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H Okuda

Publications and source records attributed to H Okuda.

At least 91 records · Page 5Linked to original sources
PubMed1999

Measurement of serum levels of des-gamma-carboxy prothrombin in patients with hepatocellular carcinoma by a revised enzyme immunoassay kit with increased sensitivity.

BACKGROUND: Des-gamma-carboxy prothrombin (DCP) is a useful tumor marker for hepatocellular carcinoma (HCC). The conventional enzyme immunoassay (EIA) kit for DCP lacks adequate sensitivity to detect small HCC. Thus, a revised EIA kit for DCP has been developed. In this revised DCP kit, the blank value has been reduced, making it now possible to obtain a normal value. The authors used this revised EIA kit for DCP with increased sensitivity and evaluated its usefulness as a tumor marker for HCC. METHODS: Serum DCP and alpha-fetoprotein (AFP) levels were determined in 60 patients with HCC, 60 with cirrhosis, 57 with chronic hepatitis, and 273 normal subjects. The cutoff value for the revised DCP kit was determined to be 40 mAU/mL, and the values for the conventional DCP kit and AFP were 100 mAU/mL (0.1 AU/mL) and 20 ng/mL, respectively. RESULTS: The mean DCP value was 17.5 mAU/mL in the normal subjects, and the detection limit was 10 mAU/mL for this revised DCP kit. The positivity rate for DCP in patients with HCC was 60% by the revised DCP kit, in contrast to 40% by the conventional DCP kit. The sensitivity, specificity, and accuracy of the revised kit were 60%, 92.3%, and 81.4%, respectively, whereas those of the conventional kit were 40%, 98.3%, and 78.5%. Thirty-five percent of HCC tumors smaller than 2 cm and 78.1% of those larger than 3 cm were positive for DCP by the revised kit. The corresponding figures were 20% and 56.3% with the conventional kit. Twelve (33.3%) of the 36 HCC patients who were negative for DCP by the conventional kit were positive by the revised kit. When the revised DCP kit was used in combination with AFP, 86.7% of the HCC patients and 78.3% of the patients with solitary HCC were positive for at least 1 of these markers. CONCLUSIONS: The revised DCP kit is more useful than the conventional DCP kit as a tumor marker for HCC and should be used in combination with AFP.

Adult↗
PubMed1999

The genomic organization of the partial D category DVa: the presence of a new partial D associated with the DVa phenotype.

Within the Rh blood group, the partial D phenotype is a well known RhD variant, that induces Rh-incompatible blood transfusion and hemolytic diseases in the newborn. The partial D category DVa phenotype (DVa Kou.) results from a hybrid of RhD-CE-D transcript. We demonstrated a genomic organization of the hybrid RHD-CE-D gene leading to the DVa phenotype, and showed that the DVa gene were generated from gene conversion between the RHD and the RHCE genes in relatively small regions. This study also revealed that the presence of a new partial D associated with the DVa phenotype, which we termed the DVa-like phenotype. In this phenotype, five RHD-specific nucleotides were replaced with the corresponding RHCE-derived nucleotides on the exon 5 of the RHD gene. In addition, two variants of the mutated RHD genes at nucleotide 697 were revealed in the RhD variant samples. These results will provide useful information for future research into the diversification of the Rh polypeptides.

Alleles↗
PubMed1999

Cervical adenocarcinoma, a novel combination chemotherapy with mitomycin C, etoposide, and cisplatin for advanced or recurrent disease.

We review the cases of 31 patients with stage IVb or recurrent cervical adenocarcinoma who were treated with combination chemotherapy utilizing mitomycin C, etoposide, and cisplatin (MEP). The total response rate was 16.1% (95% confidence intervals (CIs), 5. 5 to 33.7%) with 4 patients having a complete response (CR) and 1 having a partial response. In patients with no prior chemotherapy, the response rate was 26.7% (95% CIs, 7.8 to 55.1%) with 2 of these CR patients surviving over 3 years, 1 a disease-free survival. A marked response was found in distant recurrent lesions. The major toxicity was myelosuppression. Forty-five percent of patients had leukocytopenia above grade 3; thrombocytopenia and anemia were not common. In patients with cervical adenocarcinoma and no prior chemotherapy, there was a moderate response to MEP therapy.

Adenocarcinoma↗
PubMed1999

Inhibitory effect of arginine-derivatives from ginseng extract and basic amino acids on protein-arginine N-methyltransferase.

Protein-arginine N-methyltransferase (protein methylase I) catalyzes methylation of arginyl residues on substrate protein posttranslationally utilizing S-adenosyl-L-methionine as the methyl donor and yields NG-methylarginine residues. Arginyl-fructose and arginyl-fructosyl-glucose from Korean red ginseng were found to inhibit protein methylase I activity in vitro. This inhibitory activity was shown to be due to arginyl moiety in the molecules, rather than that of carbohydrates. Several basic amino acids as well as polyamines were also found to inhibit protein methylase I activity. Interestingly, the intensity of the inhibitory activity was correlated with the number of amino-group in polyamines, thus, in the order of spermine > spermidine > putrescine > agmatine-sulfate, with IC50 at approximately 15 mM, 25 mM, 35 mM, and 50 mM, respectively. On the other hand, neutral amino acids or NaCl did not inhibit the enzyme activity. Lineweaver-Burk plot analysis of the protein methylase I activity in the presence of arginine and spermidine indicated that the inhibition was competitive in nature in respect to protein substrate, with the Ki values of 24.8 mM and 11.5 mM, respectively.

Amino Acids↗
PubMed1999

The STR polymorphisms in intron 8 may provide information about the molecular evolution of RH haplotypes.

We identified simple-sequence repeat polymorphisms in intron 8 of the RHD and RHCE genes, both of which contained the 5-bp repeat unit (AAAAT)n. We analyzed the polymorphisms of this short tandem repeat (STR) in 104 Japanese RhD-positive and 124 RhD-negative (87 RHD gene negative and 37 nonfunctional RHD gene positive) donors by the polymerase chain reaction (PCR) and subsequent typing by electrophoresis and silver staining. We found five alleles (10, 11, 12, 13, and 14 repeats) in the RHD gene and four (7, 8, 9, and 10 repeats) in the RHCE gene. The Rh phenotypes were closely associated with polymorphisms of the STR. The Ce allele had 12 repeats in the RHD gene and 9 repeats in the RHCE gene at high frequency. The cE allele frequently had 10-12 repeats in the RHD gene and 10 repeats in the RHCE gene. The 10 repeats in the RHCE gene were identified exclusively in the 87 RHD gene-negative donors and 9 repeats were identified only in those with the RhC antigen. These results indicate that both haplotypes of dce and dcE arose from single RHD gene deletion and recombination events, respectively. In the 37 RhD-negative donors with a nonfunctional RHD gene, 12 repeats in the RHD gene and 9 repeats in the RHCE gene were frequently observed. Thus, the RhD-negative with a nonfunctional RHD gene combination might have arisen from the DCe haplotype via a mutation that abolished RHD gene expression. These findings suggest that the STR polymorphisms might shed light upon the molecular evolution of RH haplotypes.

Alleles↗
PubMed1999

Screening of lipase inhibitors from marine algae.

The possible presence of an inhibitor of pancreatic lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) was screened in 54 marine algae. An active inhibitor, caulerpenyne, was purified from an extract of Caulerpa taxifolia, using ethyl acetate extraction, followed by successive chromatographies on ODS and silica gel columns. The purified inhibitor was identified by thin-layer chromatography, infrared and nuclear magnetic resonance spectroscopy. Caulerpenyne competitively inhibited lipase activities using emulsified triolein and dispersed 4-methylumbelliferyl oleate (4-MU oleate) as substrates. The concentrations producing 50% inhibition against triolein and 4-MU oleate hydrolysis were 2 mM and 13 microM, respectively. In vivo, oral administration of corn oil with or without caulerpenyne to rats demonstrated a reduced and delayed peak plasma triacylglycerol concentration with caulerpenyne.

Administration, Oral↗
PubMed1999

Wax ester-synthesizing activity of lipases.

The synthesis/hydrolysis of wax esters was studied in an aqueous solution using purified rat pancreatic lipase, porcine pancreatic carboxylester lipase, and Pseudomonas fluorescens lipase. The equilibrium between wax ester synthesis and hydrolysis favored ester formation at neutral pH. The synthesizing activities were measured using free fatty acid or triacylglycerol as the acyl donor and an equimolar amount of long-chain alcohol as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with these lipases, wax ester was synthesized, in a dose- and time-dependent manner, and the apparent equilibrium ratio of palmityl oleate/free oleic acid was about 0.9/0.1. These lipases catalyzed the hydrolysis of palmityl oleate emulsified with gum arabic, and the apparent equilibrium ratio of palmityl oleate/free oleic acid was also about 0.9/0.1. The apparent equilibrium ratio of wax ester/free fatty acid catalyzed by lipase depended on incubation pH and fatty alcohol chain length. When equimolar amounts of trioleoylglycerol and fatty acyl alcohol were incubated with pancreatic lipase, carboxylester lipase, or P. fluorescens lipase, wax esters were synthesized dose-dependently. These results suggest that lipases can catalyze the synthesis of wax esters from free fatty acids or through degradation of triacylglycerol in an aqueous medium.

Adenosine Triphosphate↗
PubMed1999

Normative reproductive indices for male and female adult Sprague-Dawley rats.

The Sprague-Dawley rat is traditionally used as the experimental model for the study of contraceptive agents and reproductive toxicants. Until recently, the normative values used to compare hormone levels after drug exposure were based on the values generated by radioimmunoassay methods developed 30 years ago. To ascertain normative reproductive indices for adult female and male Sprague-Dawley rats over a 6-month age period, we measured luteinizing hormone, testosterone, and estradiol using commercially available kits that employ updated assay techniques. In addition, sperm indices were correlated with reproductive hormones over the same time period. Animals were killed at 107, 128, 156, 212, and 268 days of age irrespective (for females) of cycle stage. Serum LH levels did not change with increasing age; however, the female rats had significantly higher LH values than did the males at comparable ages (p < 0.001). Testosterone levels and sperm parameters did not significantly change with increasing age. Estradiol levels were significantly higher in 107-day-old female rats than they were in female rats in all older age groups (p < 0.01). The values reported can be used in designing and interpreting data generated in ongoing, long term toxicological and contraceptive studies using the rat animal model.

Animals↗
PubMed1999

Serum C-reactive protein as a prognostic factor in patients with epithelial ovarian cancer.

OBJECTIVE: It is well known that the serum level of Interleukin-6 (IL-6) correlates with the level of C-reactive protein (CRP). The purpose of this study is to determine the significance of CRP as a prognostic factor in epithelial ovarian cancer. STUDY DESIGN: The present study is comprised of 120 patients with epithelial ovarian cancer from 1985 to 1992. In this study, CRP levels above 50 mg/l were considered high CRP. Univariate and multivariate analyses were performed to identify clinicopathological variables associated with poor survival. RESULTS: The serum CRP value was significantly associated with the volume of ascites (P = 0.000004). Univariate analysis showed that the FIGO stage, primary tumour diameter, size of residual tumour, histologic grade, volume of ascites and high serum level of CRP were significant prognostic factors. Cox's multivariate proportional hazard model showed that histologic grade was the most important prognostic factor (P = 0.0026). FIGO stage and volume of ascites were also independent factors for 5-year survival (P = 0.0310 and P = 0.0216, respectively). However, the serum CRP value was not an independent prognostic factor. CONCLUSION: CRP is an adverse prognostic factor in univariate analysis, but not in multivariate analysis.

Adenocarcinoma, Clear Cell↗
PubMed1999

Vascular endothelial growth factor is implicated in early invasion in cervical cancer.

The association between the expression of vascular endothelial growth factor (VEGF) and clinicopathological factors has scarcely been examined in cervical cancer. This study examines the level of VEGF messenger RNA (mRNA) expression in invasive cervical cancer and its association with clinicopathological features including microvessel density. The level of VEGF mRNA was assessed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) using beta-actin as an internal control in 66 patients with stages Ia-IVb invasive cervical cancer. In 42 patients who underwent surgery, the microvessel count was also assessed by immunostaining for factor VIII-related antigen in the most neovascularised area of the specimen. The highest level of VEGF mRNA expression was observed in early invasive cervical cancers. Except for stage IVb, the stage of the disease inversely correlated with the level of VEGF mRNA (P < 0.05). There was no significant difference in the level of VEGF mRNA with respect to histological cell types. 38 patients with stages Ib-IIb cervical cancer underwent radical hysterectomy and pelvic lymphadenectomy. There was no significant difference in the level of VEGF mRNA with respect to lymph node metastasis, depth of stromal invasion, tumour size, parametrial involvement or vaginal involvement among these patients. A significant relationship was found between the microvessel density and the level of VEGF mRNA (P < 0.01). These findings provide evidence that the expression of VEGF is involved in the promotion of angiogenesis in cervical cancer and plays an important role in early invasion.

Endothelial Growth Factors↗
PubMed1999

Transient cyclophosphamide treatment before intraportal readministration of an adenoviral vector can induce re-expression of the original gene construct in rat liver.

Although adenovirus is an attractive vehicle for transferring therapeutic genes in vivo, animal studies have indicated that the clinical usefulness of adenoviruses may be limited by their immunogenicity. Although immunosuppressive strategies around the time of initial exposure of adenoviruses have been shown to prevent the formation of neutralizing antibodies and permit the successful readministration of adenoviruses in animals, the practicality of the approaches remains questionable. Because the majority of prospective gene therapy patients have already been infected with wild-type adenoviruses, initial treatment with adenoviruses in humans may correspond to readministration of adenoviruses into animals. It is shown here that although intraportal infusion of adenoviruses carrying a reporter lacZ gene resulted in transient high levels of transgene expression in the rat liver, intraportal readministration of adenoviruses failed to induce detectable levels of transgene expression. Conversely, when animals were treated transiently with cyclophosphamide before the intraportal readministration of adenoviruses, development of neutralizing antibodies and antigen-specific T cell proliferation in response to adenoviral readministration was significantly suppressed and successful re-expression of the transgene was achievable. These results may have important implications for efficacy considerations when adenoviral vectors are employed in clinical settings.

Adenoviridae↗
PubMed1999

Anti-obesity action of oolong tea.

OBJECTIVE: Oolong tea is traditionally reported to have anti-obesity and hypolipidaemic effects. The present study was performed to clarify whether oolong tea prevented obesity induced in mice by the oral administration of a high-fat diet for 10 weeks. DESIGN: High-fat diet-induced obese mice were treated with oolong tea for 10 weeks. The effects of various active fractions isolated from oolong tea on noradrenaline-induced lipolysis were examined with isolated fat cells and a cell-free system consisting of lipid droplets and hormone-sensitive lipase (HSL). RESULTS: The mean food consumption was not significantly different between high-fat diet-treated mice and high-fat plus oolong tea diet-treated mice. Oolong tea prevented the obesity and fatty liver induced by a high-fat diet. A water extract of oolong tea enhanced noradrenaline-induced lipolysis, and the active substance was identified as caffeine. Caffeine enhanced noradrenaline-induced lipolysis in fat cells without a concomitant increase in HSL activity and also accelerated the hormone-induced lipolysis in a cell-free system consisting of lipid droplets and HSL, but not in the cell-free system with sonicated lipid droplets and HSL. Oolong tea extract inhibited pancreatic lipase activity. CONCLUSION: It was demonstrated that the anti-obesity effects of oolong tea in high-fat diet-treated mice might be due partly to the enhancing effect of caffeine isolated from oolong tea on noradrenaline-induced lipolysis in adipose tissue, and to the inhibitory action of some other substance in oolong tea on pancreatic lipase activity. Caffeine was found to enhance lipolysis through acting on lipid droplets but not on HSL. The results suggest that oolong tea may be an effective crude drug for the treatment of obesity and fatty liver caused by a high-fat diet.

Adipocytes↗
PubMed1999

Reduction in fat storage during chitin-chitosan treatment in mice fed a high-fat diet.

OBJECTIVE: Chitin and chitosan are polymers containing more than 5000 acetylglucosamine and glucosamine units, respectively, and their molecular weights are over one million Daltons. The present study assessed the effects of chitin-chitosan on the activity of pancreatic lipase in vitro and on the degree of fat storage induced in mice by the oral administration of a high-fat diet for nine weeks. DESIGN: Mice were fed a high-fat diet and treated with chitin-chitosan for nine weeks. Experiments were also carried out to clarify whether or not chitin-chitosan inhibited pancreatic lipase activity in assay systems using triolein emulsified with lecithin, gum arabic or Triton X-100. RESULTS: Chitin-chitosan prevented the increase of body weight, hyperlipidaemia and fatty liver induced by a high-fat diet. Chitin-chitosan inhibited hydrolysis of triolein, emulsified with phosphatidylcholine, but not that of triolein emulsified with gum arabic and Triton X-100. These results suggest that the site of inhibitory action of chitin-chitosan may not be the enzyme but its substrate. CONCLUSION: The anti-obesity effects of chitin-chitosan in high-fat diet-treated mice might be partly due to the inhibition of intestinal absorption of dietary fat. Consequently, chitin-chitosan might cause improvement of the fatty liver and hyperlipidaemia in mice fed a high fat diet through inhibiting intestinal absorption of dietary fat.

Adipose Tissue↗
PubMed1999

Metabolic characteristics of the elderly with recurrent calcium oxalate stones.

OBJECTIVE: To determine the metabolic characteristics of elderly patients with recurrent calcium oxalate stones. PATIENTS AND METHODS: Metabolic abnormalities were investigated in 88 patients with recurrent calcium oxalate stones, including 70 aged <60 years and 18 aged >/=60 years. The frequency of each metabolic abnormality and the value of each urinary constituent were compared among subgroups of age and gender. RESULTS: Hyperoxaluria was the most common abnormality, present in 56% and 67% of patients aged <60 and >/=60 years, respectively. Hyperuricosuria was significantly more common in older than in younger patients. There were no significant differences in the frequencies of hypercalciuria and hypocitraturia between the age groups. The urinary excretion of oxalate and the ratio of oxalate to creatinine were significantly greater in older than in younger men. The frequency of low urine volume was lower in older than in younger patients and the mean urinary volume was also greater in the older group. CONCLUSIONS: Hyperuricosuria and hyperoxaluria seem to be essential risk factors for calcium oxalate stone formation in elderly patients. Urinary oxalate excretion is significantly greater in older than in younger stone formers and is more prominent in men.

Adult↗
PubMed1999

Relationship between hormone-sensitive lipolysis and lipase activity in rat fat cells.

An assay for total hormone-sensitive lipase (HSL) in rat fat cells was devised in which fat-associated HSL was solubilized with ether, and triolein or cholesteryloleate was used as substrate. Norepinephrine (NE) caused marked release of glycerol from fat cells but did not activate HSL as estimated using triolein or cholesteryloleate as substrate. Propranolol, a beta-blocker, inhibited NE-induced lipolysis in fat cells without a concomitant reduction in HSL activity. The antilipolytic action of insulin on NE-induced lipolysis could not be explained by a decrease in HSL activity. Neither ACTH-induced lipolysis in fat cells nor its inhibition by insulin was accompanied by matching fluctuations in HSL activity. These results indicate that neither NE and ACTH-induced lipolysis in fat cells, nor the antilipolytic actions of propranolol and insulin, involve fluctuations in HSL activity.

Adipocytes↗
PubMed1999

Fatty acid alcohol ester-synthesizing activity of lipoprotein lipase.

The fatty acid alcohol ester-synthesizing activity of lipoprotein lipase (LPL) was characterized using bovine milk LPL. Synthesizing activities were determined in an aqueous medium using oleic acid or trioleylglycerol as the acyl donor and equimolar amounts of long-chain alcohols as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with LPL, palmityl oleate was synthesized, in a time- and dose-dependent manner. Apo-very low density lipoprotein (apoVLDL) stimulated LPL-catalyzed palmityl oleate synthesis. The apparent equilibrium ratio of fatty acid alcohol ester/oleic acid was estimated using a high concentration of LPL and a long (20 h) incubation period. The equilibrium ratio was affected by the incubation pH and the alcohol chain length. When the incubation pH was below pH 7.0 and long chain fatty acyl alcohols were used as substrates, the fatty acid alcohol ester/free fatty acid equilibrium ratio favored ester formation, with an apparent equilibrium ratio of fatty acid alcohol ester/fatty acid of about 0.9/0.1. The equilibrium ratio decreased sharply at alkaline pH (above pH 8.0). The ratio also decreased when fatty alcohols with acyl chains shorter than dodecanol were used. When a trioleoylglycerol/fatty acyl alcohol emulsion was incubated with LPL, fatty acid alcohol esters were synthesized in a dose- and time-dependent fashion. Fatty acid alcohol esters were easily synthesized from trioleoylglycerol when fatty alcohols with acyl chains longer than dodecanol were used, but synthesis was decreased with fatty alcohols with acyl chain lengths shorter than decanol, and little synthesizing activity was detected with shorter-chain fatty alcohols such as butanol or ethanol.

Animals↗
PubMed1999

Prevention by chitosan of myelotoxicity, gastrointestinal toxicity and immunocompetent organic toxicity induced by 5-fluorouracil without loss of antitumor activity in mice.

We examined the antitumor activity and side effects (myelotoxicity, immunocompetent organic toxicity and gastrointestinal toxicity) of combined treatment with the cancer chemotherapy drug 5-fluorouracil (5-FU) and dietary fiber chitosan in sarcoma 180-bearing mice. 5-FU (12.5 mg/kg x 2/day) plus chitosan (150, 375 and 750 mg/kg x 2/day) inhibited the tumor growth as well as 5-FU alone. Chitosan (150 and 750 mg/kg x 2/day) blocked the reduction of blood leukocyte number caused by 5-FU administration, and it prevented the injury of the small intestinal mucosa membrane and delayed the onset of diarrhea induced by 5-FU. Furthermore, chitosan (750 mg/kg x 2/day) prevented the reduction of spleen weight induced by 5-FU in sarcoma 180-bearing mice, and the reduction of lymphocyte and CD8+ T cell numbers induced by 5-FU was also prevented by the oral administration of chitosan (750 mg/kg x 2/day) in C57BL/6 mice. Chitosan (150 and/or 750 mg/kg x 2/day) reduced the 5-FU incorporation into RNA fractions of small intestine and spleen without affecting the 5-FU incorporation into the tumor in sarcoma 180-bearing mice. These findings suggest that prevention of the 5-FU side effects by chitosan might be partly due to the selective inhibition of 5-FU uptake into the small intestine and spleen, resulting in the reduction of immune function toxicity, myelotoxicity and gastrointestinal toxicity of 5-FU. Therefore, it is concluded that the combination of chitosan and 5-FU might be useful for the prevention of side effects such as gastrointestinal toxicity, immunotoxicity and myelotoxicity caused by 5-FU.

Animals↗