Biol Reprod, 1983 Mar, 28(2), 350 - 62 Prostaglandin release by zygotes and endometria of pregnant rabbits; Harper MJ et al.; When 4-day rabbit zygotes were incubated for 1 h at 37 degrees C in vitro, very little prostaglandin (PG) was released into the medium, and the concentration of PGs in the zygotes after incubation was also low . The release of prostaglandin E (PGE) and prostaglandin F (PGF) into the medium, and their concentration in the zygotes after incubation, increased sharply on Days 6 and 7 of pregnancy, reaching, by Day 7, values close to 200 ng of each PG released in 1 h per mg of protein . By contrast, endometrial samples on Days 4 and 5 of pregnancy released more PGF and less PGE than the zygotes of the same ages on a per mg of protein basis, and on Days 6 and 7, less of both PGs . Furthermore, endometrial concentrations of PGs after incubation, except for PGF on Day 4, were always lower than values for zygotes . Endometrial concentrations of PGs on Day 6 were lower before than after incubation . Although there was a slight upward trend in PG release by endometrial samples with increasing length of pregnancy, the changes were minimal and, in the case of PGE, none of the mean values exceeded 1 ng per mg of protein . In 7-day blastocysts, high levels of both PGF and PGE were found in the blastocoelic fluid, and these did not change during the 1-h incubation . The release of PGF and PGE during in vitro incubation of ruptured and washed Day 6 blastocysts was stimulated by arachidonic acid, and that of PGF, but not PGE, inhibited by indomethacin . The release of PGE, but not of PGF, from Day 6 blastocysts was inhibited by low temperature, and the same conditions inhibited release of both PGF and PGE from endometrial cell suspensions . It seems that both blastocysts and endometria have capability to synthesize PGs, the blastocysts being particularly active in this regard on Days 6 and 7 of pregnancy . It is hypothesized that, in vivo, Day 6 and 7 blastocysts release large quantities of PGs which trigger some of the local endometrial changes associated with pregnancy. Mutat Res, 1983 Mar, 108(1-3), 395 - 404 UV- and X-ray-sensitive double mutants of mouse L5178Y cells are synergistically more sensitive to 4-nitroquinoline-1-oxide than is either of the single mutants; Shiomi T et al.; The X-ray-sensitive mutant M10 and the UV-sensitive mutant Q31 of mouse lymphoma L5178Y cells are both sensitive to killing by 4-nitroquinoline-1-oxide (4NQO) . Since cell hybridization experiments showed that the 4NQO sensitivities in M10 and Q31 cells behaved as codominant traits (Shiomi et al., 1982c), it is not possible to determine by complementation test whether the M10 and the Q31 mutations responsible for 4NQO sensitivities are allelic . We have obviated this difficulty by selecting double mutants that are sensitive to both X-rays and UV . From X-ray-sensitive M10 cells, two UV-sensitive mutants (XU 1 and XU 2) were isolated by a cell-suspension spotting method . XU 1 and XU 2 were found to belong to the same complementation group as Q31 (group I) . Double mutants XU 1 and XU 2 were 30-37-fold more sensitive to 4NQO than parental L5178Y cells, whereas the single mutants M10 and Q31 were only 6-8-fold more sensitive to 4NQO than L5178Y cells in terms of D10 values (dose required to reduce survival to 10%) . These results show that the M10-Q31-double mutations enhance 4NQO sensitivity synergistically, indicating that the M10 and the Q31 mutations relevant to 4NQO sensitivities are non-allelic . The implications of this finding are discussed. Int J Lepr Other Mycobact Dis, 1983 Mar, 51(1), 64 - 71 Respiratory activities of in vitro grown Mycobacterium lepraemurium; Ishaque M; Mycobacterium lepraemurium was cultivated on Ogawa egg-yolk medium and its respiratory activities using several substrates were investigated . Glycerol and succinate were oxidized at a slow rate by the cell-free extracts prepared from in vitro grown Hawaiian and Keishicho strains of M . lepraemurium . None of the other intermediates of the glycolysis cycle as well as of the tricarboxylic acid cycle was oxidized by the whole cell suspensions or cell-free extracts . Likewise, many sulfur compounds such as cystine, mercaptosuccinate, monothioglycerol, thioacetate, etc., were inactive . However, sulfhydryl compounds such as L-cysteine, D-cysteine, DL-cysteine, dithioerythritol, dithiothritol, and DL-penicillamine were actively oxidized . Yeast extract was also readily oxidized by cell suspensions of in vitro grown M . lepraemurium . Tween 80 was very poorly oxidized by whole cell suspensions but the cell-free preparations catalyzed an active oxidation of Tween 80 . While bovine serum albumin was oxidized at a slow rate by cell-free extracts, egg albumin was inactive . The thiol-binding agents, p-hydroxymercuribenzoate and N-ethylmaleimide were effective inhibitors of succinate and NADH oxidation, thus indicating the involvement of sulfhydryl compounds in the metabolism of M . lepraemurium. Immunology, 1983 Mar, 48(3), 461 - 7 Large mononuclear Ia-positive veiled cells in Peyer's patches . II . Localization in rat Peyer's patches; Wilders MM et al.; Dendritic Ia-positive veiled cells were seen in frozen sections of rat Peyer's patches within the lymphoepithelium, in the reticular area just underneath and in the T-dependent interfollicular area . From immunohistochemical stainings with anti-IgA, IgE, IgG, IgM and monoclonal anti T lymphocyte sera it is concluded that these Ia-positive cells do not belong to lymphocyte series . The ultrastructure of these Ia-positive veiled cells resembled the morphology of the veiled cells found in Peyer's patch cell suspensions and in skin lymph . It is suggested that these cells form an antigen presenting cell system in mucosa-associated lymphoid tissue, similar to the antigen presenting cell system in the skin. Chem Biol Interact, 1983 Mar, 43(3), 253 - 61 Biochemical evidence for chemical and/or topographic differences in the lipoperoxidative processes induced by CCl4 and iron; Poli G et al.; Isolated rat hepatocytes, treated with CCl4 or ADP-Fe3+ complex show an enhanced lipid peroxidation and a decreased glucose 6-phosphatase activity . Lipid peroxidation is much more stimulated by ADP-Fe3+ or Fe3+ than by CCl4, when the metal and the haloalkane are used at a similar concentration . Increasing rates of lipid peroxidation in the different experimental conditions do not correlate with the degree of glucose 6-phosphatase inactivation, which is produced by CCl4 and not by a similar amount of ferric iron . In the case of iron, its intracellular concentration must be higher to give the enzyme inactivation exerted by CCl4 . Higher intracellular levels of iron are reached when the metal is added to the cell suspension together with ADP . Under these conditions there is inactivation of glucose 6-phosphatase . Possible mechanisms accounting for a different enzyme sensitivity to iron and CCl4 are discussed. Kidney Int, 1983 Mar, 23(3), 448 - 57 Characterization of inflammatory cells in autoimmune tubulointerstitial nephritis in rats; Mampaso FM et al.; Brown Norway rats immunized with bovine tubular basement membrane (TBM) antigens develop tubulointerstitial nephritis . The composition of the inflammatory cell infiltrate was characterized in kidney tissue sections and cell suspensions obtained from affected kidneys . Anti-TBM antibody deposition in the kidney began 8 days after immunization and was followed on days 8 to 10 by C3 deposits and infiltration of polymorphonuclear leukocytes (PMN) . After day 13, the infiltrate became almost exclusively mononuclear in character . On day 13, the inflammatory mononuclear cells recovered by Ficoll-Hypaque centrifugation contained 10% Ig+ cells (B cells), 60% W3/25+ cells (T helper cells), 9% OX8+ cells (T suppressor cells), 9% esterase+ cells (monocytes/macrophages), 4% renal cells, and 8% other unidentified cells . Monocytes/macrophages were prominent only at the latest stages of the disease . The ratio of W3/25+ to OX8+ cells was higher in the kidney than in the spleen or peripheral blood . The sequential accumulation of T cells and then monocytes/macrophages after an initial antibody, complement, and PMN lesion suggests a role for the T cells (selective prevalence of the helper T cell population over that of suppressor T cells) both as inflammatory cells and in progression and regulation of the subsequent stages of injury. Immunology, 1983 Mar, 48(3), 439 - 52 Mast cell differentiation depends on T cells and granule synthesis on fibroblasts; Davidson S et al.; Mast cell differentiation was generated in the following three experimental situations: (i) infection of mice with Schistosoma Mansoni or with Nippostrongylus brasiliensis and growth of the lymph node cells in the presence of the corresponding helminth antigen; (ii) immunization with horse serum and growth of blood and lymph node cells in the presence of the horse serum; (iii) exposure of T-cell-depleted suspensions of lymph node cells from unimmunized mice to T-cell factor (TCF) released into medium of the young cultures of (i) and (ii) . This differentiation was also obtained when lymph node cells from athymic nude mice were exposed to TCF . The cell suspensions were plated on X-irradiated fibroblast monolayers prepared from embryonic mouse skin . Screening of the suspensions before plating on the fibroblasts in culture revealed no young forms of mast cells, and none were present in culture of nude mice lymph node cells maintained without TCF . Primordial appearance of metachromatic granules generally in the golgi zone was first seen in many 'large lymphoid cells' as early as 18 hr after plating . This was followed by increase in the cytoplasm volume, increase in granule number and mitosis, ending at 10-18 days with homogeneous populations of mature mast cells . When the mesenteric lymph node cells from mice infected with the helminths were grown in the absence of fibroblasts but in the presence of the antigen, homogeneous populations of cells with extended cytoplasm, filled with unstained vacuoles developed during days 7-13 . These cells did not contain histamine (or at most 0.2 microgram per 10(6) vacuolated cells) . When these cells were plated on fibroblast monolayers clear granule formation in all the vacuoles was seen 2 days later . It increased progressively in size and staining intensity, until the vacuoles transformed into typical mast cell granules . By the fourth day the vacuolated cells attained the typical mast cell morphology and the histamine content greatly increased (from 0.12 microgram per 10(6) vacuolated cells to 3.02 micrograms per 10(6) mast cells) . These mast cells were readily degranulated by monoclonal anti-DNP-BSA IgE, and the antigen, releasing 90% of the histamine . The study shows that mucosal mast cells formation from 'large lymphoid-like' cells present in the blood and in the lymph, is stimulated by TCF . The condensation of the metachromatic material and histamine synthesis depends on other cells, presumably fibroblasts which comprise the principal cell in the embryonic skin monolayers . The mechanism of the fibroblast influence is not yet known. Exp Hematol, 1983 Mar, 11(3), 243 - 8 Hemopoietic stromal precursors in long-term culture of bone marrow: II . Significance of initial packing for creating a hemopoietic microenvironment and maintaining stromal precursors in the culture; Chertkov JL et al.; Conversion of bone marrow cells to a single cell suspension prevents them from creating a hemopoiesis maintaining adherent cell layer (ACL) in culture . The ACL of such cultures is devoid of hemopoietic stromal precursors capable of transferring the hemopoietic microenvironment on implantation under the renal capsule of syngeneic mice . The regeneration of ACL after injury is possible in 1-wk-old, but not older, Dexter-type bone marrow cultures . The results prove the significance of the initial packing of the bone marrow cells in the differentiation of the hemopoietic stromal precursors . These data contradict previous reports which concluded that the structural orderliness of stromal tissue need not be preserved for the hemopoietic microenvironment to be transferred. J Immunol Methods, 1983 Feb 25, 57(1-3), 301 - 9 A solid-phase immunoenzymatic technique for the enumeration of specific antibody-secreting cells; Sedgwick JD et al.; A sensitive immunoassay is described for the detection of idiotype- and isotype-specific antibody-secreting cells (ASC), based upon the well established principles of ELISA . Single cell suspensions containing ASC are incubated on solid phase to which specific antigen has been chemically conjugated . Antibody attaches to the latter within the immediate microenvironment of the ASC, producing localized zones of bound antibody which are subsequently developed as visual 'spots' in the ELISA . This assay system has sensitivity and specificity at least equivalent to haemolytic plaque assays. Biochem J, 1983 Feb 15, 210(2), 509 - 15 Induction by growth factors of polysaccharide synthases in bean cell suspension cultures; Bolwell GP et al.; Suspension cells of bean subcultured into medium that maintains the culture and stimulates cell division but not differentiation brings about an increase in arabinan synthase activity . Subculture into a medium that induces both cell division and xylogenesis brings about in addition an increase in xylan synthase . Both synthases are membrane-bound and are concerned with the formation of neutral pectin or hemicellulose of the cell wall respectively . During the rising phase of the induction of these activities in the appropriate culture medium, the increases in activities were inhibited by either actinomycin D (an inhibitor of transcription) or D-2-(4-methyl-2,6-dinitroanilino)-N-methylpropionamide (an inhibitor of translation) . Thus the control for the induction of the enzyme activities involves transcription and possibly translation . Subculture of the cells brought about an increase, probably non-specific, in total membrane-bound translation, as indicated by increased amounts of bound polysomes and incorporation of {35S}methionine into membrane proteins . If the control of the appearance of specific mRNA molecules is partially effected by growth factors then these are probably operative during the period of the cell cycle that is stimulated by subculture and it is probably at this time that the growth factors act to bring about the changes necessary for differentiation. Experientia, 1983 Feb 15, 39(2), 210 - 2 Pancreatic islet cell suspensions from newborn rats; different preparation procedures, viability and (pro)insulin biosynthesis; Schroder D et al.; Islet cell suspensions were prepared from neonatal rat pancreatic islets . While mechanical disintegration results in a higher yield, cells prepared by trypsin treatment appear to better preserved . Trypsin treatment of pancreatic islets during the cell preparation procedure does not influence the stimulation by glucose of (pro)insulin biosynthesis in freshly isolated cells. Eur J Biochem, 1983 Feb 15, 130(3), 575 - 80 The influence of the ionic conductance on the relation between electron transport and proton-motive force in intact cells of Rhodopseudomonas capsulata; Clark AJ et al.; 1 . The dependence of membrane potential (delta psi) on the rate of respiration in darkened intact cell suspensions of Rhodopseudomonas capsulata was distinctly non-linear: severe inhibition of respiration with either rotenone or KCN led to only a small drop in delta psi . 2 . In the presence of 0.3 microMs carbonylcyanide p-trifluoromethoxyphenylhydrazone {CF3OPhzC(CN)2} the dependence of delta psi on respiratory rate became linear . Consequently, and particularly at lower concentrations of CF3OPhzC(CN)2, there was a pronounced, synergistic depression of the respiratory delta psi with CF3OPhzC(CN)2 and either rotenone or KCN . 3 . Antimycin A, at a concentration which strongly inhibited the photosynthetic electron transport chain, only slightly lowered the light-induced delta psi in anaerobic cell suspensions . Antimycin and CF3OPhzC(CN)2 synergistically lowered delta psi generated by illumination . 4 . The light-induced delta psi in anaerobic cells was only about 1.5-times larger than the respiratory-induced delta psi in darkened cells . Nevertheless it required approximately 16-times more CF3OPhzC(CN)2 to collapse the photosynthetic delta psi than the respiratory delta psi . 5 . These results are discussed with reference to the ionic current/delta psi relation described in {J.B . Jackson (1982) FEBS Lett . 139, 139-143} . The unifying feature is that the intrinsic conductance of the cell membrane is strongly dependent on delta psi but the conductance due to CF3OPhzC(CN)2 is independent of delta psi. Biosci Rep, 1983 Feb, 3(2), 141 - 51 13C nuclear magnetic resonance studies of anaerobic glycolysis in Trypanosoma brucei spp; Mackenzie NE et al.; Anaerobic glycolysis in Trypanosoma brucei spp . has been studied by 13C NMR at 50 and 75.5 MHz . The uptake of {U-13C}glucose by cell suspensions of T . b . brucei was monitored by time-course spectroscopy, and while no anomeric specificity was found, the end-products of glycolysis were confirmed as glycerol and pyruvate together with alanine and dihydroxypropionate . The intermediacy of L-glycerol-3-phosphate was also ascertained . The incorporation of C-1 of {1-13C}glucose and of C-6 of {6-13C}glucose into glycerol and pyruvate in T . b . gambiense was quantified by measurement of the longitudinal relaxation times of the species involved . An incorporation to the extent of 66% of each substrate into equimolar amounts of glycerol and pyruvate indicate that Keq for the triosephosphate-isomerase-mediated reaction approaches unity. Cancer Res, 1983 Feb, 43(2), 617 - 22 Orthotopic implantation of primary N-{4-(5-Nitro-2-furyl)-2-thiazolyl}formamide-induced bladder cancer in bladder submucosa: an animal model for bladder cancer study; Ibrahiem EH et al.; Primary bladder tumors induced in Fischer 344 inbred rats by N-{4-(5-nitro-2-furyl)-2-thiazolyl}formamide were transplanted in syngeneic rats by the intravesical, s.c., i.v., and orthotopic routes . Attempts were made to establish bladder cancer cell lines in vitro . No success was achieved in transplantation by either the s.c., i.v., or intravesical routes when primary tumor cells were transplanted as cell suspensions . Cell suspensions of primary tumors also failed to grow in culture . However, orthotopic implantation into the bladder submucosa gave 45% success . Tumor fragments obtained from either the primary tumor or its lung metastases resulted in 10.6 and 36% tumor takes, respectively, when implanted s.c . However, after one orthotopic passage in the bladder submucosa, the tumor cells injected as cell suspension grew s.c . in 14% and orthotopically in 79% of the animals . Tumor fragments obtained from orthotopic tumors and implanted s.c . resulted in 15% tumor takes . After the second orthotopic passage, tumor cells could be grown in cultures and orthotopically in 100% of animals . The technique of orthotopic implantation as well as the usefulness of this tumor model for bladder cancer studies are described. Cancer Res, 1983 Feb, 43(2), 536 - 40 Relationship between cellular procoagulant activity and metastatic capacity of B16 mouse melanoma variants; Gilbert LC et al.; The metastatic process is a complex sequence of steps that may involve coagulation and the presence of fibrin . F1 (low incidence of lung colonization) and F10 (high incidence of lung colonization) variants of the B16 mouse melanoma were used to examine the relationship between the level of cellular procoagulant activity and their metastatic potential . Cell suspensions were prepared from cultures of B16-F1 and B16-F10 cell lines . Aliquots (0.2 ml) containing 50,000 cells were assayed for procoagulant activity in recalcified citrated rat plasma and for metastatic capacity by tail vein injection followed by counting of melanotic lung tumor colonies 17 days later . In one series of experiments, procoagulant activity and metastatic capacity were determined at 1, 2, 3, and 4 days after plating . The data showed an almost parallel decrease in both characteristics as the culture density increased . To examine the correlation between cellular procoagulant activity and the metastatic capacity of the B16 variants in two different series of experiments, regression analysis of the level of procoagulant activity and the number of lung tumor colonies gave correlation coefficients of 0.9 (n = 15) and 0.79 (n = 8) . These results suggest that fibrin formation resulting from cellular procoagulant activity may play a role in the metastatic process. J Gen Physiol, 1983 Feb, 81(2), 283 - 304 Permeability of human red cells to a homologous series of aliphatic alcohols . Limitations of the continuous flow-tube method; Brahm J; Human red cell permeability to the homologous series of methanol, ethanol, n-propanol, n-butanol, and n-hexanol was determined in tracer efflux experiments by the continuous flow tube method, whose time resolution is 2-3 ms . Control experiments showed that unstirred layers in the cell suspension were less than 2 X 10(-4) cm, and that permeabilities less than or equal to 10(-2) cm s-1 can be determined with the method . Alcohol permeability varied with the chain length (25 degrees C): Pmeth 3.7 X 10(-3) cm s-1, Peth 2.1 X 10(-3) cm s-1, Pprop 6.5 X 10(-3) cm s-1, Pbut less than or equal to 61 X 10(-3) cm s-1, Phex 8.7 X 10(-3) cm s-1 . The permeability for methanol, ethanol, and n-propanol was concentration independent (1-500 mM) . The permeability to n-butanol and n-hexanol, however, increased above the upper limit of determination at alcohol concentrations of 100 and 25 mM, respectively . The activation energies for the permeability to methanol, n-propanol, and n-hexanol were similar, 50-63 kJ mol-1 . Methanol permeability was not reduced by p-chloromercuribenzene sulfonate (PCMBS), thiourea, or phloretin, which inhibit transport of water or hydrophilic nonelectrolytes . It is concluded (a) that all the alcohols predominantly permeate the membrane lipid bilayer structure; (b) that both the distribution coefficient and the diffusion coefficient of the alcohols within the membrane determine the permeability, and (c) that the relative importance of the two factors varies with changes in the chain length. J Gen Physiol, 1983 Feb, 81(2), 239 - 53 Reflection coefficient and permeability of urea and ethylene glycol in the human red cell membrane; Levitt DG et al.; The reflection coefficient (sigma) and permeability (P) of urea and ethylene glycol were determined by fitting the equations of Kedem and Katchalsky (1958) to the change in light scattering produced by adding a permeable solute to a red cell suspension . The measurements incorporated three important modifications: (a) the injection artifact was eliminated by using echinocyte cells; (b) the use of an additional adjustable parameter (Km), the effective dissociation constant at the inner side of the membrane; (c) the light scattering is not directly proportional to cell volume (as is usually assumed) because refractive index and scattering properties of the cell depend on the intracellular permeable solute concentration . This necessitates calibrating for known changes in refractive index (by the addition of dextran) and cell volume (by varying the NaCl concentration) . The best fit was for sigma = 0.95, Po = 8.3 X 10(-4) cm/s, and Km = 100 mM for urea and sigma = 1.0, Po = 3.9 X 10(-4) cm/s, and Km = 30 mM for ethylene glycol . The effects of the inhibitors copper, phloretin, p-chloromercuriphenylsulfonate, and 5,5'-dithiobis (2-nitro) benzoic acid on the urea, ethylene glycol, and water permeability were determined . The results suggest that there are three separate, independent transport systems: one for water, one for urea and related compounds, and one for ethylene glycol and glycerol. Am J Hematol, 1983 Feb, 14(1), 27 - 36 Mechanism of canine cyclic hematopoiesis: the role of prostaglandin E in feedback regulation; Hammond WP et al.; Prostaglandin E inhibits granulocyte-macrophage colony formation in vitro in man and mouse, suggesting that it plays a role in feedback regulation of granulocyte production in vivo . Therefore, we examined the role of PGE in normal canine hematopoiesis and its potential role in the pathogenesis of cyclic hematopoiesis in grey collie dogs . The prostaglandin synthesis inhibitors indomethacin and ibuprofen (10(-5) M) increased CFU-C growth to 194 and 160% of control, respectively, while PGE2 addition caused a dose-dependent inhibition of bone marrow CFU-C growth in both normal and grey collie dogs . These concentrations of indomethacin and ibuprofen decreased bone marrow cell elaboration of PGE measured by radioimmunoassay to less than 5% of control values . The levels of PGE in leukocyte conditioned medium prepared from grey collies correlated with the number of monocytes in the conditioning cell suspension (r = 0.78, n = 10, p less than 0.05) so that PGE production per monocyte was no different in normal and grey collie dogs . The effect of PGE2 upon CFU-C was to inhibit formation of macrophage, but not neutrophil colony subtypes . These findings make aberrant PGE-mediated inhibition of precursor cells an unlikely mechanism to cause cyclic hematopoiesis, and show that PGE produced by monocytes acts as a feedback inhibitor for precursor cells destined to produce monocytes but not for those destined to form neutrophils. Scand J Immunol, 1983 Feb, 17(2), 123 - 8 Quantitation and estimation of cooperation between target-binding sites in natural and antibody-dependent cell-mediated cytotoxicity by use of a mathematical transformation . Influence of interferon; Krebs HJ et al.; We have studied the use of a mathematical transformation, the Hill transformation, in natural and antibody-dependent cell-mediated cytotoxicity as a function of effector cell concentration . It can be concluded that when adherent cells are removed from the effector cell suspension, cooperation between binding sites for effector cells on the target cell changes from negative to zero . After stimulation of nonadherent cells with alpha-interferon, the binding sites still remain noninteracting . This is the case both in natural and in antibody-dependent cell-mediated cytotoxicity experiments . The Hill transformation seems to be an easy and easily reproducible way of quantitating cytotoxicity. Int J Radiat Oncol Biol Phys, 1983 Feb, 9(2), 217 - 20 Response of fibrosarcoma cell subpopulations to small doses of radiation delivered in situ; Thames HD Jr et al.; The survival of cells from 2 tumor subpopulations after gamma-ray doses ranging from 1 to 19 Gy was determined using a lung colony assay . Methylcholanthrene-induced fibrosarcomas grown in the hind legs of C3H/Kam pathogen-free mice were irradiated in situ when the tumors were 8-10 mm in diameter . Single cell suspensions prepared from excised tumors were separated on a linear density gradient, and the clonogenicity of predominantly oxic Band 2 (density 1.08 g/cm3) and predominantly hypoxic Band 4 (density 1.14 gm/cm3) cells was measured . The surviving fraction of cells after doses of 1, 2, and 3 Gy was estimated from that measured after total doses of 5 Gy = 5 X 1 Gy, 10 Gy = 5 X 2 Gy, and 15 Gy = 5 X 3 Gy, under the assumption of equal effect per fraction (checked by estimating survival at 3 Gy after different numbers of fractions) . Very little curvature was evident in the survival curves of Band 2 and Band 4 cells (beta/alpha = .013-.034 Gy-1) . The initial segment of the survival curve of the predominantly oxic Band 2 cells was steeper (1Do = 3.6 Gy) than that of the predominantly hypoxic Band 4 cells (1Do = 5.2 Gy); both remained linear over a large range, to doses in excess of 3 Gy . These results imply that these tumor subpopulations will be insensitive, in their response to multifractionated regimens, to changes in size of dose per fraction in the range 0 to 3 Gy, a trait shared by two acutely responding normal tissues (murine testis and jejunum). J Bacteriol, 1983 Feb, 153(2), 916 - 20 A voltage clamp inhibits chemotaxis of Spirochaeta aurantia; Goulbourne EA Jr et al.; Anaerobic conditions were employed to study the relationship between membrane potential and chemotaxis in Spirochaeta aurantia . When cells were grown anaerobically and suspended in anaerobic potassium phosphate buffer (pH 5.5), membranes did not appear to be polarized . Nevertheless, motility was supported by a transmembrane pH gradient, and the anaerobic cells exhibited D-xylose taxis . Introduction of trace amounts of air into anaerobic cell suspensions resulted in a transient membrane polarization . The addition of valinomycin to cells suspended under anaerobic conditions did not alter the steady-state value of membrane potential appreciably but served to clamp membrane potential at the preset level . Although there was no detectable effect of valinomycin on the motility of anaerobic cells in potassium phosphate buffer, D-xylose taxis was completely inhibited by this treatment . These data indicate the the action of valinomycin as a voltage clamp serves to inhibit the chemotaxis of S . aurantia and provide evidence to support the suggestion that the mechanism of chemotaxis in this organism involves the transduction of sensory signals in the form of membrane potential fluctuations. Vet Med (Praha), 1983 Feb, 28(2), 119 - 25 {The effect of different cell concentrations and incubation time of testicular tissue testosterone synthesis}; Mamode MI et al.; The cells of the testes of mice were enzymatically separated and the amount of Leydig cells was determined in different stages of dispersion and after washing the separated tissue . This amount ranged from 2 to 9% . The largest quantity of Leydig cells (9%) was obtained when separated tubuli were washed . The response of cell suspensions at seven concentrations stimulated by human chorion gonadotrophin (HCG) was tested . Cell suspension concentrations from 5.3 x 10(5) to 1.4 x 10(6) cells/ml were found to be satisfactory . After two to three hours of incubation, the values of testosterone could be used for the determination of the activity of gonadotropic preparations. Toxicol Appl Pharmacol, 1983 Feb, 67(2), 292 - 301 Interactions of aflatoxin B1 and blood components of various species in vitro: interconversion of aflatoxin B1 and aflatoxicol in the blood; Kumagai S et al.; The fate of aflatoxin B1 (AFB1) in the blood of various species of animals was studied in vitro . Examination of the distribution of radioactivity in blood incubated with {14C}AFB1 at 37 degrees C showed that high levels of radioactivity were associated with blood cells . The radioactivity was readily removed from the blood cells by washing with fresh plasma, indicating loose binding of AFB1 to blood cells . Most of the radioactivity in plasma was bound to protein . These results suggest that a large part of the AFB1 in blood in vivo may be carried not only by the plasma proteins but also by the blood cells . When chloroform extracts of plasma of {14C}AFB1-treated mouse, rat, duckling, and hamster blood were developed by thin-layer chromatography, high levels of radioactivity were found in both the AFB1 region and the aflatoxicol (AFL) region . Incubation of blood with nonradioactive AFB1 and AFL showed marked interconversion of AFB1 and AFL in the blood of rats, hamsters, mice, and Mongolian gerbils, but not in the blood of guinea pigs, rhesus monkeys, squirrel monkeys, or humans . Interconversion occurred in red blood cell suspensions but not in plasma, indicating that the red blood cells are responsible for AFB1-AFL interconversion in the blood. J Immunol, 1983 Feb, 130(2), 951 - 7 Studies of allogeneic tumor transplants: induced rejection of advanced tumors by immune alteration of recipients; Russell PS et al.; In the present experiments, a methylcholanthrene-induced sarcoma (S-702) of B10.D2 origin was found to grow rapidly in B6AF1 mice leading to the death of all recipients in 5 to 9 wk . Nevertheless, immunity to MHC antigens presented by the tumor was readily demonstrable in tumor-bearing mice by their responses to donor strain skin grafts until late in the course of tumor growth, when a nonspecific form of immune suppression developed . In addition, B6AF1 mice preimmunized by exposure to B10.D2 donor strain antigens did not permit tumor growth . Treatment of tumor-bearing B6AF1 mice with CY at 18 days, when the tumors measured over 12-mm in diameter, followed by the i.p . injection of B10.D2 lymphoid cells (at a dosage of from 1.2 to 2.5 X 10(8) cells) resulted in the complete regression of 100% of these large tumors . CY treatment combined with localized immune stimuli in the form of donor strain skin grafts or secondary tumor implants was incapable of producing a sufficiently heightened immune response to cause tumor rejection . A dose of CY temporarily retarded tumor growth in most mice, and in a minority of animals so treated (less than 25%) tumors regressed completely . In syngeneic (B10.D2) animals, CY also temporarily slowed tumor growth, but total regression was never observed . An effective B10.D2 cell inoculum could consist not only of living lymphoid cells but of irradiated (1000 rad) cells as well . Tumor cell suspensions (after irradiation, 10,000 rad) were also effective . These observations suggest local immune factors at the host-tumor interface may have been of importance in the survival of these allogeneic tumor transplants and that CY influenced this state, perhaps through an influence on suppressor cells, allowing subsequent administration of donor strain cellular antigens to induce an effective tumor rejection response. J Steroid Biochem, 1983 Feb, 18(2), 205 - 8 Angiotensin II potentiates ACTH-stimulated adrenal androgen secretion; Parker LN et al.; Several lines of evidence in animal and human studies, including measurements of elevated adrenal androgens in salt wasting syndromes suggest that adrenal androgen levels may in part be regulated by angiotensin II . This possibility was tested directly by measurement of cortisol and dehydroepiandrosterone (DHA) in canine adrenal cell suspensions after addition of angiotensin II and ACTH, separately and together . Minimal cortisol and no DHA stimulation was obtained using 4 x 10(-10) to 4 x 10(-5) M concentrations of angiotensin II alone . However, increased cortisol and DHA secretion were observed beginning at 4 x 10(-10) M concentrations of angiotensin II when it was combined with 10(-13) MACTH . These are physiological concentrations of both stimuli and may explain the increased adrenal androgens seen in some pathological situations characterized by elevated PRA. Cell Immunol, 1983 Feb 1, 75(2), 348 - 55 Membrane phenotype of murine effector and suppressor T cells involved in delayed hypersensitivity and protective immunity to herpes simplex virus; Nash AA et al.; The membrane phenotype of T cells involved in delayed hypersensitivity (DH), protective immunity, and suppression of delayed hypersensitivity to herpes simplex virus (HSV) has been determined . T cells from immune lymph nodes transferring DH and antiviral immunity to normal recipients were characterized as Lyt 1+2- . There appeared to be no detectable antiviral role for Lyt 1-2+ cells in the transferred cell suspension . Splenic T cells suppressing the induction of DH to HSV were characterized as being both Lyt 1+2- and Lyt 1-2+ 4 weeks after their induction . At earlier times, i.e., after 7 days, the suppression was mediated solely by the Lyt 1+2- population . Thereafter, a progressive increase in the contribution of the Lyt 1-2+ suppressor was observed . Both the early and later phases of suppression were due to I-J positive cells . The nature of the two suppressor cell types is discussed in relation to suppressor cell "cascades" and to the pathogenesis of herpes simplex virus infection. J Cutan Pathol, 1983 Feb, 10(1), 33 - 51 Flow cytometry of keratinocytes; Clausen OP; A prerequisite for using flow cytometry (FCM) is the availability of isolated single cells . Procedures for separation and isolation of keratinocytes from animals and man are available, and the resulting single cell suspensions have been subjected to FCM measurements . The major advantage of the method is the accuracy and speed with which a variety of cellular constituents can be quantified . FCM of keratinocytes has, hitherto, been mainly confined to measurements of nuclear DNA for estimation of cell-cycle distributions and for ploidy studies . In mouse epidermis, cell-cycle distributions were estimated from sequentially obtained DNA histograms and evaluated with other cell kinetic measurements, resulting in new information about epidermal cell-cycle progression, not achievable by any of the methods alone . The best way, therefore, to increase our knowledge of keratinocyte proliferation, is the combined use of DNA FCM and other cell kinetic methods . DNA FCM has also been applied to healthy and diseased human epidermis, and may add valuable information to the classification of skin disease in selected cases . It is believed that further progress in the characterization of keratinocyte growth and development will depend on parameters other than DNA alone. J Biol Chem, 1983 Jan 10, 258(1), 636 - 42 Tissue distribution, structural characterization, and biosynthesis of Mac-3, a macrophage surface glycoprotein exhibiting molecular weight heterogeneity; Ho MK et al.; Mac-3 is a mouse macrophage differentiation antigen defined by a rat anti-mouse monoclonal antibody (MAb),M3/84 . The structure, biosynthesis, quantitative surface expression, and distribution of Mac-3 have been studied by radiolabeling and isolation with MAb-Sepharose, saturation binding, absorption, and immunofluorescence flow cytometry . In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Mac-3 migrates as a diffuse band with average Mr = 110,000 . Labeling of intact cells with 125I and accessibility to MAb show it is present at least in part on the cell surface . Saturation labeling with 125I-MAb shows 4.2 X 10(4) cell surface sites on thioglycollate medium-elicited peritoneal macrophages . {35S}Methionine and {3H}glucosamine incorporation into Mac-3 by purified macrophages show it is a glycoprotein synthesized by these cells . Absorption shows Mac-3 is strongest in macrophages, present in lower quantities in lung, liver, bone marrow, and spleen, and undetectable in thymus, lymph node, brain, and heart . Immunofluorescent flow cytometry shows surface expression on thioglycollate-elicited macrophages but not bone marrow, spleen, lymph node, or thymus cell suspensions . Similar amounts of Mac-3 are immunoprecipitated from resident macrophages or macrophages elicited by sterile inflammatory agents, intracellular parasites, or immunomodulators, but the average Mr of Mac-3 varies from 92,000 to 110,000 . Mac-3 is synthesized from precursor(s) of Mr = 74,000 and 79,000, identical in the different macrophages . Processing into the mature molecule, which migrates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a more diffuse band and varies in Mr among macrophage elicited by different agents and to a lesser degree between different preparations of the same type of macrophage, occurs in 15 to 30 min. Cell Tissue Res, 1983, 232(3), 539 - 52 Ultrastructural and functional development of macrophages in the dermal tissue of rat fetuses; Takahashi K et al.; After about 12 days of gestation, fetal macrophages begin to appear in the subepidermal mesenchyme of rat fetuses . The macrophages are ultrastructurally characterized by cytoplasmic vacuoles, abundant polyribosomes and long filopodia . Immunocytologically, they possess Fc and complement (C3) receptors on the cell surface and are capable of immune phagocytosis, Latex or carbon phagocytosis, and glass adherence . From 15 days of gestation, lysosomal granules and micropinocytic vesicles gradually develop, together with an enlargement of Golgi complexes, whereas the number of polysomes and the number and size of cytoplasmic vacuoles are gradually reduced when gestation ends . Finally, the macrophages become amoeboid . Non-specific esterase and endogenous peroxidase activities are always absent in these macrophages . In culture experiments with cell suspensions prepared from the mesenchyme, fetal macrophages show a similar maturation process . Autoradiography with 3H-thymidine demonstrates a high proliferative capacity of the macrophages, particularly during the fetal stage. Hemoglobin, 1983, 7(3), 205 - 26 Characterization and properties of Hb York (beta 146 His leads to Pro); Kosugi H et al.; A second case of Hb York (beta 146 His leads to Pro), was discovered in a patient with polycythemia . The oxygen equilibrium curves (OEC) of red cell suspensions in a buffer (pH 7.4) at 37 degrees C revealed a biphasic curve with a P50 of only 12.5 mm Hg (normal value: 26.5 +/- 1.0 mm Hg) . The purified Hb York had an extremely high affinity for oxygen with diminished cooperativity and decreased Bohr effect . The oxygen affinity was significantly reduced by inositol hexaphosphate . Molecular stability studies by mechanical shaking of various liganded forms of Hb York revealed stabilities between those of Hb A and Hb S . Isolated beta Y-subunits were more unstable than beta A-subunits at every pH examined . Hb York was 1.4 times more unstable than Hb A in 18.9% isopropanol. Biorheology, 1983, 20(1), 41 - 56 Theoretical modeling of filtration of blood cell suspensions; Skalak R et al.; A theoretical model of filtration of suspensions containing red blood cells (RBCs) and white blood cells (WBCs) has been developed . Equations are written for the pressure drop, the filtration flow and the fractions of filter pores containing RBCs (alpha) and WBCs (alpha*) . Because the relative resistances (ratios of resistance of cell to resistance of suspending fluid) of RBCs (beta) and WBCs (beta*) through the filter pore are greater than one, the transit of these cells (especially WBCs) through the filter is slower than that of suspending fluid; this leads to values of alpha and alpha* higher than those simply expected from the hematocrit and leukocrit, respectively, in the entering and exiting suspensions . In the absence of pore plugging by the cells (steady flow), the pressure drop can be computed from alpha, alpha*, beta and beta* . In order to model unsteady flow, differential equations are written to include pore plugging and the subsequent unplugging by the rising filtration pressure at a constant flow . By specifying the fractions of entering RBCs (epsilon) and WBCs (epsilon*) which would plug the pores and the rate at which the plugged pores would unplug in response to pressure rise (epsilon u), as well as the fractions of entering RBCs (epsilon p) and WBCs (epsilon p*) that would plug the pores permanently, theoretical pressure-time curves can be generated by numerical integration, and the results fit the experimental data well . From such fitting of theoretical curve to experimental data, information can be deduced for epsilon, epsilon*, epsilon u, epsilon p and epsilon* p. Biorheology, 1983, 20(1), 29 - 40 Influence of red cell concentration on filtration of blood cell suspensions; Schmalzer EA et al.; Pressure-time curves obtained by passing suspensions of blood cells in Ringer solution through a 5 microns polycarbonate filter at constant flow (1.6 ml/min) were evaluated for their ability to reflect the deformability of the erythrocytes . The initial pressure reading (Pi) obtained in a quasi-steady state during the first 1-2 sec of pumping was found to be reproducible for hematocrit values between 10 and 30 percent . This Pi value was normalized by the pressure generated by the cell-free suspending medium (PO) at the same flow rate . The ratio Pi/PO was found to be linearly proportional to hematocrit up to 30 percent but independent of leukocyte concentration up to 12,000/mm3 . Later portions of the curve did vary with leukocyte count . By using the equations developed from theoretical modeling of cells passing through a filter, the experimentally determined relation of Pi/PO to hematocrit, and the known geometry of the filter pores, we were able to calculate parameters reflecting the deformability of red cells . These include beta, the ratio of resistance in a pore containing a red cell to that in a pore containing only the suspending medium, and alpha, the proportion of pores filled by erythrocytes in transit . The application of theoretical analysis to experimental data has provided quantitative insights into the behavior of red cells during filtration tests in normal and disease states. Biorheology, 1983, 20(1), 11 - 27 Role of white blood cells in filtration of blood cell suspensions; Chien S et al.; The time-dependent filtration pressure curves of cell suspensions pumped through 5 microns polycarbonate filters at a constant flow rate were analyzed with the aid of a theoretical model developed in an accompanying paper . The cell suspensions contained mixtures of erythrocytes and leukocytes, the concentrations of which were systematically varied . The pressure-time (P-t) curves generally showed multiphasic components . Following the attainment of a quasi-steady state level, the pressure rose first rapidly and then more slowly . The rates of pressure rise in the fast and slow phases were normalized by using the steady state pressure reading (PO) obtained with Ringer solution at the same flow rate, and are designated k1 and k2, respectively . Both k1 and k2 increased with rising concentrations of leukocytes, {WBC}, or erythrocytes, {RBC} . {WBC} is 700-1000 times more effective than {RBC} in affecting k1 and k2 . k1 is related to the dynamic plugging and unplugging of filter pores, primarily by leukocytes . k2 is attributable to the "permanent" plugging of filter pores, again predominantly by leukocytes . The experimental P-t curves can be fitted with the theoretical model by using appropriate constants for leukocyte plugging . The results indicate that nearly 2/3 of the entering leukocytes cause transient plugging of pores, with an unplugging rate of 4.1 percent/sec/unit pressure rise, and that approximately 2.2 percent of the entering leukocytes are "permanently" lodged . These results underscore the important role of leukocytes in determining the later phase of the P-t curve and support the concept that leukocyte plugging may have pathophysiological significance in causing microvascular occlusion in disease states. Nauchnye Doki Vyss Shkoly Biol Nauki, 1983, (1), 85 - 8 {Effect of carbon monoxide on the growth of sulfate-reducing bacteria and their oxidation of this substrate}; Karpilova IIu et al.; The effect of carbon monoxide on the growth of six strains of sulfatee-reducing bacteria have been studied as well as the ability of bacterial suspensions and extracts to oxidize CO . It was shown that sulfate-reducing bacteria possess a comparably high resistance to carbon monoxide . There are difference in the sensitivity of certain species and strains of sulphat-reducing bacteria to the content of CO in the gas phase . The cell suspensions and extracts are capable of oxidizing 100% CO in gaseous phase . The rate of carbon monoxide oxidation by extracts is much higher than by suspensions. Invasion Metastasis, 1983, 3(4), 243 - 8 Plasminogen activators as markers of tumor colonization potential; Ng R et al.; Cell suspensions from the R 3230 AC rat mammary adenocarcinoma, when injected intravenously into F344 rats, invariably produce multiple lung foci within 10 days . We compared the colonization potential of cultures obtained from these foci and from cell populations exposed to 100 micrograms/ml medium of both concanavalin A and wheat germ agglutinin for 5 passages with the original cell line . Plasminogen activator activity (PAA) was determined in all three cell subpopulations, using S2251 (KABI) as chromogenic substrate . All cell lines retained their ability to grow after subcutaneous implant . The lectin resistant variant was found to have lost its capacity to nidate in the lung completely and also had the lowest PAA . In contrast, the cell population derived from the lung foci ranked highest in PAA. Biorheology, 1983, 20(5), 557 - 67 Shear viscoelasticity of suspensions of biological cells with fluid membrane; Takano Y et al.; In order to consider the effect of membrane fluidity upon the mechanical property of biological cell suspensions, we have calculated the complex intrinsic viscosity {eta*} = {eta'} - i{eta"} of spherical shell structures with material incompressibility in suspension as a function of the dimensionless frequency x = omega eta'a/gamma' together with the parameters of hm = eta m/eta', g = gamma/gamma', h = eta/eta', delta = d/a, where a is the radius of the cell, d is the width of the membrane, eta, eta m, and eta' are the viscosities of the medium, of the membrane and of the internal region of the cell, gamma and gamma' the surface tensions at the outer and the inner side of the membrane respectively, and omega the angular frequency . The result is simply represented by two dispersions as follows: {eta*}/{eta} = A1 + B1/(1 + i omega tau 1) + B2/(1 + i omega tau 2) . Here i is the imaginary unit, A1 = 2(1 - h)/(2 + 3h) + O(delta), B1 = 3h/(5 + 5h) + O(delta), B2 = h (19 + 16h)/{5(1 + h) (2 + 3h)} + O(delta), tau 1 = {(5/24) (1 + h) (1 + 1/g) delta-2 + O(delta-1)} a eta'/gamma', tau 2 = {(2 + 3h) (19 + 16h)/{40 (1 + h) (1 + g)} + O(delta)} a eta'/gamma', and {eta} = (5/2) {96hmg + 32g (5 + 5h - 12hm)delta + O(delta 2)}/{96hmg + 32g (5 + 2h - 12hm) delta + O(delta 2)}. Biorheology, 1983, 20(5), 471 - 83 Theory of non-Newtonian viscosity of red blood cell suspension: effect of red cell deformation; Murata T; The effects of the deformation of red blood cells on non-Newtonian viscosity of a concentrated red cell suspension are investigated theoretically . To simplify the problem an elastic spherical shell filled with an incompressible Newtonian fluid is considered as a model of a normal red cell . The equation of the surface of the shell suspended in a steady simple shear flow is calculated on the assumption that the deformation from a spherical shape is very small . The relative viscosity of a concentrated suspension of such particles is obtained based on the "free surface cell" method proposed by Happel . It is shown that the relative viscosity decreases as the shear rate increases. Biomed Biochim Acta, 1983, 42(11-12), S332 - 6 CDS-AG medium for red blood cell preservation; Strauss D; Buffy coat-free red cell concentrates (RCC) from ACD, ACD-AG, and EDTA blood were prepared at the day of collection and resuspended with about one half of the packed red cell volume of a citrate-dextrose-sucrose-adenine-guanosine solution (CDS-AG) . The posttransfusion survival of RBC in red cell suspensions (RCS) amounted to about 80% after 35 days of storage . 50 to 63% of the normal ATP level still remained . About 0.3% of red cells were hemolysed . 10% of red cells existed unchanged as discocytes, about 85% were transformed to echinocytes and 5% to spherocytes . The MCHC increased by about 25% due to a shrinkage of RBC . A much more hypertonic citrate-saline anticoagulant solution (420 mosmol/kg) increased the shrinkage, led to a higher hemolysis and lower posttransfusion survival rates. Biorheology, 1983, 20(3), 311 - 6 Indices of filterability of red blood cell suspensions; Skalak R et al.; A number of different experimental techniques have been devised in recent years to use microsieving as a test of the filterability of suspensions of red blood cells . Various indices have been proposed to express the results of these tests . In the present paper a correlation is made of the intrinsic increase in resistance at the level of a single pore in the filter to the macroscopically observed pressure and flow through the entire filter . Further it is shown how a number of different tests may be used to derive the same index . The results apply only to situations in which there is no plugging of pores. Biorheology, 1983, 20(3), 295 - 309 The bulk rheology of close-packed red blood cells in shear flow; Secomb TW et al.; A theoretical analysis is made of the dynamical behavior and bulk rheology of close-packed red blood cell suspensions subjected to simple shear flow . The model for the polyhedral cell shapes and tank-treading membrane motion developed in the companion paper (1) is used . The flow in the thin lubricating plasma layers between cells is analyzed taking into account the mechanical properties of the membrane at the corner regions of sharp membrane curvature . This leads to predictions for the apparent viscosity as a function of hematocrit and shear rate . Good agreement with experimental results is obtained at moderate and high shear rates (above 20 s-1) . At lower shear rates, a rapid rise in apparent viscosity has been found experimentally, and the mechanisms leading to this behavior are examined. Biorheology, 1983, 20(3), 283 - 94 The motion of close-packed red blood cells in shear flow; Secomb TW et al.; Experimental and theoretical results are presented concerning the motion of close-packed red blood cell suspensions subjected to steady simple shear flow . The behavior of the suspension was observed microscopically using a cone-and-plate rheoscope . At moderate and high shear rates the cells show a fairly orderly arrangement, each appearing polygonal in the field of view . An idealized theoretical model for the suspension is developed, in which each cell is a 14-sided polyhedron of varying shape, but with constant surface area and volume . Tank-treading motion of the membrane is predicted, and an approximation to the motion is calculated which is consistent with the known mechanical properties of the membrane . It is shown that considerably more energy is dissipated in the membrane than in the cytoplasm during tank-treading. Ann Rech Vet, 1983, 14(2), 163 - 8 A laboratory reference vaccine to titrate immunogenic activity of antibrucella vaccines in mice; Bosseray N et al.; The number of bacteria (CFU) in spleens of mice fifteen days after a standard intraperitoneal challenge of Brucella abortus, is dependent on vaccinal immune status of mice . From this observation, a control method of vaccinal activity was previously proposed, which classified the responses in relation to fixed reference values . A reference vaccine, a lyophilized formalin-killed bacterial cell suspension of B . melitensis strains H38 was prepared and titrated . From the dose response curve, the quantities giving reference values were calculated and expressed in a Unit system . This vaccine makes possible inter-laboratory comparisons of vaccinal activity, that can be expressed on the Units basis. Arch Immunol Ther Exp (Warsz), 1983, 31(2), 183 - 9 The use of protein beads as immunoadsorbent for the column fractionation of lymphocytes; Eckert R et al.; Beads of calf serum proteins (CSB) with antigen-antibody complexes or antigen by activation with glutaraldehyde were used as immunoadsorbents for the fractionation of mouse lymphocytes . T-lymphocytes could be separated by this method with high purity . The precursors of antibody-forming cells were completely eliminated from spleen and bone marrow cell suspensions . The unspecific binding of lymphocytes to CBS or Sepharose was similar and not selective for T or B lymphocytes. Int J Immunopharmacol, 1983, 5(4), 283 - 8 The in vitro effect of phenytoin and carbamazepine on subpopulations of human blood mononuclear cells; Gilhus NE; Mononuclear cells from peripheral blood of 10 healthy blood donors were incubated with phenytoin and carbamazepine dissolved in 1% propyleneglycol . Phenytoin 20 mg/1 significantly reduced the percentage of active E rosette-forming T-lymphocytes; to mean 17.6% compared to mean 25.9% in control incubations (P less than 0.05) . Carbamazepine 10 mg/1 reduced this percentage to 21.0% (0.05 less than P less than 0.10) . Phenytoin reduced the percentage of active T-lymphocytes in 9 of the 10 cell suspensions, while carbamazepine reduced the active T-lymphocytes in 8 of the 10 suspensions . The percentage of total E rosette-forming T-lymphocytes was similarly reduced by 20 mg/1 phenytoin and 10 mg/1 carbamazepine; from 65.3 to 59.5% and to 60.3%, respectively (P less than 0.05, 0.05 less than P less than 0.10) . The reduction of active and total T-lymphocytes was concentration-dependent for both drugs . Phenytoin and carbamazepine 5 mg/1 did not influence the percentage of T-lymphocytes . The decrease became apparent at a concentration of 10 mg/1 for both drugs, and grew steadily more marked with increasing drug concentrations up to 80 mg/1 . However, the reduction in the percentage of T-lymphocytes was more pronounced for phenytoin than for carbamazepine at all drug concentrations . The percentage of cells with Fc gamma-receptors and of those with receptors for the activated human complement component C3b, were not influenced by phenytoin and carbamazepine, nor were the cells with phagocytizing capacity and the non-phagocytizing cells with membrane-bound immunoglobulin (i.e . B-lymphocytes). Z Rechtsmed, 1983, 90(2), 127 - 36 {Enzyme activity of isolated leukocyte populations . II . Cytochemical and zymographic studies of cadaver blood}; Oehmichen M et al.; Blood was taken from the femoral vein of 17 autopsied cadavers with different diagnoses and postmortal intervals (10-120 h) . The granulocytes and lymphocytes were isolated with routine methods . The cell suspensions were subject to morphologic, enzyme-cytochemical (naphthol AS-D chloroacetate esterase) and electrophoretic (PGM1, PGM3, GOTM, PEPA, MEM, FUCA) investigations . The following results were obtained: Erythrocyte-free cell suspensions are only found during short postmortal intervals; Isolation of pure lymphocytes from cadaver blood using the described method is only possible very early in the postmortal interval (within 10 h); The isolated granulocytes contain an impressively high percentage of eosinophilic granulocytes; The percentage of naphthol AS-D-chloroacetate esterase-positive granulocytes is considerably lower in stored, conserved blood than in blood smears; Identification of the above mentioned enzymes from isolated granulocytes from all cadavers is possible by electrophoresis. Z Rechtsmed, 1983, 90(2), 115 - 25 {Enzyme activity of isolated leukocyte populations . I . Cytochemical and zymographic studies of stored blood under various storage conditions}; Kompf J et al.; Heparinized venous blood was stored under sterile conditions at different temperatures (4 C, 20 C, 37 C) for various intervals (0-7 days) . After storage the granulocytes and lymphocytes were isolated with routine methods . Naphthol AS-D-chloroacetate esterase as a granulocyte marker and acid alpha-naphthyl acetate esterase as a T-lymphocyte marker were identified on smears of the washed cell suspension . Different enzymes were identified in the cell sediment with electrophoresis . Relatively pure lymphocyte suspensions were obtained within the first 24 h . After this time, however, the percentage of these mononuclear cells declined markedly . The percentage of isolated granulocytes varied slightly; there was a marked predominance of granulocytes (more than 70%) at all intervals investigated during the isolation . Cytochemical analysis of the granulocytes and lymphocytes indicated that the decrease in the percentage of enzyme-positive cells depends in each case on the duration of the storage interval . During the first 24 h, only PGM1 and GOTM could be identified in the lymphocyte suspension with horizontal starch gel electrophoresis . The enzymes PGM1, PGM3, PGI, MDH, GOTM, 6-PGD, ADA could always be identified in the granulocyte suspension; AK, FUCA, MEM could be occasionally identified; and GPT and GLO could never be identified. Leuk Res, 1983, 7(4), 523 - 37 Non-Hodgkin's lymphoma phenotyping: problems in the use of heterologous and monoclonal antibodies; Barcos M et al.; Cell suspensions or frozen sections of lymph node biopsies from 32 patients with non-Hodgkin's lymphoma (NHL) were studied for sheep erythrocyte (E)-binding under three conditions (Estandard, EAET, Egravity), Fc and C receptors, immunoglobulin (Ig) heavy and light chain class and reactivity with heterologous antisera to T cells (T-LCL), HLA-D (Ia-like) and common acute lymphocytic leukemia (c-ALL) antigens . Selected B and T cell lymphomas were also tested for reactivity with the monoclonal antibodies OKT 3, OKT 4, OKT 6, OKT 8, OKT 11A, Leu-1, Leu-2a, Leu-3a, Leu-4 and Leu-7 . There were 26 B and 6 T lymphomas . Most B lymphomas were mu+ (81%), kappa+ (77%) and 31% were mu+ delta+ . One of the T lymphomas arose in a patient with antecedent follicular small-cleaved (B) cell lymphoma . The most accurate marker for characterizing the immunologic phenotype in NHL was the clonal excess of kappa+ or lambda+ cells . Neither Estandard, EAET, Egravity or T-LCL were consistently reliable as sole reagents in identifying T-cell lymphomas, their individual scores often being lower than those of monoclonal pan-T cell reagents . HLA-D (Ia-like) antigen was noted in 89% of B and 50% of T lymphomas . The corresponding values for c-ALL antigen were 12 and 33%, respectively . The comparative scores in T-lymphomas between OKT 4 and Leu-3a for "helper-inducer" (HE) cells and OKT 8 and Leu-2a for "suppressor-cytotoxic" (SU) cells were not uniformly consistent . Four T lymphomas had a mixed HE/SU cell phenotype, one was HE, and another SU . Anti-T reactivity was detected in the neoplastic follicles of six of seven follicular lymphomas . The percentage of anti-T reactive cells within positive neoplastic follicles was usually small (5-15%) and of the same order as that noted within reactive lymphoid follicles (5-30%) . High numbers (50-100%) of cells from five small lymphocytic B, three diffuse small cleaved cell B and six T cell lymphomas were also positive with one or more anti-T reagents, suggesting the presence of cross-reactive antigens that make phenotyping of lymphomas with monoclonal antibodies problematic . Reactivity with the monoclonal antibody Leu-7 (HNK-1), a putative NK-specific reagent, was seen in one of five B and three of five T lymphomas. J Membr Biol, 1983, 75(1), 65 - 72 Receptor capping in mouse T-lymphoma cells: a Ca2+ and calmodulin-stimulated ATP-dependent process; Bourguignon LY et al.; The roles that Ca2+, calmodulin, and ATP play in the redistribution of concanavalin A (Con A) binding sites on the surface of mouse T-lymphoma cells were examined . Membranes of cells labeled with fluorescein-conjugated Con A (Fl-Con A) were made permeable ("skinned") to ions and proteins by incubation in a solution containing no added Ca2+, 7 mM EGTA, and ATP . The intracellular ionic and protein concentrations could then be varied, and the degree of Con A receptor capping monitored simultaneously . A graded increase (9.0 to 30%) was found in the number of capped cells with increasing Ca2+ concentration from 10(-6)-10(-4.9) M . Increasing concentrations of trifluoperazine, chlorpromazine, and promethazine (1.5 x 10(-6) to 1.0 x 10(-4) M) in cell suspensions containing 10(-4) M Ca2+ produced graded inhibition of capping in the same order that the drugs bind to calmodulin . Removal of extracellular Ca2+ dissociated (reversed) some of the caps into patches, thus reducing their number (12%) . ATP was required for either capping or cap dissociation to occur . Addition of calmodulin (3.9 x 10(-8)-6.3 x 10(-7) M) to the cell suspension increased the Ca2+ sensitivity . These results provide direct evidence that capping of Con A receptors is a reversible process (i) regulated by intracellular Ca2+ concentrations, (ii) requiring ATP as an energy source, and (iii) susceptible to the influence of calmodulin . These findings are consistent with the hypothesis that the collection of surface receptor patches into cap structures is controlled by the interaction of actomyosin filaments, which in turn is regulated by a Ca2+-calmodulin-activated control system. J Immunol, 1983 Jan, 130(1), 203 - 8 Immunohistologic analysis of lymphoid infiltrates in primary Sjogren's syndrome using monoclonal antibodies; Adamson TC 3rd et al.; The characterization of lymphocytes infiltrating salivary glands in patients with primary Sjogren's syndrome (1 degree SS) yields insights to disease pathogenesis that are not revealed by studies of the corresponding peripheral blood lymphocytes (PBL) alone . We analyzed salivary gland lymphocytes (SGL) and PBL in 14 patients with untreated 1 degree SS using monoclonal antibodies that detect T cells, T cell subsets, B cells, and antigens associated with lymphocyte activation . A four-step biotin-avidin immunoperoxidase technique was used for salivary gland frozen sections; cell suspensions and PBL were stained cytofluorographically . A predominance of T cells (Leu 1 = L17F12; Leu 4 = OKT3) was found in SGL (greater than 75%) and PBL (76 +/- 9%) with the majority belonging to the Leu 3a (OKT4) subset . A minority of B cells (anti-delta, -kappa, -lambda) was present in both SGL and PBL; however, a subset of B cells defined by monoclonal antibody B532 was present in SGL (5 to 20%) but was absent from PBL . An increased prevalence of activation antigens (Ia; OKT10) was found on SGL T cells (greater than 50% positive) compared to PBL T cells (less than 15% positive) . These studies demonstrate that specific antigenic markers on lymphocytes at the site of inflammation in 1 degree SS differ significantly from those of the corresponding PBL . These differences emphasize that theories of disease pathogenesis of 1 degree SS must include studies on SGL. Acta Physiol Scand Suppl, 1983, 522, 9 - 18 Intracerebral grafting of neuronal cell suspensions . II . Survival and growth of nigral cell suspensions implanted in different brain sites; Bjorklund A et al.; Dissociated dopamine-rich cell suspensions were prepared from the ventral mesencephalon of rat embryos and injected in one or several sites in striatal and non-striatal regions in the dopaminergically denervated brain of adult rats . While the grafts survived well in all sites, the dopamine fibre outgrowth was markedly different depending on whether the grafts occurred in an area normally innervated by the mesencephalic dopamine neurones (i.e . neostriatum or nc . accumbens) or in areas not normally innervated by these neurones (i.e . parietal cortex, lateral hypothalamus or substantia nigra) . Moreover, in grafts placed at different sites along the trajectory of the nigrostriatal pathway the outgrowing fibres remained confined to the graft, and there was little evidence that the implanted neurones could elongate their axons along the pathway of the nigrostriatal tract to reach the striatum from a distance . Thus, the intracerebral suspension grafts provided efficient reinnervation of a denervated target only when placed in the immediate vicinity of the target area . The results of multiple graft placements indicate that a relatively complete restoration of a lost innervation should be possible to achieve in large areas of the brain, such as the striatal complex, with the suspension grafting technique. Acta Physiol Scand Suppl, 1983, 522, 67 - 75 Intracerebral grafting of neuronal cell suspensions . VIII . Survival and growth of implants of nigral and septal cell suspensions in intact brains of aged rats; Gage FH et al.; Neuronal cell suspensions prepared from the ventral mesencephalon and the septal-diagonal band area of rat embryos were implanted into the depth of the intact neostriatum or hippocampus of 21-23 month old female rats . Graft survival, assessed 3-4 months after grafting, was comparable to that seen in our previous studies of young adult recipients . Fibre outgrowth into the host brain was evaluated in animals which were subjected to lesions of the intrinsic nigrostriatal or septohippocampal system 6-10 days before killing . Dense dopamine fibre outgrowth was seen within a zone of up to about 1 mm radius around the nigral implants, and dense growth of acetylcholine esterase (AChE) positive fibres occurred up to about 2 mm away from the septal implants . The overall magnitude of fibre outgrowth was less than that generally seen in previously denervated targets in young adult recipients, but it appeared to be as extensive as in young recipients when the grafts are placed in non-denervated targets . The distribution of the AChE-positive fibres from the septal implants in the host hippocampus suggested that the pattern found in the non-denervated target of the aged recipients was more diffuse, and partly different, from normal, and that age-dependent synapse loss in intrinsic connections may influence the patterning of the graft-derived innervation. Acta Physiol Scand Suppl, 1983, 522, 59 - 66 Intracerebral grafting of neuronal cell suspensions . VII . Recovery of choline acetyltransferase activity and acetylcholine synthesis in the denervated hippocampus reinnervated by septal suspension implants; Bjorklund A et al.; The time-course and magnitude of fibre outgrowth from septal suspension grafts injected into the previously denervated hippocampal formation was monitored by measurements of choline acetyltransferase (ChAT), and the activity of the grafted neurons was assessed by measurements of {14C}acetylcholine (ACh) synthesis from {14C}glucose in vitro . Graft-derived ChAT activity was barely detectable 10 days after grafting, but increased sharply between 10 days and 1 month in the areas of the hippocampus located close to the septal implants . By 6 months ChAT activity was restored to near normal levels in all segments of the previously denervated hippocampus . The overall hippocampal {14C}ACh synthesis was also restored to normal levels in the grafted animals, and estimates of the ACh turnover rate suggested that the transmitter machinery of the newly established "septo-hippocampal" connections operated at a rate similar to that of the intrinsic septohippocampal pathway . The intrahippocampal septal suspension grafts, similar to the intrastriatal nigral grafts, thus seem to be capable of maintaining function at a relatively "physiological" level despite their abnormal positions. Acta Physiol Scand Suppl, 1983, 522, 49 - 58 Intracerebral grafting of neuronal cell suspensions . VI . Survival and growth of intrahippocampal implants of septal cell suspensions; Bjorklund A et al.; The survival and growth of intrahippocampal septal suspension grafts were investigated by acetylcholine esterase (AChE) histochemistry in animals with lesions of the intrinsic septohippocampal cholinergic pathways . AChE was demonstrable in the grafts after the first postoperative week, and AChE-positive fibres were seen to extend into the host hippocampus by 3 weeks . Rapid fibre outgrowth occurred between 3 weeks and 3 months after grafting, and continued at a slower rate thereafter . By 6 months a fairly complete reinnervation of the initially denervated hippocampus was achieved in most specimens, and this persisted at 14 months, the longest postoperative time analysed . A comparison between the development of the AChE-positive neurones in the suspension grafts with that seen during ontogeny in situ suggested that the grafted neurones lagged behind normal development by at least 1 week . Similar to our previous observations on septal grafts implanted as solid tissue pieces, the pattern of the newly-formed AChE-positive innervation in the host hippocampal formation, established from the septal suspension grafts, was remarkably similar to that of the normal AChE-positive septal innervation . This pattern became established as soon as the graft-derived fibres first grew in, suggesting that the ingrowing axons extended and ramified preferentially into those hippocampal subfields which normally receive an AChE-positive innervation from the septal-diagonal band area. Acta Physiol Scand Suppl, 1983, 522, 1 - 7 Intracerebral grafting of neuronal cell suspensions . I . Introduction and general methods of preparation; Bjorklund A et al.; The steps involved in the grafting of mesencephalic and septal embryonic tissue in the form of dissociated cell suspensions are described in detail . This includes dissection of the donor embryos, incubation in trypsin, mechanical dissociation, and stereotaxic injection into the brains of adult recipient rats . Some of the technical problems and limitations are discussed. Leuk Res, 1983, 7(6), 735 - 46 ALL masquerading as AUL; Greaves MF et al.; Of 597 cases of acute leukaemia in adults (greater than 16 years) seen at St . Bartholomew's Hospital, London, between May 1973 and January 1982, 412 were diagnosed as AML, 103 as ALL and 58 as Philadelphia chromosome positive blast crisis of CML (13 presenting as acute leukaemia and 45 having a prior chronic phase) . The remaining 24 cases were considered to be acute undifferentiated leukaemia . Twenty-one of the latter were investigated using a panel of immunological markers at diagnosis and/or retrospectively using frozen cell suspensions . Eighteen out of 21 were shown to have a predominantly 'lymphoid' phenotype which comprised 12 cases of common ALL (two of whom were Ph1 positive), three cases of null-ALL, one case with a probable early thymic phenotype, and two cases with a monoclonal B lymphoblast phenotype . One 'common ALL' and one 'null-ALL' had a significant proportion of pre-B (cytoplasmic mu chain+) cells . One other case reacted with anti-myeloid sera . Leukaemic blasts from two patients were unreactive with all markers tested . No cases of glycophorin positive erythroleukaemia or anti-platelet (glycoprotein I) positive leukaemia were detected . These observations suggest that the overwhelming majority of acute leukaemias have an identifiable affiliation to the lymphoid or myeloid lineages and that patients diagnosed haematologically as 'AUL' might benefit by therapy appropriate for their leukaemic cell type. Cell Tissue Res, 1983, 231(2), 313 - 23 Characterization of the population of phagocytic cells in thymic cell suspensions . A morphological and cytochemical study; Duijvestijn AM et al.; Rat thymic phagocytic cells were characterized in vitro using various light- and electron-microscopical techniques . Thymic cell suspensions were mechanically prepared and enriched for non-lymphoid cells, which were predominantly phagocytic and of three types . Type I showed acid phosphatase (APh) activity in small granules dispersed throughout the cytoplasm and were mostly Ia antigen-positive, although the Ia membrane label varied in intensity and distribution among individual cells . Only a few cells had endogenous peroxidase activity . The type-I cells could not be clearly distinguished morphologically from type-II or -III cells, and most likely comprise precursors of both these cell types . Type-II were large pale cells with many slender cell processes . These cells had APh activity centrally positioned, were strongly positive for Ia on the cell membrane and were negative for endogenous peroxidase . The cytoplasm frequently contained Birbeck granules, which unequivocally classifies these cells as the in vitro equivalent of the interdigitating cells present in the medullary area of the thymus in situ . Type-III cells were rounded with a smooth or ruffled cell membrane and contained vacuoles and many phagolysosomes . They were strongly positive for APh which was present throughout the cytoplasm . About 50% of these cells were positive for endogenous peroxidase in a pattern resembling resident macrophages . The cells were negative for Ia antigens . Type-III cells mostly likely represent the macrophages found in the cortical area of the thymus. Cancer Drug Deliv, 1983, 1(1), 43 - 58 Inhibition of liver metastases of M 5076 tumor by liposome-entrapped adriamycin; Mayhew E et al.; The toxicity and therapeutic efficacy of free adriamycin (AM) and AM entrapped in standardized liposomes (AM-MLV) were evaluated in normal mice and in mice bearing M 5076 murine tumor, which metastasizes to the liver after i.v . and s.c . transplants of tumor cell suspensions . Acute and chronic toxicity to AM could be reduced by drug encapsulation in liposomes . The data indicated that at approximately equitoxic doses of free AM (10 mg/kg) and AM-MLV (greater than 20 mg/kg), the increase in survival times of mice transplanted i.v . with tumor cells were 25% and 100%, respectively . Furthermore, only in the AM-MLV-treated mice were long-term survivors observed . In contrast AM-MLV were equally effective as free AM in mice transplanted s.c . with tumor cell suspensions . AM-MLV, however, were more effective than free AM against liver metastases in mice bearing s.c . tumor, indicating differential antitumor activities against the same tumor type growing at different locations in the same animals. Clin Exp Metastasis, 1983 Jan-Mar, 1(1), 71 - 81 Treatment of artificially-induced pulmonary metastases with fractionated doses of vincristine and/or radiation therapy; Grdina DJ et al.; The cytotoxic effects in vivo of vincristine (VC), radiation, or both modalities in combination on murine fibrosarcoma (FSa) cells grown as pulmonary tumors were determined . Fourteen days following the i.v . injection of viable FSa cells, recipient mice developed between 100 and 150 visible pulmonary nodules . At that time, tumor-bearing animals were exposed to either single or combined modality treatments, as well as single and fractionated dose regimens . Animals were sacrificed 1 hour after the last treatment . Tumor nodules were excised and made into a single cell suspension and separated on the basis of cell size by centrifugal elutriation . Flow microfluorometry (FMF) was used to determine the cell-cycle parameters and the relative synchrony of the separated populations, as well as the percentage contamination by normal diploid cells in each of the tumor cell populations . Known numbers of viable cells from each elutriator fraction were injected into recipient mice to determine their colony-forming efficiency (CFE) . Surviving fractions were determined by comparing the CFEs of treated FSa cells from each of the separated elutriator fractions with those of appropriate untreated controls . Following a single dose of VC (1 mg/kg), populations of cells enriched in late S and G2 + M were the most sensitive . However, following the administration of five doses (0.25 mg/kg each) over a 24 hour period, populations of cells most enriched in G1 cells exhibited the lowest percentage of survivors . A single dose of radiation (1000 rad) was most effective in killing S-phase cells . When administered in five fractions (250 rad per fraction), each separated by a 6 hour interval, no phase-specific sensitivity was observed . The combination of both modalities exhibited a marked schedule dependence, with a single dose (1000 rad) of radiation followed by five doses of VC (0.25 mg/kg) being the most effective treatment protocol observed. Acta Physiol Scand Suppl, 1983, 522, 39 - 47 Intracerebral grafting of neuronal cell suspensions . V . Behavioural recovery in rats with bilateral 6-OHDA lesions following implantation of nigral cell suspensions; Dunnett SB et al.; Bilateral 6-hydroxydopamine-induced lesions of the ascending forebrain dopamine neurones induce a behavioural syndrome in rats which includes profound aphagia, adipsia, akinesia and bilateral sensorimotor neglect . Such animals will die unless maintained by intragastric feeding . Three experiments are reported in which we have attempted to ameliorate this syndrome with single or multiple placements of nigral cell suspensions into the forebrains of rats with bilateral dopamine depletions . Although the grafts were efficient in reversing the sensorimotor and akinetic impairments, and produced a significant increase in eating, the grafted rats remained hypophagic and adipsic . The results indicate that although many components of the bilateral dopamine denervation syndrome can be reversed by intrastriatal nigral suspension grafts, the severe eating and drinking deficits remain unameliorated. Acta Physiol Scand Suppl, 1983, 522, 29 - 37 Intracerebral grafting of neuronal cell suspensions . IV . Behavioural recovery in rats with unilateral 6-OHDA lesions following implantation of nigral cell suspensions in different forebrain sites; Dunnett SB et al.; Single and multiple implants of nigral cell suspensions were grafted to the forebrains of rats with unilateral 6-hydroxydopamine-induced dopamine denervations . Control lesions alone induced a marked behavioural asymmetry, as assessed by amphetamine- and apomorphine-induced rotation, sensorimotor tests and side bias in an unbaited T-maze, and the animals were hyperactive to a low dose of apomorphine . Single suspension placements into different denervated striatal regions were capable of reversing the behavioural asymmetries dependent upon the specific placement for each test . Multiple suspension grafts were capable of reversing all behavioural asymmetries, and additionally abolished the supersensitive hyperactivity to apomorphine . By contrast, single suspension grafts placed into the substantia nigra or lateral hypothalamus had no detectable effect on any functional measure . The results indicate that nigral suspension grafts can be at least as effective as solid grafts in reversing the functional deficits induced by dopamine denervation, provided that placements are selected within appropriate dopamine terminal regions of the forebrain (e.g . caudate-putamen or nucleus accumbens). Scan Electron Microsc, 1983, (Pt 4), 1963 - 72 The application of scanning electron microscopy to cells in culture: selected methodologies; Allen TD; Cell culture is one of the most widely used techniques in modern biology . As a result, morphology of culture systems at the ultrastructural level is also becoming more widespread . Whilst offering an optimum in terms of fixation accessibility, cells in tissue culture can present problems in terms of handling for scanning electron microscopy, particularly when they are grown on, or in semi-solid media, or on gels e.g . collagen . The examination of cultured cell suspensions or mixed cell populations may also require careful handling to produce meaningful results in terms of surface morphology and cellular interaction . Cells specifically cultured on carbon films can also be used for information of internal cell structure as well as surface topography, often simultaneously, if a suitable imaging system is available . This communication reviews a wide spectrum of experimental manipulations of cultured material to provide an introduction to the gathering of morphological information from material in tissue culture. Jpn J Physiol, 1983, 33(4), 635 - 50 Rate of CO2 diffusion in the human red blood cell measured with pH-sensitive fluorescence; Niizeki K et al.; The diffusion rate of CO2, into and out of the red cell, was measured by using a stopped flow method with pH-sensitive fluorescence of 4-methylumbelliferone . A red cell suspension of 15% hematocrit with the PCO2 of 8 Torr (or 65 Torr) was mixed with the same amount of saline solution having 65 Torr (or 8 Torr) . Carbonic anhydrase was added to the external solution at a concentration of 20 mg/100 ml in order to accelerate the hydration and dehydration reactions, so that the PCO2 change in the fluid could be observed instantaneously through pH . In the inward diffusion PCO2 showed a large change, suggesting a lack of HCO3- shift across the red cell membrane . In the outward diffusion, however, the PCO2 change was smaller, suggesting that H+ ions produced in the external solution by CO2 hydration were rapidly buffered by the red cell . The half-times of the inward and outward diffusions were, on an average, 0.08 and 0.13 sec, respectively . The results of the simulation revealed that the above difference in half-times was attributed to the difference in slope between the two dissociation curves with and without the HCO3- shift . The diffusion rate was almost constant and remained independent of the direction of CO2 flux . That is, at a low pH range the permeation of H+ ions across the red cell membrane was much faster than the diffusion rate of CO2. Vox Sang, 1983, 45(3), 217 - 23 Red cell suspensions in SAGM medium . Further experience of in vivo survival of red cells, clinical usefulness and plasma-saving effects; Hogman CF et al.; Red cells depleted of buffy coat and more than 90% of the plasma were suspended and stored in a medium composed of sodium chloride, adenine, glucose and mannitol (SAGM) . The 24-hour posttransfusion survival of 51Cr-labeled red cells was 83.5 +/- 5.3% (n = 4) after storage for 35 days and 77.4 +/- 4.7% (n = 6) after 42 days . No abnormal in vivo hemolysis occurred as judged from posttransfusion haptoglobin consumption studies . No abnormal body temperature elevation was found at continuous pertransfusion recordings . The frequency of febrile or urticarial transfusion reactions was 0.19% as compared to 0.68% during a whole-blood transfusion period . Since a mean of 280 ml of plasma can be collected from each blood unit the plasma-saving effects of the system are considerable . Favorable large-scale clinical experience is reported. Immunol Rev, 1983, 73, 35 - 51 Natural cytotoxicity: early killing of allogeneic lymphocytes in rats; Heslop BF et al.; In many strain combinations among inbred rats, intravenously injected 51Cr-labelled lymphocytes are destroyed in substantial numbers by unsensitized allogeneic hosts . Destruction of cells (referred to as natural cytotoxicity (NC)) occurs within a few hours of injection, and is characterised by a decreased accumulation of radioactivity in the lymph nodes and increased renal excretion of label by allogeneic hosts, as compared with the distribution of label in syngeneic recipients of the same cell suspension . An intact spleen is necessary for killing . The level of NC expressed is consistent for a given donor-host combination . Using arbitrary criteria to compare the levels of NC expressed by different donor-host combinations among inbred rats, 13 of 95 strain combinations have been shown to express high NC, 63 intermediate NC and 19 low NC . The level of NC expressed cannot be correlated with the extent to which donor and host differ in respect of known MHC genes . Segregation analysis has shown high NC to be controlled by at least 2 independently segregating genes, one of which is MHC-linked . It is possible to weaken or abrogate NC by the neonatal injection of bone-marrow cells from the donor strain, and to reverse this reduced reactivity by the injection of host strain lymphocytes . The substitution of either the donor (P1) or the host (P2) by the P1 X P2)F1 hybrid reduces or eliminates NC in strain combinations normally expressing high NC . It is currently uncertain whether NC can be augmented . In the single strain combination in which maturation has been studied, NC becomes evident during the 4th week of life and attains adult levels during the 6th-7th weeks . NC is at least partially radio-sensitive . Two groups of reactivities appear to be related to NC: (i) those which have been identified in the context of aberrant lymphocyte homing, and for which allogeneic lymphocytes are the targets; (ii) the group of natural resistance systems which includes NK cells, and whose reactivity is directed against a variety of other target cells. Ophthalmic Res, 1983, 15(2), 61 - 7 Aqueous humor and serum IgE antibody in experimental ocular Onchocerca infection of guinea pigs; Donnelly JJ et al.; Infection of inbred Strain 2 guinea pigs by subcutaneous or intradermal injection of fresh or cryopreserved living Onchocerca lienalis microfilariae, followed by a challenge intracorneal infection of microfilariae, resulted in serum and aqueous IgE antibody and in significant corneal inflammation . Systemic or intraocular infections given separately were not sufficient to elicit IgE antibody or ocular inflammation . When intravenous transfer of pooled spleen cell suspensions from systemically infected donors to normal syngeneic recipients was substituted for the course of systemic infections, a subsequent intracorneal challenge of cell transfer recipients with microfilariae produced serum and aqueous IgE antibody . Administration of diethylcarbamazine citrate to infected animals following the intracorneal challenge resulted in increased serum IgE antibody and in increased corneal inflammation. Dev Neurosci, 1983-84, 6(3), 137 - 51 Intracerebral grafting of embryonic neural cells into the adult host brain: an overview of the cell suspension method and its application; Gage FH et al.; An overview is presented of general principles for intracerebral grafting of embryonic brain tissue to the adult mammalian brain . Special reference is made to the development and use of the dissociated neuronal cell suspension method . Examples are drawn primarily from experiments where embryonic ventral mesencephalon is transplanted to adult striatum and embryonic septal-diagonal band area is transplanted to the hippocampal formation . Results related to the cell viability in vitro and in vivo and to axonal outgrowth are the main focuses of this overview. Arch Immunol Ther Exp (Warsz), 1983, 31(4), 449 - 57 Antimonocyte serum . Preparation and characterization; Goscicka T et al.; Cell suspensions enriched with monocytes were obtained from the blood of Vietnam normal pig and rabbits injected with avirulent Welshimer strain of L . monocytogenes by velocity sedimentation on BSA gradient and separation on Ficoll-Triosil gradient . They were used for immunization of rabbits and a sheep, respectively . The antisera specific for monocytes (RAMS and SAMS) were obtained by scrupulous absorption with lymphocytes and granulocytes. Neoplasma, 1983, 30(6), 691 - 700 Electrophoretic mobility profiles of mouse leukemias . II . Electrophoresis of thymic lymphoma, myeloid leukemia and reticulum sarcoma cells; Bubenikova D et al.; Electrophoretic mobility of cells from 21 primary mouse leukemias was investigated and compared with that of various normal mouse reference cells . Six thymic lymphomas, nine reticulum cell sarcomas, five myeloid leukemias and one stem-cell leukemia were examined . The mean AEM of cells from the group of primary thymic lymphomas (1.13 microns s-1 V-1 cm) was similar to that of reticulum cell sarcomas (1.15 microns s-1 V-1 cm) and significantly lower than that of the myeloid leukemias (1.20 microns s-1 V-1 cm) . Since the examined cell suspensions were prepared from leukemic lymph nodes, the analysis was performed to investigate the possible admixture of normal LNC in the cell populations . Electrophoretograms of normal and leukemic lymph nodes were compared and the AEM of cells from leukemic lymph nodes was considered separately for two cell populations, one corresponding in size to normal LNC (6-9 microns in diameter) and the other to leukemic blast cells (10-16 microns in diameter) . In the 6-9 microns cell subpopulations from leukemic lymph nodes, electrophoretically slow cells corresponding to B LNC were almost totally depleted (1%); also electrophoretically fast cells with the mean AEM of T LNC were fewer (45-57%) than in normal LNC populations . The leukemic cells 10-16 microns in diameter displayed mean AEM of 1.09 (thymic lymphomas), 1.12 (reticulum cell sarcomas) and 1.21 (myeloid leukemia) micron s-1 V-1 cm . The mean AEM of blast cells from thymic lymphomas and reticulum cell sarcomas was not significantly different; it was similar to that of blast cells prepared from normal mouse thymus (1.09 microns s-1 V-1 cm) on a density gradient . In contrast, the 10-16 microns cell populations from lymph nodes of mice with myeloid leukemias were significantly faster than blast cells from thymic lymphomas and reticulum cell sarcomas. Ann Med Interne (Paris), 1983, 134(5), 395 - 410 {Blood hyperviscosity syndromes . Classification and physiopathological understanding . Therapeutic deductions}; Larcan A et al.; Blood has a number of rheological properties which partially determine flow, especially at capillary level, and its capacity to deliver oxygen . It is non-Newtonian, pseudoplastic, thixotropic and viscoelastic . Viscosity can be studied with different types of viscosimeters (coaxial cylinder or capillary viscosimeters) . It can be defined by the ratio of stress of deformation to rate of deformation . Viscosity depends on macrorheological parameters: hematocrit, serum proteins, especially fibrinogen and globulins, and also on microrheological parameters: degree of aggregation and red blood cell deformability . Viscosity rises when the temperature falls and decreases with the radius of the tube through which the blood flows (Fahraeus-Linqvist effects) . Blood viscosity is studied clinically at different temperatures, and, above all, at different rates of deformation by carefully recording the hematocrit . Plasma viscosity, fibrinogen, albumia and immunoglobulin levels, the viscosity of blood cell suspensions in normal saline must also be taken into consideration . Special investigations (rheoscopy, filtrability) provide information about red cell aggregation and deformability . Hyperviscosity syndromes are observed with: --raised hematocrit (polycythemia and pseudopolycythemia), --conditions with raised serum proteins or changes in their composition (especially hyperfibrinogenemia, raised immunoglobulins, low albumin levels); inflammatory syndromes, dysglobulinemias (Fahey's syndrome of plasma hyperviscosity), --low temperature (hypothermia), --increased red cell aggregability (shock, fat embolism), --reduced red cell deformability due to various congenital and acquired conditions (sickle cell anemia, renal failure, hyperlipoproteinemia, thrombosis, diabetes) . Conversely, hypoviscosity may occur with a low hematocrit, hypoproteinemia, hypofibrinogenemia, and hyperthermia . Increased viscosity results in a slowing of blood flow, stagnation of its constituents and in ischemia . Therapeutic interventions may be considered on the different components of the hyperviscosity syndrome: hemodilation, plasmapheresis, dispersion of aggregants, agents acting on red cell deformability. Adv Exp Med Biol, 1983, 159, 419 - 34 Cellular oxygen utilization and radiation response of V-79 spheroids; Durand RE; Chinese hamster V-79-171 cells, when placed in stirred suspension cultures, spontaneously grow as spherical multicell aggregates (spheroids) which eventually contain many thousand tightly-packed cells . These spheroids thus provide a valuable model for the study of oxygen transport, since oxygen concentration at the spheroid periphery can be fairly precisely controlled in the stirred suspension, and the consequences of oxygen diffusion inward through the tissue-like mass can be determined experimentally and compared with theoretical calculations . As in human tumors, appearance of central necrosis can be correlated with severe hypoxia . Additionally, since severely hypoxic cells are considerably more resistant to radiation than are oxygenated cells, determination of the fraction of hypoxic cells by their radioresistance provides a noninvasive technique for monitoring respiratory processes . Using this approach, we have found an excellent correlation between the rate of cellular oxygen utilization by a single cell suspension and the net radio-sensitivity of multicell spheroids when treated with modulating agents, varying from direct control of metabolic activity by changing the ambient temperature, to less direct effects on cellular oxygen consumption induced by exposure of cells to nitroheterocyclic radiosensitizers, chemotherapeutic agents, anesthetics, antibiotics, and even cell growth factors including insulin . Our data from these studies indicate that, at least in the simplistic spheroid system where oxygen delivery to the internal cells is a direct function of the respiratory activity of the external cells, control of cellular oxygen utilization is a convenient and effective method of controlling the net radiosensitivity. Adv Exp Med Biol, 1983, 159, 399 - 417 A method to measure the radio and chemosensitivity of human spheroids; Carlsson J et al.; A method based on the spontaneous outgrowth of cells from spheroids was tested . Different outgrowth patterns were seen depending on the types of spheroids and on the radiation or drug doses . The method allowed dose-effect relations to be determined . Spheroid survival was defined as when the outgrowing monolayers contained at least thousand cells within five weeks . The method was used as an alternative to cloning of isolated single cells . The glioma and osteosarcoma spheroids could not be disintegrated to single cell suspensions since they resisted enzymatic and mechanical treatments for cell separation . Detection of differences in radio and chemosensitivity between different types of spheroids of human origin might be valuable for the understanding of the large variations in therapeutical response often seen between different types of tumors. Microsc Acta Suppl, 1983, 6, 21 - 7 {Determination of a significant cell count for positive diagnosis in gynecologic suspension preparations and possible consequences for the analysis of automated preparations}; Schwarz G et al.; Monolayer preparations used in automated cytology are generated from gynecologic cell suspensions . The suspension-derived preparations (s.p.) show some peculiarities compared with conventional cytologic smears . One important feature of the s.p . is a distribution of cells mainly by chance . Therefore it seems to be possible to determine a cell sample size in minimum needed for cytologic diagnosis . In a blind test the needed cell sample size was determined by counting the cells in the microscopic fields of vision (ocular 12,5 x, objective 10 x, phi of the field of vision 2 mm) step by step until it was possible to classify the specimen (diagnosis 1) . To be on the safe side (personal safety requirement) some further cells were assessed (diagnosis 2) . We used s.p . from 50 non-suspicious women and 50 women with invasive squamous cell carcinoma of the uterine cervix and its precursors . To recognize strong positive cases (severe dysplasia to invasive carcinoma) only about 600 cells are needed (mean: 150/147 cells) . The most cells (about 1200 cells) are required in negative cases and cases of mild to moderate dysplasia (mean: 293/236 cells) . The highest personal safety requirement was found in cases of mild to moderate dysplasia (311% compared with a mean sample size of 236 or 100%) . The results support such approaches in automated cytology which analyze only some hundreds or about 1000 cells with high resolution. Arch Dermatol Res, 1983, 275(2), 130 - 3 Isolation of a viable eccrine sweat gland by dispase; Okada N et al.; Dispase was used to obtain viable eccrine sweat glands from human skin in an intact shape . The full thickness of human skin was soaked in a solution of dispase in Eagle's minimum essential medium at a concentration of 500 units/ml and kept in a refrigerator at 4 degrees C for 24 h . The epidermal sheet with its appendages could then be easily separated from the dermis by lifting the epidermis with fine forceps . Electron-microscopic observation revealed that the eccrine sweat gland was completely separated froM the dermis at the basement membrane zone . The isolated epidermal sheet was scarcely dissociated by mechanical agitation in the presence of Ca2+ and Mg2+ ions . The eccrine sweat gland was cut away from the epidermis by using microscissors under a stereomicroscope . A cell suspension of the isolated eccrine sweat glands was obtained after trypsinization . The cells remained more than 90% viable up to 48 h in the culture medium . The obtained viable eccrine sweat glands will be useful for the study of the biology of sweating. Pathol Biol (Paris), 1983 Jan, 31(1), 49 - 51 {Test of human basophil degranulation . The interpretation and analysis of variability factors in the absence of antigen}; Mordelet-Dambrine M et al.; The human basophil degranulation test (TDBH) is performed using a concentrated cell suspension enriched for polymorphonuclear basophils . This preparation is placed in wells on a glass slide with an allergen solution of decreasing concentration . After incubation the cells are fixed in the wells and stained with toluidine blue . Preparations containing fewer metachromatic basophils than in control preparation of the same cell suspension without antigen contain degranulated basophils and in this way a degranulation index can be calculated . By considering the variability in the number of basophils between duplicate control wells from the same cell suspension, it can be shown that the test can be considered to be positive only if the number of degranulated basophils equals or exceeds 50% of the total number of basophils . This variance can be attributed to the subjectivity of the reader, and to differences in the differential cell counts from well to well . On the other hand, the presence of atopic allergy had no effect on the basophil counts. Avian Dis, 1983 Jan-Mar, 27(1), 21 - 35 Application of enzyme-linked immunosorbent assay for detecting antibody to Mycoplasma gallisepticum infections in poultry; Ansari AA et al.; An enzyme-linked immunosorbent assay (MYCO-ELISA) was developed to detect antibodies to Mycoplasma gallisepticum (MG) in chicken sera . The assay was standardized in terms of optimum antigen concentration, serum dilution, conjugate dilution and incubation temperature, and time . The MYCO-ELISA antigen was prepared from MG whole bacterial cell or its disrupted cell suspension . Both preparations showed strong affinity for binding or adsorbing to the surface of polystyrene wells of the microtiter plate . The MYCO-ELISA was more sensitive than the hemagglutination-inhibition test . However, cross-reactions were observed with sera from M . synoviae (MS)-infected birds. J Immunol Methods, 1983, 56(1), 117 - 24 Comparison of the sensitivity of the protein A plaque assay and the immunofluorescence assay for detection of immunoglobulin producing cells; Van Oudenaren A et al.; This paper reports a comparative study on the sensitivity of the protein A plaque assay and the cytoplasmic immunofluorescence assay for detection of immunoglobulin (Ig) producing cells in cell suspensions of murine lymphoid organs . The protein A plaque assay was found to detect as many or several times more Ig producing cells than the immunofluorescence assay, depending on the age and antigenic load of the mice, and upon the Ig class and organ studied. Diagn Immunol, 1983, 1(3), 142 - 9 The application of monoclonal antibodies to the characterization and diagnosis of lymphoid neoplasms: a review of recent studies; Knowles DM 2nd et al.; Twenty-three T-cell neoplasms were divided, according to their reactivity with the OKT monoclonal antibodies as follows: Fourteen neoplasms of diverse histopathology expressed the OKT3+ OKT4+ phenotype, commonly associated with the helper T-cell subset; seven histologically similar lymphoblastic neoplasms expressed diverse phenotypes consistent with various stages of intrathymic differentiation and two neoplasms expressed the uncommon OKT3+ OKT10+ phenotype . Thus, T-cell neoplasms are divisible into phenotypes that correspond to normal stages of T-cell differentiation and functionally distinct T-cell subsets . Benign and malignant lymphoid cells were investigated in cell suspension and in cryostat tissue sections for their reactivity with OKB1, OKB2, OKB4, and OKB7, monoclonal antibodies known to detect distinctive B lymphocyte antigens . Fetal liver pre-B cells, cases of pre-B acute lymphoblastic leukemia, and common-type acute lymphoblastic leukemia were OKB2+ but unreactive with the other OKB antibodies . All mature lymphoid tissue B cells and 47/47 surface immunoglobulin (SIg)-positive B-cell neoplasms were OKB2+ . Interfollicular, follicular center, and many, but not all, mantle zone B cells were OKB1+ OKB7+ . Follicular center B cells were OKB4+ but mantle zone and interfollicular B cells were OKB4- . 45/47 SIg+ B-cell neoplasms were OKB1+ OKB4+ . 45/46 SIg+ B-cell neoplasms were OKB7+ . Benign and myeloma plasma cells were OKB- . T-cell neoplasms were OKB2- OKB4- but were occassionally OKB1+ and OKB7+ . The OKB antibodies appear to detect distinctive antigens that may be expressed at different stages of B-cell differentiation. Acta Physiol Scand Suppl, 1983, 522, 19 - 28 Intracerebral grafting of neuronal cell suspensions . III . Activity of intrastriatal nigral suspension implants as assessed by measurements of dopamine synthesis and metabolism; Schmidt RH et al.; The activity of intrastriatal grafts of nigral cell suspensions has been monitored biochemically, using radioenzymatic assays of dopamine, its major acidic metabolite, DOPAC, and DOPA accumulation after DOPA-decarboxylase inhibition . Implants of 4-9 microliter of nigral cell suspension restored striatal DA levels by an average of 13-18%, with the highest individual values reaching about 50% of control . DOPAC was restored from about 5% in the lesioned controls to about 20% of normal in the grafted animals . The DOPAC: DA ratios and the DOPA accumulation measures indicated that the grafted DA neurons were spontaneously active and that the transmitter turnover rate was on the average some 50-100% higher than the intact intrinsic nigrostriatal DA neurones . These results thus provide evidence that the intrastriatal nigral suspension grafts are capable of restoring dopaminergic neurotransmission in the previously denervated striatum. Breast Cancer Res Treat, 1983, 3(1), 15 - 22 A comparison of methods for the production of monodispersed cell suspensions from human primary breast carcinomas; Besch GJ et al.; Production of monodispersed cell suspensions from primary human breast tumors is difficult due to the predominant stromal composition of most breast tumors . Our studies were designed to optimize dispersion of breast tumors of known stromal content and histopathology . In a first series of experiments three enzymatic protocols were compared to disperse minced tissue: (A) treatment with collagenase (2 mg/ml) in the presence of 5% serum for 24 hours; (B) treatment with collagenase (6 mg/ml) and DNase (0.002%) in 10% serum for 3 hours; (C) treatment with collagenase (2 mg/ml) for 3 hours followed by pronase (0.075%) for 1 hour . Protocol A produced better cell yields than B or C for all tumors tested . The monodispersed cells were suspended in a 0.3% semi-solid agar with alpha modified Eagles medium (alpha MEM), 10% serum, and selected hormones, then layered over similarly enriched 0.5% semi-solid agar . The cells prepared by protocol A had a higher plating efficiency and larger average colony size than B or C . In a second series of experiments, protocol A was repeated and compared to two additional procedures: (D) treatment with collagenase (2 mg/ml) and hyaluronidase (1 mg/ml) in the presence of 5% serum for 24 hours; and (E) mechanical disaggregation . Protocol D exhibited a small but significant negative difference from A, while E was the least efficient in producing viable monodispersed cells from the tumors . All enzymatically monodispersed cells produced clonal growth in our agar system . However, mechanically dispersed cells gave growth in only 4 of 7 tumors . Protocol A, in addition to yielding the highest number of viable cells per gram of tissue, gave the highest plating efficiency of all protocols tested. Cell Tissue Res, 1983, 231(2), 457 - 61 Scanning electron microscopy of pure Kurloff cell suspensions . Observation of an extrusion process; Landemore G et al.; Scanning electron microscopy has been used to examine suspensions of Kurloff cells, which are present only in guinea pig . The cells are round with a surface characterized by uniformly distributed short stubby microvilli and some ridges . Some cells show one or more pores surrounded by a smooth margin, others a smooth globular expansion about 10 microns in diameter which may correspond to a Kurloff body undergoing exocytosis . The Kurloff body is released into the medium where it can exist freely . The surface of the free body and of the expansion display the same smooth appearance . Although the nature of the Kurloff cell remains unknown, this study provides further information concerning its morphology and describes an extrusion process not observed previously. Avian Dis, 1983 Jan-Mar, 27(1), 271 - 82 Studies of reticuloendotheliosis virus-induced lymphomagenesis in chickens; Fadly AM et al.; Seventy-three percent of chickens inoculated with the chick syncytial strain of reticuloendotheliosis virus (REV) at hatching developed lymphomas by 39 weeks of age . Neonatal treatment with cyclophosphamide or surgical bursectomy at 2, 4, 8, or 12 weeks of age significantly (P less than 0.01) reduced lymphoma development . In a further experiment, surgical bursectomy of REV-infected chickens followed by intravenous inoculation of the chickens with a single cell suspension of their own bursa cells at 2, 4, 9, or 13 weeks of age resulted in lymphoid tumors in chickens treated at 9 or 13 weeks but not in chickens treated at 2 or 4 weeks of age . Furthermore, this treatment did not shorten the incubation period for lymphoma development . These findings argue very strongly that transforming target cells are primarily in the bursa of Fabricius . The data also suggest that a minimum residency of 4 weeks in the bursa is required for infected bursa cells to become transformed . Therefore, lymphomagenesis induced by REV in chickens appears similar to that induced by the avian leukosis virus group. Gen Comp Endocrinol, 1983 Jan, 49(1), 81 - 9 Preparation of enriched populations of corticotrophs from goldfish rostral pars distalis; Portanova R et al.; A mammalian isolated adrenal cell system was validated as a bioassay for goldfish ACTH; the log dose-response curve for the goldfish hormone is parallel to that for synthetic mammalian ACTH1-24, and the two ACTHs induce the same maximum rate of corticosterone production . Using this assay, it was observed that (1) there is a marked and consistent biphasic change in pituitary ACTH content as related to the length of time the fish are held in laboratory aquaria, and (2) the absolute and relative (to tissue wt) ACTH content of the rostral pars distalis is considerably greater than that of the proximal portion of the gland . Using a trypsin technique, isolated pituitary cells were prepared from both (rostral and proximal) portions of the gland; bioassay data indicate that cell suspensions prepared from the rostral pars distalis are enriched with respect to corticotrophs . The implications of these findings with regard to formulating an advantageous in vitro system for studying ACTH secretion are discussed. Am J Physiol, 1983 Jan, 244(1), H109 - 14 Maximum fluid concentrations of materials released from platelets at a surface; Adams GA et al.; We examine the estimation of local concentrations of materials that are released from the dense and alpha-granules of platelets during accumulation of platelets upon collagen-coated glass . Platelet/red blood cell suspensions were perfused through a 1.3-mm-ID tube . Empirical data were used in a calculation procedure, based on diffusion and convection, designed to yield an upper bound on the interfacial fluid concentration (IFC) for each substance considered . The necessary empirical data are the rate