Biomedical subjects

H Kodama

Publications and source records attributed to H Kodama.

At least 397 records · Page 22Linked to original sources

PubMed1991

Congenital osteoclast deficiency in osteopetrotic (op/op) mice is cured by injections of macrophage colony-stimulating factor.

Osteopetrotic (op/op) mice have a severe deficiency of osteoclasts, monocytes, and peritoneal macrophages because of a defect in the production of functional macrophage colony-stimulating factor (M-CSF) resulting from a mutation within the M-CSF gene. In this study, we examined whether daily 5-microgram injections of purified recombinant human M-CSF (rhM-CSF) for 14 d would cure these deficiencies in the mutant mice. Monocytes in the peripheral blood of the op/op mice were significantly increased in number after subcutaneous injections of the factor two or three times a day. In contrast, osteopetrosis in the long bones of op/op mice was completely cured by only one injection of rhM-CSF per day. Bone trabeculae in the diaphyses were removed. Many osteoclasts were detected on the surface of bone trabeculae in the metaphyses. Although development of tooth germs of uninjected op/op mice was impaired, rhM-CSF injection restored the development of molar tooth germs and led to tooth eruption as a consequence of the recovery of bone-resorbing activity. These results demonstrate that M-CSF is one of the factors responsible for the differentiation of osteoclasts and monocyte/macrophages under physiological conditions.

Animals↗

PubMed1991

Response of newly established mouse myeloid leukemic cell lines to MC3T3-G2/PA6 preadipocytes and hematopoietic factors.

Some mouse myeloid leukemias induced by X-irradiation and serially transplanted into syngenic mice do not proliferate in vitro even in the presence of hematopoietic factors. To examine whether such leukemic cells can proliferate in response to stromal cells, we cocultured them with MC3T3-G2/PA6 (PA6) preadipocytes, cells that can support the growth of hematopoietic stem cells. All leukemias developed into in vitro cell lines, showing a dependence on contact with the PA6 cells. Two cell lines responded to none of the known hematopoietic factors including interleukin-3 (IL-3), IL-4, IL-5, IL-6, GM-CSF, G-CSF, M-CSF, and Epo. These results demonstrate that the mechanism of the action of PA6 cells is different from that of any of the known hematopoietic factors, and that, because these two leukemic cell lines retained the ability to grow in vivo, responsiveness to the known hematopoietic factors is not essential for the leukemic cell growth in vivo. Furthermore, all leukemic cell lines could respond also to the preadipocytes fixed with formalin, paraformaldehyde, or glutaraldehyde, suggesting that some molecule(s) associated with the surface of PA6 cells or with extracellular matrix secreted by the preadipocytes is responsible for the leukemic cell growth.

Adipose Tissue↗

PubMed1991

Identification of NAc-HCPC and NAc-beta-CEC, and qualitative analyses of sulphur amino acids in the urine of a patient with cystathioninuria using liquid chromatography/atmospheric pressure ionization mass spectrometry.

Standard sulphur amino acids and various cystathionine metabolites in the urine of a patient with cystathioninuria were analysed using liquid chromatography/mass spectrometry with an atmospheric pressure ionization interface system. Very intense quasi-molecular ions ([M + H]+) of synthetic cystathionine, N-monoacetylcystathionine, perhydro-1,4-thiazepine-3,5-dicarboxylic acid, S-(3-hydroxy-3-carboxy-n-propyl)cysteine, S-(2-carboxyethyl) cysteine, S-(2-hydroxy-2-carboxyethyl)homocysteine, S-(carboxymethyl)homocysteine, N-acetyl-S-(3-hydroxy-3-carboxy-n-propyl)cysteine and N-acetyl-S-(2-carboxyethyl)cysteine were observed by this method. Quasi-molecular ions ([M + H]+) of these sulphur amino acids were observed in the urine sample of the patient with cystathioninuria, and N-acetyl-HCPC and N-acetyl-beta-CEC as N-substituted sulphur amino acids were also identified in the urine of the same patient.

Acetylcysteine↗

PubMed1991

Genetic expression of Menkes disease in cultured astrocytes of the macular mouse.

The copper concentration was investigated in the cultured astrocytes from macular mice, an animal model of Menkes disease. An excessive amount of copper was accumulated in the astrocytes as copper-metallothionein. These results show that the underlying genetic defect of the macular mouse is expressed in the astrocytes. A similar situation may exist in Menkes disease and cause a failure of copper transport to neurones.

Animals↗

PubMed1991

High-performance liquid chromatographic determination of pyrophosphate in the presence of a 20,000-fold excess of orthophosphate.

An HPLC method was based on anion-exchange separation of pyrophosphate (diphosphate) and orthophosphate and postcolumn spectrophotometric detection at 140 degrees C with a molybdenum(V)-molybdenum(VI) reagent. The reagent was easy to prepare, stable for at least 6 months at room temperature, and ready for the determination of pyrophosphate and orthophosphate by the so-called heteropoly blue method without use of any reducing agent. A photodiode-array detector for HPLC indicated the spectral characteristics of the heteropoply blue complex that was detectable at 330-800 nm. The HPLC method had a wide dynamic range from 3 x 10(-7) to 5 x 10(-4) M for both pyrophosphate and orthophosphate with a relative standard deviation of measurement of 10 approximately 2%. Pyrophosphate of 5 x 10(-7) and 5 x 10(-6) M, respectively, could be determined in the presence of a 20,000-fold excess of orthophosphate; 0.01 and 0.1 M.

Chromatography, High Pressure Liquid↗

PubMed1991

Primary and secondary depression in alcoholism--clinical features and family history.

One hundred thirty-six alcoholic inpatients were studied with regard to the association between alcoholism and depression. They fell into three groups: primary depression, secondary depression and non-depressive alcoholism. The main results obtained are as follows: (1) Depression was found in 46 patients (33.8%) in the present or past history; 13 were regarded as primary depression and 33 as secondary depression. (2) The clinical symptoms and the background of the primary group resembled those of endogenous depression. (3) The clinical features, including the duration of depressive episodes in the secondary depression group differed from those in the primary group. (4) No statistically significant differences were noted as to the rates of family-history of alcoholism and depression among the three groups. Clinical and biological differences between the primary and secondary groups were discussed on the basis of these results.

Adult↗

PubMed1991

Changes of copper level and cytochrome c oxidase activity in the macular mouse with age.

The macular mouse is an animal model of Menkes disease. The neurological degeneration is caused by decreased cuproenzymes activity, such as cytochrome c oxidase (CCO), associated with copper deficiency in the brain. We investigated the age-related changes in copper concentration and CCO activity in the brain of macular mice which were given a single injection of cupric on postnatal day 7. The copper concentration in the brain of macular mice was always about 40% of that of the age-matched controls. However, the copper concentration of both macular and control mice increased with age gradually. The CCO activity in the brain of macular mice was significantly lower than that of controls at the age of 8 days. However the activity in macular mice increased with growth and reached a level equal to the controls at 180 days. These results suggest that the improvement of CCO activity in the brain of macular mice is due to the brain copper concentration which increased with age. Therefore, parenteral administration of copper is recommended especially during infancy in patients with Menkes disease.

Aging↗

PubMed1991

Isolation of Genes that Are Preferentially Expressed at the G(1)/S Boundary during the Cell Cycle in Synchronized Cultures of Catharanthus roseus Cells.

A cDNA library was screened for genes that may be involved in the progression of the cell cycle of cells of higher plants. The Catharanthus roseus L. (G) Don. cells were synchronized by the double phosphate starvation method, and a lambdagt11 cDNA library was prepared using poly(A)(+) RNA from cells in the S phase of the cell cycle. Two independent sequences, cyc02 and cyc07, were identified by differential screening. The levels of cyc02 and cyc07 mRNAs increased dramatically, but transiently, at the G(1)/S boundary of the cell cycle. High levels of cyc02 mRNA, but not of cyc07 mRNA, were also present in cells arrested at the G(1) phase by phosphate starvation. In an asynchronous batch culture, cyc02 and cyc07 mRNAs accumulated transiently at different stages of the growth cycle, cyc02 mRNA early in the stationary phase, and cyc07 mRNA in the midlogarithmic phase. When the proliferation of cells was arrested by nutrient starvation, i.e. by sucrose or nitrogen starvation, the relative amounts of the cyc02 and cyc07 mRNAs decreased. These results indicate that cyc02 and cyc07 contain nucleotide sequences from growth-related genes. The analysis of nucleotide sequence of cyc02 shows that the predicted product of this gene is basic and is composed of 101 amino acids. No significant homology to other known proteins was detected.

Journal Article↗

PubMed1991

Polyamines and the Cell Cycle of Catharanthus roseus Cells in Culture.

Investigation was made on the effect of partial depletion of polyamines (PAs), induced by treatment with inhibitors of the biosynthesis of PAs, on the distribution of cells at each phase of the cell cycle in Catharanthus roseus (L.) G. Don. cells in suspension cultures, using flow cytometry. More cells treated with inhibitors of arginine decarboxylase (ADC) and ornithine decarboxylase (ODC) were accumulated in the G(1) phase than those in the control, while the treatment with an inhibitor of spermidine (SPD) synthase showed no effect on the distribution of cells. The endogenous levels of the PAs, putrescine (PUT), SPD, and spermine (SPM), were determined during the cell cycle in synchronous cultures of C. roseus. Two peaks of endogenous level of PAs, in particular, of PUT and SPD, were observed during the cell cycle. Levels of PAs increased markedly prior to synthesis of DNA in the S phase and prior to cytokinesis. Activities of ADC and ODC were also assayed during the cell cycle. Activities of ADC was much higher than that of ODC throughout the cell cycle, but both activities of ODC and ADC changed in concert with changes in levels of PAs. Therefore, it is suggested that these enzymes may regulate PA levels during the cell cycle. These results indicate that inhibitors of PUT biosynthesis caused the suppression of cell proliferation by prevention of the progression of the cell cycle, probably from the G(1) to the S phase, and PUT may play more important roles in the progression of the cell cycle than other PAs.

Journal Article↗

PubMed1991

Identification of a novel S-phase-specific gene during the cell cycle in synchronous cultures of Catharanthus roseus cells.

The cell-cycle specific cDNAs were isolated from a cDNA library prepared from cells in the S phase in the synchronous cultures of Catharanthus roseus. One of the isolated genes, which we refer to as cyc07, was analyzed in detail. The full-length cDNA of cyc07 contains an open reading frame of 735 nucleotides, encoding a protein of 245 amino acids with a molecular weight of 28,356 Da. The protein predicted from the nucleotide sequence is highly basic, as are mammalian histones. cyc07 mRNA was detected specifically in cells at the S phase in synchronous cultures. The induction and accumulation of mRNA in the S phase were suppressed when DNA synthesis was inhibited by aphidicolin. In the intact plant, cyc07 mRNA was found preferentially in root tips that contained meristematic tissue. A databank search revealed that a sequence homologous to the nucleotide sequence of cyc07 cDNA is present in the downstream region of the SIR3 gene in the yeast genome. The amino acid sequence predicted from the corresponding region of the yeast genome exhibited significant homology with that of cyc07 protein. These similarities between cyc07 and the corresponding region in yeast suggest that the homologous sequence in yeast is a novel gene that is functionally homologous to cyc07. Our results presented here suggest the possibility that cyc07 may play a role in the proliferation of higher plant cells, in particular in the entry into or progression of the S phase of the cell cycle.

Amino Acid Sequence↗

PubMed1991

[Surveys on the contamination of marine fish with non-O1 Vibrio cholerae and Vibrio mimicus and food poisoning cases by these organisms].

The present paper describes the relationship between the contamination with non-O1 Vibrio cholerae and Vibrio mimicus of marine fish, with special reference to the seasonal variation and the concentration of contamination, and the actual cases of domestic food poisoning by these organisms. A 10 year survey revealed that non-O1 Vibrio cholerae (non-O1 V. cholerae) strains were frequently isolated from fish during the summer season with some variations from one year to another, and isolates from fish showed similar biological properties to those of isolates from diarrhea cases of over-sea travellers. Experimentally enteropathogenic strains were included among these isolates. Vibrio mimicus (V. mimicus) strains were also isolated from fish, the frequency being not so high as in the case of non-O1 V. cholerae Strains of serovar O-41 which was most predominant among strains from diarrhea cases were also detected among the isolates from fish. The viable cell counts, however, were very small with regard to both non-O1 V. cholerae and V. mimicus From these observations, factors causing food poisoning by non-O1 V. cholerae or V. mimicus seemed to be essentially similar to those by Vibrio parahaemolyticus (V. parahaemolyticus); that is, the food poisoning by non-O1 V. cholerae or V. mimicus is apt to occur in the summer season and is caused by the consumption of raw fish, although the frequency might be significantly low in comparison to that of V. parahaemolyticus. The actual cases of the domestic food poisoning by non-O1 V. cholerae or V. mimicus were retrospectively surveyed by the literature.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

[Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae. I. Enteropathogenicity of clinical and environmental isolates].

Enteropathogenicity and plasmid DNA of clinical and environmental isolates of non-O1 V. cholerae were examined. Results were as follows: 1). The frequencies of enteropathogenic strains judged by the results from both ligated rabbit ileal loop (RIL) and suckling mouse tests were 36/38 (95%) for isolates from overseas travellers, 15/15 (100%) for isolates from food poisoning, 33/44 (75%) for isolates from fish and sea water, and 1/10 (10%) for isolates from river water. 2). Plasmid DNA was detected in eight of the 40 isolates examined, but the presence of plasmid did not correlate with enteropathogenicity. These results indicate that approximately three fourths of the strains isolated from fish and sea water are enteropathogenic, and that the genes controlling the enteropathogenicity of this organism probably exist in chromosomal DNA.

Animals↗

PubMed1991

[Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae. II. Lethality, adhesion, colonization and cytopathogenicity of enteropathogenic strains].

Lethality, adhesion, colonization, hemagglutinable activity, invasiveness and cytopathogenicity of non-O1 V. cholerae were compared between enteropathogenic and non-enteropathogenic strains. The following results were obtained. 1) Minimum lethal doses (MLD) of enteropathogenic strains were significantly lower than those of non-enteropathogenic strains. 2) There were no differences in adhesive and hemagglutinating activities between enteropathogenic and non-enteropathogenic strains. 3) A greater majority of enteropathogenic strains showed cytopathogenic effect on HEp 2 cells, but non-enteropathogenic strains did not. 4) Regardless of enteropathogenicity of viable cells, none of the 13 strains examined were found to be invasive to HEp 2 cells. These results suggest that adhesion and colonization do not draw a clear distinction between enteropathogenic and non-enteropathogenic strains, and that both lethal and cytopathogenic activities of these organisms are correlated with enteropathogenicity.

Animals↗

PubMed1991

[Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae. III. Production of enteroreactive toxins].

Cholera toxin gene and production of enteroreactive toxins were examined in 134 strains of non-O1 V. cholerae. Results obtained were summarized as follows. Frequencies of cholera-toxin-gene-positive strains were 2/58 (3.4%) from human sources and 2/76 (2.6%) from fish and environment. While, frequencies of production of hemolysin, fluid accumulating factor (FAF) related with protease, fluid accumulating factor in the suckling mouse, NAG-rTDH, NAG-ST and Vero toxin were 100, 72, 31, 2, 0 and 0%, respectively, for 58 strains from human sources, and 100, 57, 24, 0, 1.3 and 0%, respectively, for 76 strains from fish and environment. Among the 31 strains used for the injection of viable cells to the ligated rabbit ileal loop, detection frequencies of these enteroreactive toxins in the accumulated fluids were 100% for hemolysin, 3.2% for both FAF and NAG-rTDH and 0% for cholera toxin, Vero toxin or NAG-ST. Hemolysin and the fluid accumulating factor in the suckling mouse seemed to be identical in most strains. These results suggest that cholera toxin, NAG-ST, NAG-rTDH and Vero toxin may not be very important in the enteropathogenic mechanism of a great majority of non-O1 V. cholerae strains, whereas hemolysin may play an important role in the enteropathogenicity.

Animals↗

PubMed1991

[Studies on the enteropathogenic mechanism of non-O1 Vibrio cholerae. IV. Role of hemolysin].

The role of hemolysin in the enteropathogenic mechanism of non-O1 V. cholerae was experimentally investigated, in vitro and in vivo. Results are summarized as follows. 1). A greater majority of enteropathogenic strains produced hemolysin in Eagle MEM medium supplemented with 10% calf serum and in the rabbit ileal loop, while most non-enteropathogenic strains did not under the same conditions. 2). Non-enteropathogenic mutants derived from enteropathogenic parent strains produced much less hemolysin than that of parent strains. 3). A significant inhibition of the fluid accumulation in the ligated rabbit ileal loop test with viable cells was noted in rabbit immunized with purified hemolysin. These results indicate that hemolysin is the most important toxin in the enteropathogenic mechanism of non-O1 V. cholerae.

Animals↗

PubMed1991

[Comparison between the aged and children of the normal distribution of pharyngeal and intestinal hemolytic streptococci].

A marked difference between the aged and children has been observed in the group distribution of hemolytic streptococci isolated from various clinical specimens. Group B strains from the urine and sputum, and group G from the sputum, pus and exudate have been predominant in the aged, whereas group A strains from the throat swab have dominated in children. The present study was undertaken to clarify the background for such a marked difference by investigating the normal state of pharyngeal and intestinal carriage of hemolytic streptococci both in the aged and children. 1. As to the pharyngeal carriage, quite a contrast was observed between the aged and children. In the former, the rate of carries was low and the predominant groups among the streptococcus isolates were B (Streptococcus agalactiae) and G (identified as Streptococcus equisimilis), while in the latter, the rate was high and group A (Streptococcus pyogenes) strains comprised approximately 75% of the isolates, most of them being from the throat swab. 2. Both the aged and children showed a similar state of streptococcus carriage in the intestine. The rate of carriers was low and the predominant group among the isolates was B in both populations. Although group G strains were occasionally isolated, group A strains were isolated neither in the aged nor in children. These results explain well the difference between the aged and children in the group distribution of the clinical isolates of hemolytic streptococci.

Age Factors↗

PubMed1991

Partial restriction map of salmonid herpesvirus (Oncorhynchus masou virus) DNA for three restriction enzymes BamHI, EcoRI and XhoI.

Cleavage of Oncorhynchus masou virus (OMV) DNA with restriction endonucleases BamHI, EcoRI, and XhoI resulted in 28, 26 and 17 fragments, respectively. Based on the molecular weights of digested fragments and those molar ratio. OMV DNA showed the molecular weight of about 100 x 10(6). Twenty out of 28 BamHI fragments of OMV DNA were successfully cloned into pBR322 vector. Restriction map of OMV DNA was constructed by blotting hybridization and double-digestion. The data suggested that terminal repeat of the end fragments of OMV DNA molecule was not existence.

Animals↗

PubMed1991

The early pathogenesis in chicken inoculated with non-pathogenic serotype 2 Marek's disease virus.

A newly cloned serotype 2 Marek's disease virus (MDV), strain ML-6, was inoculated via the nasal cavity in specific-pathogen-free chicks to examine early virus replication and the expression of Marek's disease (MD)-related antigens. Following inoculation, viral intracellular antigens (VIAs) were detected in lymphoid organs (bursas and spleens) between 5 and 14 days post inoculation (PI), in feather follicles between 14 and 30 days PI, and in lungs at 3 days PI by the immunohistopathological staining of avidin-biotin-peroxidase complex method. But, very few VIAs were expressed in the thymuses between 5 and 14 days PI. However, MD tumor-associated surface antigens were not detected in any organs. Viruses were isolated from separated spleen cells at 14 and 30 days PI. Fluorescent antibodies of convalescent sera were also detected after 10 days PI. As most of the VIAs were detectable in B-cells in bursas and spleens. B-cells were considered to be the main first target cells for the serotype 2 MDV infection.

Animals↗