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Yutaka Shimada

Publications and source records attributed to Yutaka Shimada.

At least 91 records · Page 5Linked to original sources
PubMed2003

Validation of intra-operative detection of paratracheal lymph node metastasis using real-time RT-PCR targeting esophageal squamous cell carcinoma.

BACKGROUND: We previously reported that there was a significant correlation between paratracheal lymph node (LN) metastasis and cervical LN metastasis in thoracic esophageal squamous cell carcinoma (ESCC) patients. The purpose of this study was to establish an intra-operative detection method of LN micrometastasis (MM) of ESCC using hematoxylin-eosin (HE) staining, immunohistochemistry (IHC) and real-time RT-PCR with a Light Cycler technique, and to evaluate which method, or combination of methods, is most suitable for intra-operative detection of paratracheal LN MM. METHODS: Under informed consent, we obtained 33 dissected paratracheal LN samples from 22 operative patients with ESCC. Afterwards, one LN was separated into three parts by a sharp razor, and each part was checked for metastasis by HE staining, IHC with anti-cytokeratin antibody and real-time RT-PCR for SCC mRNA with a Light Cycler. RESULTS: It took 3 h for detection by real-time RT-PCR, while it took 2 h by IHC. The detection rates of MM by HE staining, IHC and real-time RT-PCR were 50.0, 33.3 and 83.3%, respectively. However, there was a case of false negative detection that was not detected by IHC or PCR. CONCLUSION: The real-time RT-PCR method was useful for intra-operative detection of paratracheal LN metastasis. However, combination analysis of HE staining, IHC and real-time RT-PCR may be desirable because there was a case of false negative detection by IHC and real-time RT-PCR.

Carcinoma, Squamous Cell↗
PubMed2003

Expression and function of the calcium-sensing receptor in pancreatic islets and insulinoma cells.

INTRODUCTION: We previously demonstrated that human insulinoma cells express the calcium-sensing receptor (CaR). AIM: To investigate the expression of CaR in the human pancreas and to evaluate the differences in responses of human insulinoma cells and normal rat islets to extracellular calcium2+ [Ca2+]o. METHODOLOGY: To evaluate CaR expression in the normal human pancreas, immunohistochemical and reverse transcription polymerase chain reaction studies were performed. To evaluate the response of normal islets and insulinoma cells to changes in the [Ca2+]o concentration, cytosolic free calcium levels were measured by microfluorometry. Because it is difficult to obtain viable normal human islets, we used normal rat islets instead. RESULTS: CaR is expressed in both human pancreatic islets and human insulinoma cells. Microfluorometry showed an increase in the [Ca2+]i level in response to changes in the [Ca2+]o concentration, with a more sensitive response in human insulinoma cells than in normal islets. When 1 micromol/L wortmannin (a selective phosphatidylinositol 3-kinase inhibitor) was added to the perfusion medium, the response disappeared in insulinoma cells but not in islets. CONCLUSION: Both insulinoma cells and islets expressed CaR; however, the reactivity to changes in the [Ca2+]o concentration was different between them. These findings suggest that the signaling pathways controlling the changes in [Ca2+]i differ between normal rat islets and human insulinoma cells.

Animals↗
PubMed2003

Reexamination of the relation between menstrual cycle and kampo diagnosis, yin-yang.

Several Chinese herbal medicine textbooks describe that a short menstrual cycle indicates "yang" status and a long cycle indicates "yin" status. However, we sometimes encounter yang patients with a long cycle or yin patients with a short cycle in daily practice. Therefore, we reviewed the relationship between yin-yang and length of menstrual cycle. A questionnaire addressing both menstrual cycle and several parameters for determining yin-yang was completed at the time of the patients' visit to the hospital. Patients were divided into yang or yin groups, and menstrual cycle was compared between the two groups. A short menstrual cycle was mostly observed in yin patients (27.42 +/- 1.73, 95% CI: 26.32-28.52, n = 12) and a long cycle was mostly observed in yang patients (31.63 +/- 3.96, 95% C.I: 29.51-33.74, n = 16). The difference in menstrual cycle between the two groups was significant (p = 0.002), and this result was entirely opposite to the traditional theory. This study identified a discrepancy between the traditional theory and the actual menstrual cycle findings in this small population. Current reexamination of the relationship between yin-yang and menstruation in a larger population is warranted.

Adult↗
PubMed2003

Choto-san prevents occurrence of stroke and prolongs life span in stroke-prone spontaneously hypertensive rats.

The effects of long-term oral administration of choto-san (diao-teng-san in Chinese) extract on the occurrence of stroke and life span were investigated in stroke-prone spontaneously hypertensive rats (SHR-SPs). Twenty-four rats were ramdomized into three groups. From 8 weeks of age, 0.1% and 0.3% choto-san groups were given water containing 0.1% (150 mg/kg/day) and 0.3% (450 mg/kg/day) choto-san extract, respectively. A control group was given only water. The mean survival times of the control group, 0.1% and 0.3% choto-san groups were 122.1, 159.8 and 176.8 days, respectively. The percent survivals of both the 0.1% and 0.3% choto-san groups were significantly enhanced compared to the control (Kaplan-Meier analysis followed by log-rank test; 0.1% choto-san: p < 0.05; 0.3% choto-san: p < 0.05). Furthermore, the cumulative percent occurrence of neurological and behavioral signs accompying stroke in the 0.3% choto-san group was significantly inhibited compared to the control (p < 0.05). These results suggested that choto-san prevents the occurrence of stroke and prolongs the life span of SHR-SPs.

Animals↗
PubMed2003

Clinical evaluation of the effect of daio (rhei rhizoma) on the progression of diabetic nephropathy with overt proteinuria.

We studied the effect of traditional herbal medicines containing daio (Rhei Rhizoma) on the long-term progression of diabetic nephropathy with overt proteinuria in eight patients [mean age 60 (45-73) years; duration of diabetes 18 (7-36) years]. At the beginning of the study, mean HbA1c was 8.2% and mean serum creatinine was 1.0 +/- 0.3 mg/dl. Everypatient had diabetic neuropathy and retinopathy. Three of the patients had hypertension and four had ischemic heart disease. After 107 +/- 25 months, the mean serum creatinine level had significantly increased to 4.8 +/- 2.6 mg/dl. The mean serum creatinine levels of five patients not advancing to dialysis treatment increased from 1.2 +/- 0.3 to 3.2 +/- 1.0 mg/dl, and the three patients requiring dialysis increased from 0.8 +/- 0.1 to 7.5 +/- 2.1 mg/dl. In the control group, treated without traditional herbal medicines, the mean serum creatinine level had significantly increased from 1.0 +/- 0.3 to 9.5 +/- 1.9 mg/dl after 71 +/- 12 months. All of the control group required dialysis treatment. Diabetic nephropathy with overt proteinuria is reported to develop into renal failure after 6-7 years. In this retrospective study, traditional herbal medicines with Daio were considered to be effective in prolonging the pre-dialysis period of diabetic nephropathy.

Aged↗
PubMed2003

Challenge tests and kampo medicines: case report and review of the literature.

In order to diagnose Kampo medicine-induced liver injury, a challenge test using the suspected medicine is the most reliable method of assessing the relationship between Kampo medication and liver injury. However, such a challenge test may cause severe liver injury. We examined the clinical features and safety of challenge tests conducted by a physician in a case of Kampo medicine-induced liver injury that we encountered as well as in the previous literature (six cases) in Japan. In all cases except two, one-third of the daily dose was given a few times for the challenge test (challenge dose was not described in two cases). The reaction induced by the challenge peaked 1-3 days after challenge. Mild eosinophilia (6%) was observed in two cases. All liver injuries induced by challenge cleared within 2 weeks, and neither severe nor fatal liver injury was observed. In conclusion, a challenge with a small dose of Kampo medicine conducted in our case and in the previous literature induced mild and reversible liver injury. The safety and availability of challenge with a small dose of Kampo medicine should be further examined in a larger population with Kampo medicine-induced liver injury.

Chemical and Drug Induced Liver Injury↗
PubMed2003

Effects of curcuma drugs on vasomotion in isolated rat aorta.

The effectiveness of Curcuma drugs against "Oketsu" and the differences in their efficacy were evaluated by examining their vasomotional effects as one index. Since nitric oxide (NO) is the relaxation factor of vascular smooth muscle and also an inhibitor of platelet aggregation in blood vessels, substances showing NO-dependent relaxation are thought to be effective in improving Oketsu. In this study, five Curcuma drugs derived from Curcuma longa, C. kwangsiensis, C. phaeocaulis, C. wenyujin, and C. zedoaria were used. Methanol extracts exhibited intense effects on relaxation in rings precontracted by prostaglandin F(2alpha) (PGF(2alpha)) despite pretreatment with and without N(G)-nitro-l-arginine methyl ester (L-NAME) as an inhibitor of NO synthesis. The maximal activities were approximately 80% at 10(-3) g/ml. From these methanol extracts, curcumin and eight sesquiterpenes were isolated. Since all these compounds showed NO-independent relaxation effects with almost the same intensities, the relaxation effects of Curcuma drugs can be estimated by the total amounts of curcumin and sesquiterpenes. Polysaccharides, the main constituents of methanol-insoluble compounds of water extracts, in contrast, showed contraction effects; only polysaccharides in C. zedoaria showed NO-dependent relaxation as well as contraction. All water extracts showed relaxation effects as sum of the methanol-soluble compounds-induced relaxation and polysaccharides-induced contraction. Therefore, all Curcuma drugs tested in the present study can be effective for vasodilation. Moreover, the drug derived from C. zedoaria has potential to cure Oketsu with its various acting points.

Animals↗
PubMed2003

Cell culture in esophageal squamous cell carcinoma and the association with molecular markers.

PURPOSE: We reported previously that the patients in whom cancer cells could be cultured as continuous cell lines had a poor prognosis of esophageal squamous cell carcinoma (ESCC) patients. In this study, to evaluate additional evidence of prognostic significance and the genetic background of cell culture, we analyzed 203 ESCC patients. EXPERIMENTAL DESIGN: Culture samples were obtained from resected 203 primary ESCC (from 1986 to 1998; R0 resection). The expression of six molecular markers was evaluated retrospectively in resected primary esophageal tumors by immunohistochemical analysis, and the capability of establishing cell lines was compared. RESULTS: Thirty-five cell lines (17.2%) were established from 203 ESCC patients: group 1 (n = 35), from whom cancer cells could be cultured as continuous cell lines, and group 2 (n = 168), from whom cell lines could not be established. The cumulative survival rate of patients in group 1 was significantly lower than that of those in group 2 (P = 0.0006). Cox's proportional hazard model revealed that cell culture capability was an independent prognostic factor (risk ratio, 1.98; P = 0.007). Univariate logistic regression analysis revealed that cell culture capability had associations with the following molecular biological factors: cyclin D1, p53, murine double minute 2, p27, and fragile histidine triad gene (P < 0.05). However, multivariate logistic regression analysis revealed that p53 protein accumulation and MDM2 protein expression predict establishment of cell line in ESCC (odds ratio, 7.72 and 8.62, respectively). CONCLUSIONS: Cell culture capability is a significant prognostic factor in ESCC. p53 and MDM2 may have a crucial role in the establishment of ESCC cell lines.

Aged↗
PubMed2002

Expression of cyclooxygenase-2 in primary and remnant gastric carcinoma: comparing it with p53 accumulation, Helicobacter pylori infection, and vascular endothelial growth factor expression.

BACKGROUND AND OBJECTIVES: Cyclooxygenase-2 (COX-2) expression may contribute to the synthesis of prostanoids, which have been related to carcinogenesis and tumor progression. It is well known that the gastric remnant is at greater risk of the development of gastric cancer than is the whole stomach; incidence rates for gastric cardia adenocarcinoma are rising in the United States and Europe. Our objective was to determine the involvement of COX-2 in primary and remnant gastric cancer tissues as well as in adjacent noncancerous mucosa. METHODS: We investigated the expression of COX-2 in 91 human gastric cancer tissue and adjacent noncancerous mucosa samples (40 remnant gastric cancer, 37 gastric cardia cancer, and 14 gastric corpus and antrum cancer), using immunohistochemistry. In addition, p53 expression, Helicobacter pylori infection, and vascular endothelial growth factor in the tissues were evaluated by immunohistochemical staining and compared with COX-2 expression. RESULTS: There were no significant differences in clinicopathological data in the gastric cancer tissues. There was a significant relation between the expression of COX-2 and p53 in gastric cancer tissues (P = 0.0048). However, vascular endothelial growth factor expression and Helicobacter pylori infection showed no correlation with the expression of COX-2. In the case of adjacent noncancerous mucosa, the positive rate of COX-2 expression was significantly higher in the remnant gastric cancers (75.0%) than in the primary gastric cancers (25.5%) (P < 0.0001). CONCLUSIONS: This information may help in the analysis of the carcinogenesis of gastric cancer; there is also a possibility that the COX-2 selective inhibitor to the remnant gastric cancer has a chemopreventive effect.

Adult↗
PubMed2002

Inhibitory effects of Keishi-bukuryo-gan on free radical induced lysis of rat red blood cells.

Keishi-bukuryo-gan (KBG) prevents the progression of atherosclerosis in cholesterol-fed rabbits by its antioxidative effect. The present study was to test our hypothesis that ingestion of KBG would protect red blood cell (RBC) membranes from free radical induced oxidation if polyphenolic antioxidants in KBG could be absorbed and circulated in the blood. When incubated with a RBC suspension, KBG and four of five herb medicines constituting KBG provided strong protection for RBC membranes against haemolysis induced by 2,2-azo-bis (2-amidinopropane) dihydrochloride (AAPH), an azo free radical initiator. The inhibitory effect was dose dependent at concentrations of 100-1000 microg/mL. Furthermore, the ingestion of 200 mg of KBG was associated with a significant decrease in susceptibility of RBC to haemolysis in rats.

Amidines↗
PubMed2002

Keishi-bukuryo-gan preserves the endothelium dependent relaxation of thoracic aorta in cholesterol-fed rabbit by limiting superoxide generation.

Formerly, we have reported that keishi-bukuryo-gan prevents the progression of atherosclerosis in cholesterol-fed rabbits and inhibits the free radical-induced RBC haemolysis in rats. The present study was performed to investigate how keishi-bukuryo-gan (KBG) inhibits the early stage of atherosclerosis. Plasma lipid concentration and hydroxyl radical generation during respiratory burst in neutrophils were evaluated at the start and end of the study. The protective effect of KBG against endothelium disorder due to hypercholesterolaemia was examined. Twelve male Japanese white rabbits (2 kg body weight) were divided into two groups. Group A (n = 6) was fed standard rabbit chow containing 1% cholesterol for 4 weeks. Group B (n = 6) was fed standard rabbit chow containing 1% cholesterol and 1% KBG for 4 weeks. In the plasma lipid concentration, only the lipid peroxide concentration of group A was significantly higher than that of group B. At the end of the study, DMPO-OH, the spin-trapped adduct of hydroxyl radicals generated by neutrophils, was increased in both groups, and this increase was marked in group B. Endothelium-dependent vasodilatation by acetylcholine increased significantly in group B compared with group A. Thus, KBG protects the vascular endothelium function by its antioxidative effect and by inhibiting the release of free radicals from neutrophils in vivo.

Acetylcholine↗
PubMed2002

MYEOV, a gene at 11q13, is coamplified with CCND1, but epigenetically inactivated in a subset of esophageal squamous cell carcinomas.

DNA amplifications at 11q13 are frequently observed in esophageal squamous cell carcinoma (ESC) and correlate with a malignant phenotype. Although this amplicon spans a region of several megabases and harbors numerous genes, CCND1 and EMS1 are thought to be the relevant candidates in ESC. We investigated whether the putative transforming gene MYEOV, mapping 360 kb centromeric to CCND1 and activated concomitantly with CCND1 in a subset of t(11;14)(q13;q32) positive multiple myeloma cell lines, represents a target of 11q13 amplification in ESC. To evaluate the role of MYEOV in ESC, we tested 31 ESC cell lines and 48 primary tumors for copy number levels of MYEOVand demonstrated that MYEOV was always coamplified with CCND1. However, MYEOV expression levels correlated only inconsistently with DNA amplification data. Treatment with the demethylating agent 5-aza-2'-deoxycytidine restored MYEOV expression in a subset of cell lines exhibiting DNA amplification without high MYEOV expression, suggesting that MYEOV is transcriptionally silenced by a DNA methylation mechanism in most of the latter cell lines. Our results indicate that MYEOV is a coamplified gene with CCND1 at 11q13, but its activation is sometimes inhibited by an epigenetic mechanism.

Azacitidine↗
PubMed2002

Four cases of panic disorder successfully treated with Kampo (Japanese herbal) medicines: Kami-shoyo-san and Hange-koboku-to.

Kampo medicines have been used to treat patients with psychogenic disorders from ancient times. In the present report the cases are described of four patients with panic disorder successfully treated with Kampo medicines. These four patients fulfilled the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria for panic disorder with agoraphobia. The Kampo medicine Kami-shoyo-san (TJ-24) relieved panic attacks, anticipatory anxiety and agoraphobia in two patients, and Hange-koboku-to (TJ-16) relieved these symptoms in the other two patients. The patients in whom Kami-shoyo-san was effective were older and complained of more symptoms than those in whom Hange-koboku-to was effective. These Kampo medicines may be useful as additional or alternative treatments for panic disorder.

Adult↗
PubMed2002

Indications for abdominal para-aortic lymph node dissection in patients with esophageal squamous cell carcinoma.

BACKGROUND: Abdominal para-aortic lymph node (APAL) dissection of esophageal cancer is not widely accepted. The aim of this article is to propose the indications for APAL dissection in esophageal cancer patients from the viewpoint of micrometastases. METHODS: To evaluate the value of APAL dissection in patients with esophageal cancer, the status of APAL metastases and recurrence in 230 patients with esophageal squamous cell carcinoma (1989 to 1998) was examined retrospectively. On the basis of our findings, 16 patients received a prophylactic APAL dissection from January 1999 to March 2001. Micrometastases in the dissected lymph nodes were examined using cytokeratin staining and reverse transcription-polymerase chain reaction of squamous cell carcinoma antigen messenger RNA. RESULTS: Among the 230 patients who had esophageal squamous cell carcinoma, 21 had APAL metastases (including micrometastases) or APAL recurrence. Among the 21 patients with APAL metastases and recurrence, 20 (95.2%) had metastases (including micrometastases) in perigastric lymph nodes (paracardial and lesser curvature nodes). Among 51 patients with lower thoracic esophageal carcinoma, 13 (25.5%) had APAL metastases or recurrence. On the basis of these results, prophylactic APAL dissection was performed in patients with lower thoracic esophageal cancer who were suspected of perigastric lymph node metastases during operations. APAL metastases (including micrometastases) were detected in 6 (38%) of these patients, and 2 patients with APAL micrometastases survived without recurrence. However, 7 patients had hematogenic recurrence after the operation. CONCLUSIONS: Our results suggested that the indications for APAL dissection were limited. Patients with lower thoracic esophageal cancer who are suspected to have perigastric lymph node metastasis and APAL micrometastases may be considered for APAL dissection.

Adult↗
PubMed2002

Gene expression of cell surface antigens in the early phase of murine influenza pneumonia determined by a cDNA expression array technique.

BACKGROUND: Influenza virus is a worldwide health problem with significant economic consequences. To study the gene expression pattern induced by influenza virus infection, it is useful to reveal the pathogenesis of influenza virus infection; but this has not been well examined, especially in vivo study. AIMS: To assess the influence of influenza virus infection on gene expression in mice, mRNA levels in the lung and tracheal tissue 48 h after infection were investigated by cDNA array analysis. METHODS: Four-week-old outbred, specific pathogen free strain, ICR female mice were infected by intra-nasal inoculation of a virus solution under ether anesthesia. The mice were sacrificed 48 h after infection and the tracheas and lungs were removed. To determine gene expression, the membrane-based microtechnique with an Atlas cDNA expression array (mouse 1.2 array II) was performed in accordance with the manual provided. RESULTS AND CONCLUSIONS: We focused on the expression of 46 mRNAs for cell surface antigens. Of these 46 mRNAs that we examined, four (CD1d2 antigen, CD39 antigen-like 1, CD39 antigen-like 3, CD68 antigen) were up-regulated and one (CD36 antigen) was down-regulated. Although further studies are required, these data suggest that these molecules play an important role in influenza virus infection, especially the phase before specific immunity.

Adenosine Triphosphatases↗
PubMed2002

The effect of interleukin-15 on the expression of killer-cell immunoglobulin-like receptors on peripheral natural killer cells in human.

Interleukin (IL)-15 has emerged as a key regulator of both natural killer (NK) cell differentiation and activation. The aim of the present study was to investigate the expansion of the population of cells expressing killer-cell immunoglobulin-like receptors (CD158a and CD158b) in human peripheral lymphocytes by treatment with IL-15. One million peripheral lymphocytes were cultured in RPMI1640 medium alone or in medium containing IL-2 at 100 U/ml or IL-15 at 0.1, 1.0, or 10.0 ng/ml for 48 h. After each incubation, we assessed the natural killing activity and the population of CD16(+)CD158a(+)/b(+) cells and CD8(+)CD158a(+)/b(+) cells. IL-15 increased the NK activity and expanded the populations of CD16(+)CD158a(+)/b(+) cells and CD8(+)CD158a(+)/b(+) cells. These actions were dose dependent, and the effects of IL-15 at 1.0 ng/ml were close to those of IL-2 at 100 U/ml. These findings suggest that IL-15 induces the effector functions of resting NK cells throughout the body, and thereby plays a critical role in the activation of tissue-associated immune responses.

Cells, Cultured↗