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K Yasuda

Publications and source records attributed to K Yasuda.

At least 91 records · Page 5Linked to original sources
PubMed2001

Potent and selective ET-A antagonists. 1. Syntheses and structure-activity relationships of N-(6-(2-(aryloxy)ethoxy)-4-pyrimidinyl)sulfonamide derivatives.

Modifications to the ET(A/B) mixed type compounds 1 (Ro. 46-2005) and 2 (bosentan) were performed. Introduction of a pyrimidine group into 1 resulted in a dramatic increase in affinity for the ET(A) receptor, and the subsequent optimization of substituents on the pyrimidine ring led us to the discovery of N-(6-(2-((5-bromo-2-pyrimidinyl)oxy)ethoxy)-5-(4-methylphenyl)-4-pyrimidinyl)-4-tert-butylbenzenesulfonamide (7k), which showed an extremely high affinity for the human cloned ET(A) receptor (K(i) = 0.0042 +/- 0.0038 nM) and an ET(A/B) receptor selectivity up to 29 000 (K(i) = 130 +/- 50 nM for the human cloned ET(B) receptor). The compound was designed on the hypothesis that the hydrogen atom of the hydroxyl group in 1 and 2 played a role not as a proton donor but as an acceptor in the possible hydrogen bonding with Tyr129. Since the incorporation of a pyrimidinyl group into the hydroxyethoxy side chain of the nonselective antagonist (1) dramatically enhanced both the ET(A) receptor affinity and selectivity, and since similar results were obtained from the benzene analogues, we put forward the hypothesis that a "pyrimidine binding pocket" might exist in the ET(A) receptor.

Animals↗
PubMed2001

Severely impaired cardiac autonomic nervous activity after the Fontan operation.

BACKGROUND: Elevated neurohumoral activity and an abnormal cardiopulmonary response to exercise are well-established characteristics in patients after the Fontan operation. However, there have been few studies addressing cardiac autonomic nervous activity (CANA) in these patients. METHODS AND RESULTS: We evaluated CANA in 63 post-Fontan patients and 44 controls. Cardiac parasympathetic nervous activity (PSNA) was estimated by heart rate (HR) changes after cholinergic blockade, HR variability, and arterial baroreflex sensitivity. Cardiac sympathetic nervous activity was estimated by the heart to mediastinum [(123)I]metaiodobenzylguanidine activity ratio (H/M) and the HR increase (DeltaHR) after isoproterenol infusion (beta). DeltaHR and peak oxygen uptake (VO(2)) were measured by exercise test. There was no difference in beta between the Fontan group and controls. PSNA and H/M were markedly lower than in controls (P<0.001). PSNA and beta were related to DeltaHR (P<0.05); however, peak VO(2) was not correlated with DeltaHR. Neither PSNA nor H/M was associated with clinical features, including hemodynamics, type of repair, number of surgical procedures, age at Fontan operation, or follow-up period, and administration of an angiotensin-converting enzyme inhibitor did not improve the impaired CANA in these patients. CONCLUSIONS: After the Fontan procedure, postsynaptic beta-sensitivity is maintained and is important in DeltaHR during exercise as is PSNA, although DeltaHR does not determine exercise capacity. The lack of a relationship between CANA and clinical features implies that, in addition to surgical damage, the Fontan circulation per se may impair CANA. Angiotensin-converting enzyme inhibitor administration does not change this abnormality.

Adolescent↗
PubMed2001

Cessation of chronic nicotine administration enhances wet-dog shake responses to 5-HT2 receptor stimulation in rats.

RATIONALE: The involvement of central serotonergic systems has been hypothesized clinically to contribute to nicotine withdrawal symptoms. However, involvement of the serotonin2 (5-HT(2)) receptor system in nicotine withdrawal is not clear. OBJECTIVES: The changes in wet-dog shake responses induced by (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a selective 5-HT(2) receptor agonist, following nicotine cessation was investigated in rats. METHODS: DOI (1 mg/kg SC) was administered 24 h after the final treatment of saline or nicotine (0.5 mg/kg per day SC) for 7 or 21 days. RESULTS: Cessation of nicotine administration for 7 or 21 days increased DOI-induced wet-dog shake responses. A single administration of nicotine (0.5 mg/kg SC) had no effect on DOI-induced wet-dog shakes. The enhancement by the cessation of nicotine treatment for 7 days was abolished by coadministration of nicotine. Mecamylamine (3 mg/kg IP), a nicotinic receptor antagonist, precipitated DOI-induced wet-dog shake responses in rats chronically treated with nicotine but not with saline. CONCLUSIONS: These findings suggest that cessation of chronic nicotine produced increased sensitivity to 5-HT(2) receptor systems, and that the 5-HT(2) receptor systems may be involved in the nicotine withdrawal symptoms.

Amphetamines↗
PubMed2001

A defect in the cytochrome b large subunit in complex II causes both superoxide anion overproduction and abnormal energy metabolism in Caenorhabditis elegans.

A mev-1(kn1) mutant of the nematode Caenorhabditis elegans is defective in the cytochrome b large subunit (Cyt-1/ceSDHC) in complex II of the mitochondrial electron transport chain. We have previously shown that a mutation in mev-1 causes shortened life span and rapid accumulation of aging markers such as fluorescent materials and protein carbonyls in an oxygen-dependent fashion. However, it remains unclear as to whether this hypersensitivity is caused by direct toxicity of the exogenous oxygen or by the damage of endogenous reactive oxygen species derived from mitochondria. Here we report important biochemical changes in mev-1 animals that serve to explain their abnormalities under normoxic conditions: (i) an overproduction of superoxide anion from mitochondria; and (ii) a reciprocal reduction in glutathione content even under atmospheric oxygen. In addition, unlike wild type, the levels of superoxide anion production from mev-1 mitochondria were significantly elevated under hyperoxia. Under normal circumstances, it is well known that superoxide anion is produced at complexes I and III in the electron transport system. Our data suggest that the mev-1(kn1) mutation increases superoxide anion production at complex II itself rather than at complexes I and III. The mev-1 mutant also had a lactate level 2-fold higher than wild type, indicative of lactic acidosis, a hallmark of human mitochondrial diseases. These data indicate that Cyt-1/ceSDHC plays an important role not only in energy metabolism but also in superoxide anion production that is critically involved in sensitivity to atmospheric oxygen.

Adenosine Triphosphate↗
PubMed2001

Disrupted bile acid homeostasis reveals an unexpected interaction among nuclear hormone receptors, transporters, and cytochrome P450.

Sister of P-glycoprotein (SPGP) is the major hepatic bile salt export pump (BSEP). BSEP/SPGP expression varies dramatically among human livers. The potency and hierarchy of bile acids as ligands for the farnesyl/bile acid receptor (FXR/BAR) paralleled their ability to induce BSEP in human hepatocyte cultures. FXR:RXR heterodimers bound to IR1 elements and enhanced bile acid transcriptional activation of the mouse and human BSEP/SPGP promoters. In FXR/BAR nullizygous mice, which have dramatically reduced BSEP/SPGP levels, hepatic CYP3A11 and CYP2B10 were strongly but unexpectedly induced. Notably, the rank order of bile acids as CYP3A4 inducers and activators of pregnane X receptor/steroid and xenobiotic receptor (PXR/SXR) closely paralleled each other but was markedly different from their hierarchy and potency as inducers of BSEP in human hepatocytes. Moreover, the hepatoprotective bile acid ursodeoxycholic acid, which reverses hydrophobic bile acid hepatotoxicity, activates PXR and efficaciously induces CYP3A4 (a bile-metabolizing enzyme) in primary human hepatocytes thus providing one mechanism for its hepatoprotection. Because serum and urinary bile acids increased in FXR/BAR -/- mice, we evaluated hepatic transporters for compensatory changes that might circumvent the profound decrease in BSEP/SPGP. We found weak MRP3 up-regulation. In contrast, MRP4 was substantially increased in the FXR/BAR nullizygous mice and was further elevated by cholic acid. Thus, enhanced hepatocellular concentrations of bile acids, due to the down-regulation of BSEP/SPGP-mediated efflux in FXR nullizygous mice, result in an alternate but apparent compensatory up-regulation of CYP3A, CYP2B, and some ABC transporters that is consistent with activation of PXR/SXR by bile acids.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Thermodynamic stability of base pairs between 2-hydroxyadenine and incoming nucleotides as a determinant of nucleotide incorporation specificity during replication.

We investigated the thermodynamic stability of double-stranded DNAs with an oxidative DNA lesion, 2-hydroxyadenine (2-OH-Ade), in two different sequence contexts (5'-GA*C-3' and 5'-TA*A-3', A* represents 2-OH-Ade). When an A*-N pair (N, any nucleotide base) was located in the center of a duplex, the thermodynamic stabilities of the duplexes were similar for all the natural bases except A (N = T, C and G). On the other hand, for the duplexes with the A*-N pair at the end, which mimic the nucleotide incorporation step, the stabilities of the duplexes were dependent on their sequence. The order of stability is T > G > C >> A in the 5'-GA*C-3' sequences and T > A > C > G in the 5'-TA*A-3' sequences. Because T/G/C and T/A are nucleotides incorporated opposite to 2-OH-Ade in the 5'-GA*C-3' and 5'-TA*A-3' sequences, respectively, these results agree with the tendency of mutagenic misincorporation of the nucleotides opposite to 2-OH-Ade in vitro. Thus, the thermodynamic stability of the A*-N base pair may be an important factor for the mutation spectra of 2-OH-Ade.

Base Pairing↗
PubMed2001

On-chip culture system for observation of isolated individual cells.

To investigate the properties of isolated single cells with their environment, we developed the differential analysis method for single cells using an on-chip microculture system. The advantages of the system are, (i). continuous cultivation of a series of isolated single cells or a group of cells under contamination free conditions, (ii). continuous observation and comparison of those cells with 0.2 microm spatial resolution by a phase-contrast/fluorescent microscopy system with digital image processing. The core of the system is an n x n (n = 20-50) array of chambers, where each is 20-70 microm in diameter and 5-30 microm deep holes etched into a biotin-coated 0.17 mm thick glass slide. The biotin-coated glass slide is covered with the streptavidin coated cellulose semipermeable membrane, which is fixed on the surface of the glass slide by streptavidin-biotin attachment, separating those holes from the nutrient medium circulating through a 'cover chamber' above. A single cell or group of cells can thus be isolated from environment perfused with the same medium, and the medium in each chamber can be changed within the diffusion time (<1/30 s). In addition, the microchamber volumes of specific cells or cell groups can be controlled by the sizes of the chambers. By using this system we found that the length of isolated Escherichia coli increased at 0.06 microm min(-1) between cell divisions regardless of the chamber volume, and that the cell concentration reached 10(12) cells ml(-1) under contamination free conditions. The system is thus particularly useful for one cell level analysis because the direct descendants of single cells can be cultured and compared in the isolated microchambers, and the physical properties of the cells in each microchamber can be continuously observed and compared.

Buffers↗
PubMed2001

Stabilization factors affecting duplex formation of peptide nucleic acid with DNA.

Peptide nucleic acid (PNA) is an oligonucleotide analogue in which the sugar-phosphate backbone is replaced by an N-(2-aminoethyl)glycine unit to which the nucleobases are attached. We investigated the thermodynamic behavior of PNA/DNA hybrid duplexes with identical nearest neighbors but with different sequences and chain lengths (5, 6, 7, 8, 10, 12, and 16 mers) to reveal whether the nearest-neighbor model is valid for the PNA/DNA duplex stability. CD spectra of 6, 7, and 8 mer PNA/DNA duplexes showed similar signal, while 10, 12, and 16 mer duplexes did not. The average difference in Delta G degrees (37) for short PNA/DNA duplexes with identical nearest-neighbor pairs was only 3.5%, whereas that of longer duplexes (10, 12, and 16 mers) was 16.4%. Therefore, the nearest-neighbor model seems to be useful at least for the short PNA/DNA duplexes. Thermodynamics of PNA/DNA duplexes containing 1--3 bulge residues were also studied. While the stability of the 12 mer DNA/DNA duplex decreased as the number of bulge bases increases, the number of bulge bases in PNA/DNA unchanged the duplex stability. Thus, the influence of bulge insertion in the PNA/DNA duplexes is different from that of a DNA/DNA duplex. This might be due to the different base geometry in a helix which may potentially make hydrogen bonds in a base pair and stacking interaction unfavorable compared with DNA/DNA duplexes.

Base Composition↗
PubMed2001

Modulation of hypoglossal motoneuron excitability by NK1 receptor activation in neonatal mice in vitro.

1. The effects of substance P (SP), acting at NK1 receptors, on the excitability and inspiratory activity of hypoglossal (XII) motoneurons (MNs) were investigated using rhythmically active medullary-slice preparations from neonatal mice (postnatal day 0-3). 2. Local application of the NK1 agonist [SAR(9),Met (O(2))(11)]-SP (SP(NK1)) produced a dose-dependent, spantide- (a non-specific NK receptor antagonist) and GR82334-(an NK1 antagonist) sensitive increase in inspiratory burst amplitude recorded from XII nerves. 3. Under current clamp, SP(NK1) significantly depolarized XII MNs, potentiated repetitive firing responses to injected currents and produced a leftward shift in the firing frequency-current relationships without affecting slope. 4. Under voltage clamp, SP(NK1) evoked an inward current and increased input resistance, but had no effect on inspiratory synaptic currents. SP(NK1) currents persisted in the presence of TTX, were GR82334 sensitive, were reduced with hyperpolarization and reversed near the expected E(K). 5. Effects of the alpha(1)-noradrenergic receptor agonist phenylephrine (PE) on repetitive firing behaviour were virtually identical to those of SP(NK1). Moreover, SP(NK1) currents were completely occluded by PE, suggesting that common intracellular pathways mediate the actions of NK1 and alpha(1)-noradrenergic receptors. In spite of the similar actions of SP(NK1) and PE on XII MN responses to somally injected current, alpha(1)-noradrenergic receptor activation potentiated inspiratory synaptic currents and was more than twice as effective in potentiating XII nerve inspiratory burst amplitude. 6. GR82334 reduced XII nerve inspiratory burst amplitude and generated a small outward current in XII MNs. These observations, together with the first immunohistochemical evidence in the newborn for SP immunopositive terminals in the vicinity of SP(NK1)-sensitive inspiratory XII MNs, support the endogenous modulation of XII MN excitability by SP. 7. In contrast to phrenic MNs (Ptak et al. 2000), blocking NMDA receptors with AP5 had no effect on the modulation of XII nerve activity by SP(NK1). 8. In conclusion, SP(NK1) modulates XII motoneuron responses to inspiratory drive primarily through inhibition of a resting, postsynaptic K+ leak conductance. The results establish the functional significance of SP in controlling upper airway tone during early postnatal life and indicate differential modulation of motoneurons controlling airway and pump muscles by SP.

Animals↗
PubMed2001

Influence of ventricular morphology on aerobic exercise capacity in patients after the Fontan operation.

OBJECTIVES: This study investigated the influences of ventricular morphology, hemodynamics and clinical findings on exercise capacity in patients after the Fontan operation. BACKGROUND: Determinants of exercise capacity after the Fontan operation remain unclear. METHODS: Peak oxygen uptake (PVo2) was determined in 105 patients by exercise test and compared to hemodynamics and clinical findings. Patients were divided into three groups based on ventricular morphology: those with a right ventricle (group RV), a biventricle (group BV) and a left ventricle (group LV). RESULTS: Ten patients with atrioventricular valve regurgitation (AVVR) or hypoxia exhibited a low PVo2. After excluding these patients, although PVo2 did not correlate with hemodynamics, except ventricular ejection fraction (p < 0.02), it correlated with age at the Fontan operation and exercise test (p < 0.002). The PVo2 was higher in group LV (63+/-9%) than in groups RV (55+/-9%) and BV (55+/-12%) (p < 0.01), while an inverse correlation between PVo2 and age at operation was demonstrated only in group RV (p < 0.05). Groups RV or BV and age at exercise test were associated with a lower PVo2, whereas group LV was an independent predictor of a higher PVo2 (p < 0.01). During 4.2 years of follow-up, a decrease in peak heart rate was related to a decrease in PVo2 (p < 0.05). The PVo2 decreased in group RV (p < 0.01). CONCLUSIONS: In addition to AVVR, hypoxia, and heart rate response, ventricular morphology is related to exercise capacity. Early Fontan operation may be beneficial in terms of exercise capacity, especially in the group RV patients.

Adolescent↗
PubMed2001

A pivotal role of cysteine 3 of Lck tyrosine kinase for localization to glycolipid-enriched microdomains and T cell activation.

Lck, a Src family protein tyrosine kinase (PTKs), is post-translationally modified by palmitoylation, a process thought to regulate the biological function, membrane affinity and glycolipid-enriched microdomain (GEM) localization of this molecule. To examine the importance of palmitoylation sites Cys3 and Cys5 in Lck, one or both of these residues was mutated to serine to create mutants S3, S5, and S3,5, respectively. Immunofluorescence and confocal microscopy of COS-7 cells transfected with these constructs showed that while S5 and S3 localized to the plasma membrane, S3,5 was localized to the cytoplasm, suggesting that palmitoylation at at least one site is essential for membrane localization. Sucrose gradient based fractionation of these mutants expressed in COS-7 cells showed that while S5 localized to GEMs in similar fashion to the wild type, GEM localization of S3 was severely inhibited. Expression of these mutants in Lck-negative JCaM1 cells showed that although S5 reconstituted activation of nuclear factor NFAT as per the wild type, S3 expression failed to do so. These results suggest that Cys3 of Lck plays a more important role than Cys5 in GEM localization and T cell activation. Additionally, it was found that the degree of T cell function recovery is positively correlated with the degree of Lck expression in GEMs.

Animals↗
PubMed2001

Clinicopathologic study of early-stage mucinous gastric carcinoma.

BACKGROUND: Mucinous gastric carcinoma (MGC) is rare, and whether MGC behaves more aggressively than nonmucinous gastric carcinoma (NGC) is controversial. To the authors' knowledge, there is no study of early-stage MGC, and the pathology and prognosis of patients who have early MGC is unknown. The aim of this study was to clarify the clinicopathologic characteristics of early MGC. METHODS: Pathologic and prognostic data of 30 patients who had early MGC were compared retrospectively against data of 165 patients who had early NGC and 58 patients who had advanced MGC. We defined MGC as a tumor in which more than half of the tumor area contained extracellular mucin pools. We defined early gastric carcinoma as a tumor restricted to the mucosa or to the mucosa and submucosa (T1, International Union Against Cancer [UICC], 1997) regardless of lymph node metastasis. RESULTS: Early MGC tumors, compared with early NGC tumors, were characterized by macroscopic elevation (57% vs. 23%, P < 0.01) and invasion to the submucosa (83% vs. 44%, P < 0.01). Tumor size, frequency of lymph node metastasis, and patient outcome did not differ between the two types, and no patient with early MGC died of recurrence during a median follow-up period of 67 months. When early MGC was compared with advanced MGC, tumor size (2.9 cm vs. 9.4 cm, P < 0.01), frequency of lymph node metastasis (10% vs. 88%,P < 0.01), total gastrectomy (0% vs. 52%, P < 0.01), noncurative surgery (0% vs. 38%, P < 0.01), and recurrent death (0% vs. 57%, P < 0.01) differed significantly. CONCLUSIONS: Our results indicated that although the macroscopic features of early MGC differed from those of early NGC, patient prognosis and the frequency of lymph node metastasis did not differ. Neither did mucinous histology seem to influence outcome adversely after gastrectomy.

Adenocarcinoma, Mucinous↗
PubMed2001

Therapeutic effects of stronger neo-minophagen C at different doses on chronic hepatitis and liver cirrhosis.

Stronger neo-minophagen C (SNMC), a glycyrrhizin (GL) preparation, has been extensively used with considerable success in Japan for the treatment of chronic hepatitis. The aim of the present study was to elucidate the efficacy of administering massive doses of 100 ml/day to patients in whom standard administration (40 ml/day) for 2 weeks did not show sufficient improvement. A comparative study was conducted by dividing at random 100 cases (56.2%), out of a total of 178 enrolled, into two groups, one for the administration of 100 ml/day for 3 weeks (group A) and the other for administration of 40 ml/day for 3 weeks (group B). Cases were rated 'markedly improved'or 'improved' according to their ALT levels (defined respectively as <1.2 times and 1.2-1.5 times the normal upper level 3 weeks after treatment). Except those who dropped out or were otherwise not eligible for analysis, 44 and 46 cases were analyzed. In group A, 23 of 44 cases (52.3%) were rated 'improved' or better whereas only 12 of 46 (26.1%) in group B were 'improved' or better. Group A showed significant improvement compared to group B (P=0.017), thus documenting the greater efficacy of administering SNMC at 100 ml/day compared to only 40 ml/day.

Journal Article↗
PubMed2001

Stent implantation for aortic coarctation complicating the Norwood operation in a 48-day-old baby.

A female infant developed severe aortic coarctation 42 days after a Norwood operation. Balloon dilatation was ineffective due to rapid recoil of the narrowing, but stent implantation completely abolished coarctation. Although the patient died because of low systemic output with high pulmonary flow 62 days after stent implantation, an autopsy showed that the implanted stent was widely patent without any restenosis. Transcatheter stent implantation should be considered for coarctation in selected situations even in early infancy.

Aortic Coarctation↗
PubMed2001

Pathology and prognosis of mucinous gastric carcinoma.

BACKGROUND AND OBJECTIVES: Clinicopathologic characteristics of mucinous gastric carcinoma (MGC) are unclear, and whether surgical results of MGC are unfavorable is controversial. Pathology and prognosis of patients with MGC were studied using multivariate analysis. METHODS: The study included 17 patients with MGC and 614 with nonmucinous gastric carcinoma (NGC). The tumor was defined as MGC when more than one half of tumor area had mucin pools. Patients were evaluated with regard to age, sex, tumor location, size, gross type, depth of wall invasion, lymph node metastasis, lymphatic and vascular permeations, stage of disease, and operative curability. RESULTS: MGC tumors, when compared with NGC tumors, were featured by the large size (9.0 vs. 5.2 cm), grossly infiltrative type (76 vs. 30%), T2 or more invasion (100 vs 53%), positive lymph node metastasis (88 vs. 32%), lymphatic permeation (94 vs. 55%), vascular permeation (47 vs. 25%), and stages III and IV (88 vs. 32%). On a multivariate analysis, mucinous histologic type was not an independent prognostic factor. Although 5-year survival rate for all MGC patients was lower than that for all NGC patients, the survival rate was not different between the MGC and NGC patients when compared in the same category of tumor size, depth of wall invasion, lymph node metastasis, and stage. CONCLUSIONS: MGC is rare and detected mostly in an advanced stage. Mucinous histologic type itself is not a prognostic significance in patients with gastric carcinoma, and the biologic behavior of MGC is similar to that of ordinary advanced gastric carcinoma.

Adenocarcinoma, Mucinous↗
PubMed2001

Thymic carcinoma with tumor thrombus into the superior vena cava.

Tumor thrombus into the vena cava have been reported in cases with renal cell carcinoma, thyroid tumor and in those with thymoma. These tumors are frequently invasive and continuous from the main tumor that shows direct vessel wall invasion. Here, we report a case of thymic carcinoma with superior vena cava syndrome, which was caused by a tumor thrombus in the superior vena cava without vessel wall invasion. The main mediastinal tumor did not show innominate vein invasion, and the superior vena cava syndrome was a result of separate tumor thrombus that was free of vessel wall invasion. The tumor thrombus could be removed through a simple venotomy. To prevent stenosis in the superior vena cava and the left innominate vein, we used a pericardial patch to close the venotomy site.

Carcinoma, Renal Cell↗
PubMed2001

Effect of periodic endoscopy for gastric cancer on early detection and improvement of survival.

BACKGROUND: Increases in the detection of early gastric cancer have indisputably, improved long-term survival. The aim of this study was to establish the value of periodic gastric endoscopy and the appropriate intervals for its performance. METHODS: We compared, retrospectively, the clinicopathologic characteristics and outcomes of two groups of patients who had undergone surgical treatment for gastric cancer. Of a total of 361 patients, 106 had undergone endoscopic examination within 2 years before the detection of gastric cancer (group 1), and 255 had either undergone no endoscopic examination or had had endoscopic examination more than 2 years before the detection of gastric cancer (group 2). For the evaluation of survival rate, the patients in each group were classified into two subgroups: group 1a, endoscopic examination within 1 year before detection; group 1b, endoscopic examination more than 1 year and within 2 years; group 2a, endoscopic examination more than 2 years and within 4 years before detection; and group 2b, endoscopic examination more than 4 years before detection, or no endoscopic examination. RESULTS: Gastric cancer in group 1 was characterized by small tumor size, no tumor invasion beyond the submucosa, few instances of lymphatic and vascular permeation, and few lymph node metastases. The 5-year survival rate for group 1 patients (96.5%) was significantly higher than that for group 2 patients (71.0%; P < 0.01). The survival rates for group 1a patients and group 1b patients were not significantly different (P = 0.4595). The survival rate for patients in group 2a was significantly lower than that for those in group 1a (P < 0.05). CONCLUSION: Periodic gastric endoscopy enables early detection of cancer, thereby improving survival. The optimal interval for periodic examination appears to be 2 years.

Aged↗