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Biomedical subjects

S Asaki

Publications and source records attributed to S Asaki.

At least 37 records · Page 2Linked to original sources
PubMed1995

Clinical evaluation of lansoprazole in the treatment of peptic ulcers: initial healing and prevention of relapse. Tohoku Peptic Ulcer Study Group.

The clinical usefulness of lansoprazole in the healing of gastric and duodenal ulcers, the S2-stage shift rate (white scarring rate), and endoscopic healing rate with respect to degree of gastric mucosal atrophy were investigated. The subjects were 50 gastric ulcer and 37 duodenal ulcer patients. The endoscopic healing rate in patients with gastric ulcers after initial treatment with lansoprazole was 92% after 8 weeks. The S2-shift rate was 38% after 8 weeks. The 8-week healing rate in patients without atrophy was 100% and with atrophy was 92%, although the difference was not statistically significant. The S2-shift rate in patients without atrophy was 42% and in patients with atrophy was slightly lower, at 37%, although the difference was not statistically significant. The endoscopic healing rate in patients with duodenal ulcers was 93% after 6 weeks, and the S2-shift rate was 59%. It is firmly established that atrophic gastric mucosa shows a reduction in mucosal defense factors. However, lansoprazole achieved good endoscopic healing rates and S2-shift rates even in patients with gastric ulcers with atrophic background mucosa.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1993

Double immunostaining for c-erbB-2 and p53 in human stomach cancer cells.

We examined 32 cases of surgically resected stomach cancer for the immunohistochemical expression of p53 and c-erB-2 protein and correlated the findings with clinical outcome and established prognostic factors. p53 Was observed in the nuclei of tumor cells in 11 of 32 cases (33%) and c-erbB-2 immunoreactivity was observed in nine of 32 cases (27%). In eight cases both p53 and c-erbB-2 were positive; however, double immunostaining revealed that less than a third of the same tumor cells were positive for both p53 and c-erbB-2 in these cases. The immunohistochemical localization patterns of p53 and c-erbB-2 were not related to the histopathologic differentiation of the carcinoma cells. No correlation was observed between expression of p53 and/or c-erbB-2 and the clinical outcome and established prognostic factors, including clinical stage and histologic types of the tumor examined. These results indicate that abnormalities of p53 and c-erbB-2 may not play major roles in the biologic behavior of human stomach cancer and that abnormalities in p53 and c-erbB-2 do not necessarily occur simultaneously in the development of stomach cancer.

Adenocarcinoma↗
PubMed1992

Effect of lansoprazole on intragastric pH. Comparison between morning and evening dosing.

Lansoprazole is a newly developed proton pump inhibitor. The purpose of this study was to determine whether morning or evening dosage gave better control of 24-hr intragastric pH. In this study, we examined the antisecretory effect of lansoprazole by repeated intragastric pH monitoring on four occasions in eight normal subjects and compared median 24-hr pH values and pH threshold time of pH greater than or equal to 4 between morning and evening dosing, following the administration of lansoprazole 30 mg once daily in either the morning or evening for seven days. Intragastric pH was monitored before and after seven days of treatment. Both morning and evening dosing caused a rise in the intragastric pH. Median pH for 24 hr was 4.3 and 1.6 with and without lansoprazole morning dosing and 4.6 and 2.1 for evening dosing, respectively. The pH threshold curve shifted to the right with lansoprazole treatment in either case. However, no differences were found between morning and evening dosing in terms of median 24-hr pH values or pH threshold time of pH greater than or equal to 4. These results indicate that lansoprazole can be given once daily in either the morning or evening because of its potent and long-lasting antisecretory activity.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1992

Effect of omeprazole on ascorbate free radical formation.

In order to study the effect of omeprazole on the K/[H+] value of ascorbic acid (K = the ascorbic acid-ascorbic free radical equilibrium constant), changes of the concentration of ascorbate free radical in guinea pig sera were examined after intraperitoneal administration of omeprazole. Furthermore, to see the in vitro effect of omeprazole on ascorbate free radical, changes were examined in ascorbate solutions after addition of omeprazole. It was found that the K/[H+] value in the serum increased significantly after administration of omeprazole and also that the drug amplified the electron spin resonance (ESR) signal intensity of ascorbate free radical in vitro. These results suggested that omeprazole acts like oxygen radicals.

Animals↗
PubMed1992

[Movement of gastric acid secretion and influence of proton pump inhibitors on histamine H2 receptor antagonist resistant ulcer].

Treatment of peptic ulcers has become easier with the advent of H2 blockers. However, H2 resistant ulcer still remain. These cases were screened by 24 hr-intragastric pH monitoring, which well reflects the status of gastric acid secretion. On the one hand, there were cases in which no nocturnal elevation in gastric pH was seen even after administration of H2 blocker (H2 blocker resistant ulcer). On the other hand, there were cases which were resistant to treatment with H2 blocker, although the gastric pH elevated. It is considered that omeprazole is effective for the former cases.

Adenosine Triphosphatases↗
PubMed1992

Predictors of relapse in peptic ulcer.

Four hundred and two patients with peptic ulcer were selected for acute therapy with either pirenzepine (100 mg/day) or cimetidine (800 mg/day) using the envelope method. Those who achieved healing within 3 months (251 patients) were randomized in a double-blind fashion to maintenance therapy with either pirenzepine (75 mg/day) or placebo. In a preliminary study of 163 patients in which a multiple regression life-table method was employed, 4 out of 15 possible predictors were found to have a significant influence on relapse. These were site of ulcer lesions, psychological stress, endoscopic findings at the time of healing of the original ulcers, and acute therapy. Stratified analysis of the evolution of relapse by the Cutler-Ederer life-table method indicated that several other factors also influenced relapse in certain patient subgroups. Most relapses (93.8%) occurred at the same site as, or close to the site of, the original ulcers, indicating that ulcer scars also play a role in relapse.

Adult↗
PubMed1991

[Salivary epidermal growth factor in patients with peptic ulcer].

Recent animal studies suggest salivary epidermal growth factor (EGF) has a cytoprotective effect in the upper GI tract and is one of the important factors to promote the healing of experimental ulcer. The present study was undertaken to clarify the role of salivary EGF in peptic ulcer patients. Saliva samples were collected from 129 endoscopically normal subjects and 232 peptic ulcer patients. Salivary EGF concentration was measured by RIA. Salivary EGF output in normal subjects was 5.26 +/- 0.26 (ng/5 min) (mean +/- SE). Those in patients with gastric ulcer (GU), duodenal ulcer (DU) and gastroduodenal ulcer (GDU) were 10.74 +/- 0.15, 8.13 +/- 0.83 and 9.79 +/- 0.91. EGF output in GU and GDU patients were higher than that in normal subjects respectively. Tractable GU patients (healed within 3 months with regular regimen) had higher EGF output than intractable GU patients. Among tractable GU patients, those who had healing within 8 weeks had higher output. EGF output in patients with recurrent GU was lower than that in non-recurrent GU patients. In 10 GU patients, EGF output became higher in healing stage than in active stage. Salivary EGF may promote the healing and prevent the recurrence of human gastric ulcer.

Adult↗
PubMed1991

[A cytoprotective role of extracellular superoxide dismutase in experimental stress ulcer models].

In an experimental stress ulcer models, we examined a pathophysiological role of EC-SOD in an extracellular fluid in guinea pig. Heparin has a releasing potency of EC-SOD into extracellular fluid from endothelial cell. In this study, we divided animals into four groups; 1) control animals, 2) animals injected with heparin (1,000 IU/kg), 3) animals injected with heparin and DDC (1 g/kg), 4) animals injected with DDC treatment. In these four groups, we measured ulcer index (UI) and lipid peroxides (LPO) of the gastric mucosa, before and serially after stress. Water-immersion, ethanol and burn were used as experimental stress. Animals injected with heparin inhibited the increase of UI and LPO of gastric mucosa induced by stress. This cytoprotective effect was abolished by DDC treatment. These results suggest that EC-SOD may be a cytoprotective factor in an extracellular fluid.

Animals↗
PubMed1990

Endoscopic treatment for submucosal tumors of the esophagus: studies in 25 patients.

Twenty-five patients with submucosal tumor of the esophagus were treated endoscopically. All patients underwent submucosography. The tumors were classified as intra-luminal or intra-mural types according to growth pattern. Twenty tumors were resected using electrocautery in single sessions. Another 5 lesions (more than 20 mm in diameter) were subjected to absolute ethanol injections in multiple sessions to necrotize the tissue, after the overlying mucosa was stripped off by electrocautery. These procedures were not accompanied with serious complications such as perforation or massive bleeding. Oozing bleeding occurred in 3 patients, which was easily stopped by topical injection of absolute ethanol with an endoscope. Esophageal stenosis did not occur. Local reccurence of a submucosal tumor was found in a patient after 14 months, and was retreated successfully. Although the wall of the esophagus is thinner than that of the stomach, endoscopic treatment for a submucosal tumor of the esophagus can be performed safely. Submucosography and endoscopic ultrasonography reveals the extent of the tumor in relation to the esophageal wall thickness. These examinations are helpful in preventing complications. Endoscopic treatment for submucosal tumors using electrocautery and topical injection of absolute ethanol were effective and safe.

Adult↗
PubMed1990

[Biological evaluation of extracellular superoxide dismutase observed in a state of acute gastric mucosal lesions].

In the experimental stress ulcer models of guinea pig superoxide dismutase-like plasma substance increased in plasma. Upon chromatography on heparin-Sepharose, this substance was separated into three fractions; A, without affinity for heparin; B, with intermediate affinity for heparin; C, with relatively strong heparin affinity, and the fraction C was specifically increased by a stress and a heparin injection. Analysis by a polyacrylamide gel electrophoresis (PAGE) of the fraction C revealed SOD activity, whose molecular weight was 135 K in a native state. The fraction C seemed to be the same as extracellular superoxide dismutase (EC-SOD) reported by Marklund. Assuming to the releasing potency of heparin, the major part of EC-SOD in the vasculature was most likely located on endothelial-cell surface. A pathophysiological role of EC-SOD released into plasma seemed to be an indicator of endothelial-cell damage by free radicals of endothelial cells and polymorphonuclear neutrophils (PMNs).

Acute Disease↗
PubMed1989

Biochemical examination on the increased superoxide dismutase-like plasma substance observed in a state of acute gastric mucosal lesions.

When experimental acute gastric mucosal lesions were produced in guinea pig by water-immersion and restraint stress, superoxide dismutase (SOD)-like substance in the plasma increased. On analysis by gel filtration, it was shown that the molecular weight of the increased SOD-like plasma substance was about 130,000, and even after treatment with trypsin, 84% of this substance remained. Since the molecular weight of intracellular SOD is about 40,000, it seems that this substance is similar to extracellular SOD, located on the endothelial cell-surface, as previously reported by Marklund et al. Our results suggest that in the presence of acute gastric mucosal lesions, SOD-like plasma substance is not identical to intracellular SOD, which derived from cell destruction by stress or free radical-induced microvascular damage or by hemolysis. Furthermore, this substance may itself work as a scavenger of free radicals generated under conditions, such as these described in the present experiment.

Animals↗
PubMed1989

Efficacy of absolute ethanol injection method for stress ulcer bleeding after major surgeries.

Emergency endoscopy, carried out in 342 cases of UGI overt bleeding at the Third Department of Internal Medicine, Tohoku University during the six year period from June 1979, demonstrated the necessity of endoscopic hemostasis in 171 cases (50%) with active bleeding, adhered fresh blood clot or exposed vessel with bloody gastric juice. The absolute ethanol injection method was applied to achieve hemostasis in all cases including 30 cases (18%) of postoperative stress ulcer bleeding after major surgeries. Temporary hemostasis was obtained successfully in all 30 cases and rebleeding did not develop. New bleedings in 2 cases (7%) were stopped by repeated injections of absolute ethanol. No patients died from bleeding nor underwent emergency or elective operation. Five patients (17%) died from complicated underlying diseases. Perforation developed in one case (3%). In this case new bleeding occurred on two occasions, and each time hemostasis was obtained. However, this patient showed early symptoms of perforation immediately before the third hemostasis, and was operated on after local injection of absolute ethanol. The complete hemostasis was achieved in 100% of postoperative stress ulcer cases by the ethanol method.

Adult↗
PubMed1989

Comparison of the efficacy of endoscopic ultrasonography and submucosography in diagnosing the depth of gastric cancer invasion.

Diagnosis of the depth of the cancer invasion is necessary to select the indication of endoscopic treatment. We used endoscopic ultrasonography (EUS) and Submucosography (SMG) to diagnose the depth of cancer invasion and compared their efficacy against 63 lesions in 60 cases of gastric and esophageal cancers. SMG could diagnose the invasion correctly in 97% of m (mucosa) cancers, 88% of sm (submucosa) cancers and 100% of advanced cancers. On the other hand, linear-type EUS could diagnose the cancer invasion correctly in 60% of the m cancers, 83% of the sm cancers and 100% of advanced cancers. The results of the comparison of radial-type EUS and SMG showed similar results. Both EUS and SMG are appropriate for the judgement of endoscopic treatments. However, for the selection of the indication of endoscopic treatment which is applied to relatively small sized lesions in general, SMG appears to be superior to EUS in both resolution power and accuracy in shooting.

Aged↗
PubMed1989

[Randomized-controlled study of treatment with UFT-MMC or UFT-ACR in advanced gastric cancer. Tohoku Study Group of Cancer Treatment for the Digestive Organs].

The effect of UFT-MMC- or UFT-ACR-therapy on the unresectable or recurrent gastric cancer was studied by a multicenter, randomized-controlled trial. All the patients who were randomly divided into the two groups were administered orally with 400 or 600 mg/day of UFT everyday. In addition, the UFT-MMC group was intravenously injected weekly for three weeks and then triweekly after six weeks with 6 or 8 mg/body of MMC, while the UFT-ACR group was intravenously injected with 20 mg/body of ACR for 5 serial-days every three weeks. Out of 88 cases registered, 75 (85.2%) were evaluable, consisting of 40 (31 complete cases) in UFT-MMC and 35 (27 complete cases) in UFT-ACR. There was no difference in various background factors between the two groups. PR, NC and PD was 10/31, 15/31 and 6/31 in the UFT-MMC group, whereas 0/27, 22/27 and 5/27 in the UFT-ACR group, respectively. The efficacy in the former group was higher, though not significant (U-test, p = 0.052), than that in the latter group. However, there was no difference in the 50% survival time (4.9 months in UFT-MMC vs. 5.4 months in UFT-ACR) of the either group.

Aclarubicin↗
PubMed1989

[Campylobacter pylori and diseases of the stomach].

In spite of extensive clinical studies the pathogenicity of Campylobacter pylori in various diseases of the stomach is still not fully elucidated. In peptic ulcer Campylobacter pylori has not provided a reasonable explanation for the localized and solitary development of ulcer lesion which is one of characteristic features of this clinical entity. Our previous clinical study revealed that relapse occurs mostly at or near the scar of the preceding ulcer lesion and occurs more often in red scar than in white scar in peptic ulcer. Therefore, the scar was chosen to investigate whether there is a correlation between Campylobacter pylori and relapse. Twenty patients with healed gastric ulcer were biopsied in duplicate at 4 different sites, namely at the center of and near the scar of the preceding ulcer lesion, in the body and pyloric antrum. One of the duplicate specimen was stained, and the other cultured. Number of the colony observed on the plate was highest at the scar center followed by near the scar or in the body, and the pyloric antrum showed the lowest. Campylobacter pylori was detected in 46.7% of red scar, and 20% of white scar. Campylobacter pylori may play a pathogenic role in some patients of peptic ulcer, but not in all. Namely Campylobacter pylori is one of factors which may cause in imbalance between offensive and defensive powers at gastric mucosa and may lead to development of ulcer lesion. In case of positive bacteriological test, therefore, as to presence of Campylobacter pylori, the preventive measure for relapse such as bismuth preparation may be considered.

Adult↗