Biomedical subjects

S Koga

Publications and source records attributed to S Koga.

At least 235 records · Page 13Linked to original sources

PubMed1988

Prophylactic therapy for peritoneal recurrence of gastric cancer by continuous hyperthermic peritoneal perfusion with mitomycin C.

Continuous hyperthermic peritoneal perfusion (CHPP) with a solution that contains mitomycin C (CHPP-M) has been clinically introduced as a prophylactic treatment for peritoneal recurrence of gastric cancer with serosal invasion. Two studies, each with a treated and a control group, were performed. In the historical control study the postoperative 3-year survival rate of patients (73.7%) in the treated group (n = 38) was significantly higher than the survival rate (52.7%) of those in the control group (n = 55) (P less than 0.04). In the random control study the survival rate (83%) of patients in the treated group (n = 26) was also higher than that (67.3%) of those in the control group (n = 21) in the 30 months that followed gastric surgery. However, there was no significant difference. In the historical control study with respect to the postoperative complications, anastomotic leak was observed in 8.5% of patients who were given CHPP-M and 12.8% patients who did not have CHPP-M. In the random control study anastomotic leak was observed in 3.1% of patients who had CHPP-M and 7.1% of patients who did not have CHPP-M. The incidence of adhesive ileus in patients having CHPP-M did not increase in historical or random control groups. Postoperative prolonged intestinal paresis or chemical peritonitis were not induced by CHPP-M. These results indicate that CHPP-M is a simple, safe, and readily available prophylactic therapy for peritoneal recurrence that may follow gastric cancer surgery.

Adult↗

PubMed1988

Carcinogenic potential of the noncancerous epithelium in patients with oesophageal cancer.

Detailed histopathological examination of serial blocks and subserial sections of the entire resected oesophagus in 63 patients operated upon for oesophageal cancer revealed 11 associated minute superficial cancers, independent and apart from the main tumours, in 10 patients (15.9 per cent). Only one of these eleven lesions was diagnosed preoperatively, and only three of the eleven lesions were detected macroscopically on the resected specimens. The high incidence of such coexisting independent lesions may indicate a possible increased multicentric carcinogenic potential in the non-cancerous epithelium of patients who have had an antecedent oesophageal cancer. These results emphasize the need for careful attention to the choice of margins during surgical resection of the oesophagus.

Aged↗

PubMed1988

Clinicopathologic study of esophageal cancer associated with simultaneous metastatic lesions in the stomach.

Between 1965 and 1985, 89 Japanese patients with esophageal squamous cell carcinoma underwent esophagectomy. In five of them (5.6%), a simultaneous metastatic lesion from the esophageal cancer was detected within the stomach in the resected specimens. Preoperative diagnosis of the gastric lesions had been made in none of the five patients because of an obstruction that was due to esophageal cancer. All gastric lesions were located at the gastric cardia, close to the esophagocardial junction, with a mean distance of 6.9 +/- 2.0 cm from the primary esophageal lesions. Provision of a gastric tube that contains metastatic lesions, for reconstruction of a new alimentary tract after esophagectomy, must be avoided. In cases of inadequate preoperative gastric examination, gastric lesions should be searched for intraoperatively, not only by serosal inspection and palpation, but also by mucosal inspection and palpation after partial proximal gastrectomy.

Carcinoma, Squamous Cell↗

PubMed1988

BCG induced killer cell activity.

To investigate the mechanism of Bacillus de Calmette Guérin (BCG) bladder instillation therapy, the killer cell activity induced in peripheral blood mononuclear cells (PBMNCs) after BCG instillation was examined. Significant cytotoxic activity against natural killer (NK) cell resistant target tumor cells was detected after 3 days of instillation. To characterize this BCG induced cytotoxic activity further, human PBMNCs were cultured with BCG in vitro. From 24 h maximum cytotoxicity was obtained and continued for 3 days, then decreased slightly. Neither a DNA synthesis inhibitor Cytosine-arabinoside (Ara-C) nor a cytotoxic T cell (CTL) generation inhibitor Cyclosporine A inhibited this killer cell activation. Monoclonal antibody treatment revealed that both precursor and effector cells are Leu1-, 3a-, 7+, 11b+. The recognition specificity from cold target competition experiments was selective. Taken together NK type precursor was activated with BCG into NK type effector which has wider spectrum of target cells than usual NK cell.

Cyclosporins↗

PubMed1988

Serum zinc and copper changes after gastrectomy in aged patients with gastric cancer.

Serum zinc and copper levels were evaluated in patients with gastric cancer who had undergone gastrectomy. These patients were divided into two age categories; namely, the aged group, comprising 39 patients over the age of 70 years, and the younger group, comprising 23 patients younger than 50 years. The data before and after surgery were compared between the two groups. Serum zinc levels in the aged group were significantly lower than those in the younger group, both before and after surgery. Serum copper levels, however, did not differ significantly between the two groups. The serum Cu/Zn ratio was also analyzed according to the histological stages of cancer (stages I to IV), and compared between the two age-classified groups. The aged group showed a higher Cu/Zn ratio at all stages, whereas in the younger group, the ratio was significantly higher at stage IV than in the earlier stages. Preoperative serum zinc, copper, and the Cu/Zn ratio were studied in relation to the complication of anastomotic leak after surgery. The Cu/Zn ratio in the aged patients with this complication was significantly higher than that in the aged patients without it. These results suggest that the Cu/Zn ratio may be an important factor in determining nutritional parameters in the aged.

Adult↗

PubMed1988

Experimental studies of the effects of local hyperthermia on blood flow, oxygen pressure and pH in tumors.

The heat-induced environmental changes in tumor tissues are considered to influence the antitumor effect of hyperthermia or hyperthermochemotherapy, which is believed to complement the direct lethal effect of heat on tumor cells. The effects of local hyperthermia on the blood flow, oxygen pressure and pH in tissues were investigated using AH-100B tumor bearing rats, by immersing the tumor in a water bath at 41 degrees, 43 degrees and 45 degrees C. These parameters were measured in the marginal and deeper sites of the tumor mass, and in the normal muscle adjacent to the tumor. During immersion at 41 degrees C, blood flow in the tissue was increased at each site, and during immersion at 43 degrees C, tissue blood flow increased initially at each site, but decreased with time to rates below that of the unheated tissue. During immersion at 45 degrees C, the blood flow decreased markedly in each tissue. The changes in oxygen pressure and pH in each tissue were similar to those observed in the blood flow during localized heating at 41 degrees, 43 degrees and 45 degrees C. In local thermochemotherapy, the initial stage of hyperthermic treatment seems to be the most suitable time for administering carcinostatics, since it is the time when tumor blood flow has not yet decreased.

Animals↗

PubMed1988

The effects of diet on the residual small intestine following massive resection.

The midportions of rat small intestines were resected by 90 per cent, and the residual intestines studied for the effects of diet on mucosal morphology, nutrition and gastrointestinal hormones. Groups of rats were fed chow, an elemental diet (ED), or an ED + dietary fiber (EDF) for 1 or 3 weeks. Nonresected rats which were fed chow or ED for 3 weeks were used as controls. Nutritional parameters, such as concentrations of serum total protein, albumin and transferrin were favorable but gain in body weight was not. The parameters indicated that resected rats fed EDF fared better than resected rats fed ED. Mucosal villous height in the residual jejunum, similar in all the resected groups after 1 week, was significantly increased in the resected rats fed chow or EDF after 3 weeks, but did not differ between 1 and 3 weeks in the resected rats fed ED. Changes in the number of villous epithelial cells and villous width were also examined. The level of plasma enteroglucagon was high in the rats fed chow or EDF after both 1 and 3 weeks, and was positively correlated with the increases in villous height. Levels of serum gastrin were not affected by dietary change. Luminal nutrients were significantly associated with the adaptive changes in the mucosa of the residual intestine, and mucosal morphology was also considerably influenced by dietary change.

Adaptation, Physiological↗

PubMed1988

A comparison of pelvic retroperitoneal pneumography and computed tomography in the assessment of extramural invasion of rectal carcinoma.

Pelvic retroperitoneal pneumography (PRP) and pelvic computed tomography (CT) were performed on 33 patients with rectal carcinoma in order to compare the usefulness of the two diagnostic procedures in the preoperative assessment of local malignant extramural invasion. Six PRP-negative patients in whom no free air was visualized in the retroperitoneal space surrounding the mass, were all assessed as having extramural invasion by CT scan and all had histologic evidence of invasion. Of 27 PRP-positive patients in whom free air was seen surrounding the mass, 18 were diagnosed as having extramural invasion on CT, 15 of whom had histologic proof of invasion. In the remaining 9 PRP-positive patients, there was no evidence of extramural invasion on the CT scans, but 5 patients showed evidence of invasion histologically. PRP, when positive, had an unacceptably high rate of being false positive and was therefore unreliable in assessing extramural invasion, whereas CT was able to detect, to some extent, extramural invasion which PRP failed to demonstrate. Based on these findings, we conclude that CT is more useful than PRP in the preoperative assessment of extramural invasion of rectal carcinoma, but is of limited diagnostic value when negative.

Adult↗

PubMed1988

Increased proportion of proapolipoprotein A-I in HDL from patients with liver cirrhosis and hepatitis.

We examined the isoform pattern of apolipoprotein A-I (apo A-I) in high density lipoprotein from patients with liver disease. An increase in the proportion of proapo A-I was evident in patients with decompensated liver cirrhosis, acute hepatitis and hepatocellular carcinoma. The rate of conversion from proapo A-I to apo A-I was low in sera from those with liver disease, compared to normal controls. The proportion of proapo A-I showed a tendency toward increase with advance in liver damage. These results suggest that the liver is participating in the reaction converting proapo A-I to the mature apo A-I.

Apolipoprotein A-I↗

PubMed1988

Effects of insulin, dexamethasone and glucagon on the production of apolipoprotein A-I in cultured rat hepatocytes.

Cultured rat hepatocytes were used to study the effects of hormones on the production of apo A-I. In addition, we compared these effects with the production of albumin. Hepatocytes were isolated from normal adult rat livers and cultured in MEM, as nearly confluent monolayers. In the absence of hormones, apo A-I and albumin accumulated in the culture medium almost linearly for periods up to 24 h. The rates of accumulation of apo A-I and albumin in the medium were 22 ng/mg cell protein per h and 1.2 micrograms/mg cell protein per h, respectively. During the incubations the cellular contents of apo A-I remained constant. Insulin stimulated the production of albumin at concentrations over 10(-10) M, but inhibited the production of apo A-I at concentrations over 10(-8) M. Dexamethasone showed no significant effects on albumin production but stimulated apo A-I production at concentrations over 10(-6) M. Glucagon inhibited the production of albumin and apo A-I dose-dependently at concentrations over 10(-10) M. Thus, the production of albumin and apo A-I are presumably controlled by different regulatory mechanisms.

Albumins↗

PubMed1988

Phenotypes of apolipoprotein E and abnormalities in lipid metabolism in patients with non-insulin-dependent diabetes mellitus.

Phenotypic expressions of apolipoprotein E (apo E) were studied in 94 Japanese patients with non-insulin-dependent diabetes mellitus (NIDDM) and in 91 normal controls. The apo E gene frequencies observed in patients with NIDDM (epsilon 4, 0.101; epsilon 3, 0.824; and epsilon 2, 0.075) were not significantly different from those in normal controls (epsilon 4, 0.093; epsilon 3, 0.863; and epsilon 2, 0.044). Subgrouping the diabetic patients with and without hyperlipidemia, the epsilon 2 allele was significantly more frequent in patients with hypertriglyceridemia. The levels of serum triglyceride, very low density lipoprotein-cholesterol (VLDL-C), and VLDL-triglyceride (VLDL-TG) were significantly higher in patients with the epsilon 2 heterozygote than in those without the epsilon 2 allele (P less than .01). The results suggest that variation in the apo E gene may be one factor related to the hypertriglyceridemia present in patients with NIDDM.

Adolescent↗

PubMed1988

Intra-hepato-arterial chemotherapy with CDDP and 5-FU for metastases to the liver from colorectal and gastric cancers.

Thirty-five patients with metastases to the liver from colorectal (26 patients) and gastric (nine patients) cancers were treated with intra-hepato-arterial (IHA) injections of cis-diamminedichloroplatinum (II) (CDDP) plus 5-fluorouracil (5-FU). Therapeutic schedules consisted of manual bolus injections of CDDP. (25-35 mg/m2/week) and 5-FU (150-180 mg/m2/day) Regimen I, and CDDP (25-35 mg/m2/10-14 days) and 5-FU (60-70 mg/m2/day Regimen II. In patients with colorectal cancer metastatic to the liver, partial response (PR) rates in Regimens I and II were 38% and 62%, respectively. By contrast, in patients with metastases to the liver from gastric cancer, a PR was obtained in only one of nine patients (11%). IHA chemotherapy CDDP plus 5-FU, especially following Regimen II, appears to be a strongly recommendable strategy for treatment of metastatic liver tumors derived from colorectal cancer.

Adult↗

PubMed1988

Comparative study of gastric cancer in young and aged patients.

Clinical and pathological findings of gastric cancer in patients of less than 30 years of age were compared with those in aged patients of over 75 years of age. These were 10 males and 24 females, and the rate of gastric cancer for females in the younger group was extremely high. There were marked differences between both groups in the pathological findings of gastric cancer, and consequently in the progressive pattern of the disease, perhaps as the result of differences in the matrix of cancer development and the influence of sex hormones. Gastric cancer at an advanced stage and delayed surgery in younger patients are attributable to negligence on the part of the patient in scheduling a medical examination and careless diagnosis by the physician. However, the prognosis of gastric cancer was not unfavorable in the younger patients when curative surgery was performed.

Adolescent↗

PubMed1988

Cocarcinogenic activity of bile acids in the chemical transformation of C3H/10T1/2 fibroblasts in vitro.

We have performed a series of experiments to determine directly whether bile acids influence carcinogenesis, using a C3H/10T1/2 cell transformation system in vitro. Treatment of the cells with the carcinogen, 3-methylcholanthrene (MCA), followed by the addition of lithocholic acid (LCA), produced a marked increase in the number of transformed foci as compared to the number induced by MCA alone. Simultaneous treatment with MCA and bile acid did not increase the number of transformed foci except in the case of MCA in combination with LCA. When cultured cells were exposed to MCA soon after removal of cholic acid or LCA, a statistically significant increase in the number of transformed foci was noted. When cultured cells were replated after continuous exposure to test compounds and then treated with MCA, no enhancement of the rate of formation of transformed colonies was observed. From these results, it appears that bile acids act as not only promoting but also as co-carcinogenic agents under certain circumstances.

Animals↗

PubMed1988

Thermochemosensitivity: augmentation by hyperthermia of cytotoxicity of anticancer drugs against human colorectal cancers, measured by the human tumor clonogenic assay.

Thermochemosensitivity was examined in vitro by a human tumor clonogenic assay (HTCA) using specimens obtained surgically from 43 patients with colorectal cancer. We found that the percentages of patients whose cells showed higher sensitivity (greater than 70% inhibition of colony formation) to hyperthermia alone were 29.6 and 55.6% at 42 and 43 degrees C each for 1 h, respectively. Similarly, percentages of patients whose cells were sensitive to drugs alone were 13.8, 24.1 and 48.3%, for cis-diamminedichloroplatinum(II), 5-fluorouracil and mitomycin C, respectively. These sensitivities were augmented when hyperthermia was combined with administration of anticancer agents. Even in tumor cells that were insensitive to anticancer drugs alone or to hyperthermia alone, sensitivity was enhanced when administration of drugs was combined with hyperthermia. Our results demonstrate that HTCA of tumor cells, obtained from suitable patients, may be useful as a predictive test for application of thermotherapy and for individualization of chemotherapy.

Antineoplastic Agents↗

PubMed1988

Physiological significance of fetal blood gas changes elicited by different delivery postures.

We performed umbilical blood gas analysis for 130 pregnant women in sitting and for 50 in supine position immediately after their deliveries. To elucidate whether fetal blood gas changes were attributed to the maternal postures, we also carried out the maternal blood gas analysis during delivery (n = 145) and prior to the onset of labor (n = 100) in both positions. Blood gas values of the umbilical vein and artery in the sitting group were significantly higher in pH, PO2, base excess (BE) and oxygen saturation (SO2), and lower in PCO2 than those in the supine group. In contrast, maternal blood gas values (pH, PaCO2, PaO2 and SaO2) did not show significant differences between these two groups in both during delivery and before the onset of labor. Thus, the sitting delivery position can elicit physiologically more beneficial blood gas aspects in fetus compared with the conventional supine delivery position. Umbilical blood gas improvements induced by sitting delivery position do not appear to be a result of the maternal blood gas alteration, but appear to be mediated by other factors.

Carbon Dioxide↗

PubMed1988

[Evaluation of the system performance and clinical images of the single photon emission computed tomography for head using ring arranged detector].

To evaluate the system performance, several preoperational fundamental tests of single photon emission computed tomography (SPECT) were carried out. Spatial resolutions (FWHM) measured with the point-spread functions of a 99mTc line source were 12.5 mm with a high resolution (HR) collimator and 17.2 mm with a high sensitivity (HS) collimator respectively. Slice thicknesses (FWHM) obtained from the profile curves of slice images were 17.5 mm (HR) and 29.0 mm (HS) at the center of rotation. System sensitivities were 5.4 kcps/slice (HR) and 27.8 kcps/slice (HS). Uniformities calculated from the SPECT images of a pool phantom were 4.7% (HR) and 2.7% (HS) at the condition of 3,000 kcounts to be acquired. SPECT images of the HEADTOME SET-031 were considered very useful to diagnose the cerebrovascular disease.

Brain↗

PubMed1988

[Acquisition of the control of a novel muscular activity by electromyograph biofeedback].

Present study aimed at to examine the process that people acquire the control of a novel muscular activity, of which they have had little experience of voluntary control, by electromyograph (EMG) biofeedback. Thirty undergraduate students who were unable to move their ears served as subjects. They were asked to give tension unto the m. auricularis posterior (the muscle to draw an ear backward). A factorial design was employed with two levels of strategy (transferring, non-transferring) and three methods of how to provide with the EMG feedback signals from the m. auricularis posterior during training session (no-feedback, biofeedback, intermittent biofeedback). The experiment was consisted of four sessions: rest, pre-test, training, and post-test. Main results were as follows: (1) Two groups, which subjects used the transferring strategy and the feedback signals, significantly increased the integrated EMG of the m. auricuralis posterior from pre- to post-tests. (2) Furthermore, the EMG-increase was significantly greater in one group, which feedback signals were intermittently given at every other training trial, than another group, which feedback signals were given at all trials. (3) It was also found that no increase of awareness to the muscular tension occurred despite the increase of EMG activity.

Adult↗