devoid of cationized ferritin, which was only present on the luminal sides of all cellular elements . Flattened malignant cells, penetrating processes and invading cells lost their microvillous surface pattern . The infiltrating cells were often only detectable with the monoclonal antibody 10 TL 40 and the anti-cytokeratin OV TL 12-5, demonstrating the need for immunohistochemistry in diagnosing solitary invading malignant cells in light microscopy . It appeared that still numerous mesothelial cells were found scattered deeply within the desmoplastic tissue . These former lining cells were identified by their junctions and the presence of remnants of basal lamina as well as by their microvillous 5'-nucleotidase activity. J Immunol Methods, 1989 Feb 24, 117(2), 275 - 84 Detection and isolation of antigen-specific B cells by the fluorescence activated cell sorter (FACS); Hoven MY et al.; A method is described for the isolation of antigen-specific B cells from immunized and subsequently boosted mice . Antigen-specific B cells were stained by incubation with fluorescein isothiocyanate (FITC)-labelled antigen and then detected and isolated in a fluorescence activated cell sorter (FACS) . Ovalbumin (OVA) and Helix pomatia haemocyanin (HPH) were used as antigens in this procedure, yielding relative amounts of antigen-FITC-binding lymphocytes of 0.9 +/- 0.4% and 3.5 +/- 3.1% . The FITC-positive cells were visible as distinct cell populations in the FACS-generated histograms . All antigen-FITC-binding cells were B cells, as shown by double staining with phycoerythrin-conjugated anti-mouse Ig In addition, as tested in a spot-ELISA, the sorted, antigen-FITC-binding cell population contained almost the entire population of antigen-specific antibody-producing B cells . However, sorting had a negative influence on the antibody production capability of the sorted cells . Through washing of isolated spleen cells in the procedure before labelling with antigen-FITC proved to be essential for the specific detection of antigen-specific B cells, since staining without prior washing resulted in antigen-FITC binding to all B cells . This 'nonspecific' staining phenomenon was caused by the presence of antibodies, specific for the immunizing/boosting antigen, which were also present in the spleen cell suspension . These antibodies formed immune complexes with antigen-FITC and bound to Fc receptors present on all B cells, interfering in this way with any specific binding of antigen-FITC to sIg on the B cells. Neurosci Lett, 1989 Feb 13, 97(1-2), 51 - 6 The rabbit retina: a suitable mammalian tissue for obtaining astroglia-free Müller cell cultures; Scherer J et al.; Monolayer cultures were prepared from two distinct parts of early postnatal rabbit retinae . Cell suspensions obtained from the developing medullary ray (MR) region contained neurons, Muller (glial) cells, and astrocytes, cells obtained from the remainder (peripheral) part of the retina contained neurons and Muller cells, but no astrocytes . Muller cells lack glial fibrillary acidic protein (GFAP) immunolabeling in situ but some of them acquire faint GFAP labeling in both types of cultures . Strongly GFAP-labeled cells, most likely astrocytes, were seen in MR cultures only . We propose that the periphery of the rabbit retina is ideal for obtaining astroglia-free Muller cell cultures to study their functional properties in vitro. Clin Sci (Lond), 1989 Feb, 76(2), 183 - 7 Human whole-blood granulocyte aggregation in vitro; Fisher TC et al.; 1 . Aggregation assays are a commonly used technique for the study of granulocyte activation . These studies are usually performed using a pure cell suspension in buffer . This necessitates a separation procedure which is time-consuming and may modify the function of the cells . Interaction between different cell types is precluded . 2 . To avoid these disadvantages a method was developed which quantifies granulocyte aggregation in whole blood . Samples drawn from an incubated vessel before and after the addition of a chemotactic stimulus were fixed with formaldehyde to prevent disaggregation . Erythrocytes were then removed by chemical lysis and using an electronic cell-sizing device the number of single cells and aggregates could then be easily measured . 3 . Results from a group of volunteers showed a rapid and reversible response to a chemotactic tripeptide, with a fall in single granulocyte count and the appearance of doublets and triplets . Lymphocytes were unaffected . Intra-assay reproducibility was better than +/- 5% . 4 . Using this assay, a significant elevation in aggregability was observed in blood from patients after acute myocardial infarction . 5 . This novel technique, by avoiding the separation step, is faster, simpler and more physiological than previous methods, and as such is useful for both assays of drug action in vitro and the study of cell activation in disease states. Am J Physiol, 1989 Feb, 256(2 Pt 1), C252 - 9 Regulatory volume decrease by cultured renal cells; Knoblauch C et al.; Volume regulatory responses of OK cells (a continuous epithelioid cell line from opossum kidney) are examined by electronic cell sizing and measurements of intracellular pH in cell suspensions . In response to a 40% reduction in osmolality, the cells swell and then subsequently shrink toward their starting volume . This regulatory volume decrease (RVD) is reduced by replacement of Cl- in the medium with acetate . Replacement of Cl- with NO3- accelerates the RVD . The RVD response is inhibited by 1 mM quinine or 100 microM 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) in the medium . The inhibitory effect of 100 microM DIDS (but not 1 mM quinine) is altered by replacement of Cl- by NO3- in the medium . Hypotonic challenge does not induce a DIDS-sensitive net flux of acid-base equivalents . Addition of (9 microM) valinomycin also inhibits the RVD response . It is suggested that the RVD response of OK cells involves activation of separate K+ and Cl- channels. Exp Hematol, 1989 Feb, 17(2), 171 - 6 The concentration and resolution of primitive hemopoietic cells from normal mouse bone marrow by negative selection using monoclonal antibodies and Dynabead monodisperse magnetic microspheres; Bertoncello I et al.; High proliferative potential colony-forming cells (HPP-CFC) detected in clonal agar culture in the presence of the combined stimulus of colony-stimulating factor 1 (CSF-1) + interleukin 3 (IL-3) + interleukin 1 alpha (IL-1 alpha) are closely related to developmentally early progenitor cells capable of reconstituting the hemopoietic system of lethally irradiated mice following transplantation . Flow cytometric analysis and sorting of normal, unperturbed bone marrow has shown that HPP-CFC are B220- and 7/4-, whereas the committed progenitors of the macrophage lineage responsive to CSF-1 alone (CSFCSF-1) are B220- and 7/4+ . Negative immunomagnetic selection using an anti-7/4, anti-B220 antibody cocktail and second-antibody-coupled Dynabead microspheres to replace flow cytometry results in the highly reproducible and specific enrichment of HPP-CFC, and simultaneous resolution of HPP-CFC from CFCCSF-1 . The tenfold enrichment of HPP-CFC compared with unfractionated bone marrow cell suspensions was comparable to that obtained by fluorescence-activated cell sorting . Enrichment was achieved with negligible loss of HPP-CFC at the immunomagnetic bead selection step, and 65% of HPP-CFC were recovered . The method is rapid, highly reproducible, and efficient, and has wide application to the separation of rare hemopoietic cells from normal bone marrow. Cancer Res, 1989 Feb 1, 49(3), 528 - 32 Antitumor activity of murine neutrophils demonstrated by cytometric analysis; Ackermann MF et al.; The cytostatic and cytolytic activities of activated polymorphonuclear neutrophils (PMNs) against YAC-1 lymphoma target cells were examined using multiparameter flow cytometric analysis . PMNs were resolved from tumor cells by 90 degrees light scatter . The number of surviving tumor cells was determined by adding a known concentration of fluorescent latex particles to the fixed cell suspension immediately prior to analysis and counting the particles simultaneously with the cells . Cell cycle progression of the YAC-1 target was studied by dual parameter analysis of DNA content and bromodeoxyuridine incorporation into tumor cell DNA either prior to or following addition of PMNs . The results indicate that activated PMNs effectively kill tumor cells within the first 24 h of coculture . However, between 24 and 48 h, tumor cells which escape destruction resume growth and eventually reach a growth rate greater than control cells. Development, 1989 Feb, 105(2), 379 - 85 Cloned mouse melanocyte lines carrying the germline mutations albino and brown: complementation in culture; Bennett DC et al.; We have established two new immortal lines of mouse melanocytes, melan-b and melan-c, from mice homozygous for the brown (b) and albino (c) mutations respectively . Both lines were derived through differentiation in vitro of embryonic epidermal melanoblasts . The brown melanocytes are visibly brown by light microscopy, and centrifuged cell suspensions form brown pellets . The albino melanocytes form white pellets and contain abundant unpigmented premelanosomes as shown by transmission electron microscopy . Like normal, non-immortal melanocytes and like the immortal black melanocyte line melan-a, both lines show little or no growth in a standard, serum-supplemented medium, but proliferate well in the presence of 12-o-tetradecanoyl phorbol-13-acetate (TPA) . Sustained growth of the albino cells also requires either keratinocyte feeder cells or 2-mercaptoethanol (2-ME) . The modal chromosome numbers are 39 for melan-b and 40 (diploid) for melan-c . Neither line is tumorigenic in nude mice . Heterokaryons between the two lines can be constructed and form wild-type, black pigment . Melanocyte lines can now be reproducibly generated from mice of different strains, and provide tools for molecular studies of germline coat-colour mutations . These two lines provide elegant means to study the developmentally controlled expression of the two complementary genes, B and C, with black melanin pigment as a readily detectable natural marker. Scand J Immunol, 1989 Feb, 29(2), 193 - 201 Migration pattern of lymphocyte subsets in the normal rat and the influence of splenic tissue; Westermann J et al.; Lymphocyte subsets leave the blood and appear in the thoracic duct of normal rats at different rates . The aim of the present study was to investigate their migration pattern through blood, spleen, bone marrow, mesenteric lymph nodes, and Peyer's patches in normal Lewis rats and to study the role of the spleen using splenectomized and spleen-transplanted animals . Fluorescein isothiocyanate (FITC)-labelled thoracic duct lymphocytes (TDL) were injected intravenously into rats and after 15 min, 1, 6, and 24 h the percentages of B, T, T helper (TH) and T-cytotoxic/suppressor (TC/S) lymphocytes in the FITC+ cells were determined in cell suspensions by means of monoclonal antibodies . B and T lymphocytes are preferentially localized in different organs, e.g . B cells in Peyer's patches and T cells in mesenteric lymph nodes . The migration of TH lymphocytes differed from that of TC/S lymphocytes in all the organs investigated . In the late phase after injection the migration of B and TH lymphocytes was influenced by the spleen, since after splenectomy the number of injected B lymphocytes increased and that of TH lymphocytes decreased in all organs investigated except the bone marrow . Splenic autotransplantation could not normalize the disturbed migration. J Immunol, 1989 Feb 1, 142(3), 1036 - 45 Effect of LAK cells against three-dimensional tumor tissue . In vitro study using multi-cellular human glioma spheroids as targets; Jaaskelainen J et al.; The anti-tumor mechanisms of local LAK cell therapy are difficult to study in vivo . We describe a method to study in vitro the action of LAK cells against three-dimensional tumor tissue . Spherical cell aggregates (spheroids) grown from human glioma cell lines H-2 and U-251 were labeled with 51Cr and then incubated for up to 24 h with LAK cells . After the incubation, most spheroids were still macroscopically identifiable, and the measured reduction of volume did not correlate to the extent of damage . LAK cells infiltrated into spheroid tissue slowly as a frontier which explains why the specific 51Cr release was clearly slower from spheroids than corresponding single cell suspensions . The infiltrated area was at 1 to 2 h very thin but by 8 to 12 h consisted already of several cell layers . Most H-2 spheroids became totally infiltrated by 16 to 24 h whereas in U-251 spheroids the infiltration usually remained peripheral . In accordance with the different extent of infiltration, H-2 spheroids were clearly more sensitive to LAK cells than U-251 spheroids: at E/T ratio 10:1 the mean specific 51Cr release by 24 h was 63 and 36%, respectively . A single exposure to LAK cells released 51Cr from H-2 spheroids approximately 12 h but over 24 h from U-251 spheroids . The spheroid model can be used to study the infiltrative capacity and cytotoxicity of LAK cells against three-dimensional tumor tissue, and the method may help to find an optimal mode of local LAK cell therapy, i.e., proper combination of lymphokines and LAK cells, and proper timing of their administration. Tsitologiia, 1989 Feb, 31(2), 251 - 3 {A method of shaking-blotting--a simple and reliable means for obtaining direct chromosomal preparations from chorionic biopsies}; Baranov VS; The method proposed is based on a gradual fixation, and short-term hydration before softening and on a new technique of chromosome preparation . The latter is based on the sample softening in 60% acetic acid directly on the slide, its gentle shaking and spot-blotting, a careful spreading of the cell suspension on slide surface avoiding the usage of micropipets and other handlings causing metaphase plate breakage . The method provides a highly efficient karyotyping of human embryos within the 7-12th weeks of gestation. Anal Quant Cytol Histol, 1989 Feb, 11(1), 67 - 71 Comparison of flow cytometric data obtained using fresh and paraffin-embedded lymphoid tissue; Grace J et al.; Flow cytometric (FCM) DNA analysis was carried out on 24 lymph nodes: 13 from benign reactive hyperplasias and 11 from non-Hodgkin's lymphomas . FCM was performed on two types of samples: (1) fresh cell suspensions and (2) suspensions prepared from formalin-fixed, paraffin-embedded sections . FCM of fresh samples detected aneuploidy in 23 of the 24 cases while FCM of paraffin-embedded samples detected aneuploidy in only 6 of the 24 cases . Those six cases were lymphomas considered histologically as having a poor prognosis . Only one case, a lymphoma, was euploid with both methods . The coefficients of variance determined in each case for both methods were found to be within "normal ranges," but were greater in the paraffin-embedded specimens . The results suggest that FCM DNA analysis of formalin-fixed, paraffin-embedded sections does not have as great a resolution capacity as does analysis of fresh cell suspensions, since the former failed to detect cell populations that had a small degree of aneuploidy (close to the 2n population). Artif Organs, 1989 Feb, 13(1), 4 - 20 The physics of continuous flow centrifugal cell separation; Brown RI; The governing equations defining the separation of blood in continuous flow centrifuges are derived using an empirical model for the viscosity of blood . The effects of fluid shear on the separation process are addressed and further models are developed to permit estimations of shear rate during centrifugation . Simplified predictive equations for species specific separations are developed . Contributions due to shear enhanced diffusion are addressed and found to be negligible at the discontinuous interface between cells and plasma . Experimental results from an investigational centrifuge are presented and compared with theoretical predictions . The role of rouleaux formation in conventional centrifuges is discussed and known centrifugal separation characteristics are explained . The viscosity of blood is related to that for suspensions of rigid particles and an equation for the hydraulic permeability of red blood cell suspensions is derived. Eur J Cell Biol, 1989 Feb, 48(1), 116 - 20 The hepatic asialoglycoprotein receptor selectively binds to some endogenous tissues; Treichel U et al.; The hepatic asialoglycoprotein receptor (ASGP-R) was isolated from various rat tissues or freshly prepared single cell suspensions and tested for the binding to endogenous tissues or specific cell types by indirect immunofluorescence . Inhibition with N-acetyl-D-galactosamine demonstrated specificity of binding . ASGP-R binds to mesodermal tissues and to selected cells of the majority of glandular tissues but not to lining epithelia . ASGP-R stains heart muscle but not skeletal muscle . In addition, ASGP-R stains spleen cells (52%), bone marrow cells (55%), thymocytes (62%), and a fraction of peripheral blood lymphocytes (29%), which was identified as B-lymphocytes . Five different rat tumors also showed binding of ASGP-R . The binding pattern and staining intensity of peanut agglutinin and soybean agglutinin were strikingly different although the binding specificity of these lectins is related to the ASPG-R . It is concluded that considerable numbers of endogenous binding sites for the hepatic ASGP-R exist in normal tissue, even on cells which pass the liver on circulation. Plast Reconstr Surg, 1989 Feb, 83(2), 368 - 81 Historical review and present status of free fat graft autotransplantation in plastic and reconstructive surgery; Billings E Jr et al.; Free fat graft autotransplantation for soft-tissue replacement has been a neglected subject in recent years . In a review of the literature, investigations of the various uses of free fat autotransplantation in animals and humans provide an understanding of the problems associated with the use of fat as a free graft . Results of free fat autotransplantation were found to be quite unpredictable, with wide variations in the resulting bulk of the graft . Microscopic studies of this behavior led to controversy as to whether the graft ultimately was made of surviving graft adipocytes (cell survival theory) or host adipocytes (host replacement theory) . Studies revealed a "fibroblast-like" mesenchymal cell within adipose tissue that was believed to be an immature adipocyte precursor or preadipocyte . Further characterization of the preadipocyte and its complete differentiation was accomplished using tissue-culture techniques . These investigations provide evidence of the dynamic nature of adipose tissue that strongly supports the cell survival theory and gives explanation to the unpredictable behavior of free fat autografts . Many conditions treated by plastic surgeons require soft-tissue augmentation . Autogenous adipose tissue is the most appropriate and natural replacement material . With new culturing techniques, preadipocytes in a single cell suspension may provide an injectable soft-tissue replacement . This subject appears ripe for investigation. Sheng Li Xue Bao, 1989 Feb, 41(1), 70 - 5 {The content of tyrosine in rat luteal cell and the changes caused by hCG, cAMP and progesterone}; Zhang Q et al.; The ovaries taken from the immature female rats primed with PMSG-hCG were digested with collagenase-DNAase solution to obtain the luteal cell suspensions . Luteal cells were then incubated with different doses of hCG, cAMP or progesterone for 1.5 hours . The contents of tyrosine in luteal cell suspensions were determined by thin layer chromatogram using dual-wavelength chromatogram scanner . It was found that the content of tyrosine in rat luteal cell suspensions was 1.41 + 0.24 nmol/L/10(6) cells after one hour incubation . hCG, cAMP and progesterone all could significantly increase the content of tyrosine in the suspensions, suggesting the release of "endogenous tyrosine" . The increase of tyrosine was not due to increased transformation of phenylalanine, the precursor of tyrosine, and increased protein synthesis, because both phenylalanine and cycloheximide failed to influence such increase. Eur J Biochem, 1989 Feb 1, 179(2), 469 - 72 Proton translocation coupled to the oxidation of carbon monoxide to CO2 and H2 in Methanosarcina barkeri; Bott M et al.; Cell suspensions of acetate-grown Methanosarcina barkeri mediate the conversion of CO and H2O to CO2 and H2 . The reaction is coupled with the phosphorylation of ADP . Evidence is presented that CO oxidation by the cells is associated with the transient acidification of the suspension medium . Up to 2 mol vectorial protons were measured/mol CO oxidized when the transmembrane electrical gradient was kept low by the addition of valinomycin (20 nmol/mg protein) and KCl (200 mM) or of KSCN (50 mM) . No transient acidification was observed in the presence of the protonophore tetrachlorosalicylanilide which stimulated rather than inhibited CO oxidation . Proton extrusion remained unaltered when the proton-translocating ATPase was specifically inhibited by dicyclohexylcarbodiimide . The latter finding indicates that proton translocation is associated with CO conversion to CO2 and H2 rather than with ATP hydrolysis in the cells . The data substantiate that the coupling of CO oxidation with ADP phosphorylation in M . barkeri occurs via a chemiosmotic mechanism. Immunology, 1989 Feb, 66(2), 190 - 5 Effects on rat T-helper cell proliferation by syngeneic epidermal cells exposed to IFN-gamma in vivo; Skoglund C et al.; In several conditions in the skin, characterized by T-cell infiltration, keratinocytes are induced to synthesize and express class II transplantation antigens . The biological significance of this induced expression is still not understood . In this study, class II antigens were induced on rat ear keratinocytes by local intradermal injections into the ear of rat recombinant interferon-gamma (IFN-gamma) . Epidermal cell suspensions prepared from these ears contained more than 50% class II-expressing cells, as judged by immunocytochemistry, compared with less than 5% in untreated epidermis . When comparing the capacity of these to different epidermal cell populations to stimulate a syngeneic PPD-specific T-helper cell line, it was found that IFN-gamma-exposed epidermal cells induced a lower T-cell response to PPD than did normal epidermal cells . This discrepancy could not be explained by either an infiltration of inflammatory cells into the epidermis of IFN-gamma-treated ears or by a difference in interleukin-1 production as determined in culture supernatants . The addition of indomethacin to cultures with IFN-gamma-exposed epidermal cells restored the T-cell response to PPD to that of normal epidermal cells, suggesting an inhibitory effect of prostaglandins . Our data indicate that epidermal cells exposed to IFN-gamma in vivo can suppress an antigen-specific T-cell proliferation. Int J Radiat Oncol Biol Phys, 1989 Feb, 16(2), 415 - 35 Effects of recombinant growth factors on radiation survival of human bone marrow progenitor cells; Uckun FM et al.; The purpose of this study was to evaluate the individual radioprotective effects of 4 distinct purified recombinant human hematopoietic growth factors, namely recombinant human granulocyte-macrophage colony stimulating factor (rGM-CSF), recombinant human granulocyte colony stimulating factor (rG-CSF), recombinant human interleukin 1 (rIL-1), and recombinant human interleukin 2 (rIL-2) on human myeloid (CFU-GM) and erythroid (BFU-E) bone marrow progenitor cells . We demonstrate that (a) preconditioning with rGM-CSF, rG-CSF, or rIL-1 enables CFU-GM to repair sublethal radiation damage and renders CFU-GM less radiosensitive, (b) preconditioning with rGM-CSF or rIL-1 enables BFU-E to repair sublethal radiation damage, and (c) preconditioning with rIL-2 does not increase the radiation survival of CFU-GM or BFU-E . The effects of recombinant growth factors, in particular rGM-CSF, on the radiation damage repair, radiosensitivity, and proliferative activity of bone marrow progenitor cells resulted in a substantial increase in the mean numbers of progenitor cell-derived hematopoietic colonies in irradiated marrow samples . The effects of rGM-CSF on the radiation response of CFU-GM and BFU-E, and the effects of rG-CSF as well as rIL-1 on the radiation response of CFU-GM did not appear to require the presence of T-cells/T-cell precursors, NK-cells, B-cells/B-cell precursors, monocytes, macrophages, MY8 antigen positive non-CFU-GM myeloblasts, promyelocytes, myelocytes, metamyelocytes, granulocytes, or glycophorin A positive erythroid cells since virtually identical results were obtained with unsorted marrow samples or highly purified fluorescence activated cell sorter (FACS) isolated progenitor cell suspensions . To our knowledge, this report represents the first study on recombinant human growth factor-induced modulation of the radiation responses of normal human bone marrow progenitor cells. Inflammation, 1989 Feb, 13(1), 103 - 23 Guinea pig lung cells . Method of isolation and partial purification, identification, ultrastructure, and cell count; Pele JP et al.; Guinea pig lung cells (over 700 x 10(6) cells/lung) were obtained following gentle digestion of lung tissues with a solution of protease type VII (50 micrograms/ml) . The viability of these cells was over 86% as estimated by the trypan blue exclusion technique . The cell suspensions were elutriated into eight fractions, which were characterized by selected staining techniques (Alcian blue, esterase, and Papanicolaou) and by electron microscopy . Differential cell counts were done to establish the percentages of each type of cells in the overall population . Electron microscopy analyses of the cell populations have allowed the identification of most of the various isolated cell types and showed that the cellular organelles and ultrastructures were well preserved . These cell populations will be used for characterizing lung immunologic, metabolic, and endocrine functions, as well as for studying cell interactions. Cell Biophys, 1989 Feb, 14(1), 1 - 16 Energetics of cell-cell and cell-biopolymer interactions; van Oss CJ; The energy vs distance balance of cell suspensions (in the presence and in the absence of extracellular biopolymer solutions) is studied, not only in the light of the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory (which considered just the electrostatic (EL) and Lifshitz-van der Waals (LW) interactions), but also by taking electron-acceptor/electron-donor, or Lewis acid-base (AB) and osmotic (OS) interactions into account . Since cell surfaces, as well as many biopolymers tend to have strong monopolar electron-donor properties, they are able to engage in a strong mutual AB repulsion when immersed in a polar liquid such as water . The effects of that repulsion have been observed earlier in the guise of hydration pressure . The AB repulsion is, at close range, typically one or two orders of magnitude stronger than the EL repulsion, but its rate of decay is much steeper . In most cases, AB interactions are quantitatively the dominant factor in cell stability (when repulsive) and in "hydrophobic interactions" (when attractive) . OS interactions exerted by extracellularly dissolved biopolymers are weak, but their rate of decay is very gradual, so OS repulsions engendered by biopolymer solutions may be of importance in certain long-range interactions . OS interactions exerted by biopolymers attached to cells or particles (e.g., by glycocalix glycoproteins), are very short-ranged and usually are negligibly small in comparison with the other interaction forces, in aqueous media. Gynecol Oncol, 1989 Feb, 32(2), 203 - 14 Characterization of a hormone-producing ovarian carcinoma cell line; Poels LG et al.; An ovarian carcinoma cell line (OTN 11) was produced from the ascitic fluid of a patient with a moderately to well differentiated papilliferous cystadenocarcinoma of the ovary . The cell line was characterized using electron microscopy karyotyping, immunohistochemical techniques with monoclonal antibodies against keratins as epithelial markers, and the monoclonal antibodies OV-TL 3 and OC 125 as ovarian carcinoma markers . These techniques revealed the epithelial and adenocarcinomatous nature of the cell line and the presence of ovarian carcinoma-related surface markers . The adenocarcinomatous nature of the cell line also became apparent after heterotransplantation of cell suspensions into nude mice and nude rats, in which adenomatous tumor structures were formed . These xenografts had the same ultrastructural and immunohistochemical properties as the cell line . Despite the adenocarcinomatous character of the tumor the cultured cells release estradiol into the culture medium . We may conclude that OTN 11 is an ovarian carcinoma cell line which has retained highly differentiated functions, such as the production of an ovarian hormone. Experientia, 1989 Jan 15, 45(1), 96 - 8 Presence of benzodiazepine binding sites (receptors) and amplification thereof by imprinting in Tetrahymena; Csaba G et al.; Live Tetrahymena cells bound 3H-diazepam specifically, as demonstrated by autoradiographic evidence of displacement of about 25% of labeled diazepam in the presence of a 1000-fold amount of cold diazepam . The 3H-diazepam bound to membrane preparations isolated from untreated (control) cells was not displaced by cold diazepam, whereas cells involved in primary interaction (imprinting) with diazepam showed amplification and specificity of diazepam binding in both in vivo (cell suspension) and in vitro (pellicle) systems, as well as displacement of bound label in the presence of 1000-fold cold diazepam . It appears that diazepam induced imprinting and, consequently, also the formation of specific receptors in Tetrahymena. J Biol Chem, 1989 Jan 15, 264(2), 973 - 80 Suppression of insulin release by galanin and somatostatin is mediated by a G-protein . An effect involving repolarization and reduction in cytoplasmic free Ca2+ concentration; Nilsson T et al.; The effects of galanin and somatostatin on insulin release, membrane potential, and cytoplasmic free Ca2+ concentration {( Ca2+}i) were investigated using beta-cells isolated from obese hyperglycemic mice . Whereas insulin release was measured in a column perifusion system, membrane potential and {Ca2+}i were measured with the fluorescent indicators bisoxonol (bis-(1,3-diethylthiobarbiturate)trimethineoxonol) and quin 2, in cell suspensions in a cuvette . Galanin (16 nM) and somatostatin (400 nM) suppressed glucose-stimulated insulin release in parallel to promoting repolarization and a reduction in {Ca2+}i . The reduction in {Ca2+}i comprised an initial nadir followed by a slow rise and the establishment of a new steady state level . The slow rise in {Ca2+}i was abolished by 50 microM D-600, a blocker of voltage-activated Ca2+ channels . Both peptides suppressed insulin release even when {Ca2+}i was raised by 25 mM K+ . Under these conditions the inhibition of insulin release was partly reversed by an increase in the glucose concentration . Addition of 5 mM Ca2+ to a cell suspension, incubated in the presence of 20 mM glucose and either galanin, somatostatin, or the alpha 2-adrenergic agonist clonidine (10 nM), induced oscillations in {Ca2+}i, this effect disappearing subsequent to the addition of D-600 . The effects of galanin, somatostatin, and clonidine on {Ca2+}i were abolished in beta-cells treated with pertussis toxin . In accordance with measurements of {Ca2+}i, treatment with pertussis toxin reversed the inhibitory effect of galanin on insulin release . The inhibitory action of galanin and somatostatin on insulin release is probably accounted for by not only a repolarization-induced reduction in {Ca2+}i and a decreased sensitivity of the secretory machinery to Ca2+, but also by a direct interaction with the exocytotic process . It is proposed that these effects are mediated by a pertussis toxin-sensitive GTP-binding protein. Brain Res, 1989 Jan 9, 476(2), 345 - 50 Minimal connectivity between six month neostriatal transplants and the host substantia nigra; McAllister JP 2nd et al.; The present study sought to determine if axonal connectivity is established between 6-month-old neostriatal transplants and the host substantia nigra . Cell suspensions of fetal neostriatum were transplanted into the adult rat neostriatum lesioned previously by kainic acid . Horseradish peroxidase injections into the ipsilateral ventral midbrain labelled the lesion site and the intact neostriatum extensively, but no appreciable anterograde or retrograde label was found within the graft . These results demonstrate a paucity of connectivity between neostriatal grafts and the host brain at a time when other investigators have described transplant-mediated recovery of function. Avian Dis, 1989 Jan-Mar, 33(1), 163 - 7 Separation of avian heterophils from blood using Ficoll-Hypaque discontinuous gradients; Andreasen CB et al.; Rapid separation of avian heterophils from anticoagulated whole blood was achieved using Ficoll-Hypaque discontinuous gradients . An average of 14.4% of blood heterophils was harvested with a mean purity exceeding 99% . Heterophil viability, as determined by trypan blue dye exclusion, averaged 99.8% . The integrity of isolated heterophils was evaluated by cytochemical staining and ultrastructural examination . Cytochemical staining reactions of heterophils in whole blood and of isolated cell suspensions were similar . No ultrastructural abnormalities were observed . Using this procedure, viable intact heterophils were rapidly isolated from blood with an acceptable cell yield and purity for cell function studies. Radiol Med (Torino), 1989 Jan-Feb, 77(1-2), 94 - 8 {Induction of liver metastases in the rat . An experimental model for research on magnetic resonance}; Pavone P et al.; The authors report their experience in the implantation of hepatic metastases in rat, for research in magnetic resonance (MR) imaging . Tumor cells were directly injected with a fine needle into an hepatic lobe, after enzymatic disaggregation of the cell suspension . Cryopreservation of the cell line is possible after the above-mentioned preparation . Tumor implants were observed in all the 20 animals studied, with size varying from 0.5 to 2.7 cm, according to the time elapsed between inoculation and sacrifice of the rat . On MR imaging the tumors presented the same signal intensity as the corresponding human pathology, on both T1- and T2-weighted sequences . The animal model can be used for the evaluation of the efficacy of MR imaging of the liver, and mainly for the assessment of new organo-specific contrast agents. Magn Reson Imaging, 1989 Jan-Feb, 7(1), 1 - 8 Hepatic metastases: rat models for imaging research; Chen MC et al.; Improved rat liver tumor models with solitary or multiple metastatic tumors were developed for radiological imaging research . Unlike previous studies which employed trocar inoculation of tumor fragments, an enzymatically disaggregated cell suspension of mammary cancer was injected by fine needle either directly into the liver to produce solitary cancer nodules, or indirectly via the spleen or mesenteric vein to produce multiple liver metastases . Tumor size was proportional to the time elapsed after implantation . The operative mortality of direct liver, splenic parenchymal, and mesenteric inoculations were 8%, 4%, and 27%, respectively . MR tissue characteristics, image contrast, and pharmaceutical enhancement of these tumors closely resembles human hepatic metastases . The availability of reproducible, inexpensive animal models of metastatic cancer allows efficient evaluation of new liver imaging techniques. J Orthop Res, 1989, 7(1), 22 - 7 The effects of demineralized bone matrix and direct current on an "in vivo" culture of bone marrow cells; Friedenberg ZB et al.; Bone marrow cells (BMCs) from rabbit femora and tibiae were grown in diffusion chambers implanted in rabbit muscle . At 42 days 80% of the BMC chambers exhibited cartilage formation within them . Demineralized bone matrix added to the marrow cell suspension in the chamber accelerated the appearance and increased the number of chambers with cartilage . Mineralization of the cartilage also occurred earlier in the chambers with bone matrix . In a second experiment, a 5-microA direct current cathode in the bone marrow chamber increased the number of chambers containing cartilage from 50 to 80% at day 25 . Mineralization also occurred earlier in the chambers with direct current. Biomater Artif Cells Artif Organs, 1989, 17(3), 245 - 62 Dynamic evaluation of clotting phenomena in vitro and perfluorochemical oxygen transport across a membrane-bound thrombus model; Nguyen PD et al.; Citrated platelet-rich plasma was used to occlude 3-microns and 10-microns poresize Nuclepore membranes after recalcification as a thrombus model . Morphologic studies, using both light microscopy and scanning electron microscopy, indicated that over 90 percent of the number of pores available for filtration in hydrophilic and hydrophobic membranes were occluded either partially or completely . Results of transient and steady state pressure drop measurements supported the morphologic studies . It was found that the percentage of oxygen transported across the occluded membranes was greater for filtration of red blood cell suspensions diluted with a perfluorochemical emulsion than that of those diluted with Ringers . The findings in this study suggested that perfluorochemical emulsions might transport oxygen across a thrombus to maintain tissue viability during acute ischemic events. Acta Med Hung, 1989, 46(2-3), 207 - 11 Altered filtrability of white blood cells after myocardial infarction; Bogar L et al.; Abnormal white blood cell rheological behaviour has been implicated as a cause of blood flow disturbances under conditions of ischaemia and reduced perfusion pressure . Accordingly, we have tested the mechanical properties of white cells following myocardial infarction by measuring the rate at which suspension of these cells cause plugging of Nuclepore filters . The number of clogging particles in a standard white cell suspension increased by the third day after infarction but subsequently decreased to the control levels . Since white cells can cause blockage of narrow blood vessels, it is assumed that such changes in cellular properties may influence the eventual extent of infarction. Arch Dermatol Res, 1989, 281(5), 316 - 20 Induction of procoagulant activity in human epidermal cells; Schone A et al.; We have studied the induction of procoagulant activity (PCA) by lipopolysaccharide (LPS) in cultured human epidermal cells . Single cell suspensions of epidermal cells were prepared from surgical specimens and stimulated for 24 h with LPS (100 micrograms/ml) . PCA was determined by one-stage clotting assay . Stimulation of the epidermal cells with LPS resulted in a significant reduction of the clotting time (approx . 30%) as compared with the nonstimulated controls . Further analysis of the induced PCA showed that it did not require factors of the intrinsic pathway of the clotting cascade (factors XI and XII) . Similarly, PCA was not affected by factor IX-deficient plasma but required factors II, VII, and X for its full expression . PCA was inactivated by treatment with phospholipase C but not by heating to 56 degrees C . These data indicate that the epidermal cell PCA resembles tissue factor-like activity, activating the extrinsic clotting pathway . Elimination of Langerhans' cells from the epidermal cell suspension by antibody and complement-mediated lysis did not result in a reduction of PCA in the remaining epidermal cells, indicating that keratinocytes were most likely the producer cells . Induction of PCA on the cell membrane surface of epidermal cells may be an early event resulting in the initiation of a local inflammatory reaction. Leuk Res, 1989, 13(9), 825 - 31 Studies on the suppression of HL-60 cell growth in vitro by low molecular weight suppressor of human fetal liver origin; Wu CT et al.; In human fetal liver there are at least two kinds of cell growth suppressor, arginase and a low molecular weight suppressor, both are cytotoxic towards HL-60 cells under the condition of in vitro culture, and mainly present in the supernatant of fetal liver cell suspension . As compared with arginase, the low molecular weight suppressor shows a preferential suppression on HL-60 cell growth rather than that of granuloid-macrophage progenitors of normal human bone marrow. Leuk Res, 1989, 13(9), 799 - 809 Cytofluorometric analysis of thymic interdigitating cells from C57BL/6 mice prior and after leukemogenic X-irradiation; Sprecher E et al.; The thymus is populated by various Ia+ cell populations, including epithelial cells, macrophages and dendritic cells . Thymic cell suspensions were stained with an anti-Ia antibody and shown by cytofluorometry to contain a small number of strongly Ia+ cells characterized by a large diameter . The cell population was separated with the aid of the fluorescence-activated cell sorter (FACS) and characterized . They were shown to express high levels of membranal Ia antigens; they demonstrated ATPase activity and displayed the ultrastructural features characteristic of the previously described thymic interdigitating cells . C57BL/6 mice were submitted to various regimens of X-irradiation . Whereas exposure to a single dose of X-irradiation was followed by an increase in the percentage of strongly Ia+ cells, exposure to a leukemogenic regimen of fractionated X-irradiation led to a decrease in the percentage and absolute numbers of these cells in the thymus . Of the C57BL/6 mice that were irradiated with fractionated X-irradiation, 77% developed leukemia . Intravenous injection of syngeneic bone marrow one day following the last irradiation or protection of the femur during irradiation prevented both the appearance of leukemia and the disappearance of interdigitating cells . Therefore an inverse correlation between the presence of thymic dendritic cells and the incidence of leukemia in C57BL/6 mice could be demonstrated . These findings are discussed in relation to the putative role of dendritic cells in the thymus. Exp Brain Res, 1989, 76(3), 639 - 45 Developmental expression of polypeptide PEP-19 in cerebellar cell suspensions transplanted into the cerebellum of pcd mutant mice; Chang AC et al.; Cerebellar cell suspensions were prepared from normal mouse embryos and implanted into the cerebellum of Purkinje cell degeneration (pcd) mutant mice, which are characterized by a virtually complete degeneration of Purkinje cells between postnatal day (P) 17 and P45 . The expression of immunoreactivity for PEP-19, a developmentally-regulated brain-specific polypeptide, was analyzed in normal mouse cerebellum, as well as in pcd mutants with or without grafts . In the normal cerebellum, PEP-19 immunoreactivity was present in Purkinje cells . In unoperated mutants, 45 days of age or older, Purkinje cells were absent . In grafted pcd mice, numerous PEP-19 immunoreactive, neuroblast-like cells were seen in the graft at 5 days after transplantation . By 9 days, large PEP-19 immunoreactive neurons were found in the host molecular layer; by 17 days after transplantation, such neurons displayed an extensive dendritic tree and resembled differentiated Purkinje cells . The vast majority of PEP-19 immunoreactive cells was located in the molecular layer of the host at 9 days after transplantation and beyond; nonetheless, the same cells extended axonal processes toward the graft, indicating an affinity for co-grafted (possibly deep nuclei) neurons . These results point to the ability of donor Purkinje cells for survival, migration into the host brain and morphological and chemical differentiation following transplantation to the degenerated cerebellar cortex of the recipient mutants. Allerg Immunol (Leipz), 1989, 35(2), 123 - 32 Development of specific human mab's by a small scale electrofusion technique: the influence of some physical and chemical factors on hybridoma yield of human peripheral blood lymphocytes XCB-F7 fusions; Glaser RW et al.; A fusion chamber and an appropriate procedure are described which allow to fuse a sample of 15 to 25 microliters of cell suspension every two minutes . The cells can be observed throughout the process . They are not exposed to mechanical stress after the fusion pulse . Electrofusion between the heteromyeloma line CB-F7 and human mononuclear cells from peripheral blood of immunized donors is shown to provide stable hybridomas producing IgG against tetanustoxin . Pronase treatment, calmodulin, PEG, lanthanum and a number of variations in the fusion conditions were investigated as to whether they influence physical fusion of the cells, hybridoma yield, and immunoglobulin production. Ultrasound Med Biol, 1989, 15(5), 451 - 60 Histopathology of shock wave treated tumor cell suspensions and multicell tumor spheroids; Brauner T et al.; L1210 mouse leukemia cell suspensions exposed to 500 shock waves (SW) in an experimental lithotripter (XL1, Dornier) revealed severe cellular damage . Apart from cell fragments and cellular debris, cells exhibited alterations of shape, vacuolization of the cytoplasm, perinuclear cisternae, swelling of mitochondria or rupture of the mitochondrial fine structure, and permeabilization of the cell membrane . Treatment of multicell tumor spheroids of both HeLa