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Biomedical subjects

K Nagaoka

Publications and source records attributed to K Nagaoka.

At least 37 records · Page 2Linked to original sources
PubMed1997

Laboratory-scale bioremediation of oil-contaminated soil of Kuwait with soil amendment materials.

A huge amount of oil-contaminated soil remains unremediated in the Kuwait desert. The contaminated oil has the potentiality to cause pollution of underground water and to effect the health of people in the neighborhood. In this study, laboratory scale bioremediation experiments were carried out. Hyponex (Hyponex, Inc.) and bark manure were added as basic nutrients for microorganisms, and twelve kinds of materials (baked diatomite, microporous glass, coconut charcoal, an oil-decomposing bacterial mixture (Formula X from Oppenheimer, Inc.), and eight kinds of surfactants) were applied to accelerate the biodegradation of oil hydrocarbons. 15% to 33% of the contaminated oil was decomposed during 43 weeks' incubation. Among the materials tested, coconut charcoal enhanced the biodegradation. On the contrary, the addition of an oil-decomposing bacterial mixture impeded the biodegradation. The effects of the other materials were very slight. The toxicity of the biodegraded compounds was estimated by the Ames test and the tea pollen tube growth test. Both of the hydrophobic (dichloromethane extracts) and hydrophilic (methanol extracts) fractions showed a very slight toxicity in the Ames test. In the tea pollen tube growth test, the hydrophobic fraction was not toxic and enhanced the growth of pollen tubes.

Biodegradation, Environmental↗
PubMed1997

A study on the beryllium lymphocyte transformation test and the beryllium levels in working environment.

The relationship between airborne concentration of beryllium in the working environment and workers' beryllium lymphocyte transformation test (Be-LTT) values was examined based on data obtained from a four-year survey (1992-1995) conducted at beryllium-copper alloy manufacturing factories. This study showed that the T cells of workers continuously exposed to beryllium of more than 0.01 microgram/m3 could be activated and that the cell-mediated immune response of workers could be promoted. On the other hand, the Be-LTT of workers exposed to beryllium levels of less than 0.01 microgram/m3 was shown to be unaffected by beryllium. These findings suggest that beryllium sensitization is not manifested when level of beryllium in working environment are less than 0.01 microgram/m3. Therefore, in such cases workers do not develop Chronic beryllium disease (CBD). We concluded that the Be-LTT can be applied as a medical indicator to detect the development of CBD.

Adult↗
PubMed1995

A new surgical method for canine congenital patellar luxation.

Canine patellar luxation is seen in toy and miniature breeds, and in the majority of cases the problem is medial patellar luxation. When the luxation is left alone, it causes deformity and disorder in the growth of the affected limb. In severe cases, the limb may cease to afunction. Early surgical correction is therefore essential, but the owners are not able to detect the disorder at an early age and surgical intervention in most cases will take place after 6 months of age. The authors were able to have the opportunity to operate at an earlier age by educating breeders and owners. Various techniques have been developed and implemented to correct this disorder with varying therapeutic results. The authors have devised a unique surgical method which has been applied to the numerous cases with good results since 1985. The procedure is to make a longitudinal groove on the medical cortical bone of the tibial tuberosity along the tibial crest, and to place small pieces of artificial ceramic bone or autoplastic bone grafts in the groove, thus laterally transposing the tibial tuberosity and crest. This method makes it possible to put the quadriceps muscles of the thigh, the patella and the patellar ligament in the correct alignment over the femoral trochlea. It is considered appropriate to conduct this operation at 1.0-3.0 months of age when the dog has matured enough to be able to withstand anesthesia and surgical stress.

Animals↗
PubMed1995

[Allergy histories of Brazilian residents of Japanese descent in Japan].

A questionnaire written in Portuguese was administered from December 1993 to February 1994 to study the frequency of allergic symptoms among Brazilians of Japanese descent in Japan. The results obtained were as follows. 1) The frequencies of allergy histories were 18% for allergic rhinitis, 14% for atopic dermatitis, 12% for alimentary allergy, 10% for allergic conjunctivitis, 9% for allergy to metals, 8% for drug allergy, 7% each for urticaria and pollinosis, and 5% for asthma. 2) The frequencies of allergic rhinitis, allergic conjunctivitis, pollinosis, urticaria and drug allergy were higher among those who came from metropolitan districts in Brazil with severe environmental pollution compared to those who came from rural districts. 3) The characteristics of persons who had subjective symptoms of pollinosis in early spring during their stay in Japan were as follows: The districts they resided in while in Japan were in the Kanto area where the frequencies of Japanese-cedar pollen-specific IgE antibodies positives were high and also where the frequencies of Japanese cedar pollinosis were high among Japanese living in Japan. The districts they originally came from were the metropolitan areas in Brazil, and they were resident in Japan for more than one year.

Adult↗
PubMed1994

[Comparative study on placental transfer and maternal distribution of organic and inorganic tin following oral administration in pregnant rats].

Placental transfer and body distribution of triphenyl tin chloride (TPTC) and tin chloride (SnCl2) were investigated in pregnant rats. Pregnant wistar rats were orally administered TPTC at 0, 1.0 and 2.0 mg/rat/day during 6-10 and 14-18 days of gestation, and with SnCl2 at 0 and 20 mg/rat/day on 7, 10 and 15 days of gestation (group treated 3 times) or 6-10 and 13-16 days of gestation at 0 and 20 mg/rat/day (group treated 9 times). On day 20 of gestation in rats treated with TPTC, and day 17 in rats with SnCl2, fetuses, placentas, maternal blood and organs were obtained for analyses. Mean fetal tin levels from rats treated with 1.0 and 2.0 mg TPTC were 0.05 and 0.11 microgram/g wet weight, respectively, these values being significantly (P < 0.01) higher than in the control group. The latter was higher than the former at a significance level of 5%. No significant difference between fetal tin levels from rats treated with SnCl2 and the control group could be detected. Following oral TPTC administration, tin was present in maternal liver, kidney and brain in high concentrations. Following the oral administration of SnCl2, the tin level was highest in bone and kidney, but none could be detected in the brain.

Administration, Oral↗
PubMed1994

Characterization of Haemophilus paragallinarum isolated in the Philippines.

In 1989 and 1990, we isolated five strains of Haemophilus paragallinarum in the Philippines. Serological studies were done on three of these isolates. The results of haemagglutination, reactability to monoclonal antibodies and cross immunization with standard strains showed that they belonged to serotypes A, B and C respectively. This is the first report on the isolation of H. paragallinarum and on a related serological study in the Philippines.

Animals↗
PubMed1994

[Prevalence of specific IgE antibodies for Dermatophagoides farinae and six inhalants in the general population].

A seroepidemiologic study of house dust allergy and pollinosis was performed among a general population aged 17 to 69 in Aichi Prefecture, Japan. The prevalence of blood containing IgE antibodies to four perennial antigens and three seasonal antigens was examined among 198 persons whose serum total IgE antibodies were above 40 IU/ml. The prevalence of blood containing IgE antibodies was from 9 to 18 percent among perennial antigens and from 6 to 30 percent among seasonal antigens. These results show that Dermatophagoides farinae, Cryptomeria japonica pollen and Anthoxanthumodoratum pollen are important antigens in this population.

Adolescent↗
PubMed1991

The bialaphos biosynthetic genes of Streptomyces viridochromogenes: cloning, heterospecific expression, and comparison with the genes of Streptomyces hygroscopicus.

The bialaphos resistance gene, bar, was used as a selectable marker to isolate the bialaphos production genes (bap) from the Streptomyces viridochromogenes genome. The S. viridochromogenes bar gene was cloned on overlapping restriction fragments using pIJ680 and pIJ702 in the bialaphos-sensitive host, S. lividans. Although the restriction endonuclease cleavage map of these fragments was not similar to the bap cluster of S. hygroscopicus, the presence and location of bar and four other bap genes as well as a gene required for the transcriptional activation of the cluster (brpA) was demonstrated by heterologous cloning experiments using a series of previously characterized bialaphos-nonproducing S. hygroscopicus mutants. Since recombination-deficient mutants of streptomycetes have not been isolated, restored function provided by cloned homologous DNA results from both recombination (marker rescue) and complementation in trans. In contrast to our previously reported homologous cloning experiments where we were able to define the position of mutant alleles by recombination, in these heterologous cloning experiments we observed little if any recombination between plasmid-cloned genes and the chromosome. As a result, this approach allowed us to define the location and orientation of functional genes using a genetic complementation test. The organization of the clustered S. viridochromogenes bap genes was indistinguishable from the corresponding S. hygroscopicus mutant alleles. The fact that the S. viridochromogenes transcriptional regulatory gene, brpA, functioned in S. hygroscopicus implied that some transcriptional regulatory signals may also be interchangeable. In these two Streptomyces species, which have considerable nucleotide sequence divergence, the complex biochemical and genetic organization of the bialaphos biosynthetic pathway is conserved.

Anti-Bacterial Agents↗
PubMed1991

Conversion of bialaphos to other oligopeptides containing phosphinothricin by Streptomyces hygroscopicus.

Two oligopeptides containing phosphinothricin were accumulated in the culture of bialaphos (BA) producer Streptomyces hygroscopicus SF1293 when large amount of BA was added to the culture at idio phase. One of the oligopeptides was a new substance, BA dimer (phosphinothricyl-alanyl-alanyl-phosphinothricyl-alanyl-alan ine), and the other was a known substance called If (phosphinothricyl-alanyl-alanyl-phosphinothricin). Though BA none producing mutants which were blocked at the steps 1, 10 and 13, respectively in BA biosynthesis also converted BA to BA dimer and If, the mutants blocked at the step 11 (alanylation) could not curry out the conversion. Antibiotic activities of BA dimer and If were lower than 1/100 of BA.

Aminobutyrates↗
PubMed1990

Carboxyphosphonoenolpyruvate phosphonomutase, a novel enzyme catalyzing C-P bond formation.

An enzyme catalyzing the formation of an unusual C-P bond that is involved in the biosynthesis of the antibiotic bialaphos (BA) was isolated from the cell extract of a mutant (NP71) of Streptomyces hygroscopicus SF1293. This enzyme, carboxyphosphonoenolpyruvate (CPEP) phosphonomutase, was first identified as a protein lacking in a mutant (NP213) defective in one of the steps in the pathway to BA. The first 30 residues of the amino terminus of this protein were identical to those predicted by the nucleotide sequence of the gene that restored BA production to NP213. The substrate of the enzyme, a P-carboxylated derivative of phosphoenolpyruvate named CPEP, was also isolated from the broth filtrate of NP213 as a new biosynthetic intermediate of BA. CPEP phosphonomutase catalyzes the rearrangement of the carboxyphosphono group of CPEP to form the C-P bond of phosphinopyruvate.

Anti-Bacterial Agents↗
PubMed1990

Streptomyces hygroscopicus has two glutamine synthetase genes.

Streptomyces hygroscopicus, which produces the glutamine synthetase inhibitor phosphinothricin, possesses at least two genes (glnA and glnB) encoding distinct glutamine synthetase isoforms (GSI and GSII). The glnB gene was cloned from S. hygroscopicus DNA by complementation in an Escherichia coli glutamine auxotrophic mutant (glnA). glnB was subcloned in Streptomyces plasmids by insertion into pIJ486 (pMSG3) and pIJ702 (pMSG5). Both constructions conferred resistance to the tripeptide form of phosphinothricin (bialaphos) and were able to complement a glutamine auxotrophic marker in S. coelicolor. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis of S. lividans(pMSG5) revealed a highly overexpressed 40-kilodalton protein. When GS was purified from this strain, it was indistinguishable in apparent molecular mass from the 40-kilodalton protein. The nucleic acid sequence of the cloned region contained an open reading frame which encoded a protein whose size, amino acid composition, and N-terminal sequence corresponded to those of the purified GS. glnB had a high G + C content and codon usage typical of streptomycete genes. A comparison of its predicted amino acid sequence with the protein data bases revealed that it encoded a GSII-type enzyme which had previously been found only in various eucaryotes (47 to 50% identity) and nodulating bacteria such as Bradyrhizobium spp. (42% identity). glnB had only 13 to 18% identity with eubacterial GSI enzymes. Southern blot hybridization experiments showed that sequences similar to glnB were present in all of the five other Streptomyces species tested, as well as Frankia species. These results do not support the previous suggestion that GSII-type enzymes found in members of the family Rhizobiaceae represent a unique example of interkingdom gene transfer associated with symbiosis in the nodule. Instead they imply that the presence of more than one gene encoding GS may be more common among soil microorganisms than previously appreciated.

Amino Acid Sequence↗
PubMed1990

Biochemical mechanisms of C-P bond formation of bialaphos: use of gene manipulation for the analysis of the C-P bond formation step.

One of the three C-P bond formation steps, defined as step 5 in the bialaphos (BA) biosynthetic pathway, was analyzed using a new BA non-producing mutant NP71. The mutant was derived from a BA producer by gene replacement of an unidentified region next to the gene responsible for the step 5 deficiency of the mutant NP213, obtained by conventional mutation procedures. Biochemical analysis of these two mutants indicated that NP71 was defective in the formation of carboxyphosphonoenolpyruvate (CPEP), while NP213 lacked the enzyme CPEP phosphonomutase, which catalyzed the intramolecular rearrangement of CPEP.

DNA↗
PubMed1990

[A case of Reiter's disease with severe skin manifestations successfully treated with oral etretinate].

A case of Reiter's syndrome with severe keratoderma being successfully treated with oral Etretinate is reported. A 38 year-old man was referred to our hospital in December, 1985 for treatment of refractory skin eruptions and polyarthralgia. He previously experienced urethritis in December, 1983 with subsequent development of high fever, balanitis, skin eruptions and polyarthritis. Treatments with antibiotics, anti-inflammatory drugs and glucocorticoids were ineffective at that time. The patient was diagnosed as Reiter's syndrome based on his clinical symptoms and the presence of HLA-B27. He was treated in our clinic with oral administration of Etretinate, aromatic retinoids, at the initial doses of 40 mg/day with subsequent increase up to 75 mg/day in 2 weeks. This maintenance dose was continued for two months, resulted in improvements of joint pain, skin eruptions and the laboratory abnormalities. The doses of Etretinate was gradually decreased and then was discontinued after 4 months, when approximately 90% of the skin lesion disappeared. No noticeable side-effect was observed except slight stomatitis. The remission continued for about 2 and half years after cessation of Etretinate without any medication. However, evidence of relapse with the same skin lesions and arthralgia was observed in March, 1989. A repeated treatment with oral Etretinate was attempted with similar but slightly delayed effects.

Adult↗
PubMed1989

Production and some properties of monoclonal antibodies against serotype strains of Pseudomonas aeruginosa.

A set of 16 serotype specific monoclonal antibodies (MoAbs) against Pseudomonas aeruginosa classified by Homma were obtained by the mouse hybridoma technique. This set of MoAbs was useful for classification of their serotypes especially O-antigen groups G and M. MoAb obtained from serotype 15 of Homma's classification reacted with serotype 17 of the same classification. We also obtained two MoAbs which reacted with 7 Homma's serotypes of 6 different O-antigen groups and one MoAb which recognized all 4 Homma's serotypes of O-antigen group B. These MoAbs were also useful in mice for the preventive effect against the infections of P. aeruginosa.

Animals↗