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.

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.

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.

A novel operative technique on proximal gastrectomy reconstructed by interposition of a jejunal J pouch with preservation of the vagal nerve and lower esophageal sphincter.

BACKGROUND/AIMS: This article describes the surgical techniques and postoperative status for proximal gastrectomy reconstructed by interposition of a jejunal J pouch with preservation of the vagal nerve and lower esophageal sphincter. METHODOLOGY: We have performed a new technique for reducing postgastrectomy sequelae such as reflux esophagitis, early dumping syndrome, and microgastria in early gastric cancer located in the proximal third of the stomach. The technique consists of proximal gastrectomy with preservation of the hepatic, pyloric, celiac branch of the vagal nerve, and abdominal esophagus (lower esophageal sphincter), and reconstruction by interposition of a jejunal J pouch. To reserve pyloric function, pyloroplasty can be omitted by preservation of the pyloric branch from the vagal nerve. To restore loss of reservoir function, the reconstruction is performed with an interposed jejunal J pouch. Sacrifice of the mesenteric arcades is kept to a minimum to preserve the autonomic nerve and blood flow in the mesentery. RESULTS: All of the patients who underwent this operation were able to eat an adequate amount of food at 6 months after surgery and they were satisfied with their postoperative status. And that, we have not experienced postgastrectomy disorders such the dumping syndrome and reflux esophagitis. CONCLUSIONS: Therefore, this method is useful for preventing the postoperative disorders in patients with early gastric cancer located in the proximal third of the stomach.

Yeast Saccharomyces cerevisiae has two cis-prenyltransferases with different properties and localizations. Implication for their distinct physiological roles in dolichol synthesis.

BACKGROUND: Dolichol is a family of long-chain polyprenols, which is utilized as a sugar carrier in protein glycosylation in the endoplasmic reticulum (ER). We have identified a key enzyme of the dolichol synthesis, cis-prenyltransferase, as Rer2p from Saccharomyces cerevisiae. We have also isolated a multicopy suppressor of an rer2 mutant and named it SRT1. It encodes a protein similar to Rer2p but its function has not been established. RESULTS: The cis-prenyltransferase activity of Srt1p has been proved biochemically in the lysate of yeast cells lacking Rer2p. The polyprenol product of Srt1p is longer in chain length than that of Rer2p and is not sufficiently converted to dolichol and dolichyl phosphate, unlike that of Rer2p. The subcellular localization of these two isozymes has been examined by immunofluorescence microscopy and by the use of GFP fusion proteins. Whereas GFP-Rer2p is localized to the continuous ER and some dots associated with the ER, GFP-Srt1p shows only punctate localization patterns. Immunofluorescence double staining with Erg6p, a marker of lipid particles in yeast, indicates that Srt1p is mainly localized to lipid particles (lipid bodies). RER2 is mainly expressed in the early logarithmic phase, while the expression of SRT1 is induced in the stationary phase. CONCLUSIONS: We have shown that yeast has two active cis-prenyltransferases with different properties. This result implies that the two isozymes have different physiological roles during the life cycle of the yeast.

Prognostic studies on gastric cancer with concomitant liver metastases.

BACKGROUND/AIMS: The aim of this study was to clarify prognostic factors after surgical treatments in gastric cancer patients having synchronous liver metastases. METHODOLOGY: Clinicopathological features and prognosis were retrospectively reviewed in 43 surgical patients with gastric cancer with concomitant liver metastases from 1984 to 1998. RESULTS: More than half of the patients (51.2%) had numerous liver metastases (H3). Rates of peritoneal metastases (P1, P2, P3: 34.9%), tumor serosal invasion (T3 or T4: 73.8%) and widespread lymph node metastases (N3, N4: 69.8%) were also high. Although the gastric resection was performed in 29 patients (67.5%), concomitant hepatectomy resection was performed in only 3 patients (7.0%). Univariate analysis revealed that the grade of liver metastases (H1, H2, H3) was only a statistically significant prognostic factor (P = 0.008). Concerning surgical treatments, the resection group had tendency to better survival than the nonresection group (P = 0.074). Eight cases survived more than 1 year. Seven of the 8 cases (87.5%) were patients with gastrectomy. All of the 5 two-year survivors were patients with gastrectomy. CONCLUSIONS: In patients with gastric cancer with concomitant liver metastases, the grade of liver metastases indicate prognosis. In addition, there is possibility of palliative gastrectomy increasing the survival rare to more than one year.

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.

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.

Relationship between gastroduodenal interdigestive migrating motor complex and quality of life in patients with distal subtotal gastrectomy for early gastric cancer.

A total of 40 patients (28 males, 12 females; mean age, 56.6 years; range, 41-72 years), 1-1.5 years (mean, 1.4 years) after subtotal gastrectomy for early gastric cancer (Billroth I, D2 lymph node dissection, curability A) were divided into 2 groups according to the occurrence of interdigestive migrating motor complex (IMMC), phase III from the duodenum, and their postoperative quality of life was compared. Results were as follows: (i) patients in the IMMC, phase III positive group (28 patients) had evidently more appetite and ate more food, with less decrease in body weight compared with the IMMC, phase III negative group (12 patients); and (ii) patients in the IMMC, phase III positive group had clearly less symptoms, such as early dumping symptoms (systemic symptoms), symptoms of reflux esophagitis (e.g. heartburn, feeling of regurgitation, difficult swallowing), nausea, abdominal pain, diarrhea, abdominal distention, and borborygmus, compared with the negative group. These results showed more satisfactory quality of life in the IMMC, phase III positive group compared with the negative group.

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.

Role of nitric oxide in the left-sided colon of patients with diverticular disease.

BACKGROUND/AIMS: Non-adrenergic non-cholinergic inhibitory nerves are the most important nerves in the enteric nervous system of the human gut. Recently, it has been established that nitric oxide is released by stimulation of non-adrenergic non-cholinergic inhibitory nerves. Therefore, in order to evaluate the function of nitric oxide in the left-sided colon of patients with diverticular disease, we examined the enteric nerve responses in colonic tissues from patients with this disease, and also used the left-sided normal colon as a control. METHODOLOGY: Colonic tissue specimens (the diverticular bearing segments) were obtained from 9 patients with diverticular disease of the left-sided colon, and normal segments of the left-sided colon were obtained from 16 patients with ascending colon cancer. A mechanograph was used to evaluate in vitro colonic responses to electrical field stimulation of adrenergic and cholinergic nerve before and after treatments with various autonomic nerve blockers, NG-nitro-L-arginine, and L-arginine. RESULTS: 1) The diverticular colon was more strongly innervated by cholinergic nerves than the normal colon (P < 0.01); 2) Non-adrenergic non-cholinergic inhibitory nerves were found to act on the normal colon and to a lesser extent in the diverticular colon (P < 0.05). 3) Nitric oxide mediates the relaxation reaction of non-adrenergic non-cholinergic inhibitory nerves in the normal colon and to a lesser extent in the diverticular colon. CONCLUSIONS: These findings suggest that the intrinsic intestinal innervation contains excitatory and inhibitory nerves and that the former, especially cholinergic nerves, are dominant in the left-sided colon with diverticula. In addition, diminution of action of non-adrenergic non-cholinergic inhibitory nerves by substances such as nitric oxide may be largely related to the high intraluminal pressure by colonic segmentation observed in the left-sided colon with diverticula.

[Proposed mechanism of action of metalloendopeptidase-F in the treatment of patients with chronic hepatitis B or C infection].

Chronic hepatitis B and C virus infections have been characterized by the pathophysiological features with a high incidence of progression to cirrhosis and development of hepatocellular carcinoma. The viral persistence produced by escape mutations from virus-specific cytotoxic T lymphocytes (CTL) response may lead to upregulation of delayed-type hypersensitivity immune response, which causes hepatic tissue damage through non specific macrophage activation and CTL response and promotes pathogenesis of hepatic fibrosis. In a preliminary clinical study, a novel metalloendopeptidase-F (MEP-F) has been shown to be effective in the treatment of patients with either chronic hepatitis B or C infection. Oral administration of MEP-F resulted in a significant reduction of the serum levels of HBs antigen and HCV RNA and improvement in the liver function abnormalities. However, the mechanism of action of MEP-F is not yet well understood. There are accumulating evidences showing an important role of alpha 2-macroglobulin-proteinase complexes in regulatory mechanisms of immune response and repairing within impaired and inflammatory tissues. In this article, reviewing the pharmacological and biological properties of alpha 2-macroglobulin-proteinase complexes, the mechanism of anti-viral effect of MEP-F is examined based on the clinical findings. It is indicated that alpha 2-macroglobulin-MEP-F complexes may induce macrophage/Kuppfer cell activation and proliferation through binding their receptors on the cells and activating signaling cascades, which enhance both anti-viral specific and nonspecific immune responses. alpha 2-Macroglobulin-MEP-F complexes may also augment cellular immunity and hepatic regeneration by neutralizing the immunosuppressive and fibrogenic activities of transforming growth factor-beta.

Peptidergic nerves in the colon of patients with ulcerative colitis.

BACKGROUND/AIMS: The cause of impaired motility, such as diarrhea and toxic megacolon, in patients with ulcerative colitis is unknown. Neuropeptides have recently been shown to be a neurotransmitter in the non-adrenergic non-cholinergic inhibitory and excitatory nerves in the human gut. To clarify the physiological significance of vasoactive intestinal polypeptide, substance P and neurotensin in the colon of patients with ulcerative colitis, we investigated the enteric nerve responses on lesional and normal bowel segments derived from patients with ulcerative colitis and patients who underwent colon resection for colonic cancers. METHODOLOGY: Twenty-four specimens were obtained from the lesional colon of 6 patients with ulcerative colitis (4 male, 2 female; ages 14-51 years, mean: 40.3 years). The patients with ulcerative colitis had chronic disease (4 with moderate disease, 2 with severe disease). Seventy-two specimens were obtained from the normal colon of 10 patients with colonic cancer (8 men and 2 women; ages 40-56 years, mean: 51.2 years). A mechanographic technique was used to evaluate in vitro muscle responses to these peptides of adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers. RESULTS: (1) Peptidergic nerves such as vasoactive intestinal polypeptide, substance P, and neurotensin nerves were found to act on both normal colon and ulcerative colitis colon; (2) the colon with ulcerative colitis was more strongly innervated by vasoactive intestinal polypeptide nerves than the normal colon; (3) Substance P and neurotensin nerves act more weakly in the UC colon that the normal colon. CONCLUSIONS: These findings suggest that peptidergic nerves play an important role in the impaired motility observed in patients with UC.

[A study on development of enzyme immunoassay of human osteopontin: molecular fragility of serum osteopontin].

Osteopontin, a secreted acidic phosphoglycoprotein with calcium binding activity, has been reported to have diverse functions, including cell adhesion, calcium remodeling, cell signaling and cellular transformation. This recalls us to a concept that the osteopontin can be a marker for certain clinicopathological states. However, a method for analysis of osteopontin has not successfully been developed to be utilized. We have isolated osteopontin from human milk, prepared antibodies specific to it, and tried to establish an enzyme immunoassay (EIA) system to determine osteopontin in serum. It was found that serum osteopontin but not milk osteopontin showed paradoxical phenomena in reaction with the antibodies, i.e., no detectable reaction in immunoelectrophoresis and in EIA, but showing positive reaction in Western blot and in inhibition tests. Taking these phenomena and other circumstantial evidence into account, it was concluded that the serum osteopontin had high molecular fragility, fragmenting into small peptides with paucity of epitopes during incubation time. These findings indicate the possible presence of osteopontins with different molecular characteristics among tissues, and that these characteristics of osteopontin will interfere with the development of quantitative assay.

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

BACKGROUND/AIMS: Nitric oxide (NO) has recently been shown to be a neurotransmitter in non-adrenergic non-cholinergic (NANC) inhibitory nerves in the gastrointestinal tract. To clarify the role of NO in the human pyloric sphincter, enteric nerve responses in pyloric tissue specimens obtained from patients with gastric cancer were investigated. METHODOLOGY: Fresh specimens of normal pylorus obtained from 18 patients with gastric cancer were used. The subjects consisted of 12 men and 6 women, aged from 45-74 years (average: 60.1 years). A mechanograph was used to evaluate in vitro pyloric sphincter muscle responses to electrical field stimulation (EFS) of adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers, and N(G)-nitro-L-arginine (L-NNA) and L-arginine. RESULTS: Cholinergic nerves were mainly involved in the regulation of enteric nerve responses to EFS in the basal condition of the study, and NANC inhibitory nerves acted on human pylorus. L-NNA concentration dependently inhibited the relaxation in response to EFS in the human pylorus, and this inhibitory effect in the pylorus was reversed by L-arginine. CONCLUSIONS: These findings suggest that the cholinergic/adrenergic and NANC inhibitory nerves play important roles in regulating contraction and relaxation of the human pylorus, and that NO plays an important role as a neurotransmitter in NANC inhibitory nerves of the human pylorus.