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Biomedical subjects

S Kondo

Publications and source records attributed to S Kondo.

At least 685 records · Page 38Linked to original sources

Effects of different lots of semen from the same bull on in vitro development of bovine oocytes fertilized in vitro.

The effectiveness of 8 different lots of semen from the same bull on the in vitro development of bovine oocytes fertilized in vitro was evaluated. Cleavage and development rates to the blastocyst stage were not significantly different among the 8 lots of semen. However, the cleavage and development rates varied no more than +/-11 and +/-6%, respectively, in overall rates. A maximum of 35.2 and 27.9% difference in cleavage and development rates to the blastocyst stage, respectively, was observed using a single straw from the same semen lot for insemination in 4 trials. This variation tended to be higher than that observed for the cleavage and development rates of oocytes after insemination with double straws from a single lot. These results indicate that the developmental capacity of embryos after insemination are affected by factors associated with a different semen lot from the same bull and with different straws from a single lot.

Journal Article↗

Antitumour activity of an immunoconjugate composed of anti-human astrocytoma monoclonal antibody and neocarzinostatin.

Neocarzinostatin (NCS) linked to the thiol group on the hinge region of the Fab' fragment of GA-17, a murine monoclonal antibody reacting with tyrosine-specific phosphorylated antigens, which are exclusively expressed on the cell surface of human astrocytomas, was evaluated for in vivo activity. GA-17-NCS immunoconjugates significantly suppressed the growth of human malignant glioma cell line U87-MG subcutaneous xenografts in nude mice until day 50 when administered intravenously into the tail vein. Disulphide- and thioether-linked GA-17-NCS were nearly equipotent immunoconjugates, but thioether-linked GA-17-NCS was more effective than disulphide-linked conjugates with 250 U/kg NCS content on day 50 (P < 0.05). Thioether-linked GA-17-NCS was significantly more effective on day 50 than free NCS with 500 U/kg or 250 U/kg NCS content (P < 0.05, P < 0.01, respectively). These results suggest that GA-17-NCS may prove useful in the treatment of human malignant gliomas.

Animals↗

IL-8 gene expression and production in human keratinocytes and their modulation by UVB.

Interleukin (IL)-8 is a member of the supergene family of proinflammatory and chemotactic cytokines recently termed chemokines. IL-8 has been implicated in the pathogenesis of inflammatory skin diseases such as psoriasis. In this study, IL-8 mRNA expression and protein production were determined in normal cultured human epidermal keratinocytes after ultraviolet-B (UVB) irradiation. Messenger RNA levels were determined by the reverse transcriptase-polymerase chain reaction (RT-PCR) method. Total RNA was extracted from cultured keratinocytes at various time points post-irradiation, reverse transcribed to cDNA, and amplified by PCR using a labeled specific primer for the target gene. Amplified products were sized by electrophoresis, visualized by autoradiography, and quantitated by densitometry. Autoradiographs were normalized relative to glyceraldehyde-3-phosphate-dehydrogenase (G3PDH) signals. Constitutive expression of IL-8 mRNA was seen in normal cultured keratinocytes. After 100 or 300 J/m2 UVB irradiation, a rapid increase in IL-8 mRNA level was observed within 1 h after irradiation. At 24 h after irradiation, the mRNA level was elevated 11-13 times compared with the control level. Production of IL-8 protein in culture supernatants was assayed by enzyme-linked immunosorbent assay (ELISA). Significant levels of IL-8 protein were observed at 24 h after irradiation. Cycloheximide treatment blocked this IL-8 protein induction. As IL-8 is known to be an inflammatory cell chemotactic factor, these results suggest a possible role for IL-8 in UVB-induced skin inflammation and diseases.

Cells, Cultured↗

Lipopolysaccharide isolated from a new O-antigenic form (O13) of Vibrio parahaemolyticus.

The chemical properties of a lipopolysaccharide (LPS) isolated from a new O-antigenic form (O13) of Vibrio parahaemolyticus were investigated. The LPS contained glucose, galactose, L-glycero-D-manno-heptose and glucosamine. 2-Keto-3-deoxy-octonate (KDO) was not detected in the LPS by the periodate-thiobarbituric acid test (Weissbach's reaction) under conventional hydrolysis conditions. Instead, phosphorylated KDO (X1 and X2) was found in its strong-acid hydrolysate. This sugar composition was identical to that of V. parahaemolyticus O3, O5 and O11 LPS, indicating that, based on the sugar composition, O13 LPS belongs to Chemotype III to which O3, O5 and O11 belong. In addition, structural study demonstrated the presence of KDO 4-phosphate in its inner-core region.

Carbohydrates↗

A chemotaxonomic study of Vibrio fluvialis based on the sugar composition of the polysaccharide portion of the lipopolysaccharides.

A chemotaxonomic study was carried out with a new serotyping scheme comprising 35 O-antigen groups of Vibrio fluvialis on the basis of the sugar composition of the polysaccharide portion of their lipopolysaccharide (LPS). A previously developed rapid method of preparing samples for compositional sugar analysis was employed. The 35 O-antigen groups were divided into 21 chemotypes. It is noted that a rarely occurring component sugar of gram-negative bacterial LPS, D-glycero-D-manno-heptose, and two kinds of uronic acids, i.e., galacturonic acid of a weakly bound type and glucuronic acid of a strongly bound type, were found in common in all the 21 chemotypes. A characteristic sugar component of gram-negative bacterial LPS, 2-keto-3-deoxyoctonate (KDO), was not detectable in any of the 21 chemotypes. Instead, three kinds of "KDO-like substances" were found, one in each of three chemotypes (III, XI and XVII). They were strongly positive in Weissbach's periodate-thiobarbituric acid test for KDO, but definitely not identical to it in high-voltage paper electrophoresis (HVPE); the substance present in chemotype XI was indicated by HVPE to be 3-deoxy-D-threo-hexulosonic acid which is a sugar constituent of Vibrio parahaemolyticus O7 and O12 LPS.

Carbohydrates↗

Chemical analysis of lipopolysaccharides of Shigella sonnei form II strains expressed by cloned form I antigen genes.

A compositional sugar analysis was carried out on lipopolysaccharide (LPS) from Shigella sonnei form II in which a plasmid with cloned form I antigen genes had been introduced. The recipient form II strains contained galactose, glucose, heptose, glucosamine, and 2-keto-3-deoxyoctonic acid (KDO) (2: 3: 1: 2: 2) in its LPS, while the transformant form I LPS contained, besides these sugars, N-acetyl-L-altrosaminouronic acid as an additional sugar constituent, which is known to be one of the antigenic determinants of form I antigen.

Cloning, Molecular↗

Granulocyte colony-stimulating factor (G-CSF)-induced mobilization of circulating haemopoietic stem cells.

We studied the utility of G-CSF for harvesting circulating haematopoietic stem cells in patients with leukaemia or lymphoma based on a comparative study in a single patient. Two successive cycles of leukapheresis following cytotoxic chemotherapy were performed in 22 patients as follows: the first cycle was performed with cytotoxic mobilization in all patients while the second cycle was randomized into two groups: cytotoxic (n = 10) and cytotoxic plus G-CSF (cytotoxic/G-CSF) (n = 12) mobilization. Repetitive cytotoxic mobilization did not alter the yields of mononuclear cells (MNC), myeloid (CFU-GM), and erythroid (BFU-E) progenitors. In contrast, cytotoxic/G-CSF mobilization produced significantly higher yields of MNC (2.6-fold), CFU-GM (5.5-fold), and BFU-E (3.9-fold) than did cytotoxic mobilization alone (P < 0.01). The ratio of CFU-GM to BFU-E was not affected by G-CSF. Furthermore, G-CSF led to an earlier peak of CFU-GM following chemotherapy. G-CSF is thus effective in expanding the pool of circulating haematopoietic progenitors.

Acute Disease↗

Abnormal erythrocyte band 4.1 protein in myelodysplastic syndrome with elliptocytosis.

A case of myelodysplastic syndrome with haemolytic anaemia and a marked elliptocytosis is reported. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of erythrocyte membrane proteins revealed that the patient's band 4.1 was decreased to about 50-70% of that of control and contained abnormal molecule migrating in a faster mobility than normal band 4.1, which was confirmed by immunoblotting. The actin/spectrin ratio of the patient's ghosts diminished to about 70% of that of control ghosts. Flowcytometric analysis showed that the glycophorin C content of the patient's erythrocytes was reduced but maintained the level of about 70% of that of normal, indicating that the glycophorin C-band 4.1 interaction might not be so seriously damaged as to cause elliptocytic shape change. We postulate that the abnormal band 4.1 produced from the abnormal erythroid clone may be the primary molecular defect and result in a dysregulation of spectrin-actin interaction to cause erythrocyte shape change and membrane instability.

Anemia, Refractory↗

International cooperation with Islamabad Children's Hospital, Pakistan: the JICA project.

The experience gained during 7 years of cooperation between the Japan International Cooperation Agency (JICA) and the Islamabad Children's Hospital (JICA-ICH project, July 1986-June 1993) is described. Islamabad Children's Hospital achieved the goals of the project and became a centre for excellence in health care, education and research for children, fulfilling the objectives of the project. This achievement was evaluated as one of the most successful projects in medical cooperation ever performed by JICA by a third party evaluation team. The problems arising and the lessons experienced through the process are discussed. The importance of the role which should be undertaken by pediatricians in international cooperation with developing countries is emphasized.

Child↗

Quantitative analysis of adrenergic alpha-1 and alpha-2 receptors in human prostatic urethral tissue.

We measured the adrenergic alpha-1 and alpha-2 receptors in 3 types of prostatic tissue (prostatic urethral mucosa, prostatic adenoma and prostatic capsule) in a group of patients with benign prostatic hypertrophy (BPH) and in another group without BPH, using radioligand binding techniques. In all tissues examined, more alpha-1 and alpha-2 receptors were found in the hypertrophy group than in the other group. The increase in density of these receptors in the hypertrophy group was most marked in the prostatic adenoma. The density of alpha-1 and alpha-2 receptors was almost the same in the adenoma in both groups. The prostatic capsule and urethra in both groups contained more alpha-1 than alpha-2 receptors. Both receptors were found more in the adenoma than in the other 2 tissues in both groups. These results suggest that alpha-1 and alpha-2 receptors both play an important part in the symptoms of benign prostatic hypertrophy.

Aged↗

A physical map of the sulfur-dependent archaebacterium Sulfolobus acidocaldarius 7 chromosome.

A chromosomal map of the sulfur-dependent thermoacidophilic archaebacterium Sulfolobus acidocaldarius 7 was constructed with four restriction enzymes: NotI, BssHII, RsrII, and EagI. The map indicated that the chromosome is a single circular DNA of 2,760 +/- 20 kb (mean +/- standard error of the mean). rRNA genes were also mapped. They were located at one site in the genome.

Blotting, Southern↗

Identification of a functional receptor for granulocyte colony-stimulating factor on platelets.

Since granulocyte colony-stimulating factor (G-CSF) is thought to be a granulocyte lineage-specific cytokine, G-CSF receptors on blood cells other than those of granulocyte or monocyte lineage have not been well investigated. We now report that G-CSF receptors are present on platelets. The expression of G-CSF receptors on platelets was demonstrated by flow cytometry and radioreceptor assay. The mean number of G-CSF-binding sites per cell was 41 and the binding affinity was high (Kd 300 pM), similar to the affinity observed on granulocytes. Cross-linking assay revealed that G-CSF receptors were present on a single subunit protein of approximately 150 kD on the platelets. To clarify whether or not G-CSF might produce some direct functional influence on platelet response, the effects on platelet aggregation were studied. Although G-CSF itself did not affect platelet aggregation in vitro, preincubation with G-CSF augmented a secondary aggregation of platelets induced by low concentrations of adenosine diphosphate (ADP). There was a dose-response relationship for this G-CSF activity at concentrations of up to 10 ng/ml. Furthermore, the augmented ADP-induced secondary aggregation of platelets on G-CSF receptors was completely abrogated in the presence of anti-G-CSF polyclonal antibodies. These results indicate that platelets possess functional G-CSF receptors.

Adenosine Diphosphate↗

Preparation and pharmacological evaluation of N3-substituted thymidine derivatives as central depressants.

Central depressant effects in mice of N3-substituted thymidines (Td) (1) were examined by intracerebroventricular (i.c.v.) injection. Nine derivatives including the methyl, ethyl, propyl, allyl, benzyl, xylyl and alpha-phenylethyl derivatives at the N3-position of 1 were synthesized and their pharmacological effects were evaluated by using hypnotic activity, pentobarbital-induced sleep prolongation and locomotor activity as indices for central depressant effects. At a dose of 2.0 mumol/mouse, the values of mean sleeping time induced by N3-benzylthymidine (6), N3-o-xylylthymidine (7), N3-m-xylylthymidine (8), N3-p-xylylthymidine (9) and N3-alpha-phenylethylthymidine (10) were 61, 30, 48, 45 and 23 min, respectively. These derivatives (2.0 mumol/mouse) prolonged pentobarbital-induced (40 mg/kg, i.p.) sleeping time. None of the alkyl (2-4) or allyl (5) derivatives exerted hypnotic activity, although the derivatives tested (2-10) significantly prolonged the pentobarbital-induced sleeping time. Compound 1 and its xylyl derivatives tested (0.25 mumol/mouse, i.c.v.) decreased locomotor activity. These results indicate that thymidine derivatives have central depressant activity, and the benzyl derivatives but not alkyl derivatives possess a hypnotic activity.

Animals↗

Effect of washing, antibiotics and trypsin treatment of bovine embryos on the removal of adhering K99+ Escherichia coli.

Bovine embryos with the intact zona pellucida were exposed in vitro to K99+ Escherichia coli (K99 E. coli). The recommended procedures for washing and treating embryos were then evaluated for their effectiveness in removing or killing the adherent bacteria. After 10-step washing, bacteria were recovered not only from the embryos exposed to E. coli suspensions but also from those treated with trypsin during washing. On the other hand, no bacteria were recovered from any embryos treated with antibiotics (gentamicin; 50 micrograms/ml) in culture medium before washing, indicating that the recommended washing procedures with appropriate antibiotics assure that zona pellucida-intact bovine embryos are free from E. coli.

Animals↗

Effect of trypsin treatment of in vitro fertilized bovine embryos on their subsequent survival and development.

The object of this study was to determine whether several washings with trypsin affected the survival and development of in vitro fertilized (IVF) bovine embryos. The embryos developed to blastocysts 7-8 days after insemination, were washed 12 times in washing medium (modified Dulbecco's phosphate-buffered saline (mPBS) containing 20% fetal bovine serum (FBS): 25 mM Hepes TCM199 with Earle's salts = 1:1), or in a series of three washes in the washing medium, two in mPBS containing 0.3% bovine serum albumin (BSA), two in 0.25% trypsin in Hank's solution (without Ca++ and Mg++) for a total time in the trypsin of 60 to 90 sec and five in the washing medium. After washing, the embryos were either cultured in vitro or cryopreserved. The fresh and frozen-thawed embryos were either cultured for 72 hr in vitro for evaluating development or transferred nonsurgically to recipient cows. Development of fresh and frozen-thawed embryos in vitro in control-washed and trypsin-washed embryos did not differ. Pregnancy rates did not differ (P > 0.05) among recipient cows receiving control-washed or trypsin-washed embryos, and transferring fresh or frozen-thawed embryos. These results indicate that the treatment of bovine IVF embryos with trypsin during washing did not have a positive effect on embryonic development.

Animals↗

Circadian variation of bronchial caliber and antigen-induced late asthmatic response.

To study whether circadian variation of bronchial caliber participates in causing late asthmatic response (LAR), house-dust inhalation was made at 10 AM and 6 PM on separate days in 6 house-dust-sensitive asthmatic children aged 8 to 13 years. Bronchial obstruction was assessed through measurements of FEV1 at 4-h intervals from 24 h before to 24 h after the inhalation. The LAR, which is a 15 percent or greater decrease in FEV1 from the value at the same hour of the previous day, occurred 4 h or later after the inhalation in all challenges. The mean (+/- SD) time to the occurrence of the lowest FEV1 (maximum LAR) following the morning inhalation was 14.7 +/- 2.1 h versus 10.0 +/- 2.2 h following the evening inhalation (p < 0.05). Regardless of the hour of inhalation, FEV1 after the inhalation was lowest or near-lowest at 2 AM in all. Therefore, the maximum LAR was indistinguishable from the trough of further amplified circadian variation in FEV1 following the inhalation. These findings suggest that the downward arm of circadian variation may partially participate in causing the LAR.

Adolescent↗

Spontaneous improvement in bronchial responsiveness and its limit during preadolescence and early adolescence in children with controlled asthma.

To study whether improvement in bronchial responsiveness contributes to outgrowing of asthma, PC20-histamine was measured longitudinally in nine nonsteroid-dependent asthmatic children (six boys, three girls), aged 8.1 to 9.8 years (mean, 9.2 years) at the beginning of the study. The measurement was discontinued when final inhaled histamine concentration in at least two consecutive measurements did not exceed the previous highest one. Two or more doubling concentration differences in inhaled histamine is regarded as significant in our center. Mean (SD) study period was 3.6 (0.8) years, interval of the measurements was 10.6 (2.3) months. Geometric mean of PC20-histamine at the beginning was 0.39 mg/ml. PC20-histamine improved significantly in seven of nine patients during the study period, though best values were less than 8 mg/ml in all. Mean (SD) age reaching the highest final concentration was 11.0 (0.8) years. These data suggest that the improvement in bronchial responsiveness may be one of mechanisms in the outgrowing of asthma around adolescence.

Adolescent↗