Search PubMed⌕ Search

Biomedical subjects

Y Otani

Publications and source records attributed to Y Otani.

At least 91 records · Page 5Linked to original sources
PubMed1998

Hemostatic capability of rapidly curable glues from gelatin, poly(L-glutamic acid), and carbodiimide.

The hemostatic capability of rapidly curable glues composed of gelatin and poly(L-glutamic acid) (PLGA) was compared with that of the conventional fibrin glue. The hydrogels produced from mixed gelatin and PLGA aqueous solution within several seconds by addition of water-soluble carbodiimide (WSC) was applied to the dog spleen injured by needle pricking. The WSC-catalyzed gelatin-PLGA glues exhibited higher hemostatic capability than the fibrin glue. The total amount of bleeding from the injured spleen until hemostasis when the gelatin-PLGA hydrogel glues were applied was significantly smaller than that of the fibrin glue application. The gelatin-PLGA glue application enhanced the success rate of complete hemostasis to a significantly greater extent than the fibrin glue, while the frequency of glue applications until achieving complete hemostasis decreased. The gelatin PLGA hydrogels strongly adhered to the surface of dog spleen, whereas the fibrin hydrogel was easily detached from the spleen surface. It was concluded that this strong adhesion mechanically suppressed the bleeding, leading to enhanced hemostasis by the rapidly curable gelatin-PLGA glues.

Animals↗
PubMed1998

Effect of additives on gelation and tissue adhesion of gelatin-poly(L-glutamic acid) mixture.

Gelation and tissue adhesion of mixtures of gelatin and poly (L-glutamic acid) (PLGA) aqueous solution were investigated in the presence of additives following the addition of a water-soluble carbodiimide (WSC) that induced chemical cross linking between gelatin and PLGA. To prevent spontaneous gelation of the mixed solution through physical cross linking between gelatin molecules at room temperature, additives were added to the mixed solution. Among the additives studied, starch and urea were effective in preventing the spontaneous physical gelation. The mixed gelatin and PLGA solution set to a cross-linked hydrogel within scores of second by WSC addition, irrespective of the presence of urea, whereas the viscosity of the solution with added starch was too high to measure the gelation time. The cross-linked gelatin-PLGA hydrogels with and without urea showed higher bonding strength to soft tissues than fibrin glue. This was in marked contrast to gelatin-PLGA hydrogels with soluble starch. Irrespective of the presence of urea, the gelatin-PLGA hydrogels gradually biodegraded in the back subcutis of mice over 3 months and no severe inflammatory response to the hydrogels was observed. These findings indicate that urea is promising as an additive to prevent spontaneous physical gelation of the mixed gelatin and PLGA aqueous solution without changing the characteristics of WSC-induced cross linking and tissue adhesion of the formed hydrogel.

Animals↗
PubMed1998

Lymph node metastasis of early gastric cancer with submucosal invasion.

BACKGROUND: A clinicopathological study of early gastric cancer with submucosal invasion was carried out in relation to lymph node metastasis. METHODS: A retrospective study was conducted of 245 patients with submucosal gastric cancer treated by gastrectomy combined with D2 lymph node resection between 1985 and 1994 in a university hospital. RESULTS: Lymph node metastasis was observed in 34 patients (14 per cent). The mortality rate due to recurrence in patients with lymph node metastasis (three of 34) was significantly higher than in those without lymph node metastasis (five (2 per cent) of 211) (chi2 = 3.95, 1 d.f., P < 0.05). Tumour size, depth of invasion, lymphatic involvement of cancer cells and preoperative diagnosis of advanced cancer correlated significantly with the presence of lymph node metastasis. When the submucosal carcinomas were classified into three categories according to depth of invasion by dividing the submucosal (sm) layer into three equal parts, sm1, sm2 and sm3, the incidence of lymph node metastasis increased from 2 per cent to 12 and 20 per cent respectively. CONCLUSION: When the pathological report reveals sm1 invasion after laparoscopic or endoscopic surgery, reoperation should not be necessary because sm1-carcinomas with diameters of less than 2 cm do not usually metastasize to the lymph nodes.

Adult↗
PubMed1998

A protease inhibitor attenuates gastric erosions and microcirculatory disturbance in the early period after thermal injury in rats.

The effects of camostat mesilate, a synthetic serine protease inhibitor on gastric microcirculation and active oxygen species generated by leucocytes from the gastric and jugular veins in the early period after thermal injury were assessed. Male Wistar rats were anaesthetized and a 30% full skin-thickness dorsal burn was inflicted. Camostat mesilate (100 mg/kg) was dissolved in distilled water and administered orally to rats 40 min before thermal injury (the camostat group). The control animals (the vehicle group) were administered distilled water orally. Rolling leucocytes as well as Monastral blue B deposits in venules were observed using in vivo microscopy. Active oxygen species were measured by chemiluminescence. Camostat mesilate decreased the total length of gastric erosion, venular deposits of Monastral blue B, and rolling of leucocytes in venules, and relatively increased luminol-dependent chemiluminescence activity generated by zymosan-stimulated leucocytes 15 min after thermal injury. These results suggest that serine proteases are involved in the formation of gastric erosions and gastric microcirculatory disturbance in the early period after thermal injury.

Animals↗
PubMed1998

Trends of average intake of macronutrients in 47 prefectures of Japan from 1975 to 1994--possible factors that may bias the trend data.

To describe the geographical patterns and trends of macronutrient intake in Japan for the recent 20 years, we analyzed the data sets of the National Nutrition Surveys (J-NNS). First, we calculated regression coefficients for survey year by prefecture for energy, protein, fat, and carbohydrate intake. These results, however, could be affected by the changes in age and sex distributions of the survey samples. Secondly, as the food consumption data were based on household as a unit, we used proportions of the subjects who belong to age-specific groups and female subjects in a sub-sample for each prefecture in a given year for adjustment by general lineal model. As a result, 1% increase in the subjects aged 1-4, 10-19 and 65- years and female subjects was equivalent to the changes in average energy intake by -5.88, +2.27, -1.45 and -1.62 kcal, respectively. After the adjustment for age and sex, number of significant negative coefficients among 47 prefectures decreased for energy and carbohydrate intake, and that of positive coefficients increased for fat intake. This suggested that unadjusted trend data might lead to an overestimation of decreasing trends of energy and carbohydrate intake, and an underestimation of increasing trend of fat intake in the recent 20 years.

Adolescent↗
PubMed1998

[Limited operation for lung cancer: wedge resection using stapling device].

We employed wedge resection using stapling device for peripheral, clinical stage I lung carcinoma in selected poor-risk patients. Out of 10 patients, four developed local recurrence and one had the second primary in the same lobe resected. Compared with patients having lobectomy with 91% of a recurrence free rate in three years, those who underwent wedge resection had the lower rate of 53%. We conclude that wedge resection using stapling device cannot be an acceptable procedure even for poor-risk patients.

Adenocarcinoma↗
PubMed1998

[Laparoscopic surgery for early gastric cancer--its advantages and pitfalls].

We have successfully established two different laparoscopic procedures for early gastric cancer since March 1992, which are laparoscopic wedge resection of the stomach using a lesion-lifting method and laparoscopic intragastric mucosal resection. The indication is as follows; (A) mucosal cancer, (B) < 25 mm, if the lesion is elevated type, (C) < 15 mm and Ul (-), if the lesion is depressive type. The advantages of these methods are; 1) minimally invasiveness, 2) sufficient surgical margin, 3) feasibility of detailed histology, 4) feasivility of perigastric lymph node dissection. In contrast, there are several problems to be solved, which are; 1) preoperative diagnostic accuracy of the depth of cancer invasion, 2) possibility of reoperation because of sm invasion or lymphatic or venous invasion in final histology, 3) possibility of postoperative stenosis after laparoscopic intragastric mucosal resection for the lesion near the cardia, 4) incidence of metachronous multiple gastric cancer. In conclusion, if the indication is properly selected, these laparoscopic procedures are curative and minimally invasive treatment for early gastric cancer.

Gastric Mucosa↗
PubMed1998

[Recent progress of matrix metalloproteinase (MMP) research and its clinical application for cancer therapy].

The matrix metalloproteinases (MMPs) are a family of secreted and membrane-bound zinc-endopeptidases. These enzymes are capable of degrading the extracellular matrix, including collagens, laminin, proteoglycan and fibronectin. In some human cancers, a positive correlation has been demonstrated between MMP expression and the likelihood of developing metastasis. An imbalance between MMPs and the tissues inhibitor of metalloproteinases (TIMPs) may play a significant role in the invasive phenotype of cancers. Although TIMPs have been shown to inhibit tumor metastasis in some in vivo models, they are not suitable for pharmacologic applications due to their short half-life in vivo and large molecular size. In this paper, recent advances in MMP research and reports of clinical applications of synthetic MMP inhibitors for cancer patients are reviewed.

Humans↗
PubMed1998

Rebamipide attenuates gastric microcirculatory disturbances in the early period after thermal injury in rats.

In our previous study we showed that rebamipide attenuated gastric erosions and active oxygen species released only from the gastric mucosa and not from circulating leukocytes after thermal injury. This study was designed to examine whether rebamipide affects the potential of active oxygen generation from circulating leukocytes, and attenuates microcirculatory disturbance caused by thermal injury to skin. Rats were anesthetized and a 30% full skin-thickness dorsal burn was inflicted. Microvascular images and leukocytes were observed using in vivo microscopy. Endothelial damage was assessed by monastral blue B deposits. Active oxygen species were measured by the chemiluminescence method. Rebamipide (100 mg/kg) decreased leukocyte rolling and monastral blue B deposits in venules but did not improve arteriolar contractions 15 min after thermal injury. These results suggest that rebamipide preserves gastric microcirculation possibly through inhibition of leukocyte adhesion and endothelial damage caused by thermal injury to skin.

Alanine↗
PubMed1998

Characteristics of Helicobacter pylori strains isolated from patients with different gastric diseases.

The pathogenesis of chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis is considered to be related to infection by Helicobacter pylori. The purpose of this study was to investigate the characteristics of H. pylori strains isolated from patients with various gastric diseases. Fifty strains of H. pylori were clinically isolated at Keio University Hospital and were assessed for (i) vacuolating cytotoxin (VT) production, by cytotoxic assay using rabbit kidney (RK) 13 cells; (ii) the expression of cytotoxin associated gene (cagA), by polymerase chain reaction; and (iii) motility on a semi-solid plate. Positivity for VT production by H. pylori strains isolated from patients with chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis, was 100%, 89%, 92%, 100%, and 60%, respectively. There was no significant difference in the incidence of positivity for cagA among the strains isolated from different gastric diseases. Swarming distances, which indicate motility of H. pylori strains, were 12.7, 13.2, 12.8, 16.6 and 9.2mm in strains from chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis, respectively, with H. pylori isolated from remnant gastritis showing significantly less motility than H. pylori isolates from other diseases. There were no significant differences in VT production and cagA positivity among the H. pylori strains.

Animals↗
PubMed1998

[A clinical study on the cases of ischemic colitis: comparison of clinical images based on time from onset of the disease to detection of bloody stool].

A study was performed on 28 cases of ischemic colitis. The patients were divided into three groups: Group A (9 cases with bloody stool detected within 2 hours after the onset of abdominal pain), Group B (7 cases with bloody stool detected in 2 to 6 hours), and Group C (12 cases with bloody stool detected after more than 6 hours). These cases were comparatively studied. Variables used were as follows: (1) age, (2) sex, (3) constipation, (4) vomiting, (5) peak value of WBC count (/microliter) after admission, (6) peak value of log CRP (microgram/dl), (7) presence of ulcerative lesion in endoscopic findings in acute stage. Using Group A B and C as classification variables, canonical discriminant analysis was performed. As a result, clear linearity was recognized in Group A-->B-->C, and the values (5), (6) and (7) were extracted as the corresponding variables. For these variables, significant difference was also noted in multivariate analysis of covariance. These results suggest that it is possible to predict the severity of the disease to some extent as represented by objective markers of inflammation by finding the time from onset of abdominal pain to detection of bloody stool.

Adolescent↗
PubMed1997

The role of stromal cells in the expression of interstitial collagenase (matrix metalloproteinase-1) in the invasion of gastric cancer.

BACKGROUND AND OBJECTIVES: In one of the steps of tumor invasion and metastasis, tumor cells must invade surrounding tissues and degrade the components of the basement membranes. Interstitial collagenase (matrix metalloproteinase-1: MMP-1) has been also investigated in relation to cancer invasion and metastasis. METHODS: We investigated the formation and mechanism of MMP-1 expression using gastric cancer cell lines and gastric fibroblasts derived from normal gastric mucosa by ELISA and immunohistochemistry. RESULTS: Production of MMP-1 protein in gastric fibroblasts was stimulated significantly by adding the conditioned medium of MKN-74. Localization of MMP-1 protein in the xenografted gastric cancer cell lines was heterogeneous according to different cell lines. CONCLUSIONS: These results suggested that the production of MMP-1 protein in tumor invasion was regulated by interaction between stromal cells, particularly fibroblasts, and tumor cells.

Animals↗
PubMed1997

Difference in gene expression for matrix metalloproteinase-1 between early and advanced hepatocellular carcinomas.

The histological observation that well-differentiated cancer cells in early hepatocellular carcinoma (HCC) invade portal tracts and/or fibrous bands and that these fibrous tissues then disappear suggests the participation of matrix metalloproteinase-1 (MMP-1) in the degradation of fibrous tissue. To confirm this hypothesis, the authors investigated the localization of both the MMP-1 protein and its messenger RNA (mRNA) in early HCC immunohistochemically and by in situ hybridization using complementary DNA (cDNA) and synthetic antisense probe of MMP-1; they then compared the results with those in advanced HCC. MMP-1 gene transcripts and protein were observed in well-differentiated cancer cells of early HCC but not in moderately or poorly differentiated cancer cells. Thus, cancer cells producing MMP-1 in early HCC may destroy the portal tract tissue adjacent to the cancer lesion and/or the fibrous band of cirrhosis. These results seem to have demonstrated a difference in the mechanism of cancer growth and invasion between early and advanced HCCs.

Adult↗
PubMed1997

Benign tumors of the lung: a 20-year surgical experience.

In the following report, we describe our investigation of the diagnosis and operative methods for benign tumors of the lung, in which the surgical treatment was selected due to suspicious malignancy. This study included 22 patients with benign tumors. The patients' mean age was 55 years old. The histological diagnosis was made postoperatively prior to 1985 and intraoperatively after 1986. Hamartoma was the most common of the benign tumors. In benign tumors, the preoperative diagnosis was almost the same as the postoperative one. Of the patients with benign tumors, 78% underwent lobectomy or segmentectomy prior to 1985, and none have undergone any invasive procedures since 1986. Malignant tumors are sometimes difficult to distinguish from benign tumors preoperatively. Therefore, intraoperative histological examinations are necessary in cases in which malignancy is suspected. In such cases, a smaller invasive procedure should be selected due to the possibility of the tumor being benign.

Adult↗
PubMed1997

Left ventricular fibroma in an aged patient: report of a case.

We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery.

Aged↗