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T Muto

Publications and source records attributed to T Muto.

At least 721 records · Page 40Linked to original sources
PubMedDate not supplied

Growth hormone inhibits apoptosis and up-regulates reactive oxygen intermediates production by human polymorphonuclear neutrophils.

BACKGROUND: Growth hormone (GH) regulates the immune and metabolic systems; however, the effects of GH on the functions and cell death of polymorphonuclear neutrophils (PMNs) are not well understood. Therefore, this study was designed to investigate the effects of GH on PMN apoptosis, reactive oxygen intermediates (ROI) production, CD16, and Fas expression. We also investigated the effects of GH on the functions of other circulating leukocytes (ie, monocytes and lymphocytes). METHODS: Venous blood was collected from healthy volunteers. Whole blood was washed and pretreated with GH (0 or 100 ng/mL) for 3 hours and then cultured for 0, 4, or 12 hours. PMNs in washed whole blood were analyzed by flow cytometry for cell death, phorbol myristate acetate-stimulated ROI production, CD16, and Fas expression at each time point. Morphologic features also were assessed. PMN apoptosis was confirmed by chromatin staining and DNA gel electrophoresis. RESULTS: GH inhibited PMN apoptosis at 12 hours of culture. GH enhanced ROI production by PMNs and monocytes throughout the 12-hour culture but had no effects on CD16 expression on PMNs. Furthermore, GH decreased Fas expression on PMNs at 4 hours of culture. However, there were no effects of GH on apoptosis of monocytes or lymphocytes for the duration of this experiment. CONCLUSIONS: GH pretreatment down-regulates Fas expression on PMNs, inhibits apoptosis, and up-regulates ROI production. GH pretreatment also increases monocyte ROI production. Although activated PMNs have potentially harmful aspects, our results suggest that GH may improve host defense, mainly through enhancement of the PMN functional life span.

Apoptosis↗
PubMedDate not supplied

Short-term hypothermic preservation of porcine hepatocyte spheroids using UW solution.

The feasibility of University of Wisconsin (UW) solution in short-term hypothermic preservation of porcine hepatocyte spheroids was investigated, because they have great potential in bioartificial liver (BAL) systems. Porcine hepatocyte spheroids preserved for 3 days expressed almost comparable levels of albumin secretion as those without preservation, during 8 subsequent days of recultivation in continuous rotational culture, whereas isolated single cells did not reorganize into spheroids and completely lost their function in recultivation. Although for 3-day-preserved spheroids, the albumin secretion was lowered immediately after recultivation (Days 0-2), it was completely restored to that of nonpreserved ones. The function was completely lost in recultivation for 7-day-preserved ones. These results demonstrate that reorganization into spheroids is effective in preventing the functional loss of porcine hepatocytes occurring in hypothermic preservation, and that spheroid formation should precede the preservation as long as spheroid culture is finally used in BAL systems. Also, porcine hepatocyte spheroids are shown to be satisfactory stored in UW solution up to 3 days without significant cellular or functional loss.

Adenosine↗
PubMedDate not supplied

A new bioartificial liver using porcine hepatocyte spheroids in high-cell-density suspension perfusion culture: in vitro performance in synthesized culture medium and in 100% human plasma.

A prototype of a bioartificial liver (BAL) based on suspension perfusion culture of porcine hepatocyte spheroids was developed at 150 ml scale. About 2% (4 x 10(9) cells) of whole human liver cells was immobilized. The cell density in the bioreactor was 2.7 x 10(7) cells/ml, which was almost comparable to that of presently developed packed-bed-type BALs. The bioreactor was perfused with culture medium while retaining spheroids. This was done using a rotating stainless filter (pore size 50 microm). In vitro 8-h perfusion experiments utilizing both synthesized culture medium and 100% human plasma demonstrated the spheroids in the bioreactor had almost the same functions on a unit/cell basis as those in small-scale rotational culture. This indicated that the functional deterioration often associated with scaling up had been minimized. Rapid spheroid aggregation and dysfunction in specific human plasma pool must be eliminated before clinical application, although this phenomenon seemed to be inherent to porcine hepatocyte-based BALs. This prototype shows promise in meeting present clinical demands by achieving maximal metabolic activities even in the short term.

Animals↗
PubMedDate not supplied

Partial sphingomyelinase deficiency with sea-blue histiocytosis and neurovisceral dysfunction.

A case of partial sphingomylinase deficiency with supranuclear vertical ophthalmoplegia, perceptive hearing loss and renal failure is reported. Extensive studies revealed sea-blue histiocytosis in bone marrow, delayed peripheral nerve conduction velocity, selective IgG and IgM deficiency, mild hepatosplenomegaly and testicular hypotrophy and retention. Although renal failure, perceptive deafness, immunoglobulin deficiency and testicular malformation are rare conditions in sphingomyelinase deficiency, this case mimicked to lipidosis reported by Neville. The association of congenital malformation and uremia might accentuate the symptoms.

Adolescent↗
PubMedDate not supplied

[A clinicopathological study of ruptured infectious aneurysms].

We investigated 952 consecutive autopsy cases between January 1990 and May 1994 to identify ruptured infectious aneurysms (IAs) of the aorta or iliac artery. Twenty patients (2.1%) died of artrial rupture, including 9 men and 11 women. The cause of rupture was IA in four cases (0.42%), atherosclerotic aneurysm (AA) in nine (0.95%), dissection (D) in six (0.63%), and aortoenteric fistula due to irradiation in one (0.11%). Infection of pre-existing aneurysms was considered to be AA rather than IA and the patient with aorto-enteric fistula was excluded from the study. Patients with IA were significantly older than other patients (IA: 85.8 +/- 4.3, AA: 80.2 +/- 4.1, and D: 77.7 +/- 5.0 years old), and were less frequently accompanied by leukocytosis than patients with AA, although this difference was not significant (11,100 vs 13,000). The four patients with IA consisted of one man and three women, all of whom died suddenly. Two patients had perforation in the atherosclerotic descending aorta and the other two had perforation in the atherosclerotic common iliac artery. Histological examinations revealed marked neutrophilic infiltration in all four cases, and bacterial colonies in three cases. In conclusion, IAs were not rare. Since they often cause sudden death, special attention should be given to elderly patients who develop infection.

Aged↗
PubMedDate not supplied

Endoscopic resection of adenoma of the minor papilla.

Tumors of the minor papilla of the duodenum are rare. We successfully and safely treated a 16 mm sessile adenoma of the minor papilla using endoscopic resection. Endoscopic retrograde cholangiopancreatography (ERCP) yielded a normal cholangiopancreatogram with blind termination of the duct of Santorini in the minor papilla. We recommend endoscopic resection and histological examination of the entire lesion for adenomas of the minor papilla in patients without pancreas divisum.

Adenoma↗
PubMedDate not supplied

Significance of K-ras codon 12 point mutation in pancreatic juice in the diagnosis of carcinoma of the pancreas.

The significance of K-ras codon 12 point mutation in pancreatic juice in the diagnosis of carcinoma of the pancreas is still unclear. The aim of this study was to evaluate the significance of K-ras codon 12 point mutation in pancreatic juice in the diagnosis of carcinoma of the pancreas. All of the 78 reports written from 1988 to 1996 on K-ras point mutation of carcinoma, mucin-producing tumors, and hyperplastic epithelia of the pancreas in both surgical or autopsy specimens and pancreatic juice are reviewed. As results, in surgical or autopsy specimens, K-ras mutation was found in 81% of ordinary duct cell carcinoma and in 53% of mucin-producing tumor of the pancreas; this mutation was also found in hyperplastic epithelia in chronic pancreatitis (7%) and in autopsy cases without pancreatic diseases. In pancreatic juice, K-ras mutation was found in 72% of ordinary pancreatic carcinoma and in 53% of mucin-producing tumor, respectively. In conclusion, most previous reports have indicated that K-ras mutation in pancreatic juice is useful for a diagnosis of pancreatic carcinoma. However, since K-ras gene mutation was also detected in non-tumorous lesions, the diagnosis of pancreatic carcinomas is not necessarily correct if it is based solely on the detection of K-ras mutation in pancreatic juice. Future studies should focus on analyzing the amino acid sequence of K-ras mutation or the combination of this mutation with other parameters such as tumor markers in pancreatic juice, to enhance its specificity and accuracy.

Carcinoma↗
PubMedDate not supplied

Transmesenteric hernia after laparoscopic-assisted sigmoid colectomy.

BACKGROUND AND OBJECTIVES: Laparoscopic-assisted surgery has been applied for a variety of colonic surgery. The objective of this paper is to demonstrate a possible and avoidable complication of laparoscopic colonic surgery. CASE PRESENTATION: A 47-year-old woman underwent gasless laparoscopic-assisted sigmoid colectomy. On the 20th postoperative day, she developed bowel obstruction. Decompression with a long tube failed to resolve the bowel obstruction. Open laparotomy was performed. Abdominal exploration revealed a loop of the small bowel incarcerated in the mesenteric defect caused by the previous operation. Adhesiolysis was performed, and the postoperative course was uneventful. DISCUSSION: Despite technical difficulty, complete closure of the mesentery after bowel resection is strongly recommended for prevention of transmesenteric incarcerated hernia after laparoscopic surgery.

Adenocarcinoma↗
PubMedDate not supplied

Intrahepatic interleukin-2 with chemotherapy for unresectable liver metastases: a randomized multicenter trial.

BACKGROUND/AIMS: A pilot study of Interleukin-2 (IL-2) with chemotherapy for unresectable colorectal liver metastases revealed a favorable response rate (76%). This prospective, randomized, multicenter study was conducted to evaluate the efficacy of this treatment protocol. METHODOLOGY: Over a period of 32 months, 46 patients with unresectable liver metastases were randomly assigned to 1 of 3 treatment groups: group A: chemotherapy alone, group B: chemotherapy plus high-dose, intermittent IL-2 (2.1 x 10(6) U twice weekly) or group C: chemotherapy plus low-dose, continuous IL-2 (7 x 10(5) U daily). Treatment continued for 4 weeks in the hospital and on an outpatient basis according to the clinical response. No crossover between treatment arms was permitted. RESULTS: IL-2 combined with chemotherapy produced a higher complete and partial response rate of 40% in group A, 60% in group B, and 78% in group C. Toxicity related to IL-2 included fever, chills, malaise, and eosinophilia. CONCLUSIONS: Hepatic arterial infusion of chemotherapy plus IL-2 resulted in an increased tumor response when compared with chemotherapy alone. To confirm the efficacy of this treatment protocol, we have started a large-scale, randomized, multi-institution trial.

Adult↗
PubMedDate not supplied

Three generations of hereditary chronic pancreatitis.

The patient was a 22 year-old male. Hereditary chronic pancreatitis was suspected as a diagnosis since his mother's uncle had been operated on for chronic pancreatitis 14 years previously at the age of 64 years and his mother had been operated on for chronic pancreatitis with calculi 5 years previously at the age of 40 years. Surgery was needed, since: 1) he had experienced abdominal pain for 8 years; 2) endoscopic retrograde cholangiopancreatography (ERCP) revealed a marked irregular dilatation in the main pancreatic duct and a marked irregular dilatation and protein plugs in the ductule of the tail of the pancreas; and, 3) pancreatic functional diagnostic (PFD) test examination showed a 75% decrease in exocrine function. If a surgical procedure had not been performed, the patient would likely have experienced calculi formation in the pancreas and a further decrease in exocrine function. Since the patient was very young and had many protein plugs in the dilated ductule of the tail of the pancreas, we decided to perform a spleen-preserving Puestow's procedure with removal of the tail of the pancreas. Clinical and pathological findings of hereditary pancreatitis are reviewed.

Adult↗
PubMedDate not supplied

Non-polypoid colorectal neoplasias: a multicentric study.

A total of 781 non-polypoid colorectal neoplasias harvested at 4 main Hospitals in Tokyo, Japan (n = 420) and at 4 different time-intervals at the Karolinska Hospital, Stockholm, Sweden (n = 361) were reviewed. By applying strict histologic definitions, the lesions were classified into adenomas with low grade dysplasia (LGD), with high grade dysplasia (HGD), intramucosal carcinomas (IMC) or submucosal carcinomas (SMC). Of the non-polypoid neoplastic lesions reviewed in Sweden, 82.8% (n = 299) had LGD. In Japanese patients only 42.6% (n = 179) had LGD (p < or = 0.001). On the other hand, as many as 42.4% (n = 178) of the non-polypoid lesions in Japanese patients had HGD, but only 14.1% (n = 51) of those in Swedish patients (p < or = 0.001). Whereas 15.0% (n = 63) of the non-polypoid neoplasias seen in Japan were IMC or SMC, only 3.0% (n = 11) of those seen in Sweden were IMC or SMC (p < or = 0.001). The cause(s) for these differences remains unclear. In Japan, however, a marked increased incidence of colonic cancer has been recorded in later years. Whether the "catching up phenomenon" by the Japanese with western colonic cancer incidence includes increased histologic aggressiveness of non-polypoid neoplastic polyps--as found in this survey--remains to be elucidated.

Adenoma↗
PubMedDate not supplied

Prognostic status of p53 gene mutation in canine mammary carcinoma.

BACKGROUND: The p53 gene mutations have been associated with the development of human breast and canine mammary neoplasms; breast carcinoma patients with alterations of p53 gene are considered to have a poor prognosis. Mammary carcinoma represents the most common malignant tumor in female dogs. However, the prognostic significance of p53 gene mutation in the dog has been unclear. STUDY DESIGN: The alteration in exons 5-8 of p53 gene in 69 canine mammary carcinomas were investigated by PCR-SSCP with direct sequence analysis and statistically analyzed to compare with other clinicopathological parameters including age, neuter, tumor size, stage, histology, p53 expression, recurrence and death from carcinoma. RESULTS: 12 out of 69 (17%) carcinomas showed p53 gene mutations. After a follow-up period of 30 months, multivariate regression analysis revealed that p53 gene mutation was only an independent risk factor for increased risk of the recurrence and death from mammary carcinoma. CONCLUSION: The p53 gene alterations might contribute to the prognostic status in canine mammary carcinomas, in a way comparable to that of human tumors.

Adenocarcinoma↗
PubMedDate not supplied

Primary intestinal obstruction complicated by persistent descending mesocolon.

Persistent descending mesocolon is an uncommon developmental anomaly which results from failure of fusion of the descending mesocolon with the posterior parietal peritoneum. It is asymptomatic in most cases and rarely causes intestinal obstruction. We report here a case of primary intestinal obstruction complicated by a persistent descending mesocolon. A 66-year-old man without prior laparotomy was admitted with a diagnosis of small bowel obstruction. Pre-operative investigation demonstrated a segmental jejunal stenosis and a persistent descending mesocolon as possible causes of the obstruction. Laparotomy showed that the cause of the obstruction was the jejunal stenosis, not the persistent descending mesocolon. The stenosis was resected, but correction of the anomaly was not performed. The patient made an uneventful recovery after the operation. From our limited experience, persistent descending mesocolon need not be surgically corrected when it is not considered to be the cause of obstruction and another definite cause co-exists.

Aged↗
PubMedDate not supplied

Carcinomas involving the esophagogastric junction.

In order to avoid confusion in categorizing malignant lesions for surgical treatment, a definition and criteria of carcinomas significantly involving the esophagogastric junction (ECJ-Ca) and those of gastric cardia less significantly involving the esophagogastric junction (eC-Ca) are proposed, devised as this study was from a practical viewpoint. A comparative analysis of carcinomas of these groups was carried out, the control group being those carcinomas situated mainly in the upper third segment of the stomach but not involving the esophagogastric junction (C-Ca). Carcinomas of these regions can be determined by the EGJ-Index (EGJ-I) calculated through the following formula: EGJ-Index = [( Length of the esophageal portion of the lesions)/(length of the of the esophageal portion + gastric portion of the lesion])x1,000. Thus lesions of these regions are easily and practically classified as follows: [I]: EGJ-Ca 250 less than or equal to EGJ-I less than or equal to 750, 59 cases; ( II]: eC-Ca 0 less than or equal to EGJ-I less than 250, 88 cases; [III]: C-Ca 0 = EGJ-I, 208 cases. We found these categories quite suitable for practical use.

Carcinoma↗
PubMedDate not supplied

Clinicopathological characteristics and surgical procedures for carcinoma of the papilla of Vater.

BACKGROUND/AIMS: In the present study, clinicopathological characteristics of carcinoma of the papilla of Vater and suitable operative procedures for treatment were investigated. MATERIAL AND METHODS: Sixty cases (40 male and 20 female) of resected carcinoma of the papilla of Vater were studied clinicopathologically. RESULTS: Among the patients, a polypoid type without ulceration and an ulcer-formation type, with regard to the gross appearance, were found in 37 cases and 23 cases, respectively. Submucosal invasion, invasion to the sphincter Oddi, pancreatic parenchymal invasion and lymph node involvement were found more frequently in the ulcer-formation type than in the polypoid type without ulceration. Postoperative survival curves revealed that the prognosis was poor when either lymph node involvement, invasion to pancreatic parenchyma or ulcer formation was found. Local resection was performed in seven cases, in all of whom carcinoma was found histologically in the cut surface of the tumor. This is easily explained by the fact that mucosal spread or interstitial infiltration was frequently found even in cases with carcinoma at a relatively early stage. CONCLUSIONS: Local resection for carcinoma of the papilla of Vater is inadequate as a curative resection, and pylorus-preserving pancreatoduodenectomy should be the treatment of choice for carcinoma of the papilla of Vater. However, since there were no differences between the postoperative survival curves of patients who underwent pancreatoduodenectomy or local resection, local resection may still be suitable for patients with other major diseases or a poor condition.

Adult↗
PubMedDate not supplied

A new method of duodenum-preserving subtotal resection of the head of the pancreas based on the surgical anatomy.

BACKGROUND/AIMS: Duodenum-preserving resection of the head of the pancreas has been performed for benign and, sometimes, malignant diseases of the pancreas. We propose a new procedure of duodenum-preserving subtotal pancreatectomy of the pancreas according to the precise anatomy of the pancreatoduodenal region, especially of the pancreaticoduodenal arteries which provide blood to the duodenum. MATERIAL AND METHODS: After a complete Kocher's maneuver is performed, the pancreas is cut above the portal vein and removed from the third portion of the duodenum, followed by the removal of the posterior surface of the pancreas head from a connective tissue membrane. The main pancreatic duct is identified at its junction with the terminal portion of the bile duct from the posterior surface of the head of the pancreas and is cut at the junction. The pancreas is cut in the line of the ASPD. This line is almost the same as the left side of the common bile duct. The ASPD and the common bile duct should be preserved in this procedure. RESULTS: The reason for leaving part of the pancreas between the duodenum and the anterior superior pancreaticoduodenal artery and the common bile duct is that the artery toward the papilla of Vater runs along the right side of the common bile duct and would be difficult to be preserved with the removal of this part of the pancreas. The most important technique of this procedure is in keeping the connective tissue membrane of the posterior surface of the pancreas intact so as to preserve pancreaticoduodenal arteries and veins, because all the pancreaticoduodenal arteries and veins are situated on this membrane. Complete Kocher's maneuver should cause no problem in this procedure. CONCLUSIONS: Benign lesions as well as low-grade malignancy of the head of the pancreas may possibly be the indication of this procedure.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

Flat serrated adenomas of the colorectal mucosa in Japanese patients.

While reviewing the histological sections of 319 flat colorectal polyps at three different Hospitals in Tokyo, 7 cases of flat serrated adenomas were found. Flat serrated adenomas differ histologically from flat tubular adenomas. In the former the dysplastic cells are found initially at the lower part of the crypts of Lieberkuhn, and the epithelium of the sides of those crypts have serrated infoldings without dysplastic cells. In flat tubular adenomas, however, the dysplastic cells are initially found in the upper part of straight crypts (i.e. without epithelial infoldings). Six of the 7 serrated adenomas had low grade dysplasia (LGD) and the remaining one high grade dysplasia (HGD). Atypical mitosis were present in the dysplastic epithelium of serrated adenomas. Depending upon the topographic distribution of the dysplastic epithelium within the crypts flat serrated adenomas were divided into Type I, where the dysplastic epithelium was limited to the lower half of the serrated crypts, and Type II where the dysplastic epithelium was present even in the superficial half of the serrated crypts. Of the 7 serrated adenomas, 3 were Type I and the remaining 4 Type II lesions. The dysplastic epithelium seemed to have originated at the base of the crypts and progressed upwards, replacing the scalloped, serrated epithelium. Flat serrated adenomas appeared as benign lesions upon endoscopy (their pit pattern being identical to flat hyperplastic polyps), but in a previous survey of Swedish patients 3 of 47 flat serrated adenomas had invasive adenocarcinoma (i.e. with submucosal extension). Whether serrated adenomas evolved into invasive carcinoma in the Japanese should be assessed in a larger series of cases.

Adenoma↗