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H Ogihara

Publications and source records attributed to H Ogihara.

At least 37 records · Page 2Linked to original sources
PubMed1999

Peptide transporter in the rat small intestine: ultrastructural localization and the effect of starvation and administration of amino acids.

Peptide transporter-1 is a H+/peptide cotransporter responsible for the uptake of small peptides and peptide-like drugs, and is present in the absorptive epithelial cells of the villi in the small intestine (duodenum, jejunum, and ileum). It has been localized to the apical microvillous plasma membrane of the absorptive epithelial cells of the rat small intestine using the immunogold electron microscopic technique. Digital image analysis of the jejunum revealed that the transporter protein was abundant at the tip of the villus and that the amount decreased from the tip of the villus to its base. The effect of dietary administration of amino acids and starvation on the expression of PepT1 in the jejunum was examined by immunoblotting and image analysis of immunofluorescence. Starvation markedly increased the amount of peptide transporter present, whereas dietary administration of amino acids reduced it. The gradient of the transporter protein along the crypt-villus axis was maintained under either condition. These observations show that it is specific to the microvillous plasma membrane and that its expression is regulated by the nutritional condition.

Amino Acids↗
PubMed1999

Bone turnover and cortical bone mineral density in the distal radius in patients with hyperthyroidism being treated with antithyroid drugs for various periods of time.

OBJECTIVE: Whether patients, who have lost bone mass, can be restored to age-matched control levels by some means is still controversial. We investigated how the thyroid status after antithyroid drug therapy for various periods of time affects bone metabolism in patients with hyperthyroidism by assessing currently used biochemical markers of bone turnover and distal radius bone mineral density (BMD). DESIGN AND PATIENTS: The biochemical markers of bone turnover and BMD at the distal one third of the radius were measured in 79 women with hyperthyroidism treated with antithyroid drugs for various periods of time. The patients were divided into two groups according to thyroid function at the time of study: a hyperthyroid group (serum thyroid stimulating hormone (TSH) < 0.4 mU/l) and an euthyroid group (TSH 0.4-4.0 mU/l). Second, each group was further divided according to the duration of therapy: short-term (less than 3 years) and long-term (3 or more years). MEASUREMENTS: Urinary type I collagen degradation products (CTx) were measured by the CrossLapsTM ELISA kit. Urinary pyridinoline (Pyr) and deoxypyridinoline (Dpyr) were measured by high performance liquid chromatography (HPLC) after acid hydrolysis. Serum N-mid osteocalcin (OCN-mid) was measured by a recently developed enzyme-linked immunosorbent assay. Serum alkaline phosphatase (ALP) was determined by routine laboratory methods. Bone mineral density (BMD) at the distal one third of the radius was measured using dual energy X-ray absorptiometry (DEXA; DCS-600EX, Aloka, Tokyo). RESULTS: There were statistically significant positive correlations of FT3 and FT4 with the biochemical markers of bone turnover. There were significant negative correlations between the biochemical markers and BMD only in patients undergoing long-term therapy. In a comparison between hyperthyroid and euthyroid groups based on duration of treatment (long-term and short-term), and in a comparison without regard for length of treatment (all patients), it was evident that ALP and CTx levels were significantly higher in the hyperthyroid than in the euthyroid groups. Significantly lower BMD Z-scores in the hyperthyroid group compared to those in the euthyroid group were observed only in patients undergoing long-term therapy. CONCLUSIONS: Urinary type I collagen degradation products were a sensitive marker for evaluating the bone turnover in patients with hyperthyroidism. Our data suggested that it might be important to control the levels of TSH within normal ranges during long-term antithyroid drug therapy in order to prevent bone loss.

Adult↗
PubMed1999

Inducible nitric oxide synthase activity by interferon-gamma-producing cells in human radicular cysts.

AIM: In this study, the interaction of interferon-gamma-(IFN-gamma) and inducible nitric oxide synthase (iNOS)-producing cells in human radicular cysts were investigated. METHODOLOGY: Inflamed periapical tissues were obtained from patients at the time of endodontic surgical treatments and were cut into two pieces. After fixing with acetone or 4% paraformaldehyde in phosphate-buffered saline, 5-m-thick paraffin and cryostat sections were prepared. The paraffin sections of the inflamed tissues were evaluated histologically with haematoxylineosin stains. The specimens diagnosed as radicular cysts were then examined by immunostaining. Immunohistochemistry for iNOS and fluoresence microscopy for IFN-gamma using the cryostat sections were performed with a mixture of affinity purified human iNOS antiserum and human IFN-gamma monoclonal antibodies. RESULTS: The results revealed that iNOS-gamma producing cells localized adjacent to IFN-gamma-producing cells. In addition, some of iNOS-producing cells exhibited immunoreactive IFN-gamma. On the other hand, epithelial cells showed significant levels of iNOS production, but not IFN-gamma. CONCLUSIONS: The data would suggest the possibility that iNOS production could be precisely controlled by autocrine or paracrine effects of IFN-gamma producing cells in radicular cysts and might play a pivotal role in periapical lesions. These findings are consistent with a hypothesis suggesting that NO inhibitors could be used through the root canals as a pharmacological treatment for periapical lesions.

Adult↗
PubMed1999

Expression profile of active genes in mouse lymph node high endothelial cells.

High endothelial venules (HEV) allow rapid and selective lymphocyte trafficking from the blood into secondary lymphoid tissues. Here we report the expression profile of active genes in mouse high endothelial cells (HEC). HEC were first purified from mouse lymph nodes (LN) by magnetic cell sorting with MECA-79 mAb and a 3'-directed cDNA library that faithfully represents the composition of mRNA was constructed. A total of 1495 cDNA sequences were obtained from randomly selected clones. Based on their sequence identity, they were grouped into 754 different species [gene signatures (GS)] of which 335 GS were identified in GenBank. Among the previously identified genes, expression of several endothelial cell surface molecules including endoglin and ICAM-1 was detected in HEC. Comparison of the gene expression profile with that of purified CD31(+) flat endothelial cells identified several molecules, such as KC chemokine and Duffy antigen/receptor for chemokines, that are known to be selectively expressed in activated endothelial cells or post-capillary venules. Interestingly, mac25/TAF, which is known to be expressed specifically in tumor vessels and implicated in the regulation of cell adhesion, was highly and selectively expressed in HEC in mouse LN, suggesting that it may participate in regulating HEC-specific functions. Comparison with the expression profiles obtained from 35 different cell types showed at least 22 GS that were apparently specific to HEC. Our results illustrate the expression differences between HEC and CD31(+) flat endothelial cells, and will be useful for the identification and characterization of genes specific for HEC.

Animals↗
PubMed1999

Raised concentrations of aldehyde lipid peroxidation products in premature infants with chronic lung disease.

AIM: To indicate the extent of lipid peroxidation induced by oxidative stress, by measuring aldehyde end products in biological samples. METHODS: A highly specific gas chromatography and mass spectrometry (GC/MS) method was used to measure plasma concentrations of aliphatic aldehydes within the first week of life in 13 premature infants who subsequently developed chronic lung disease (CLD) and 11 infants without CLD (non-CLD). The oxime-tert-butyldimethylsilyl derivatives of aldehydes were analysed using 2,2,6,6-d4-cyclohexanone as the internal standard. RESULTS: All of the aldehydes measured were raised in those infants with CLD compared with non-CLD infants. Plasma concentrations of heptanal, 2-nonenal, and 4-hydroxynonenal (HNE) were significantly increased in CLD infants on the day of birth, while the differences in all aldehydes between the two groups were not significant at 4-6 days of age. Logistic regression analysis showed that the increase in these three aldehydes within the first 24 hours of life independently showed significant associations with the development of CLD. In particular, an HNE concentration of > or = 200 nM on day 0 was the best predictor for the early detection of CLD (odds ratio = 32.0), followed by a 2-nonenal concentration of > or = 150 nM (odds ratio = 16.0). CONCLUSIONS: These findings suggest that lipid peroxidation may have a role in the pathogenesis of neonatal CLD.

Aldehydes↗
PubMed1999

[Allantoin].

Explore the source record for details and available documents.

Adolescent↗
PubMed1998

Transcriptional regulation of osteopontin gene in vivo by PEBP2alphaA/CBFA1 and ETS1 in the skeletal tissues.

Osteopontin (Opn) and polyoma enhancer-binding protein (PEBP) 2alphaA/core binding factor (CBFA) 1 have been suggested to play important roles in ossification. The overlapping localization of opn and PEBP2alphaA/CBFA1 mRNA, and the marked decrease of opn mRNA expression in PEBP2alphaA knockout mice, indicated that the transcription of opn gene was controlled by PEBP2alphaA. In the present study, we determined the direct regulation of PEBP2alphaA on the opn promoter activity. Opn promoter activity was markedly enhanced by PEBP2alphaA and ETS1 in a synergistic manner. The synergistic effect was diminished when either the PEBP2alphaA or ETS1 binding site was mutated, or the spatial arrangement of these sites was mutated by a 4-nt insertion. The distance between these sites was important for transactivation but not protein-DNA binding. The direct interaction between PEBP2alphaA and ETS1 was depended on protein-DNA binding. These results suggested that the specific spatial arrangement of both sites and direct interaction between PEBP2alphaA and ETS1, were essential for promoter function. Furthermore, endogenous opn mRNA was decreased with the introduction of dominant negative PEBP2alphaA to MC3T3/E1 cells expressing endogenous PEBP2alphaA, ETS1 and opn. These findings suggest that PEBP2alphaA and ETS1 cooperate in vivo to regulate expression of the opn gene in the skeletal tissue. Cell type-specific regulation of Opn gene expression will also be discussed.

3T3 Cells↗
PubMed1998

Impaired expression of integrin alpha-4 subunit in cultured mast cells derived from mutant mice of mi/mi genotype.

The mi locus encodes a member of the basic-helix-loop-helix-leucine zipper protein family of transcription factors (hereafter called MITF). We have reported that expression of several genes was impaired in cultured mast cells (CMCs) of mi/mi mice due to a defective transactivation ability of mutant MITF (mi-MITF). Because attachment of mi/mi CMCs to fibroblasts is impaired, we examined the expression of integrin genes in mi/mi CMCs in the present study. Among the integrin genes examined, the expression of integrin alpha4 subunit was barely detectable in mi/mi CMCs, and the alpha4 protein was not detected by flow cytometry either. The specific adhesion to vascular cell adhesion molecule-1 (VCAM-1), the ligand for alpha4 subunit, was observed in +/+ CMCs but not in mi/mi CMCs, indicating that the expression of integrin alpha4 subunit at a functional level did not occur in mi/mi CMCs. In the promoter region of the alpha4 subunit gene, there was a CACTTG motif to which normal MITF (+- MITF) bound. The coexpression of +-MITF but not of mi-MITF transactivated the promoter of the alpha4 subunit gene. The deletion or mutation of the CACTTG motif abolished the transactivation by +-MITF, suggesting that +-MITF directly transactivated the gene encoding alpha4 subunit of integrin.

Animals↗
PubMed1998

Systematic method to obtain novel genes that are regulated by mi transcription factor: impaired expression of granzyme B and tryptophan hydroxylase in mi/mi cultured mast cells.

The mi locus encodes a member of the basic-helix-loop-helix-leucine zipper protein family of transcription factors (hereafter called MITF). We have reported that the expression of several genes was impaired in cultured mast cells (CMCs) of mi/mi genotype, and demonstrated the involvement of MITF in the transcription of these genes. To obtain new genes whose transcription may be regulated by MITF, we prepared a subtracted cDNA library using +/+ and mi/mi CMCs. We found two clones carrying the granzyme (Gr) B and tryptophan hydroxylase (TPH) cDNAs in the subtracted library. The expression of the Gr B and TPH genes decreased in mi/mi CMCs, and recovered to nearly normal level by the overexpression of normal (+) MITF but not of mutant (mi) MITF. The +-MITF bound three and one CANNTG motifs in the Gr B and TPH promoters, respectively, and transactivated these two genes, indicating the involvement of +-MITF in their expression. Because TPH is the rate-limiting enzyme for serotonin synthesis, we examined the serotonin content of +/+ and mi/mi CMCs. The serotonin content was significantly smaller in mi/mi CMCs than in +/+ CMCs. The introduction of +-MITF but not of mi-MITF normalized the serotonin content in mi/mi CMCs.

Animals↗
PubMed1998

Oxidation products of uric acid and ascorbic acid in preterm infants with chronic lung disease.

Allantoin, the oxidation product of uric acid (UA), can be used as an in vivo marker of free radical generation. The aims of the present study were to evaluate the allantoin changes in plasma and bronchoalveolar lavage fluid (BALF) as well as to examine plasma levels of ascorbic acid (AA) and its oxidation product, dehydroascorbic acid (DHAA), in infants with or without chronic lung disease (CLD) during the first week of life. The study population was 20 infants of 24-30 weeks gestation, comprising 10 who subsequently developed CLD and 10 without CLD. In the CLD infants, the plasma allantoin/UA ratio showed a significant increase after day 1 and continued to increase gradually to reach a peak on day 6 (6.5 +/- 4.1% for CLD and 2.1 +/- 0.9% for non-CLD infants). The allantoin/UA ratio in BALF was also higher in CLD infants and the difference reached significance on days 4-6 (41.2 +/- 15.8% for CLD and 11.7 +/- 9.9% for non-CLD infants). In contrast to allantoin, the plasma DHAA/AA ratio did not differ between the 2 groups throughout the study period. Our findings that the allantoin/UA ratios were significantly higher in CLD than non-CLD infants not only in plasma but also in BALF, and that the intergroup differences of this ratio in both plasma and BALF was more prominent in the latter half of the first week of life further confirm our previous speculation that oxygen radicals are involved in the development of neonatal CLD.

Allantoin↗
PubMed1997

Abnormal expression of mouse mast cell protease 5 gene in cultured mast cells derived from mutant mi/mi mice.

Mast cells contain a lot of mast cell-specific proteases. We have reported that the expression of mouse mast cell protease 6 (MMCP-6) is remarkably reduced in both cultured mast cells (CMCs) and skin mast cells of mi/mi mutant mice. In the present study, we found that the expression of MMCP-5 was reduced in CMCs but not in skin mast cells of mi/mi mice, and we compared the regulation mechanisms of MMCP-5 with those of MMCP-6. The mi locus encodes a member of the basic-helix-loop-helix-leucine zipper (bHLH-Zip) protein family of transcription factors (hereafter called MITF). The consensus sequence recognized and bound by bHLH-Zip transcription factors is CANNTG. The overexpression of the normal (+) MITF but not of mi-MITF normalized the poor expression of the MMCP-5 gene in mi/mi CMCs, indicating the involvement of +-MITF in transactivation of the MMCP-5 gene. Although +-MITF directly bound CANNTG motifs in the promoter region of the MMCP-6 gene and transactivated it, the binding of +-MITF to the CAGTTG motif in the promoter region of the MMCP-5 gene was not detectable. The +-MITF appeared to regulate the transactivation of the MMCP-5 gene indirectly. Moreover, addition of stem cell factor to the medium normalized the expression of the MMCP-5 but not of the MMCP-6 gene in mi/mi CMCs. Despite the significant reduction of both MMCP-5 and MMCP-6 expressions in mi/mi CMCs, their regulation mechanisms appeared to be different.

Animals↗
PubMed1997

[Recent trends in incidence of respiratory tract pathogens and antimicrobial susceptibilities of Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis isolated in 1994 and 1995].

The incidence of pathogenic bacteria in respiratory tract infections in 1994 and 1995 was investigated using quantitative cultures of sputa from patients with the infections in our department. Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis were isolated at high rates (70.5% in 1994 and 73.8% in 1995) from the specimens of out-patients, and the incident rates were similar to the past data. The antimicrobial susceptibilities of these three pathogens were examined with the agar dilution method. The incidence of penicillin (Pc) resistant S. pneumoniae against which MIC of Pc-G was higher than 0.125 microgram/ml was markedly increased from 24% in 1994 to 34.9% in 1995. Most of the Pc resistant isolates were also resistant to other antibiotics including erythromycin, minocycline and tosufloxacin. Serotype of strains against which MIC of Pc-G was higher than 1.0 microgram/ml was 19. The ratios of beta-lactamase-producing strains among H. influenzae isolated in 1994 and 1995 were 20 and 15.8%, respectively, which were slightly higher than those in the past. One quinolone resistant strain was isolated in this study. Although the ratio of beta-lactamase-producing strains among M. catarrhalis was as high (96.7%) as in the past, no increased resistance against the drugs examined was observed.

Anti-Bacterial Agents↗
PubMed1996

Immuno-localization of H+/peptide cotransporter in rat digestive tract.

In the mammalian digestive tract, small peptides are absorbed by a H+-coupled peptide transport system. Using an antibody against the rat H+/peptide cotransporter (PepT1), we examined the localization of PepT1 immunohistochemically along the rat digestive tract. PepT1 was detected in the small intestine (duodenum, jejunum, and ileum), but not in the esophagus, stomach, colon, or rectum. PepT1 was especially enriched in the villi, where it was localized in the brush border of the absorptive epithelial cells. PepT1 was not detected in the mucus-secreting goblet cells or less-differentiated epithelial cells in the crypts. These observations show that PepT1 is specific to the brush border of the differentiated absorptive epithelial cells and suggest that H+-coupled uptake of small peptides and peptide-like drugs occurs at the apical membrane of these cells in the small intestine.

Animals↗
PubMed1996

Effect of physical activity as a caddie on ultrasound measurements of the Os calcis: a cross-sectional comparison.

This cross-sectional study investigated the effect of long-term activity as a caddie on ultrasonic properties of the os calcis. We measured 74 healthy women, age 20-59 years, who worked at a golf course as caddies. An age-matched control group of 433 healthy women, who were office workers or housewives, also were recruited for comparison. The ultrasound measurements were performed with an Achilles ultrasound densitometer. The quadriceps muscle strength and the hand grip strength were measured in a perimenopausal subgroup (45-59 years) of the caddies and a subgroup of controls matched for age, height, weight, and body mass index. Urinary pyridinoline and deoxypyridinoline were also measured in these perimenopausal subgroups. Caddies had significantly higher ultrasound values than controls in the 40-49 (stiffness index, 101.6 +/- 12.9% versus 87.9 +/- 11.9%; p < 0.0001) and 50-59 (stiffness index, 90.5 +/- 11.6% versus 77.2 +/- 11.6%; p < 0.0001) age-stratified groups. Quadriceps strength and grip strength were significantly higher in caddies than those in controls. In postmenopausal caddies, all ultrasound values were significantly higher than for controls. In caddies there were not significant decreases of any ultrasound values with postmenopausal age. Even for the subgroup within 3 years of menopause there were significant differences between caddies and controls (p < 0.01). There were no significant increases of pyridinoline and deoxypyridinoline after menopause in the caddies. We demonstrated that the caddies had higher ultrasound properties of the os calcis and lower bone resorption after menopause compared with controls.

Adult↗
PubMed1996

New evidence for the involvement of oxygen radicals in triggering neonatal chronic lung disease.

We measured the plasma concentration of allantoin, an oxidation product of uric acid and an "in vivo" marker of free radical generation, within 24-48 h after birth in 10 premature infants who subsequently developed chronic lung disease (CLD) and 9 infants without CLD (non-CLD). The plasma allantoin level (mean +/- SD, 25.9 +/- 9.8 microM for CLD versus 11.0 +/- 5.7 microM for non-CLD, p < 0.01) and the allantoin/urate ratio (5.8 +/- 2.0% for CLD infants versus 2.4 +/- 0.9% for non-CLD infants, p < 0.01) were significantly higher in the CLD group than those in the non-CLD group. These observations suggest the possible involvement of oxygen radicals in triggering CLD. In addition, the plasma allantoin concentration and the allantoin/urate ratio may be useful early predictors of the development of CLD.

Allantoin↗
PubMed1996

The incidence of respiratory tract pathogens and antimicrobial susceptibilities of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella (Branhamella) catarrhalis isolated between 1990 and 1993.

Using a quantitative culture of sputum, the incidence of pathogenic bacteria in respiratory infection in our laboratory between 1990 and 1993 were investigated. While Haemophilus influenzae, Streptococcus pneumoniae and Moraxella (Branhamella) catarrhalis were isolated at high rates (67-78%) from the specimens of outpatients throughout the study period, the incidence of S pneumoniae has increased gradually. The antimicrobial susceptibilities of these three pathogens were examined with the agar dilution method. A marked increase of penicillin (PC) resistant S. pneumoniae (MIC > or = 0.1 microgram/ml) was observed with a resistance rate of 2.1% in 1990 and 25% in 1993. Resistance to erythromycin (EM, MIC > or = 1.56 micrograms/ml) was 8.5% in 1990 but then increased to 34% in 1992. Most of the PC resistant isolates were resistant to multidrugs such as EM, minocycline and clindamycin. The MICs of all beta-lactams examined for S. pneumoniae increased along with the MICs of PC, though the level varied between drugs. The rates of beta-lactamase positive H. influenzae gradually decreased, being 14.3% in 1990 and 7.4% in 1993, whereas those of M. (B) catarrhalis were consistently high (> 90%) every year. In addition to beta-lactamase production, the emergence of strains of H. influenzae and M. (B) catarrhalis resistant to new quinolone drugs should be noted.

Drug Resistance, Microbial↗
PubMed1995

Plasma copper and antioxidant status in Wilson's disease.

It has been demonstrated that the level of serum copper unbound to ceruloplasmin (loosely bound copper) is increased in Wilson's disease, although the total serum copper concentration is usually low, reflecting a low ceruloplasmin level. To assess the contribution of free radical reactions catalyzed by nonceruloplasmin copper to the development of complications in this disease, we investigated copper and antioxidant status in four untreated patients who had hepatic dysfunction with or without hemolytic anemia and made a comparison with five patients controlled on penicillamine therapy and 19 age-matched healthy children. We found that loosely bound copper in plasma measured by the phenanthroline assay was detectable in three of four untreated patients with Wilson's disease, but was not detectable in the patients during therapy or in the healthy controls. Among the various antioxidants, the ascorbate and urate levels were markedly reduced before treatment (mean +/- SD, 23 +/- 16 microM for ascorbate and 90 +/- 59 microM for urate) compared with the values in the patients during treatment with penicillamine (67 +/- 19 and 302 +/- 78 microM, p < 0.05) and in control children (60 +/- 8 and 254 +/- 48 microM, p < 0.05). We also demonstrated that the plasma concentration of allantoin, an oxidation product of uric acid and a possible marker of radical generation in vivo, was markedly elevated in the untreated patients (11.0 +/- 1.8 versus 4.3 +/- 0.5 microM in patients on therapy and 6.5 +/- 0.8 microM in controls, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Allantoin↗