Publications by authors named "Hiyama T"

In this study, based on the data from FIV screening surveys of captive cats conducted by the Kyushu Veterinary Union and collaborators as part of the infection control program for Tsushima leopard cats (Prionailurus bengalensis euptilurus), we elucidated the spatial distribution of FIV-positive individuals among leopard cats and domestic cats using a geographic information system. Data from FIV screening surveys carried out among 86 leopard cats (1996-2006) and 713 captive domestic cats (2001-2006) were used for analysis. The analysis results were then spatially layered with the population density of leopard cats and that of captive domestic cats estimated from the number of households and used for assessment of FIV infection risk in each area.

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Background: The presence of multiple Lugol-voiding lesions (LVLs) in the esophageal mucosa can indicate a high risk of esophageal squamous cell carcinoma (ESCC) as well as a diagnosis of ESCC and dysplasia. However, there have been no reports on the natural course of LVLs.

Aim: This study aimed to clarify the characteristics and natural course of LVLs.

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We produced continuous records of sea surface salinity and isotopic composition from 1998 to 2004 at Ishigaki Island, southwest Japan, and found clear seasonal variations in salinity and oxygen isotopic composition and increasing trends of them after 1999. These increasing trends could be principally due to the decreasing difference between local precipitation (P) and evaporation (E), as a result of the reduction of horizontal vapour transport from adjacent oceans. When samples collected in heavy rainfall events were excluded, the average Deltadelta(18)O/Delta salinity slope was obtained as 0.

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In dehydrated animals, the antidiuretic hormone vasopressin (VP) is released from the nerve terminals of magnocellular neurons of the supraoptic nucleus (SON) and paraventricular nucleus (PVN) into the systemic circulation at the posterior pituitary. Increases in sodium (Na+)-level and osmolality in body fluids upon dehydration are reportedly sensed by a Na+-sensor and/or an osmosensor, respectively. However, it is still unknown whether both are involved in the regulation of production and/or release of VP.

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A 50-year-old man presented with a dissecting aneurysm arising from the extracranial portion of the right posterior inferior cerebellar artery (PICA) causing subarachnoid hemorrhage (SAH) and manifesting as sudden onset of disturbed consciousness. Computed tomography showed SAH with ventricular reflux predominantly in the posterior fossa. Angiography revealed a fusiform aneurysm of the right PICA originating extracranially from the right vertebral artery.

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Regioselective alkenylation and alkylation of 2-pyridone derivatives are achieved through inter- and intramolecular insertion of alkynes, 1,3-dienes, and alkenes into the C(6)-H bond by nickel/AlMe(3) catalysis. Coordination of the heterocycles to the Lewis acid cocatalyst through their basic carbonyl oxygen is considered to be responsible for the regioselective activation of the C-H bonds, probably through oxidative addition to nickel(0).

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A patient showing abnormal fluorine-18-fluorodeoxyglucose (FDG) uptake due to disseminated Mycobacterium avium complex (MAC) infection is presented. Increased focal FDG uptake was demonstrated in the cervical and supraclavicular lymph nodes, spleen, and diffuse bone marrow. FDG PET/CT is considered as a useful diagnostic tool to assess the exact extent and activity of disseminated MAC infection.

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Background: The relationship between esophageal squamous cell carcinoma (ESCC) and Lugol-voiding lesions (LVLs) in patients with head and neck squamous cell carcinoma (HNSCC) is unclear.

Aim: To investigate the characteristics of ESCC and the relationship between ESCC and LVLs in patients with HNSCC.

Methods: Between 2003 and 2006, 157 patients with primary HNSCC underwent Lugol chromoendoscopy at the Hiroshima University Hospital, Hiroshima, Japan.

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Allyl cyanides are found to add across alkynes in the presence of a nickel/P(4-CF(3)-C(6)H(4))(3) catalyst to give polysubstituted 2,5-hexadienenitriles with defined stereo- and regiochemistry. Use of AlMe(2)Cl or AlMe(3) as a Lewis acid cocatalyst accelerates the reaction and expands the substrate scope significantly. The cyano group in the allylcyanation products can be transformed to a hydroxymethyl or aminomethyl group to afford highly substituted allylic alcohols or amines.

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Background: A lack of published data remains on factors associated with the treatment response to proton pump inhibitors (PPI) in patients with non-erosive reflux disease (NERD).

Methods: Studies on effectiveness of PPI in patients with NERD were identified using the MEDLINE database and manual searches of the available literature. Twenty publications that comprised a total of 22 study arms were eligible, and meta-analyses of these 22 study arms were carried out.

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Nickel/Lewis acid dual catalysis was found to effect the carbocyanation reaction of alkynes using arylacetonitriles, giving a range of triply substituted acrylonitriles; the reaction of optically active alpha-phenylpropionitrile suggested a reaction mechanism that involves oxidative addition of a C-CN bond with retention of its absolute configuration.

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Background: Since trifluoromethyl-containing compounds have found diverse applications in the fields of pharmaceuticals and agrochemicals, facile and selective synthetic methods for trifluoromethyl-substituted compounds are an essential tool for advanced medicinal chemistry. Now that diverse synthetic transformations of carbon-carbon triple bonds are available, 3,3,3-trifluoropropynyl-substituted compounds serve as versatile building blocks for target molecules containing trifluoromethyl groups. Thus, novel synthetic methods and reagents for incorporation of a 3,3,3-trifluoropropynyl group into an organic compound have been the major concern in exploration and modification of fluorine-based biologically active substances.

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Eukaryotic translation initiation factor 2B (eIF2B) is the heteropentameric guanine-nucleotide exchange factor specific for eukaryotic initiation factor 2 (eIF2). Under stressed conditions, guanine-nucleotide exchange is strongly inhibited by the tight binding of phosphorylated eIF2 to eIF2B. Here, we report the crystal structure of the alpha subunit of human eIF2B at 2.

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Double Horner-Wadsworth-Emmons reaction of (E)-2,3-diaryl-1,4-bis(diethylphosphonyl)but-2-ene with (p-substituted) benzaldehydes gave (1E,3E,5E)-1,3,4,6-tetraarylhexa-1,3,5-trienes in moderate to good yields. Substitution of electron-withdrawing or -donating groups at the para position of the 1,6-diphenyl groups induced a slight bathochromic shift of UV spectra measured in CHCl(3) compared with that of the parent 1,3,4,6-tetraphenylhexa-1,3,5-triene. Although fluorescence was not observed with all the trienes in CHCl(3), they markedly emitted visible light in powder forms with quantum yields of 0.

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Palladium-catalyzed intramolecular direct arylation of 2-[(2-pyrrolyl)silyl]aryl triflates gives 3,2'-silicon-bridged 2-arylindoles and -pyrroles in good to high yields. The reaction proceeds through cleavage of C-OTf, C-Si, and C-H bonds to result in the formation of C-C and C-Si bonds. Various kinds of functional groups such as OMe, CN, Cl, F, and SiMe(3) tolerated the conditions.

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Cheilitis granulomatosa (CG) is a rare disease, which presents usually as a persistent swelling of the soft tissues in the orofacial region and is characterized histologically by a granulomatous inflammation. We report the case of a 19-year-old man who suffered from anal fistula. The patient had a 6-year history of asymptomatic and persistent swelling of the lower lip.

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The aim of this study was to clarify predictive factors for response to eradication therapy in cases of Helicobacter pylori (H. pylori)-positive API2-MALT1-negative gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Sixty-six patients who were examined for H.

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Cyanoformate esters add across 1,2-dienes in the presence of a nickel/PMe(2)Ph catalyst to afford beta-cyano-alpha-methylenealkanoates regioselectively, which are kinetically favored and readily isomerize to thermodynamically favored alpha-cyanomethyl-alpha,beta-unsaturated carboxylates at high temperature under the nickel catalysis, possibly through oxidative addition of the C-CN bond. Similar cyanoesterification products are produced from chloroformate esters, trimethylsilyl cyanide, and 1,2-dienes in the presence of a nickel/dppp catalyst. The resulting cyanoesterification products have a structure of allylic cyanide and thus undergo further allyl cyanation reaction across alkynes with the aid of a nickel/P(4-CF(3)-C(6)H(4))(3) catalyst to afford highly substituted acrylonitrile derivatives.

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Minimum requirements: Crystals and thin films of 1,4-bis(alkenyl)-2,5-dipiperidinobenzenes, which contain only one benzene ring as the aromatic component, emit visible light with excellent solid-state quantum yields upon irradiation with UV light. Polystyrene thin films doped with the benzenes also exhibit brilliant fluorescence. By modifying the alkenyl groups, the emission color can be tuned in the range from blue to red.

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Formamides are found to undergo addition reactions across alkynes and 1,3-dienes by nickel/Lewis acid catalysis to give a variety of alpha,beta- and beta,gamma-unsaturated amides with stereo- and regioselectivity. Intramolecular insertion reactions of olefins into the C-H bonds of formamides also proceed under similar conditions. The presence of Lewis acid cocatalysts is crucial, and formamide coordination to the Lewis acid is considered to be responsible for the activation of their formyl C-H bonds probably through oxidative addition to nickel(0).

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Background And Study Aims: Endoscopic mucosal resection (EMR) has been applied to the treatment of superficial esophageal squamous cell carcinoma (SCC). The incidence and characteristics of metachronous multiple esophageal SCCs and Lugol-voiding lesions (LVLs) were investigated in a retrospective study in patients who had undergone EMR for superficial esophageal SCC.

Patients And Methods: 96 patients with esophageal SCC who had been treated by EMR were followed up by endoscopy for 12 months or longer.

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An NADPH thioredoxin reductase C was co-purified with a 2-Cys peroxiredoxin by the combination of anion exchange chromatography and electroelution from gel slices after native PAGE from a thermophilic cyanobacterium Thermosynechococcus elongatus as an NAD(P)H oxidase complex induced by oxidative stress. The result provided a strong evidence that the NADPH thioredoxin reductase C interacts with the 2-Cys peroxiredoxin in vivo. An in vitro reconstitution assay with purified recombinant proteins revealed that both proteins were essential for an NADPH-dependent reduction of H2O2.

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