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Biomedical subjects

K Ohno

Publications and source records attributed to K Ohno.

At least 37 records · Page 2Linked to original sources
PubMed2005

Arsenic contamination of groundwater in Nawabganj, Bangladesh, focusing on the relationship with other metals and ions.

Serious arsenic contamination of groundwater in Bangladesh has been frequently reported and is of great concern. In this research, repeated water sampling from the same 10 tubewells in Nawabganj municipality, Bangladesh, was conducted and analysed, focusing on the seasonal variation of water quality and the relationship among arsenic and other metals and ions. For the seasonal variation of water quality, arsenic and iron concentrations were higher in the rainy season in general although the tendency was not consistent and it depended on the tubewell and the time. Correlation between arsenic and iron could not be observed in this study (r = -0.01) when using all cases. This was because no correlation was observed in the higher arsenic concentration range. Arsenic removal by co-precipitation with coexisting iron is known as one of the locally applicable techniques in Bangladesh, but the result from this study suggests that some additional treatments such as the extra injection of iron should be performed in some cases, especially where the arsenic concentration is high. The correlation between arsenic and other substances was also analysed. As a result, manganese (r = 0.37), molybdenum (r = 0.33) and sulfate ion (r = -0.33) significantly correlated with arsenic (p < 0.05). The negative correlation between arsenic and sulfate ion implies the dissolution of arsenic into groundwater under reductive conditions although there are some exceptional cases.

Arsenic↗
PubMed2004

Enhanced electron-capture decay rate of 7Be encapsulated in C60 cages.

The decay rate of 7Be electron capture was measured in C60 and Be metal with a reference method. The half-life of 7Be endohedral C60 ((7)Be@C(60)) and 7Be in Be metal (Be metal (7Be)) is found to be 52.68+/-0.05 and 53.12+/-0.05 days, respectively. This amounts to a 0.83% difference in electron-capture decay half-life between (7)Be@C(60) and Be metal (7Be). Our result is a reflection of the different electron wave functions for (7)Be@C(60) inside C60 compared to the situation when 7Be is in a Be metal.

Journal Article↗
PubMed2004

Progressive myopathy with circulating autoantibody against giantin in the Golgi apparatus.

A woman aged 59 years with adult-onset progressive myopathy had anti-Golgi (giantin) autoantibody in the serum. Limb-muscle biopsy revealed chronic myopathy with paucity of cellular reactions and reduced immunostaining for alpha-dystroglycan. The similarity of the current patient with cases of hereditary alpha-dystroglycanopathies (Fukuyama-type congenital muscular dystrophy, Walker-Warburg syndrome, muscle-eye-brain disease, congenital muscular dystrophy type 1C, and limb-girdle muscular dystrophy type 2I) suggests that the Golgi apparatus is the target organelle in a subset of myopathies.

Antibody Specificity↗
PubMed2004

Identification of peptides containing T-cell epitopes of Japanese cedar (Cryptomeria japonica) pollen allergen (Cry j 1) in dogs.

Japanese cedar (Cryptomeria japonica, CJ) pollen has been known to cause atopic dermatitis in dogs in Japan. However, since the mechanism of the CJ antigen recognition is not well understood in dogs, it is difficult to develop effective immunotherapy for atopic dermatitis caused by sensitization to CJ pollen. In order to aim at development of a peptide immunotherapy, we tried to identify T-cell epitopes of a major allergen of CJ pollen, Cry j 1, in dogs sensitive to CJ pollen allergen. Peripheral blood mononuclear cells (PBMCs) obtained from 22 dogs experimentally sensitized to CJ pollen allergen and 5 atopic dogs sensitive to CJ pollen allergen were used for mapping of T-cell epitopes of Cry j 1 using 35 kinds of synthesized overlapping peptides of Cry j 1. Reactive peptides were identified based on the results of blastogenic responses of PBMCs against the peptides when the stimulation indices were beyond 2.0. Three reactive peptides were identical in a relatively high population of experimental dogs, which were Nos. 8 (p71-90) (41%), 10 (p91-110) (50%), and 11 (p101-120) (41%). It was considered that these synthesized peptides should contain T-cell epitopes of Cry j 1 in the dogs. However, there were no reactive peptides identical among the five atopic dogs spontaneously sensitive to CJ pollen. The population of dogs experimentally sensitized to CJ pollen antigen will be used in order to investigate effects of a peptide immunotherapy using the reactive peptides. The results in atopic dogs sensitive to CJ pollen antigen will also provide useful information on necessity to develop a tailor-made immunotherapy using reactive peptides in each dog.

Allergens↗
PubMed2004

Increase of CC chemokine receptor 4-positive cells in the peripheral CD4 cells in dogs with atopic dermatitis or experimentally sensitized to Japanese cedar pollen.

BACKGROUND: Since dogs frequently develop allergic diseases, similar to those in humans, dogs represent a possible animal model for allergy in humans. In human atopic dermatitis (AD), CC chemokine receptor 4 (CCR4) has been shown to play an important role in the development of allergic inflammation of AD; however, the association between allergic reaction and CCR4 is not well understood in dogs. OBJECTIVE: To examine CCR4 expression in peripheral blood CD4+ cells in dogs that had AD and were experimentally sensitized with Japanese cedar pollen. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from 17 dogs with AD. The proportion of CCR4+ cells in peripheral blood CD4+ cells (CCR4/CD4) was evaluated by flow cytometry and compared with that in 10 healthy dogs. Similarly, in dogs that were experimentally sensitized to Japanese cedar pollen antigen, the proportion of CCR4/CD4 was examined pre- and post-sensitization. RESULTS: The proportion of CCR4/CD4 in dogs with AD was 40.3+/-3.3%, which was significantly higher than that in normal dogs (23.6+/-4.3%) (P<0.01). In the experimentally sensitized dogs, the proportion of CCR4/CD4 was 25.4+/-2.6% at pre-sensitization and it was significantly increased (29.8+/-2.9%) at post-sensitization (P<0.01). CONCLUSION: The proportion of CCR4+ cells in peripheral blood CD4+ cells was measured in dogs with allergic conditions. The present findings indicate that CCR4+ cells may be involved in the pathogenesis of allergy in dogs as in humans.

Allergens↗
PubMed2004

Alternatively spliced transcripts of Fas mRNAs in feline lymphoid cells.

Fas belongs to the tumour necrosis factor receptor family and transduces the death signal after binding to the Fas ligand. Five feline lymphoma cell lines were shown, by reverse transcription-polymerase chain reaction, to express six species of Fas transcripts. Based on sequence comparison of these Fas transcripts with the genomic Fas gene, five of the six transcripts were found to be generated through alternative splicing and to encode five different Fas proteins lacking the transmembrane domain. We also detected such alternatively spliced transcripts in primary tumour tissues from cats with naturally occurring lymphoma. These results suggest a possible association of the alternatively spliced Fas variants with the pathogenesis of feline lymphoma.

Alternative Splicing↗
PubMed2004

Mineralized bone loss in partially edentulous trabeculae of ovariectomized rabbit mandibles.

OBJECTIVE: The purpose of this study was to evaluate trabeculae changes in partially edentulous bone in ovariectomized rabbits. BACKGROUND: Numerous clinical studies have suggested that the greater risk for oral bone loss in females may be correlated with osteoporosis after menopause. Knowledge of trabecular changes in partially edentulous bone in animals with loss of ovarian function may be beneficial in the diagnosis and treatment of partially edentulous patients of postmenopausal women. METHODS: Twelve adult female Japanese white rabbits were examined. The mandibular incisors were initially extracted to simulate the partially edentulous bone. Six animals were bilaterally ovariectomized and the other six sham-ovariectomized 12 weeks after tooth extraction. The partially edentulous parts of distal mandibular bodies were processed undecalcified 12 weeks after ovariectomized or sham-ovariectomized surgeries and examined by quantitative trabecular bone histomorphometry. RESULTS: In ovariectomized rabbits, there were significant increases in trabecular separation, osteoid volume, osteoid thickness, osteoid width, eroded surface, and mineral apposition rate, and a significant decrease in trabecular number. CONCLUSION: The results of sparser trabecular structure, more trabecular osteoid, and increased trabecular bone turnover demonstrate mineralized bone loss in partially edentulous trabeculae of ovariectomized rabbit mandibles and suggest that the same loss may occur in postmenopausal women.

Analysis of Variance↗
PubMed2004

Treatment of chronic lymphocytic leukaemia in three dogs with melphalan and prednisolone.

Three adult dogs with chronic lymphocytic leukaemia (CLL) were successfully treated with melphalan and prednisolone. Based on the immunophenotypic analysis of leukaemic cells, two dogs were diagnosed with B cell CLL and one dog was tentatively diagnosed as having T cell CLL. One dog with B cell CLL had IgM monoclonal gammopathy. The clinical signs and haematological abnormalities associated with CLL in the three dogs improved with the administration of cytoreductive melphalan (3 to 5 mg/m2/day) and prednisolone (4.3 to 30 mg/m2/day) for eight to 210 days. There were no severe adverse effects except a mild increase in plasma alkaline phosphatase activity. Melphalan and prednisolone therapy may achieve remission with few side effects in dogs with CLL.

Animals↗
PubMed2004

Profiling analysis of differential gene expression between hematogenous and peritoneal metastatic sublines of human pancreatic cancer using a DNA chip.

We established the novel sublines HPC-1H5, HPC-3H4, HPC-4H4, and Panc-1H5, which have a high potential of liver metastasis, and HPC-1P5a, HPC-3P4a, HPC-4P4a, and Panc-1P5a, which have a high potential of peritoneal dissemination, derived from low metastatic HPC-1, HPC-3, HPC-4, and Panc-1cell lines, respectively. To clarify the molecular mechanisms of cancer metastasis and of the different levels of gene expression in a variety of metastatic potentials in pancreatic cancer, we performed a broad analysis of differential gene expression analysis between parental cell lines and metastatic sublines. In comparison with the parental cell lines, 65 and 36 genes were overexpressed and underexpressed in highly liver-metastatic sublines. On the other hand, 43 and 45 genes were overexpressed and underexpressed in highly peritoneal-metastatic sublines. uPAR and Serin protease were overexpressed, and E2A and IGF1R were underexpressed in both metastatic sublines. Hierarchical clustering analysis revealed 22 genes classifying liver, peritoneal metastatic sublines and low-metastatic parental cell lines. These genes might be targeted genes separating those two major metastatic forms after surgery. A greater number of cell line samples and more genes will have to be utilized in future studies in order to understand the involvement of genes in cancer metastasis more thoroughly. However, these results will help to clarify the molecular mechanisms of pancreatic cancer metastasis.

Cell Line, Tumor↗
PubMed2003

Quantitative analysis of Fas and Fas ligand mRNAs in a feline T-lymphoid cell line after infection with feline immunodeficiency virus and primary peripheral blood mononuclear cells obtained from cats infected with the virus.

Apoptosis is frequently observed in feline lymphocytes in association with feline immunodeficiency virus (FIV) infection. In this study, to investigate the mechanism of FIV-induced apoptosis, levels of Fas and Fas ligand mRNAs were measured by real-time reverse transcription-PCR. In a feline T-lymphoid cell line the amounts of Fas ligand mRNA increased along with the induction of apoptosis after in vitro infection with FIV. In PBMC collected from 10 cats naturally infected with FIV, Fas ligand mRNA levels were significantly higher than those in PBMC from five uninfected cats. These results indicate that the increased expression of Fas ligand may be involved in the induction of apoptosis of lymphocytes in FIV infection.

Animals↗
PubMed2003

PET neuroreceptor imaging as predictor of severe cerebral ischemic insult.

Measurement of the adenosine A1 receptor (A1-R) with positron emission tomography (PET) using a newly developed positron ligand, [1-methyl-11C]8-dicyclopropylmethyl-1-methyl-3-propylxanthine (MPDX). were performed in a cat middle cerebral artery (MCA) occlusion and reperfusion. Eighteen adult cats underwent PET measurement of; 1) cerebral blood flow (CBF). 2) A1-R, 3) central benzodiazepine receptor (BDZ-R) and 4) glucose metabolism with 15O labeled water, MPDX, 11C-flumazenil (FMZ) and 18F-fluorodeoxyglucose (FDG), respectively. The CBF, A1-R, BDZ-R and FDG uptake were serially measured after 60 min occlusion of MCA in this order. MPDX binding and FMZ binding, but not CBF and FDG uptake, were significantly reduced in the groups with severer ischemic insult than in the groups with no or milder insults. Of the two receptor ligands, the reduction rate of the MPDX binding to A1-Rs was larger in a group that caused fatal ischemic insult. The newly developed PET in vivo imaging technique using MPDX was suitable in evaluating the function of adenosine and A1-Rs in relation to cerebral ischemia.

Animals↗