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Biomedical subjects

K Koike

Publications and source records attributed to K Koike.

At least 541 records · Page 30Linked to original sources

Indirect estimation of filtration variables in rat lungs calculated by protein concentration or osmotic pressure method.

We reported a new way for estimating filtration variables: K(filtration coefficient), Ppmv (perimicrovascular pressure) and sigma (protein reflection coefficient), from 3 different measurements of weight gain at two protein concentrations of perfusate (Cmv) and at two vascular pressures (Pvasc). We used the Starling equation for calculating those variables using two different formulas which expressed that all protein moves by convection. In this report, we compared those two formulas: 1) 1--sigma = pi pmv/pi mv, which is already reported (Tanita et al. 1990), and 2) 1--sigma = Cpmv/Cmv. We measured filtration rate (Q) by a gravimetric method in isolated rat lung lobes in zone 1 conditions (alveolar pressure = 20 cmH2O) at two vascular pressures, Pvasc = 15 or 8 cmH2O and perfused the lobes with plasma containing a low or a high concentration of protein. By extrapolating the log of the rate of weight gain to t = 0, we obtain the initial filtration rate. Cmv was measured and pi mv was estimated by Yamada's equation (Yamada et al. 1985). The reflection coefficient calculated in 1--sigma = pi pmv/pi mv method is computed 10% higher than that in 1--sigma = Cpmv/Cmv method. However, the filtration coefficient or the perimicrovascular pressure calculated in either method was identical. We conclude that filtration variables can be estimated easily by pi method and those variables are comparable to those estimated by C method which are theoretically more acculate but more complicated in calculation.

Animals↗

Novel separation and amino acid sequences of alpha and beta subunits of pig heart pyruvate dehydrogenase.

Pyruvate dehydrogenase was separated from pig heart pyruvate dehydrogenase complex by gel-permeation chromatography on a TSK G4000SWG column in the presence of 4 M urea, followed by chromatography on a calcium phosphate gel-cellulose column. The pyruvate dehydrogenase was further separated into two nonidentical subunits, alpha and beta, by high-performance liquid chromatography on a Synchropak CM-300 column in the presence of 8 M urea. The complete amino acid sequences of two subunits of pyruvate dehydrogenase were determined. The peptide fragments of S-carboxymethylated subunits were generated by treatment with endoproteinase Lys-C, endoproteinase Asp-N, trypsin, and cyanogen bromide. The subunits alpha and beta contain 361 amino acid residues (Mr 40,294) and 329 residues (Mr 35,787), respectively. The amino acid sequences of subunits alpha and beta in the pig were, respectively, 98 and 96% identical to those in humans. Hydropathy analysis and prediction of the secondary structure of two subunits suggest that the subunit alpha contains the thiamin pyrophosphate-binding domain and that the subunit beta contains segments with a high hydrophobicity.

Amino Acid Sequence↗

Epitope analysis of cluster 1 and NK cell-related monoclonal antibodies.

By flow cytometric assays, we tested the antibodies of the Second International Workshop on Small Cell Lung Cancer Antigens against 20 normal peripheral leukocytes, four small cell lung cancer (SCLC) cell lines (one classic type, and three variant type) and one gastric cancer line (KATO 3). Thirteen antibodies (Code # 4, 12, 21, 31, 34, 41, 48, 58, 60, 61, 74, 77, 82) among 98 registered antibodies showed a very similar pattern to antibody NE150, which was previously characterised as SCLC cluster 1. Since NE150 showed a positive reaction to the natural killer (NK) cell population, the serological specificity was compared with NK cell-associated antibodies, NKH1 (CD56), Leu7 (CD57) and Leu11 (CD16). Only NKH1 antibody showed a similar pattern to NE150, when tested against various target cells including SCLC lines and peripheral leukocytes, suggesting that NKH1 is a cluster 1 antibody, although it was already classified as CD56 of hematopoietic cells. By sequential immunoprecipitation, the antigen detected by NE150 antibody was depleted by preincubation with NKH1 antibody, but the reactivity of NE150 was not inhibited by NKH1 antibody, suggesting that NE150 and NKH1 detect different epitopes on the same antigen molecule. Epitope analysis was also conducted with 13 antibodies of cluster 1. Ten were found to detect the same epitope as NE150. The other three did not inhibit the binding of NE150 or NKH1, suggesting that there are at least three epitopes. Since the cluster 1 antibodies were demonstrated to detect NCAM, the present results suggest the presence of at least three epitopes on this molecule.

Antibodies, Monoclonal↗

Stereoselective disposition and metabolism of disopyramide in pediatric patients.

Pharmacokinetics of disopyramide (DP) enantiomers was studied in six pediatric patients, 5 to 12 years old, with arrhythmias after i.v. and p.o. administrations of racemic DP. The enantiomers of DP and its active metabolite, mono-N-dealkyldisopyramide, in plasma and urine were determined using a chiral, high-performance liquid chromatography. Plasma protein binding of DP was measured by ultrafiltration. Because the protein binding of DP was not only concentration-dependent but also stereoselective (i.e., S-DP binds to protein more extensively than R-DP), unbound pharmacokinetic parameters were used for evaluating the kinetic behaviors of DP enantiomers. The pediatric age patients had the mean (+/- S.D.) systemic clearance of 15.0 +/- 3.8 and 12.7 +/- 3.9 ml/min/kg for unbound S- and R-DP, respectively, which were not only stereoselectively different (P less than .05) but also at least about twice greater than the reported normal adult values. The mean postinfusion elimination half-life values for unbound S- and R-DP (2.7 +/- 0.5 and 2.8 +/- 0.4 hr, respectively) in pediatric patients were shorter than those reported from normal adults (approximately equal to 4 to 5 hr). The mean nonrenal (i.e., hepatic) clearance for unbound S- and R-DP (11.1 +/- 4.1 and 8.1 +/- 3.9 ml/min/kg, respectively) were also stereoselectively different (P less than .01) and accounted for approximately equal to 70% of the unbound systemic clearance of the respective enantiomers.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

Requirement of both interleukin 3 and interleukin 6 for the growth of primitive hemopoietic progenitors.

Using a serum-free culture system, we studied the interaction of interleukin 3 (IL-3) and interleukin 6 (IL-6) in the development of primitive hemopoietic progenitors. A time-course study showed that total colony formation supported by 200 U/ml of IL-3 alone failed to reach the level obtained by the combination of 40 ng/ml of IL-6 and IL-3 in culture containing bone marrow cells of 5-fluorouracil (5-FU) -treated mice. Extremely high concentrations (1,000 U/ml, 10,000 U/ml) of IL-3 also required the presence of IL-6 for the sufficient development of primitive progenitors. The depletion of phagocytic and T cells from crude bone marrow cells of 5-FU-treated mice did not influence the requirement for both factors. These results suggest the existence of primitive progenitors which require both IL-3 and IL-6 for development. The delayed addition of IL-6 to a culture initiated with IL-3 failed to restore total colony growth to the levels obtained by culture initiated with the two factors simultaneously. The results suggest that some primitive hemopoietic progenitors requiring both IL-3 and IL-6 for the substantial growth may be unable to survive in the presence of IL-3 alone.

Animals↗

[Evaluation of cardio-pulmonary function for lobectomy under the condition of selective pulmonary arterial occlusion test (SPAO)].

We performed selective pulmonary arterial occlusion test (SPAO) and unilateral pulmonary arterial occlusion test (UPAO) in 30 patients with lung cancer who would be undertaken right lower lobectomy or middle and lower lobectomy, and evaluated the preoperative cardio-pulmonary function. The lung hemodynamics during SPAO were different from those during UPAO. This indicates that SPAO evaluated reserve capacity of vascular bed in the right upper lobe which would be remained at the surgery. Moreover, the ratio of total pulmonary vascular resistance during SPAO to that of before SPAO was not differed in two groups, one was a group with and the other was a group without impaired reserve capacity of vascular bed in the contralateral lung. This suggests that reserve capacity of pulmonary vascular bed including right upper lobe would be well compensated even in the patients with highly impaired capacity in the contralateral lung. Based on these findings, we performed lung resections in 9 patients, who were judged contraindications for lung resection by the results of UPAO, and no patient suffered postoperative cardio-pulmonary complications. Total pulmonary vascular resistance immediately after the right middle and lower lobectomy were equal to those during SPAO. Thus we conclude that SPAO is very useful technique for evaluating cardiopulmonary function after right lower lobectomy or middle and lower lobectomy, and that it would be possible to extend the boundaries of safety for lung resection based on evaluation of cardio-pulmonary function by SPAO.

Aged↗

[Lung function after lobectomy in chronic pulmonary emphysema].

We compared the prediction of postoperative pulmonary function in two groups: chronic pulmonary emphysema (CPE) group (n = 30) and normal control group (n = 41). These patients had a lobectomy because of lung cancer. We measured pulmonary function test (FVC, EFV1, TLC, FRC, RV, DLco), and pulmonary perfusion scan before and after surgery. We found correlation between the predicted and measured postoperative values very close in control group. Whereas, in CPE group, these correlations were very low especially in FVC and FEV1. We also calculated the pulmonary function on the operated and the non-operated sides. The correlation were very high without FEV1 in control group and all the measured values did not correlate to the predicted values. On the non-operated side, the correlations were high in both control and CPE groups. From these results we can conclude that it is difficult to predict the postoperative pulmonary function in the case of chronic pulmonary emphysema.

Chronic Disease↗

[A successful surgical treatment of cor triatriatum with VSD, PDA and CoA].

A successful repair of cor triatriatum with VSD, PDA and CoA is reported. A two-month-old boy was admitted for evaluation of growth failure and cyanosis. Physical examination on admission revealed systolic murmurs at left sternal border. Chest X-ray showed increased pulmonary vascularities without cardiomegaly. Echocardiography showed abnormal wall in left atrium with VSD, PDA and CoA. An emergency operation consisting of patch closure of VSD, ligation of PDA and resection of the anomalous left atrial membrane were performed. At postoperative course, an episode of pulmonary hypertension crisis happened. But the patient tolerated this episode and survived.

Aortic Coarctation↗

[Successful surgical treatment of total anomalous pulmonary venous connection (supracardiac Ib type) showing an unusual shape of the pulmonary veins in an infant].

An experience of a 9-month-old infant with Darling's type Ib of total anomalous pulmonary venous connection is presented. In this case, the left pulmonary vein traveled horizontally behind the atrium, entered the right thoracic cavity and drained into the SVC together with the right lower, middle and upper pulmonary veins. The patient was treated with repair using Gersony-Malm's method and plasty of SVC because of the stenosis of the common pulmonary vein's entrance to the SVC. Her postoperative course was uneventful, and the result was satisfactory. To our knowledge, our case is the first successful correction not associated with other complex cardiac anomalies in the world.

Female↗

Induction of mixed erythroid-megakaryocyte colonies and bipotential blast cell colonies by recombinant human erythropoietin in serum-free culture.

The effects of recombinant human erythropoietin (rEp) on murine hematopoietic progenitors were studied using a serum-free culture. A high concentration of rEp stimulated the formation of mixed erythroid-megakaryocyte colonies (EM colonies) and blast cell colonies, as well as erythroid colonies, erythroid bursts, and megakaryocyte colonies from normal mouse bone marrow cells. Direct effects of rEp on EM colony, megakaryocyte colony, and erythroid burst formation were confirmed by depletion of accessory cells such as T cells, B cells, and macrophages from crude bone marrow cells, and inhibition of the colonies by the addition of rabbit anti-rEp antibody to the culture in a dose-dependent fashion. Replating experiments were performed to confirm the differentiating ability of blast cell colonies grown in the presence of rEp. Most of the blast cell colonies yielded not only secondary erythroid colonies but also megakaryocyte colonies in the presence of 2 IU/mL rEp. Some of the blast cell colonies produced secondary EM colonies in the presence of 16 IU/ml rEp of 2 IU/mL rEp plus interleukin-3, although no granulocyte-macrophage colonies were found in the secondary culture. These results suggest that Ep acts not only as a late-acting factor that is specific for erythroid progenitors, but also as a bipotential EM-stimulating factor for murine hematopoietic cells.

Animals↗

Antiproliferative effect of IFN-gamma on proliferation of mouse connective tissue-type mast cells.

Mouse rIFN-gamma suppressed clonal growth of tissue-type mast cells (CTMC) separated from mouse peritoneal cells (greater than or equal to 98% purity) in methylcellulose culture containing IL-3 + IL-4 in a dose-dependent fashion. The IFN-gamma-mediated suppression was also observed both in serum-free culture and in single-cell culture. In addition, mAb to mouse IFN-gamma neutralized the suppressive effect of IFN-gamma on CTMC proliferation supported by the combination of IL-3 + IL-4. These observations suggest a direct antiproliferative effect of IFN-gamma on CTMC. No suppression of CTMC proliferation was observed when CTMC were washed with alpha-medium after 24 h of preincubation with IL-3 + IFN-gamma and then cultured in methylcellulose medium containing IL-3 + IL-4. IFN-gamma had suppressive effects on CTMC after preincubation with IL-3 + IL-4. These preincubation studies suggest that IFN-gamma exerts a reversible inhibitory effect on CTMC which have entered into a proliferative state by IL-3 + IL-4, and has neither cytotoxic nor irreversible suppressive effects on resting CTMC in cultures containing IL-3 alone. CTMC proliferation after stimulation with the cross-linking of cell-bound IgE by specific Ag in the presence of IL-3 was also suppressed by IFN-gamma. By contrast, proliferation of CTMC induced by the combination of 12-O-tetradecanoyl phorbol-13-acetate + IL-3 was not affected by the addition of IFN-gamma to the culture. Based on these observations, we suggest that IFN-gamma antagonizes the colony inducing effect of IL-4 and IgE-Ag stimulation which act synergistically with IL-3 on CTMC.

Animals↗

Characterization and nucleotide sequence of the gene encoding the human pyruvate dehydrogenase alpha-subunit.

Genomic clones encompassing the entire gene (PDH alpha) encoding the human pyruvate dehydrogenase alpha-subunit (PDH alpha) have been isolated by screening a leukocyte genomic library in the cloning vector, lambda EMBL4. The PDH alpha gene spans 17082 bp and is composed of eleven exons and ten introns. All intron/exon splice junctions follow the GT/AG rule. A total of seven Alu repeats were found in five introns. The entire nucleotide (nt) sequence of the PDH alpha gene has been determined and typical consensus promoter sequences in the 5'-flanking region were found. The results of primer extension analysis imply that the PDH alpha gene transcription start point (tsp) is a thymine residue 124 bp upstream from the ATG start codon in exon 1. The structural organization and the tsp were compared with the recent report [Maragos et al., J. Biol. Chem. 264 (1989) 12294-12298]. Analysis of the PDH alpha gene resolves existing discrepancies among four published sequences of PDH alpha cDNAs. A 93-bp sequence that was missing in our sequence of cultured foreskin fibroblast PDH alpha cDNA [Koike et al., Proc. Natl. Acad. Sci. USA 85 (1988) 41-45] was identified in the gene as exon 6.

Amino Acid Sequence↗

Alpha 2-adrenoceptor mechanisms in guinea-pig trachea.

In the presence of propranolol tracheal strips from guinea-pigs were markedly contracted by norepinephrine and clonidine but only slightly by phenylephrine. The contractile responses to clonidine and norepinephrine were inhibited by yohimbine but not by prazosin. The specific binding of [3H]p-aminoclonidine to the microsomal fractions from guinea-pig tracheal muscle was much greater than that of [125I]BE2254. These results indicate that alpha 2-adrenoceptors are the predominant subtype of alpha-adrenoceptor in the guinea-pig trachea. The response to norepinephrine was abolished by cyclooxygenase inhibitors, suggesting the release of excitatory prostaglandins by norepinephrine. These results raise the possibility that norepinephrine interacts with alpha 2-adrenoceptors and releases prostaglandins to contract tracheal muscle.

Adrenergic alpha-Antagonists↗

Interleukin-6 enhances murine megakaryocytopoiesis in serum-free culture.

We investigated the effect of interleukin-6 (IL-6) on murine megakaryocytopoiesis in a serum-free culture system. The addition of IL-6 to a culture containing interleukin-3 (IL-3) resulted in a significant increase in the number of megakaryocyte colonies by bone marrow cells of normal mice. The megakaryocytic progenitors that survive exposure to 5-fluorouracil (5-FU) exhibited a more significant response to IL-6 and IL-3. Polyclonal anti-IL-6 antibody neutralized the stimulatory effect of IL-6 on megakaryocyte colony growth supported by IL-3. Delayed addition experiments and replating experiments of blast cell colonies showed that megakaryocytic progenitors are supported by IL-3 in the early stage of the development but require IL-6 for their subsequent proliferation and differentiation. In addition, IL-6 increased the size of megakaryocytes in granulocyte-macrophage-megakaryocyte colonies. The combination of granulocyte colony-stimulating factor or granulocyte-macrophage colony stimulating factor with IL-3 resulted in an increase in the granulocyte-macrophage colony growth of bone marrow cells of 5-FU-treated mice or normal mice, respectively, but had little effect on the enhancement of pure and mixed megakaryocyte colony growth. These results suggest that IL-6 plays an important role in murine megakaryocytopoiesis.

Animals↗

Three-dimensional structure of the oligosaccharide terminus of globotriaosylceramide and isoglobotriaosylceramide in solution. A rotating-frame NOE study using hydroxyl groups as long-range sensors in conformational analysis by 1H-NMR spectroscopy.

Spatial structures of the oligosaccharide parts of globotriaosylceramide, Gal(alpha 1-4)Gal(beta 1-4)Glc(beta 1-1)Cer (Cer = ceramide) and isoglobotriaosylceramide, Gal(alpha 1-3)Gal(beta 1-4)Glc(beta 1-1)Cer were investigated in (C2H3)2SO solution by means of laboratory and rotating frame NOE, hydroxyl protons being used as long-range sensors defining the distance constraints. Both oligosaccharides were found to exist in more than one conformation interconverting rapidly on the NMR time scale. The conformation of the Gal(alpha 1-4)Gal(beta 1-4)Glc beta trisaccharide dissolved in 2H2O appeared to be the same as that of the corresponding part of the glycosphingolipid in (C2H3)2SO solution.

Carbohydrate Conformation↗

In vivo effects of recombinant human interleukin-6 in primates: stimulated production of platelets.

In cynomolgus monkeys, twice daily subcutaneous injections of recombinant human interleukin-6 (rhIL-6) at doses of 5 to 80 micrograms/kg/d for 14 consecutive days caused dose-dependent increases in platelet count, usually continuing for more than 1 week after cessation of the injections. The count reached a level approximately twofold or more above the preinjection level even at 5 micrograms/kg/d, and at doses of more than 20 micrograms/kg/d, the increase became biphasic with a higher second peak 3 days after cessation of the injections. Morphologic analysis of the bone marrow after the 7 day-injections with 80 micrograms/kg/d revealed a marked increment in size of megakaryocytes compared with control, indicating the promotion of megakaryocyte maturation. Other changes attributable to the rhIL-6 treatment include dose-dependent loss of body weight, anemia, neutrophilia and monocytosis, elevation of serum C-reactive protein and alpha-1 acid glycoprotein levels, and decrease of serum albumin; all of which returned to normal within 1 week after cessation of the injections and were tolerable at doses of less than 10 micrograms/kg/d. These findings suggest that rhIL-6 may be an effective strategy for the treatment of thrombocytopenia.

Animals↗

Effects of interleukin-3 and interleukin-4 on the development of "connective tissue-type" mast cells: interleukin-3 supports their survival and interleukin-4 triggers and supports their proliferation synergistically with interleukin-3.

We examined the effects of interleukin-3 (IL-3) and interleukin-4 (IL-4) on connective tissue-type mast cells (CTMC) purified from murine peritoneal cells. Although both factors failed to induce extensive proliferation of CTMC, they stimulated CTMC proliferation synergistically in a dose-dependent manner. Pretreatment of CTMC with IL-3 and/or IL-4 indicated that the sustained presence of both factors was required for the development of type 1 mast cell colonies. The delayed addition of IL-3 to cultures of purified CTMC with IL-4 induced no colony formation, while the delayed addition of IL-4 to cultures with IL-3, even on day 28 of culture, induced type 1 colony formation. In replating type 1 colonies induced by IL-3 and IL-4 to secondary cultures with IL-3 alone, few secondary colonies developed. However, the delayed addition of IL-4 to the secondary culture induced many type 1 colonies. The purified CTMC cultured with IL-3 retained the morphological and cytochemical characteristics of CTMC, as well as proliferative ability. These observations indicate that IL-3 supports the survival of CTMC in methylcellulose culture and that IL-4 triggers and supports CTMC proliferation synergistically with IL-3. The serum-free culture of purified CTMC and the culture of single CTMC demonstrated that the synergistic effect of IL-3 and IL-4 on colony growth and the surviving effect of IL-3 on CTMC require no influence from accessory cells or other humoral factors.

Animals↗