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Publications (10)24.47 Total impact

  • Article: Radiation and surgical stress induce a significant impairment in cellular immunity in patients with esophageal cancer
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    ABSTRACT: The effects of preoperative radiation plus surgical stress on immunity were examined in 29 patients with esophageal cancer, including 14 patients who experienced radiation therapy and 15 who did not, as well as 15 age-, sex- and body weight-matched control subjects. Absolute numbers of the total lymphocytes and OKT3 (all T cells), OKT4 (helper/inducer T cells) and OKT8 (suppressor/cytotoxic T cells) positive lymphocytes were almost the same in both patient groups before treatment. Both thein vitro response to phytohemagglutinin (PHA) and antibody dependent cell-mediated cytotoxicity (ADCC) were depressed in the patients when compared to the controls before treatment. Dual treatment of radiation and surgery led to a marked reduction of lymphocytes in the numbers and activities of PHA and ADCC, when compared to findings in the non-radiation group. Especially, the number of OKT4 positive lymphocytes and the OKT4 to OKT8 ratio decreased most and recovery was slow. While ADCC activity in the non-radiation group recovered at 28 postoperative days (POD), the response to PHA did not return to the pretreatment levels. Serum levels of IgG, IgM and IgA were within normal limits throughout the course of treatment. The B1 (all B cells) positive lymphocytes significantly decreased after the treatments. These results suggest that radiation plus surgery shifts the host immunity toward immunosuppression and induces a significant impairment of cellular immunity in patients with esophageal cancer.
    Surgery Today 08/1989; 19(5):535-543. · 1.22 Impact Factor
  • Article: Decreased interleukin generation in patients with cancer of the digestive system. A correlation between interleukin 1 and interleukin 2 production
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    ABSTRACT: The generating capacity of interleukin 1 (IL-1) and interleukin 2 (IL-2) by peripheral blood mononuclear cells (PBMNC) was measured in 40 patients with digestive cancer (20 localized and 20 disseminated) and 20 age- and sex-matched control subjects. The localized carcinoma patients showed normal IL-1 production and a significantly depressed IL-2 production (p<0.05) when compared to the healthy individuals. The disseminated carcinoma patients exhibited a significant impairment of both IL-1 and IL-2 production in comparison with the healthy controls (IL-1: p<0.001, IL-2: p<0.001) and the localized carcinoma patients (IL-1: p<0.001, IL-2: p<0.001). A significant correlation was observed between IL-1 and IL-2 generation in all the cancer patients (r=0.458, p<0.01). These results suggest that progressive tumor growth may result in decreased interleukin production by the host PBMNC, and that related mechanisms, which are more susceptable to lymphocytes than monocytes, may be involved in the impairment of both IL-1 and IL-2 production.
    Surgery Today 04/1988; 18(5):527-532. · 1.22 Impact Factor
  • Article: Reduction of estrogen and prolactin receptors in 7,12-dimethylbenz(a)anthracene-induced rat mammary tumor by high doses of estrogen
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    ABSTRACT: Daily injections of 100 μg17 β-estradiol, or 250 μg tamoxifen, for 10 days led to a regression of the 7,12-dimenthylbenz(a)anthracene (DMBA)-induced rat mammary tumor. Estrogen receptor (ER), progesterone receptor (PgR), and prolactin receptor (PRL-R) in the regressed tumor were significantly reduced in the estrogen-treated rats. ER and PRL-R were low but PgR increased significantly in the tumor of the tamoxifen-treated rats. A single administration of 100 μg estradiol induced a transient decrease of ER and PRL-R, and an increase of PgR, in the DMBA-tumor. Similar decreases in ER and PRL-R and the increase of PgR were observed 8 hours after the 5th injection of 100 μg estradiol—a time when the tumor had already regressed. These results suggest that high dose-estrogen has a direct inhibitory effect on the concentration of both ER and PRL-R in the DMBA-tumor, and that this effect might be accumulative with repeated administrations. It is unlikely that the inhibition of the estrogenic effect caused by loss of ER is the sole mechanism of the regression of the DMBA-tumor, since the increased synthesis of PgR as a marker of estrogen action was observed even after the ER-reduction and tumor-regression.
    Surgery Today 04/1987; 17(5):395-401. · 1.22 Impact Factor
  • Article: Mechanisms of acute gastric mucosal lesion accompanying obstructive jaundice
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    ABSTRACT: The mechanism of acute gastric mucosal lesion (AGML) accompanying obstructive jaundice was studied in male Wistar rats, with special reference to the effect of bile acids in plasma on mucosubstances in the gastric mucosa. Following Iigation of the common bile duct, total plasma level of bile acids increased 24 folds over the control level, and gastric mucosal mucus contents, measured biochemically or histochemically, significantly decreased. Effect of increased bile acids in the blood stream on the gastric mucosa was estimated by continuous intravenous administration of sodium taurocholate. After 24 hours infusion, both gastric acid output and gastric mucus contents significantly decreased. Further imposition of restraint and water immersion stress produced AGML significantly earlier than in control rats with continuous intravenous infusion of 0.9% NaCl. These data suggest that the increased plasma level of bile acids play an important role on the reduction of the gastric-mucosal defense mechanism in obstructive jaundice directly through their toxic effects, and that this easily results in the formation of AGML under additional stresses.
    Journal of Gastroenterology 04/1986; 21(1):6-16. · 4.16 Impact Factor
  • Article: Studies of the mechanisms of gastric bleeding under obstructive jaundice
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    ABSTRACT: Mechanisms of gastric bleeding under obstructive jaundice were studied in adult male Wistar rats. Following ligation of the common bile duct, mucosal noradrenaline significantly decreased in both the pyloric and fundic gland areas of the gastric mucosa by 20 days after the operation. Serotonin increased only in the pyloric gland area, and histamine increased in the fundic gland area. Urinary excretion of free noradrenaline significantly increased after the ligation. Three weeks after the ligation, restraint and water immersion experiments were conducted. Under water immersion, gastric blood flow significantly reduced in rats with obstructive jaundice compared to controls. Acid output decreased in both groups. Gastric bleeding was noted in the fundic gland area significantly earlier in the ligated rats than in the non-ligated rats. Administration of noradrenaline s.c. 30 minutes before immersion significantly blocked the reduction in gastric blood flow and protected the gastric mucosa against acute bleeding under immersion. These results suggested that prolonged obstructive jaundice may deplete noradrenaline in the gastric mucosa, and that gastric mucosal ischemia caused by this sympathetic dysfunction plays an important role in the formation of acute gastric bleeding under obstructive jaundice.
    Journal of Gastroenterology 04/1983; 18(2):71-78. · 4.16 Impact Factor
  • Article: Studies on alkaline phosphatase isoenzyme in gastric carcinoma tissues
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    ABSTRACT: An analysis of the alkaline phosphatase (ALP) isoenzyme in 75 gastric carcinoma tissues was performed. The properties and the originating cells of ALP isoenzymes in them were clarified by using both enzyme histochemical and biochemical methods which had respective superiorities. Also the relationship between intestinal metaplasia and gastric carcinoma was discussed. Liver, placental and small intestinal type ALPs were found in the carcinoma tissues. No ALP activity was found in carcinoma cells except in the stromal cells in 46 out of 75 cases. In all of these cases, only liver type ALP was found. While, in 29 cases, the activity was also found in carcinoma cells. In these cases, placental and small intestinal type ALPs were found in addition to liver type ALP in 26 and 3 cases, respectively. These results indicated that liver type ALP came from the stromal cells and placental and small intestinal type ALPs came from carcinoma cells The ALP found in carcinoma cells was placental (Nagao isoenzyme) type in most cases. While, the ALP in intestinal metaplastic epithelial cells was small intestinal type in all cases. No sufficient evidence indicating the relationship between intestinal metaplasia and gastric carcinoma was obtained in respect of ALP isoenzyme.
    Journal of Gastroenterology 04/1981; 16(2):110-121. · 4.16 Impact Factor
  • Article: Validity of long-term recordings of electrical activity of the stomach by chronically implanted monopolar suction electrodes in the conscious dog
    Yasunori Atobe, Masanobu Akagi, Katsuhide Nishi
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    ABSTRACT: Twenty-four-hour changes in gastric electrical activity were recorded in conscious dogs by means of chronically implanted monopolar suction electrodes. The electrical activity consisted of an initial potential followed by a second potential with various amplitude and duration depending upon the time after feeding. Amplitude of the second potential was well correlated to magnitude of each contraction. Characteristics of the electrical activity were qualitatively similar to those obtained with the intracellular microelectrode technique. 24-hour changes in cycles of electrical activity were divided into four phases; the first phase (lasting for 2–4 hours after feeding) characterized by a significant decrease in the cycle, the second phase (until 6–8 hours after feeding) in which the cycle gradually increased, the third phase (10–16 hours after feeding), and the last phase (lasting to the next meal), showing a marked variation in the cycle. These changes occurred irrespectively at the time of feeding and were consistent day after day as long as the animals were held on a constant feeding schedule. The recording method was suitable for recording gastric electrical activity which would provide more precise informations occurring in the intracellular electrical activity of the stomach in a long period of time under a physiological condition.
    Journal of Gastroenterology 09/1980; 15(5):452-463. · 4.16 Impact Factor
  • Article: Histochemical observations of polyglucose synthesized by enzyme activities in human gastric carcinoma
    Masanobu Maeno, Koichi Takagi, Masanobu Akagi
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    ABSTRACT: Polyglucose particles histochemically synthesized from glucose 1-phosphate by phosphorylase and branching glycosyltransferase were observed in the gastric carcinoma cells, in intestinal metaplastic epithelium of the gastric mucosa and in fetal epithelium of the fetal gastric mucosa by light and electron microscopical studies. Light microscopical observations resembled those in previous reports. As for the electron microscopical observations, in gastric carcinoma cells, the polyglucose synthesizing area were expansively widened by a deposition of synthesized polyglucose particles. Three patterns of their intracellular distribution, (Focal type, scattered type and singly deposited type) were observed. Besides, two types of polyglucose particle were synthesized. One type appeared as monoparticles which were relatively similar in size and the other type appeared as rosette-like structures which varied in size. Larger polyglucose particles which resembled the polyglucose particle synthesized in the fetal epithelium were observed among them. In the intestinal metaplastic epithelium, polyglucose particles which were similar in size were synthesized in narrow focal areas of the cytoplasmic matrix. The distribution, shape and size of polyglucose particles synthesized in the carcinoma cells were irregular as compared with those in the intestinal metaplastic epithelium. It seems that these irregularities were due to the influence of enzyme deviation caused by carcinoma.
    Journal of Gastroenterology 07/1980; 15(4):311-323. · 4.16 Impact Factor
  • Article: Partial purification and characterization of CA19-9 antigen from the ascitic fluid of a patient with pancreatic cancer
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    ABSTRACT: CA19-9 immunoreactive protein was partially purified from the ascitic fluid of a patient with pancreatic cancer by perchloric acid fractionation, gel chromatography and Affi-gel Blue column chromatography, resulting in a purified sample of 5.0 × 106 CA19-9 units per milligram of protein (3700-fold purification). Western blotting analysis of this purified sample revealed a single band of molecular weight 210 kDa. Although the original ascitic fluid showed a high CA125 immunoreactivity, this purified sample had no CA125 immunoreactivity. The elution pattern for CA19-9 activity on Affi-gel Blue column is quite distinct from that for CA125. These results suggest that CA19-9 antigen in carcinoma patients may be identical or very similar to that recently purified from the culture media of the colorectal cell line SW1116 and is distinct from CA125 antigen.
    Clinical Biochemistry.
  • Article: Gastric cancer diagnosed by biopsy of the uterine cervix
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    ABSTRACT: Biopsy of the uterine cervix from a 46-year-old woman who suffered from epigastric pain and weight loss showed metastatic adenocarcinoma. The primary site of the tumor was the stomach. At laparotomy, disseminated adenocarcinoma on the peritoneum and Krukenberg's tumor in the right ovary were found. A palliative partial gastrectomy, resection of the right ovary, and postoperative chemotherapy were performed. The possible mechanism of metastasis of extragenital cancer to the uterus is discussed.
    Gynecologic Oncology.