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Biomedical subjects

I Kodama

Publications and source records attributed to I Kodama.

At least 127 records · Page 7Linked to original sources
PubMed1994

Gastric cancer surgery in patients aged at least 80 years old.

Fifty-six patients with gastric cancer who were at least 80 years of age (range 80-88) (Group 1) were retrospectively investigated and compared with younger patients. The resectability rate was 80% (45/56) in Group 1, 88% (331/373) in Group 2 (patients aged between 70 and 79) and 91% (992/1,087) in Group 3 (patients aged under 70 years). Of the cases resected, 73% had advanced cancer in Group 1, 61% in Group 2 and 55% in Group 3. Total gastrectomy was performed in only 11% of the resected cases in Group 1, in 25% of those in Group 2 and in 33% in Group 3. Of these, combined resections were employed in none of the patients in Group 1, in 38% of those in Group 2 and in 47% of those in Group 3. Pathologically, 78% of Group 1 cancers were of the differentiated type, 68% of Group 2 and 49% of Group 3 cancers (Group 1: Group 3, p < 0.001). R3 gastrectomy was performed for advanced cancer in none of the patients in Group 1, in 21% in Group 2, and in 39% of those in Group 3. In resected early cancers, the lymph node metastasis (n) rate was 0% for Group 1, 10% for Group 2, and 9% for Group 3. In the advanced cases, n(+) was 67% for Group 1, 65% for Group 2, and 73% for Group 3. Postoperative complications occurred in 25% of Group 1 and in 12% of Group 2 patients. Anastomotic leakage occurred in 4% of Group 1 and in 5% of Group 2 patients. The 5-year-survival rate was 47% for all resected cases in Group 1, and 68% for Groups 2 and 3.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1994

[Complete response in a case of unresectable gastric cancer treated by combined chemoimmunotherapy of MMC, 5-FU and OK-432].

A 68-year-old female patient with unresectable advanced gastric cancer was treated by combined administration of MMC (10 mg/month), 5-FU (200 mg/day) and OK-432 (5KE/2 weeks). Two months after starting the treatment, there was a diminution in the serum CEA level. Six months later, the CEA had decreased to the normal level, primary and metastatic sites completely disappeared and no cancer cell was confirmed by endoscopic biopsy. The patient has survived for 33 months of a state of complete response.

Adenocarcinoma↗
PubMed1993

Deferoxamine reduces the reperfusion injury in isolated neonatal rabbit hearts after hypothermic preservation.

The protective action of deferoxamine, an iron chelator, against reperfusion injury following hypothermic preservation was investigated in the Langendorff-perfused hearts of neonatal rabbits. Left ventricular function and radical generation were used as parameters to evaluate functional and metabolic changes. The free radicals in coronary effluents were measured with an electron spin resonance spectroscope using a spin trapping agent, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). The hearts were preserved in cold St. Thomas solution at 4 degrees C for 6 h following cardiac arrest, then reperfused with oxygenated Krebs-Henseleit solution in a control. Deferoxamine (100 microM) was added to the perfusate just prior to reperfusion in group I, and 3 min after the start of reperfusion in group II. In the control group, the left ventricular developed pressure (LVDP) after 30-min reperfusion recovered up to 43.5 +/- 3.1% (mean +/- SD, n = 5) the preischemic value. Group I showed a significant improvement in LVDP recovery after 30-min reperfusion at 57.1 +/- 3.1% (P < 0.01 vs control), but group II did not (47.5 +/- 2.3%). When a burst of DMPO-OH signals was detected during the initial 5 min of reperfusion, the signal intensity in group I was significantly reduced to about 35-40% of the control value. Group II showed a similar intensity to the control group. Thus, we conclude that deferoxamine may exert a protective action against the dysfunction of neonatal mammalian hearts induced by preservation-reperfusion through an inhibition of iron-catalyzed radical formation.

Animals↗
PubMed1993

Contribution of potassium accumulation in narrow extracellular spaces to the genesis of nicorandil-induced large inward tail current in guinea-pig ventricular cells.

The mechanism of nicorandil-induced large inward tail current (Itail) in single guinea-pig ventricular cells was investigated using the whole-cell patch-clamp technique. In the presence of 0.5-1.0 mM nicorandil, an activator of adenosine 5'-triphosphate (ATP)-sensitive K+ current (IKATP), a depolarization pulse causing a large outward current was followed by a large inward Itail on the repolarization step to the holding potential at -85 mV. The larger the outward current, the greater the Itail. The amplitude of Itail increased as a single exponential function (tau = 74.9 ms) as the duration of preceding depolarization was prolonged. Both the outward current and Itail were inhibited nearly completely after application of glibenclamide (1 microM), a specific blocker of IKATP. Substitution of K+ with Cs+ in both the external and internal solutions resulted in a virtual elimination of Itail. Itail was well preserved under the condition where Ca2+ entry during the preceding depolarization was largely inhibited or where external Na+ was replaced by Li+. A transient positive shift of reversal potential for the net current was observed at the peak of Itail). At 30 mM external K+ concentration, Itail was almost eliminated. From these findings, its is concluded that the Itail is a K+ current associated with an alteration of the K+ equilibrium potential (EK) following a substantial K+ efflux. This EK change is most likely explained by an accumulation of K+ in transverse tubules (T-tubules) since Itail was not induced in atrial cells in which T-tubules are poorly developed.

Adenosine Triphosphate↗
PubMed1993

Effect of perfusion and blood content on ultrasonic backscattering of liver tissue.

The purpose of this study was to determine the effect of blood flow perfusion and red cell content on ultrasonic scattering by liver tissue. Data acquisition for ultrasonic tissue characterization (UTC) employing analysis of the backscattered echoes from the power spectrum was obtained from the same region of pig liver tissue under four conditions: 1) normal perfusion in situ, 2) ischemia in situ in the living pig, 3) ischemia in situ immediately postmortem, and 4) immediately after excision of the liver. Discriminant function analysis was used to evaluate differences in the two basic parameters from the normalized power spectrum: slope and intercept. Normal perfused liver had significantly higher intercept values and lower slope values than liver under the other three conditions. Excised liver showed the lowest intercept and highest slope values (p < 0.01). These experiments indicate that differences in perfusion produce significant differences in ultrasonic scattering by liver tissue (ischemia caused a 3 dB drop in intercept amplitude). Normal or ischemic in vivo and in vitro liver tissue is associated with different patterns of ultrasonic scattering, and scattering data under these various circumstances are not equivalent.

Animals↗
PubMed1993

Age determination of experimental venous thrombi by ultrasonic tissue characterization.

PURPOSE: The ability of ultrasonic tissue characterization based on radiofrequency signal processing to detect compositional differences in thrombi of varying ages was evaluated in vivo. METHODS: Thrombi were produced in 49 jugular veins of 26 anesthetized 18 to 20 kg pigs by partial ligation and application of direct electric current. Thrombi were imaged 30 minutes after formation and 1, 7, and 14 days later with a color Doppler ultrasound scanner that identified the thrombi, and acquired radio frequency data for ultrasonic tissue characterization analysis. Ultrasonic tissue characterization used two parameters from the normalized power spectrum, slope, and intercept, which are related to scatterer size, scatterer concentration, and acoustic-impedance differences between scatterers and surrounding medium. Previous in vitro studies demonstrated that lower slope and higher intercept values correlated with greater cellularity and more-dense fibrin mesh. Histologic examination was performed for each time period. The values of slope and intercept for each timed observation were compared by a multilinear discriminant analysis. RESULTS: There were no statistical differences between day 0 and day 1. Statistically-significant differences in ultrasonic tissue characterization parameters were seen between all other time intervals with p values < 0.01. Older thrombi tended to demonstrate higher slope and lower intercept values. These ultrasonic tissue characterization changes correlated with a red cell and fibrin-mesh density reduction, which was confirmed by histologic findings and was indicative of partial spontaneous thrombolysis. The degree of spontaneous thrombolysis provides an estimate of the age of thrombi. CONCLUSION: Ultrasonic tissue characterization is capable of distinguishing age differences in thrombi in an animal model and has the potential for noninvasive application in clinical diagnosis.

Animals↗
PubMed1993

Role of platelet activating factor in ischaemia-reperfusion injury of isolated rabbit hearts: protective effect of a specific platelet activating factor antagonist, TCV-309.

OBJECTIVES: The aims were to confirm that platelet activating factor is released during reperfusion after global ischaemia in isolated blood perfused rabbit hearts, and to examine the protective action of TCV-309, a platelet activating factor antagonist, against reperfusion injury of cardiac muscle. METHODS: The hearts were mounted on a Langendorff apparatus and perfused with diluted blood perfusate. After cardiac arrest with St Thomas's cardioplegic solution, the hearts were subjected to global ischaemia for 120 minutes at 25 degrees C, and then reperfused for 60 minutes at 37 degrees C. Release of platelet activating factor into the coronary effluent was quantified by radioimmunoassay. The effect of TCV-309 on left ventricular function and release of creatine kinase was measured. RESULTS: A pronounced release of platelet activating factor occurred after the commencement of reperfusion, although it was not detectable before induction of ischaemia. Release of platelet activating factor occurred over 60 minutes of the reperfusion period. In the control, left ventricular developed pressure after 60 minutes of reperfusion recovered to 54.3(SEM 1.7)% (n = 5) of the preischaemic value. In the hearts treated with TCV-309 at concentrations above 0.3 microM, recovery of left ventricular developed pressure was significantly improved (77.6(2.0)% at 1 microM, p < 0.01 v control). Leakage of creatine kinase during the initial five minutes of reperfusion was significantly less in the hearts treated with 1 microM TCV-309 than in the controls (5.2(0.4) v 12.2(1.4) IU.g-1 wet weight, p < 0.01). CONCLUSIONS: Release of platelet activating factor occurred during the reperfusion period in Langendorff perfused hearts. Treatment with the platelet activating factor antagonist TCV-309 significantly improved postischaemic left ventricular function and decreased creatine kinase release. These results suggest that platelet activating factor is involved in myocardial injury during ischaemia-reperfusion.

Animals↗
PubMed1993

Para-aortic lymph node dissection for the treatment of advanced gastric cancer.

Para-aortic lymph node (No. 16) metastasis has been accepted as a factor responsible for non-curability in gastric cancer surgery. Recently in Japan, after detailed experimental and clinical studies of the lymph flows from the stomach and/or perigastric nodes to these No. 16 nodes, it is now considered to be curable. From 5 autopsy cases, the mean number of No. 16 nodes has been determined to be 43. The frequency of positive No. 16 metastasis (No. 16(+)) was found to be 24%, occurring in 35 of 144 cases with advanced gastric cancer following R3 gastrectomy plus No. 16 dissection. The 5 year-survival rate of R3+ No. 16 dissection was 70.1% in n1(+), 49.8% in n2(+) and 24.3% in n3(+) and had better prognoses (by Kaplan-Meier statistics) than those without dissection of the No. 16 nodes. Only 37 patients in the Japanese literature have had No. 16 dissections, and were confirmed histologically to have had No. 16(+) and subsequently survived more than 5 years. The number of those surviving No. 16(+) can be expected to increase in the near future with the adoption of R3 gastrectomy plus No. 16 dissection.

Aorta, Abdominal↗
PubMed1993

Early gastric cancer associated with synchronous multiple liver metastasis--two rare cases.

From 1976 to 1991, 1,640 cases of gastric cancer were resected in our department. Of these, 659 (40.2%) cases were early gastric cancer (EGC). The prognosis after resection of an EGC is generally good, with a 5-year survival rate of 95%. The incidence of an EGC with synchronous liver metastasis is very rare. To our knowledge, only 15 cases of an EGC with synchronous liver metastasis have been reported in the Japanese literature. From 10 cases adequately described the EGC with synchronous liver metastasis derived only from sm-cancers (cancers confined to the submucosa) of medullary type, histologically, more commonly occurring in males than EGC generally, (of elevated type) and with positive lymph node metastasis. Here we report two additional rare cases of EGC with liver metastasis.

Aged↗
PubMed1993

Early gastric cancer with juxta lymph node (n3) metastasis.

From 1976 to 1992, a total of 714 cases of early gastric cancer (EGC) were treated by resection in the First Department of Surgery, Kurume University Hospital. For EGC, the overall lymph node metastasis rate is generally 10%, with the lymph node metastasis observed mainly in the Group 1 perigastric nodes in both mucosal cancer and submucosal cancer. Three rare cases of an early gastric cancer with Group 3 juxta regional lymph node metastasis are described because Group 3 lymph nodes are rarely discovered. To our knowledge, only 14 other cases of EGC with juxta regional lymph node metastasis have been reported in the Japanese literature.

Aged↗
PubMed1993

Retrospective studies of synchronous double early gastric cancer.

From 1984 to 1990, 922 cases of gastric cancer underwent resection in the First Department of Surgery, at Kurume University Hospital. Of these, 381 (41.3%) cases were early gastric cancer (EGC). Among these EGC, synchronous double early gastric cancer (double EGC), according to the diagnostic criteria of Moertel, was found in 49 (12.9%) cases involving 98 foci. In cases of a double EGC, the primary and secondary foci can be distinguished. Double EGC occurred more frequently in males than females (7.1:1). In the elderly, the incidence of a double EGC was higher than the incidence of a single EGC. Double EGC occurred more frequently in the lower third of the stomach than a single EGC. And a macroscopically elevated and histologically differentiated type primary focus was more frequently found in double EGC than in single EGC. Of the 49 secondary foci in the double EGC, 12 (24.5%) foci were a microcarcinoma of less than 5 mm in greatest diameter, and 48 (98%) were limited to the mucosa (m-cancer). Therefore, a preoperative detailed examination of the whole stomach by endoscopy and an intraoperative careful search under gastrotomy must be made in the remnant of the stomach in cases of distal or proximal partial gastrectomy to ensure adequate excision.

Aged↗
PubMed1993

[Expression of the growth factors (EGF, EGFR, and TGF alpha) and PCNA in superspreading and penetrating types of gastric carcinomas].

Expression of EGF, EGFR, TGF alpha, and PCNA in resected gastric carcinomas (15 cases of superspreading type and 25 cases of penetrating type) was immunohistochemically studied to understand biological features of these two types of gastric carcinomas. EGF, EGFR, and TGF alpha positive cases were preferentially found in the penetrating type rather than in the superspreading type (p < 0.05). Incidence of PCNA high expression cases in the penetrating type was significantly higher than that in superspreading type. Nineteen cases (76%) of the penetrating type and 1 case of the superspreading type (6.7%) were diffusely PCNA (+), and the incidence of in the former type was significantly higher than that of the latter type (p < 0.001). One case of the superspreading type and 13 cases of the penetrating type were either EGF (+) or TGF alpha (+), and EGFR (+), and the incidence in the latter type was significantly higher than that in the former type (p < 0.05), suggesting that growth and invasion of carcinoma cells, especially in the penetrating type, may depend on "autocrine mechanism". Incidence of the growth factors (+) and PCNA (+) cells in classical type of signet ring cells was lower than that in other types of singnet ring cells.

Carcinoma, Signet Ring Cell↗
PubMed1993

Protective effects of diltiazem and ryanodine against ischemia-reperfusion injury in neonatal rabbit hearts.

The effects of diltiazem, a sarcolemmal Ca2+ channel blocker, and ryanodine, an inhibitor of sarcoplasmic reticulum function, were investigated in isolated newborn rabbit hearts (2 to 5 days old) subjected to ischemia and reperfusion. After cardioplegic arrest with St. Thomas' Hospital solution, global ischemia was induced at 37 degrees C (normothermia) for 45 minutes or at 20 degrees C (hypothermia) for 180 minutes. The hearts were then reperfused at 37 degrees C for 30 minutes. Diltiazem or ryanodine, at concentrations that have minimal to moderately negative inotropic effects under nonischemic conditions, was added to the cardioplegic solution. After normothermic ischemia, reperfusion of untreated hearts resulted in recovery of left ventricular developed pressure to 52.9% +/- 2.5% of the preischemic level. In hearts treated with diltiazem, recovery of left ventricular developed pressure was significantly improved (84.2% +/- 2.9% at 3 x 10(-8) mol/L; p < 0.01). Comparable improvement was achieved with ryanodine (90.5% +/- 4.1% at 10(-9) mol/L; p < 0.01). Creatine kinase leakage and structural derangement of mitochondria were also reduced by both agents. With hypothermic ischemia, left ventricular developed pressure recovered in untreated hearts to 72.7% +/- 3.3% of preischemic values. Treatment with diltiazem improved the recovery of left ventricular developed pressure to 96.9% +/- 3.5% at 3 x 10(-8) mol/L and reduced creatine kinase leakage and mitochondrial damage. Ryanodine also improved the recovery of left ventricular developed pressure and attenuated ultrastructural damage. These findings suggest that Ca2+ handling by the sarcoplasmic reticulum, like transsarcolemmal Ca2+ influx, plays an important role in the pathogenesis of myocardial ischemia-reperfusion injury in the neonatal heart despite the morphologic and functional immaturity of the sarcoplasmic reticulum in the neonate.

Animals↗
PubMed1993

[A case of advanced gastric cancer with liver and lung metastasis effectively treated by combined chemo-immunotherapy of MMC, 5'-DFUR, OK-432].

A sixty-eight-year-old male patient was diagnosed as having inoperable advanced gastric cancer with liver and lung metastasis. The patient was treated by combined chemo-immunotherapy of MMC 10 mg/M, 5'-DFUR 800 mg/day and OK-432 5 KE/2 W. Six months after commencing chemotherapy, CT-scan and upper GI series revealed that metasized liver tumors and stomach lesion were remarkably decreased in size and no cancer cell was confirmed by endoscopic biopsy. Further, the metastatic lung tumor has disappeared on chest X-ray. The patient had been well without any evidence of tumor re-progression for over one year, but from July the liver tumor began to metastasize again and the patient eventually died of liver metastasis on Jan. 1, 1993.

Adenocarcinoma↗
PubMed1993

[Molecular and biophysical aspects of cardiac Na channel].

Voltage-dependent ion channels mediate action potential and conduction in cardiac cells. In the past ten years, their single channel properties and protein components have been identified, isolated and restored to functional form in the purified state. Na channel has a primary alpha subunit, which is composed of four homologous domains, each of which has six transmembrane segments. Site-directed mutation has probed the function of specific regions or even of single amino acids. The ion-conducting pore, molecular voltmeter, ion filter and regulatory system of sodium channel have been characterized by coordination of biophysical, biochemical and molecular genetic methods.

Humans↗
PubMed1992

Deferoxamine, an iron chelator, reduces myocardial injury and free radical generation in isolated neonatal rabbit hearts subjected to global ischaemia-reperfusion.

The protective action of deferoxamine, an iron chelator, against functional and metabolic deteriorations of ventricular muscle, induced by ischaemia-reperfusion, was investigated in Langendorff-perfused hearts of neonatal rabbits in comparison with superoxide dismutase (SOD) plus catalase. The perfused hearts were subjected to normothermic (37 degrees C) global ischaemia for 45 min following cardiac arrest with St Thomas cardioplegic solution and then reperfused with oxygenated Krebs-Henseleit solution. In control hearts, the recovery of the left ventricular developed pressure (LVDP) after 30 min reperfusion was 50.7 +/- 3.1% (mean +/- SE, n = 5) of the pre-ischaemic value. The LVDP recovery was significantly improved in the hearts treated with deferoxamine at 10-100 microM (89.4 +/- 1.4% at 30 microM, P < 0.01 vs. control). The improvement in LVDP was less prominent when treated with 30 x 10(4) U/l SOD plus 30 x 10(4) U/l catalase (67.9 +/- 2.0%, P < 0.01 vs. deferoxamine at 30 microM). CPK leakage into the coronary effluent during the initial 5 min of reperfusion was reduced to around half of the control value with 30 microM deferoxamine (P < 0.05 vs. control), while unaffected by the addition of SOD plus catalase. Free radicals in the coronary effluent were measured with electron spin resonance spectroscopy in separate experiments by using a spin-trapping agent, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). A burst of DMPO-OH signal was detected during the initial minutes of reperfusion. The intensity of DMPO-OH signal was significantly reduced by 30 microM deferoxamine to about one-third of control.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗