Biomedical subjects

Y Tabuchi

Publications and source records attributed to Y Tabuchi.

At least 55 records · Page 3Linked to original sources

PubMed1996

[A reused suction catheter was broken and produced a tracheobronchial foreign body].

We present a rare case involving a broken suction catheter that became lodged in the tracheobronchial tree. An eight-month-old infant was scheduled for hernioplasty. Following intubation with a 4 French (Fr.) endotracheal tube, a 5 Fr. reused suction catheter was applied for suctioning a moderate amount of secretion. This catheter had been resterilized by ethylene oxide gas (EOG). Insertion of the catheter into the tube was not done smoothly, and we could not obtain any secretion. During the extraction of the suction catheter by force, the catheter broke. The distal fragment (20 cm length) seemed to have been lodged in the tracheobronchial tree. Prior to its removal by bronchoscopy, the endotracheal tube was extubated. Fortunately the remaining part of the catheter come out with the tube. Ten cm of the fractured catheter was included in the tube and 5 cm protruded from the tube. The catheter of smaller diameter is easy to be broken even by weaker force. After resterilization by EOG for once, there was no change in length and force at breaking point. Elongation of the broken catheter (85.5%) was less compared with the new sample (155%). At the breaking point, half of the cross section was very smooth and looked as if it had been cut by a razor, while the other half appeared to have been broken by pulling. The break may have started from the crack which had occurred at the insertion or resterilization. Therefore, we should restrict the reuse of small suction catheters, and should always utilize the catheter of the largest size possible.

Anesthesia, Inhalation↗

PubMed1995

Ca(2+)-activated outward-rectifier K+ channels and histamine release by rat gastric enterochromaffin-like cells.

Gastric enterochromaffin-like (ECL) cells were isolated from rat gastric fundic mucosa by Percoll density-gradient centrifugation and counter-flow elutriation. About 67% of cells in the purified cell suspension were ECL cells, which were reacted with anti-histidine decarboxylase antibody. A23187, a calcium ionophore, at 0.1-10 microM induced histamine release from ECL cell-rich suspension, indicating that the Ca2+ pathway is involved in the mechanism of histamine release from the ECL cells. A23187 at 5 microM significantly increased outward-rectifier cationic current in 62% of cells in the ECL cell-rich factions. A23187-sensitive cells showed acridine orange uptake. In single-channel recordings, a Ca(2+)-dependent outward-rectifier K+ channel of large conductance (146 +/- 22 picosiemens) was found in the cell that showed acridine orange uptake. The channel opened in a voltage-dependent manner at 0.1 microM of intracellular free Ca2+ concentration. These results may suggest that opening of the Ca(2+)-activated K+ channel is one of the steps involved in the mechanism of histamine release in ECL cells.

Animals↗

PubMed1995

Protective effect of DS-4574, a peptidoleukotriene receptor antagonist, against endotoxin-induced intestinal injury in rats.

We evaluated the protective effect of DS-4574 (6-(2-cyclohexylethyl)-[1,3,4]thiadiazolo[3,2-a]-1,2,3- triazolo[4,5-d]pyrimidin-9(3H)-one), a peptidoleukotriene receptor antagonist, against intestinal mucosal injury evoked by endotoxin in rats by exploring changes in hematocrit and plasma leakage along with morphological features. Treatment with Escherichia coli endotoxin (5 mg/kg i.v.) alone elicited hemoconcentration, vasocongestion and a marked mucosal necrosis. DS-4574 (10-50 mg/kg) effectively prevented these changes on either oral or intraduodenal administration. These results demonstrate that peptidoleukotrienes may be key mediators in the intestinal injury induced by endotoxin in rats.

Animals↗

PubMed1995

Ebselen, a seleno-organic compound, protects against ethanol-induced murine gastric mucosal injury in both in vivo and in vitro systems.

The inhibitory effect of the seleno-organic compound ebselen on ethanol-induced murine gastric mucosal injury was examined. In an in vivo study, absolute ethanol (50 microliters/mouse, oral) produced marked gastric mucosal necrosis along with hemorrhage or edema and elevations in both lipid peroxide and peptidoleukotriene levels in the fundic mucosa. Pretreatment with ebselen (30 and 100 mg/kg, oral) significantly prevented this gastric mucosal injury and, further, remarkably decreased the elevated lipid peroxide and peptidoleukotriene levels. In an in vitro study using a murine gastric surface mucous cell line GSM06, exposure to ethanol concentration dependently elicited cell damage (7.5-17.5% ethanol) and an increase in lipid peroxides without alterations in peptidoleukotrienes (15% ethanol). Addition of ebselen (10 and 100 microM) to this system (15% ethanol) significantly inhibited the cell damage and completely prevented the increase in lipid peroxide level. These results indicate that ebselen protects against murine gastric mucosal injury both in vivo and in vitro, and that this protection may be related at least in part to its inhibitory action on lipid peroxides.

Animals↗

PubMed1995

Analysis of proliferative activity using antiproliferating cell nuclear antigen antibody in colorectal cancer.

Using anti-PCNA antibody (PC10), an immunohistochemical study of the expression of PCNA in formalin-fixed and paraffin-embedded materials of colorectal cancer patients was performed and correlation of PCNA expression with clinicopathological findings and DNA ploidy pattern was studied. PCNA labeling rate (PCNA LR) was estimated in the advancing margin of the tumor and ranged from 23.8% to 77.9%. There was a significant difference in lymphatic vessel invasion, liver metastasis and Dukes' stage between the groups with high (> 48.7) and low (< 48.7) PCNA LR (P < 0.05). No differences were seen in tumor size, histological type, lymph node metastasis or DNA ploidy pattern. In patients with younger age, infiltration to neighboring organs, a high degree of venous invasion, and peritoneal dissemination, the frequency of high PCNA LR tended to be higher (P < 0.1). The results above suggest that a high proliferative activity as defined by evaluation of the PCNA LR at the advancing margin of the tumor may be one of the parameters of malignant potential and helpful as a predictor of liver metastasis in colorectal cancer.

Antibodies, Monoclonal↗

PubMed1995

Variant type of teratoma appearing as a primary solid dermoid tumor in the rectum: report of a case.

We report herein the rare case of a 39-year-old woman found to have a primary solid dermoid tumor in the rectum. The patient presented after noticing a small amount of anal bleeding, and physical examination revealed a walnut-sized hard tumor, palpable in the anterior rectum, located about 9 cm from the anal verge. Morphologic examinations revealed a polypoid lesion with some hair surrounded by rectal mucosa, and four biopsy specimens from the lesion showed normal squamous epithelium. The tumor, which measured 2.5 x 2.1 x 1.3 cm, was removed by endoscopic polypectomy. Microscopically, the tumor was diagnosed as a solid dermoid tumor without a cyst, a variant type of mature teratoma or dermoid cyst. Since 1914, only 12 such cases, including ours, have been reported in Japan. The clinical features and diagnostic and therapeutic methods applied thereto are discussed.

Adult↗

PubMed1995

[Effects of 2-(3,4-dimethoxyphenyl)ethylamine derivative (ecabapide, DQ-2511) and its metabolites on water-immersion restraint stress-induced gastric ulcers in rats].

Ecabapide (DQ-2511) has been demonstrated to be effective in preventing water-immersion restraint stress ulceration of rats. In the present study, we aimed to define the active molecular features of ecabapide. Seven of 9 degraded materials identified as ecabapide metabolites were synthesized and their antiulcer activities were compared with that of the parent compound. Ecabapide was potent to prevent gastric ulcer formation at the doses of 30-300 mg/kg i.p. Three metabolites (V, VIII and IX) were also active to inhibit ulceration induced by the stress. The antiulcer activity of IX was similar to that of ecabapide, whereas V and VIII had less activities. After the oral administration of ecabapide, the plasma levels of IX reached to less than 15% of that of ecabapide and also IX was largely excreted into the feces. Therefore, the potential implication of the metabolite (IX) as the active component in the antiulcer effect of ecabapide could be excluded. Furthermore, it is also unlikely that the high polar metabolites (IV and VII) are implicated in significant contribution for antiulcer action. In conclusion, we have shown that ecabapide prevents water-immersion restraint stress-induced gastric ulcers, and that this activity is probably mediated by the action of the parent compound.

Animals↗

PubMed1995

[Perioperative management of dialysed patients for orthopedic surgery].

Recently, renal osteodystrophy is a remarkable problem in patients on long-term hemodialysis (HD). In this retrospective study, we evaluated the perioperative management of 21 patients receiving orthopedic surgery between January 1990 and December 1992. These patients had been maintained on HD for an average of 8.6 years (range, 18 months-20 years). The primary causes of orthopedic surgery were amyloidosis, diabetic gangrene, rheumatoid arthritis and fractures. Laminectomy, replacement of arthropathy, osteosynthesis and amputation of the lower extremity were undertaken. General anesthesia was performed on six patients. Vecuronium was given to all of these patients. Isoflurane was used in 5 patients and sevoflurane in 1 patient. Regional anesthesia was used in 15 patients. During anesthesia, the average infusion rate of intravenous fluids was 2.7 ml.kg-1.h-1, and the intraoperative complications included hypertension in 16, hypotension in 12, arrhythmia in 4 and prolonged sedation in 2 patients. Postoperative complications included hyperkalemia in 2, pneumonia in 2, psychological disorder in 3, clotting fistula in 1 and delayed wound healing in 7 patients. One early death in a diabetic patient following amputation occurred on the 13th postoperative day. Preoperative HD was performed within 24 hours and postoperative HD within 72 hours of the operation. Nafamostat mesilate was used as an anticoagulant. Excessive removal of potassium must be avoided during preoperative HD to prevent arrhythmia. The well-managed elective patients gave a good result. However, extreme care in nutrition and infection control should be taken, especially in diabetic patients.

Anesthesia↗

PubMed1995

[Minimizing of the blood preparation for elective surgery by maximum surgical blood order schedule as well as type and screen--two year's experience in Nagahama City Hospital].

To make the most of the blood products, we have introduced maximum surgical blood order schedule (MSBOS) as well as Type and Screen (T&S) into Nagahama City Hospital. As the hospital dose not have blood transfusion service unit, we, anesthesiologists set up MSBOS and the procedure of blood preparations for elective surgery. The results of two year's experience demonstrate that there was no trouble by reducing the blood preparation. The cross-match to transfusion ratio (C/T ratio) in surgical procedures and that of red cell products in our hospital have decreased, the effective use of red cell products has been promoted, and the outdating of the blood product has been reduced.

Blood Loss, Surgical↗

PubMed1994

Inhibitory effect of DS-4574, a mast cell stabilizer with peptidoleukotriene receptor antagonism, on gastric acid secretion in rats.

We examined the inhibitory effect of DS-4574 (6-(2-cyclohexylethyl)[1,3,4]thiadiazolo[3,2-alpha]-1,2,3- triazolo[4,5-d] pyrimidin-9(3H)-one), a mast cell stabilizer with peptidoleukotriene receptor antagonism, on gastric acid secretion stimulated by several secretagogues in rats. In anesthetized rats with acute gastric fistulas, DS-4574 (50 mg/kg, intraduodenal) significantly inhibited gastric acid secretion induced by both carbachol (50 micrograms/kg, s.c.) and pentagastrin (75 micrograms/kg, s.c.) but not by histamine (2.5 mg/kg, s.c.). In unanesthetized pylorus-ligated rats, DS-4574 (10 and 25 mg/kg, intraduodenal) markedly suppressed increases in gastric acid output and histamine leakage into the gastric juice produced by carbachol (0.1 mg/kg, s.c.) or pentagastrin (1 mg/kg, s.c.). When the relationship between acid output and histamine leakage elicited by carbachol and pentagastrin was assessed, there was a close correlation (r = 0.84) that was highly significant (P < 0.01). In the in vitro study with rat gastric tissues, DS-4574 (10(-7)-10(-5) M) had no effect on the K(+)-dependent ATPase activity or on aminopyrine uptake into mucosal preparations containing parietal cells stimulated by carbachol (10(-5) M), histamine (10(-4) M), or dibutyryl-cyclic AMP (10(-3) M). These results suggest that the effect of DS-4574 may be mediated by inhibition of endogenous histamine from histamine-storing cells in the stomach.

Animals↗

PubMed1994

Antisecretory effect of DS-4574, a mast cell stabilizer with peptidoleukotriene antagonism, on gastric acid secretion in the pig.

The antisecretory effect of DS-4574, a mast cell stabilizer with peptidoleukotriene antagonism, on the hypersecretion of gastric acid stimulated by several secretagogues was examined in the pig. Goettingen miniature pigs with chronic gastric fistula were used. Intramuscular injection of carbachol (60 micrograms/kg), tetragastrin (50 micrograms/kg) or histamine (200 micrograms/kg)-induced gastric acid hypersecretion. Intraduodenal administration of DS-4574 (10 and 20 mg/kg) significantly inhibited both the hypersecretion induced by carbachol and that by tetragastrin. On the other hand, DS-4574 (50 mg/kg, intraduodenal) did not suppress histamine-induced hypersecretion. In the in vitro study, no effect on hog gastric K(+)-dependent ATPase activity was found at concentrations of DS-4574 from 10(-7) to 10(-4) M. These results were highly similar to those in the rat. The suppression of histamine release from histamine-containing cells in the gastric mucosa of the rat was concluded to be an antisecretory effect of DS-4574.

Adenosine Triphosphatases↗

PubMed1994

Inhibitory effect of DS-4574, a peptidoleukotriene antagonist with mast cell stabilizing action, on compound 48/80-induced gastric mucosal lesions in rats.

We evaluated the inhibitory effect of DS-4574, a peptidoleukotriene antagonist with mast cell stabilizing action, on rat gastric mucosal lesions induced by compound 48/80 (C48/80: a mast cell degranulator), in comparison with those of disodium cromoglycate (DSCG: a mast cell stabilizer), LY171883 (a peptidoleukotriene antagonist) and cimetidine (a histamine H2 receptor antagonist). Subcutaneous administration of C48/80 (1 mg/kg) once daily for four consecutive days produced extensive gastric lesions in the fundic mucosa. DS-4574 (20, 50 and 100 mg/kg/day, oral) and DSCG (200 mg/kg/day, intraperitoneal) treatment markedly inhibited formation of these mucosal lesions, but LY171883 (100 and 200 mg/kg/day, oral) and cimetidine (400 mg/kg/day, oral) treatment did not. Moreover, DS-4574 and DSCG significantly suppressed both hyperhistaminemia and histamine release from rat peritoneal mast cells induced by C48/80. These results indicate that the inhibitory effect of DS-4574 on gastric lesions induced by C48/80 may be related to its mast cell stabilizing action, but to neither its antisecretory nor its peptidoleukotriene antagonistic activity.

Acetophenones↗

PubMed1994

Mechanism of the inhibition of hog gastric H+,K(+)-ATPase by the seleno-organic compound ebselen.

The effect of 2-phenyl-1,2-benzisoselenazol-3 (2H)-one (ebselen, CAS 60940-34-3), a seleno-organic compound, on the partial reaction steps of H+,K(+)-ATPase in hog leaky gastric vesicles was examined. Ebselen inhibited K(+)-dependent ATPase activity (IC50 = 0.06 mumol/l), phosphoenzyme formation (IC50 = 0.25 mumol/l), and K(+)-dependent p-nitrophenylphosphatase activity (IC50 = 0.09 mumol/l: dephosphorylation step of this enzyme). Furthermore, this compound prevented changes in the fluorescence intensity of flourescein isothiocyanate-labeled enzyme (E1-->E2K form, IC50 = 0.33 mumol/l). Pretreatment with 2 mmol/l of dithiothreitol (DTT) used as a sulfhydryl compound completely protected against these inhibitory effects. These findings indicate that ebselen-induced inactivation of gastric H+,K(+)-ATPase may result from prevention of the partial reaction steps, which include phosphorylation, dephosphorylation and conformational change (E1-->E2K form), through interference with sulfhydryl groups of the enzyme.

4-Nitrophenylphosphatase↗

PubMed1993

Protective effect of DS-4574 on gastric mucosal injury induced by acidified ethanol in rats.

We compared the protective effect of DS-4574, a peptidoleukotriene receptor antagonist with mast cell stabilizing action, on rat gastric mucosal injury induced by acidified ethanol to that of LY171883, a selective peptidoleukotriene receptor antagonist. Oral treatment with DS-4574 (1-10 mg/kg) or LY171883 (100 and 300 mg/kg) markedly suppressed this mucosal necrosis. Moreover, DS-4574 (10 mg/kg) significantly inhibited both mucosal edema and degranulation of mucosal mast cells. LY171883 (300 mg/kg) protected only from mucosal edema, but not degranulation of mucosal mast cells. These results suggest that DS-4574 possesses protective actions against gastric injury including the reduction of degranulation of mucosal mast cells, which are different from those of LY171883.

Acetophenones↗

PubMed1993

Establishment of gastric surface mucous cell lines from transgenic mice harboring temperature-sensitive simian virus 40 large T-antigen gene.

We succeeded in establishing two gastric surface mucous cell lines (designated as GSM06 and GSM10), which produce periodic acid-Schiff (PAS)- and concanavalin A (Con A)-positive glycoproteins, from a primary culture of gastric fundic mucosal cells of adult transgenic mice harboring a temperature-sensitive simian virus 40 large T-antigen gene. At the permissive temperature (33 degrees C), GSM06 and GSM10 cells grew until confluent monolayers were formed and have now been in culture for more than 9 months with regular passaging. Con A-horseradish peroxidase- and PAS-positive staining indicated that these cells retain the characteristics of gastric surface mucous cells. GSM06 cells showed temperature-sensitive growth in culture and expressed SV40 large T-antigen at the permissive temperature but not at a nonpermissive temperature (39 degrees C). In contrast, GSM10 cells showed temperature-insensitive growth and expressed T-antigen at both permissive and nonpermissive temperatures. To our knowledge, this is the first report of the establishment of gastric surface mucous cell lines from animals. These immortalized cell lines with normal characteristics may serve as good experimental models for the basic and applied biology of gastric surface mucous cells.

Animals↗

PubMed1993

Suppressive effect of doxorubicin on liver recurrence after resection of colonic VX2 cancer lesions: difference in efficacy according to the injection protocol.

An animal model with liver cancer recurrence was induced by resecting colonic VX2 cancer lesions in 57 rabbits, and the effects of doxorubicin (ADR) on the recurrence were examined. Animals were divided into a control group and three chemotherapeutic groups: a portal injection group, to which ADR was injected into the portal vein after resection of the primary lesions; a peripheral injection group, to which ADR was injected into a peripheral vein after resection; and a preoperative injection group, to which an ADR dose of 0.5 mg/kg was peripherally injected 0, 1, and 2 days prior to resection followed by a portal injection of ADR 0.5 mg/kg after resection. The rate of liver recurrence was 100% in the control group, whereas it was 0% and 60% in the portal ADR 1.0 and 0.5 mg/kg injection groups, and 60% and 100% in the peripheral ADR 1.0 and 0.5 mg/kg injection groups. In the preoperative group, the rate was 0%, 100%, and 67% in the animals injected 2, 1, and 0 days prior to resection, respectively. These results suggest that portal injection or appropriate combinations of preoperative peripheral and portal injections of ADR are more effective than peripheral or portal injection alone in the suppression of liver recurrence.

Animals↗

PubMed1993

Antisecretory and antiulcer effects of ebselen, a seleno-organic compound, in rats.

The effects of ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-on), a metal-containing organic compound, on gastric secretion and gastric ulceration were examined in rats. Intraduodenal ebselen (30 to 300 mg/kg) significantly and dose-dependently inhibited gastric secretion in pylorus-ligated rats. Both aspirin- and water-immersion restraint stress-induced ulcers were significantly prevented by oral administration of ebselen at doses equivalent to the antisecretory doses. These results indicate that the antisecretory effect of ebselen underlies its antiulcer effect in these models.

Animals↗

PubMed1993

[Prophylactic effects of mitomycin C (MMC) on the liver recurrence in a rabbit gastric VX2 cancer model with high frequency of the recurrence].

Prophylactic effects of mitomycin C (MMC) injection protocol with different dose, periods and routes on liver recurrence were examined, using 53 gastric VX2 cancer rabbits. All the gastric cancer lesions without liver metastases were resected 14 days after implantation of VX2 cancer cells into the stomach, and all the animals were autopsied 14 days after resection. Multiple liver recurrence was found in 75% of MMC non-injection control 8 rabbits. The recurrence was not found in 10 animals with portal MMC 0.5 and 0.25mg/kg injection after resection, although 80% of 5 animals with the 0.125mg/kg injection after resection revealed the recurrence. The recurrence was not found in 4 animals with peripheral MMC 1.0mg/kg injection, but found in 60% of 5 animals with the MMC 0.5mg/kg injection after resection. In the animals with peripheral MMC 0.25mg/kg injection 2, 1 and 0 days before resection and with portal MMC 0.125mg/mg injection after resection, the recurrence was found in 83, 60 and 80% of 6, 5 and 5 respective animals. These results suggest that prophylactic injection of MMC for liver recurrence is more effective in portal than peripheral injection, but that the preoperative and peripheral injection has no efficacy.

Animals↗