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R Tomita

Publications and source records attributed to R Tomita.

At least 19 recordsLinked to original sources
PubMed2004

Semiquantative analysis of expression of mucosal addressin cell adhesion molecule-1 during small bowel graft rejection in rats.

AIM: Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) mediates the homing of lymphocytes to gut-associated lymphoid tissues (GALT). We performed a semiquantative analysis of MAdCAM-1 expression during small bowel graft rejection. METHODS: Orthotopic small bowel transplantations (SBT) were performed from BN rats to LEW rats. Isografted animals served as controls. Animals were sacrificed on days 3, 4, 5, 6, and 7 after SBT. Cryostat sections were prepared from grafts, including Peyer's patches (PPs). Indirect immunoperoxidase staining was performed using mAbs against MAdCAM-1. The degree of vascular endothelial staining on high endothelial venules (HEV) in the PPs was graded from 1 (low levels) to 5 (high levels), and in the vessels of the lamina propria from 1 (faint), 2 (low at the base of villi), 3 (low to the middle of villi), 4 (high to the middle of villi), to 5 (high to villus tip). RESULTS: MAdCAM-1 expression on HEVs in PPs was down-regulated during rejection. In contrast its expression on endothelial cells of vessels in the lamina propria was up-regulated during rejection. CONCLUSION: Alteration in MAdCAM-1 expression may be associated with the development of SB graft rejection. The vessels at the base of villi, which are associated with lymphocyte recruitment, may become sites of intense immune reactivity during the early phase of small bowel allograft rejection.

Animals↗
PubMed2004

Physiological studies on vasoactive intestinal peptide in rat small bowel isografts.

BACKGROUND: Vasoactive intestinal peptide (VIP) is released by stimulation of nonadrenergic noncholinergic (NANC) inhibitory nerves. In order to evaluate the function of VIP in jejunal isografts, we examined the enteric nerve responses in isografted rat jejunum compared with normal jejunum. METHODS: Orthotopic entire small bowel transplantation (SBT) with portocaval drainage was performed from Lewis rats to Lewis rats. Grafted tissue specimens were obtained 130 days after SBT (n = 8). As controls, normal segments of the jejunum were obtained from nontransplanted Lewis rats (n = 20). A mechanograph was used to evaluate in vitro jejunal responses to electrical field stimulation (EFS) of the adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers and VIP. RESULTS: The isografted jejunum was more strongly innervated by excitatory nerves, especially NANC excitatory nerves, than the normal jejunum (P <.05). VIP mediated relaxation reactions of NANC inhibitory nerves in the normal but to a lesser extent in the isografted jejunum (P <.05). CONCLUSIONS: The increased NANC excitatory nerves and the decreased effects of VIP in mediating NANC inhibitory nerves may largely relate to the peristaltic abnormalities seen in the isografted LEW rat jejunum.

Animals↗
PubMed2004

Apoptosis of crypt cells and lymphocytes in gut-associated lymphoid tissues during small intestinal graft rejection in rats.

INTRODUCTION: We investigated the extent of apoptosis in crypt cells and Peyer's patches (PPs) during small bowel allograft rejection in rats to examine whether the Fas/FasL pathway participates in apoptosis within grafts during rejection. MATERIALS AND METHODS: Orthotopic small bowel transplantation with portocaval drainage was performed from Brown Norway to Lewis (LEW) rats. Isografted (LEW --> LEW) and nontransplanted animals served as the controls. Animals were sacrificed on days 3, 5, on 7 after SBT (each n = 5). An in situ end-labeling (ISEL) technique was used to detect apoptotic cells. Indirect immunoperoxidase staining was also performed using monoclonal antibodies against rat Fas or Fas-L. RESULTS: The number of ISEL-positive enterocytes in the allografts increased significantly on days 3, 5, and 7. Similarly, in the PPs of the allografts, the number of ISEL-positive mononuclear cells increased significantly on days 3, 5, and 7. On day 7 the number of Fas- and FasL-positive enterocytes were increased significantly in the allografts compared with the nontransplanted controls. Similarly, in the PPs, Fas- and FasL-positive mononuclear cells also increased significantly on day 7 in the allograft. CONCLUSION: Although an increase, number of apoptotic enterocytes and lymphocytes were observed in the early phase, activation of Fas/FasL system occurred during the late phase of small bowel graft rejection. These findings suggest that both rejection-associated and sepsis-induced forms of apoptosis may be associated with small bowel graft rejection.

Animals↗
PubMed2003

Expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) during small-bowel graft rejection in rats.

BACKGROUND: Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is a critical endothelial adhesion molecule for lymphocyte trafficking to gut-associated lymphoid tissues (GALT) under physiological conditions. It is expressed on special postcapillary venules, that is the high endothelial venules (HEV) in GALT. In this study, we investigated changes in MAdCAM-1 expression during small-bowel graft rejection. METHODS: Orthotopic small-bowel transplantation (SBT) with portocaval drainage was performed from brown Norway (BN) rats to Lewis (LEW) rats. Isografted (LEW --> LEW) and untransplanted animals served as controls. Animals were killed on days 3, 4, 5, 6 and 7 after SBT. Cryostat sections (6 microm thick) were prepared from normal small-bowel tissues and small-bowel grafts, including Peyer patches (PPs). Indirect immunoperoxidase staining was performed using monoclonal antibodies (mAbs) against rat MAdCAM-1 (OST12). RESULTS: In the PPs of controls, MAdCAM-1 antibodies specifically stained the endothelial cells of HEV, which were predominantly located in the interfollicular areas. In the allografts on day 4 after SBT, the MAdCAM-1 expression was weaker on the HEV in the PPs than in the controls. In the lamina propria of controls, a faint expression of MAdCAM-1 on vessels was observed. On day 4 after allogeneic SBT, the MAdCAM-1 was more strongly expressed on the endothelial cells of the vessels at the base of the villi. As rejection developed, the MAdCAM-1 expression on the vessels progressed toward the villus tip. CONCLUSIONS: The change of MAdCAM-1 expression may be involved in the development of small-bowel graft rejection. The vessels at the base of villi, which is associated with lymphocyte recruitment, may become a site of intense immune reactivity in the early phase of small-bowel allograft rejection.

Animals↗
PubMed2002

Analysis of pancreaticobiliary ductal union based on intraoperative cholangiography in patients undergoing laparoscopic cholecystectomy.

BACKGROUND: In order to diagnose pancreaticobiliary maljunction (PBM), it is necessary to perform direct fluoroscopic examinations of the biliary tract system. For patients with benign biliary diseases, these examinations are performed only in selected cases, because they are generally invasive. We investigated whether intraoperative cholangiography was practicable in evaluating the presence of PBM in patients with benign biliary diseases who underwent laparoscopic cholecystectomy (LC). METHOD: Between March 1998 and February 2001, intraoperative cholangiography (IOCG), which is one of the direct fluoroscopic examinations, was attempted in all 100 patients who underwent LC. RESULTS: IOCG was completed successfully in 98 patients (98.0%). No complications associated with IOCG occurred. In 13 (13.3%) of 98 patients, IOCG showed reflux of contrast medium into the pancreatic duct through a common channel. 'A long common channel' was observed in 8 cases (8.2%), suggesting the presence of PBM. CONCLUSION: These results suggest that IOCG in LC may be a practicable method for detecting the presence of PBM.

Adult↗
PubMed2001

Operative technique on nearly total gastrectomy reconstructed by interposition of a jejunal J pouch with preservation of vagal nerve, lower esophageal sphincter, and pyloric sphincter for early gastric cancer.

Nearly total gastrectomy preserving the vagal nerve, the lower esophageal sphincter (LES), and the pyloric sphincter was developed as a function-preserving surgical technique to improve postgastrectomy disorders. In this paper, application criteria and technique are outlined, and postoperative quality of life was clinically investigated. Ten subjects who underwent this surgical operation (group A: 7 male and 3 female subjects at age 48 to 68 years with a mean age of 58.3 years) were interviewed to inquire about reflux esophagitis, dumping syndrome, and microgastria. Group A was compared with 20 cases of conventional total gastrectomy with D2 lymphadenectomy, excision of the lower esophageal sphincter (LES), total vagotomy, and single jejunal interposition (group B: 16 male and 4 female subjects at age 48 to 72 years with a mean age of 63.9 years). Included were cases with early cancer (M or SM1 of N0) localizing at the middle third and lower stomach, which was not applicable to endoscopic excision of gastric mucosa or partial gastric excision in M cancer, 2 cm or farther from the margin of the cancer to the esophagogastric mucosa cephalad junction and 3.5 cm or farther from the margin of the cancer to the pyloric caudad sphincter; in SM1 cancer, 4 cm or farther from the oral-side margin of the cancer to esophagogastric mucosa junction and 5.5 cm or farther from the anal-side margin of the cancer to the pyloric sphincter. In excision with lymph nodes, hepatic and celiac branches bifurcating from anterior and posterior trunks of the vagal nerve were preserved. To preserve LES, the esophagus was severed at the His angle at right angle to the longitudinal axis of the esophagus. The antrum was severed at 1.5 cm from the pyloric sphincter, preserving the arteria supraduodenalis. An alternative gaster was created as a 15-cm jejunal pouch with a 5-cm jejunal conduit for orthodromic peristaltic movement, using an automatic suture instrument to complete side-to-side anastomosis of folded jejunum with 1- to 1.5-cm long upper end of the pouch not anastomosed. The abdominal esophagus was mechanically anastomosed with a jejunal J pouch, and anastomosis of the pyloric antrum with a jejunal conduit was manually completed by stratum anastomosis. In group A, food ingestion per time could be taken the same as that of a healthy person, with no reflux esophagitis and dumping syndrome being noticed. Reflux esophagitis developed more significantly in group B than in group A (p < 0.05). In food ingestion per time, group B was significantly delayed compared with group A (p < 0.05). The present results suggested that the surgical technique proposed is a function-preserving gastric surgery appropriate to prevent postgastrectomy disorder of subjects.

Aged↗
PubMed2001

The role of nitric oxide (NO) in the human internal anal sphincter.

PURPOSE: Nitric oxide (NO) has recently been shown to be a neurotransmitter in nonadrenergic noncholinergic (NANC) inhibitory nerves in the human gut. To clarify the physiological significance of NO in the human internal anal sphincter (IAS), we investigated enteric nervous responses in normal IAS muscle strips above the dentate line, obtained from patients with rectal cancer. METHODS: Normal IAS muscle strips above the dentate line, obtained from ten patients who underwent rectal amputation for low rectal cancers were used. The subjects consisted of eight men and two women, aged from 46-72 years (mean age, 54.2 years). A mechanographic technique was used to evaluate in-vitro IAS muscle responses to electrical field stimulation (EFS) of adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers, N(G)-nitro-L-arginine (L-NNA) and L-arginine. RESULTS: Excitatory nerves were mainly involved in the regulation of enteric nerve responses to EFS in the baseline condition of the study, and NANC inhibitory nerves acted on the normal IAS. L-NNA concentration-dependently inhibited the relaxation in response to EFS in the human IAS, and this inhibitory effect in the IAS was reversed by L-arginine. CONCLUSIONS: These findings suggest that NANC inhibitory nerves play important roles in regulating relaxation of the human IAS, and that NO plays an important role as a neurotransmitter in NANC inhibitory nerves of the human IAS.

Aged↗
PubMed2001

Laparoscopic extended cholecystectomy.

BACKGROUND: Inadvertent dissemination of latent gallbladder (GB) cancer has become a crucial issue with the widespread use of laparoscopic cholecystectomy as a standard operation for benign gallbladder diseases. METHODS: Laparoscopic extended cholecystectomy is a new technique we have developed for the resection of GB tumors with suspicion of malignancy. The procedure is safe and minimally invasive and prevents tumor dissemination. The GB is resected laparoscopically along with a 1-cm margin of the liver using LaparoSonic Coagulating Shears without any ligation or clipping. RESULTS: We applied this technique to a patient with a GB tumor in the fundus. The tumor was not exposed on the cut surface, and there were no postoperative complications. CONCLUSION: Laparoscopic extended cholecystectomy for GB tumors with suspicion of malignancy is a minimally invasive technique that may decrease the risk of tumor dissemination.

Cholecystectomy, Laparoscopic↗
PubMed2000

Segregation of a pure form of spastic paraplegia and NOR insertion into Xq11.2.

A 3-year-old boy, his 7-year-old brother, and a maternal uncle had a pure form of spastic paraplegia and a variant X chromosome with a faintly stained gap at Xq11.2. The mother of the propositus also had the variant X chromosome but was clinically unaffected. Three other unaffected females in the family did not have the variant X chromosome. The gaps in the variant X chromosome from the affected members and the mother were Ag-NOR staining positive, C-banding negative, rDNA FISH analysis positive, and alpha-satellite FISH analysis negative. The gap, therefore, represented an insertion of the nucleolus organizer region (NOR) derived from the short arm of an acrocentric chromosome. The variant X chromosome of the mother was randomly inactivated, as evidenced by BrdU replication analysis of her Epstein-Barr virus-transformed lymphoblastoid cells. Because mutations of the proteolipid protein gene at Xq21 have been responsible for a pure form of spastic paraplegia, this was also investigated but found to be negative in all affected relatives. Summing up these findings, it is proposed that the NOR insertion in the affected members of the family disrupted a hitherto unknown gene for a pure form of spastic paraplegia, situated at Xq11.2, and caused the disorder.

Adult↗
PubMed2000

Relation between gastroduodenal interdigestive migrating motor complex and postoperative gastrointestinal symptoms before and after cisapride therapy following distal gastrectomy for early gastric cancer.

A total of 30 patients (18 men, 12 women; 43-79 years, mean 58.9 years) 1.0 to 1.5 years (mean 1.25 years) after distal gastrectomy for early gastric cancer (Billorth I, D2 lymph node dissection, curability A) were divided into two groups based on the occurrence of interdigestive migrating motor complex (IMMC) phase III (pIII) from the duodenum and their postoperative gastrointestinal symptoms. They were compared before and after cisapride therapy (at an oral dose of 7.5 mg/day for 3 months). Results were as follows. Before cisapride therapy: (1) Patients in the IMMC-pIII-positive group (n = 20) had more appetite and ate more food with less decrease in body weight than those in the IMMC-pIII-negative group (n = 10); (2) patients in the IMMC-pIII-positive group clearly had fewer symptoms, such as early dumping (systemic) symptoms, symptoms of reflux esophagitis (e.g., heartburn, feeling of regurgitation, difficult swallowing), nausea, abdominal pain, diarrhea, abdominal distension, and borborygmus, than the IMMC-pIII-negative group. After cisapride therapy: eight patients (80%) in the IMMC-pIII-negative group became IMMC-pIII-positive, and their appetite and food consumption were obviously improved; body weight increased in six patients (60%), with alleviation of other abdominal symptoms and disappearance of the early dumping syndrome. These results showed a more satisfactory condition in regard to gastrointestinal symptoms in the IMMC-pIII-positive group than in the IMMC-pIII-negative group. It is concluded that cisapride therapy results in the occurrence of IMMC-pIII and subsequently alleviates various abdominal symptoms, contributing to the improved postoperative gastrointestinal condition of patients after gastrectomy.

Adult↗
PubMed2000

Antisense oligodeoxynucleotides to human inducible nitric oxide synthase selectively inhibit induced nitric oxide production by human vascular endothelial cells: an experimental study.

OBJECTIVE: To find out whether the antisense oligodeoxynucleotide designed against the complementary DNA to human inducible NO synthase (iNOS) would block the translation from iNOS mRNA to NO in human vascular endothelial cells. DESIGN: Prospective controlled study. SETTING: Research laboratory, Japan. MATERIAL: Cultured human vascular endothelial cells. INTERVENTIONS: Human vascular endothelial cells were cultured for 24 hours, and divided into two groups, one of which was exposed to antisense oligodeoxynucleotides and the other to sense oligodeoxynucleotides at 100, 200, 400 and 800 micromol/L, respectively, for 18 hours. They were then exposed to interferon-gamma (1000 units/ml) and recombinant human tumour necrosis factor alpha (500 units/ml) to stimulate NO production. Each experiment was repeated ten times. RESULTS: Clear bands expressing cDNA of iNOS mRNA were identified in agarose gels in all cultured cells in both groups. The mean nitrite concentration in the supernatants of cultured cells in the group with the addition of antisense oligodeoxynucleotides was significantly lower than that in the group with sense oligonucleotides added at 200, 400, and 800 micromol/L. CONCLUSION: These findings indicate that the antisense oligodeoxynucleotides inhibited the NO production dependently, by preventing only their translation but not the processing, before their transcription from DNA into iNOS mRNA.

Cells, Cultured↗
PubMed1999

Laparoscopic treatment for common bile duct stones by transcystic papilla balloon dilatation technique.

The laparoscopic transcystic common bile duct (CBD) approach is becoming increasingly more refined as an ideal technique to deal with gallbladder stones (GBS) and common bile duct stones (CBDS) during a single operation. Our method, transcystic CBD exploration and papilla balloon dilatation (PBD), is an easier, safer, and less invasive technique than the transcystic approaches that have previously been reported. With our method, a sheath is introduced through the cystic duct into the CBD in order to allow catheter exchange, and the CBDS is flushed out through the papilla into the duodenum after PBD. We applied our new technique, without complication, to a patient with GBS and CBDS. Our technique is one of the safest, easiest, and least invasive methods for the treatment of patients with GBS and CBDS.

Ampulla of Vater↗