Biomedical subjects

H D Kim

Publications and source records attributed to H D Kim.

At least 127 records · Page 7Linked to original sources

PubMed1985

Phagocytosis, chemiluminescence, and cell volume of alveolar macrophages from neonatal and adult pigs.

Broncho-alveolar cells lavaged from the lungs of 1- and 7-day-old piglets and adult pigs were examined to determine their alveolar macrophage content, cell size, and ability to phagocytyze emulsified oil droplets and to chemiluminesce in response to opsonized zymosan particles. Alveolar macrophages were identified by specific cytochemical stains and differential cell counts as being 95%, 97%, and 90% of the cell populations, respectively. The cell volume of macrophages from 1-day-old pigs was 383 +/- 40 microns3; while the cell volumes from 7 day and adult pigs were 1,660 +/- 265 and 1,411 +/- 310 microns3. Alveolar macrophage from 1-day-old piglets possessed little ability to engulf oil droplets; however, macrophages from 7-day-old piglets phagocytized these opsonized droplets at a rate equivalent to alveolar macrophages obtained from adult pigs. The phagocytosis of oil droplets by both 7-day and adult alveolar macrophages manifested similar characteristics. Both rates can be described by saturation kinetics, and while temperatures from 37 degrees to 30 degrees C had little effect, the rate declined rapidly between 30 degrees and 16 degrees C. Alveolar macrophages from 1-day-old piglets displayed a lower magnitude of chemiluminescence than cells from 7-day-old and adult pigs and did not always respond to zymosan exposure. On the other hand, 7-day-old and adult pig alveolar macrophages were quite similar in their ability to chemiluminesce. Increasing extracellular glucose from 1 to 20 mM induced a concomitant increase in chemiluminescence. The findings suggest that functionally competent alveolar macrophages emerge in the pig lung approximately 1 week after birth.

Aging↗

PubMed1984

NMR study of in vivo RIF-1 tumors. Analysis of perchloric acid extracts and identification of 1H, 31P and 13C resonances.

Perchloric acid extracts of radiation-induced fibrosarcoma (RIF-1) tumors grown in mice have been analyzed by multinuclear NMR spectroscopy and by various chromatographic methods. This analysis has permitted the unambiguous assignment of the 31P resonances observed in vivo to specific phosphorus-containing metabolites. The region of the in vivo spectra generally assigned to sugar phosphates has been found in RIF-1 tumors to contain primarily phosphorylethanolamine and phosphorylcholine rather than glycolytic intermediates. Phosphocreatine was observed in extracts of these tumor cells grown in culture as well as in the in vivo spectra, indicating that at least some of the phosphocreatine observed in vivo arises from the tumor itself and not from normal tissues. In the 31P-NMR spectra of the perchloric acid extract, resonances originating from purine and pyrimidine nucleoside di- and triphosphate were resolved. HPLC analyses of the nucleotide pool indicate that adenine derivatives were the most abundant components, but other nucleotides were present in significant amounts. The 1H and 13C resonance assignments of the majority of metabolites present in RIF-1 extracts have also been made. Of particular importance is the ability to observe lactate, the levels of which may provide a noninvasive measure of glycolysis in these cells in both the in vitro states. In addition, the aminosulfonic acid, taurine, was found in high levels in the tumor extracts.

Animals↗

PubMed1984

Distribution of insulin receptors in human erythrocyte membranes. Insulin binding to sealed right-side-out and inside-out human erythrocyte vesicles.

Analyses of insulin binding to human erythrocytes and to resealed right-side-out and inside-out erythrocyte membrane vesicles have revealed that high affinity insulin binding receptors are present on both sides of the erythrocyte membranes. Insulin binding to human erythrocytes was examined with the use of a binding assay designed to minimize the potential errors arising from the low binding capacity of this cell type and from non-specific binding in the assay. Scatchard analysis of equilibrium binding to the cells revealed a class of high affinity sites with a dissociation constant (Kd) of (1.5 +/- 0.5) X 10(-8) M and a maximum binding capacity of 50 +/- 5 sites per cell. Interestingly, both resealed right-side-out and inside-out membrane vesicles exhibited nearly identical specific sites for insulin binding. At the high affinity binding sites, for both right-side-out and inside-out vesicles, the dissociation constant (Kd) was (1.5 +/- 0.5) X 10(-8) M, and the maximum binding capacity was 17 +/- 3 sites per cell equivalent. These findings suggest that insulin receptors are present on both sides of the plasma membrane and are consistent with the participation of the erythrocyte insulin receptors in an endocytic/recycling pathway which mediates receptor-ligand internalization/externalization.

Binding Sites↗

PubMed1984

Active cation transport and Na+K+Mg ATPase of the monotreme erythrocytes.

The erythrocytes of the echidna (Tachyglossus aculeatus) and platypus (Ornithorhynchus anatinus), which are practically devoid of intracellular ATP content (1), were examined for active Rb86 influx and for the presence of Na+K+Mg ATPase. We found that intact erythrocytes of both species possess the ability to actively transport cations. Ouabain sensitive Rb86 influx in the echidna was approximately 0.17 mumoles/ml cells x hr, whereas the platypus exhibited a higher value of 0.43 mumoles/ml cells x hr. Surprisingly, ouabain sensitive Na+K+Mg ATPase activity of isolated membranes was high amounting to some 15 to 25 fold higher than the human erythrocyte counterpart determined under identical conditions. These findings suggest that a trace amount of ATP is sufficient to maintain active cation transport across the monotreme cell membranes.

Animals↗

PubMed1984

Metabolic properties of low ATP erythrocytes of the monotremes.

The erythrocytes of the monotremes, having a trace amount of ATP, can metabolize glucose to lactate at a rate comparable to human and other mammalian erythrocytes. The echidna energy metabolism is unique in that adenosine can stimulate glycolytic carbon flow, resulting in a nearly 20-fold net synthesis of ATP.

Adenosine Triphosphate↗

PubMed1984

Pig reticulocytes. V. Development of Rb+ influx during in vitro maturation.

Influx of the K+ analogue Rb+ was measured through the ouabain-sensitive Na+/K+ pump and the ouabain-insensitive "leak" pathways in Cl- or NO3- in mature red cells from adult pigs and in reticulocytes naturally occurring in 7-day-old piglets. In reticulocytes, Rb+ influxes by the two pathways were of about equal magnitude in Cl- (13 and 10 mmoles/liter cells X hr) and at least 25-fold larger than in mature red cells (0.5 and 0.4 mmoles/liter cells X hr). In Na+ media, a portion of the ouabain-insensitive "leak" flux of Rb+ was Cl(-)-dependent (Rb+Cl- transport) as NO3- replacement reduced Rb+ influx by 90% in reticulocytes and by 40% in mature red cells. The sulfhydryl reagent N-ethylmaleimide (NEM) stimulated Rb+Cl- transport about twofold in reticulocytes and up to 13-fold in mature red cells. When reticulocytes matured to erythrocytes during in vitro incubation, about 90% of both ouabain-sensitive Rb+ pump and ouabain-insensitive Rb+Cl- influx were lost. In contrast, the NEM-stimulated Rb+Cl- transport changed much less throughout this period, suggesting an entity operationally but not necessarily structurally distinct from the basal Rb+Cl- transport. Although the experimental variability precluded a full assessment of significant changes in the small Na+/K+ (Rb+) pump and Rb+Cl- fluxes in mature pig red cells kept for the same time period in vitro, Rb+ flux changes in reticulocytes appear to be maturational in nature, reflecting parallel activity transitions of Na+/K+ pump and Cl(-)-dependent K+ fluxes in vivo.

Animals↗

PubMed1984

Developmental changes in insulin receptors of pig red blood cells.

Scatchard analysis of the insulin binding to pig reticulocytes, fetal red cells, and adult erythrocytes showed the maximum number of high-affinity binding sites per cell to be 274, 147, and 29, respectively. All three cell types displayed a practically identical dissociation constant of approximately 1.22 X 10(-8) M at the high-affinity region. A long-term in vitro incubation of the fetal red cells and reticulocytes under tissue culture conditions was accompanied by a significant loss of insulin-binding capacity without any appreciable alteration of the dissociation constant. The isolation and characterization of insulin-receptor complexes from these cell types were carried out to establish whether the difference in insulin-binding capacity was due to the difference in the amount of the same species or due to different species of insulin receptors. Membrane proteins were extracted with Triton X-102 and fractionated by DEAE-Sephacel ion-exchange column chromatography. Each peak sample was complexed with 125I-insulin, and the complexes were covalently crosslinked and then applied to a Sepharose CL-6B column. A 95,000-Da complex was obtained from adult pig erythrocyte membranes; 220,000- and and 95,000-Da complex was obtained from adult pig erythrocyte membranes; 220,000- and 95,000-Da complexes from pig reticulocyte membranes; and greater than 600,000-, 220,000-, and 95,000-Da complexes from pig fetal cell membranes. Upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis under a nonreducing condition, the 95,000-Da complex was dissociated into a 53,000-Da component; the greater than 600,000-Da complex into greater than 320,000-, 130,000-, and 53,000-Da components; and the 220,000-Da complex was dissociated into 220,000-, 130,000-, and 53,000-Da components. These findings strongly suggest that the decrease in insulin binding during the developmental changes of red blood cells is due to a disappearance of high-molecular-weight insulin receptors rather than a decrease in the amount of the smaller receptor molecules.

Aging↗

PubMed1984

Erythrocyte phosphate composition and osmotic fragility in the Australian lungfish, Neoceratodus fosteri, and osteoglossid, Scleropages schneichardti.

The packed cell volume (PCV), hemoglobin concentration (g/dl) and mean corpuscular volume (MCV) in the Australian lungfish, Neoceratodus fosteri, and in one of three Australian osteoglossids, Scleropages schneichardti, were 32.3 and 29.9; 10.5 and 10.0; and 407 and 176 micron 3 respectively. Total acid-soluble phosphates (TPi) from the red blood cells (RBC) of the lungfish and osteoglossid were 35.3 and 18.1 mumol/cm3 RBC respectively. Inorganic phosphate (Pi), adenosine triphosphate (ATP) and guanosine triphosphate (GTP) represented 16.4, 39.7 and 17.8% of the cell phosphates in the lungfish respectively. Inositol bisphosphate was not present in extracts of the red cells of N. fosteri, in contrast to the red cells of Lepidosiren paradoxa and Protopterus aethiopicus, in which it was first observed. In the osteoglossid, Pi and ATP represented 37.6 and 46.4% of the erythrocyte phosphate, respectively, with only traces of GTP present. ATP is the predominant organic phosphate in the red cells of both species. The osmotic fragility of erythrocytes of N. fosteri are quite resistant to hemolysis, with hemolysis beginning at 35-30 mM and a complete hemolysis occurring at 20 mM NaCl. The red cells of S. schneichardti begin to hemolyze at 95-90 mM with hemolysis continuing to completion at 60 mM NaCl.

Adenine Nucleotides↗

PubMed1984

Isolation and characterization of beta 1-adrenergic receptors from adult, rat cardiac myocytes.

The beta-receptors were isolated from rat cardiac myocytes and characterized. Isolated myocytes were prepared from adult rat hearts and characterized for viability. Membrane proteins were solubilized from myocytes with 1% Triton X-102. The solubilized membrane proteins were fractionated by DEAE-Sephacel ion exchange column chromatography. Two major protein peaks were obtained. The second protein peak sample was found to contain beta-receptors to which 125I-15-(4'-azido-3'-iodobenzyl)-carazolol (125I-ABC) was specifically bound. This sample was labeled covalently with 125I-ABC by UV irradiation. The radiolabeled sample was applied to a Sepharose CL-6B gel column. Two radiolabeled protein peaks, one with a molecular weight of approximately 570,000 and the other with a molecular weight of approximately 95,000 were found. When the 570,000-dalton complex was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions, it was dissociated into a component with a molecular weight of 66,000. The 95,000-dalton complex was dissociated into a 58,000-dalton component upon SDS-PAGE under reducing conditions. An excess amount of isoproterenol and propranolol decreased photolabeling of the beta-receptors with 125I-ABC by 60% and 40%, respectively.

Adrenergic beta-Antagonists↗

PubMed1984

Erythrocyte phosphates and hemoglobin function in monotremes and some marsupials.

Hematologic values, red blood cell (RBC) organic phosphate composition, hemoglobin function, and hemoglobin composition have been determined on blood from the monotremes, the duckbill platypus and the echidna, and three species of marsupials, the Tasmanian devil, the wallaby, and the brush-tail possum. Blood from the platypus had a RBC count of 8.63 X 10(6)/mm3, a mean corpuscular volume of 49.1 millemicron3, and a white blood cell count of 26.0 X 10(3)/mm3. The RBCs from the monotremes and the three marsupials exhibited hemoglobin polymorphism, each with three hemoglobin components. Addition of ATP, 2,3-bisphosphoglycerate (2,3-P2-glycerate), or inositol pentakisphosphate (inositol-P5) to phosphate-free hemoglobin from each species decreased hemoglobin oxygen affinity; the order of effect of these compounds was ATP less than 2,3-P2-glycerate less than inositol-P5. The RBCs of all species had concentrations of 2,3-P2-glycerate ranging from 6.02 mumol/ml RBCs in the wallaby to 10.39 mumol/ml RBCs in the possum. The RBCs from the three species of marsupials had concentrations of ATP ranging from 0.24 mumol/ml RBCs in the possum to 0.80 mumol/ml RBCs in the Tasmanian devil. The level of ATP in RBCs of the platypus and echidna were 0.06 and 0.03 mumol/ml RBCs, respectively.

Adenosine Triphosphate↗

PubMed1984

Comparison of 2,3-diphosphoglycerate metabolism between fetal and postnatal pig red cells.

A four-fold increase in red blood cell 2,3-diphosphoglycerate (DPG) levels occurs within 1-2 weeks after birth resulting in a decrease in oxygen affinity in the newborn pig. In this study, we found that although newborn pig red blood cells seem to be equally capable of net DPG synthesis as adult pig cells when challenged by a mixture of inosine, pyruvate and phosphate, the cells from newborns degrade DPG much faster than do cells from adults. As a result, DPG levels in the newborn's cells do not seem to increase in comparison to the adult's cells. Using a density centrifugation technique, it was found that the postnatal cells initially entering the circulation have a relatively low rather than high DPG content. However, DPG content quickly increases as they age. These findings suggest that the rapid rise of DPG seen in the growing piglet is brought about in part (a) by an elimination of the fetal cells with low DPG, and (b) by an emergence of postnatal cells having the capacity to augment their DPG content while in circulation.

2,3-Diphosphoglycerate↗

PubMed1983

Isolation and characterization of human erythrocyte insulin receptors.

The noncovalently associated 125I-insulin-receptor complex was isolated from human erythrocyte membranes after allowing 125I-insulin to interact with the membranes followed by extraction of the 125I-insulin-receptor complex with Triton X-102 or, alternatively, by complete solubilization of the membranes with sodium dodecyl sulfate (SDS), removal of SDS, and then treatment of the solubilized sample with 125I-insulin. Sepharose CL-6B column chromatography of the 125I-insulin-receptor complex obtained by both of the above procedures yielded a highly radioactive 140,000-Da complex which was dissociated into small peptides when subjected to SDS-polyacrylamide gel electrophoresis. In contrast, when the 125I-insulin-treated membrane sample was extracted with Triton X-102, purified by DEAE-Sephacel ion exchange chromatography, covalently cross-linked with disuccinimidyl suberate, and then subjected to SDS-polyacrylamide gel electrophoresis, a highly radioactive component with Mr = 53,000 was obtained. On the other hand, when the Triton X-102-solubilized membrane receptor sample was fractionated by DEAE-Sephacel ion exchange chromatography, complexed with 125I-insulin, covalently crosslinked, and then applied to a Sepharose CL-6B column, a 95,000-Da complex with high specific radioactivity was obtained. Upon SDS-polyacrylamide gel electrophoresis, the 95,000-Da complex was dissociated into a 53,000-Da component which appeared identical with that obtained from the receptor complex described above which was obtained by direct interaction of the membranes with 125I-insulin.

Chromatography, Gel↗

PubMed1982

Partial characterization of insulin receptors from rat myocytes.

Isolated myocytes were prepared from the adult rat heart and characterized for viability. The myocytes were exposed to 125I-insulin, and the 125I-insulin-receptor complex was extracted with 1% Triton X-102 and then applied to a DEAE-Sephacel column. When the chromatography were applied to a Sepharose CL-6B column, a 140,000-dalton complex with high specific radioactivity was found. Alternatively, when myocyte insulin receptors were first extracted with 1% Triton X-102 without prior exposure to 125I-insulin and then applied to a DEAE-Sephacel column, three peak protein fractions were obtained. They were treated separately with 125I-insulin and the 125I-insulin-protein complexes were covalently cross-linked with disuccinimidyl suberate. The cross-linked samples were applied to a Sepharose CL-6B column and the radioactive protein fractions were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The first and second peak samples from the ion exchange chromatography yielded complexes of low specific radioactivity, which appear to be formed by nonspecific random binding of 125I-insulin to the solubilized membrane proteins. In contrast, Sepharose CL-6B gel filtration of the cross-linked sample from the third peak fractions gave a major highly radioactive 125I-insulin-receptor complex with a molecular weight of 370,000 and a minor complex of low radioactivity with a molecular weight of 140,000. Upon sodium dodecyl sulfate-gel electrophoresis, the 370,000-dalton complex was dissociated to 130,000- and 82,000-dalton components and the 140,000-dalton complex was dissociated to a 47,000-dalton component.

Animals↗

PubMed1982

Pig reticulocytes. IV. In vitro maturation of naturally occurring reticulocytes with permeability loss to glucose.

Naturally occurring reticulocytes of week old piglets were used to characterize the maturation process under in vitro conditions. When the reticulocytes were suspended in tissue culture medium fortified with metabolic substrates, nearly all cells were viable after 24 hours incubation and usually more than 85% of the initial cell population survived after an 80 hour period. In cells maintained as long as a week in incubation, an adequate level of total adenine nucleotide with a large accumulation of IMP was found. In most cases, reticulocytes lose their reticular materials within two days and assume normal erythrocyte configuration. Concomitant with the morphological change, the cell volume decreases toward normal erythrocyte size, the extent of which can be accounted for by the intracellular loss of salt and accompanying water. As in the in vivo reticulocyte maturation process, reticulocytes undergoing in vitro maturation lose their membrane permeability to glucose. These findings suggest that the process of reticulocyte maturation occurring in cell culture approaches that which naturally occurs in vivo. Thus, these cells may be used to delineate the mechanism of the loss of membrane transport of glucose which normally occurs in the adult pig cells.

2,3-Diphosphoglycerate↗

PubMed1981

Adenosine triphosphate-deficient erythrocytes of the egg-laying mammal, echidna (tachyglossus aculeatus).

The erythrocytes of the short-beaked echidna (Tachyglossus aculeatus), an egg-laying mammal, were examined for the presence of phosphorylated compounds. The erythrocytes contained only 0.03 +/- 0.01 micromoles of adenosine 5'-triphosphate per milliliter of cells. This amount is two orders of magnitude less than that in human cells. Although the echidna erythrocytes had an abundance of 2,3-diphosphoglycerate and other glycolytic intermediates, no other energy-rich pyridine and purine compounds were detected.

Adenosine Triphosphate↗

PubMed1980

The development of non-Hodgkin's lymphoma following therapy for Hodgkin's disease.

Three patients developed non-Hodgkin's lymphoma (NHL) 3-6 years after treatment for Hodgkin's disease (HD). In no instance was there evidence of recurrence of HD following the initial chemotherapy or radiotherapy. None of these patients had received both radiation therapy and chemotherapy. The histologic classification of the developing of the developing NHL for the three patients was (1) diffuse, poorly differentiated lymphocytic, (2) nodular histocytic, and (3) nodular, poorly differentiated lymphocytic. In no instance was there any histologic similarity to the original HD. Perhaps most important with respect to histology was the easily demonstrable presence of Reed-Sternberg cells at the time of original diagnosis and their absence with onset of NHL. All patients responded well to conventional chemotherapy for NHL and are alive at 23+, 37+, and 65+ months after that secondary diagnosis. This report, when coupled with at least ten other such reported patients, suggests that NHL may be a relatively uncommon but significant complication of therapy for HD and must be distinguished for recurrence of HD.

Antineoplastic Agents↗

PubMed1980

Calmodulin. An activator of human erythrocyte (Ca2+ + Mg2+)ATPase phosphorylation.

The effect of purified calmodulin on the calcium-dependent phosphorylation of human erythrocyte membranes was studied. Under the conditions employed, only one major peak of phosphorylation was observed when solubilized membrane proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular weight of this phosphorylated protein band was estimated to be 130000 and in the presence of purified red blood cell calmodulin, the rate of phosphorylation of this band was increased. These data suggest that calmodulin activation of (Ca2+ + Mg2+)-ATPase could be a partial reflection of an increased rate of phosphorylation of the (Ca2+ + Mg2+)-ATPase of human erythrocyte membranes.

Ca(2+) Mg(2+)-ATPase↗

PubMed1980

Effects of calcium and soluble cytoplasmic activator protein (calmodulin) on various states of (Ca2+ + Mg2+)-ATPase activity in isolated membranes of human red cells.

(Ca2+ + Mg2+)-ATPase activity of red cells and their isolated membranes was investigated in the presence of various Ca2+ concentrations and cytoplasmic activator protein. Red cell ATPase activity was high at low Ca2+ concentrations, and low at moderate and high concentrations of Ca2+. In the case of isolated membranes, both low and moderate ca2+ concentrations produced higher (Ca2+ + Mg2+)-ATPase activity than high Ca2+ concentration. Membrane-free hemolysate containing soluble activator of (Ca2+ + Mg2+)-ATPase produced a significant increase in (Ca2+ + Mg2+)-ATPase activity only at low ca2+ concentration. Regardless of Ca2+ and activator concentrations, the enzyme activity in the membrane was lower than lysed red cells. The low level of (Ca2+ + Mg2+)-ATPase activity seen at high Ca2+ concentration can be augmented by lowering the Ca2+ concentration of EGTA in the assay medium. However, once the membrane was exposed to a high Ca2+ concentration, the activator could no longer exert it maximum stimulation at the low Ca2+ concentration brought about by addition of EGTA. This loss of activation was not attributable to the Ca2+-induced denaturation of activator protein but rather related to the alteration of (Ca2+ + Mg2+)-ATPase states in the membrane. On the basis of these data, it is suggested that only a small portion of (Ca2+ + Mg2+)-ATPase activity of isolated membranes can be stimulated by the soluble activator and that (ca2+ + Mg2+)ATPase most likely exists in various states depending upon ca2+ concentration and the presence of activator. The enzyme state exhibiting the high degree of stimulation by activator may undergo irreversible damage in the presence of high Ca2+ concentrations.

Ca(2+) Mg(2+)-ATPase↗