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Biomedical subjects

M Kataoka

Publications and source records attributed to M Kataoka.

At least 19 recordsLinked to original sources
PubMed2007

Regulation of calprotectin expression by interleukin-1alpha and transforming growth factor-beta in human gingival keratinocytes.

BACKGROUND AND OBJECTIVE: Calprotectin, a heterodimer of S100A8 and S100A9 with antimicrobial properties, is expressed in gingival keratinocytes and plays an important role in innate immunity. Because calprotectin expression is localized in the spinous cell layer of the gingival epithelium, we hypothesized that the expression of calprotectin in keratinocytes is related to the differentiation stage. The aim of the present study was to investigate the relationship between calprotectin expression and keratinocyte differentiation using some factors that regulated its differentiation. MATERIAL AND METHODS: Normal human gingival keratinocytes were isolated from gingival tissues obtained at the extraction of wisdom teeth, and were cultured in serum-free keratinocyte medium supplemented with interleukin-1alpha or calcium, which promote keratinocyte differentiation, and transforming frowth factor-beta (TGF-beta) or retinoic acid, which suppress its differentiation. The expression of S100A8/A9 mRNA and the production of calprotectin in normal human gingival keratinocytes were examined by northern blotting and enzyme-linked immunosorbent assay, respectively. The expression of cytokeratin 14, involucrin and filaggrin (marker proteins of keratinocyte differentiation) was investigated by immunohistochemical staining, and the DNA-binding activity of CCAAT/enhancer binding protein alpha (C/EBPalpha), a transcription factor, was examined by electrophoretic mobility shift assay. RESULTS: The expression of S100A8/A9 mRNA and the production of calprotectin were increased by interleukin-1alpha and calcium, but decreased by TGF-beta. RA inhibited the expression of S100A8/A9 and keratinocyte differentiation, which were induced by interleukin-1alpha. C/EBPalpha DNA-binding activity in normal human gingival keratinocytes was enhanced by interleukin-1alpha and calcium, but suppressed by TGF-beta. CONCLUSION: The present study suggests that calprotectin expression is related to keratinocyte differentiation and that C/EBPalpha is a regulator of calprotectin expression in keratinocytes.

CCAAT-Enhancer-Binding Protein-alpha↗
PubMed2006

Gene expression of Corynebacterium glutamicum in response to the conditions inducing glutamate overproduction.

AIM: The ultimate aim is to elucidate the molecular mechanisms for glutamate overproduction by Corynebacterium glutamicum. METHODS AND RESULTS: Gene expression in response to the conditions inducing glutamate overproduction was investigated by using a DNA microarray technique. Most genes involved in the EMP pathway, the PPP, and the TCA cycle were downregulated, while five genes that were highly upregulated (NCgl0917, NCgl2944, NCgl2945, NCgl2946, and NCgl2975) were identified under all the three conditions for overproduction that are studied here. Gene products of NCgl2944, NCgl2945, and NCgl2946 were highly homologous to each other, did not resemble any other protein, and have remained uncharacterized thus far. The product of NCgl0917 showed a similarity to a few hypothetical and uncharacterized proteins. NCgl2975 was homologous to metal-binding proteins. CONCLUSIONS: The decrease in the activity of 2-oxoglutarate dehydrogenase complex, a key enzyme that is downregulated during glutamate overproduction, can be mainly attributed to the downregulation of odhA and sucB. Five highly upregulated genes were also identified. SIGNIFICANCE AND IMPACT OF THE STUDY: Although fermentative production of glutamate has been carried out for more than 45 years, information on the molecular mechanisms of glutamate overproduction is still limited. This study further elucidates these mechanisms.

Citric Acid Cycle↗
PubMed2006

A novel NADP+-dependent L-1-amino-2-propanol dehydrogenase from Rhodococcus erythropolis MAK154: a promising enzyme for the production of double chiral aminoalcohols.

AIM: A novel NADP(+)-dependent L-1-amino-2-propanol dehydrogenase was isolated from Rhodococcus erythropolis MAK154, and characterized. METHODS AND RESULTS: The enzyme was inducibly produced on cultivation with aminoalcohols such as 1-amino-2-propanol, 1-amino-2-butanol and 2-aminocyclohexanol. The enzyme catalyses the NADP(+)-dependent oxidation of several aminoalcohols, and also the NADPH-dependent asymmetric reduction of an aminoketone compound to a double chiral aminoalcohol, d-pseudoephedrine. Amino acid sequence analysis showed that the enzyme might belong to the short-chain dehydrogenase/reductase family. CONCLUSIONS: NADP(+)-dependent L-1-amino-2-propanol dehydrogenase isolated from R. erythropolis MAK154 reversibly catalysed dehydrogenation of aminoalcohols, and exhibited a unique sterospecifity for the reduction reaction. SIGNIFICANCE AND IMPACT OF THE STUDY: The enzyme is a promising catalyst for the production of double chiral compound, d-pseudoephedrine, from prochiral substrate.

Alcohol Dehydrogenase↗
PubMed2005

Effect of millimeter waves on natural killer cell activation.

Millimeter wave therapy (MMWT) is being widely used for the treatment of many diseases in Russia and other East European countries. MMWT has been reported to reduce the toxic effects of chemotherapy on the immune system. The present study was undertaken to investigate whether millimeter waves (MMWs) can modulate the effect of cyclophosphamide (CPA), an anticancer drug, on natural killer (NK) cell activity. NK cells play an important role in the antitumor response. MMWs were produced with a Russian-made YAV-1 generator. The device produced modulated 42.2 +/- 0.2 GHz radiation through a 10 x 20 mm rectangular output horn. Mice, restrained in plastic tubes, were irradiated on the nasal area. Peak SAR at the skin surface and peak incident power density were measured as 622 +/- 100 W/kg and 31 +/- 5 mW/cm2, respectively. The maximum temperature elevation, measured at the end of 30 min, was 1 degrees C. The animals, restrained in plastic tubes, were irradiated on the nasal area. CPA injection (100 mg/kg) was given intraperitoneally on the second day of 3-days exposure to MMWs. All the irradiation procedures were performed in a blinded manner. NK cell activation and cytotoxicity were measured after 2, 5, and 7 days following CPA injection. Flow cytometry of NK cells showed that CPA treatment caused a marked enhancement in NK cell activation. The level of CD69 expression, which represents a functional triggering molecule on activated NK cells, was increased in the CPA group at all the time points tested as compared to untreated mice. However, the most enhancement in CD69 expression was observed on day 7. A significant increase in TNF-alpha level was also observed on day 7 following CPA administration. On the other hand, CPA caused a suppression of the cytolytic activity of NK cells. MMW irradiation of the CPA treated groups resulted in further enhancement of CD69 expression on NK cells, as well as in production of TNF-alpha. Furthermore, MMW irradiation restored CPA induced suppression of the cytolytic activity of NK cells. Our results show that MMW irradiation at 42.2 GHz can up-regulate NK cell functions.

Animals↗
PubMed2005

Evaluation of mRNA expression of human drug-metabolizing enzymes and transporters in chimeric mouse with humanized liver.

The hepatic mRNA expression of human drug-metabolizing enzymes and transporters in chimeric mise with almost-completely humanized liver (replacement index: 71-89%) was investigated. The mRNAs of 58 human phase I enzymes, 26 human phase II enzymes, 23 human transporters, and five mouse Cyps were measured in the chimeric mice with humanized liver generated using hepatocytes from a Japanese donor. The mRNA expression of 52 human phase I enzymes, which includes 20 human CYPs, 26 human phase II enzymes and 21 human transporters was ascertained in the chimeric mouse liver. Among them, the expression of the target mRNAs vital for liver function such as the metabolism and secretion of endogenous compounds appeared to be maintained. The central value for the expression ratio in all target genes in chimeric mouse liver to the donor liver was 0.46, which was lower than the substitution rate of chimeric mouse liver by donor liver. The ratio of mouse Cyp mRNA expression of chimeric mouse liver to that of control mouse liver was 0.19 or less, except for that of Cyp2b10. There were good correlations between the mRNA expression levels of human hepatic albumin gene, the values of the rate of replacement of mouse liver by human liver, and the human blood albumin concentration in the chimeric mice. The chimeric mice with humanized liver may be a useful tool for the evaluation of drug-drug interactions such as the inhibition and induction of drug-metabolizing enzymes and transporters.

Animals↗
PubMed2005

Alpha 2 integrin +807 polymorphism in drug-induced gingival overgrowth.

Alpha2 integrin on fibroblasts is reported to play an important role in the induction of drug-induced gingival overgrowth, which is characterized by excessive accumulation of type I collagen in gingival connective tissue. Silent polymorphism 807 T/C within the alpha2 integrin gene is associated with high/low alpha2 integrin expression. The aim of this study was to test the hypothesis that expression of alpha2 integrin 807 T/C polymorphism correlates with drug-induced gingival overgrowth. A case-control study comparing 136 subjects taking calcium channel blockers (72 with vs. 64 without drug-induced gingival overgrowth) demonstrated that the frequency of the +807 C allele was significantly higher in the case group than in the controls (odds ratio, 3.61; 95% confidence interval, 2.14 - 6.10; P < 0.05). The present findings suggest that the alpha2 +807 C allele is one of the genetic risk factors for drug-induced gingival overgrowth.

Adolescent↗
PubMed2004

MRI measurement of liver regeneration in mice following partial hepatectomy.

Improvements in noninvasive imaging modalities are crucial for preoperative in vivo assessments of liver condition and potential for regeneration after liver resection for removal of liver tumors. To that end, an MRI study of liver regeneration in mice following partial hepatectomy is described and validated. Hepatic volumes were accurately measured from contrast-enhanced, gradient-echo images of the liver. Regeneration curves were constructed for a series of mice (N = 6) from a longitudinal MR study, with images collected 1, 2, 3, 4, 5, and 9 days following surgery. We validated the MR method by correlating serial MR-measured volumes with liver wet weight. The success of this method will enable future studies to better elucidate the factors that affect regeneration, and help to optimize the timing and dosing of chemotherapeutics to minimize their deleterious effects on liver regeneration.

Animals↗
PubMed2004

Induction of calprotectin release by Porphyromonas gingivalis lipopolysaccharide in human neutrophils.

Calprotectin, a major cytosolic protein of leukocytes, is detected in neutrophils, monocytes/macrophages, and epithelial cells. This protein is known to be a marker for several inflammatory diseases and is detected in inflammatory gingival tissue with periodontal disease. Recently, we found that the calprotectin level in gingival crevicular fluid from periodontitis patients was significantly higher than that of healthy subjects. However, the regulation of calprotectin in periodontal disease is unclear. In the present study, we investigated the effect of lipopolysaccharides of periodontopathic bacteria on calprotectin release from human neutrophils. Neutrophils from healthy donors were treated with lipopolysaccharides from Porphyromonas gingivalis (P-LPS), Actinobacillus actinomycetemcomitans, Prevotella intermedia, Fusobacterium nucleatum, and Escherichia coli. Calprotectin of neutrophil was identified by immunoblotting and calprotectin amount was determined by ELISA. Two subunits (10 and 14 kDa) of calprotectin were observed in the cell and medium fractions from neutrophils. P-LPS increased calprotectin release from seven to 16 times the control level after 30 min and its effect appeared in a dose-dependent manner (10-1000 ng/ml). Lipopolysaccharides from A. actinomycetemcomitans, P. intermedia, F. nucleatum, and E. coli also induced calprotectin release from neutrophils. These results suggest that lipopolysaccharides from periodontopathic bacteria induce calprotectin release from human neutrophils.

Adult↗
PubMed2003

Coulomb blockade and kondo effect in a quantum Hall antidot.

We propose a general capacitive model for an antidot, which has two localized edge states with different spins in the quantum Hall regime. The capacitive coupling of localized excess charges, which are generated around the antidot due to magnetic flux quantization, and their effective spin fluctuation can result in Coulomb blockade, h/(2e) Aharonov-Bohm oscillations, and the Kondo effect. The resultant conductance is in qualitative agreement with recent experimental data.

Journal Article↗
PubMed2003

Gene cloning and overexpression of two conjugated polyketone reductases, novel aldo-keto reductase family enzymes, of Candida parapsilosis.

The genes encoding two conjugated polyketone reductases (CPR-C1, CPR-C2) of Candida parapsilosis IFO 0708 were cloned and sequenced. The genes encoded a total of 304 and 307 amino acid residues for CPR-C1 and CPR-C2, respectively. The deduced amino acid sequences of the two enzymes showed high similarity to each other and to several proteins of the aldo-keto reductase (AKR) superfamily. However, several amino acid residues in putative active sites of AKRs were not conserved in CPR-C1 and CPR-C2. The two CPR genes were overexpressed in Escherichia coli. The E. coli transformant bearing the CPR-C2 gene almost stoichiometrically reduced 30 mg ketopantoyl lactone/ml to D-pantoyl lactone.

4-Butyrolactone↗
PubMed2003

Novel bioreduction system for the production of chiral alcohols.

Chiral alcohols are useful intermediates for many pharmaceuticals and chemicals. Enzymatic asymmetric reduction of prochiral carbonyl compounds is a promising method for producing chiral alcohols. There have been many attempts to construct bioreduction systems for the industrial production of chiral alcohols. This review focuses on the establishment of a novel bioreduction system using an Escherichia coli transformant co-expressing genes for carbonyl reductase and cofactor-regeneration enzyme. This bioreduction system could be useful as an all-purpose catalyst for asymmetric reduction reactions.

Alcohol Oxidoreductases↗
PubMed2003

A novel enzyme, D-3-hydroxyaspartate aldolase from Paracoccus denitrificans IFO 13301: purification, characterization, and gene cloning.

A novel enzyme, D-3-hydroxyaspartate aldolase (D-HAA), catalyzing the conversion of D-3-hydroxyaspartate to glyoxylate plus glycine, was purified to homogeneity from Paracoccus denitrificans IFO 13301. D-HAA is strictly D-specific as to the alpha-position, whereas the enzyme does not distinguish between threo and erythro forms at the beta-position. In addition to D-3-hydroxyaspartate, the enzyme also acts on d-threonine, D-3-3,4-dihydroxyphenylserine, D-3-3,4-methylenedioxyphenylserine, and D-3-phenylserine. The D-HAA gene was cloned and sequenced. The gene contains an open reading frame consisting of 1,161 nucleotides corresponding to 387 amino acid residues. The predicted amino acid sequence displayed 35% and 22% identity with that of the D-threonine aldolase of Arthrobacter sp. DK-38 and Alcaligenes xylosoxidan IFO 12669, respectively. This is the first paper reporting both a purified enzyme with D-3-hydroxyaspartate aldolase activity and also its gene cloning.

Amino Acid Sequence↗
PubMed2003

Two cases of superficial basaloid squamous carcinoma of the esophagus.

. Basaloid squamous carcinoma of the esophagus is very rare. We report two cases of basaloid squamous carcinoma of the esophagus. Both tumors histologically consisted of solid cell nests with intervening fibromyxoid stroma. In some tumor nests were comprised of pseudoglandular structures containing myxoid matrix, and displayed focal immunoreactivity for laminin. Thoracic esophagectomy with lymph node dissection was followed by intrathoracic esophagogastrostomy in both patients. The patients had uneventful postoperative courses. Regular periodic follow-up showed no evidence of recurrence or metastasis in the 22-month postoperative period.

Carcinoma, Squamous Cell↗
PubMed2002

Kondo effect in a quantum antidot.

We report Kondo-like behavior in a quantum antidot (a submicron depleted region in a two-dimensional electron gas) in the quantum-Hall regime. When both spins of the lowest Landau level are present all around the antidot, the resonances between extended edge states via antidot bound states show an abnormal feature in alternate Coulomb-blockaded regions. The feature becomes suppressed when the temperature or source-drain bias is raised as for Kondo resonances in quantum dots. Although the exact mechanism is unknown, Kondo-like correlated tunneling may arise from a Skyrmion-type edge reconstruction. This observation demonstrates the generality of the Kondo phenomenon.

Journal Article↗
PubMed2002

Enzymatic preparation of D-beta-acetylthioisobutyric acid and cetraxate hydrochloride using a stereo- and/or regioselective hydrolase, 3,4-dihydrocoumarin hydrolase from Acinetobacter calcoaceticus.

3,4-Dihydrocoumarin hydrolase (DCH) from Acinetobacter calcoaceticus F46, which was previously found on screening for aromatic lactone-hydrolyzing enzymes, catalyzes the hydrolysis of several linear esters. The substrate specificity of the enzyme toward linear esters was quite characteristic, i.e., (1) it was specific toward methyl esters, (2) it recognized the configuration at the 2-position, and (3) it hydrolyzed diesters to monoesters. DCH hydrolyzed the methyl esters of beta-acetylthioisobutyrate and cetraxate. The products of these reactions were identified as D-beta-acetylthioisobutyrate and cetraxate, respectively, i.e., the hydrolysis reactions catalyzed by DCH were stereo- and/or regioselective. With recombinant Escherichia coli cells expressing the DCH gene as a catalyst, stereospecific hydrolysis of methyl beta-acetylthioisobutyrate and regioselective hydrolysis of methyl cetraxate proceeded efficiently.

Acinetobacter calcoaceticus↗
PubMed2002

Nonspecific interstitial pneumonia as pulmonary involvement of primary Sjögren's syndrome.

The pathologic patterns of lung involvement in nine patients with Sjögren's syndrome (SjS) are evaluated. The patients consisted of three males and six females, with a median age of 59 years. The SjS was diagnosed according to the criteria of the First International Seminar on SjS. In all patients, high-resolution computed radiographic scanning (HRCT) of the lungs was performed, and apparent honeycomb or microhoneycomb formation was observed in six patients. Pathologically, six patients were diagnosed with usual interstitial pneumonia (UIP), and three were diagnosed with nonspecific interstitial pneumonia/fibrosis (NSIP) (group II). There were no apparent honeycomb formations on HRCT in patients diagnosed with NSIP. In conclusion, NSIP is also a possible histologic classification of interstitial pneumonia associated with SjS.

Aged↗
PubMed2002

An assessment of histopathological criteria for infection in joint arthroplasty in rheumatoid synovium.

Intraoperative frozen section is reported to be a reliable means of identifying occult infection for preoperative evaluation of arthroplasty. The aim of this study was to determine whether the reported histopathological criteria--the existence of more than 10 polymorphonuclear cells (PMN) per high-power field--is valuable for determination of infection during the arthroplasty of patients with rheumatoid arthritis (RA). The permanent histological sections of RA synovium were analysed to study the degree of infiltration of PMNs. Furthermore, in order to examine the penetrative distribution of PMNs within the synovial tissues, immunohistochemical staining of PMNs was performed. In addition, the clinical history, from the postoperative period to the present, was investigated in 46 patients (60 joints). The presence of early- and/or late-stage postoperative infection, the development of postoperative fever, the progression of erythrocyte sedimentation rate (ESR) (more than 30 mm per hour) and the changes in CRP (more than 10 mg per litre) were further examined and compared with the histopathological tissue analyses and findings. The results demonstrated the presence of more than five PMNs per high-power field, excluding surface fibrin and inflammatory exudate in at least five separate microscopic fields in 10 joints (16.7%) of nine patients, out of 60 joints of 46 patients, in which no postoperative infection was evident. As to the magnitude of penetrative distribution of PMNs in 10 joints, there was a trend of deepening infiltration among the patients with intensive PMN infiltration. In addition, no development of postoperative fever, CRP or continuous indications of high ESR values were evident in this group. As the existence of more than 10 PMN per high-power field was not absolutely indicative of occult infection, investigation of frozen section during arthroplasty should be carefully managed.

Adult↗