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K Tazawa

Publications and source records attributed to K Tazawa.

At least 37 records · Page 2Linked to original sources
PubMed1998

Effect of prolonged staining with hematoxylin on detecting Helicobacter pylori in hematoxylin-eosin-stained gastric mucosa.

Helicobacter pylori (H. pylori) is identifiable in hematoxylin-eosin (HE)-stained preparations, particularly under a prolonged hematoxylin staining condition. The staining intensity of H. pylori bodies was increased when the hematoxylin staining period was doubled from 5 min, the routine period of Meyer's hematoxylin staining, to 10 min. The staining intensity of the background epithelial nuclei was only mildly increased. Hematoxylin-eosin staining employing a prolonged hematoxylin staining period gave detectability of H. pylori comparable to May-Giemsa and immunoperoxidase staining. The modified HE method is thus very useful and practical for identifying H. pylori in routine gastric biopsy specimens.

Adult↗
PubMed1998

Microdialysis assessment of 5-fluorouracil release from thermosensitive magnetoliposomes induced by an electromagnetic field in tumor-bearing mice.

The current study was designed to evaluate the properties of thermosensitive magnetoliposomes (TMs), a new drug carrier proposed by the authors, in an electromagnetic field pertaining to their selective heating and drug release under an in vivo condition. TMs containing 5-fluorouracil (5-FU) were prepared by reverse-phase evaporation, injected into the tumor mass of B 16-BL6 melanoma in mice, and selectively heated by a 500-kHz electromagnetic field. The release profile of 5-FU from TMs was examined by using a microdialysis technique. The temperature of TMs in the tumor was effectively elevated to 42 degrees C and maintained at this temperature, overcoming the "cooling effect" of blood flow and surrounding tissues. The release kinetics of 5-FU from TMs was successfully analyzed by physiological modeling, which allows the prediction of intratumor drug concentrations during electromagnetic field exposure under various conditions. In conclusion, this study first demonstrated an in vivo evidence for the electromagnetic field-induced thermosensitive release of a drug from TMs in a tumor with the use of microdialysis.

Animals↗
PubMed1998

[The TNM classification of cancer--from the viewpoint of pathology].

The 5th international TNM classification (proposed in 1997) is an anatomical classification of cancers used all over the world. In Japan, various kinds of Japanese classification of cancers have widely been accepted since 1962. Researchers may be confounded at international cancer conferences because of some differences in these classification. We here summarize the history and criteria of the present TNM classification and describe the concept of new N factors additional and in the 5th edition. In the Japanese versions of cancer classification, the concepts of H and P factors should be reconsidered. The importance of the cytologic diagnosis in ascites is discussed and pathological grades of differentiation into the new cancer staging are introduced.

Humans↗
PubMed1997

Glomerular proliferating cell kinetics in acute post-streptococcal glomerulonephritis (APSGN).

To investigate the time sequence of glomerular cell proliferation in acute human glomerulonephritis, renal biopsy tissues were examined from 15 acute post-streptococcal glomerulonephritis (APSGN) patients (who were biopsied 1-31 days after onset), using an immunoperoxidase technique with monoclonal antibodies against proliferating cell nuclear antigen (PCNA) and various cell surface markers. Few, if any, PCNA+ cells were observed in normal glomeruli, but many cells were positive for PCNA in the acute phase of APSGN. Glomerular PCNA+ cells were observed either within glomerular tufts, or lining Bowman's capsule (parietal epithelial cells); the number of positive cells tended to decrease exponentially as the disease duration increased (r = -0.91, P < 0.0001). PCNA+ cells within glomerular tufts were further identified by double immunostaining. PCNA was not found in PMN or T cells, but a small proportion of macrophages were PCNA+. Most of the remaining PCNA+ cells were resident glomerular cells; the proportion of PCNA+ endothelial cells (CD31+) was over 80 per cent in the early phase, but as the disease continued the proportion of mesangial cells (alpha-smooth muscle actin+) increased to about half of the total PCNA+ cells within the tuft. These data indicate that the hypercellular glomeruli in APSGN are due not only to immune cell infiltration, but also to resident glomerular cell proliferation, probably induced by locally produced growth factors.

Acute Disease↗
PubMed1997

Surgical stress inhibits the growth of fibroblasts through the elevation of plasma catecholamine and cortisol concentrations.

To investigate the influence of surgical stress on fibroblast proliferation, serum samples were collected from 12 patients within 1 week after they had undergone gastrointestinal surgery, and the effect of these samples on the growth of fibroblasts from neonatal mice were evaluated by an in vitro assay. In addition, the course of the postoperative plasma levels of the stress-induced hormones, adrenaline, noradrenaline, and cortisol, and the direct effects of these substances on the proliferation of fibroblasts, were also analyzed. The sera collected from patients on the 1st, 3rd, and 7th postoperative day had a significant antiproliferative effect on the growth of fibroblasts. The evaluation of the levels of plasma catecholamines (adrenaline and noradrenaline) and cortisol revealed elevated postoperative concentrations of these substances in three patients, and the peaks were seen on the 1st or 3rd postoperative day. Furthermore, the growth of cultured fibroblasts was inhibited when each of these substances was added to the medium at a concentration comparable to the level found in the postoperative sera. These results suggest that adrenaline, noradrenaline, and cortisol may thus be among the circulating fibroblast growth inhibitors in postoperative patients and that surgical stress affects the formation of granulation in an inhibitory manner through the elevation of these stress-induced substances.

Animals↗
PubMed1997

Primary leiomyosarcoma arising in the lesser sac: report of a case.

We describe herein a very rare case of leiomyosarcoma arising in the lesser sac. A 58-year-old man with a psychiatric disorder was admitted to our department for the investigation of epigastralgia and nausea which he had been suffering since the previous month. A laparotomy revealed that the abdominal mass, found on physical examination, was a primary lesser omental tumor, histological examinations of which confirmed a diagnosis of leiomyosarcoma. The tumor cells showed a DNA diploid pattern. Leiomyosarcoma of the lesser sac is extremely unusual and it is important that it be distinguished from an extraluminal tumor of the abdomen.

DNA, Neoplasm↗
PubMed1997

Hepatocellular carcinoma presenting as extrahepatic mass on computed tomography.

The authors describe an extremely rare case of extrahepatic hepatocellular carcinoma. The patient was a 70-year-old man who was examined by a local doctor because of abdominal discomfort. Barium meal examination demonstrated a defect occupying the lesser curvature of the stomach from the middle of the corpus to the fornix. On an abdominal computed tomography (CT) scan, the lesion, 10 cm in diameter, touched the lower surface of the caudate lobe of the liver. Under laparotomy, the tumor was found between the caudate lobe of the liver and posterior wall of the gastric corpus. As the tumor appeared to be connected with the caudate lobe by a pedicle, only the tumor was resected. Histological examination showed the tumor to be hepatocellular carcinoma of Edmondson's grade III-IV, pedunculated type.

Aged↗
PubMed1997

Inhibitory effects of fluorinated pyrimidines, 5'-DFUR, UFT and T-506, in a model of hepatic metastasis of mouse colon 26 adenocarcinoma-assessment of inhibitory activity and adverse reactions at the maximum tolerated dose.

The effects of fluorinated pyrimidines, 5'-DFUR, UFT and T-506, on a mouse model of hepatic metastasis were assessed in regard to inhibitory activity and adverse reactions at the maximum tolerated dose. The model was prepared by injecting the mouse colonic cancer cell line, colon 26, into the portal vein of CDF1 mice. At the treatment regimens employed for 5'-DFUR (1.0 mmol/kg/day, p.o., daily from days 1 to 7), UFT (0.1 mmol/kg/day, p.o., daily from days 1 to 7), and T-506 (0.074 mmol/kg/day, i.v., days 1, 4, 7, and 10), complete inhibition of hepatic metastasis was obtained in six out of seven mice (85.7%) with 5'-DFUR, and in five out of six mice (83.3%) with T-506. Significant inhibition of hepatic metastasis was not achieved with UFT (3/7, 42.9%). 5'-DFUR and T-506 showed the highest rate of inhibition of hepatic metastasis, suggesting that these drugs would be effective for the prophylactic treatment of metastatic disease. 5'-DFUR and UFT exhibited mild adverse reactions such as loss of body weight.

Adenocarcinoma↗
PubMed1997

Experimental acute glomerulonephritis induced in the rabbit with a specific streptococcal antigen.

FITC-labelled IgG obtained from patients convalescing from acute poststreptococcal glomerulonephritis (APSGN) stains glomeruli of patients with early APSGN. We previously reported a streptococcal antigen (preabsorbing antigen (PA-Ag)) that preabsorbed the stain out of sera from the convalescent patients and thus prevented glomerular staining. To confirm the nephritogenicity of PA-Ag, we administered up to 40 mg of this antigen to rabbits for 8 days and observed them for up to 9 weeks. Immunohistological analysis showed diffuse and global glomerular staining for C3 without notable staining for gamma-globulin. Light microscopic examinations revealed slight to moderate proliferative glomerulonephritis with exudative change. Control rabbits, which received similar doses of bovine serum albumin, did not show significant staining for C3. A transient and significant decrease in CH50 was observed from weeks 3 to 7 (9.7 +/- 0.3 U/ml at week 3; normal range 12.9 +/- 0.6 U/ml). This experimental model showed a resemblance to immunological and immunohistological features of APSGN in humans. Although the precise mechanisms are yet to be determined, complement activation by PA-Ag seems to hold a key position in this model and in the human disease.

Acute Disease↗
PubMed1997

Ileocolon interposition as a substitute stomach after total or proximal gastrectomy.

OBJECTIVE: The authors evaluated ileocolon interposition as a substitute stomach after total gastrectomy (TG) or proximal gastrectomy (PG). SUMMARY BACKGROUND DATA: Although the jejunum frequently is used for reconstruction to create a substitute stomach after TG or PG, there are few reports on ileocolon interposition. METHODS: The authors performed ileocolon interposition in 47 patients who underwent TG (N = 18) or PG (N = 29) for malignant gastric lesion and evaluated the function of this structure as a substitute stomach using esophagoscopy, manometry, pH-metry, emptying time, oral glucose tolerance test (OGTT), and postoperative body weight changes. RESULTS: No patient reported any reflux symptoms or showed endoscopic findings of reflux esophagitis. These results were well supported by manometry and acid loading pH-metry. Emptying time and OGTT showed good capacity as a reservoir of food, and the postoperative body weight averaged more than 90% of preoperative weight. Clinically, no significant difference between these two groups was recognized during long-term follow-up for up to 12 years after operation. There were no cases of direct operative death, and the 5- and 10-year survival rates were 64.7% and 40.2%, respectively. CONCLUSIONS: Ileocolon interposition after TG or PG has the advantages of preventing postoperative reflux esophagitis and of providing functional replacement of the stomach as a reservoir for ingested food.

Adult↗
PubMed1997

Characterization of a liver metastatic variant of murine colon 26 carcinoma cells.

Intraportal vein injection of highly metastatic L5 cells consistently resulted in liver metastases (increases in the number of tumor colonies in the liver), whereas inoculation of P cells rarely did. L5 cells invaded the basement membrane Matrigel in greater numbers than did P cells, suggesting that the metastatic potential of L5 cells is partly related to enhanced invasive properties. The enhanced adhesion of L5 cells to fibronectin-, laminin- and Matrigel-coated substrates, as well as their haptotactic migration to fribronectin, may be associated with the preferential expression of VLA-2 and VLA-4 integrins on the surface of these cells detected by flow cytometry. Gelatin zymograms showed that the degradative activity of 72-kD gelatinases was greater in L5 cells than P cells. These results indicate that, in addition to adhesiveness and motility, the invasive ability of L5 cells may also be attributed to enhanced gelatinolytic activity. L5 cells grew more rapidly than P cells in vitro. Thus, an experimental model using highly metastatic colon 26 L5 cells would be useful for analyzing the molecular mechanism of liver metastasis and for evaluating the efficacy of treatment of occult micrometastases which may already have been disseminated at the time of surgery.

Adenocarcinoma↗
PubMed1997

Clinical results of treatment of advanced esophageal carcinoma with hyperthermia in combination with chemoradiotherapy.

Chemoradiotherapy combined with hyperthermia was administered to 35 patients with advanced esophageal carcinoma who either required preoperative treatment or had nonresectable disease. As a rule, each patient received a total dose of 30 Gy in 15 daily fractions of 2 Gy, 5 d/wk. Bleomycin or cisplatin, in combination with fluorouracil, was employed as chemotherapy. Hyperthermia was applied by intraluminal heating twice a week for a total of six sessions using an apparatus (IH-500T; Japan Crescent Co Ltd; Tokyo, Japan) (radiofrequency, 13.56 MHz) with an intraesophageal applicator and two extracorporeal applicators placed on the chest and back. This treatment method obtained a response rate of 80%, consisting of a complete response rate of 22.9% and partial response of 57.1%. In 15 cases, the tumor became resectable (resectability rate, 42.9%) following treatment. The histologic study of the resected specimens revealed absence of viable tumor cells in five patients (33.3% of the resected cases) (markedly effective), and in six patients (40.0%), the combined therapy was considered to be moderately effective. No complications considered due to hyperthermia itself were recognized. The overall 5-year survival rate was 11.8%. In conclusion, chemoradiotherapy combined with hyperthermia was locally effective, yielding an overall response of 80.0%. However, the prognosis of the patients remains unfavorable. Advanced esophageal carcinoma requires treatment taking into account lymphatic and hematogenic metastasis at the beginning of treatment.

Aged↗
PubMed1997

Anticarcinogenic action of apple pectin on fecal enzyme activities and mucosal or portal prostaglandin E2 levels in experimental rat colon carcinogenesis.

Pectin is a partially methoxylated polymer of galacturonic acid obtained from fruits. Among pectin, apple pectin exerts stronger bacteriostatical action on Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeruginosa and Escherichia coli in comparison with citrus pectin. In this study, we used water-soluble methoxylated pectin from apple. The diet, supplemented by 20% apple pectin, significantly decreased the number of tumors and the incidence of colon tumor. PGE2 level in distal colonic mucosa in 20% apple pectin fed rats were lower than those in basal diet fed rats. Fecal beta-glucuronidase activities in the apple pectin fed group, which has been considered a key enzyme for the final activation of Dimethylhydrazine metabolism to carcinogens in the colonic lumen, were signifieantly lower than those in control group at initiation stage of carcinogenesis. In the case the concentrations of beta-glueosidase and azoreductase were also decreased. The effect of apple pectin on the colon carcinogenesis may partially depend on PGE, concentration decrease in colonic mucosa and on the type of pectin, also related to fecal enzyme activities.

Animals↗
PubMed1997

[Effects of OK-432 intraportal administration on cell-mediated immune responses].

The effects of OK-432 and/or MMC on host immunity were studied in patients with advanced colorectal cancer. OK-432 was administered to the portal vein, and MMC was dispersed into the peritoneal cavity for prevention of liver metastasis. In the MMC group, NK activity was significantly reduced at 7 days postoperatively, while such a reduction was not seen in the OK and OK + MMC groups. The administration of OK-432 decreased the postoperative proportion of suppressor T cells in the lymphocyte subsets more than that of MMC group. Our results strongly suggest that intraoperative administration of BRM to the patients with advanced colorectal cancer can significantly prevent postoperative immunosuppression.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

[Circadian chemotherapy in cancer patients].

Continuous infusion of 5-FU at night was performed for four patients: three had liver metastasis (one with gastric cancer and two with rectal cancer) and one had local recurrence of rectal cancer. The chemotherapy schedule was 400 mg/m2/day 5-FU intraarterial or intravenous infusion from 6:00 p.m. to 6:00 a.m. for five days repeated every 3 weeks. There were one complete response, two partial responses and one with no change. It is expected that the chemotherapy of 5-FU at night will result in a high efficacy and lower toxicity.

Adult↗
PubMed1996

Prolapse of the small intestine through a ruptured vagina caused during sexual intercourse: report of a case.

We report herein the rare case of a 56-year-old woman who suffered vaginal rupture into the peritoneal cavity during sexual intercourse, through which the small intestine prolapsed out from the vaginal opening. The patient had undergone abdominal hysterectomy 4 years earlier. An emergency laparotomy was performed which revealed rupture in the posterior fornix of the vagina and peritonium through which prolapse of the small intestine had occurred. The prolapsed intestine was pulled back into the pelvic cavity, and the vagina and peritonium were repaired. Macroscopically, the operative findings revealed no inflammatory changes or evidence of malignancy in the abdominal cavity. Thus, although rare, a ruptured vagina caused by sexual intercourse should also be considered in the field of surgery, even when a middle-aged woman presents with acute abdominal symptoms without a history of any other traumatic episode.

Coitus↗
PubMed1996

Strangulation ileus resulting from encasement of a loop of the small intestine by the great omentum, caused by abnormal adhesion.

We treated a patient with a mechanical ileus resulting from encasement of a loop of the small intestine by the great omentum, caused by abnormal adhesion. Apart from its occurrence postoperatively with laparotomy, strangulation of small intestine into the omentum is very rare, and its occurrence without underlying disease, except in children, has not been documented previously.

Aged↗