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T Honma

Publications and source records attributed to T Honma.

At least 37 records · Page 2Linked to original sources
PubMed2001

Activated platelets in ulcerative colitis enhance the production of reactive oxygen species by polymorphonuclear leukocytes.

BACKGROUND: Although the number of activated platelets increases in the peripheral blood of patients with inflammatory bowel disease (IBD), the role of activated platelets in the polymorphonuclear leukocytes (PMN)-mediated mucosal injury in IBD remains unclear. In the present study, we used luminol-enhanced chemiluminescence (LCL) to examine the influence of platelets from patients with ulcerative colitis (UC) on the production of reactive oxygen species (ROS) by circulating PMN. METHODS: The proportion of P-selectin-positive activated platelets was determined using flow cytometry. PMN from patients with UC and normal controls were stimulated using phorbol 12-myristate 13-acetate with or without autologous platelets, anti-P-selectin monoclonal antibody and thrombin. Indicator PMN from a normal volunteer were stimulated using heterologous platelets from UC patients and normal controls, and LCL signals were registered every 60 sec for 240 min. RESULTS: The proportion of activated platelets was significantly increased in IBD patients. The level of ROS production by PMN did not significantly differ between UC patients and normal controls in the absence of a platelet-PMN interaction. Platelets from UC patients enhanced the amount of ROS produced by indicator PMN significantly more than those from normal controls. This effect was partly diminished by anti-P-selectin monoclonal antibody. CONCLUSIONS: Platelet activation in UC might be responsible for the secondary activation of PMN, which could account for the increase in PMN-mediated tissue injury associated with UC.

Adult↗
PubMed2001

A new peritoneal dissemination model established from the human pancreatic cancer cell line.

We established a new cell line, HPC-3P4a, with high peritoneal disseminated potential in nude mice. HPC-3P4a was derived from a human pancreatic carcinoma cell line (HPC-3) that had low capacity for peritoneal dissemination. HPC-3P4a developed peritoneal dissemination in 10 of 11 (90.9%) cases, whereas parental HPC-3 developed peritoneal dissemination in one of six (16.7%) cases. The metastatic foci in the peritoneum showed essentially the same histologic appearance of parental involvement. The tumorigenicity, motility, and adhesive activity of HPC-3P4a to the extracellular matrix were stronger than were those of the HPC-3. In FACS analysis, HPC-3P4a significantly increased the expression of alpha6 and alpha(v)beta5 integrins, while it decreased alpha2 integrin, hCD44H, and hCD44v 10, as compared with HPC-3. The VEGF production of HPC-3P4a was significantly lower than that of HPC-3. Analysis of gene macroarrays showed a variety of cytokines, interleukin, and other immunomodulatory, and their receptors were up-regulated and down-regulated on an mRNA level in HPC-3P4a cells, compared with HPC-3 cells. Intrasplenic injection of HPC-3P4a produced no liver metastasis. We named our original highly liver metastatic cell line HPC-3H4 (previously reported). This HPC-3H4 cell was established by repeated intrasplenic injection from parental cell HPC-3; thus, it developed high liver metastasis. Moreover, HPC-3H4 developed peritoneal dissemination by intra-abdominal injection. In contrast, HPC-3P4a did not develop liver metastasis by intrasplenic injection. These findings are very interesting and might suggest that the process of hematogenous metastasis differed from that of peritoneal dissemination. Thus, this cell line may be useful for investigating the mechanism of peritoneal dissemination in human pancreatic cancer.

Adenocarcinoma↗
PubMed2001

Pharmacokinetics of granisetron in adults and children with malignant diseases.

Granisetron (GRN) is widely used for patients with various cancers who suffer from chemotherapy-induced vomiting and nausea. The, pharmacokinetics of GRN has not been fully evaluated in such patients, however, and its dosage regimen is still controversial. In this study, we determined GRN levels in serum and urine from lung cancer patients and children suffering from cancer after intravenous infusion. In lung cancer patients, the interindividual variations in t(1/2beta), area under the concentration-time curve (AUC), and Vd(beta) were relatively smaller than expected from previous reports on healthy subjects, while t(1/2beta) was prolonged more than 5-fold in healthy subjects. Urinary excretion of unchanged GRN in lung cancer patients was ca. 15% of dose, consistent with previous reports, and one individual demonstrated an even higher urinary excretion (ca. 45%). The pharmacokinetic parameters of GRN in child cancer patients varied markedly among individuals, and some child patients had smaller t(1/2beta) than adult patients. In these cases, GRN should be administered at shorter intervals. These results suggested that a pharmacokinetic study of GRN was necessary for planning a dosage regimen and managing chemotherapy-induced vomiting and nausea.

Adolescent↗
PubMed2001

Adenosquamous carcinoma of the colorectum: report of two cases.

Adenosquamous carcinomas of the colorectum are rare neoplasms. Our experience with two cases is presented in this paper. One patient, who complained of bloody stool, was found to have adenocarcinoma in the sigmoid colon. He received a laparoscopy-assisted sigmoidectomy. The histological examination revealed that the tumor was adenosquamous carcinoma. To date, he has survived six months post operatively without evidence of recurrence. The other patient, who complained of anal bleeding, was found to have rectal adenocarcinoma and received a low anterior resection. Histological examination revealed that the tumor was an adenosquamous carcinoma. He remains alive, with no evidence of recurrence, nine years post operatively. Both cases showed paracolic lymph node metastasis. Because of its very low incidence, the histogenesis, malignancy and prognosis of this disease remain unclear. Thus, further clinical and histological study of this disease entity is required.

Carcinoma, Adenosquamous↗
PubMed2001

[Risk factor for cerebral hemorrhage for the patient with lacunar infarction: investigation of 5 cases associated with both of symptomatic hemorrhagic and ischemic strokes].

BACKGROUND AND PURPOSE: Microangiopathy is regarded as an important cause of intracerebral hematoma(ICH) and lacunar infarction. Dot-like low intensity spots on T2-weighted echo planar image(EPI) have been regarded as hemosiderin deposit associated with microangiopathy. However, clinical significance of dot-like hemosiderin spot(dotHS) is still debated. Therefore, we analyzed the number of dotHS on EPI of symptomatic lacunar infarction associated with ICH. METHODS: To investigate how the dotHS or risk factors contributed to hemorrhagic strokes for patients with lacunar infarction, the number of dotHS and various risk factors were made a comparison between 20 cases with symptomatic lacunar infarctions(lacunar group) and 5 cases with both symptomatic lacunar infarction and symptomatic ICH(complicated group). In addition to EPI, fluid attenuated inversion recovery image, and T1- and T2-weighted MR images were performed for differential diagnosis of dot HS. RESULTS: EPI demonstrated that asymptomatic ICH was significantly more frequent in complicated group (60%) than in lacunar group(10%), and dotHS were significantly more frequent in complicated group(100%) than in lacunar group(50%). The number of dotHS of complicated group was 14.6 +/- 4.3, which was significantly larger than that of lacunar group(4.1 +/- 9.2). No significant difference between two groups were founded in other risk factors including hypertension, diabetes mellitus, hyperlipidemia, and smoking. CONCLUSION: These results suggested that dotHS was one of the risk factors for ICH for patients with symptomatic lacunar infarction, and an increasing number of dotHS was one of the predictive factors of symptomatic and/or asymptomatic ICH.

Aged↗
PubMed2001

[Pulmonary hyalinizing granuloma with massive infiltration of lymphocytes].

A 39-year-old man was admitted to our hospital for examination of multiple nodules and infiltrates on a chest radiograph. His chest HRCT revealed multiple nodules with or without thick- or thin-walled cavities. Specimens obtained by video-assisted thoracoscopic biopsy showed bundles of hyalinized collagen fibers, some of which contained accumulated plasma cells in the center. The nodules were surrounded by massive lymphoid cells which formed germinal centers. These findings are compatible with pulmonary hyalinizing granuloma. The lymphoid cells looked uniform in some areas and had infiltrated along the bronchioles and small vessels and into the intralobular septa in a manner resembling pulmonary lymphoma or pseudolymphoma. The findings suggested that pulmonary hyalinizing granuloma may overlap pulmonary lymphoma. The disease has shown no progression for four years although no treatment has been given.

Adult↗
PubMed2000

Morphometric study of the sphincter of oddi (hepatopancreatic) and configuration of the submucosal portion of the sphincteric muscle mass.

The sphincter of Oddi (SO) hepatopancreatic sphincter from 114 Japanese adults, especially the sphincteric muscle mass lying in the duodenal mucosal layer (the submucosal portion of the SO: SMSO), was measured macroscopically under a binocular microscope. The SMSO was classified into two types according to shape. The horizontal type (95/114) usually displayed a rod-like shape (6.0 mm at average diameter at the root) directed toward the anus and was situated on the duodenal muscle wall with the papillary orifice at or near the tip (anal side) of the SMSO. The horizontal type SMSO followed the underlying muscle wall widely ranging from 5.0 mm to 17.9 mm length (9.8 mm at average) and was attached to the wall by the loose connective tissue along the entire length. In the horizontal type, the extramural portion (the portion penetrating and outside of duodenal muscle of the SO) of the SO was very small. The vertical type (19/114) erected on the muscle wall vertically into the lumen of the duodenum. The average length and average maximum diameter of the vertical type were 6.0 mm and 6.2 mm, respectively. The extramural portion of the SO was thicker and tighter in the vertical type, which suggested that endoscopic sphincterotomy might preserve the length of the SO longer than endoscopic papillary balloon dilation (EPBD). Of the individuals in our study, 18% (19/114) had SO diameters <5 mm, a finding that may have implications for selection of balloon size in EPBD.

Aged↗
PubMed2000

CD spectra of solid-state samples

Solid-state CD spectroscopy can provide valuable information on conformation, intermolecular interactions, including chirality induction, and enantioselective reactions which occur specifically in the solid state. The technique can, however, suffer from serious artifacts. Some examples of solid-state CD are given and potential artifacts are discussed. Copyright 2000 Wiley-Liss, Inc.

Journal Article↗
PubMed2000

FD-891, a structural analogue of concanamycin A that does not affect vacuolar acidification or perforin activity, yet potently prevents cytotoxic T lymphocyte-mediated cytotoxicity through the blockage of conjugate formation.

FD-891 belongs to a group of 18-membered macrolides, and is a structural analogue of a specific inhibitor of vacuolar type H+-ATPase, concanamycin A (CMA). In our previous work, we have shown that CMA specifically inhibits perforin-dependent cytotoxic T lymphocyte (CTL)-mediated cytotoxicity through the degradation and inactivation of perforin, although CMA does not affect Fas ligand (FasL)-dependent cytotoxicity. Here, we show that FD-891 potently prevents not only perforin-dependent but also FasL-dependent CTL-mediated killing pathways by blocking CTL-target conjugate formation. In contrast to CMA, FD-891 was unable to inhibit vacuolar acidification and only slightly decreased the perforin activity in lytic granules. FD-891 blocked granule exocytosis in response to anti-CD3, mainly owing to the lack of CTL binding to immobilized anti-CD3. The conjugate formation was markedly inhibited only when effector cells were pretreated with FD-891. Consistent with these observations, fluorescence-activated cell sorter (FACS) analysis for cell surface receptors revealed that FD-891 significantly reduced the expression of the T-cell receptor (TCR)/CD3 complex. These data suggest that the blockage of conjugate formation and subsequent target cell killing might be at least partly owing to FD-891-induced down-regulation of the TCR/CD3 complex.

Animals↗
PubMed2000

The role of endoscopic retrograde cholangiopancreatography in infants with cholestasis.

BACKGROUND/PURPOSE: Endoscopic retrograde cholangiopancreatography (ERCP) was assessed in the diagnosis of cholestatic liver disease in infants. METHODS: ERCP was performed in 50 infants who had prolonged cholestasis. Their ages ranged from 25 to 274 days (mean, 69 days), and their weight ranged from 2.6 to 6.7 kg (mean, 4.7 kg). Incomplete visualization of the biliary tree or visualization of only the pancreatic duct was followed by exploratory laparotomy. In those in whom the biliary tree was visualized completely, the caliber of the bile duct was compared with that of the pancreatic duct. RESULTS: ERCP was completed in 43 patients (success rate, 86%) without complications. In the 7 patients in whom ERCP failed, 6 had biliary atresia (BA) diagnosed by exploratory laparotomy. The other patient had congenital biliary dilatation (CBD). In 29 of the 43 patients, the biliary tree was seen partially or only the pancreatic duct was visualized. These patients had BA diagnosed by laparotomy. Complete visualization of the biliary tree was obtained in 14 patients. Of these, 9 had neonatal hepatitis (NH), 2 had a paucity of intrahepatic bile ducts (PIBLD), and 3 had CBD. In all of the patients with NH, cholestasis improved spontaneously. The 2 patients with PIBLD had biopsy-proven disease. The caliber of the bile duct was larger than that of the pancreatic duct in NH. This relationship was not observed in PIBLD. CONCLUSIONS: ERCP is safe in infants. It is useful in the diagnosis of prolonged cholestasis.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed2000

Nuclear translocation of beta-catenin in colorectal cancer.

Post-translational stabilization of beta-catenin through mutation of the adenomatous polyposis coli (APC) gene has been proposed as an early step in colorectal carcinogenesis. Beta-catenin may translocate from the cytoplasm to the nucleus, where it might serve as a transcriptional factor to stimulate tumour formation. We investigated intracellular localization of beta-catenin in sporadic colorectal adenomas and cancers as well as familial adenomatous polyposis (FAP). Nuclear over-expression of beta-catenin was observed in 35% (7/20) of intramucosal cancers and 42% (23/55) of invasive cancers but was not seen in any adenomas from sporadic or FAP cases. Cytoplasmic beta-catenin in adenomas was significantly higher than that of normal mucosa in both sporadic and FAP cases. The cytoplasmic intensity index of cancers was significantly higher than that of sporadic adenomas, but the index was not correlated with nuclear expression in cancers. These findings suggest that nuclear translocation of beta-catenin is involved in development of intramucosal cancer rather than adenoma, independent of APC mutations. Cytoplasmic accumulation of beta-catenin may occur in adenomas, but it remains to be determined whether this is a cause or a consequence of colorectal cancer.

Adenoma↗
PubMed2000

Fas/Fas ligand expression and characteristics of primed CD45RO+ T cells in the inflamed mucosa of ulcerative colitis.

BACKGROUND: Chronic immune activation in the colon is characteristic of ulcerative colitis (UC). Fas/Fas ligand (FasL) system is a mechanism responsible for activation-induced cell death (AICD), which maintains homeostasis within the immune system. Thus, Fas/FasL expression on activated colonic T cells of UC patients, as well as the susceptibility of such T cells to AICD was investigated in order to determine the role of activated colonic T cells in the long lasting inflammation in UC. METHODS: Fas, FasL, and CD45RO expression on peripheral blood and colonic T cells of UC patients were assayed by flow cytometry. Apoptosis of colonic T cells induced by anti Fas antibody was assessed using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay. RESULTS: The majority of colonic T cells expressed both CD45RO and Fas in the colonic mucosa, a situation that was quite different from that in the peripheral blood. The number of CD45RO+CD8+ and Fas+CD8+ T cells was significantly lower in UC patients than the controls, unlike the number of Fas+CD4+ T cells. In contrast, the number of both CD45RO+CD4+ and CD45RO+CD8+ T cells in UC mucosa expressing FasL was significantly higher than in the controls. While Fas mediated apoptosis of CD45RO+CD8+ T cells was higher in UC patients than the controls, the number of apoptotic CD45RO+CD4+ T cells from UC mucosa was not. CONCLUSIONS: In UC patients, CD45RO+CD4+ T cells are less sensitive to apoptotic signals mediated by Fas. These phenomena may contribute to the pathogenesis of UC.

Adult↗
PubMed2000

The striking effect of hyperbaric oxygenation therapy in the management of chronic idiopathic intestinal pseudo-obstruction.

Chronic idiopathic intestinal pseudo-obstruction is one of the disorders that is most refractory to medical and surgical treatment. Even when patients are given nutritional support, including total parenteral nutrition, obstructive symptoms seldom disappear. We report a case of chronic idiopathic intestinal pseudo-obstruction, due to myopathy, in which hyperbaric oxygenation therapy was strikingly effective. The presence of myopathy was histologically confirmed on the surgically resected jejunal specimen. Hyperbaric oxygenation resulted not only in relief of the patient's obstructive symptoms but also in a rapid decrease of abnormally accumulated intestinal gas. At last, he could resume oral intake without any critical adverse effects. These observations strongly suggest that hyperbaric oxygenation can be an effective therapy in the management of chronic idiopathic intestinal pseudo-obstruction.

Chronic Disease↗
PubMed2000

Influence of 2-bromopropane on reproductive system--short-term administration of 2-bromopropane inhibits ovulation in F344 rats.

The present study was performed to investigate the toxic effects of 2-bromopropane (2BP) on the female reproductive system. Female F344 rats were administered 2BP (500 or 1000 mg/kg, i.p.) at intervals of 2 or 3 days for 15-17 days. The body weights were measured and estrous stages were observed throughout the experimental period. Ovulation, organ weights, ovarian histology, and blood biochemistry were investigated on the terminal day of the experiment. Uterine weights in rats treated with 2BP were significantly lower than those in control animals. Body, liver, kidney, and adrenal weights in 2BP-treated rats showed no significant differences from control values. 2BP treatment prolonged estrous cycles and decreased the number of ovulated ova in spontaneous ovulation. In addition, histological examinations showed that the preovulatory follicles in the ovary were altered markedly in 2BP groups. These results show that even in short-term treatment, 2BP injured the ovary, particularly the preovulatory follicles. It appears that these damages of the preovulatory follicles induced by 2BP reduced the numbers of spontaneously ovulated ova in female F344 rats.

Amylases↗