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S Kato

Publications and source records attributed to S Kato.

At least 163 records · Page 9Linked to original sources
PubMed2001

Protective effect of rebamipide on indomethacin-induced intestinal damage in rats.

BACKGROUND AND AIM: We evaluated the effect of rebamipide (2-(4-chlorobenzoylamino)-3-[2(1H)-quinolinon-4-yl] propionic acid), a novel anti-ulcer drug, on indomethacin-induced small intestinal lesions in rats. METHODS: The animals were administered indomethacin (10 mg/kg, s.c.), and they were killed 24 h later. Rebamipide (30-300 mg/kg) was administered p.o. twice, 30 min before, and 6 h after indomethacin. RESULTS: Indomethacin caused hemorrhagic lesions in the rat small intestine, accompanied by an increase in enterobacterial translocation, inducible nitric oxide synthase (iNOS) and myeloperoxidase (MPO) activities, as well as thiobarbituric acid (TBA) reactants, and these changes were significantly prevented by the supplementation with 16,16-dimethyl prostaglandin E2 (dmPGE2; 10 microg/kg, i.v.) or the pretreatment of animals with the antibiotic ampicillin. Treatment of the animals with rebamipide dose-dependently prevented the development of intestinal lesions, and this effect was mimicked by i.v. administration of superoxide dismutase (SOD: 3000 U/kg) + catalase (CAT: 5000 U/kg). The protection by rebamipide was accompanied by a significant suppression of the increase in both MPO and iNOS activities, and a complete inhibition of the increase in TBA reactants, while SOD + CAT significantly inhibited the increase of MPO activity and TBA reactants, but not iNOS activity. The bacterial translocation following indomethacin was also significantly decreased by either rebamipide or SOD + CAT. CONCLUSION: These results confirmed the importance of enterobacteria and iNOS/NO in the pathogenesis of indomethacin-induced small intestinal lesions, and suggested that rebamipide prevents the development of these lesions, probably by its radical scavenging action.

Alanine↗
PubMed2001

A Japanese herbal medicine, Sho-saiko-to, prevents gut ischemia/reperfusion-induced hepatic microvascular dysfunction in rats.

BACKGROUND AND AIM: We have reported that gut ischemia/reperfusion (I/R) causes hepatic microvascular dysfunction. Nitric oxide (NO) has been found to be a modulator of the adhesive interactions between leukocytes, platelets, and endothelial cells. Sho-saiko-to (TJ-9), a Japanese herbal medicine, is reported to have protective effects against liver injury and to regulate NO production. The objective of this study was to determine whether TJ-9 affects hepatic microvascular dysfunction elicited by gut I/R, and to investigate the role of NO. METHODS: Male Wistar rats were exposed to 30 min of gut ischemia followed by 60 min of reperfusion. Intravital microscopy was used to monitor leukocyte recruitment and the number of non-perfused sinusoids (NPS). Plasma tumor necrosis factor (TNF)-alpha and alanine aminotransferase (ALT) activities were measured. In another set of experiments, TJ-9 (1 g/kg per day intragastrically) was administered to rats for 7 days. In some experiments, dexamethasone (ST) (2 mg/kg per day intravenously) was administered. RESULTS: In control rats, gut I/R elicited increases in the number of stationary leukocytes, NPS, and plasma TNF-alpha and ALT activities, and these changes were mitigated by the pretreatment with TJ-9. Pretreatment with an NO synthase inhibitor diminished the protective effects of TJ-9 on the increase in leukostasis in the pericentral region, NPS, and plasma TNF-alpha levels, but not its effect on the increase in leukostasis in the midzonal region, total number of stationary leukocytes, or plasma ALT activities. Pretreatment with TJ-9 increased plasma nitrite/nitrate levels. The responses caused by gut I/R were attenuated by the pretreatment with ST. Pretreatment with an NO synthase inhibitor did not affect the effect of ST. CONCLUSIONS: These results suggest that TJ-9 attenuates the gut I/R-induced hepatic microvascular dysfunction and inflammatory responses such as TNF-alpha production in the early phase via enhancement of NO production, and sequential hepatocellular damage via its anti-inflammatory effect like corticosteroid effect.

Animals↗
PubMed2001

Formation of advanced glycation end-product-modified superoxide dismutase-1 (SOD1) is one of the mechanisms responsible for inclusions common to familial amyotrophic lateral sclerosis patients with SOD1 gene mutation, and transgenic mice expressing human SOD1 gene mutation.

Neuronal Lewy body-like hyaline inclusions (LBHI) and astrocytic hyaline inclusions (Ast-HI) are morphological hallmarks of certain familial amyotrophic lateral sclerosis (FALS) patients with superoxide dismutase-1 (SOD1) gene mutations, and transgenic mice expressing the human SOD1 gene mutation. The ultrastructure of inclusions in both diseases is identical: the essential common constituents are granule-coated fibrils approximately 15-25nm in diameter and granular materials. Detailed immunohistochemical analyses have shown that the essential common protein of the inclusions in both diseases is an SOD1 protein. This finding, together with the immunoelectron microscopy finding that the abnormal granule-coated fibrils comprising the inclusions are positive for SOD1, indicates that these granule-coated fibrils containing SOD1 are important evidence for mutant SOD1-linked disease in human and mouse. For immunoelectron microscopy, the granule-coated fibrils are modified by advanced glycation endproducts (AGE) such as N(epsilon)-carboxymethyl lysine, pyrraline and pentosidine (Maillard reaction). Based on the fact that AGE themselves are insoluble molecules with direct cytotoxic effects, the granule-coated fibrils and granular materials are not digested by the lysosomal and ubiquitin systems. The neurons and astrocytes of the normal individuals and non-transgenic mice show no significant immunoreactivity for AGE. Considered with the mutant-SOD1 aggregation toxicity, a portion of the SOD1 comprising both types of the inclusion is modified by the AGE, and the formation of the AGE-modified SOD1 (probably AGE-modified mutant SOD1) is one of the mechanisms responsible for the aggregation (i.e. granule-coated fibril formation).

Amyotrophic Lateral Sclerosis↗
PubMed2001

Panic disorder cases in Japanese-Brazilians in Japan: their ethnic and cultural confusion.

The comparatively high salaries made in Japan are attractive to many Japanese-Brazilians. The number of individuals from this ethnic group being treated in Japanese mental hospitals has increased. We hypothesized that Japanese-Brazilian patients with panic disorders adjusted better to Japanese society and culture than those with other mental disorders. The subjects in the present study are 40 Japanese-Brazilian patients undergoing treatment at the Department of Psychiatry at Jichi Medical School, Japan, from May 1990 to September 1998. Patients were divided into a panic disorder group, a schizophrenic group, a mood disorder group and a neurosis group. Demographic data (Japanese language ability, duration of residence in Japan etc.) were collected. A comparison was made among the four groups. Patients in the panic disorder group showed a significant tendency to be fluent speakers of Japanese. Patients in the panic disorder group also had been in Japan for a significantly longer period of time than those in the other three groups. Japanese ability and length of residence in Japan rule out exacerbating factors due to a foreign living environment. Panic disorder patients usually have resolved the problems inherent in living and working in a foreign country. In general, Japanese-Brazilians are more comfortable both financially and socially in Japan than other foreign laborers because of their cultural and family background. The emotional conflict experienced by such patients may result from concern over whether to live in Brazil or Japan in the future. Their ethnic and cultural identity may be confused, fluctuating between identifying with Brazil and with Japan, and this may cause vague feelings of anxiety.

Adult↗
PubMed2001

Pitch perception shift: a rare side-effect of carbamazepine.

Carbamazepine-induced pitch perception shifts have rarely been described. Two cases of shifted pitch perception developing during medication with carbamazepine are described. Case 1 possessed absolute pitch. Her pitch perception shift disappeared with the discontinuance of carbamazepine. Case 2 did not have absolute pitch. Even though he experienced a pitch perception shift, he developed a tolerance to the shift. We concluded that carbamazepine was the cause of the pitch perception shift in the first case, while the second case probably became attuned to the change in pitch perception because he did not possess absolute pitch.

Adolescent↗
PubMed2001

Expression of bone morphogenetic proteins in colon carcinoma with heterotopic ossification.

Here we report the case of a 50-year-old woman with adenocarcinoma of the colon, showing heterotopic ossification. The patient was referred to our hospital for investigation of anemia secondary to occult gastrointestinal blood loss. By colonoscopy, an irregular polypoid mass was found in the ascending colon. A biopsy of the lesion revealed moderately to poorly differentiated adenocarcinoma with heterotopic ossification. A right hemicolectomy was done and revealed areas of heterotopic bone within the tumor, but no ossification was evident in the metastatic lesions within the mesenteric lymph nodes. The formation of heterotopic bone in gastrointestinal tumors is rare and its exact mechanism is unknown. Immunohistochemical localization of bone morphogenetic proteins (BMP), known to be primary inducers of new bone formation, was determined. BMP-5 and -6 were prominent in the cytoplasm of tumor cells, and they stained weakly in osteoblast-like cells adjacent to newly formed bone. Cytoplasmic staining for BMP-2 and -4 was weak in tumor cells, osteoblast-like cells, and stromal fibroblast cells. BMP may play an important role in heterotopic ossification in colon adenocarcinoma.

Adenocarcinoma↗
PubMed2001

Non-neoplastic glandular structures in a benign peripheral nerve sheath tumor.

It is a recognized fact that glandular structures sometimes occur in peripheral nerve sheath tumors (PNST). Reports indicate that epithelial potential could be expressed in malignant PNST, while the glands in most benign PNST could be trapped skin adnexa. We present a case of spindle cell tumor with glandular structures. The patient was a 55-year-old man who had a subcutaneous tumor excised. The spindle cell tumor had histological characteristics of neurofibroma. The glandular structures had a pattern of immunohistochemical staining that was similar to that of the secretory coils and excretory ducts of normal eccrine glands. Therefore, the glands were thought to be naturally existing eccrine glands. The glands were completely enclosed within the tumor and not connected to one another; a cluster formation was not observed. The upper portion of tumor included some glands of skin adnexa. The spindle cell tumor may have originated from the nerves distributed around the skin adnexa, and grown to the subcutaneous tissue. The glands may have been left behind rather than have been trapped in the tumor.

Eccrine Glands↗
PubMed2001

A stone developed within the dilated intravesical ureter following ureteroscopy.

A 58-year-old man presented with a stone within the dilated intravesical ureter, which was probably attributable to a previous ureteroscopy. Transurethral incision of the right intravesical ureter and lithotripsy were carried out without subsequent urinary tract impairment. Although some complications resulting from ureteroscopy, such as ureteral stricture, ureteral perforation and vesicoureteral reflux, have been reported, this complication is considered to be very rare.

Humans↗
PubMed2001

Donor leukocyte infusion for Japanese patients with relapsed leukemia after allogeneic bone marrow transplantation: indications and dose escalation.

To clarify the role of dose escalation of donor leukocyte infusion (DLI) in the treatment of relapsed leukemia after allogeneic bone marrow transplant (BMT), data from 100 patients were collected from 46 facilities in Japan and analyzed with respect to indications and infused cell dose. Complete remission (CR) was achieved in 11 of 12 (91%) patients with relapsed chronic myelogenous leukemia (CML) in the chronic phase, 3 of 11 (27%) with CML in the acute phase, 8 of 21 (38%) with acute myelogenous leukemia (AML), 6 of 23 (25%) with acute lymphoblastic leukemia (ALL), and 5 of 11 (45%) with myelodysplastic syndrome (MDS). The probability of remaining in CR at 3 years was 82% in CML patients in the chronic phase, but 0% in those with CML in the acute phase, 7% in those with AML, 0% with ALL, and 33% with MDS. Acute graft-versus-host disease (GVHD) (> or = 2) developed in 31 of 89 (34%) patients with human leukocyte antigen identical related donors and was fatal for 7 (7%). A leukocyte dose of 1 x 10(7)/kg of recipient body weight with CML in the chronic phase, 3 x 10(7)/kg of recipient body weight with MDS, and 1 x 10(8)/kg of recipient body weight with acute leukemia appeared to be optimal as an initial dose of DLI. However, the minimal dose of leukocyte developing fatal GVHD was 7 x 10(7)/kg of recipient body weight. These suggest that a relatively small dose of DLI ranging from 1 x 10(7)/kg to 5 x 10(7)/kg of recipient body weight should be administered initially then the infused escalating dose 2 or 3 months later in patients with CML in the chronic phase and MDS. However, a large number of leukocytes around 1 x 10(8)/kg are needed to induce graft versus leukemia effects in patients with acute leukemia despite a 7% fatality in GVHD.

Adolescent↗
PubMed2001

Transcriptional activation of p21 by vitamin D(3) or vitamin K(2) leads to differentiation of p53-deficient MG-63 osteosarcoma cells.

p21 (WAF1/CIP1) is a downstream effector of p53 and mediates growth arrest by inhibiting the action of G(1) cyclin-dependent kinases. However, it has been reported that the p21 expression was triggered by multiple differentiation-inducing agents by a p53-independent pathway. These agents induced expression of p21 by binding to specific DNA elements and modulating transcriptional initiation. We demonstrated that the gene encoding p21 was not only a vitamin D(3) target gene but also a vitamin K(2) target gene in the cells and that their differentiation was well related to the transcriptional activation of the p21 gene. Transient overexpression of p21, using adenovirus-driven p21 expression plasmid, in MG-63 cells in the absence of vitamins D(3) and K(2) resulted in their differentiation. The transcriptional activation of p21 by vitamin D(3) or vitamin K(2) in p53-deficient osteosarcoma cells demonstrated the p53-independent role of p21 in human osseous differentiation. HUM PATHOL 32:410-416.

Bone Neoplasms↗
PubMed2001

Effects of nitric oxide donor and nitric oxide synthase inhibitor on ruminal contractions in conscious sheep.

The present study was planned to evaluate a role of nitric oxide (NO) in the regulation of regular ruminal contractions in conscious sheep. Intravenous infusion of S-nitroso-acetyl-DL-penicillamine (SNAP) at doses of 3-30 nmol kg(-1) min(-1)for 30 minutes inhibited both the amplitude and frequency of ruminal contractions in a dose-dependent manner. However, intravenous infusion of Nomega-nitro-L-arginine-methyl ester (L-NAME) at doses of 0.3-3.0 micromol kg(-1) min(-1)did not alter the basal tone of intraruminal pressure and the amplitude of ruminal contractions. The frequency of contractions was slightly inhibited by L-NAME infusion at 1.0 micromol kg(-1)min(-1). The effects of L-NAME were abolished by simultaneous infusion of L -arginine at 30 micromol kg(-1) min(-1). These results suggest that exogenous NO can diminish the ruminal contractions, while endogenous NO is not involved in the regulatory mechanism of basal tone and regular phasic contractions of the rumen in healthy sheep.

Animals↗
PubMed2001

Assessment of colorectal lesions using magnifying colonoscopy and mucosal dye spraying: can significant lesions be distinguished?

BACKGROUND AND STUDY AIMS: Assessing the nature of lesions at the time of colonoscopy is important, and magnifying colonoscopy allows examination of mucosal crypt patterns. In this study, we assessed mucosal crypt patterns to see whether we could predict the histological findings. PATIENTS AND METHODS: This retrospective study of total colonoscopy using magnifying colonoscopy involved 4445 patients between December 1993 and July 1998 at the National Cancer Center Hospital East. The mucosal crypt patterns of 3438 lesions were observed under magnifying colonoscopy with 0.2% indigo carmine solution, and classified according to a modified Kudo classification (type I to V). After endoscopic or surgical resection (3291 cases and 147 cases, respectively), histopathological examination was performed. RESULTS: The diagnostic accuracy of magnifying endoscopy for non-neoplastic lesions was 75% (117/157), for adenomatous polyps it was 94% (3006/3186), and for invasive carcinomas it was 85 % (81/95). CONCLUSIONS: The combination of magnifying colonoscopy and dye spraying is helpful in determining the nature of colonic lesions as non-neoplastic, adenomas, or invasive carcinomas. Therefore it may be possible to determine, at the time of colonoscopy, which lesions require no treatment, which can be removed endoscopically, and which should be removed by surgery.

Adenocarcinoma↗
PubMed2001

Sagittal splitting laminoplasty for spinal canal enlargement for ossification of the spinal ligaments (OPLL and OLF).

Patients have been followed up radiologically after sagittal splitting laminoplasty (SSL) for ossification of the posterior longitudinal ligament (OPLL) and ligamentum flavum. The enlarged spinal canal was maintained satisfactorily in all the cases, and the posterior spinal elements were also almost completely restored. In most cases, the range of the vertebral motion was good with more than 50% of the preoperative status. Postoperative instability of the vertebral column was not identified in any case. Mild cervical kyphosis was noted in 6% of cervical OPLL patients. There were no patients with neurological deterioration. Using SSL, reconstruction and restoration of the posterior spinal elements and retention of the enlarged spinal canal were accomplished safely and adequately.

Female↗
PubMed2001

A new endoscopic tattooing technique for identifying the location of colonic lesions during laparoscopic surgery: a comparison with the conventional technique.

BACKGROUND AND STUDY AIMS: Knowledge of the exact location of colorectal lesions is necessary but difficult to establish during surgery. Thus, endoscopic tattooing has been used as an important preoperative marker for identification. Using the conventional technique, we injected tattooing agents directly into the colonic wall. However, to make sure that the tattooing agents were adequately injected into the submucosal layer, and to prevent spillage into the peritoneal cavity, we modified the conventional method and developed a new tattooing technique: using India ink with prior and subsequent injection of saline into the submucosa. The aim of this study was to retrospectively assess the clinical utility and potential complications of the above two techniques of endoscopic tattooing using India ink. PATIENTS AND METHODS: A total of 153 patients underwent laparoscopically assisted colectomy at the National Cancer Center Hospital East, Kashiwa, Chiba, Japan, between June 1994 and December 1999, and 91 patients underwent preoperative endoscopic tattooing by either the conventional or the new technique. The conventional and new techniques were used from June 1994 to December 1997 (n = 36) and from January 1998 to December 1999 (n = 55), respectively. Informed consent was obtained from all the patients. RESULTS: Using the conventional technique, the exact location of the lesion was identified in 31 of 36 cases (86.1 %) during surgery. The complications of this procedure were silent local peritonitis in two patients and reactive lymph node swelling in one patient (3/36, 8.3 %). Using the new technique, in 54 of 55 cases lesions (98 %) were easily identified (p = 0.034),and in only one there was a small leakage of India ink into the peritoneal cavity (1/55; 1.8 %), no other serious complications were observed. CONCLUSIONS: The results demonstrate that our new technique for endoscopic tattooing is probably better than the conventional technique for clinical use, in terms of diagnostic accuracy and safety, but this would have to be proven in a randomized comparison.

Carbon↗
PubMed2001

A 0.8-mm depressed adenoma of the colon with high-grade dysplasia.

Flat and depressed cancers of the colon have now been recognized in several centers throughout the world. We report here a case of a 0.8-mm depressed adenoma with high-grade dysplasia in a 70-year-old man. We believe this to be the smallest adenoma ever reported, and unusually (for a small lesion) it was positive for the K-ras mutation.

Adenoma↗
PubMed2001

Left ventricular diastolic dysfunction in patients with bronchial asthma with long-term oral beta2-adrenoceptor agonists.

BACKGROUND: Long-term administration of oral beta(2)-adrenergic receptor agonists (beta(2)-AG) in patients with bronchial asthma (BA) causes disastrous events such as sudden death and heart attack. However, long-term effects of beta(2)-AG on cardiac function have not been previously quantified. METHODS: Seventy-four patients with BA with regular long-term use of oral beta(2)-AG (group A) and 69 patients with BA without beta(2)- AG (group B) were examined in medical records of outpatient clinics from 1985 to 1999. In the prospective study, echocardiography was performed in 48 consecutive patients from January to April 1999. There were 26 patients with regular oral use of beta(2)-AG (group a) and 22 patients without beta(2)-AG (group b). Twenty-one age-matched normal volunteers without heart or pulmonary diseases were used as control subjects (group c). Oral beta(2)-AG was withdrawn from remedies in 11 patients of group a, and echocardiographic studies were repeated 2 weeks after its cessation. RESULTS: Events related to heart failure were more frequently seen in group A than in group B (14% vs 1%, P <.01). The echocardiographic study showed that indexes of left ventricular diastolic but not systolic function were significantly deteriorated in group a, along with a markedly reduced level of plasma norepinephrine concentration (P <.05 vs groups b and c). When heart rate was adjusted to 90 beats/min during isoproterenol infusion, left ventricular diastolic function remained deteriorated in group a (P <.05 vs groups b and c). In 11 patients of group a, the cessation of beta(2)-AG for 2 weeks resulted in an improvement of left ventricular diastolic function and in an increase of plasma norepinephrine level (P <.01). CONCLUSIONS: Long-term use of oral beta(2)-AG impaired left ventricular diastolic function in patients with BA, and the cessation of beta(2)-AG reversed diastolic pump performance to the normal level.

Administration, Oral↗