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Biomedical subjects

K Komiyama

Publications and source records attributed to K Komiyama.

At least 73 records · Page 4Linked to original sources
PubMed1993

Antitumor activity of a novel nucleotide derivative, 5'-(1,2-dipalmitoyl-sn-glycero-3-phospho)-5-fluorouridine (TJ14026) on murine tumors.

The antitumor activity of a nucleotide derivative, 5'-(1,2-dipalmitoyl-sn-glycero-3-phospho)-5-fluorouridine (TJ14026), was confirmed following both intraperitoneal and oral administration against a number of murine experimental tumor systems in vivo, which included Meth A fibrosarcoma, B16 melanoma, 5-fluorouracil (5-FU) resistant P388 leukemia, P815 mastocytoma and L5178Y-ML lymphoma. Successive i.p. injections of a small dose (10 mg/kg/d x 10) or intermittent i.p. injections of a larger dose (50 mg/kg/d x 3) were equally effective against the solid form of Meth A fibrosarcoma. Intraperitoneal injection of TJ14026 prolonged the life of mice with 5-FU resistant P388 leukemia. Oral administration of TJ14026 was also effective against P815 mastocytoma and L-5178Y-ML lymphoma in the liver, an P388 leukemia metastasized to the lymph nodes. Glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) levels were elevated in the serum of un-treated mice bearing P815 mastocytoma but not in mice treated with TJ14026.

Administration, Oral↗
PubMed1993

Amelanotic melanoma of the oral cavity.

A case of amelanotic melanoma arising in the upper molar region, which was difficult to diagnose histologically, is reported. The patient was a 79-year-old woman, who complained of a painful swelling in the gingiva of the left upper molar region. Routine histological examination showed that the lesion was composed of diffusely scattered atypical cells with round, spindle-shaped and irregular nuclei and scanty fibrous connective tissue. A fascicular arrangement was often found in the lesion, and no cancer nests were observed. Immunohistochemical study demonstrated positive staining for S-100 protein in both the nuclei and cytoplasm of the tumor cells. Electron microscopic examination revealed that cell organelles were abundant, and an interrupted basal lamina was often found along the cell membrane. The preliminary diagnosis was a non-epithelial malignant tumor. After surgery, histological examination of metastases in lymph nodes from the submandibular region revealed that the tumor cells contained melanin pigment in the cytoplasm, as confirmed by Masson's melanin stain. The final pathological diagnosis was therefore amelanotic melanoma. Immunohistochemical staining for S-100 protein may be useful for differential diagnosis of amelanotic melanoma in conjunction with electron microscopic examination.

Aged↗
PubMed1993

New inhibitors of melanogenesis, OH-3984 K1 and K2. I. Taxonomy, fermentation, isolation and biological characteristics.

Melanogenesis inhibitors, OH-3984 K1 and K2 were isolated from fermentation broth of Streptomyces sp. OH-3984. OH-3984 K1 and K2 inhibited the melanogenesis of B16 melanoma cells at concentrations of 7.5 and 3.8 micrograms/ml, respectively, whereas inhibition of tyrosinase activity has not been observed. The microbial metabolites showed no antimicrobiological activities against Gram-positive and Gram-negative bacteria, fungi or yeast at a concentration of 1,000 micrograms/ml.

Anti-Bacterial Agents↗
PubMed1993

New inhibitors of melanogenesis, OH-3984 K1 and K2. II. Physico-chemical properties and structural elucidation.

New melanin synthesis inhibitors, OH-3984 K1 and K2, were isolated from the fermentation broth of Streptomyces sp. OH-3984, and their structures were elucidated by spectroscopic methods and by chemical transformations. OH-3984 K1 (M.W.: 306; C18H26O4) and K2 (M.W.: 308; C18H28O4) have unique gamma-lactone rings, both of which correspond to oxidative products derived from C1-O14 cleavage of the 14-membered lactone group.

Anti-Bacterial Agents↗
PubMed1993

A new antibiotic, cypemycin. Taxonomy, fermentation, isolation and biological characteristics.

A new peptide antibiotic, cypemycin, with a molecular weight of 2,097 (M+H), was isolated from the culture broth of Streptomyces sp. OH-4156. The antibiotic possesses cytocidal activity against P388 leukemia cells in vitro at a concentration of 1.3 microgram/ml (IC50 values), and the antibiotic showed antimicrobial activities against Micrococcus luteus (MIC, 0.2 microgram/ml).

Amino Acid Sequence↗
PubMed1992

Increased expression of Epstein-Barr virus in primary biliary cirrhosis patients.

Peripheral blood mononuclear cells (PBMC, n = 26), formalin-fixed paraffin-embedded liver tissues (n = 11) and saliva (n = 15) of primary biliary cirrhosis (PBC) patients were used for the detection of Epstein-Barr virus (EBV) sequences by polymerase chain reaction (PCR) assay. The semiquantitative analysis of EBV-DNA was also carried out in a reconstructive experiment using an EBV-infected cell line. The PBMCs of PBC patients showed increased levels of EBV-DNA (61%) in contrast to chronic active hepatitis patients (19%), liver cirrhosis patients (14%) and healthy individuals (11%). Furthermore, formalin-fixed paraffin-embedded liver tissues, as well as saliva from PBC patients, also demonstrated increased levels of EBV-DNA when compared to healthy individuals and those with other liver diseases. The increased levels of EBV-DNA in the PBMC, liver tissue and saliva of the PBC patients suggest that those patients may have a depressed immune function against EBV infection.

Adult↗
PubMed1992

Clinical evaluation of a light energy conversion toothbrush.

A blind, two-way crossover clinical trial was carried out to compare the effectiveness of plaque removal between a new, light energy conversion toothbrush incorporated with a semiconductor of TiO2 (test) and a similar toothbrush without the semiconductor (control). The study was completed by 73 school children aged 13-15 years. Each toothbrush was used for a period of 3 weeks. The mean differences between baseline plaque scores and after subjects used the test and control brushes were analyzed by the paired t-test. The Soladey 2 toothbrush showed significantly more reduction of plaque on the buccal surfaces of all teeth than the control brush. There was no significant difference in the plaque removing ability of the two brushes on the lingual aspects of the mandible and on the lingual surfaces of the maxillary posterior sextant. As the buccal surfaces are more likely to allow light to reach the semiconductor during brushing than the lingual areas, it is possible that the reported photocatalytic property of the semiconductor may be involved in some way in the observed reduction of plaque.

Adolescent↗
PubMed1992

The role of saliva in aggregation and adherence of Pseudomonas aeruginosa in patients with cystic fibrosis.

The aggregation and adherence activity of P. aeruginosa, mediated by whole saliva from cystic fibrosis (CF) patients and non-CF subjects, was investigated. CF saliva-mediated aggregation of P. aeruginosa was stronger than the activity of non-CF saliva. Likewise, P. aeruginosa adherence to buccal epithelial cells (BEC) of CF patients was stronger than to BEC of non-CF subjects. Adherence of non-mucoid P. aeruginosa to BEC of CF patients was increased by saliva, whereas the mucoid variant was not. CF patients colonized with P. aeruginosa showed higher adherence of the non-mucoid variant than non-colonized CF patients. CF patients with high saliva-mediated adherence of non-mucoid P. aeruginosa also had high salivary aggregation activity. Increased CF saliva-mediated aggregation activity may be linked to the increased non-mucoid P. aeruginosa adherence to BEC of CF patients.

Adolescent↗
PubMed1992

Acid production by Actinomyces viscosus of root surface caries and non-caries origin during glycogen synthesis and degradation at different pH levels.

Actinomyces viscosus strains, freshly isolated from root surface caries lesions and intact root surfaces, were studied for their glycogen synthetic and degradative activities at pH 4.5, 5.0, and 7.0 in a pH-stat. At all three pH levels, root caries origin of A. viscosus synthesized up to three times as much glycogen compared to non-root caries origin. Since root caries origin of A. viscosus strains initially synthesized large amounts of glycogen, a longer period of time was required to deplete this polymer, resulting in an extended period of acid production, even at pH 4.5 and pH 5.0. This study suggests that the ability of A. viscosus of root caries origin to synthesize large quantities of glycogen and subsequently degrade this stored polymer slowly with acid production, at acidic pH levels, may play an important role in the root caries process.

Acids↗
PubMed1992

A case of eosinophilic granuloma arising in the mandible.

Eosinophilic granuloma is a disease of the reticuloendothelial system and its pathogenesis is not yet completely clear. The histopathological findings are granulomatous proliferation of histiocytes accompanied by diffuse infiltration of eosinophils. We recently experienced a case of eosinophilic granuloma arising monostotically in the body of the mandible in the 76 [symbol: see text] region. There has been no local recurrence 17 months after surgical removal of the lesion.

Adolescent↗
PubMed1992

A case of adenocarcinoma arising in the upper lip.

A case of adenocarcinoma arising in the lip of a 20-year-old Japanese man is reported. After electro-irradiation therapy with a dose of 30 Gy, one third of the upper lip, including part of the cheek, was excised. Immediate reconstruction using transpositional flaps of the buccal skin and mucosa, and a functional neck dissection were performed. Nineteen months after surgery, there was no local recurrence or distant metastasis, and desirable results were obtained both functionally and cosmetically.

Adenocarcinoma↗
PubMed1992

[Changes on hosts' immunological response in HCC patients treated with transcatheter arterial embolization (TAE)].

In order to investigate the changes of hosts' immunological response against cancer treated with transcatheter arterial embolization (TAE), percent change of surface antigens of peripheral lymphocytes using two color analysis with flow cytometry and NK activity were measured before TAE and 1,2 and 3 weeks after TAE in 41 cases with hepatocellular carcinoma. CD4+2H4+ subset (suppressor inducer cell) significantly increased 1 week after TAE and the increase significantly continued for 3 weeks. CD8+CD11b+ bright subset (suppressor cell), CD8+CD11b- subset (cytotoxic T cell) and CD4+2H4- subset (helper/helper inducer cell) did not change significantly for 3 weeks after TAE. Total of CD16+Leu7-, CD16+Leu7+ and CD16-Leu7+ subsets (NK cell subsets) significantly decreased 1 week after TAE and the decrease significantly continued for 3 weeks. NK activity was significantly suppressed 1 week after TAE, and the suppression of NK activity significantly continued for 3 weeks. It was identified that decrease of NK cell subsets was significantly related to increase of suppressor inducer cell by statistical multivariate analysis. In NK cell subsets composited ratio of CD16-Leu7+ significantly increased 1 week after TAE, of CD16+Leu7+ significantly decreased 1 week after TAE, and of CD16+Leu7- significantly decreased 2 week after TAE. Therefore it is suggested that patients' immunity against cancer is weakened by TAE, and that TAE should not be rashly done in order to preserve the immunological response when it is previously expected that patients might have residual cancer; metastasis or invasion into vessels after TAE.

Adult↗
PubMed1992

Surface disinfection of saliva-contaminated dental X-ray film packets.

A study was undertaken to determine the most effective method for the surface disinfection of saliva-contaminated dental X-ray film packets. Size 2 Kodak Poly-Soft film packets were placed in the oral cavities of patients and "sham" irradiated. After removal from the oral cavity, some of these packets were left untreated before being placed in transfer vials containing transport medium. Other packets were handled in one of three different ways before being placed in the transfer vials: 1) wiped with a piece of sterile tissue paper to remove visible saliva; 2) wiped once with a sterile piece of gauze soaked with disinfectant and then immediately wiped dry with a piece of tissue paper ("one-wipe" surface-disinfection technique); or, 3) wiped twice with a sterile piece of gauze soaked with disinfectant and allowed to air dry ("two-wipe" surface-disinfection technique). The transport medium was serially diluted and microbiological processing completed to obtain bacterial counts corresponding to the levels of bacterial contamination of the film packet surfaces. The two-wipe surface-disinfection method effectively eliminated bacterial contamination of the film packets, with all of the disinfectants tested being equally effective. The one-wipe technique, using disinfectant, appeared to be slightly less effective. Mere physical removal of the saliva from the film packet, without the use of disinfectant, was the least effective method.

Bacteria, Aerobic↗
PubMed1991

Studies on glycosylation of the mitomycins. Syntheses of 7-N-(4-O-glycosylphenyl)-9a-methoxymitosanes.

Two new derivatives of glycosyl mitomycin C, 7-N-[4-O-(beta-D-glucopyranosyl and alpha-sialosyl)phenyl]-9a- methoxymitosanes, were synthesized, and their structures were elucidated by analysis of the nuclear magnetic resonance spectra. Field desorption mass spectrometry was successfully used for the confirmation of these structures. The cytotoxic, antibacterial, and antitumor activities of 7-N-(4-glycosylphenyl)-9a- methoxymitosanes were also examined.

Animals↗