Biomedical subjects

H Ban

Publications and source records attributed to H Ban.

At least 19 recordsLinked to original sources

PubMed2007

Loss of MUC2 expression correlates with progression along the adenoma-carcinoma sequence pathway as well as de novo carcinogenesis in the colon.

AIMS: We have previously demonstrated links between clinicopathological findings and phenotypes using several gastric and intestinal phenotypic markers in stomach and pancreatic cancers. However, the clinicopathological significance of the phenotype and Cdx2 expression has hitherto remained unclear in colorectal carcinogenesis. METHODS AND RESULTS: We examined the correlation between gastric and intestinal phenotypic expression in 91 primary early carcinomas of the colon. MUC2 expression demonstrated a significant decrease from tubular/tubulovillous adenomas with moderate atypia, through intramucosal carcinomas, to cancers with submucosal invasion (P<0.0001). Intramucosal de novo carcinomas (flat type carcinomas without adenomatous components) exhibited a greater decrease of MUC2 than intramucosal lesions with adenomatous components. Expression of MUC5AC also decreased significantly with progression according to the tubular/tubulovillous adenoma-carcinoma sequence, carcinomas with villous adenomatous components having a higher level compared with their tubular adenomatous counterparts, suggesting differences in the pathway of malignant transformation. Cdx2 nuclear expression was maintained in all of the adenomas and early carcinomas examined. CONCLUSIONS: Our data suggest that the reduction of MUC2 expression may be associated with the occurrence and progression of colorectal carcinomas in both adenoma-carcinoma sequence pathway and de novo carcinogenesis. Tumor-suppressive effects of Cdx2 may be preserved during early stages of colorectal carcinogenesis.

Adenocarcinoma↗

PubMed2007

Gastric and intestinal phenotypic correlation between exocrine and endocrine components in human stomach tumors.

We have previously suggested that an origin of a stomach cancer is from a progenitor cell specializing toward exocrine cell (Exo-cell) lineages. To clarify whether our hypothesis is correct or not, we analyzed the expression of Exo-cell and endocrine cell (End-cell) markers in a series of lesions for comparison. We evaluated chromogranin A (CgA) expression in 37 early and 73 advanced stomach cancers, in 30 stomach adenomas, in 8 carcinoid tumors, and in 4 endocrine cell carcinomas (ECCs) with assessment of gastric and/or intestinal (G/I) phenotypes in both Exo-cell and End-cell by immunohistochemistry. CgA expression was observed in 10.8% of the early and 16.4% of the advanced stomach cancers, respectively. The End-cell G/I phenotypes were in line with the Exo-cell counterparts in the CgA-positive stomach cancerous areas, and there was strong association between Cdx2 expression and the intestinal End-cell markers. All of the adenoma cases had the intestinal Exo-cell phenotypic expression, with the positive link between Exo-cell and End-cell G/I phenotypes. All stomach carcinoids had CgA expression but no expression of Exo-cell markers. In conclusion, most stomach cancers might develop from a progenitor cell specializing towards Exo-cell lineages, but some cases possessed both Exo-cell and End-cell markers with maturely differentiated phenotypes. In such cases, Exo-cell and End-cell phenotypes were found to correlate strongly, suggesting the possibility of histogenesis from "cancer stem cells".

Adenocarcinoma↗

PubMed2000

Molecular cloning of a novel importin alpha homologue from rice, by which constitutive photomorphogenic 1 (COP1) nuclear localization signal (NLS)-protein is preferentially nuclear imported.

Nuclear import of proteins that contain classical nuclear localization signals (NLS) is initiated by importin alpha, a protein that recognizes and binds to the NLS in the cytoplasm. In this paper, we have cloned a cDNA for a novel importin alpha homologue from rice which is in addition to our previously isolated rice importin alpha1a and alpha2, and we have named it rice importin alpha1b. In vitro binding and nuclear import assays using recombinant importin alpha1b protein demonstrate that rice importin alpha1b functions as a component of the NLS-receptor in plant cells. Analysis of the transcript levels for all three rice importin alpha genes revealed that the genes were not only differentially expressed but that they also responded to dark-adaptation in green leaves. Furthermore, we also show that the COP1 protein bears a bipartite-type NLS and its nuclear import is mediated preferentially by the rice importin alpha1b. These data suggest that each of the different rice importin alpha proteins carry distinct groups of nuclear proteins, such that multiple isoforms of importin alpha contribute to the regulation of plant nuclear protein transport.

Amino Acid Sequence↗

PubMed1998

Abdominal wall plasty for a premature infant with congenital diaphragmatic hernia.

This paper reports a premature infant with a congenital diaphragmatic hernia (CDH) who underwent an abdominal wall plasty to enlarge the abdominal cavity, one of twin infants born at 32 weeks weighing 1,255 g. After stabilization, the herniated viscera were reduced from the pleural cavity and the abdominal wall muscle and skin layers were replaced by a Gore-tex patch without closure of the diaphragmatic defect. Respiratory and circulatory conditions were stable during the perioperative period. Postoperatively, a roentogenogram showed expansion of the lung. However, his condition deteriorated 24 h after surgery, triggered by intratracheal suction, and he died on the 4th day of life despite the use of high-frequency oscillation, catecholamines, and vasodilators. Postmortem examination showed severely hypoplastic lungs. Abdominal wall plasty may be a less invasive initial procedure, however, further studies, such as comparison with the standard method or conservative management, are needed using a large clinical group or animal models to justify the usefulness of this procedure.

Abdominal Muscles↗

PubMed1998

Transumbilical resection and umbilical plasty for patent omphalomesenteric duct.

This paper describes a transumbilical resection and umbilical plasty for treatment of a patent omphalomesenteric duct (POMD). In a newborn infant with a POMD, a skin incision was made circumscribing the mucocutaneous junction of the protruded duct. The duct was completely extirpated with a wedge resection of the connection to the intestine and an umbilical plasty was performed. The postoperative appearance was excellent. It appears that transumbilical resection and umbilical plasty may be a satisfactory operation for POMD.

Humans↗

PubMed1998

Portal hypertensive enteropathy in biliary atresia.

This paper describes a rare case of biliary atresia (BA) in which massive postoperative bleeding developed due to portal hypertensive enteropathy. A 15-year-old boy had been doing well after Kasai's operation for BA. At around the age of 6 years he developed recurrent episodes of esophageal variceal bleeding and underwent esophageal transection, splenectomy, sclerotherapy, and embolization of the left gastric vein. At the age of 15 years he suddenly developed abdominal pain, hematemesis, and massive tarry stools. His hemoglobin level was 6.3 g/dl. Endoscopy showed several small, polypoid lesions in the jejunum beyond Treitz' ligament. The source of the bleeding was one of these lesions located in the proximal jejunojejunostomy of the Roux-en-Y loop. Because he had repeated episodes of melena, he underwent partial resection of the jejunum under endoscopic guidance. He has since been free of gastrointestinal (GI) bleeding. From this experience, we conclude that the polypoid lesions of an enteropathy may be a cause of massive GI bleeding in the postoperative portal hypertension of BA.

Adolescent↗

PubMed1995

User interface design and evaluation for electronic medical record system.

A user interface for an electronic medical record system (EMRS) is proposed. A pen-based device adopted for data input and the GUI windows layout simulate conventional paper forms, so that doctors can quickly grow accustomed to the EMRS. A comparison study shows the proposed interface does not significantly delay the examination, even when used in hospitals with many outpatients.

Ambulatory Care↗

PubMed1994

Effects of naftidrofuryl oxalate, a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus.

We investigated the effects of age and nafidrofuryl oxalate (Naftidrofuryl), a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [3H]Quinuclidinyl benzilate (QNB), [3H]cyclohexyl-adenosine (CHA), [3H]MK-801, and [3H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-D-aspartate (NMDA), and gamma-aminobutyric acid-A (GABAA) receptors, respectively. [3H]PN200-110 labeled L-type Ca2+ channels. [3H]Forskolin, [3H]cyclic adenosine monophosphate (cAMP), [3H]phorbol 12,13-dibutyrate (PDBu), and [3H]inositol 1,4,5-triphosphate (IP3) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP3 receptors, respectively. Approximately 20% reductions in [3H]QNB, [3H]forskolin, and [3H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [3H]CHA, [3H]MK-801, [3H]muscimol, [3H]PN200-110, [3H]cAMP, and [3H]IP3 binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications.

Adenosine↗

PubMed1994

Effects of naftidrofuryl oxalate, a 5-HT2 antagonist, on neuronal damage and local cerebral blood flow following transient cerebral ischemia in gerbils.

Effects of naftidrofuryl oxalate (naftidrofuryl), a 5-HT2 antagonist, on neuronal damage and local cerebral blood flow was examined in a gerbil model of transient forebrain ischemia. Effect of ketanserin tartrate (ketanserin), another 5-HT2 antagonist, on neuronal damage was also examined. Pretreatment with naftidrofuryl or ketanserin prevented hippocampal CA1 neuronal loss after 5 min of transient ischemia. Naftidrofuryl did not improve hippocampal blood flow during and 1 h after transient ischemia determined by [14C]iodoantipyrine autoradiography but increased blood flow in the caudate-putamen 1 h after transient ischemia. The results show that: (1) the 5-HT2 antagonists protect against hippocampal CA1 neuronal damage; and (2) the protective effect of naftidrofuryl may not be caused by a hemodynamic mechanism but by a direct inhibitory neuromodulation via 5-HT2 antagonistic action.

Animals↗

PubMed1993

Increased level/dose ratio of amphotericin-B in premature infants with renal failure.

We introduced continuous intravenous infusion of amphotericin-B (AMPH-B) to extremely low birthweight (ELBW) infants (< 1000 g) with or without renal failure as a single agent for treating definite or probable systemic candidiasis. The species of Candida isolated from blood or tracheal aspirate or urine were C. albicans in seven infants, C glabrata in two, C. tropicalis in one and C. parapsilosis in one. The minimal inhibitory concentrations (MIC) of AMPH-B required against these isolates were less than 0.2 micrograms/mL except for that against one strain of C. albicans (0.78 microgram/mL). Serum AMPH-B levels were 0.31-0.78 (0.51 +/- 0.14) micrograms/mL when doses of 0.2-0.55 (0.32 +/- 0.11) mg/kg per day were being administered. The serum level was higher than the MIC of each isolate in all but one infant who died of disseminated intravascular coagulation and Candida pneumonia. Another infant died of congenital heart disease. The other nine infants survived. The serum level showed no correlation with the daily dose. The ratio of the serum level to the daily dose (L/D ratio) showed a significant correlation to serum creatinine (r = 0.787) and the linear regression curve followed the equation: L/D ratio = 0.223 x serum creatinine + 1.11 (P < 0.01). Few adverse effects due to AMPH-B were noted. Our data may give a simple reference to serum AMPH-B levels during continuous intravenous infusion from the dose and the serum creatinine level.

Acute Kidney Injury↗

PubMed1991

The possible involvement of tetrodotoxin-sensitive ion channels in ischemic neuronal damage in the rat hippocampus.

To determine the role of tetrodotoxin-sensitive ion channels in post-ischemic selective neuronal death, the effect of tetrodotoxin on ischemia-induced brain cell injury was studied in rats. The animals were subjected to 20 min of cerebral ischemia in a four vessels occlusion model. Thirty min before ischemia, tetrodotoxin at a dose of 10(-7) or 10(-6) M was topically applied into the hippocampal CA1 subfield. Morphological changes in the CA1 subfield were evaluated 7 days after ischemia and compared with those of a vehicle-injected group. The average cell density of CA1 pyramidal neurons ipsilateral to the injection (cells/mm, mean +/- S.E.M.) was 27 +/- 7 (n = 6) in the vehicle-treated group, and 56 +/- 13 (n = 6) and 83 +/- 17 (n = 6) in the group treated with tetrodotoxin at doses of 10(-7) and 10(-6) M, respectively. Tetrodotoxin mitigated the ischemic hippocampal neuronal damage in a limited but dose-dependent manner. This suggests that activation of tetrodotoxin-sensitive ion channels might contribute to the process of the ischemic neuronal damage.

Animals↗

PubMed1991

Rationale for frequency and dose of administration in gestrinone therapy for pelvic endometriosis in the experimental model of rabbit uterus.

1. Gestrinone has been used for treatment of pelvic endometriosis, in doses of 2.5 mg twice a week. This study is designed to clarify it from the dynamics of sex steroid receptors in rabbit uterus. 2. Four different regimens were scheduled, namely daily 1 microgram estradiol-17 beta (E2, consistent with endogenous level of women) for 3 days, and together with either 30, 60 (consistent with 2.5 microgram of clinical dose) or 120 microgram(s) gestrinone, in single dose or with 20 microgram(s) gestrinone daily (divided dose in single 60 microgram(s) gestrinone administration) for 3 days. Receptors for estrogen (ER, type I and II) or progestin (PR) were determined by charcoal adsorption in cytosol and KCl extract, or sedimentation in non-KCl extractable fraction, using [3H]E2 or [3H]promegestone respectively. 3. Gestrinone decreased total ER (type I and II) levels, dose-dependently, except the case of 20 micrograms gestrinone daily in ER type II. Total ER type I level did not return to the pre-level until 3 days only after 120 microgram(s) gestrinone administration. Total ER type II level was decreasing in 3 days after 30, 60 or 120 micrograms gestrinone therapy. Total PR level was decreased in the order of strength: 120 micrograms gestrinone greater than 60 micrograms gestrinone greater than 30 microgram gestrinone greater than 20 micrograms gestrinone in group, and the recovery was not obtained until 72 hr only after 120 micrograms gestrinone therapy. The uterine weight was decreasing with the same strength in 3 days of the therapy independently upon the regimen. 4. In conclusion, gestrinone dose of 60 micrograms (2.5 mg of clinical dose) every 3 days is considered to be effective for anti-steroid action in sex steroid receptor dynamics in the rabbit uterus, contributing to the rationale for gestrinone treatment of pelvic endometriosis.

Animals↗

PubMed1987

Inhibitory effect of polymyxin B on catecholamine secretion from cultured bovine adrenal medullary cells.

Incubation of cultured bovine adrenal medullary cells with 12-O-tetradecanoylphorbol-13-acetate (TPA), an activator of Ca2+/phospholipid-dependent protein kinase (protein kinase C), was associated with increased secretion of catecholamine (CA) from the cells. Polymyxin B (PMB, 30-300 microM), a preferential inhibitor of protein kinase C, inhibited the TPA-induced secretion of CA. PMB also inhibited CA secretion induced by other secretagogues, the Ca2+ ionophore ionomycin (10 microM), 56 mM K+ or acetylcholine (ACh). Ionomycin, 56 mM K+ or ACh increased the concentration of intracellular free Ca2+ ([Ca2+]i) (measured using the fluorescent calcium indicator quin2), whereas TPA did not increase [Ca2+]i. PMB blocked the increase in [Ca2+]i induced by 56 mM K+ or ACh at concentrations similar to those inhibiting the secretion of CA. In contrast, PMB did not affect ionomycin-induced increase in [Ca2+]i. These results strongly suggest that CA secretion induced by TPA or ionomycin is mediated via activation of protein kinase C. The results further indicate that in 56 mM K+- or ACh-evoked CA secretion, PMB inhibits the secretion by blocking Ca2+ influx into the cells.

Acetylcholine↗

PubMed1971