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Biomedical subjects

K Hirose

Publications and source records attributed to K Hirose.

At least 19 recordsLinked to original sources
PubMed2006

Hypercalcemia in childhood acute lymphoblastic leukemia: frequent implication of parathyroid hormone-related peptide and E2A-HLF from translocation 17;19.

Hypercalcemia is relatively rare but clinically important complication in childhood leukemic patients. To clarify the clinical characteristics, mechanisms of hypercalcemia, response to management for hypercalcemia, incidence of t(17;19) and final outcome of childhood acute lymphoblastic leukemia (ALL) accompanied by hypercalcemia, clinical data of 22 cases of childhood ALL accompanied by hypercalcemia (>12 mg/dl) reported in Japan from 1990 to 2005 were retrospectively analyzed. Eleven patients were 10 years and older. Twenty patients had low white blood cell count (<20 x 10(9)/l), 15 showed hemoglobin> or =8 g/dl and 14 showed platelet count > or =100 x 10(9)/l. Parathyroid hormone-related peptide (PTHrP)-mediated hypercalcemia was confirmed in 11 of the 16 patients in whom elevated-serum level or positive immunohistochemistry of PTHrP was observed. Hypercalcemia and accompanying renal insufficiency resolved quickly, particularly in patients treated with bisphosphonate. t(17;19) or add(19)(p13) was detected in five patients among 17 patients in whom karyotypic data were available, and the presence of E2A-HLF was confirmed in these five patients. All five patients with t(17;19)-ALL relapsed very early. Excluding the t(17;19)-ALL patients, the final outcome of ALL accompanied by hypercalcemia was similar to that of all childhood ALL patients, indicating that the development of hypercalcemia itself is not a poor prognostic factor.

Adolescent↗
PubMed2006

Resistance of infant leukemia with MLL rearrangement to tumor necrosis factor-related apoptosis-inducing ligand: a possible mechanism for poor sensitivity to antitumor immunity.

Malignant cells generally acquire some immune escape mechanisms for clonal expansion. Immune escape mechanisms also contribute to the failure of graft-versus-leukemia (GVL) effect after allogeneic hematopoietic stem cell transplantation (allo-SCT). Infant leukemias with mixed-lineage leukemia (MLL) rearrangement have a remarkably short latency, and GVL effect after allo-SCT has not been clearly evidenced in these leukemias. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)- and FasL-mediated cytotoxic pathways play important roles in cytotoxic T-lymphocyte- and natural killer cell-mediated antitumor immunity and optimal GVL activity. We investigated the in vitro sensitivity of MLL-rearranged acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML) cells to TRAIL- and FasL-mediated cytotoxicity. Most of cell lines and primary leukemia cells were highly resistant to TRAIL primarily owing to low cell-surface expression of death receptors in ALL and simultaneous expression of decoy receptors in AML. Nearly half of cell lines and majority of primary leukemia cells showed low sensitivity to FasL. These results suggest that resistance to death-inducing ligands, particularly to TRAIL, could be one of the mechanisms for a rapid clonal expansion and a poor sensitivity to the GVL effect in infant leukemias with MLL rearrangement.

Drug Resistance, Neoplasm↗
PubMed2006

Systematic review and meta-analysis: importance of CagA status for successful eradication of Helicobacter pylori infection.

BACKGROUND: Some, but not all studies have provided evidence that the CagA status of Helicobacter pylori strains is a predictive factor for the outcome of eradication therapy. AIM: To clarify the association between CagA status and eradication outcome. METHODS: We included studies reporting the numbers of successful and failed cases in H. pylori-eradication therapy according to the CagA status. Fourteen studies (1529 patients) were included of 325 articles identified in the search. The pooled risk ratio for H. pylori-eradication failure in CagA-negative relative to CagA-positive strains and the pooled risk difference in eradication success between the two groups were used as summary statistics. Meta-regression was used for examining the source of heterogeneity. RESULTS: The summary risk ratio for eradication failure in CagA-negative relative to CagA-positive was 2.0 (95% CI: 1.6-2.4, P < 0.001), corresponding with the summary risk difference for eradication success between the groups of 11% (95% CI: 3-19%, P = 0.011). Meta-regression analysis demonstrated that usage of polymerase chain reaction examination for CagA status and a high proportion of non-ulcer dyspepsia patients were factors for heterogeneity among studies. CONCLUSIONS: Our meta-analysis confirmed the importance of the presence of CagA as a predictor for successful eradication of H. pylori.

Antigens, Bacterial↗
PubMed2006

Influence of smoking and CYP2C19 genotypes on H. pylori eradication success.

CYP2C19 polymorphisms and smoking influence the efficacy of H. pylori eradication therapy, but interaction between the two have hitherto not been examined. A total of 142 H. pylori-positive patients who received triple drug therapy with lansoprazole, amoxicillin and clarithromycin were categorized into three groups with regard to diplotypes of CYP2C19: homozygous extensive metabolizer (homEM), heterozygous EM (hetEM), and poor metabolizer (PM). The overall success rate was 61.3%. Smoking was an independent risk factor of eradication failure (OR 2.81, 95% CI 1.14-6.91), whereas CYP2C19 polymorphisms were less influential. Among non-smokers, the homEM and hetEM groups showed worse eradication rates (58.5 and 67.3%) relative to PM (76.2%) as expected; however, an opposite trend was observed among smokers (homEM 50.0%, hetEM 46.7%, PM 20.0%), indicating possible interactions with CYP2C19 polymorphisms. Smoking has a greater influence on H. pylori eradication than the CYP2C19 genotype. Interaction between smoking and CYP2C19 should be examined in the future.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2006

Inhibition of NADPH oxidase 4 activates apoptosis via the AKT/apoptosis signal-regulating kinase 1 pathway in pancreatic cancer PANC-1 cells.

Pancreatic adenocarcinoma is an aggressive human malignancy and is characterized by resistance to apoptosis. Recently, NADPH oxidase (Nox) 4-mediated generation of intracellular reactive oxygen species (ROS) was proposed to confer antiapoptotic activity and thus a growth advantage to pancreatic cancer cells. The signaling mechanism by which Nox4 transmits cell survival signals remains unclear. Here, we show that both a flavoprotein inhibitor, diphenylene iodonium (DPI), and small interfering RNAs designed to target Nox4 mRNA (siNox4RNAs) inhibited superoxide production in PANC-1 pancreatic cancer cells, and depletion of ROS by DPI or siNox4RNAs induced apoptosis. Parallely, DPI treatment and siNox4RNA transfection blocked activation of the cell survival kinase AKT by attenuating phosphorylation of AKT. Furthermore, AKT phosphorylation of apoptosis signal-regulating kinase 1 (ASK1) on Ser-83 was reduced by DPI and siNox4RNAs. When ASK1Ser83Ala (an AKT phosphorylation-defective ASK1 mutant) was introduced into PANC-1 cells, this mutant alone induced apoptosis. But, addition of DPI or co-transfection of siNox4RNA had no additive effect, indicating that the mutant can substitute for these reagents in apoptosis induction. Taken together, these findings suggest that ROS generated by Nox4, at least in part, transmit cell survival signals through the AKT-ASK1 pathway in pancreatic cancer cells and their depletion leads to apoptosis.

Adenocarcinoma↗
PubMed2006

Improvement of wastewater treatment performance of the Fukashiba treatment plant.

The Fukashiba Treatment Plant Kashima Rinkai Specified Sewage Works has received wastewater from the petrochemical complex (90%) and public sewage of Kamisu and Hasaki town (10%). For this reason, the plant is facing many difficulties in producing good quality effluent. In order to solve these difficulties, we are reviewing the treatment performance and making efforts for its improvement with nitrification inhibition, control of bio-persistent substances and the PRTR approach.

Biodegradation, Environmental↗
PubMed2005

Soybean products and reduction of breast cancer risk: a case-control study in Japan.

Components of the Japanese diet, which might contribute to the relatively low breast cancer incidence rates in Japan, have not been clarified in detail. Since soybean products are widely consumed in Japan, a case-control study taking account of the menopausal status was conducted using data from the hospital-based epidemiologic research program at Aichi Cancer Center (HERPACC). In total, 167 breast cancer cases were included and 854 women confirmed as free of cancer were recruited as the control group. Odds ratios (OR) and 95% confidence intervals (95% CI) were determined by multiple logistic regression analysis. There were reductions in risk of breast cancer associated with high intake of soybean products among premenopausal women. Compared with women in the lowest tertile, the adjusted ORs for top tertile intake of tofu (soybean curd) was 0.49 (95% CI, 0.25-0.95). A significant decrease in premenopausal breast cancer risk was also observed for increasing consumption of isoflavones (OR=0.44; 95% CI, 0.22-0.89 for highest vs lowest tertile; P for trend=0.02). The present study found a statistically inverse association between tofu or isoflavone intake and risk of breast cancer in Japanese premenopausal women, while no statistically significant association was evident with the risk among postmenopausal women.

Adult↗
PubMed2005

Results after 24 years of prophylactic surgery for rheumatoid atlantoaxial subluxation.

We evaluated the use of surgical stabilisation for atlantoaxial subluxation after a follow-up of 24 years in 50 rheumatoid patients who had some degree of pain but no major neurological deficit. The mortality of patients treated by atlantoaxial fusion was significantly lower than for those who received conservative treatment. The deaths resulted from infection or comorbid conditions. The significantly high relative risks of mortality from conservative treatment compared with surgical treatment were mutilating disease and susceptible factors on both of the HLA-DRB1 alleles. Relief from pain and neurological and functional recovery were better, and the radiological degree of atlantoaxial translocation was less in those who were surgically treated compared with those who were not. Two patients had superficial local infections after surgery. We conclude that prophylactic atlantoaxial fusion is better than conservative treatment in these patients.

Arthritis, Rheumatoid↗
PubMed2004

Wet and dry deposition patterns of plutonium in Daejeon, Korea.

Plutonium in wet and dry deposition samples collected monthly at the Korea Institute of Nuclear Safety (KINS), Daejeon, Korea was determined during the period from January 2000 to August 2000. Monthly 239,240Pu deposition in Korea showed a maximum in the spring season (March to May), which was several times greater than that in Japan and corresponds to a seasonal cycle of soil dust fallout originating from the East Asian arid areas. The trajectory analysis of dust storms suggests that 239,240Pu deposition in Korea in spring is originating from plutonium-bearing surface soil particles from the East Asian arid areas. A significant part of the 239,240Pu deposition in spring in Korea is attributable to dry deposition.

Air Movements↗
PubMed2004

The elasticity of the MgSiO3 post-perovskite phase in the Earth's lowermost mantle.

MgSiO3 perovskite has been assumed to be the dominant component of the Earth's lower mantle, although this phase alone cannot explain the discontinuity in seismic velocities observed 200-300 km above the core-mantle boundary (the D" discontinuity) or the polarization anisotropy observed in the lowermost mantle. Experimental and theoretical studies that have attempted to attribute these phenomena to a phase transition in the perovskite phase have tended to simply confirm the stability of the perovskite phase. However, recent in situ X-ray diffraction measurements have revealed a transition to a 'post-perovskite' phase above 125 GPa and 2,500 K--conditions close to those at the D" discontinuity. Here we show the results of first-principles calculations of the structure, stability and elasticity of both phases at zero temperature. We find that the post-perovskite phase becomes the stable phase above 98 GPa, and may be responsible for the observed seismic discontinuity and anisotropy in the lowermost mantle. Although our ground-state calculations of the unit cell do not include the effects of temperature and minor elements, they do provide a consistent explanation for a number of properties of the D" layer.

Journal Article↗
PubMed2004

Plutonium isotopes in seas around the Korean Peninsula.

239+240Pu concentrations and 240Pu/239Pu atom ratios in coastal seas adjacent to the Korean Peninsula were determined, during the period 1999 to 2002, to assess the current distribution and to identify sources of Pu isotopes. 239+240Pu concentrations in surface waters ranged from 3.1 to 22.3 mBq m(-3) with higher concentrations in winter than in summer. 239+240Pu concentrations in seawaters around the Korean Peninsula are greater than that in the western North Pacific. 240Pu/239Pu atom ratios ranged from 0.18 to 0.33 with an average value of 0.25+/-0.03, which is significantly higher than the global fallout average. The 240Pu/239Pu atom ratios of the 2000 m deep entire water column in the south western part of the East Sea (Sea of Japan) was comparable to that observed in waters near Bikini Atoll. The higher 240Pu/239Pu atom ratios than that of global fallout may be explained by the hypothesis that the earlier input signal of low 240Pu/239Pu atom ratio (0.18-0.19) of global fallout plutonium in seas adjacent to the Korean Peninsula is being gradually diluted by the high 240Pu/239Pu atom ratio plutonium transported from the tropical Pacific Proving Grounds via prevailing ocean current.

Journal Article↗
PubMed2004

Experience with steroid-free maintenance immunosuppression in simultaneous pancreas-kidney transplantation.

INTRODUCTION: Steroid avoidance is possible in simultaneous pancreas-kidney transplantation with the use of newer immunosuppressive agents and induction therapy. We undertook a retrospective consecutive case review of patients treated at a university tertiary referral center. METHODS: Medical records of 44 consecutive patients receiving a pancreas-kidney transplant from November 2000 to September 2002 were reviewed. The immunosuppression protocol used in this series of patients consisted of thymoglobulin induction, combined with mycophenolate mofetil, tacrolimus, and sirolimus for maintenance immunosuppression. Steroids were used only while thymoglobulin was given and were typically discontinued by postoperative week 1. Main outcome measures included graft and patient survival rates, rejection rates of the kidney or pancreas, infection rates, and surgical complication rates. RESULTS: All 44 patients received a kidney-pancreas transplant with systemic venous anastomosis and enteric drainage of the pancreas. Patient kidney, and pancreas survival rates were 95.6%, 93.2%, and 88.7%, respectively. Biopsy-proven pancreas rejection rates at 1 and 6 months posttransplant were 2.3% and 2.3%. Kidney rejection rates at 1 and 6 months were 2.3% and 4.6%. Reasons for patient loss included one death from sepsis and one cardiovascular death. Reasons for kidney loss besides death included a thrombotic microangiopathy. Reasons for pancreas loss included three thromboses, one mild rejection/infection, and one duodenal segment leak with infection. All patients who have been free of rejection have been off steroids for the duration of follow-up. CONCLUSIONS: Newer immunosuppression protocols without maintenance steroids are possible with minimal rejection in the first 3 months and equivalent patient and graft survival rates compared with earlier protocols utilizing steroids. The potential beneficial long-term impact of steroid avoidance will require further study.

Cause of Death↗
PubMed2004

Characterization of a point mutation in the parC gene of Mycoplasma bovirhinis associated with fluoroquinolone resistance.

Quinolone-resistant (QR) mutants of Mycoplasma bovirhinis strain PG43 (type strain) were generated by stepwise selection in increasing concentrations of enrofloxacin (ENR). An alteration was found in the quinolone resistance-determining region (QRDR) of the parC gene coding for the ParC subunit of topoisomerase IV from these mutants, but not in the gyrA, gyrB, and parE gene coding for the GyrA and GyrB subunits of DNA gyrase and the ParE subunit of topoisomerase IV. Similarly, such an alteration in QRDR of parC was found in the field isolates of M. bovirhinis, which possessed various levels of QR. The substitution of leucine (Leu) by serine (Ser) at position 80 of QRDR of ParC was observed in both QR-mutants and QR-isolates. This is the first report of QR based on a point mutation of the parC gene in M. bovirhinis.

Animals↗
PubMed2003

Temporal variation of 137Cs water column inventory in the North Pacific since the 1960s.

The temporal variation of water column inventories of 137Cs in the North Pacific since the 1960s was examined based on the analysis of the 137Cs profiles in HAM database. 137Cs in seawater in the North Pacific have originated mainly from global fallout from atmospheric nuclear weapons tests, which occurred in the early 1960s. In the 1960s, both the meridional distribution of 137Cs inventory in the North Pacific and that of fallout on land stations showed mid-latitude maximum. The region with higher deposition at land stations, however, was more northern than the latitudes where the 137Cs inventory in the North Pacific showed a maximum. The difference of the latitude where maximum 137Cs deposition/inventory was observed reflects the difference of the geographical distribution of the precipitation amount in the Pacific and Atlantic Oceans followed by the different warm current systems in each ocean. A good positive relation between 137Cs inventory and annual precipitation amount was discovered in the ocean stations at the middle latitude in the North Pacific. The horizontal distribution of 137Cs inventories at the middle latitudes in the North Pacific is characterized as west-high and east-low in the early 1960s, which was basically controlled by the distribution of annual precipitation amount. Eastward advection, then, modified it to be less difference in 1966-1967 after the highest deposition periods in 1963-1965. In the 1970s and 1980s, increases of the 137Cs inventory at the lower latitude of 10-20 deg. N are found. Surface and subsurface southward transports are considered as the source of this increasing 137Cs inventory.

Cesium↗
PubMed2003

Sensitivity of genera Porphyromonas and Prevotella to the bactericidal action of C-terminal domain of human CAP18 and its analogues.

This paper reports the effect of the synthesized 27-amino acid sequence in the C-terminal domain of human CAP18 (hCAP18), a human cationic antibacterial protein or cathelicidin, on certain strains belonging to the genera Porophyromonas and Prevotella. The domain binds lipopolysaccharides (LPS) from Porophyromonas gingivalis and Porophyromonas circumdentaria as well as enterobacterial LPS. Two analogues of hCAP18, designated LL/CAP18 and FF/CAP18, were also tested to determine whether additional activity was obtained. The analogue peptides replaced with hydrophobic and cationic amino acid residues showed more potent bactericidal and LPS-binding activities than the original one.

Antimicrobial Cationic Peptides↗
PubMed2003

Isolation of Mycoplasmas from nasal swabs of calves affected with respiratory diseases and antimicrobial susceptibility of their isolates.

Nasal swabs of 293 calves were examined for Mycoplasma. The samples were collected from calves affected with respiratory diseases on 71 farms in various parts of Japan between 1996 and 1997. Mycoplasma bovirhinis was isolated from 47 of 293 calves (16.0%). Mycoplasma alkalescens, M. bovis, M. arginini, M. bovigenitalium and Acholeplasma spp. were isolated from 19 (6.5%), seven (2.4%), four (1.4%), four (1.4%) and 18 (6.1%) calves, respectively. Pasteurella multocida and P. haemolytica were isolated from 60% of Mycoplasma-positive calves. However, other bacteria were not isolated from calves. To evaluate the antimicrobial susceptibility of their isolates, 68 M. bovirhinis, 21 M. alkalescens and 10 M. bovis strains were examined for 12 antimicrobial agents. All isolates showed higher susceptibility to tiamulin than to the other drugs used in the study. However, erythromycin had no effect on any of the Mycoplasma strains studied. The field isolates were less susceptible than the type strains to some drugs, such as spiramycin, oxytetracycline and tylosin.

Animals↗
PubMed2003

Fish consumption and colorectal cancer: a case-reference study in Japan.

Several clinical studies have suggested that supplementation with fish oils can suppress the proliferation of colorectal mucosa and therefore inhibit the development of colorectal cancer. However, epidemiological evidence concerning fish consumption and risk is inconsistent and limited. To clarify the association between intake of fish and the likelihood of developing colorectal cancer, we conducted a large sample size case-reference study with 928 cases of colon cancer, 622 of rectal cancer and 46886 cancer-free outpatient references aged 40-79 years. The data showed frequent raw/cooked fish intake to be associated with decreased odds ratio (OR) 0.68 with 95% confidence interval (CI) 0.47-0.99 for male colon cancer, especially for males aged over 60 years, smokers and frequent meat eaters. A marginal decrease in the OR (OR 0.58, 95% CI 0.31-1.07) was also detected for female rectal cancer, especially in the regular physical exercise subgroup. However, frequent dried/salted fish intake was found to be associated with increased OR in females younger than 60 years old and alcohol drinkers. Although there is some possible bias in epidemiological studies, the results suggest that frequent raw/cooked fish intake may decrease the risk while dried/salted fish, in contrast, may exert a detrimental effect.

Adult↗