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Hiroshi Maruyama

Publications and source records attributed to Hiroshi Maruyama.

At least 19 recordsLinked to original sources
PubMed2026

A comparative analysis of the clinical and genomic characteristics of Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus in Korea and Japan.

Panton-Valentine leukocidin (PVL) is a leukocyte-lytic toxin produced by Staphylococcus aureus, which is primarily associated with skin and soft tissue infections. Notably, there has been an increase in the number of cases caused by the USA300 lineage in Japan. However, the reported prevalence of USA300 is limited in other Asian countries, including Korea. This study investigated the prevalence of PVL-positive methicillin-resistant S. aureus (MRSA) in Korea and Japan and compared their molecular epidemiological characteristics. A total of 463 MRSA strains were analyzed, comprising 283 strains from patients visiting two hospitals in Seongnam and Seoul, Korea, and 180 strains from six hospitals in Tokyo, Japan, between 2018 and 2019. The PVL-encoding genes lukS/F-PV were detected using PCR. Molecular epidemiological and phylogenetic analyses were performed using next-generation sequencing. Overall, 27 (9.5%) PVL-positive MRSA strains were detected among strains isolated from Korea, and 16 (8.9%) were detected among those isolated from Japan. Genotyping of PVL-positive strains revealed that 85.2% of Korean and 81.3% of Japanese strains belonged to USA300. Most USA300 strains from Japan and Korea formed distinct clusters in phylogenetic analyses. Meanwhile, ΨUSA300 and ST22-PT, clones that are prevalent in Japan, were isolated in Korea. This study showed that USA300 strains, which are becoming more prevalent in Japan, are also present in Korea. Furthermore, this study suggests that ΨUSA300 and ST22-PT may be spreading between these two countries. Therefore, it is necessary to continue monitoring the epidemiological trends of PVL-positive MRSA clones both domestically and internationally.IMPORTANCEPanton-Valentine leukocidin (PVL) is a major toxin produced by Staphylococcus aureus. Although a rapid increase in PVL-positive strains has been reported in Japan, data on PVL-positive strains in Korea remain limited. In this study, we performed a comparative analysis of PVL-positive S. aureus isolates from Korea and Japan. The results showed that the clinical backgrounds and genetic profiles of PVL-positive strains isolated in Korea and Japan were highly similar. Furthermore, we confirmed for the first time that clones circulating in Japan, including ΨUSA300 and ST22-PT, were also isolated in Korea. These findings provide valuable insights into the epidemiological status of PVL-positive S. aureus in East Asia.

Leukocidins↗
PubMed2006

Regulation of proopiomelanocortin gene transcription during single and repeated immobilization stress.

We have previously reported that repeated immobilization produces persistent activation of the hypothalamic-pituitary-adrenocortical axis in rats. In an attempt to assess whether any adaptational responses occur at the pituitary level, we examined the detailed time courses of proopiomelanocortin (POMC) gene transcription in the anterior pituitary (AP) in comparison with those of corticotropin-releasing hormone (CRH) gene transcription in the hypothalamic paraventricular nucleus (PVN) during single and repeated immobilization using both intronic and exonic probes. During single immobilization, there was a robust and rapid increase in both CRH heteronuclear RNA (hnRNA) in the PVN and POMC hnRNA in the AP, together with a slower increase in CRH mRNA, but no significant increase in POMC mRNA. Single immobilization also caused significant increases in the plasma concentrations of both ACTH and corticosterone. Daily immobilization for 6 days increased the basal levels of CRH hnRNA and CRH mRNA in the PVN and POMC mRNA in the AP. Both CRH hnRNA and POMC hnRNA responded rapidly to a final episode of acute immobilization on day 7, whereas the peak values of CRH hnRNA and POMC hnRNA after 15 min of the final stress were smaller than those during single immobilization. In contrast to single stress, CRH mRNA did not change significantly, whereas POMC mRNA robustly increased after the final immobilization on day 7. Plasma ACTH increased to a similar degree to single stress, but its initial increase at 5 min was significantly higher than that during single immobilization. The increase in the plasma corticosterone concentration was higher during final immobilization than during single stress. These results suggest that, in response to the hypothalamic drive during repeated immobilization stress, pituitary corticotrophs are capable of upregulating the basal and stress-induced POMC mRNA levels via increased efficiency of the posttranscriptional processing of the hnRNA and/or increased mRNA stability.

Adrenocorticotropic Hormone↗
PubMed2006

Speciation of sulfate in size-fractionated aerosol particles using sulfur K-edge X-ray absorption near-edge structure.

X-ray absorption near-edge structure (XANES) at sulfur K-edge was used to determine the sulfate species present in size-fractionated aerosol particles based on the postedge structure after the main absorption peak in the XANES region. A comparison of the XANES spectra of reference sulfate materials and aerosol samples collected in Tsukuba in Japan clearly showed that (NH4)2SO4 was the main sulfur species in particles with a smaller diameter and CaSO4 x 2H2O (gypsum) was the main sulfur species in particles with a larger diameter. A simulation of the XANES spectra by reference materials allows us to obtain the quantitative mixing ratios of the different sulfate species present in the aerosol samples. The presence of minor sulfur species other than (NH4)2SO4 and gypsum at the surface of mineral aerosols is suggested in our simulations and by a surface-sensitive conversion electron/He-ion yield XANES. In the absence of a contribution from a large dust event, the mole concentration of gypsum in the mineral aerosol fraction (particle diameter > 1 microm) determined by XANES is similar to that of Ca which is determined independently using ion chromatography. This shows that the Ca and sulfate in the mineral aerosols are present only as gypsum. Considering that calcite is the main Ca mineral in the original material arising from an arid and semiarid area in China, it is strongly suggested that gypsum is formed in aerosol during its long-range transportation by a reaction between calcite and sulfate ions.

Absorptiometry, Photon↗
PubMed2006

[A case of non-curatively resected colon cancer with liver and lymph node metastases treated by TS-1/CPT-11 combination therapy].

The patient was a 66-year-old male who had descending colon cancer with multiple liver metastases and paraaortic lymph node metastases. He underwent a left colectomy with lymph node dissection, but the operation resulted in curability C. The serum CEA level before the operation was 205.5 ng/ml. After 2 courses of 5-FU/LV as first-line chemotherapy, this treatment could not be continued due to grade 3 anorexia. As second-line chemotherapy, the patient was treated with daily oral administration of TS-1 (100 mg/day) for 3 weeks. Due to grade 3 anorexia, this treatment could not be continued. Tailored TS-1/CPT-11 (TS-1 80 mg/day from day 1 to day 21, CPT-11 65 mg/m(2) day 1, 15) combination therapy was then chosen as third-line chemotherapy. After 6 courses of combination therapy, the tumor marker (CEA) was decreased and para-aortic lymph nodes could not be detected by computed tomography (CT). Only grade 1 fatigue was noted as an adverse reaction to the treatment. The patient's good QOL was achieved during follow-up over 24 months with the cancer controlled. This case suggests that patients with non-curative resected colon cancer could benefit from TS-1/CPT-11 combination therapy as a second-line or third-line treatment.

Adenocarcinoma↗
PubMed2005

Susceptibility alleles and haplotypes of human leukocyte antigen DRB1, DQA1, and DQB1 in autoimmune polyglandular syndrome type III in Japanese population.

BACKGROUND: It has been reported that HLA class II haplotypes DRB1*0405-DQA1*0303-DQB1*0401 and DRB1*0901-DQA1*0302-DQB1*0303 are major susceptibility haplotypes for type 1 diabetes mellitus (DM) in Japanese population. However, little has been reported on the susceptibility HLA class II haplotypes in Japanese patients with autoimmune polyglandular syndrome type II and type III (APS III). PATIENTS AND METHODS: HLA class II haplotypes of DRB1-DQA1-DQB1 in 31 patients with APS III, 14 patients with Hashimoto's thyroiditis alone, and 15 patients with Graves' disease alone were examined in Japanese population. APS III patients were divided into three groups (A, B, and C) depending on the combination of autoimmune endocrine diseases. RESULTS: In 13 APS III patients with both Hashimoto's thyroiditis and type 1 DM (group A), the haplotype frequencies of the HLA DRB1*0802-DQA1*0401-DQB1*0402 and DRB1*0901-DQA1*0302-DQB1*0303 were significantly higher than in the controls. In patients with Hashimoto's thyroiditis alone, the haplotype frequency of DRB1*0901-DQA1*0302-DQB1*0303 was significantly higher than in controls, whereas the frequency of DRB1*0802-DQA1*0401-DQB1*0402 did not differ significantly from those in the controls. In 11 APS III patients with both Graves' disease and type 1 DM (group B), the haplotype frequencies of HLA DRB1*0405-DQA1*0303-DQB1*0401 and DRB1*0802-DQA1*0301-DQB1*0302 were significantly higher than in controls. In patients with Graves' disease alone, the haplotype frequency of DRB1*0803-DQA1*0103-DQB1*0601 were significantly higher than those in controls, suggesting that the susceptibility haplotypes for group B APS III differed from those for Graves' disease alone. In 7 APS III patients with both autoimmune thyroid diseases and pituitary disorders (group C), the haplotype frequency of HLA DRB1*0405-DQA1*0303-DQB1*0401 was significantly higher than in controls. CONCLUSIONS: Susceptible HLA class II haplotypes of DRB1-DQA1-DQB1 for APS III differ between the Japanese and Caucasian populations. More interestingly, the susceptible HLA class II haplotypes differ among the three types of Japanese APS III and are not merely a combination of susceptibility haplotypes of each endocrine disease.

Adult↗
PubMed2005

Immune thrombocytopenic purpura associated with rheumatoid arthritis: case report.

A 54-year-old Japanese woman was diagnosed with rheumatoid arthritis (RA) in 1995 on the basis of symmetric effusive polyarthritis, morning stiffness, and strongly positive rheumatoid factor. She had received low-dose prednisolone, indomethacin, methotrexate (MTX), and cyclophosphamide (CPA), at least, over 4 years before the current admission and showed partial improvement of polyarthralgia. In November 2002, she suddenly developed thrombocytopenia (platelet count was 0.3 x 10(4) mm(-3)) with purpura and was diagnosed with immune thrombocytopenic purpura (ITP). As she had refractory ITP, the administration of pulsed high-dose dexamethasone (DEX) therapy was started, resulting in the complete remission of ITP. The present paper reports that pulsed high-dose DEX therapy was useful for the treatment of refractory ITP associated with RA.

Anti-Inflammatory Agents↗
PubMed2005

The relationship of tryptase- and chymase-positive mast cells to angiogenesis in stage I non-small cell lung cancer.

OBJECTIVE: There are two types of human mast cells, tryptase-positive mast cells (MC(T)) and tryptase- and chymase-positive mast cells (MC(TC)). Although MC(T) have been reported to be related to the generation of angiogenesis, little is known about the involvement of MC(TC) in tumor angiogenesis. In this study, to clarify the relationship between MC(TC) and lung cancer angiogenesis, we evaluated MC(TC), MC(T), and microvessel counts in normal, border, and central lung cancer regions. METHODS: Tumor sections from 32 cases of adenocarcinoma and 13 cases of squamous cell carcinoma were immunostained for chymase to evaluate MC(TC), tryptase to evaluate MC(T,) and CD34 to evaluate microvessel counts. RESULTS: Both MC(TC) and MC(T) counts in the border lung cancer region were significantly higher than in the central region, and the MC(TC) and MC(T) counts in the central region were significantly higher than those in the normal regions. The microvessel counts in the border region were higher than those in the central region. The ratio of MC(TC) to MC(T) in the border region, but not in the central region, was significantly higher than that in the normal region. In the border region, significant correlations not only between MC(T) and microvessel count, but also between MC(TC) and microvessel count were observed. In the central region, a significant correlation between MC(TC) and the microvessel count was observed, but there was no significant correlation between MC(T) and the microvessel count. CONCLUSIONS: These findings suggest that MC(TC) may be involved in the pathogenesis of angiogenesis in lung cancer.

Adenocarcinoma↗
PubMed2004

Electrophysiological characterization of the tetrodotoxin-resistant Na+ channel, Na(v)1.9, in mouse dorsal root ganglion neurons.

Small dorsal root ganglion neurons express preferentially the Na+ channel isoform Na(v)1.9 that mediates a tetrodotoxin-resistant (TTX-R) Na+ current. We investigated properties of the Na+ current mediated by Na(v)1.9 (I(NaN)) using the whole-cell, patch-clamp recording technique. To isolate I(NaN) from heterogeneous TTX-R Na+ currents that also contain another type of TTX-R Na+ current mediated by Na(v)1.8, we used Na(v)1.8-null mutant mice. When F- was used as an internal anion in the patch pipette solution, both the activation and inactivation kinetics for I(NaN) shifted in the hyperpolarizing direction with time. Such a time-dependent shift of the kinetics was not observed when Cl- was used as an internal anion. Functional expression of I(NaN) declined with time after cell dissociation and recovered during culture, implying that Na(v)1.9 may be regulated dynamically by trophic factors or depend on subtle environmental factors for its survival. During whole-cell recordings, the peak amplitude of I(NaN) increased dramatically after a variable delay, as if inactive or silent channels had been "kindled". Such an unusual increase of the amplitude could be prevented by adding ATP to the pipette solution or by recording with the nystatin-perforated patch-clamp technique, suggesting that the rupture of patch membrane affected the behaviour of Na(v)1.9. These peculiar properties of I(NaN) may provide an insight into the plasticity of Na+ channels that are related to pathological functions of Na+ channels accompanying abnormal pain states.

Adenosine Triphosphate↗
PubMed2003

Use-dependent removal of the 4-aminopyridine-induced block of the transient K+ current in rat dorsal root ganglia.

Effects of 4-aminopyridine (4-AP) on the transient K(+) current (I(A)) was studied in rat sensory neurons using the whole cell patch-clamp technique. The amplitude of I(A) was reduced by 4-AP. The steady-state inactivation curve for I(A) was shifted in the positive direction by 4-AP, suggesting that the blocking action of 4-AP may be attenuated by membrane depolarization. When two I(A)s were evoked with variable intervals, the peak amplitude of the I(A) induced by the second pulse was augmented in the presence of 4-AP. These results indicate that the action of 4-AP can be modulated by concurrent neuronal activities.

4-Aminopyridine↗
PubMed2003

[Effect of nedaplatin, 5-FU, and leucovorin combined with radiation therapy in unresectable esophageal carcinoma].

A 51-year-old male was assessed as having esophageal squamous cell carcinoma with trachea invasion and cervical lymph node metastasis. After one course of chemotherapy using cisplatin (CDDP), 5-fluorouracil (5-FU) and Leucovorin (LV), the patient had progressive disease (PD) of the primary lesion and metastatic lymph nodes, and a side effect of severe nausea. One course of nedaplatin, 5-FU and LV combined with radiation was performed alternatively. The effect was evaluated as a partial response (PR) of the primary lesion and metastatic lymph nodes. There were no adverse side effects such as nausea or renal dysfunction except for pancytopenia of grade 2. Increased serum levels of vascular endothelial growth factor (s-VEGF) decreased after the chemoradiotherapy and increased again during continued radiotherapy alone. More information is needed as to whether changes in s-VEGF relate to the clinical effects of the treatment.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Role of L-selectin in the development of ventilator-associated pneumonia in patients after major surgery.

BACKGROUND: The circulating level of soluble L-selectin (sL-selectin) has been reported to be low in adult respiratory distress syndrome and acute lung injury. This study explores the role of L-selectin in the development of ventilator-associated pneumonia (VAP) in patients undergoing major surgery. PATIENTS AND METHODS: Thirty-four patients who underwent esophagectomy were maintained by mechanical ventilation in a surgical intensive care unit. Fourteen patients developed VAP by postoperative day (POD) 7, while 20 patients did not. The plasma levels of soluble adhesion molecules and elastase were measured serially by ELISA or EIA. The expression of L-selectin on polymorphonuclear neutrophils (PMNs) was analyzed by flow cytometry. RESULTS: In multiple logistic regression analysis, only the preoperative plasma level of sL-selectin was significantly associated with VAP. The plasma sL-selectin level before surgery was significantly lower in the patients who developed VAP compared with the patients who did not develop VAP. After surgery, the level of sL-selectin did not change. The plasma level of soluble intercellular adhesion molecule-1 increased in the patients with and without VAP. The plasma level of soluble vascular cell adhesion molecule-1 was significantly higher in the patients with VAP. L-selectin expression on PMNs showed a peak on POD 2 in the patients without VAP, whereas it was impaired in the patients with VAP. CONCLUSIONS: Determination of the preoperative plasma level of sL-selectin may help to identify patients at high risk for VAP after esophagectomy.

Cell Adhesion Molecules↗
PubMed2002

Mutation analysis of the TSC1 and TSC2 genes in Japanese patients with pulmonary lymphangioleiomyomatosis.

Pulmonary lymphangioleiomyomatosis (LAM) is a destructive lung disease characterized by a diffuse hamartomatous proliferation of smooth muscle cells (LAM cells) in the lungs. Pulmonary LAM can occur as an isolated form (sporadic LAM) or in association with tuberous sclerosis complex (TSC) (TSC-LAM), a genetic disorder with autosomal dominant inheritance with various expressivity resulting from mutations of either the TSC1 or TSC2 gene. We examined mutations of both TSC genes in 6 Japanese patients with TSC-LAM and 22 patients with sporadic LAM and identified six unique and novel mutations. TSC2 germline mutations were detected in 2 (33.3%) of 6 patients with TSC-LAM and TSC1 germline mutation in 1 (4.5%) of 22 sporadic LAM patients. In accordance with the tumor-suppressor model, loss of heterozygosity (LOH) was detected in LAM cells from 3 of 4 patients with TSC-LAM and from 4 of 8 patients with sporadic LAM. Furthermore, an identical LOH or two identical somatic mutations were demonstrated in LAM cells microdissected from several tissues, suggesting LAM cells can spread from one lesion to another. Our results from Japanese patients with LAM confirmed the current concept of pathogenesis of LAM: TSC-LAM has a germline mutation but sporadic LAM does not; sporadic LAM is a TSC2 disease with two somatic mutations; and a variety of TSC mutations causes LAM. However, our study indicates that a fraction of sporadic LAM can be a TSC1 disease; therefore, both TSC genes should be examined, even for patients with sporadic LAM.

Chromosomes, Human, Pair 16↗
PubMed2002

Purification and characterization of heparinase that degrades both heparin and heparan sulfate from Bacillus circulans.

A heparinase that degrades both heparin and heparan sulfate (HS) was purified to homogeneity from the cell-free extract of Bacillus circulans HpT298. The purified enzyme had a single band on SDS-polyacrylamide gel electrophoresis with an estimated molecular mass of 111,000. The enzyme showed optimal activity at pH 7.5 and 45 degrees C, and its activity was stimulated in the presence of 5 mM CaCl2, BaCl2, or MgCl2. Analysis of substrate specificity and degraded disaccharides demonstrated that the enzyme acts on both heparin and HS, similar to heparinase II from Flavobacterium heparinum.

Bacillus↗
PubMed2002

[Lissencephaly].

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Brain↗