PubMed Health⌕ Search

Biomedical subjects

Yasuhide Morikawa

Publications and source records attributed to Yasuhide Morikawa.

17 recordsLinked to original sources
PubMed2006

Novel application of ProteinChip technology exploring acute rejection markers of rat small bowel transplantation.

BACKGROUND: Because no biomarker that reflects small bowel allograft rejection is available, we applied surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) to develop noninvasive markers required for routine diagnosis. METHODS: Heterotopic small bowel transplantation (SBT) was performed in rats, and they were divided into four experimental groups: sham-operated rats (sham), syngeneic transplants (syngeneic), allogeneic transplants (allogeneic), allogeneic transplants received FK506 (allo+FK). Plasma samples were analyzed with SELDI ProteinChip arrays to detect peaks that predominated in the allogeneic model. Possible biomarkers were identified in combination with SELDI retentate chromatography mass spectrometry (RCMS) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The identified protein was further analyzed by immunohistochemistry. RESULTS: An increase in the level of a 14.8-kDa protein, identified as lysozyme, was observed specifically in the plasma of the allogeneic group; the levels of this protein remained unchanged in the plasma of the other groups. On the other hand, the levels of a 10.1-kDa and a 13.0-kDa protein, identified as migration inhibitory factor-related proteins (MRP), MRP-8 and MRP-14, respectively, began to increase from an early stage of acute rejection. We also observed that lysozyme-positive macrophages had strongly infiltrated the lamina propria during acute rejection. CONCLUSIONS: We identified three plasma proteins-MRP-8, MRP-14, and lysozyme-that increased during small bowel allograft rejection. The identified proteins appeared to be markers for inflammation associated with allograft rejection. This proteomic approach will be useful for the identification of candidate biomarkers.

Amino Acid Sequence↗
PubMed2006

Interstitial cells of Cajal in dysmotility in intestinal ischemia and reperfusion injury in rats.

BACKGROUND: Intestinal ischemia and reperfusion (I/R) injury is an obligatory occurrence in small bowel transplantation. I/R may impair the normal gastrointestinal motility. Interstitial cells of Cajal (ICC) are known as pacemaker cells in the gastrointestinal tract. The aim of this study was to assess the role of ICC in the gastrointestinal motility in a rat model of I/R injury. MATERIALS AND METHODS: Wistar rats were subjected to 30- or 80-min intestinal ischemia by occluding the mesenteric vessels followed by reperfusion. Small intestinal segments were resected at 12 h or 4 days. The spontaneous mechanical activity was evaluated by organ bath technique. Immunopositivity of c-Kit and PGP9.5 at the level of the myenteric plexus was evaluated as markers of ICC and enteric nerves, respectively. RESULTS: In the bowel segment with 80-min ischemia followed by 12-h reperfusion, muscles showed a 25% reduction (P < 0.05) in the frequency of contractions compared to that with 30-min ischemia followed by 12-h reperfusion, whereas amplitude of contractions was not significantly different. This change was associated with a 70% decrease (P < 0.01) of c-Kit immunopositivity. These changes of intestinal motility pattern and distribution of c-Kit-positive cells were both recovered from 80-min ischemia followed by 4 days reperfusion. In contrast, the immunopositivity of PGP9.5 was not affected in any I/R injury group. CONCLUSIONS: Transient functional changes in ICC were induced by prolonged I/R injury but they recovered after 4 days, suggesting a central role of ICC in both disrupting and restoring the normal gastrointestinal motility in I/R injury.

Animals↗
PubMed2006

Cryptogenic fulminant hepatic failure in infancy: report of 2 cases with unique vascular obstructive changes in native livers.

Although the causes of fulminant hepatic failure (FHF) remain cryptogenic in many cases, a few reports have reviewed the pathological findings of native livers to evaluate the etiology. We report 2 cases of infantile cryptogenic FHF with unique vascular obstructive changes in the native livers. Clinically, it was notable that these 2 patients developed FHF very early in life, at 2 months and 5 months of age, respectively. One patient died from chronic rejection associated with hepatic veno-occlusive disease 4 months after transplantation. Histologically, hepatocytes in the native livers were completely destroyed in both patients, and vascular findings revealed obstruction of central veins in 1 patient and obstruction of portal veins in the other patient. Although the pathogenesis of vascular obstructions is not yet understood, this study suggests that an obstructive vascular event may be a contributing etiologic factor of FHF in infancy.

Blood Vessels↗
PubMed2006

Increased serum and hepatic tissue levels of interleukin-18 in patients with fulminant hepatic failure.

BACKGROUND: Fulminant hepatic failure is a serious clinical condition associated with a high mortality rate. Interleukin (IL)-18 is a pro-inflammatory cytokine that is associated with several inflammatory diseases. The purpose of the present paper was therefore to investigate whether IL-18 is elevated in patients with fulminant hepatic failure. METHODS: Serum levels of IL-18 were measured in patients with fulminant hepatic failure before and after liver transplantation. Native liver tissue samples were collected and the tissue levels of IL-18 were determined. Liver tissues were stained immunohistochemically with antihuman IL-18 antibody. The serum levels of IL-1beta, IL-6, IL-8, IL-12, interferon-gamma, and tumor necrosis factor-alpha were also determined in patients with fulminant hepatic failure before and after liver transplantation. RESULTS: Elevated levels of IL-18 in serum and hepatic tissue were observed in patients with fulminant hepatic failure. Native liver tissue samples were immunohistochemically positive for IL-18. Interleukin-18 levels were markedly reduced after liver replacement. No other inflammatory cytokines were substantially elevated in patients with fulminant hepatic failure. CONCLUSION: The serum levels of IL-18 levels are elevated much more than those of other cytokines in patients with fulminant hepatic failure.

Case-Control Studies↗
PubMed2005

Imatinib blocks spontaneous mechanical activities in the adult mouse small intestine: possible inhibition of c-Kit signaling.

Interstitial cells of Cajal (ICCs) are postulated to serve as pacemakers that physiologically generate electrical slow waves in the gastrointestinal tract. Imatinib is a novel and potent inhibitor of c-Kit tyrosine kinase and a new therapeutic agent for gastrointestinal stromal tumors (GIST) which presumably arise from ICCs. The effects of imatinib on the basal rhythmic mechanical activities of small intestinal circular muscles were investigated in ring preparations of the gut. The small intestinal rings of BALB/c mice exhibited spontaneous contractile activity at a rate of 40.8 +/- 4.9 contractions/min. Imatinib (1- 81 micromol/l) dose-dependently abolished spontaneous contractile activity in the 9- to 27-micromol/l concentration range. Contraction was restored by washing imatinib out with a fresh buffer. High K(+)-induced contraction was not affected by imatinib, suggesting that the drug does not have nonspecific inhibitory actions on the smooth muscles. The small intestinal rings of adult W/W(v)mice, which lack a functional c-Kit activity,exhibited only small and irregular spontaneous contractions. These results demonstrate that imatinib affects bowel contractions, and suggest that the c-Kit signaling of ICCs plays an essential role in the spontaneous movements in circular muscles of the mouse small intestine.

Animals↗
PubMed2005

[Childhood rhabdomyosarcoma].

Overall five-year survival of Childhood rhabdomyosarcoma (RMS) is reported to be 70% in the Intergroup Rhabdomyosarcoma Study Group (IRSG), however, the figure in Japan is almost 15% lower than that of IRSG. Treatment regimen of RMS essentially depends on the histology of the tumor, site, preoperative staging and postoperative grouping that leads to the risk classification. VAC is a standard chemotherapeutic regimen for low and intermediate risk group. Clinical trial with CPT-11 or high dose chemotherapy are underway for high risk RMS.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

No incidence of port-site recurrence after endosurgical procedure for pediatric malignancies.

Port-site recurrence (PSR) following laparoscopic procedures has been an unpredictable complication in adult cancer patients; however, no data exist about this phenomenon in the pediatric field. The aim of this study was to determine whether PSR, following endosurgical procedure for malignancies, is a typical complication or a rare event in the pediatric population. Eighty-one questionnaires were mailed to members of The Japanese Society of Pediatric Endosurgeons. They were asked to provide a list of their institutions that had experience with PSR after endosurgical procedures for pediatric malignancies. Among 29 institutions, a total of 129 endosurgical procedures for pediatric malignancies were reported; these included 85 laparoscopic and 44 thoracoscopic procedures, performed on 104 neuroblastomas, 8 hepatoblastomas, 7 nephroblastomas, and 10 other tumors. Of the 104 neuroblastomas, 83 were found by mass screening using high levels of urinary vanillylmandelic acid and homovanillic acid. Sixty-five of the 83 patients had their tumor excised, and 18 had their tumor biopsied by endosurgical procedures. Additionally, 47 of these patients did not require any postoperative chemotherapy. No incidence of PSR was reported in any of the patients that underwent endosurgical procedures. The PSR following endosurgical procedure is a rare phenomenon in the pediatric population. Both, laparoscopic and thoracoscopic procedures, are safe and recommended for treating pediatric malignancies, especially mass-screened neuroblastomas.

Child↗
PubMed2003

Colorectal motility induction by sacral nerve electrostimulation in a canine model: implications for colonic pacing.

PURPOSE: This study investigated the role of the sacral nerves in the mechanism of defecation using adult mongrel dogs. The possibility of designing a colonic pacemaker as a new therapeutic device to treat defecation disturbances, such as fecal incontinence and severe constipation, is also discussed. METHODS: Colorectal motility during spontaneous defecation was monitored with force strain-gauge transducers implanted in the proximal, distal, and sigmoid colon, rectum, and internal anal sphincter. Under general anesthesia, the sacral nerve was stimulated electrically, and the colorectal motility response was examined. RESULTS: During spontaneous defecation, three characteristic motility patterns were observed: 1) giant migrating contractions of the colon were propagated to the rectum or anus; 2) the rectum relaxed before the giant migrating contractions were propagated; and 3) the internal anal sphincter was relaxed during the propagation of the giant migrating contraction. Sacral nerve stimulation elicited the following three unique responses: 1) contractile movements were propagated from the distal colon to the rectum; 2) a relaxation response was noted in the rectum; and 3) the internal anal sphincter exhibited a relaxation response. The duration and propagation velocity of the contractile responses and the duration of relaxation responses elicited by electrical stimulation of the sacral nerve were similar to those that occurred during spontaneous defecation, but their amplitudes were smaller. CONCLUSION: The coordinated processes of the colon and anorectum during defecation were affected by the sacral nerves. This suggests that it is possible to design a colonic pacemaker to control lower colonic and rectal movements.

Animals↗
PubMed2003

A role of cytokines in OK-432 injection therapy for cystic lymphangioma: an approach to the mechanism.

PURPOSE: This study examines cytokine levels of aspirates from cystic lymphangiomas after injection of OK-432 and over the course of several weeks to better understand the process of tumor regression. METHODS: Fluids aspirated from lymphangioma cysts of 3 patients were collected sequentially before and after OK-432 injection. Mononuclear cells (MNCs) were separated and cultured with or without OK-432. Vascular endothelial growth factor (VEGF), soluble VEGF receptor 1 (sVEGFR1), sVEGFR2, transforming growth factor beta-1 (TGF-beta1), interleukin (IL)-6, IL-8, IL-12+p40, tumor necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) levels in the supernatants of the aspirates and the culture supernatants of MNCs were then measured by ELISA. RESULTS: The aspirates exhibited a marked elevation in IL-6, IL-8, VEGF, and TGF-beta1 levels for a few weeks after the OK-432 injection. IL-6, IL-8, IL-12+p40, TNF-alpha, and IFN-gamma levels were elevated in the culture supernatants of the MNC cultured with OK-432 for up to 9 days. All the tumors regressed significantly, with sclerotic change, within 3 months after OK-432 injection. CONCLUSIONS: Cytokine production is maintained for a few weeks after OK-432 injection. Fibrotic changes may be another main mechanism in tumor regression in addition to cytotoxic effects on lymphangioma cells. A close relationship between cytokines from intracystic cells and lymphangioma cells is suggested.

Child, Preschool↗
PubMed2002

Intraportal infusion therapy as a novel approach to adult ABO-incompatible liver transplantation.

BACKGROUND: ABO-incompatible liver transplantation is associated with an extremely complicated postoperative course, especially when the recipients are adults. METHODS: Two adult patients underwent living-donor liver transplantation from ABO-incompatible donors. The antirejection therapy included multiple perioperative plasmapheresis, splenectomy, systemic triple immunosuppressive regimen with tacrolimus, methylprednisolone, and cyclophophamide, or azathioprine. In addition to these conventional approaches, we performed intraportal infusion therapy after transplantation with methylprednisolone, prostaglandin E1, and gabexate mesilate. RESULTS: With our protocol, antidonor blood group antibody titers in both cases remained low without any evidence of rejection or vascular complications throughout the postoperative course. Biliary complications were transient and resolved completely. The patients have now survived 30 and 12 months posttransplantation and have regained normal life activity with good liver function. CONCLUSIONS: Our experience has shown the feasibility of controlling rejection and other complications in adult ABO-incompatible liver transplantation under intraportal infusion therapy.

ABO Blood-Group System↗
PubMed2002

Biliary complications in adult living donor liver transplantation with duct-to-duct hepaticocholedochostomy or Roux-en-Y hepaticojejunostomy biliary reconstruction.

BACKGROUND: The aim of this study was to compare the incidence of biliary complications after adult living donor liver transplantation (ALDLT) with Roux-en-Y hepaticojejunostomy (R-Y HJ) or duct-to-duct hepaticocholedochostomy (D-D HC). METHODS: Biliary complications were reviewed in 20 consecutive ALDLT recipients surviving more than 1 month, including 10 patients who underwent R-Y HJ and 10 patients who underwent D-D HC reconstructions. RESULTS: Ten biliary complications were seen in 8 patients (40%) from the study group. Specifically, 1 case of biliary leakage and 1 case of biliary hemorrhage were observed in the R-Y HJ group (20%), and 2 biliary leakages, 4 biliary strictures, and 2 C-tube related biliary leakages were seen in 6 patients from the D-D HC group (60%). Three of the 5 patients (60%) who underwent right lobe graft ALDLTs experienced biliary stricture. All cases of biliary leakage and biliary hemorrhage were stopped spontaneously by continuous drainage. Three patients in the D-D HC group with anastomotic strictures were successfully treated with percutaneous interventions. Only 1 patient with anastomotic stricture in the D-D HC group with left lobe graft required intrahepatic R-Y HJ reanastomosis. Two cases of C-tube related biliary leakages were treated with endoscopic management. CONCLUSIONS: Biliary complications such as anastomotic strictures were common in the D-D HC group rather than in the R-Y HJ group. D-D HC reconstruction should be applied cautiously, especially in the right lobe graft ALDLT cases.

Adult↗
PubMed2002

A congenital anterior diaphragmatic hernia with massive pericardial effusion requiring neither emergency pericardiocentesis nor operation. A case report and review of the literature.

UNLABELLED: All previously reported cases of anterior, diaphragmatic hernia with massive pericardial effusion were treated by pericardiocentesis and radical surgery during the early neonatal period. However, we initially followed the course of our patient in the neonatal period. Subsequently, elective surgery was performed at 70 days of age. Including our case, cardiac tamponade has not been observed in any previously reported cases of congenital anterior diaphragmatic hernia with massive pericardial effusion. CONCLUSION: Emergency pericardiocentesis and surgery are not always required immediately after birth, even when the presence of this condition is suspected by prenatal diagnosis. Our observation may be beneficial to preterm low birth weight infants with this condition.

Adult↗
PubMed2002

[Endoscopic surgery in children: current status and problems].

Endoscopic surgery has been established in various surgical conditions in children and infants for the past 10 years after pioneering work by experts specializing in pediatric endosurgery. These include pull-through for Hirschsprung's disease and anorectal malformations, pyloromyotomy, hernia repair, and endoscopic surgery for malignancies, malrotation, intussusception, etc. Laparoscopic pull-through is now accepted as a standard modality for the treatment of Hirschsprung's disease. Advanced endoscopic procedures such as esophageal atresia repair or fetal tracheal occlusion have also been performed. An efficient system for training is needed to compensate for the small number of patients and varieties of specific illness in children.

Child↗
PubMed2002

[Intensive therapy for fulminant hepatic failure: importance of co-operation between physicians of internal medicine and transplantation surgery].

We followed up the patients with fulminant hepatic failure who admitted in our hospital and investigated clinical problems raised in the patients who underwent living-related liver transplantation (LRLT). Among 15 patients with fulminant hepatic failure 6 were managed without LRLT and 3 patients survived, and the survival rate was 50%. Other 9 patients received LRLT, and 2 of these 9 died with their complications after the transplantation. Thus the survival rate by LRLT in fulminant hepatic failure was 77.8%. Brain CT scan examination showed severe brain edema in a patient and the edema did not improve after LRLT. Another patient suffered from development of fungal infection in her lungs after LRLT. We suspected the presence of subclinical infection in the preoperation period. The recovery from brain edema and the existence of subclinical infection are mostly difficult to evaluate but are very important for obtaining a good output. These results suggest that LRLT is a promising procedure for treatment of fulminant hepatic failure but a close cooperation between physicians of internal medicine and transplantation surgery from preoperative management until postoperative period is necessary.

Acute Disease↗