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Biomedical subjects

Y Horii

Publications and source records attributed to Y Horii.

At least 19 recordsLinked to original sources
PubMed2005

Clophen A60 composition and content of CBs, CNs, CDFs, and CDDs after 2D-HPLC, HRGC/LRMS, and HRGC/HRMS separation and quantification.

Chlorobiphenyl (CB) and by-side chlorodibenzofuran (CDF), chlorodibenzo-p-dioxin (CDD), and chloronaphthalene (CN) homologue group and congener composition, and concentrations have been examined in technical CBs mixture Clophen A60. 101 peaks representing 116 CB congeners were quantified in Clophen A60, and most contributing were CBs nos. 138, 153,134/144/149, and 180 with 15.4, 12.3,8.2, and 6.5%, respectively. Di-, tri-, tetra-, penta-, hexa-, hepta-, and octa-CBs constituted, respectively, 0.03, 0.03, 0.32, 9.9, 52.7, and 4.9% of chlorobiphenyls content of the Clophen A60, while mono-, nona-, and decaCB were not quantified. Tetra- to octaCDDs were absent in Clophen A60 at concentration above the method limit of quantification of <0.01 microg/g, while the total CDFs and CNs were found at 12 and 42 microg/g, respectively. Tetra-, penta-, hexa-, and hepta-CDF with 27, 46, 19, and 7% contribution, respectively, dominated in homologue group profile of CDFs, while octa-CDF was absent in Clophen A60. In compositional profile of CDF congeners the most abundant were 1,2,4,7,8-PeCDF, 2,3,4,7,8-PeCDF, and 1,2,3,4,7,8-HxCDF and each had >5% contribution. Amongst the CN homologue groups the profile in descending order followed by hepta-, hexa-, octa-, and penta-CNs with 56, 26, 16, and 2%, respectively. In compositional profile of CNs the most abundant were the congeners such as 1,2,3,4,5,6,7-HpCN (no. 73), 1,2,3,4,6,7-/1,2,3,5,6,7-HxCN (nos. 66/67), and 1,2,3,4,5,6,7,8-OcCN (no. 75) with 55, 21, and 16%, respectively. In terms of dioxin-like toxicity of Clophen A60 the contribution from planar non-ortho and mono-ortho CBs, CDFs, and CNs was 5280, 594.5, and 33.1 ng TCDD TEQ/g, respectively, and the total TEQ of planar analogues was 5908 ng/g.

Benzofurans↗
PubMed2004

Polychlorinated naphthalenes and polychlorinated biphenyls in benthic organisms of a Great Lakes food chain.

Invasion of zebra mussels, Dreissena polymorpha, and round gobies, Neogobius melanostomus, into the Great Lakes has altered the food web structure and thereby the pathways of toxic contaminants such as polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs). In this study, concentrations of PCNs and PCBs were measured in organisms of a Great Lakes benthic food chain encompassing zebra mussels. PCNs were found in all of the benthic organisms, including phytoplankton, algae, amphipods, zebra mussels, round goby, and smallmouth bass, Micropterus dolomieui. Concentrations of PCNs were greater in samples collected from the Raisin River than in samples from the St. Clair River. Biomagnification factors (BMF) for tetra- through octa-CN congeners in going from algae to zebra mussels from the St. Clair River ranged from 3 to 10. No major biomagnification of PCNs was found in round gobies, when concentrations were related to those in their prey species, zebra mussels. The biomagnification potential of PCNs appears to be similar to that of PCBs in the benthic food chain investigated in this study, despite the fact that PCNs may be metabolized by organisms higher in the food chain. Among several congeners, the BMFs of PCN congeners 35, 42, 43/45, 52/60, 58, and 66/67 were highest in round gobies. PCNs accounted for 1-22% of the total TEQs (toxic equivalents) of PCBs and PCNs in benthic organisms analyzed in this study. PCB congener 126 was the major contributor to TEQs, accounting for 72-99% of the PCB-TEQs in the food chain organisms analyzed.

Amphipoda↗
PubMed2004

Proliferation of protease-enriched mast cells in sarcoptic skin lesions of raccoon dogs.

Skin sites, tongue, lung, liver, jejunum and rectum from two raccoon dogs with Sarcoptes scabiei infestation and five normal (control) raccoon dogs were examined in terms of the distribution, proteoglycan properties and protease activity of mast cells. Infestation with S. scabiei caused a significant increase in the number of dermal mast cells. While the number of mast cells (average +/- standard deviation) in specimens of skin from the dorsum, dorsal neck, dorsal hind foot and dorsal fore foot was 40.0 +/- 19.8/mm2 in control animals, it was 236.1 +/- 58.9/mm2 in the skin of mange-infested animals. Histochemical analysis revealed the glycosaminoglycan, heparin, within the mast cells of all organs examined in both control and affected animals. Enzyme-histochemical detection of serine proteases demonstrated an increase in mast-cell-specific protease activity (i.e., chymase and tryptase) in the skin of infested animals. The percentage of mast cells demonstrating chymase activity was 53.0 +/- 27.4% in control animals and 73.8 +/- 19.4% in mite-infested animals. The corresponding results for tryptase activity were 53.5 +/- 25.2% and 89.4 +/- 9.8%. Increases in mast cell chymase or tryptase activity, or both, were also observed within other organs of the infected animals, but the total number of mast cells found at such sites (with the exception of liver and ventrolateral pinna) did not differ from those of control animals.

Animals↗
PubMed2004

Concentrations and fluxes of chloronaphthalenes in sediment from Lake Kitaura in Japan in past 15 centuries.

The concentrations of 63 congeners of chloronaphthalene (CN; polychlorinated naphthalenes, PCNs) in dated on approximately 500 B.C. to 2000 sediment core from the Lake Kitaura in Japan have been quantified by HRGC/HRMS after double column HPLC fractionation. Sediment from the Lake Kitaura showed a time-dependent pattern in distribution of CNs since the approximately 500 B.C. Starting from the 1910s the total CNs content increased accelerating from the 1960s, and, in parallel, the pattern of CN congeners has changed with a substantial increase in contribution from the penta, hexa, hepta, and octaCN. The total CNs content normalized to dry weight of sediment peaked out in the layer dated on 1984-1985, and next nearly two-fold decreased with further gradually decreasing concentration in 1987-2000. An occurrence of tri and tetraCNs in deep sediment layers corresponded to preindustrial synthesis and use of CNs seems to be connected to relatively greater water solubility and mobility in the pore water of those CN homologue groups. Based on CN congener pattern and results of multivariate analysis three main layers were separated in the sediment core. Starting from 1981 the emission sources related to combustion marker congeners become substantial contributors to flux of annually deposited CNs, while relative significance of the evaporative source marker congeners decreased after 1985. The annual flux of CNs into sediments of the Lake Kitaura was 0.073-0.31 pg/cm2 before 1926, increased to 5.5-14 pg/cm2 in 1963-1970 and next sharply increased to 50-107 pg/ cm2 in 1971-1985, and after that decreased to 17 pg/cm2 in 1997-2000.

Chlorine Compounds↗
PubMed2004

Pharmacokinetics of flunixin in the cat: enterohepatic circulation and active transport mechanism in the liver.

The plasma and urine pharmacokinetics of flunixin-meglumine (FNX) in cats were examined using a total of 12 adult animals. After an intravenous injection of FNX (2 mg/kg), the plasma concentration time curves showed a profile of a two-compartment open model with an elimination half-life of 6.6 h. In spite of high plasma protein binding (>99%), the V(d)beta was unusually large, 0.7 L/kg. Although the recovery of FNX from urine was only 0.4% of the dose, the estimated inherent renal clearance closely corresponded to the renal plasma flow rate, indicating that a renal active tubular secretion was involved in the pharmacokinetics of FNX. Cholestyramine (ChSA), an anion exchanger, was orally administered immediately before the FNX injection in order to determine the involvement of enterohepatic circulation in FNX pharmacokinetics. The elimination phase of the profile of FNX was prevented by the concomitant administration of ChSA, so it was concluded that the drug undergoes enterohepatic circulation in cats. Pravastatin (PV) is a specific substrate of the type-2 organic anion transporting polypeptide transporter (OATP-2) in human liver cells. The effect of a concomitant intravenous injection of PV with FNX was examined in order to determine the involvement of OATP-2 like transporter in the pharmacokinetics. The V1 and total body clearance were decreased after the injection of PV. In conclusion, at least two active transport mechanisms are involved in the pharmacokinetics of FNX in cats. One pathway is renal tubular secretion and the other is sinusoidal active uptake by liver cells. The latter may be responsible for the enterohepatic circulation of FNX in cats.

Animals↗
PubMed2004

Highly toxic chlorobiphenyl and by-side impurities content and composition of technical chlorofen formulation.

Non- and mono-ortho CBs as well as also highly toxic by-side impurities such as chlorodibenzofurans, chlorodibenzo-p-dioxins, and chloronaphthalenes after a subsequent 2D-HPLC and HRGC-HRMS separation, detection, and identification were quantified in technical chlorobiphenyl Chlorofen formulation. Chlorofen is highly chlorinated CB mixture and its compositional profile of mono-ortho CBs is occupied by 2,3,3',4,4',5'-HxCB (no. 157) with 96.6% and followed by 2,3,3',4,4',5-HxCB (no. 156) with 3.3% and 2,3',4,4',5,5'-HxCB (no. 167) with <0.1%, while nos. 105, 114, 118, 123, and 189 remained undetected (<10 microg/g). Amongst non-ortho CBs only a trace of 3,3',4,4'-TeCB (no. 77) was found at 15 microg/g, while CBs nos. 81, 126, and 169 were absent. TCDD TEQ for mono- and non-ortho CBs in Chlorofen was 2320 and 1.5 ng/g, respectively, while for CDFs and CNs were 45 and 731 ng/g, respectively, and for both types of contaminants most contributing were OcCDF and OcCN. No tetra- to OcCDD was found in Chlorofen.

Chemical Industry↗
PubMed2003

Feasibility study using a new small electronic pancreatoscope: description of findings in chronic pancreatitis.

BACKGROUND AND STUDY AIMS: Numerous images characteristic of chronic pancreatitis have been obtained with fiberoptic peroral pancreatoscopy systems. However, the resolution of these images is inferior to that obtained with peroral electronic pancreatoscopy (PEPS). Clearer images of the pancreatic duct with chronic pancreatitis have now been documented, in some cases using PEPS alone. The significance of this finding is reported here. PATIENTS AND METHODS: A total of 42 PEPS procedures were carried out in 36 patients with chronic pancreatitis, without sphincterotomy or balloon dilation of the papilla of Vater. Using endoscopic retrograde pancreatography, the patients were classified as having equivocal (n=5), mild (n=5), moderate (n=15), or marked (n=11) degrees of chronic pancreatitis. The insertion rate with PEPS was 90 % (38 of 42 procedures), and it was ultimately possible to examine five, three, 13, and 11 patients in each group, respectively. RESULTS: Images of turbid pancreatic juice, protein plugs of various shapes, pancreatic calculi, indistinct vascular markings, whitish mucosa, local redness, scattered redness, disappearance of the fold, deformation of the fold, irregularly dilated lumen, and stenosis were found to be characteristic of chronic pancreatitis. These images were obtained using PEPS. CONCLUSIONS: PEPS proved to be a feasible new technique for diagnosing chronic pancreatitis, and it was able to detect abnormal findings more clearly than other imaging methods.

Aged↗
PubMed2003

Polychlorinated naphthalene contamination of some recently manufactured industrial products and commercial goods in Japan.

A follow-up case study was performed after two incidents of recent illegal import and use in Japan both of technical PCNs mixture and contaminated with those compounds an industrial raw material. In case 1, above 18 tons of PCNs mixture, resembling Halowax 1001, which is a technical PCNs formulation, were imported from the United Kingdom. An illegally imported PCNs mixture was used for manufacture of a wide spectrum of industrial materials and commercial goods including sealants, putty, shock absorbing materials, adhesive materials, insulating materials and rubber belts. About 1.3 tons of PCNs contained in the Neoprene FB manufactured reached domestic market and 9.3 tons could reach other markets. In case 2, which became known in 2001, the Japanese company imported from Canada 54 tons of PCNs contaminated raw rubber material for industrial use. In weathering test (40 degrees C for up to 168 h) of the feral rubber coated sheets for rubber bands 98% of di- and 66% of tri-CNs vaporized. A loss rate of tetra-, penta-, and hexa-CN during initial 12 h of the weathering test ranged from approximately 10 to approximately 20%, while from 12 to 168 h remained negligible.

Chlorine Compounds↗
PubMed2001

Signaling pathway of ciliary neurotrophic factor in neuroblastoma cell lines.

BACKGROUND: Ciliary neurotrophic factor (CNTF) is a member of the interleukin-6 (IL-6) cytokine family and affects the survival and differentiation of several classes of neurons. For signal transduction, CNTF requires a receptor complex, composed of the IL-6 signal transducing molecule gp130, leukemia inhibitory factor receptor (LIFR)-beta, and CNTFR-alpha. There are two major independent pathways (Jak-STAT and Ras-MAPK) in cell signaling, and some recent reports show interaction between these pathways. The signal of the IL-6 family is mainly transduced to the Jak-STAT pathway through gp130. However, it has not been examined in neuroblastoma in detail. PROCEDURE AND RESULTS: Here we examine the signaling pathway of CNTF in 11 neuroblastoma cell lines. Northern blot analysis revealed that 3 of the 11 cell lines expressed c-fos mRNA after CNTF stimulation. Cell lysates were immunoprecipitated with agarose-conjugated antiphosphotyrosine antibody and blotted with anti-gp130, anti-Jak1, or anti-STAT3 antibody. Tyrosine phosphorylation of gp130, Jak1, and STAT3 was observed after CNTF stimulation in these three cell lines. Furthermore, tyrosine phosphorylation of ERK1 (one of the MAPKs) was also observed in all of them. CONCLUSIONS: These results demonstrate that CNTF signaling is conserved in some of the neuroblastoma cell lines and suggest that not only a Jak-STAT pathway but a MAPK pathway is activated by CNTF through gp130 in neuroblastoma cell lines.

Antigens, CD↗
PubMed2001

Recurrence of breast cancer following local excision alone for ductal carcinoma in situ.

OBJECTIVE: To assess recurrence of breast cancer following local excision alone for ductal carcinoma in situ. METHODS: Eighteen patients who received complete resection for noninvasive ductal carcinoma between 1982 and 1997 were investigated in this study. The mean age of the patients was 45 (29-78) years old. The initial presentation was a clinically palpable tumor in 4 patients, nipple discharge in 6, and microcalcification on mammograms in 8. Patients with palpable tumor underwent wide excision with at least a 2-cm free margin. Patients whose mammograms showed microcalcification underwent lumpectomy, and those who showed nipple discharge underwent duct-lobular segmentectomy. Five patients who underwent lymph node dissection up to level I or II had no lymph node metastasis. The mean follow-up period was 86 months. RESULTS: Local recurrence in the conserved breast was seen in five (27.8%) of 18 patients. The actuarial five-year event-free survival was 76.2%. The histological type of the recurrent tumor was ductal carcinoma in situ in three patients and invasive carcinoma in two. There was no difference in age at initial operation or histological subtype between patients with and without recurrent disease, but patients presenting with nipple discharge initially had a significantly shorter ipsilateral disease-free interval than those presenting with tumor or microcalcification on mammograms. All patients with local recurrence in the conserved breast were treated with breast-conserving surgery or subcutaneous mastectomy. CONCLUSION: Local recurrence frequently occurs in patients presenting with nipple discharge treated by duct-lobular segmentectomy for noninvasive ductal carcinoma. Either wide excision with a larger free margin or adjuvant radiation therapy following duct-lobular segmentectomy should be considered for these patients.

Adult↗
PubMed2001

Analysis of PTEN/MMAC1 alteration in neuroblastoma.

Neuroblastoma is the most common extracranial solid tumor in children. Although it has been reported that loss of heterozygosity at various loci, including 10q, frequently occurs in neuroblastoma, a bona fide tumor suppressor gene has not been identified. Recently, a gene mapped to chromosome 10q23, PTEN/MMAC1, was identified as a tumor suppressor gene that inhibits cell survival and cell proliferation by catalyzing the dephosphorylation of phosphatidylinositol 3,4,5-triphosphate. To screen for mutations of this gene in neuroblastoma, we analyzed 11 primary neuroblastoma tumors and 16 neuroblastoma cell lines for PTEN/MMAC1 mutations and deletions. All nine exons of the PTEN/MMAC1 gene were examined using the polymerase chain reaction-single strand conformational polymorphism assay and sequencing. Only one of the cell lines showed a mutation, a 1-bp frameshift deletion in exon 7, and an allelic loss in the opposite allele was revealed by a microsatellite analysis. Our results indicate that the disruption of the PTEN/MMAC1 gene is not a frequent event in neuroblastoma, and suggest that this disruption may be responsible for malignant progression in only a limited proportion of cases of neuroblastoma.

Alleles↗
PubMed2001

Ghrelin in domestic animals: distribution in stomach and its possible role.

Ghrelin, a novel growth-hormone-releasing acylated peptide, was recently isolated from rat and human stomachs. In rat, peripheral or central administration of ghrelin stimulates the secretion of growth hormone (GH) from the pituitary gland. Recent work suggests that ghrelin plays an important role in energy homeostasis, body weight, and food intake. We examined the distribution of cells immunoreactive to ghrelin in the stomachs of domestic animals and rats, using a polyclonal antibody for the N-terminal fragment of rat ghrelin [1-11]. We measured the plasma levels of ghrelin before and after feeding in cows, and GH levels after central administration of ghrelin in Shiba goats, to elucidate the possible role of ghrelin. Immunostained cells were widely distributed from the neck to the base of the oxyntic gland in all animals. The plasma ghrelin concentration in cows decreased significantly 1 h after feeding, and then recovered to pre-feeding levels. Administration of ghrelin into the third ventricle in Shiba goats dramatically increased the plasma GH concentration dose-dependently. These results suggest that ghrelin plays an important role in GH secretion and feeding regulation in domestic animals.

Animals↗
PubMed2001

Granular cell tumor of the urinary bladder.

A case of granular cell tumor of the urinary bladder is reported. A 48-year-old Japanese man with a bladder tumor underwent transurethral resection of the tumor and microscopic examination showed a granular cell tumor. Immunohistochemical staining for neuron specific enolase and S100 protein was positive, and it was suggested that the granular cell tumor was derived from Schwann cells.

Granular Cell Tumor↗
PubMed2001

Demonstration of chymotryptic and tryptic activities in mast cells of rodents: comparison of 17 species of the family Muridae.

On the basis of studies in laboratory rats, mast cells were originally classified into two subgroups, namely, mucosal mast cells (MMCs), which contained chymase, and connective tissue mast cells (CTMCs), which contained both tryptase and chymase. This classification has been applied to other animal species, despite the fact that the MMCs and CTMCs of such species sometimes consist of mixed populations of mast cells in terms of tryptase and chymase constitution. This report describes the protease constitution of mast cells in 17 species of nine genera (Acomys, Apodemus, Cricetulus, Meriones, Millardia, Mus, Rattus, Sigmodon and Vandeleuria) of the family Muridae. MMCs with negative tryptase activity were detected only in the intestinal mucosa of six subspecies of Mus musculus, two Rattus spp. and Vandeleuria oleacea, and only Apodemus sylvaticus possessed CTMCs with no tryptase activity. Since mast cells conforming to the conventional classification were observed only in three of the nine genera examined, we propose that mast cells of rodents of the family Muridae should be classified by their protease constitution rather than by their location.

Animals↗
PubMed2001

Signal transduction pathways through TRK-A and TRK-B receptors in human neuroblastoma cells.

Little is known about the signal transduction pathways of TRK family receptors in neuroblastoma (NB) cells. In this study, an NB cell line, designated MP-N-TS, was established from an adrenal tumor taken from a 2-year-old boy. This cell line expressed both TRK-A and TRK-B receptors, which is rare in a single NB cell line. Therefore, the MP-N-TS cell line was used to determine whether the signal transduction through these constitutive receptors is functional. Three neurotrophins, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin-4 / 5 (NT-4 / 5), induced tyrosine phosphorylation of panTRK, and BDNF and NT-4 / 5 induced tyrosine phosphorylation of TRK-B. Tyrosine phosphorylation of panTRK and / or TRK-B by the neurotrophins was inhibited in the presence of a tyrosine kinase inhibitor K252a. Tyrosine phosphorylation of Src homologous and collagen (Shc), extracellular signal-regulated kinase (ERK)-1 and ERK-2, and phospholipase C-gamma1 (PLC-gamma1) was increased by the three neurotrophins and the increase was inhibited in the presence of K252a. Activation of Ras, detected as the GTP-bound form of Ras, was induced by the three neurotrophins. The neurotrophins did not modulate the expressions of TRK-A or TRK-B mRNA, but they did induce the expression of c-fos mRNA. Exogenous NGF induced weak neurite outgrowth, whereas exogenous BDNF and NT-4 / 5 induced distinct neurite outgrowth. Exogenous BDNF and NT-4 / 5 increased the number of viable cells, while NGF did not. Our results demonstrate that the signal transduction pathways through TRK-A and TRK-B in MP-N-TS cells are functional and similar, and the main downstream signaling pathways from the three neurotrophins are mitogen-activated protein kinase (MAPK) cascades through Shc, activated Ras, ERK-1 and ERK-2, and the transduction pathway through PLC-gamma1. Further, BDNF and NT-4 / 5 increased cell viability. The MP-N-TS cell line should be useful for clarifying the TRK-A and TRK-B signaling pathways responsible for the different prognoses in patients with NB.

Adrenal Gland Neoplasms↗
PubMed2001

Myocardial inflammatory cell infiltrates in cases of dilated cardiomyopathy as a determinant of outcome following partial left ventriculectomy.

Partial left ventriculectomy (PLV) can be used to treat refractory congestive heart failure caused by dilated cardiomyopathy (DCM). In order to understand the relationship between the underlying myocardial injury and early clinical outcomes after PLV, histopathologic, immunohistochemical and virologic studies of the resected myocardium were performed. The posterolateral left ventricular walls from 27 patients with idiopathic DCM were examined. Cardiomyocyte diameter, degree of myocardial fibrosis, degree of cardiomyocyte degeneration, and degree of inflammatory cell infiltration were compared with mortality rates. Polymerase chain reaction was performed to detect enterovirus genome in the myocardium. Some patients had inflammatory cell infiltrates with focal accumulations of lymphocytes and macrophages, including both cytotoxic/suppressor T-cells and helper/inducer T-cells. The number of inflammatory cells (activated lymphocytes plus macrophages/mm2) was significantly greater in patients who died of cardiac insufficiency after surgery (27.8 +/- 5.7; n = 7) than in the survivors (11.1 +/- 2.5; n = 15). There was no significant difference in the degree of myocardial fibrosis, cardiomyocyte diameter or degree of cardiomyocyte degeneration between the 2 groups. Enterovirus genome was detected in the myocardium of 9 (38%) of 24 patients examined and 5 of these enterovirus-positive hearts had severe inflammatory cell infiltrates (37.9 +/- 2.5/mm2). Early survival in patients undergoing PLV for DCM is significantly affected by the degree of myocardial inflammation, so patients with more severe or ongoing inflammation may have poor clinical outcomes. Chronic myocarditis may play an important role in the etiology and pathophysiology of idiopathic DCM.

Adolescent↗
PubMed2001

Synthetic peptide-based electrochemiluminescence immunoassay for anti-Borna disease virus p40 and p24 antibodies in rat and horse serum.

Borna disease virus (BDV) is a neurotropic pathogen that infects a wide variety of vertebrates. We have developed a new electrochemiluminescence immunoassay (ECLIA) for the detection of antibodies to BDV, using three synthetic peptides corresponding to the amino acid residues 3-20 and 338-358 of p40 and 59-79 of p24 peptide of BDV. Using the ECLIA, we examined serum samples for the presence of anti-BDV antibodies in 20 rats (experimentally BDV-infected and uninfected) and 38 horses (13 US horses, experimentally infected and uninfected, and 25 Japanese horses, feral and domestic). The ECLIA, performed in a double-blind manner, detected anti-BDV antibodies in rats with a history of BDV infection, giving results that were in agreement with indirect immunofluorescence assay and/or Western blot (WB) analysis. The ECLIA also correctly identified all three experimentally infected horses and four domestic American horses that were seropositive for BDV antibodies by WB. Among the Japanese horses, at least two out of 10 feral and six out of 15 domestic horses were seropositive for BDV. In most of these cases, the specificity of immunoreactivity was verified by blocking with soluble p40 and p24 peptides.

Amino Acid Sequence↗