Biomedical subjects

E Kyo

Publications and source records attributed to E Kyo.

At least 19 recordsLinked to original sources

PubMed2001

Initial and long-term results of directional coronary atherectomy in unprotected left main coronary artery.

Angioplasty in the unprotected left main coronary artery (LMCA) has been controversial. Recently, several studies have suggested that new procedures and devices such as directional coronary atherectomy (DCA) and stents may change this situation. Although there are many reports of unprotected LMCA stenting, there are few reports of DCA of this lesion. Therefore, initial and long-term results were evaluated in 101 patients who underwent DCA for unprotected LMCA in our hospital. Emergency procedures were performed in 15 patients and electively in 86 patients. Scheduled angiographic follow-up was routinely performed, and all patients were clinically followed for >4 months after DCA. Technical success was achieved in 99%, and in-hospital outcomes were cardiac death (2%), noncardiac death (4%), Q-wave myocardial infarction (1%), non-Q-wave myocardial infarction (8.9%), coronary artery bypass grafting (0%), and repeat angioplasty (4%). In-hospital results varied considerably, depending on presentation. In-hospital mortality was significantly higher in the emergency, left ventricular ejection fraction < or =35%, and high-risk surgical subgroups. The angiographic restenosis rate was 20.4% at follow-up, and its predictor was postminimal lumen diameter by multivariate analysis. Mean clinical follow-up was 2.8 years; estimated 1- and 3-year survival rates were 87% and 80.7%, respectively. The cardiac survival rate of the low-risk surgical subgroup was significantly higher than that of the high-risk surgical subgroup (p <0.05). Thus, our data show that DCA can be performed safely and effectively in unprotected LMCA with an acceptable low restenosis rate and high survival rate.

Adult↗

PubMed2001

Immunomodulatory effects of aged garlic extract.

Using various kinds of models, we examined the effects of aged garlic extract (AGE) on immune functions. In the immunoglobulin (Ig)E-mediated allergic mouse model, AGE significantly decreased the antigen-specific ear swelling induced by picryl chloride ointment to the ear and intravenous administration of antitrinitrophenyl antibody. In the transplanted carcinoma cell model, AGE significantly inhibited the growth of Sarcoma-180 (allogenic) and LL/2 lung carcinoma (syngenic) cells transplanted into mice. Concomitantly, increases in natural killer (NK) and killer activities of spleen cells were observed in Sarcoma-180--bearing mice administered AGE. In the psychological stress model, AGE significantly prevented the decrease in spleen weight and restored the reduction of anti-SRBC hemolytic plaque-forming cells caused by the electrical stress. These studies strongly suggest that AGE could be a promising candidate as an immune modifier, which maintains the homeostasis of immune functions; further studies are warranted to determine when it is most beneficial.

Adjuvants, Immunologic↗

PubMed2001

Pharmacologic activities of aged garlic extract in comparison with other garlic preparations.

We investigated the pharmacologic activities of four garlic preparations, raw garlic juice (RGJ), heated garlic juice (HGJ), dehydrated garlic powder (DGP) and aged garlic extract (AGE). The study used three animal models, i.e., testicular hypogonadism (hypospermatogensis and impotence) induced by warm water treatment, intoxication of acetaldehyde and growth of inoculated tumor cells. RGJ was found to be effective only in recovery of testicular function. The efficacy of HGJ was observed in three models; however, it did not improve impotence. DGP was effective in recovery of spermatogenesis and stimulated acetaldehyde detoxification. Significant beneficial effects of AGE were found in all three models. Although all four garlic preparations significantly enhanced natural killer (NK) and killer cell activities of the spleen cells of tumor-bearing mice, only AGE and HGJ inhibited the growth of inoculated tumor cells. These results suggest that different types of garlic preparations have different pharmacologic properties, and among the four garlic preparations studied, AGE could be the most useful garlic preparation.

Acetaldehyde↗

PubMed2001

[Role of new devices for angioplasty in the unprotected left main coronary artery].

OBJECTIVES: Angioplasty for the unprotected left main trunk remains controversial, but new procedures and devices such as directional coronary atherectomy and stenting have improved the results. We compared the results of angioplasty with the inflexible balloon and new devices. METHODS: The procedures were performed in 239 consecutive lesions in 160 patients between April 1986 and March 2000. This study excluded emergency cases and repeat angioplasty cases, and included 120 initial and elective cases. Initial and long-term results were compared between the balloon group (n = 29) and the new device group (n = 91). RESULTS: Lesion success rate was lower in the balloon group (90% vs 100%, p < 0.05), but there were no significant differences in in-hospital results including cardiac death (0% vs 0%), noncardiac death (0% vs 3.3%), Q-wave myocardial infarction (0% vs 2.2%), non-Q wave myocardial infarction (3.4% vs 6.6%), bypass surgery (0% vs 0%) and repeat angioplasty (6.9% vs 1.1%). Quantitative angiography showed significant improvements in minimal lumen diameter (mean 2.17 vs 3.16 mm, p < 0.001) and percentage diameter stenosis (mean 31% vs 13%, p < 0.001) in the new device group after the procedures. The minimum lumen diameter remained larger at 3 (p < 0.001) and 6 months (p < 0.05) in the new device group. Therefore, angiographic restenosis rate was higher in the balloon group (55% vs 21%, p < 0.005). Five-year survival rate showed no significant difference between the groups (75.0% vs 83.8%). CONCLUSIONS: New devices significantly improved the minimal lumen diameter after angioplasty for unprotected left main trunk disease, and lead to significant improvement of restenosis rate at follow-up.

Aged↗

PubMed2000

Initial and 6-month results of biodegradable poly-l-lactic acid coronary stents in humans.

BACKGROUND: Although metallic stents are effective in preventing acute occlusion and reducing late restenosis after coronary angioplasty, many concerns still remain. Compared with metallic stents, poly-l-lactic acid (PLLA) stents are biodegradable and can deliver drugs locally. The aim of this study was to evaluate the feasibility, safety, and efficacy of the PLLA stent. METHODS AND RESULTS: Fifteen patients electively underwent PLLA Igaki-Tamai stent implantation for coronary artery stenoses. The Igaki-Tamai stent is made of a PLLA monopolymer, has a thickness of 0.17 mm, and has a zigzag helical coil pattern. A balloon-expandable covered sheath system was used, and the stent expanded by itself to its original size with an adequate temperature. A total of 25 stents were successfully implanted in 19 lesions in 15 patients, and angiographic success was achieved in all procedures. No stent thrombosis and no major cardiac event occurred within 30 days. Coronary angiography and intravascular ultrasound were serially performed 1 day, 3 months, and 6 months after the procedure. Angiographically, both the restenosis rate and target lesion revascularization rate per lesion were 10.5%; the rates per patient were 6.7% at 6 months. Intravascular ultrasound findings revealed no significant stent recoil at 1 day, and they revealed stent expansion at follow-up. No major cardiac event, except for repeat angioplasty, developed within 6 months. CONCLUSIONS: Our preliminary experience suggests that coronary PLLA biodegradable stents are feasible, safe, and effective in humans. Long-term follow-up with more patients will be required to validate the long-term efficacy of PLLA stents.

Adult↗

PubMed2000

Angiographic and clinical outcome of a new self-expanding intracoronary stent (RADIUS): results from multicenter experience in Japan.

The RADIUS coronary stent featuring a multisegmented slotted tube design and self-expanding nitinol delivery system has a high radial force and flexibility, uniform expansion, and contours to the shape of the vessel. Successful stent deployment was achieved in 104 stable angina patients (106 lesions; 44% LAD, 19% circumflex, and 37% RCA). Mean minimal lumen diameter (MLD) increased from 0.77 +/- 0.46 mm to 2.88 +/- 0.61 mm and mean percent diameter stenosis (% DS) decreased from 73 +/- 14% to 6 +/- 13% immediately after the procedure. At 6-month follow-up, two patients (2%) underwent urgent target revascularization, and cerebral bleeding occurred in one patient (1%). Angiographic follow-up was performed in 94 lesions (89%) and mean MLD and mean % DS were 2.08 +/- 0.92 mm and 30% +/- 24%, respectively. Stent restenosis (>50% diameter stenosis at follow-up) was observed in 16 (17%) of all lesions. The high success rate for stent deployment, low incidence of major adverse cardiac event, and lower restenosis rate after stent implantation indicate that the RADIUS stent is useful for coronary intervention.

Adult↗

PubMed2000

[Predictors of prognosis after angioplasty in the unprotected left main coronary artery].

OBJECTIVES: The short-term and long-term predictors of outcome after coronary angioplasty in the unprotected left main coronary artery were investigated. METHODS: The procedure was performed in 122 consecutive patients for de novo lesions without myocardial infarction in our hospital between April 1986 and October 1998, including 16 emergency cases. Procedures were directional coronary atherectomy (73 patients), balloon angioplasty (31 patients), and stent implantation (18 patients). There were 101 males and mean age was 68 +/- 10 years. Follow-up angiography was performed in 98% of discharged patients, and all patients were clinically followed up for more than 1 year. Clinical and angiographic predictors of in-hospital and long-term outcome were evaluated. RESULTS: The in-hospital mortality was 5.7% (7 of 122 patients). Multivariate analysis revealed that more patients were admitted as emergency cases (57% vs 10%, p = 0.0088), with left ventricular ejection fraction < or = 35% (57% vs 22%, p = 0.029) and renal failure (43% vs 3%, p = 0.0004) finally died. Mean follow-up period was 3.5 years. Estimated survival rate was 77.1%, and cardiac-death free survival rate was 81.0% at 5 years by the Kaplan-Meier method. Univariate analysis showed that the predictors of cardiac death were emergency angioplasty, renal failure, decreased left ventricular ejection fraction, multivessel disease and unstable angina and/or congestive heart failure. Cox's regression model showed that renal failure (p = 0.0004) and multivessel disease (p = 0.0075) were significant predictors of long-term prognosis. CONCLUSIONS: Renal failure was the strongest predictor of outcome after unprotected left main coronary artery angioplasty.

Aged↗

PubMed1999

Prevention of psychological stress-induced immune suppression by aged garlic extract.

We determined the effect of Aged Garlic Extract (AGE) on damage caused to immune function by a psychological stress using a communication box. After four days of a psychological stress, a decrease in spleen weight and spleen cells was observed in the psychological stress-exposed mice as compared normal mice (non-stress). AGE significantly prevented the decreases in spleen weight and cells. Additionally, AGE significantly prevented the reduction of hemolytic plaque-forming-cells in spleen cells and anti-SRBC antibody titer in serum caused by this psychological stress. Moreover, a reduction in NK activities was observed in the psychological stress-exposed mice as compared with normal mice (non-stress), whereas NK activities in the AGE administered mice were almost the same as normal mice (non-stress). These results indicate that psychological stress qualitatively and quantitatively impairs immune function, and that AGE is extremely useful for preventing psychologically-induced damage.

Animals↗

PubMed1993

Interleukin 1 alpha acts as an autocrine growth stimulator for human gastric carcinoma cells.

The expression and effect of interleukin 1 alpha (IL-1 alpha) were examined in human gastric carcinoma cell lines to determine if IL-1 alpha acts as a growth stimulator for these cells. Six of 8 gastric carcinoma cell lines expressed IL-1 alpha mRNA at various levels. Among them, TMK-1 and MKN-7 cells secreted IL-1 alpha into the culture fluid, in an especially large amount by MKN-7 cells. Scatchard plot analysis of IL-1 alpha binding revealed that TMK-1 cells had only one type of high-affinity receptors, whereas MKN-7 cells had high- and low-affinity receptors. Cell growth and DNA synthesis of TMK-1 and MKN-7 cells were stimulated by IL-1 alpha, and those of MKN-7 were inhibited by addition of anti-IL-1 alpha antibody or IL-1 receptor antagonist. The expression of IL-1 alpha mRNA by these cell lines was induced by either IL-1 alpha, epidermal growth factor, or transforming growth factor alpha. On the other hand, IL-1 alpha increased the mRNA expression for transforming growth factor alpha and epidermal growth factor receptor. These findings indicate that IL-1 alpha is an autocrine growth stimulator for gastric carcinoma cells and the interaction with epidermal growth factor/transforming growth factor alpha/receptor system should be involved in the growth modulation by IL-1 alpha.

Cell Division↗

PubMed1993

GC factor represses transcription of several growth factor/receptor genes and causes growth inhibition of human gastric carcinoma cell lines.

The GC factor (GCF) binds to specific GC-rich sequences in the epidermal growth factor receptor (EGFR) gene promoter and represses its transcription. In this study, by the use of GCF transfection, we examined whether GCF represses the gene expression of several other growth factors and receptors and causes growth inhibition of cancer cells. The transfection of GCF expression vector into gastric carcinoma cell lines (TMK-1 and MKN-28) decreased the mRNA levels of transforming growth factor (TGF) alpha, insulin-like growth factor II, and c-met. The reduction of TGF-alpha expression was confirmed at the protein level by enzyme-linked immunosorbent assay. Transfection of GCF expression vector interfered with the mRNA accumulation for EGFR and TGF-beta induced by epidermal growth factor in gastric carcinoma cell lines. The carcinoma cells transfected with GCF expression vector did not grow in a serum-free medium, whereas the control cells did grow under serum-free conditions. When the growth of the gastric carcinoma cell lines was studied in nude mice, GCF-transfected carcinoma cells showed a significantly slower growth compared to the control tumor. Transient cotransfection analysis with NIH3T3 cells revealed that GCF repressed the promoter activity of TGF-alpha in addition to EGFR. These findings indicate that GCF negatively regulates gene expression of not only the EGFR but also several other growth factor and receptor genes and can inhibit the growth of gastric carcinomas in immunodeficient mice.

Animals↗

PubMed1992

A monoclonal antibody capable of detecting new differentiation antigen of the stomach.

A monoclonal antibody (MAb) was raised against a gastric adenocarcinoma cell line TMK-1 that shows parietal cell differentiation. This MAb, an IgMK, named 20DII, reacted immunohistochemically with the intracytoplasmic secretory canalicular membranes of normal parietal cells of the stomach. In the fetal stomach at 4 months of gestation, the luminal surface of fundic epithelia and developing parietal cells had MAb20DII immunoreactivity, but at 6 months of gestation only parietal cells showed immunoreaction. Out of 133 gastric carcinomas, 98 (74%) had MAb20DII immunoreactivity. In the well-differentiated type, immunoreactivity was localized at the luminal surface of tumor cells and, in the poorly differentiated type, in the intracytoplasmic tubulovesicles of tumor cells. In Western-blot analysis, the antigenic molecule had a molecular weight exceeding 300 kDa in the tumor tissues, but only a 62-kDa immunoblot band was seen in the corresponding non-cancerous gastric mucosa. However, there was no correlation between the expression of high-molecular-weight antigens and the histological types of gastric carcinoma. These results suggest that 20DII antigen may be involved in differentiation of parietal cells in the fetal stomach and in stomach cancer.

Adenocarcinoma↗

PubMed1992

Growth inhibition of transforming growth factor beta on human gastric carcinoma cells: receptor and postreceptor signaling.

The effect of transforming growth factor beta (TGF-beta) on human gastric carcinoma cell lines was examined. Cell growth and DNA synthesis of TMK-1 were inhibited by TGF-beta, whereas MKN-28 presented no response to TGF-beta. Scatchard plot analysis of TGF-beta binding showed that TMK-1 had a relatively small number of high-affinity receptors, whereas MKN-28 had a large number of low-affinity receptors. By affinity labeling, only the type I receptor (Mr 65,000) for TGF-beta was detected in TMK-1, while three types of receptors, type I, type II (Mr 85,000-95,000), and type III (Mr 250,000-350,000), for TGF-beta were present in MKN-28. TGF-beta treatment reduced p34cdc-2 kinase activity and the level of phosphorylation of retinoblastoma protein in TMK-1, whereas it did not affect them in MKN-28. mRNAs for MYC and platelet-derived growth factor B chain were increased by treatment of TGF-beta on TMK-1. cAMP-responsive element binding activity was decreased by TGF-beta treatment in MKN-28 but not in TMK-1. This was closely correlated with protein kinase C activity. These results suggest that the type I receptor for TGF-beta in human gastric carcinoma cells may be mainly linked with the growth inhibition of TGF-beta by a decrease in retinoblastoma protein phosphorylation by p34cdc-2 without suppression of MYC expression. Conversely, TGF-beta may reduce protein kinase C activity and cAMP-responsive element binding activity in TGF-beta-resistant gastric carcinoma cells.

CDC2 Protein Kinase↗

PubMed1992

Systemic atrioventricular valve replacement in an infant with corrected transposition of the great arteries.

A 3-month-old infant with corrected transposition of the great arteries and severe systemic atrioventricular valve regurgitation due to "Ebstein-like anomaly" is reported. Through a right thoracotomy and longitudinal left atrial incision, a 19-mm St. Jude Medical valve was implanted into the annulus without removing the native valve. He is doing well 7 months after operation.

Ebstein Anomaly↗

PubMed1991

Effects of tyrosine kinase inhibitor, erbstatin, on cell growth and growth-factor/receptor gene expression in human gastric carcinoma cells.

The effect of tyrosine kinase inhibitor, erbstatin, on cell growth and mRNA expression of growth-factor/receptor system was examined in 6 human gastric-carcinoma cell lines. Erbstatin inhibited both EGF-induced and serum-stimulated cell growth of all 6 cell lines (TMK-1, MKN-1, -7, -28, -45, -74) in a dose-dependent manner. 3H-thymidine incorporation by TMK-1 cells was also suppressed by erbstatin. Erbstatin inhibited protein kinase activity of EGF receptor, p185ERBB2 and pp60c-src in TMK-1 cells. The expression of mRNA of EGF receptor gene and ERBB-2 by TMK-1 cells was not changed by erbstatin treatment, whereas that of c-src was slightly decreased. Interestingly, erbstatin decreased membrane-bound TGF-alpha precursor as measured by anti-TGF-alpha antibody-binding assay, although mRNA expression for TGF-alpha was not altered by erbstatin. Our findings suggest that erbstatin may act as a growth inhibitor for human gastric-carcinoma cells and may not only inhibit tyrosine kinase activities but also negatively modulate the post-transcriptional step of TGF-alpha expression.

Cell Division↗

PubMed1991

Inhibition of 3H-TdR uptake for human gastric carcinoma cells by epidermal growth factor specific antibody.

This study examined whether human gastric carcinoma cells produced EGF for self-stimulation, using TMK-1 and MKN-28 cells which express mRNA for EGF and EGF receptor. EGF protein production was confirmed by ELISA and flow cytometric analysis. The lysates of these cells replaced EGF-induced biological activity to EGF receptor bearing KB cells but the culture supernatants did not. Furthermore, EGF-radioreceptor assay revealed non-secretion of EGF product. EGF specific monoclonal antibody neutralized exogenous EGF-induced 3H-TdR uptake, and inhibited spontaneous 3H-TdR uptake of TMK-1 and MKN-28 cells. These results suggest that EGF specific antibody binds to EGF protein at the cell surface, leading to the inhibition of 3H-TdR uptake, and that EGF produced by tumor cells may act as an autocrine growth factor in human gastric carcinoma cells.

Antibodies, Monoclonal↗

PubMed1990

EGF and TGF-alpha, the ligands of hyperproduced EGFR in human esophageal carcinoma cells, act as autocrine growth factors.

In order to ascertain autocrine growth factors in esophageal carcinomas, we analysed expression of mRNAs and proteins for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) in 6 esophageal carcinoma cell lines. Gene alterations were also examined. All of the esophageal carcinoma cell lines expressed mRNA for EGFR and TGF-alpha genes. Interestingly, EGF mRNA of about 5.0 kb was also detected in TE-1, TE-2, and TE-8 cells. Production of protein was also confirmed by binding assay and ELISA on 3 of the 6 cell lines. The cells had a relatively high number of EGFRs and produced TGF-alpha and EGF protein at the same time. Furthermore, anti-EGF (KEM-10) and anti-TGF-alpha (WA-3) monoclonal antibodies (MAbs) inhibited spontaneous uptake of tritiated thymidine (3H-TdR) by TE-1 cells which expressed EGF, TGF-alpha and EGFR mRNA and protein. These results strongly suggest that EGF and/or TGF-alpha produced by carcinoma cells function as autocrine growth factors for human esophageal carcinomas.

Adenocarcinoma↗

PubMed1990

Expression of several growth factors and their receptor genes in human colon carcinomas.

We have examined the expression of mRNAs for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), EGF receptor (EGFR), PDGF-A chain (PDGFA), PDGF-B chain (PDGFB) and PDGF receptor (PDGFR) genes in seven human colorectal carcinoma cell lines and 18 human colorectal carcinomas. In surgically resected specimens of the 18 colorectal tumors, TGF-alpha, EGFR, PDGFA, PDGFB and PDGFR mRNAs were detected at various levels in 15 (83%), 9 (50%), 18 (100%), 8 (44%) and 12 (67%), respectively. They were also detected in normal tissues. Interestingly, EGF mRNA was detected in only five (28%) of the tumors, but not in normal mucosa. Expression of EGF was also confirmed immunohistochemically in tumor cells. Of the five tumors expressing EGF, four expressed EGFR mRNA and showed a tendency to invade veins and lymphatics. All the colorectal carcinoma cell lines expressed TGF-alpha mRNA, and five cell lines expressed EGFR mRNA simultaneously. Production of TGF-alpha protein by DLD-1 and CoLo320DM cells was confirmed by TGF-alpha specific monoclonal antibody binding assay. The spontaneous 3H-thymidine uptake by DLD-1 was suppressed by an anti-TGF-alpha monoclonal antibody. PDGFA and PDGFB mRNA were also expressed in four cell lines, but PDGFR and EGF mRNA was not detected. These results suggest that human colorectal carcinomas express multi-loops of growth factors and that TGF-alpha produced by tumor cells functions as an autocrine growth factor in human colonic carcinoma.

Antibodies, Monoclonal↗

PubMed1990

Expression of epidermal growth factor, transforming growth factor-alpha and their receptor genes in human gastric carcinomas; implication for autocrine growth.

The expressions of mRNA for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha) and EGF receptor (EGFR) genes were examined in 7 human gastric carcinoma cell lines and 15 gastric carcinoma tissues and the corresponding normal mucosas. All of the gastric carcinoma cell lines expressed mRNA for EGFR and TGF-alpha genes. TMK-1 and MKN-28 cells also expressed EGF mRNA. Production of EGF, TGF-alpha and EGFR protein by gastric carcinoma cell lines was also confirmed by EGF and TGF-alpha specific monoclonal antibody binding. As for surgical specimens, EGFR and TGF-alpha mRNA were detected at high levels in all the tumor tissues. Interestingly, EGF mRNA was detected in 5 (33.3%) of the 15 gastric carcinomas but it was not detected in normal tissues. Moreover, anti-EGF and anti-TGF-alpha monoclonal antibodies inhibited the spontaneous 3H-TdR uptake by gastric carcinoma cells. These results suggest that EGF and/or TGF-alpha produced by tumor cells act as autocrine growth factors for gastric carcinomas.

Antibodies, Monoclonal↗