Search PubMed⌕ Search

Biomedical subjects

K Chayama

Publications and source records attributed to K Chayama.

At least 73 records · Page 4Linked to original sources
PubMed2001

Long-term interferon therapy for 1 year or longer reduces the hepatocellular carcinogenesis rate in patients with liver cirrhosis caused by hepatitis C virus: a pilot study.

BACKGROUND AND METHODS: In order to elucidate the influence of a long-term administration of interferon on the appearance rates of hepatocellular carcinoma (HCC) in hepatitis C virus (HCV)-related cirrhosis, we retrospectively analyzed 694 patients with cirrhosis. A total of 113 patients underwent interferon therapy, including 25 patients with a long-term administration of interferon for 1 year or more, and the other 581 patients received no antiviral drugs. RESULTS: Crude cumulative appearance rates of HCC in the interferon and the untreated groups were 14.1, and 28.4% at the end of the 5th year, and 36.7 and 52.5% at the end of the 10th year, respectively (P = 0.0028). As there was a waiting time between diagnosis and treatment (median 2.0 months, average 21.3 months) in the treated group, Cox proportional hazard analysis using a time-dependent covariate was introduced to evaluate the anticarcinogenic effect of interferon. Although male sex, higher alpha-fetoprotein, older age, lower albumin concentration, and lower platelet count significantly increased the carcinogenesis rate, interferon was not a significant contributing factor to the carcinogenesis rate as a whole (hazard ratio = 0.83, P= 0.32). When the patients with interferon were divided into two groups according to therapy duration, long-term interferon therapy significantly decreased the hepatocellular carcinogenesis rate after an adjustment by significant covariates (hazard ratio = 0.28, P= 0.0048). CONCLUSION: When interferon is administered for 12 months or longer, effective cancer prevention will be achieved, even in patients with HCV-related cirrhosis.

Adult↗
PubMed2001

Clinicopathological features of gastric mucosa-associated lymphoid tissue lymphoma: a comparison with diffuse large B-cell lymphoma without a mucosa-associated lymphoid tissue lymphoma component.

BACKGROUND AND AIMS: The aim of this study was to clinicopathologically distinguish the pathogenesis of gastric mucosa-associated lymphoid tissue (MALT) lymphoma and diffuse large B-cell lymphoma without a MALT lymphoma component (DLL). METHODS: We investigated clinicopathological features of these gastric lymphomas including age, sex ratio, tumor location and depth, macroscopic appearance, and infection with Helicobacter pylori of these gastric lymphomas and hepatitis viruses in 24 patients with gastric low-grade MALT lymphoma, 10 patients with high-grade MALT lymphoma, and 19 patients with DLL. The frequency of H. pylori infection in lymphoma patients was compared with that in age- and sex-matched control subjects. RESULTS: There was a predominance of females with MALT lymphoma (male to female ratio, 8/16 for low-grade MALT lymphomas and 1/9 for high-grade MALT lymphomas), and there was a predominance of males with DLL (male to female ratio, 13/6); the ratios differed significantly (P < 0.05). Ninety-two percent of low-grade MALT lymphomas and 80% of high-grade MALT lymphomas were confined to the mucosal and submucosal layers, but lymphoma cells invaded the muscular layer or more deeply in 74% of DLL. Helicobacter pylori infection occurred significantly more often in patients with low-grade MALT lymphoma than in age- and sex-matched controls (96 vs 67%, P < 0.01). Conversely, the frequency of H. pylori infection in DLL patients did not differ from that in controls. CONCLUSIONS: These data suggest that H. pylori infection may be associated with the development of gastric MALT lymphoma, but not DLL, and that MALT lymphoma and DLL may have a different pathogenesis.

Adult↗
PubMed2001

Clinicopathologic features and endoscopic treatment of superficially spreading colorectal neoplasms larger than 20 mm.

BACKGROUND: A colorectal neoplasm that spreads superficially over the mucosa is known as a laterally spreading tumor. The clinicopathologic features of these large lesions and the efficacy and safety of endoscopic mucosal resection (EMR) were studied retrospectively. METHODS: Surgically or endoscopically resected laterally spreading tumors larger than 20 mm in diameter were studied. Lesions were divided into 2 macroscopic subtypes: F-type, composed of superficially spreading lesions with a flat and smooth surface, and G-type, composed of superficially spreading aggregates of nodules that form relatively flat, broad-based lesions with granulonodular and uneven surfaces. RESULTS: Thirty-three lesions were of the F-type and 87 the G-type. G-type (mean +/- SD, 35.3 +/- 11.4 mm) lesions were significantly larger (p < 0.01) than F-type (26.0 +/- 7.2 mm) lesions. F-type lesions had a significantly higher frequency of invasive cancer (27.2%) than G-types (10.3%)(p < 0.05). Of the 120 lesions, 81 (67.5%) were resected endoscopically. Patients with 78 of these lesions were followed postoperatively for 60.8 +/- 20.1 months. The rate of local recurrence of endoscopically treated tumors as determined at colonoscopy was 7.4% (6/78). These lesions were completely resected endoscopically. Distant metastases were not detected. Thirteen (16.0%) patients had local bleeding after EMR that was stopped endoscopically. Microperforation of the colonic wall as a result of EMR was diagnosed in 1 (1.2%) of 81 cases. CONCLUSIONS: Laterally spreading tumors larger than 20 mm, especially those of the G-type, have a low rate of invasion despite their relatively large size. The F-type lesion has a higher malignant potential than the G-type. EMR is an effective and safe treatment for the large laterally spreading tumor.

Adenoma↗
PubMed2001

Extracorporeal ultrasound is an effective diagnostic alternative to endoscopic ultrasound for gastric submucosal tumours.

BACKGROUND: Although endoscopic ultrasonography (EUS) is the best modality in the diagnosis of gastric submucosal tumours (G-SMT), it is still invasive and expensive. We evaluated the usefulness of transabdominal ultrasonography (US) as an alternative to EUS in the assessment and clinical management of G-SMT. METHODS: This is a prospective study of 156 successive patients who had been diagnosed with G-SMT by direct endoscopic visualization. For each patient, US was performed prior to EUS by an examiner who had not been informed about the site or the size of the patient's G-SMT beforehand. US diagnoses were compared with those ascertained by EUS. Diagnostic grade by US was divided into three groups: diagnosed (G-SMT was clearly demonstrated including location, site and type), detected (G-SMT was demonstrable but the type was not clear) and undetected (G-SMT was not demonstrated by US). RESULTS: We found that US can be an alternative to EUS for: 1) diagnosis of extramural compression, 2) diagnosis of G-SMT with size >30 mm in diameter, 3) detection and measurement of the size of a G-SMT from 21 to 30 mm in diameter, and 4) detection and measurement of the size of a G-SMT at both the gastric angle and cardia, regardless of the size of the tumour. Overall sensitivity and specificity for the detection of G-SMT were 82.5% and 100%, respectively. The diagnostic rates of G-SMT in each group were 60.1% (86/143) for diagnosed, 22.4% (32/143) for detected and 17.5% (25/143) for undetected. Approximate 95% (21/22) of G-SMT over 20 mm in diameter were at least detected, and 97% (30/31) of G-SMT over 30 mm in diameter were diagnosed by US. CONCLUSION: US can be an alternative method in the assessment of G-SMT, especially in the follow-up of patients already diagnosed.

Adolescent↗
PubMed2001

Calorie restriction reduced blood pressure in obesity hypertensives by improvement of autonomic nerve activity and insulin sensitivity.

Association between obesity and hypertension has been well recognized. A reduction in the body weight of over-weight hypertensive patients is a recommended lifestyle modification. The purpose of our study is to examine the relationship of insulin sensitivity and autonomic nervous activity with reduction of blood pressure by the calorie restriction. We evaluated the heart rate variability, nocturnal change of blood pressure and insulin resistance before and after a short-term low-calorie diet in 12 overweight essential hypertensives. After a week of standard diet (2000 kcal), 2 weeks of low-calorie diet (800 kcal) with normal sodium content induced a significant reduction in body mass index, triglyceride, fasting immunoreactive protein, homeostasis model assessment as an index of insulin resistance, and urinary excretion of sodium and potassium. Systolic blood pressure was significantly reduced both in daytime and night-time after the low-calorie diet (daytime, 134.5+/-6.0 to 122.0+/-4.1 mmHg; night-time, 126.8+/-5.2 to 113.4+/-7.2 mmHg). In daytime, diastolic blood pressure was also reduced (90.3+/-2.1 to 88.1+/-4.8 mmHg). Although heart rate was not significantly reduced, a rise of high frequency in night-time (346+/-82 to 572+/-108 ms2) and a fall of low frequency/high frequency in day-time (3.5+/-0.4 to 2.6+/-0.1) was significant after a low-calorie diet. In conclusion, weight loss by low-calorie diet with a constant intake of sodium, reduced blood pressure in obese hypertensives by improvement of vagal nervous activity and insulin resistance.

Adult↗
PubMed2001

Lamivudine therapy for spontaneously occurring severe acute exacerbation in chronic hepatitis B virus infection: a preliminary study.

OBJECTIVE: The nucleoside analogue lamivudine, a potent inhibitor of hepatitis B virus replication, has shown notable results in treating chronic hepatitis B. However, lamivudine has not been specifically tested for effectiveness against spontaneously occurring severe acute exacerbations of hepatitis in patients chronically infected with this virus. We addressed this issue in a pilot study. METHODS: Ten patients with chronic hepatitis B developed severe acute exacerbation spontaneously during follow-up; 3 of them developed hepatic failure shortly before entering the trial. Lamivudine was administered long-term to the 10 patients at a daily oral dose of 100 or 300 mg. RESULTS: All 3 patients with hepatic failure at initiation of treatment recovered dramatically. Of the remaining 7 patients, 5 recovered rapidly with lamivudine, but 2 progressed quickly to hepatic failure despite treatment. One died of sepsis and the other of multiorgan failure. In the 8 survivors, serum alanine transaminase activity decreased rapidly to normal with lamivudine therapy, and serum hepatitis B virus DNA level declined rapidly to undetectable levels. Serum total bilirubin concentrations normalized somewhat later. Prothrombin time improved steadily and gradually. Hepatitis B e antigen elimination or seroconversion was achieved in 3 survivors. No adverse effects were noted in any patient. All survivors had good quality of life with long-term lamivudine monotherapy. CONCLUSIONS: Lamivudine is effective, safe, and well tolerated by patients with spontaneous, severe, acute exacerbation complicating chronic hepatitis B virus infection, even in the presence of hepatic failure. Lamivudine appears to be an attractive therapeutic option and may represent the best choice.

Acute Disease↗
PubMed2001

Nonselective cation channel as a Ca(2+) influx pathway in pepsinogen-secreting cells of bullfrog esophagus.

In pepsinogen-secreting cells of bullfrog (Rana catesbeiana), recent evidence suggests that Ca(2+) release from internal stores followed by Ca(2+) influx across the plasma membrane elicits pepsinogen secretion. Such a Ca(2+) influx could be carried by a background current, potentiated by bombesin, that was found in these cells using the whole cell patch-clamp technique. The permeability ratio of Cs(+)-Rb(+)-K(+)-Na(+)-Li(+)-N-methyl-D-glucamine(+)-Ca(2+) was 1.01:1:1:0.86:0.72:0.54:0.34. The current was almost totally blocked by the nonselective cation channel blockers La(3+) (0.1 mM) and Gd(3+) (0.1 mM) and was activated by intracellular Ca(2+). These properties demonstrated that the current, which was activated by bombesin, was a nonselective cation current. At the same time, Gd(3+) suppressed pepsinogen secretion by 29 +/- 5.6% in isolated pepsinogen-secreting glands. These results are in accord with the idea that a nonselective cation channel in pepsinogen-secreting cells plays a role as a Ca(2+) influx pathway leading to secretion of pepsinogen in bullfrog esophageal mucosa.

Animals↗
PubMed2001

Pathogenic significance and organic virus levels in patients infected with TT virus.

Previous reports documented the recovery of a DNA virus from a patient with posttransfusion non-A-G hepatitis and named TT virus (TTV). Although the virus was initially detected as a causative agent of hepatitis, there is doubt about its pathogenicity. The aim of this study was to clarify the relationship between TTV and liver diseases. Histopathological examination of liver biopsies from 14 patients with TTV genotype 1 positive non-B, non-C and non-G chronic hepatitis showed mild fibrosis and periportal/piecemeal necrosis. Using the real-time detection (RTD)-PCR method, we found that TTV DNA levels of genotype 1 in liver samples from 3 such patients were 100- to 1,000-fold higher than those in the paired serum samples. Further investigation using various tissues from 2 autopsies of patients with hepatitis C with hepatocellular carcinoma revealed that the concentrations of TTV DNA in the liver were also higher than in serum samples. However, the highest TTV DNA concentrations in these 2 autopsies were found in the lung and bone marrow, respectively. Our results suggest that TTV may replicate in various tissues including the liver and may cause only mild liver damage.

Adult↗
PubMed2001

Expression of MRE11 complex (MRE11, RAD50, NBS1) and hRap1 and its relation with telomere regulation, telomerase activity in human gastric carcinomas.

The MRE11 complex (MRE11, RAD50, NBS1) are required for the repair of DNA double-strand breaks and have another important function in regulating telomere length. The silent information regulator (Sir) proteins required for telomere position effect also bind telomeres. hRap1 protein is a human ortholog of yeast Rap1 which regulates telomere length by interacting with TRF2 and is recruited to telomeres by TRF2. We examined the expression of the MRE11 complex (MRE11, RAD50, NBS1), Sir2 and hRAP1 in 20 gastric carcinomas by reverse transcription polymerase chain reaction and then analyzed the relation between telomerase activity and other telomerase components such as human telomerase reverse transcriptase (TERT), human telomerase RNA component (hTR), human telomerase-associated protein (TEP1), telomeric repeat binding factor 1 (TRF1), TRF2- and TRF1-interacting, ankyrin-related ADP-ribose polymerase (tankyrase) as well as TRF1-interacting nuclear protein 2 (TIN2). Of twenty gastric carcinomas examined, 13 (65%), 14 (70%), 16 (80%), 12 (60%) and 13 (65%) expressed MRE11, RAD50, NBS1, Sir2 and hRap1 at higher levels than corresponding nonneoplastic gastric mucosa, respectively. No obvious correlation was observed between MRE11 complex expression and telomerase activity or expression of TERT, hTR, TEP1, tankyrase and TIN2. Carcinomas with high TRF1 expression expressed significantly higher levels of MRE11 and RAD50 than those with low TRF1 expression (p < 0.05). On the other hand, carcinomas with high TRF2 expression expressed significantly higher levels of MRE11, NBS1 and hRap1 than those with low TRF2 expression (p < 0.05). These results suggest that gastric carcinomas with high TRF1 and TRF2 expression may need a large quantity of the MRE11 complex. Moreover, gastric carcinomas with high TRF1 expression may require a large quantity of hRap1.

Aged↗
PubMed2001

Activation of peroxisome proliferator-activated receptor gamma inhibits the growth of human pancreatic cancer.

OBJECTIVE: In the present study, we examined the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) in human pancreatic cancer and the possible effects of its ligand engagement on cell growth. METHODS: Seven human pancreatic cancer cell lines and 7 surgically resected human pancreatic cancer tissues were used as samples. The expression of PPARgamma was analyzed with reverse transcription-polymerase chain reaction and immunoblotting. The interaction between PPARgamma and PPAR-responsive element (PPRE) was examined by gel shift assay. Growth inhibition by thiazolidinediones was confirmed with anchorage-dependent and anchorage-independent growth assays. RESULTS: PPARgamma was detected in all cell lines tested and in 5 out of 7 cancer tissues (71%), but was not found in adjacent normal pancreatic tissues. Gel shift analysis revealed that the proteins in nuclear extracts of the pancreatic cancer cell line PANC-1 specifically bind to the PPRE. Cell growth was significantly inhibited by treatment with troglitazone and rosiglitazone in a dose- and time-dependent manner (p < 0.01). In contrast, a nonfunctional metabolic analog of troglitazone did not affect cell growth. CONCLUSION: These observations suggest that PPARgamma plays an important role in human pancreatic cancer growth and that ligand-induced activation of PPARgamma would be a useful strategy for treatment of human pancreatic cancer.

Antineoplastic Agents↗
PubMed2001

Effect of estrogen replacement therapy on endothelial function in peripheral resistance arteries in normotensive and hypertensive postmenopausal women.

Both menopause and hypertension are associated with endothelial dysfunction and are risk factors for coronary heart disease. We evaluated forearm resistance artery endothelial function in hypertensive postmenopausal women (HPW, n=57) and compared it with endothelial function in normotensive postmenopausal women (NPW, n=67). In addition, we evaluated the effects of long-term estrogen replacement therapy (ERT, conjugated equine estrogen at a dose of 0.625 mg daily for 12 weeks) on endothelial function in HPW (n=10) and NPW (n=35). Forearm blood flow (FBF) was measured by strain-gauge plethysmography during reactive hyperemia to assess endothelium-dependent vasodilation and after sublingual nitroglycerin (NTG) administration to assess endothelium-independent vasodilation. Basal FBF was similar in the NPW and HPW groups. The FBF in the HPW group during reactive hyperemia was significantly lower than that in the NPW group. Increases in FBF after NTG were similar in the 2 groups. ERT decreased the LDL cholesterol concentration and circulating ACE activity and increased estradiol and HDL cholesterol in both groups. Basal blood pressures, heart rate, FBF, and body weight did not change with ERT. After 12 weeks of ERT, the maximal FBF response during reactive hyperemia increased significantly in both groups. The improvement in reactive hyperemia after ERT was significantly greater in the HPW group than in the NPW group (49+/-8 versus 17+/-5%, P<0.05). Changes in FBF after sublingual NTG administration were similar before and after 12 weeks of ERT. These findings suggest that continued ERT improves forearm resistance artery endothelial function in postmenopausal women and that this beneficial effect is greater in patients that are hypertensive.

Blood Pressure↗
PubMed2001

Sodium chloride loading does not alter endothelium-dependent vasodilation of forearm vasculature in either salt-sensitive or salt-resistant patients with essential hypertension.

The purpose of this study was to determine whether a high NaCl intake impairs endothelium-dependent and -independent vasodilation of forearm circulation in salt sensitive (SS) patients with essential hypertension. We evaluated the effects of intra-arterial acetylcholine (ACh) and isosorbide dinitrate (ISDN) on forearm hemodynamics in 29 patients with essential hypertension, while consuming a low NaCl (50 mmol/d) or high Na Cl (340 mmol/d) diet for 1 week. The forearm blood flow (FBF) was measured by strain-gauge plethysmography. Patients were classified as SS (n=12) or salt resistant (SR; n=17) based on salt-induced changes in blood pressures. The FBF responses of ACh and ISDN were similar in the SS and SR patients while on either NaCl diet, and was not altered by salt loading (ACh, SS: low NaCl 22.8+/-4.3 vs. high NaCl 21.1+/-3.6 ml/min per 100 ml, SR: low NaCl 22.5+/-4.0 vs. high NaCl 23.3+/-4.1 ml/min per 100 ml; ISDN, SS: low NaCl 13.9+/-2.1 vs. high NaCl 14.1+/-2.2 ml/min per 100 ml, SR: low NaCl 13.8+/-2.3 vs. high NaCl 14.0+/-2.2 ml/min per 100 ml). There were no significant differences in the vascular responses to ACh and ISDN in the presence of N(G)-monomethyl-L-arginine, a nitric oxide synthase inhibitor, in either group for either NaCl diet. These findings suggest that forearm resistance artery endothelial function may not be influenced by salt loading in either SS patients which finding may play a role in determining salt sensitivity in patients with essential hypertension or SR patients.

Diet, Sodium-Restricted↗
PubMed2001

Helicobacter pylori eradication therapy for high-grade mucosa-associated lymphoid tissue lymphomas of the stomach with analysis of p53 and K-ras alteration and microsatellite instability.

Recent studies have shown that 70-80% of low-grade mucosa-associated lymphoid tissue (MALT) lymphomas regress in response to eradication of Helicobacter pylori (H. pylori). However, there are no reports on whether gastric high-grade MALT lymphomas regress after H. pylori eradication. We performed H. pylori eradication therapy in 4 patients with stage I, high-grade MALT lymphoma after obtaining their informed consent. H. pylori infection was observed in all 4 patients. The patients were treated with proton-pump inhibitor-based eradication therapy for 1 or 2 weeks, and then underwent endoscopic examination and biopsy sampling. H. pylori eradication was achieved in all 4 patients. Six months after eradication treatment, 2 patients showed complete regression of the lymphoma and 2 patients showed no change. The 2 patients with non-responding lymphoma were then treated with an additional chemotherapy (CHOP regimen), whereupon the tumors completely regressed. These patients, followed-up at least 18 months after eradication treatment, showed no recurrence. We also examined genetic alteration of the p53 and K-ras genes and microsatellite instability in these high-grade MALT lymphomas. One patient with a tumor that showed no change after H. pylori eradication, had a loss of heterozygosity of the p53 gene. No other genetic alterations were detected among the patients. Our results indicate that the eradication of H. pylori may be effective not only for patients with low-grade MALT lymphoma but also for patients with high-grade MALT lymphoma. The treatment may be efficacious as a first-line therapy for patients with high-grade MALT lymphoma. However, our sample size was limited and further studies are needed to clarify the issue.

Aged↗
PubMed2001

MUC1 and cathepsin D expression in early colorectal carcinoma showing V type pit pattern.

The relation between MUC1, cathepsin D expression, and histologic features in early colorectal carcinomas (CRCs) with V type pit pattern was examined in 78 patients. We classified V type pit pattern into two grades (VA, VN) and we subclassified the VN type pit pattern into three subtypes (Grade A, B, and C) according to the degree of appearance of VN type pit pattern. At the tumor surface, the status of desmoplastic reaction and pit disorder or destruction were subclassified histologically into three grades (-, +, ++). MUC1 and cathepsin D expression were examined immunohistochemically at a superficial level and at the deepest part of the tumor invasion. MUC1 expression showed a significant correlation with high grade carcinoma, desmoplastic reaction (+) levels in VA type pit pattern (P<0.05), and high grade carcinoma, sm2 and sm3 lesions, desmoplastic reaction (+) and (++) levels, pit disorder or destruction (+) and (++) levels in VN type pit pattern (P<0.05). Cathepsin D expression had a significant correlation with m and sm1 lesions and desmoplastic reaction (-) levels in VN type pit pattern (P<0.05). In VA type pit pattern, a significant correlation between cathepsin D expression and histologic findings was absent. The incidence of MUC1 expression in VN.Grade B and C type pit pattern was significantly higher than that in VA and VN.Grade A type pit pattern (P<0.05). The incidence of cathepsin D expression in VA, VN.Grade A and B type pit pattern was significantly higher than that in VN.Grade C type pit pattern (P<0.05). MUC1 expression (+) or (++) levels at the deepest part of a tumor was identical to that (+) or (++) levels at the superficial part except for one case. Cathepsin D expression at the deepest part of a tumor differed from that at the superficial part. Desmoplastic reaction may be related to MUC1 and cathepsin D expression; however, pit disorder or destruction may be related to only MUC1 expression in V type pit pattern. MUC1 expression at the superficial part of a tumor may be related to expression at the deepest part; however, cathepsin D expression at the superficial part may not be related to expression at the deepest part in submucosal CRCs with V type lesions.

Cathepsin D↗
PubMed2001

Expression of telomeric repeat binding factor 1 and 2 and TRF1-interacting nuclear protein 2 in human gastric carcinomas.

Telomeric repeat binding factor 1 (TRF1) and 2 (TRF2) may play key roles in the maintenance of telomere function. TRF1 negatively regulates telomere elongation, while TRF2 protects the chromosome ends by inhibiting end-to-end fusions. We examined the expression of TRF1 and TRF2 in 20 gastric carcinomas by reverse transcription polymerase chain reaction and then analyzed the relation with telomerase activity and other telomerase components such as human telomerase reverse transcriptase (TERT), human telomerase RNA component (hTR), human telomerase-associated protein (TEP1) and TRF1-interacting, ankyrin-related ADP-ribose polymerase (tankyrase) as well as TRF1-interacting nuclear protein 2 (TIN2). Of 20 gastric carcinomas examined, 10 (50%) and 12 (60%) expressed TRF1 and TRF2 at higher levels than did non-neoplastic mucosa, respectively. No obvious correlation was observed between TRF1 expression and telomerase activity or expression of TERT, hTR and TEP1. Carcinomas with high TRF1 expression expressed significantly higher levels of tankyrase and TIN2 than did those with low TRF2 expression (p<0.05). The telomerase activities and the levels of TERT, hTR and TEP1 showed tendency to be lower in tumors expressing TRF1 at low levels, although it was not significant. On the other hand, carcinomas with short telomere length (shorter than 2 Kbp) expressed significantly stronger telomerase activities and higher TRF1 expression (p<0.05) and tended to express TRF2 and TIN2 at higher levels than those with long telomere length. The results suggest that gastric carcinomas with short telomeres need high levels of telomerase activity and large quantity of TRFs and TIN2, whereas those with long telomeres do not require high levels of telomerase activity and telomere associated proteins.

Aged↗
PubMed2001

Endothelial dysfunction is an independent factor responsible for vasospastic angina.

In order to evaluate peripheral endothelial function in patients with vasospastic angina (VSA), we measured flow-mediated dilation (FMD) of the brachial artery in patients with VSA and compared it with FMD in patients without VSA. Endothelial dysfunction is considered one of the mechanisms underlying VSA. However, its exact role remains to be clarified. The study included 30 patients with positive spasm-provocational test results without evidence of significant coronary stenosis (VSA group) and 30 patients with negative spasm-provocational test results without evidence of significant coronary stenosis (control group). In each patient, brachial artery diameter responses to hyperemic flow and glyceryl trinitrate spray were measured using high-resolution ultrasound. The carotid intima-media thickness was also measured as a marker of systemic atherosclerosis. FMD was lower in the VSA group (4.8+/-0.5%) compared with the control group (9.4+/-0.7%, P<0.0001). In the VSA group, FMD was not affected by coronary risk factors or the presence of atherosclerotic changes on coronary angiography. Glyceryl trinitrate-induced dilation did not differ between the two groups. The intima-media thickness was comparable between the VSA (0.85+/-0.04 mm) and control groups (0.81+/-0.05 mm). These findings indicated that peripheral endothelial function is impaired only in the VSA group, whereas the atherosclerotic changes were similar in the two groups. We conclude that endothelial dysfunction may be an independent factor responsible for the development of VSA.

Aged↗
PubMed2000

Separation of bisphenol A and three alkylphenols by micellar electrokinetic chromatography.

Analytical conditions of pH, surfactants, and additives were investigated for the simultaneous separation of bisphenol A and alkylphenols by micellar electrokinetic chromatography. Reproducibility of migration time was improved at higher pH (pH 8.0). When five surfactants having linear alkyl chains or four bile salts were used, the separation of hydrophobic phenols and 4-nonylphenol isomers was not achieved. In order to improve the separation, the use of additives with sodium dodecyl sulfate solution was investigated. The separation of hydrophobic phenols was improved by the addition of organic solvents, however, isomers were not separated. Their separation was achieved by the addition of beta- or gamma-cyclodextrin.

Benzhydryl Compounds↗