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Biomedical subjects

H Yamaguchi

Publications and source records attributed to H Yamaguchi.

At least 109 records · Page 6Linked to original sources
PubMed2001

Other primary cancers occurring after treatment of superficial oesophageal cancer.

BACKGROUND: Recent advances in endoscopic diagnosis and treatment have led to better prognosis for patients with superficial oesophageal cancer. The incidence of subsequent other primary cancer (SOPC) has become a new problem for patients who survive after treatment of superficial oesophageal cancer. METHODS: Between 1966 and 1998, 368 patients with superficial oesophageal cancer, histologically confirmed as squamous cell carcinoma after resection, were reviewed for the presence of SOPC. RESULTS: Among the 368 patients, 43 developed SOPC. The most frequent sites of SOPC were the stomach (11 patients) and hypopharynx (11). Subsequent cancers of the stomach and hypopharynx developed significantly more frequently in heavy smokers. The 5-year cumulative occurrence rate of subsequent cancers within the fields of endoscopy of the upper gastrointestinal tract (stomach, hypopharynx and residual oesophagus) was 15 per cent. CONCLUSION: Gastric and hypopharyngeal cancers were frequently found after resection of superficial oesophageal cancer. A history of heavy smoking at the time of initial resection may be a risk factor. To make an early diagnosis of subsequent cancers, follow-up observation by upper gastrointestinal endoscopy is important after treatment of oesophageal cancer.

Carcinoma, Squamous Cell↗
PubMed2001

Characterization of platelet-derived growth factor-induced p38 mitogen-activated protein kinase activation in vascular smooth muscle cells.

BACKGROUND: The mitogen-activated protein (MAP) kinase super-family plays a crucial role in cell growth and differentiation and even in programmed cell death in response to diverse extracellular stimuli. The platelet-derived growth factor (PDGF)-BB is well known to promote the proliferation of vascular smooth muscle cells (VSMC) via extracellular-regulated protein kinases (ERKs), leading to the development of cardiovascular diseases. However, it has not yet been clarified whether PDGFs that include other isoforms can activate the other parallel signal transduction pathways, c-jun NH2-terminal protein kinase (JNK) and p38 MAP kinase (p38), in VSMC. In this study, we investigated the effect of PDGFs on p38 activation in cultured rat VSMC. MATERIALS AND METHODS: After stimulation by PDGFs with SB-203580 or PD-98059, the cells were solubilized, and the expressions of MAP kinases, MAP kinase kinases (MKKs), phosphorylated DNA-binding proteins, and cyclooxigenases (COXs) were examined by immunoblot analysis. RESULTS: PDGFs activated p38 phosphorylation dose-dependently, and the phosphorylations were specifically inhibited by SB-203580 but not by PD-98059. PDGFs also activated the phosphorylation of MKK 3/MKK 6 but not that of either stress-activated protein kinase/ERK kinase or JNK. PDGFs affected the activation of a cyclic AMP response-element binding protein, which was inhibited by SB-203580. However, the activating transcription factor-2 was not activated by PDGFs. Interestingly, the stimulation of PDGFs for 72 h enhanced the level of COX-2, and these levels were decreased by SB-203580. CONCLUSION: These results have clarified that PDGFs activate the p38 cascade via an MKK 3/6 pathway, independently of the ERK cascade, and subsequently regulate the level of COX-2 in rat VSMC, providing that PDGFs influence the inflammatory process in the vascular wall.

Activating Transcription Factor 2↗
PubMed2001

The influence of two concentrations of sodium hypochlorite on human blood: changes in haemolysis, pH and protein.

AIM: To evaluate the in vitro effect of 2.5% and 5.0% sodium hypochlorite (NaOCl) on human blood. METHODOLOGY: Each concentration of NaOCl was reacted with human blood for 5 min at volume ratios of 1 : 1, 1 : 6, 1 : 12, each creating changes in colour, pH and temperature. Reaction suspensions were separated by centrifugation, and absorption measurements made for separated bilirubin, Fe, and protein supernatants. Each supernatant was desalted, lyophilized, and treated by SDS polyacrylamide gel electrophoresis (SOS-PAGE). RESULTS: Increased ratios and concentrations of NaOCl caused an increase in both pH and temperature. Protein supernatants tended to decompose on SDS-PAGE. Supernatants showed increased decolourisation with 5.0% NaOCl. Concentrations of bilirubin, Ferrum and protein in supernatants decreased with increased NaOCl concentration. NaOCl had an effect on the protein component in blood. CONCLUSIONS: These data suggest that changes in molecular structure are due to the chemical effects of NaOCl. Protein bands tended to show low molecular weight, suggesting that haemoglobin components effect the oxidation-reduction reaction.

Adult↗
PubMed2001

In-vitro and in-vivo anti-Trichophyton activity of essential oils by vapour contact.

The minimum inhibitory doses (MIDs) of essential oils by vapour contact to inhibit the growth of Trichophyton mentagrophytes and Trichophyton rubrum on agar medium were determined using airtight boxes. Among seven essential oils examined, cinnamon bark oil showed the least MID, followed by lemongrass, thyme and perilla oils. Lavender and tea tree oils showed moderate MID, and citron oil showed the highest MID, being 320 times higher than that of cinnamon bark oil. The MID values were less than the minimum inhibitory concentration (MIC) values determined by agar dilution assay. Furthermore, the minimum agar concentration (MAC) of essential oils absorbed from vapour was determined at the time of MID determination as the second antifungal measure. The MAC value by vapour contact was 1.4 to 4.7 times less than the MAC remaining in the agar at the time of MIC determination by agar dilution assay. Using selected essential oils, the anti-Trichophyton activity by vapour contact was examined in more detail. Lemongrass, thyme and perilla oils killed the conidia, inhibited germination and hyphal elongation at 1-4 micrograms ml-1 air, whereas lavender oil was effective at 40-160 micrograms ml-1 air. The in-vivo efficacy of thyme and perilla oils by vapour contact was shown against an experimental tinea pedis in guinea pigs infected with T. mentagrophytes. These results indicated potent anti-Trichophyton action of essential oils by vapour contact.

Agar↗
PubMed2001

Evaluation of pancreatic secretion after administration of secretin: application of magnetic resonance imaging.

BACKGROUND: To evaluate pancreatic exocrine function, we measured the changes in T2 enhanced hydrograhic intensity on magnetic resonance (MR) images of the pancreas following an injection of secretin, which is representative of the changes in duodenal fluid volume. METHODS: The subjects were 10 patients with normal pancreatic function (N > 70% detected by using a pancreatic function diagnostant test) and 12 patients with hypo-function, including those with mild hypo-function (MH, 50-70%, six patients) and severe hypo-function (SH < 50%, six patients). RESULTS: In the N group, T2 enhanced intensity of the pancreas increased to a maximum value (more than 10% compared with baseline) within 5 min of stimulation, then gradually decreased. No significant difference in the response was observed between the head and body of the pancreas. Changes in the MH group were similar to those of the N group. In contrast, significantly lower changes in T2 enhanced intensity were observed in SH group, relative to both the N and MH group (P < 0.05). The amount of secretin-induced increase in duodenal fluid after 16 min was not significantly different among the three groups. Furthermore, an evaluation of the residual pancreatic tissue after a pancreatoduodenectomy was also feasible. CONCLUSIONS: Our results indicate that the MR-secretin test is useful for the evaluation of severe pancreatic exocrine dysfunction. The diagnostic test is simple, direct and non-invasive.

Adult↗
PubMed2001

Comparison of the expression of ABH/Lewis-related antigens in polypoid and non-polypoid growth types of colorectal carcinoma.

BACKGROUND AND AIMS: Colorectal tumors can be classified based on their growth pattern into the polypoid growth-type (PG-type) and non-polypoid growth-type (NPG-type). To ascertain whether there is any relationship between the expression of particular blood group-related antigens (A, B, H, Lewis (Le)a, sialyl Le(a), Le(x), sialyl Le(x)) in a colorectal tumor, and a tumor having polypoid or non-polypoid growth, we examined 78 PG-type and NPG-type colorectal cancers. METHODS: Fourteen PG-type and 64 NPG-type colorectal carcinomas were subjected to immunohistochemical analyses by using monoclonal antibodies against A, B, H, Le(a), sialyl Le(a), Le(x) and sialyl Le(x). RESULTS: The patients with NPG-type carcinomas had a significantly younger age of onset, significantly smaller maximal tumor diameter, significantly higher rate of lymph node metastasis and significantly worse prognosis than those with PG-type carcinomas. Among the 32 tumors of patients with blood type A or AB, isoantigen A was expressed in a significantly larger percentage of NPG-type carcinomas than PG-type carcinomas (95.8 vs 62.5%, respectively; P=0.014). Among all 78 tumors, sialyl Le(x) antigen was expressed in a significantly larger percentage of NPG-type than PG-type carcinomas (90.6 vs 64.3%, respectively; P=0.010). Multivariate analysis using the logistic regression model revealed that isoantigen A and sialyl Le(x) expression were independent predictive risk factors for the development of NPG-type colorectal carcinoma. CONCLUSIONS: These data suggest that the expression of isoantigen A and sialyl Le(x) in a colorectal carcinoma partially determines whether the tumor will have polypoid or non-polypoid growth.

ABO Blood-Group System↗
PubMed2001

Measurement of serum hyaluronic acid level during the perioperative period of liver resection for evaluation of functional liver reserve.

BACKGROUND AND AIM: The serum hyaluronic acid (HA) concentrations reflect the degree of hepatic fibrosis and sinusoidal endothelial cell damage. The HA concentrations were examined to evaluate liver damage during the perioperative period of hepatectomy. METHODS: The HA level of serum samples from 79 patients who underwent a hepatectomy was measured, and the results were compared to conventional liver function tests, the degree of fibrosis, liver regeneration and complications. RESULTS: Hyaluronic acid concentrations correlated with the severe fibrosis or histological activity index, and also correlated with liver function tests including transaminase level, platelet counts, prothrombin time activity, indocyanine green retention rate at 15 min (ICG R15), liver activity at 15 min by technetium-99m galactosyl human serum albumin scintigraphy (LHL 15), and portal pressure. The HA level postoperatively correlated with liver function, especially with total bilirubin. Hyaluronic acid levels at day 28 postoperatively correlated with ICG R15 and LHL 15. The hyaluronic acid level before surgery and at day 28 postoperatively correlated with the regeneration of remnant liver in major hepatectomy. The HA levels were significantly higher in patients with hepatic failure or prolonged ascites. CONCLUSION: Our results indicate that the measurement of the HA level is useful for monitoring liver damage or predicting complications associated with liver surgery.

Adult↗
PubMed2001

Spontaneous regression over a 16-year period of tachyarrhythmias to sick sinus syndrome and complete atrioventricular block in a young patient with Ebstein's anomaly.

A 25-year-old man with Ebstein's anomaly showed spontaneous regression of tachyarrhythmias to sick sinus syndrome and complete atrioventricular block over a 16-year period. This is the first clinical report supporting the hypothesis that abnormal cell death might contribute to the disturbance of the heart conduction system in Ebstein's anomaly.

Adult↗
PubMed2001

Detection of Chlamydia pneumoniae antigenin PBMNCs of healthy blood donors.

BACKGROUND: Because it has been increasingly recognized that Chlamydia pneumoniae may be linked to some chronic inflammatory diseases, including atherosclerosis, detection of this pathogen in blood from patients may be valuable in the diagnosis of such diseases. However, the prevalence of chlamydia in the blood of healthy donors has not yet been extensively studied. STUDY DESIGN AND METHODS: The presence of C. pneumoniae in PBMNCs obtained from healthy persons who donated blood for blood transfusion was assessed by a PCR that was specific for the C. pneumoniae 16S rRNA gene and by the use of staining with FITC-conjugated chlamydia MoAb. RESULTS: Twenty-one (8.9%) of 237 blood samples tested showed the presence of C. pneumoniae DNA and antigen in the PBMNCs. There was no significant difference in the presence of chlamydia in blood according to sex or to age between 20 and 59 years of age. However, a possible seasonal variation in the presence of chlamydia in blood from healthy donors was suggested by the results obtained. CONCLUSION: A significant percentage of healthy donors carry C. pneumoniae, which may be a risk factor for some chronic diseases.

Adolescent↗
PubMed2001

Pre-operative serum levels of sialyl Tn antigen predict liver metastasis and poor prognosis in patients with gastric cancer.

AIMS: To clarify the prognostic value of preoperative serum levels of sialyl Tn antigen (STN) for survival of gastric cancer patients. METHODS: Pre-operative serum levels of STN, sialyl Lewis(a)antigen (CA19-9) and carcinoembryonic antigen (CEA) were examined in 180 patients who underwent resection of gastric cancer. Patients were divided into high and low antigen groups on the basis of a selected diagnostic-based cut-off value. Correlation between high antigen serum levels, established clinicopathologic factors and prognosis was examined by univariate and multivariate analysis. RESULTS: Twenty-eight patients (15.6%) were classified as high STN; 37 (20.6%) as high CA19-9; and 33 (18.3%) as high CEA. The survival time of the high STN, CA19-9 or CEA group was shorter than that of the respective low-antigen group (P<0.0001, P=0.0008 or P=0.0002, respectively). Patients with stage III/IV tumours with high STN had a shorter survival time that those with low STN (P=0.0004). Cox's regression with multiple covariates showed that high serum STN is an independent factor predicting a worse outcome in gastric cancer patients. Multiple logistic regression analysis revealed that high serum STN is an independent predictor for the development of liver metastasis. CONCLUSIONS: Pre-operative high serum levels of STN predict both liver metastasis and poor prognosis after resection for gastric cancer.

Aged↗
PubMed2001

Expression of cytokines after meniscal rasping to promote meniscal healing.

PURPOSE: We have developed a new surgical procedure of rasping a meniscal surface to repair a tear in the avascular zone. This procedure stimulates vascular induction to the tear, resulting in meniscal healing. The purpose of this study was to elucidate the mechanism of vascular induction and meniscal healing. TYPE OF STUDY: Randomized trial. METHODS: A full-thickness longitudinal tear of 5 mm in length was created in the avascular zone of the anterior segment of both medial menisci of rabbits. Meniscal rasping of about 0.5 mm in depth was then done on the femoral surface of the left meniscus from the parameniscal synovium to the inner portion including the longitudinal tear, and the right meniscus was left untreated as a control. After surgery, at 1, 7, 14, 28, 56, and 112 days, 4 rabbits were killed, both medial menisci were resected, and immunohistochemical staining with monoclonal antibodies was used to quantify expression of interleukin-1alpha (IL-1alpha), transforming growth factor-beta1 (TGF-beta1), platelet-derived growth factor (PDGF), and proliferating-cell nuclear antigen (PCNA) on the femoral surface of the menisci. A positive ratio of immunostaining was encountered. RESULTS: The positive ratio of IL-1alpha, TGF-beta1, PDGF, and PCNA on the rasped surface area reached its peak at 1, 7, 14, and 7 days, respectively, after surgery, and thereafter gradually declined. Although the time course of the positive ratio was different among these cytokines, the positive ratio on the rasped surface was significantly higher than that on the control surface at the early stage of the observation period. CONCLUSIONS: The cytokine network on the rasped meniscal surface appears to be the key to explaining the mechanism of vascular induction and meniscal healing by meniscal rasping.

Animals↗
PubMed2001

Characterization of an inhibitory effect of pioglitazone on balloon-injured vascular smooth muscle cell growth.

This study investigates whether pioglitazone could suppress an atherogenic process such as balloon-injured carotid intimal thickening and the proliferation of vascular smooth muscle cells (VSMC). We first examined the effect of pioglitazone to determine whether it could suppress intimal thickening induced by balloon catheterization in Sprague-Dawley rats. After 14 days postcatheterization in the left common carotid artery, the neointimal layers were completely occupied by proliferated VSMC, and the area ratio of neointima to media treated with 10 mg/kg/d of pioglitazone was significantly decreased to 57%. Next, we evaluated the effect of pioglitazone on the proliferation of rat cultured VSMC. Piogliotazone dose-dependently decreased the values of DNA synthesis, total cellular protein content, phosphorylations of extracellular signal-regulated protein kinase 1/2 and mitogen-activated protein kinase kinase 1/2, and proliferative cell nuclear antigen in VSMC. Pioglitazone also inhibited the phosphorylation of Pyk2. We conclude that pioglitazone itself could be effective for suppressing the growth of VSMC and consequent carotid intimal thickening.

Animals↗
PubMed2001

Metastatic tumors to the stomach: analysis of 54 patients diagnosed at endoscopy and 347 autopsy cases.

BACKGROUND AND STUDY AIMS: There have been several published reports on metastatic lesions in the stomach, but the numbers of cases have been limited due to the low frequency of the condition. The present study examined the clinicopathological features of metastatic tumors in the stomach from distant sites in a large series of cases. PATIENTS AND METHODS: A total of 389 patients with gastric metastases from solid malignant tumors were examined between 1968 and 1998 at our institution. Of these, 347 were identified from a series of 6380 autopsy cases; 54 patients were diagnosed endoscopically while alive, 12 of whom had confirmation of the condition at autopsy. RESULTS: In the endoscopically diagnosed cases, the metastases presented as solitary (65%) or multiple lesions (35 %), and were more frequently located in the middle or upper third of the stomach. Although the endoscopic appearance often resembled that of submucosal tumor (51%) or primary gastric cancer (39%), the final diagnosis was easily obtained in over 90% of cases from endoscopic biopsies. In two cases of lung cancer and breast cancer, gastric metastases were found before the primary tumors. In the autopsy cases with solid malignancies, metastatic lesions to the stomach were found in 5.4%, and the lung, breast, and esophagus were common primary sites. Malignant melanoma was the most frequent tumor to metastasize to the stomach (29.6%). CONCLUSIONS: Since metastatic lesions to the stomach are rare, the above characteristics of the lesions should be borne in mind, and biopsies should be taken for precise diagnosis during endoscopic examinations.

Adult↗
PubMed2001

Acidic polysaccharides from rhizomes of Atractylodes lancea as protective principle in Candida-lnfected mice.

Prophylactic effects upon imunnosuppressed mice lethally infected by Candida albicans were examined in fractions prepared from a constituent herb of Juzen-taiho-to (TJ-48, Si-Quan-Da-Bu-Tang), rhizomes of Atractylodes lancea DC. The oral administration of water extract obtained from a residue after MeOH extraction of rhizomes significantly prolonged the survival period of the infected mice at a dose of 140 mg/kg/day compared with control mice, while the MeOH extract did not. In the crude polysaccharide fraction (F-2) obtained by EtOH precipitation of the water extract, a significant life-prolonging effect was observed by the administration of 70 mg/kg/day. F-2 was further fractionated, and the resulting strongly acidic polysaccharide fraction, F-2-2, had a protective effect at a dose of 17.5 mg/kg/day. This fraction mainly consisted of acidic pectic polysaccharides containing about 80% galacturonic acid. The protective activity of F-2-2 was lost by periodate oxidation, but not by protease digestion, suggesting that the polysaccharide component of F-2-2 plays a major role in the protective activity against Candida-infected mice.

Animals↗
PubMed2001

Sodium thiosulfate solution spray for relief of irritation caused by Lugol's stain in chromoendoscopy.

BACKGROUND: Mucosal iodine staining is known to improve the endoscopic visualization of esophageal squamous dysplasia and cancer. However, it often causes mucosal irritation leading to retrosternal discomfort. The clinical usefulness of sodium thiosulfate solution (STS) for easing symptoms induced by mucosal staining with Lugol's solution was evaluated in this study. METHODS: One hundred twenty healthy men over 50 years of age were enrolled in the study. They each underwent esophagogastroscopy including the spraying of Lugol's iodine solution (10 mL) on the mid and distal esophagus and were subsequently randomized into three groups: (I) no treatment (n = 40), (II) spraying of 20 mL of aluminum-magnesium hydroxide gel (Maalox) by means of endoscopic catheter (n = 40), and (III) spraying of 20 mL of 5% sodium thiosulfate solution by means of endoscopic catheter (n = 40). An hour after the endoscopic examination the subjects were asked to complete a questionnaire that addressed adverse symptoms induced by Lugol's iodine staining. RESULTS: Sodium thiosulfate solution spray substantially reduced adverse symptoms that lasted more than 30 minutes after chromoendoscopy, compared with the no-treatment group. There was no significant difference in the proportion of subjects with symptoms between the Maalox and no-treatment groups. Cost of sodium thiosulfate solution spray per use was $0.15 (15 yen). CONCLUSIONS: Sodium thiosulfate solution is recommended for routine use after Lugol's staining.

Coloring Agents↗
PubMed2001

Early outcome after minilaparotomy for the treatment of rectal cancer.

OBJECTIVE: To compare early outcomes of the minilaparotomy approach to the resection of rectal cancer with those of conventional laparotomy. DESIGN: Retrospective study. SETTING: University hospital, Japan. SUBJECTS: 18 patients who had complete resection through a minilaparotomy and 20 who had a conventional laparotomy served as the study and the control groups, respectively. Patients who were overweight or morbidly obese (body mass index >25) were excluded from the study. INTERVENTIONS: Complete resection through a skin incision less than 7 cm in length, or a conventional incision. MAIN OUTCOME MEASURES: Early postoperative outcomes. RESULTS: Postoperative time intervals to standing, walking, passing flatus, and removal of the urinary catheter, and analgesic requirements were significantly less in the minilaparotomy group (p = 0.007, p = 0.004, p = 0.02, p = 0.002, and p = 0.05, respectively). CONCLUSIONS: The minilaparotomy for complete resection of rectal cancer is less invasive than conventional laparotomy, and provides an attractive alternative in highly selected patients who are not overweight.

Aged↗
PubMed2001

Mechanisms of fluconazole resistance in Candida albicans isolates from Japanese AIDS patients.

Four Candida albicans isolates, TIMM 3163, TIMM 3164, TIMM 3165 and TIMM 3166, with reduced fluconazole susceptibility were obtained from three AIDS patients in Japan, and the mechanisms of their drug resistance were studied. All isolates showed lower levels of intracellular accumulation of fluconazole than ATCC 10231, a susceptible control strain of C. albicans. Increased amounts of CDR1 and CDR2 mRNA encoding putative ATP binding cassette (ABC) transporters were associated with the azole resistance of all TIMM isolates, apart from TIMM 3164. In addition, increased Cdr1p levels were immunodetected in the cell membrane fractions of all the TIMM strains except for TIMM 3164. Gene amplification was not responsible for CDR1 overexpression and there were no significant differences in the mRNA levels of CDR3 or CDR4 (ABC transporters) in the azole-susceptible and -resistant cells. CaMDR1 (a major facilitator superfamily) gene expression was not observed in any of the resistant isolates or the control strain. These results suggest that energy-dependent drug efflux associated with increased expression of CDR1 and CDR2 is involved in the fluconazole resistance mechanisms in two of the four isolates, TIMM 3165 and TIMM 3166. TIMM 3164 demonstrated energy-dependent drug efflux without overexpression of CDR1-4 or CaMDR1, indicating that some other pump may be operating. Despite showing low levels of drug efflux and overexpression of CDR1 and CDR2, efflux in TIMM 3163 was not energy dependent, suggesting that the expressed Cdr1p non-functional Cdr1p and that other resistance mechanisms may operate in this strain.

ATP Binding Cassette Transporter, Subfamily B, Mem↗