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Biomedical subjects

Y Tsuchiya

Publications and source records attributed to Y Tsuchiya.

At least 55 records · Page 3Linked to original sources

Effects of chlorine, iodine, and quaternary ammonium compound disinfectants on several exotic disease viruses.

The effects of three representative disinfectants, chlorine (sodium hypochlorite), iodine (potassium tetraglicine triiodide), and quaternary ammonium compound (didecyldimethylammonium chloride), on several exotic disease viruses were examined. The viruses used were four enveloped viruses (vesicular stomatitis virus, African swine fever virus, equine viral arteritis virus, and porcine reproductive and respiratory syndrome virus) and two non-enveloped viruses (swine vesicular disease virus (SVDV) and African horse sickness virus (AHSV)). Chlorine was effective against all viruses except SVDV at concentrations of 0.03% to 0.0075%, and a dose response was observed. Iodine was very effective against all viruses at concentrations of 0.015% to 0.0075%, but a dose response was not observed. Quaternary ammonium compound was very effective in low concentration of 0.003% against four enveloped viruses and AHSV, but it was only effective against SVDV with 0.05% NaOH. Electron microscopic observation revealed the probable mechanism of each disinfectant. Chlorine caused complete degeneration of the viral particles and also destroyed the nucleic acid of the viruses. Iodine destroyed mainly the inner components including nucleic acid of the viruses. Quaternary ammonium compound induced detachment of the envelope of the enveloped viruses and formation of micelle in non-enveloped viruses. According to these results, chlorine and iodine disinfectants were quite effective against most of the viruses used at adequately high concentration. The effective concentration of quaternary ammonium compound was the lowest among the disinfectants examined.

African Horse Sickness↗

Thyroid hypertrophic effect of semotiadil fumarate, a new calcium antagonist, in rats.

We studied the effects of semotiadil fumarate (SF), a new calcium antagonist with a unique benzothiazine structure, on the thyroid gland and liver in rats and compared them with those of another calcium antagonist, nicardipine (NCD), a well-known thyroidal hypertrophic agent and microsomal enzyme inducer, phenobarbital (PB), and goitrogen propylthiouracil (PTU). In oral 2-week treatment, SF caused increases in hepatic microsomal protein levels, uridine diphosphate glucuronosyltransferase (UDPGT) activity and an increase in serum thyroid stimulating hormone (TSH) level together with decreases in serum thyroid hormone levels. These results suggest that SF accelerates peripheral disposition of thyroid hormones and subsequently stimulates secretion of TSH from the pituitary gland as a compensatory response. PB and NCD had similar effects on the thyroid gland and the liver. PTU showed obvious thyroid hyperplasia and an increase in relative liver weight. Drastic increase in TSH level was observed in the PTU-treated group together with significant decreases in serum thyroid hormone levels and an increase in hepatic UDPGT activity. Histopathologically, PTU depleted the colloids in follicles, suggesting the inhibition of thyroid hormone synthesis. SF, PB and NCD showed thyroidal hyperplasia, but the extent of the change was far more moderate than that induced by PTU. These results indicate that the effect of SF is similar to those of PB and thyroid hypertrophy seen in the oral 2-week treatment with SF, and may be caused by indirectly elevated TSH levels which resulted from the induction of hepatic UDPGT activity.

Animals↗

[The three-dimensional CT angiography findings of ruptured aneurysms hardly detectable by repeated cerebral angiography].

We reported three cases of cerebral aneurysms hardly detectable by cerebral angiography, but easily detected by three-dimensional CT angiography (3D-CTA). These cases were ruptured aneurysms with subarachnoid hemorrhage. After detection of subarachnoid hemorrhage on CT scan, cerebral angiography was performed at first, but aneurysms were not detected. Subsequently 3D-CTA was carried out, and aneurysms were detected. In all cases, cerebral angiography was repeated, after the aneurysms had been found by 3D-CTA. This time aneurysms were all detected by cerebral angiography, but each case needed photographs from special direction. The aneurysms were small by usual cerebral angiography and they were almost invisible behind the artery near which they existed. 3D-CTA was very useful for detection of small aneurysms, but small perforating arteries around the aneurysms were invisible by 3D-CTA. To find these perforating arteries, cerebral angiography was needed.

Aged↗

[A patient with advanced gastric cancer who obtained downstaging and underwent radical surgery by neoadjuvant chemotherapy].

The patient was a 74-year-old man with extremely advanced gastric cancer. A CT scan of the abdomen showed enlargement of many huge abdominal para-aortic lymph nodes. Neoadjuvant chemotherapy (NAC) was planned in order to reduce or eliminate the tumor. Two cycles of FLP combination therapy (5-fluorouracil, leucovorin, cisplatin) were given. After NAC, a CT scan revealed marked shrinkage of the No. 16 lymph nodes, and a distal gastrectomy with extended radical lymph node dissection including the No. 16 nodes was performed. The histological effect was judged to be grade 2. There were no viable cancer cells in the No. 16 lymph nodes. The FLP combination therapy as NAC was so effective that it induced downstaging from stage IVb to IIIb.

Adenocarcinoma↗

Afferent mechanisms of acute responses of renal sympathetic nerve activity to microgravity.

Exposure to microgravity is thought to induce an alteration of autonomic function through several afferent pathways. First, a removal of all hydrostatic gradients, which results in a large cephalad fluid shift. The fluid shift may induce an increase in transmural pressure in the cardiopulmonary region, which stimulates cardiopulmonary mechanoreceptors and baroreceptors, and elicits neurogenic responses. Secondly, an alteration of the vestibular input may modify sympathetic output via the vestibulosympathetic reflex. However, there is a lack of direct evidence for the role of cardiopulmonary mechanoreceptors, baroreceptors, and vestibular system in autonomic responses to microgravity. Accordingly, responses of renal sympathetic nerve activity (RNA) to microgravity, produced by free drop, were examined in anesthetized rats. To examine the afferent pathways of the RNA responses, the same experiment was performed in rats that had undergone labyrinthectomy, sinoaortic baroreceptor denervation (SAD), vagotomy, or SAD plus vagotomy.

Afferent Pathways↗

The novel neuropeptide Y Y(1) receptor antagonist J-104870: a potent feeding suppressant with oral bioavailability.

Neuropeptide Y (NPY) is known to induce robust feeding through the action of NPY receptors in the hypothalamus. Among the subtypes of NPY receptors, Y(1) receptors may play a key role in feeding regulation. In the present study, we demonstrated that a novel Y(1) antagonist, J-104870, shows high selectivity and potency for the Y(1) receptor with an anorexigenic effect on NPY-mediated feeding. J-104870 displaced [(125)I]peptide YY (PYY) binding to cloned human and rat Y(1) receptors with K(i) values of 0.29 and 0.54 nM, respectively, and inhibited the NPY (10 nM)-induced increase in intracellular calcium levels (IC(50) = 3.2 nM) in cells expressing human Y(1) receptors. In contrast, J-104870 showed low affinities for human Y(2) (K(i) > 10 microM), Y(4) (K(i) > 10 microM), and Y(5) receptors (K(i) = 6 microM). In rat hypothalamic membranes, J-104870 also completely displaced the binding of [(125)I]1229U91, which is known to bind to the typical Y(1) receptor, with a high affinity (K(i) = 2.0 nM). Intracerebroventricular (ICV) injection of J-104870 (200 microg) significantly suppressed NPY (5 microg)-induced feeding in satiated Sprague-Dawley rats by 74%. Furthermore, ICV and oral administration of J-104870 (200 microg and 100 mg/kg, respectively) significantly suppressed spontaneous food intake in Zucker fatty rats. These findings suggested that J-104870 is a selective and potent nonpeptide Y(1) antagonist with oral bioavailability and brain penetrability. In addition, the anorexigenic effect of J-104870 clearly revealed the participation of the Y(1) receptor in NPY-mediated feeding regulation. The potent and orally active Y(1) antagonist J-104970 is a useful tool for elucidating the physiological roles of NPY in obesity.

Administration, Oral↗

Double cancer of the gallbladder and common bile duct associated with an anomalous pancreaticobiliary ductal junction without a choledochal cyst: report of a case.

We report herein the case of a 37-year-old woman found to have double cancer of the gallbladder and common bile duct associated with an anomalous pancreaticobiliary ductal junction (APBDJ) without a choledochal cyst (CC). Abdominal ultrasonography showed an isoechoic mass in the gallbladder, and percutaneous transhepatic biliary drainage tubography revealed incomplete obstruction in the upper portion of the common bile duct and APBDJ. The patient underwent cholecystectomy, partial hepatic resection, pancreatoduodenectomy, and portal vein reconstruction. Pathological examination of the tumors from the gallbladder and bile duct revealed papillary carcinoma and poorly differentiated adenocarcinoma, respectively, and direct continuity was not observed between the tumors. A review of the literature on six cases of multiple primary carcinoma of the biliary tract associated with APBDJ without CC is presented following this case report. Double cancer of the biliary tract was found synchronously in five patients and metachronously in one. Gallbladder cancer showed subserosal invasion in four patients, while bile duct cancer invaded the pancreas in one patient and reached the serosa in two patients. Considering the potential for cancer to arise in the biliary tract and the difficulties associated with monitoring it, cholecystectomy and resection of the extrahepatic common bile duct may be the most appropriate treatment for patients with an APBDJ without a CC.

Adenocarcinoma↗

Serum level of cytokeratin 19 fragment (CYFRA 21-1) indicates tumour stage and prognosis of squamous cell carcinoma of the oesophagus.

To determine the clinical efficacy of serum concentration of cytokeratin 19 fragment (CYFRA 21-1), sera from 66 patients with oesophageal squamous cell carcinoma were examined, and 54 surgically resected specimens were immunohistochemically stained for cytokeratin 19 (CK-19). The patients with positive CK-19 staining in the tissues of their carcinomas had significantly higher serum CYFRA 21-1 levels compared with those with negative CK-19 staining. When the cut-off value was defined as 2.0 ng/mL, CYFRA 21-1 had a higher positive ratio than that of either squamous cell carcinoma antigen (SCC-Ag) or carcinoembryonic antigen (CEA). Serum CYFRA 21-1 level increased significantly along with the clinical stages. In addition, serum CYFRA 21-1 level served as a prognostic factor for patients with oesophageal carcinoma after surgery, whilst SSC-Ag and CEA is not connected with the outcome. These findings suggest that the serum CYFRA 21-1 probably originated from the tumour tissue is an important marker for determining the stage and outcome of oesophageal carcinoma.

Adult↗

Emerin and cardiomyopathy in Emery-Dreifuss muscular dystrophy.

Emery-Dreifuss muscular dystrophy (EDMD) is an inherited disorder characterized by the clinical triad of life-threatening progressive cardiomyopathy with conduction defect, early onset joint contractures and slow progressive muscle weakness in scapulo-humero-peroneal distribution. Cardiomyopathy in EDMD is usually noticed after the second to third decade of life, and becomes worse with age. Permanent auricular paralysis occurs frequently and is considered a hallmark of EDMD cardiomyopathy. Cardiac involvement may also occur in female carriers. In autopsy cases, enlargement of the atria with remarkable thinning have been observed. Identification of the gene responsible for X-linked EDMD (X-EDMD) and the protein product, emerin, provided a diagnostic clue for EDMD. Since the emerin gene is rather small, the entire sequence can easily be surveyed. Western blot and immunohistochemistry show an absence of emerin in muscle and skin tissues and oral exfoliating cells in male patients with X-EDMD, and a reduction of the protein content with a mosaic expression pattern in female carriers. Emerin anchors at the inner nuclear membrane of cardiac, skeletal and smooth muscles, and interacts with lamins and nucleoplasm, thereby possibly maintaining the mechanical stability of the nuclear membrane of muscle cells that shows rigorous contraction/relaxation. More recently, positive emerin staining at the cardiac demosomes and fasciae adherentes was noticed in addition to the specific localization at the inner nuclear membrane. This localization implies a physiological role for the protein in cardiac conduction.

Cardiomyopathies↗

J-104129, a novel muscarinic M3 receptor antagonist with high selectivity for M3 over M2 receptors.

A new class of 4-acetamidopiperidine derivatives has been synthesized and investigated for human muscarinic receptor subtype selectivity. Introduction of a hydrocarbon chain of appropriate length into the piperidine nitrogen of the racemic N-(piperidin-4-yl)-2-cyclobutyl-2-hydroxy-2-phenylacetamide platform conferred up to 70-fold selectivity for human muscarinic M3 receptors over M2 receptors. Subsequent synthetic derivatizations resulted in highly potent M3 receptor antagonists with selectivity greater than two orders of magnitude for M3 over M2 receptors, from which the analogue 4r was selected. Preparation of both enantiomers of 4r led to the identification of (2R)-N-[1-(4-methyl-3-pentenyl)piperidin-4-yl]-2-cyclopentyl-2-hyd roxy-2-phenylacetamide (J-104129, (R)-4r), which exhibited 120-fold selectivity for M3 receptors (Ki = 4.2 nM) over M2 receptors (Ki = 490 nM). In isolated rat trachea, (R)-4r potently and specifically antagonized acetylcholine (ACh)-induced responses with a K(B) value of 3.3 nM. The highly subtype-selective profile was also seen in isolated rat tissue assays (50-fold) and in anesthetized rats (> 250-fold). Oral administration of J-104129 ((R)-4r) antagonized ACh-induced bronchoconstriction with an ED50 value of 0.58 mg/kg in rats. Thus, J-104129 ((R)-4r) may effectively facilitate bronchodilation in the treatment of obstructive airway disease.

Alkenes↗

Distinct regions specify the nuclear membrane targeting of emerin, the responsible protein for Emery-Dreifuss muscular dystrophy.

Emery-Dreifuss muscular dystrophy is a neuromuscular disorder that has three characteristics: (a) early contracture of the elbows, Achilles tendons and postcervical muscles; (b) slowly progressive wasting and weakness of skeletal muscle; and (c) cardiomyopathy with severe conduction block. The responsible gene for the X-linked recessive form of this disease encodes an inner nuclear membrane protein named emerin. Although emerin is absent in tissues from patients with this disorder, it remains obscure why the loss of this widely expressed protein affects selectively skeletal muscle, heart and joints. As the first step to address this question, we examined the molecular regions of emerin that are essential for nuclear membrane targeting and stability of the protein. We found that the C-terminal hydrophobic region was necessary, but not sufficient, for nuclear membrane anchoring and stability of the protein. In the absence of this transmembrane domain, the upstream nucleoplasmic domain showed no firm association with the nuclear rim, but showed the tendency to accumulate at the nucleolus-like structures. Furthermore, proper targeting of emerin to the nuclear membrane required the latter half of the nucleoplasmic domain. These characteristics are distinct from those of lamina-associated polypeptide 2. Our findings indicate that emerin has distinct interactions with the inner nuclear membrane components that may be required for the stability and function of rigorously moving nuclei in tissues such as skeletal muscle, heart and joints.

Cell Line↗

The effects of a high dose, short course of interferon on hepatitis C.

To shorten the period of interferon (IFN) treatment for chronic hepatitis C, we investigated the clinical efficacy of a regimen using a higher dose and a shorter treatment period. Fifty chronic hepatitis C patients who were hepatitis C virus (HCV)-RNA positive and who were histologically diagnosed as having chronic hepatitis, took part in the study. Virus levels were measured before and 2 weeks after starting the treatment. We administered natural IFNalpha, 10 MU, i.m. daily for 2 consecutive weeks and then three times per week for the subsequent 14 weeks (total dose 560 MU). Patients who were HCV-RNA negative at the completion of the therapy and 6 months later, were evaluated as sustained responders (SR; 32%). Those who were not HCV-RNA negative at the two time points were evaluated as non-responders. Nucleotide and clone differences in the hypervariable region (HVR) and predictive factors for prognosis were also analysed. Low virus level and HCV-RNA genotype 2a/2b were the predictors for good prognosis, whereas the numbers of nucleotide differences and clone differences in HVR were not. Sustained responder patients became HCV-RNA negative 2 weeks after starting the treatment at a significantly higher rate, whereas no non-responder patients were HCV-RNA negative at that time. The SR rate (32%) was equivalent to those reported in previous 24 week treatment studies. This IFN therapy using a higher dose and a shorter period was useful.

Adult↗

Purification and further characterization of enteropeptidase from porcine duodenum.

Enteropeptidase [EC 3.4.21.9] is a membrane-bound serine endopeptidase present in the duodenum that converts trypsinogen to trypsin. We previously cloned the cDNA of the porcine enzyme and deduced its entire amino acid sequence [M. Matsushima et al. (1994) J. Biol. Chem. 269, 19976-19982]. In the present study, we purified the porcine enzyme approximately 2,200-fold in a 12% yield from a duodenal mucosal extract to apparent homogeneity by an improved procedure comprising four steps of chromatography including benzamidine-Sepharose affinity chromatography. Lectin blotting analysis suggested that the enzyme is glycosylated mainly with N-linked carbohydrate chains of the tri- and/or tetraantennary complex type. The H and L chains of the enzyme were separated into two major bands upon SDS-PAGE under reducing conditions, suggesting that the enzyme mainly comprises two isoforms, a higher molecular weight form and a lower molecular weight form. The enzyme was also separated by lectin affinity chromatography into two major fractions, named isoforms I and II, which corresponded to the higher and lower molecular weight forms, respectively. These two isoforms appeared to be different only in the carbohydrate moiety, having essentially the same enzymatic properties. The enzyme was optimally active at pH 8.0 toward Gly-Asp-Asp-Asp-Asp-Lys-beta-naphthylamide, and was inhibited strongly by various serine proteinase inhibitors. Furthermore, it was also strongly inhibited by E-64 [L-trans-epoxysuccinyl-leucylamide-(4-guanido)-butane], a cysteine proteinase inhibitor. Substrate specificity studies involving various synthetic peptides indicated that acidic residues at the P2, P3, and/or P4 positions are especially favorable for maximal activity, but are not absolutely necessary, at least in the cases of peptide substrates.

Animals↗

Myocardial distribution and biotransformation in vitro and in vivo of nicorandil in rats, with special reference to mitochondria.

This study reports subcellular localization of nicorandil in the myocardium and metabolism in mitochondria after oral dosing of 3 mg/kg nicorandil to rats. In the in vitro experiments, nicorandil, which was incubated with tissue homogenates (liver, kidney, heart, and small intestine), was metabolized to its denitrated compound, SG-86, and unknown substances. In the absence of a NADPH-generating system in the heart, the metabolic activity existed only in the mitochondrial fraction, but not in cytosolic and microsomal fractions. In the presence of the system, the activity in the mitochondrial fraction became much higher. To examine subcellular distribution of nicorandil in the myocardium, [14C]nicorandil was orally given to rats. Fifteen minutes after oral dosing of 3 mg/kg [14C]nicorandil, of which myocardial concentration reached a peak, nicorandil and SG-86 were found in mitochondrial fractions as well as in cytosolic and microsomal ones of the heart. Electron-microscopic autoradiograms, 15 min after oral dosing of 3 mg/kg [3H]nicorandil to rats, also showed the existence of the silver grains (showing radioactivity) in mitochondria of the heart. We conclude that nicorandil given orally is distributed in mitochondria of the heart, being partly transformed into SG-86, and that the myocardial mitochondria may be a potential site of action of nicorandil, an opener of KATP channels, which have been demonstrated to be present in this subcellular particle.

Animals↗

Levels of soluble cell adhesion molecules in patients with angiographically defined coronary atherosclerosis.

Adhesion molecules on the endothelial cell membrane play an important role in the pathogenesis of atherosclerosis. Levels of soluble forms of cell adhesion molecules are reportedly elevated in patients with peripheral artery vessel disease and in patients with an atherosclerotic aorta. The present study investigated the association of serum levels of soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble intercellular adhesion molecule 1 (sICAM-1), and soluble P-selectin (sP-selectin) with coronary heart disease (CHD) and the extent of coronary atherosclerosis, and examined the influence of serum levels of lipids, lipoproteins and apolipoproteins (apo) in subjects with (n=52, M/F:43/9) and without (controls, n=40, M/F:25/15) angiographically proven coronary atherosclerosis. After controlling for age and gender, levels of sVCAM-1 (least squares mean +/- std error: 565+/-36 ng/ml vs 540+/-41 ng/ml, ns), sICAM-1 (261+/-17ng/ml vs 247+/-19ng/ml, ns), and sP-selectin (142+/-8ng/ml vs 149+/-10 ng/ml, ns) in patients with coronary atherosclerosis were not different from those in controls, as assessed by an analysis of covariance. After also adjusting for body mass index, hypertension, diabetes mellitus, and smoking by a multiple logistic function analysis, the association of sVCAM-1, sICAM-1, and sP-selectin with CHD was still not significant. Levels of sVCAM-1, sICAM-1, and sP-selectin were also not related to the extent of coronary atherosclerosis as judged by the number of stenosed vessels. However, inverse (p<0.05) relationships were observed between sVCAMs and serum levels of HDL3-cholesterol, apo A-II, and lipoprotein containing apo A-I and A-II, between sICAMs and levels of apo A-II and Lp A-I/A-II (Lp A-I/A-II), and between sP-selectin and lipoprotein containing only apo A-I. In conclusion, serum levels of soluble VCAM-1, ICAM-1, and P-selectin were not related to CHD or the extent of coronary atherosclerosis, but were inversely related to serum levels of high-density lipoprotein-related lipoproteins.

Apolipoproteins↗

Electron microscopic autoradiography: an improved procedure using Aclar film and Grid-sticks.

A simple, time saving technique for electron microscopic autoradiography (EMARG) has been developed using both Aclar film and Grid-sticks. Rats were given 3 mg/kg [pyridine5-3H] nicorandil orally. After 15 min, animals were sacrificed, the hearts were removed, and myocardial samples for EMARG were prepared. Silver grains were detected clearly in myofibrils and in mitochondria, all showing well preserved ultrastructure. The use of Grid-sticks in the procedure improves handling of bulk samples.

Animals↗

[Effects of intravenous and oral administration of ondansetron hydrochloride on chemotherapy-induced nausea and vomiting in patients with esophageal cancer].

The effects of ondansetron hydrochloride (OND) were studied through 11 courses of chemotherapy, including 70 mg/m2 of cisplatin, in 9 patients with advanced esophageal cancer. During the observation period of 5 days, 4 mg of OND was given intravenously on the day of cisplatin infusion and orally for consecutive 4 days, and nausea was controlled by over 70%. Vomiting was controlled by over 80%. The inhibitory effect of OND on nausea and vomiting was found in 72.7% on the day of cisplatin injection and 88.9% overall. No other side effects of OND except slight increases in total bilirubin and LDH were found in any patient. These findings suggest that intravenous and oral administration of OND may inhibit chemotherapy-induced nausea and vomiting in patients with advanced esophageal cancer.

Administration, Oral↗