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Biomedical subjects

Y Amano

Publications and source records attributed to Y Amano.

At least 19 recordsLinked to original sources

Evaluation of modified crystal violet chromoendoscopy procedure using new mucosal pit pattern classification for detection of Barrett's dysplastic lesions.

BACKGROUND: Pit pattern diagnosis is important for endoscopic detection of dysplastic Barrett's lesions, though using magnification endoscopy can be difficult and laborious. We investigated the usefulness of a modified crystal violet chromoendoscopy procedure and utilised a new pit pattern classification for diagnosis of dysplastic Barrett's lesions. METHODS: A total of 1,030 patients suspected of having a columnar lined oesophagus were examined, of whom 816 demonstrated a crystal violet-stained columnar lined oesophagus. The early group of patients underwent 0.05% crystal violet chromoendoscopy, while the later group was examined using 0.03% crystal violet with 3.0% acetate. A targeted biopsy of the columnar lined oesophagus was performed using crystal violet staining after making a diagnosis of closed or open type pit pattern with a newly proposed system of classification. The relationship between type of pit pattern and histologically identified dysplastic Barrett's lesions was evaluated. RESULTS: Dysplastic Barrett's lesions were identified in biopsy samples with an open type pit pattern with a sensitivity of 96.0%. Further, Barrett's mucosa with the intestinal predominant mucin phenotype was closely associated with the open type pit pattern (sensitivity 81.9%, specificity 95.6%). CONCLUSIONS: The new pit pattern classification for diagnosis of Barrett's mucosa was found to be useful for identification of cases with dysplastic lesions and possible malignant potential using a crystal violet chromoendoscopic procedure.

Acetates↗

Interobserver agreement on classifying endoscopic diagnoses of nonerosive esophagitis.

BACKGROUND AND STUDY AIMS: The majority of patients with gastroesophageal reflux disease in Japan have low-grade esophagitis, including minimal changes. A modified Los Angeles classification of esophagitis, consisting of erosive esophagitis (grades A - D) and nonerosive esophagitis (grades M and N) has been proposed and is in clinical use in Japan. However, it is unclear whether nonerosive esophagitis with only undemarcated mucosal discoloration (grade M) is clinically significant, since interobserver variations in classification have not been investigated. The aim of the present study was therefore to evaluate interobserver variance and diagnostic agreement in the diagnosis of nonerosive esophagitis (grades M and N). MATERIALS AND METHODS: A total of 84 endoscopists were enrolled to assess the grade of esophagitis in 30 patients by viewing endoscopic images of the gastroesophageal junction. The images were projected onto a screen, and all of the endoscopists reviewed them concurrently. The diagnosis was selected from the following three categories in the modified Los Angeles classification: grades N, M, or A. The endoscopists were grouped according to their experience, whether they had a board license, and whether they had received specialist training in esophagitis. The kappa coefficient of reliability was calculated. RESULTS: The kappa coefficient of reliability for all the endoscopists in the diagnosis of cases of grade M and N nonerosive esophagitis was unacceptably low at 0.22 (95 % CI, 0.21 - 0.24). Endoscopists with a board license and those who had completed a special esophagitis diagnostic course had slightly higher kappa values (0.26; 95 % CI, 0.23 - 0.30 and 0.29; 95 % CI, 0.26 - 0.32), respectively. CONCLUSIONS: Interobserver agreement on the endoscopic diagnosis of nonerosive esophagitis (grades M and N) is too low to be of clinical value.

Clinical Competence↗

Pre-exposure to infectious hypodermal and haematopoietic necrosis virus or to inactivated white spot syndrome virus (WSSV) confers protection against WSSV in Penaeus vannamei (Boone) post-larvae.

Larvae and post-larvae of Penaeus vannamei (Boone) were submitted to primary challenge with infectious hypodermal and haematopoietic necrosis virus (IHHNV) or formalin-inactivated white spot syndrome virus (WSSV). Survival rate and viral load were evaluated after secondary per os challenge with WSSV at post-larval stage 45 (PL45). Only shrimp treated with inactivated WSSV at PL35 or with IHHNV infection at nauplius 5, zoea 1 and PL22 were alive (4.7% and 4%, respectively) at 10 days post-infection (p.i.). Moreover, at 9 days p.i. there was 100% mortality in all remaining treatments, while there was 94% mortality in shrimp treated with inactivated WSSV at PL35 and 95% mortality in shrimp previously treated with IHHNV at N5, Z1 and PL22. Based on viral genome copy quantification by real-time PCR, surviving shrimp previously challenged with IHHNV at PL22 contained the lowest load of WSSV (0-1x10(3) copies microg-1 of DNA). In addition, surviving shrimp previously exposed to inactivated WSSV at PL35 also contained few WSSV (0-2x10(3) copies microg-1 of DNA). Consequently, pre-exposure to either IHHNV or inactivated WSSV resulted in slower WSSV replication and delayed mortality. This evidence suggests a protective role of IHHNV as an interfering virus, while protection obtained by inactivated WSSV might result from non-specific antiviral immune response.

Animals↗

Helicobacter pylori infection influences symptomatic response to anti-secretory therapy in patients with GORD--crossover comparative study with famotidine and low-dose lansoprazole.

BACKGROUND AND AIM: Helicobacter pylori infection was reported to affect gastric acid secretion. We investigated the heartburn symptoms of patients with gastro-oesophageal reflux disease during sequential treatment with 40 mg of famotidine or 15 mg of lansoprazole to clarify whether H. pylori infection influences symptomatic response to anti-secretory therapy. SUBJECTS AND METHODS: The subjects were 33 gastro-oesophageal reflux disease patients, who had already been treated with a full dose of H2 receptor antagonist. First, famotidine at 20 mg b.i.d. was administered to the patients for 8 weeks. Second, famotidine was replaced with 15 mg of lansoprazole once in the morning for 8 weeks. Finally, 20 mg of famotidine was administered b.i.d. for 8 weeks instead of lansoprazole. Gastro-oesophageal reflux disease symptoms were assessed using an original visual analogue scale. RESULTS: The sequential symptomatic responses to famotidine and lansoprazole administration indicated that gastro-oesophageal reflux disease symptoms of patients during low-dose lansoprazole treatment were significantly less than those during famotidine treatment. Remission of symptoms was obtained significantly more often by famotidine therapy in patients with H. pylori infection than in patients without H. pylori infection. CONCLUSION: Low-dose lansoprazole is more effective than full-dose famotidine for the control of symptoms in patients with gastro-oesophageal reflux disease, and H. pylori infection influences the symptomatic response to H2 receptor antagonists.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Barrett's oesophagus with predominant intestinal metaplasia correlates with superficial cyclo-oxygenase-2 expression, increased proliferation and reduced apoptosis: changes that are partially reversed by non-steroidal anti-inflammatory drugs usage.

BACKGROUND: Cyclo-oxygenase-2 expression has been reported to play an important role in the metaplasia-dysplasia-carcinoma sequence in Barrett's oesophagus. However, the existence of cyclo-oxygenase-2 expressing cells in Barrett's epithelium is still uncertain. AIM: To identify the cells that express cyclo-oxygenase-2 protein and to investigate the relationship between cyclo-oxygenase-2 expression and mucin-phenotype of Barrett's epithelium. METHODS: Sections from 466 biopsy samples of Barrett's epithelium from 358 non-medicated patients were immunohistochemically examined for the cyclo-oxygenase-2 expression, mucin-phenotype, cell proliferation and apoptosis. RESULTS: Cyclo-oxygenase-2 expression was detected in 71.0% of Barrett's epithelium biopsy samples. In Barrett's epithelium with the gastric predominant mucin-phenotype, cyclo-oxygenase-2 expression was mainly found in stromal and deep epithelial cells, whereas in intestinal predominant mucin-phenotype, it was mostly in superficial epithelial cell. A significant elevation of proliferating cell nuclear antigen index and suppression of apoptotic index was observed in Barrett's epithelium with superficial epithelial cyclo-oxygenase-2 expression. Neither such elevation of proliferating cell nuclear antigen index nor the suppression of apoptotic index could be found in chronic non-steroidal anti-inflammatory drugs users. CONCLUSIONS: Barrett's epithelium with intestinal mucin and superficial epithelial cyclo-oxygenase-2 expression possess a higher proliferation potential, but this risk may be thwarted by non-steroidal anti-inflammatory drugs administration.

Anti-Inflammatory Agents, Non-Steroidal↗

Correlation between dietary glycemic index and cardiovascular disease risk factors among Japanese women.

OBJECTIVE: To examine the correlation between dietary glycemic index (GI) and cardiovascular disease (CVD) risk factors among subjects who consume white rice as a staple food. DESIGN: A cross-sectional study was conducted to explore the associations between dietary GI, dietary glycemic load (GL) and dietary intakes, and CVD risk factors. Dietary GI and GL were calculated from a 3-day (including two consecutive weekdays and one holiday) dietary records. SETTING: A weight-reduction program at a municipal health center in Tokyo, Japan. SUBJECTS: A total of 32 women aged 52.5+/-7.2 y participated in the weight-reduction program. RESULT: The GI food list made for the current study calculated for 91% of carbohydrate intakes measured. The mean dietary GI was 64+/-6, and the mean dietary GL was 150+/-37. Individuals in the highest tertile of GI consumed more carbohydrate, mostly from white rice (P<0.001), and less fat (P<0.01). Individuals in all three groups by tertile of GL showed similar tendencies. In the lowest GI tertile, the highest concentration of HDL-cholesterol and lowest concentration of triacylglycerol and immunoreactive insulin were observed (P<0.01). In the lowest GL tertile, the highest concentration of HDL-cholesterol and the lowest concentration of triacylglycerol were observed (P<0.05). CONCLUSION: Calculated dietary GI and GL were positively associated with CVD risk factors among the Japanese women who consumed white rice as a staple food.

Area Under Curve↗

IL-12 Production Induced by Agaricus blazei Fraction H (ABH) Involves Toll-like Receptor (TLR).

Agaricus blazei Murill is an edible fungus used in traditional medicine, which has various well-documented medicinal properties. In the present study, we investigated the effects of hemicellulase-derived mycelia extract (Agaricus blazei fraction H: ABH) on the immune system. First, we examined the cytokine-inducing activity of ABH on human peripheral mononuclear cells (PBMC). The results indicated that ABH induced expression of IL-12, a cytokine known to be a critical regulator of cellular immune responses. Flow cytometric analysis demonstrated the induction of IL-12 production by the CD14-positive cell population, consisting of monocytes/macrophages (Mo/Mphi). Furthermore, the elimination of Mo/Mphi attenuated IL-12 production in PBMC. ABH-induced IL-12 production was inhibited by anti-CD14 and anti-TLR4 antibodies but not by anti-TLR2 antibody. The activity of ABH was not inhibited by polymyxin B, while the activity of lipopolysaccharide used as a reference was inhibited. Oral administration of ABH enhanced natural killer (NK) activity in the spleen. These findings suggest that ABH activated Mo/Mphi in a manner dependent on CD14/TLR4 and NK activity.

Journal Article↗

Which types of non-bleeding visible vessels in gastric peptic ulcers should be treated by endoscopic hemostasis?

BACKGROUND AND AIMS: Because non-bleeding visible vessels (NBVV) of gastric peptic ulcers have the potential to re-bleed, endoscopic hemostatic treatment may be necessary during the first emergency endoscopy. However, not all NBVV re-bleed, and endoscopic hemostasis sometimes causes fatal side-effects. Therefore, we have evaluated the risk of re-bleeding from various NBVV in gastric peptic ulcers to determine which types should be treated by endoscopy to prevent re-bleeding. METHODS: A total of 227 NBVV in 202 patients with gastric peptic ulcers that were endoscopically followed without endoscopic hemostatic procedures were classified by the following factors: vessel color, form, location of the NBVV in the ulcer crater, and location of the ulcer in the stomach. The re-bleeding rate was then analyzed for each type of NBVV. RESULTS: Significantly high rates of re-bleeding were observed in cases with white, protruded and peripheral NBVV. In particular, white NBVV located in the peripheral zone of the ulcer crater were frequent re-bleeding sources. The location of the ulcer in the stomach was not a statistically significant factor in determining re-bleeding rates. CONCLUSION: We found that white, protruded and peripherally located NBVV in gastric ulcers have a higher chance of re-bleeding if preventive endoscopic hemostatic procedures are not performed.

Chi-Square Distribution↗

White spot syndrome virus infection in cultured Penaeus vannamei (Boone) in Ecuador with emphasis on histopathology and ultrastructure.

Mortalities of cultured shrimp, Penaeus vannamei (Boone), induced by white spot syndrome virus (WSSV) have occurred in Ecuador since May 1999. Three epidemiological surveys in Ecuadorian farms were carried out and showed an apparent association between lower temperature and increased mortality rates in commercial ponds. Infected animals showed a reddish discolouration and lethargy and occasionally, white spots in the exoskeleton. Histopathological studies revealed that infected cells presented nuclear hypertrophy with eosinophilic to basophilic inclusions. In some cases, two other pathologies were observed: (a) lymphoid organ spheroids and (b) cells with pyknotic and karyorrhectic nuclei in the lymphoid organ, haematopoietic tissue, connective tissue, heart and antennal gland. Occasionally pyknotic cells were encapsulated without apparent injury to the adjacent tissue and without melanization. Transmission electron microscopy showed the presence of WSSV particles in the cytoplasm of cells with pyknotic nuclei in the stomach hypodermis. Viral structure and morphogenesis agreed with previous descriptions by other authors in WSSV-infected shrimp. Occasionally, two nucleocapsids within one envelope were present amongst single enveloped nucleocapsids. A long rod-shaped structure that could reach 2.4 microm in length was present in the nuclei of some infected cells.

Animals↗

Sediment remediation for ecosystem in eutrophic lakes.

The remediation method--namely, a hybrid system combined with DAF and CRM--is studied in this paper for the size reduction of aqua-ecological circulation and for the elution control in lakes. Results show that two effects on water quality purification, the sediment washout effect and the elution control effect, can be induced by this system, and the biota inhabiting the lake is therefore shifted into an oligotrophic aspect, from blue algae to green algae and/or diatoms.

Ecology↗

A putative plant homolog of the yeast beta-1,3-glucan synthase subunit FKS1 from cotton (Gossypium hirsutum L.) fibers.

A novel plant gene CFL1 was cloned from cotton (Gossypium hirsutum L.) fibers by expressed sequence tag (EST) database searching and 5'-RACE (rapid amplification of cDNA ends). This gene shows sequence homology with FKS1 which has been identified as the putative catalytic subunit of the yeast beta-1,3-glucan synthase. It encodes a protein (CFL1p) of 219 kDa with 13 deduced transmembrane helices and 2 large hydrophilic domains, one of which is at the N-terminus and the other in the internal region of the polypeptide. CFL1 displays 21% identity and 41% similarity to FKS1 at the amino acid level over its entire length, with 31% identity and 52% similarity for the hydrophilic central domain. Using RNA and protein blot analysis, CFL1 was found to be expressed at higher levels in cotton fibers during primary wall development. CFL1 also had a strong expression in young roots. Using a calmodulin (CaM)-gel overlay assay, the hydrophilic N-terminal domain of CFL1p was shown to bind to CaM, while the hydrophilic central domain did not. A putative CaM-binding domain, 16 amino acids long, was predicted in the hydrophilic N-terminal domain. Moreover, a product-entrapment assay demonstrated that a protein associated with an in vitro-synthesized callose pellet could be labeled by anti-CFL1 antibodies. Our finding suggests that CFL1 is a putative plant homolog of the yeast beta-1,3-glucan synthase subunit FKS1 and could be involved in callose synthesis.

Calmodulin-Binding Proteins↗

[Epidemiological survey for hemolytic streptococci isolated from children in Tokyo].

During the 20-year period between 1979-1998, a total of 4,176 strains of hemolytic streptococci have been isolated from 20,118 healthy primary school children and little children in Tokyo Metropolitan (Tokubetsuku, Tama and Tosho). Culture of throat swabs every November and the following February during the 20-year period were made and serological grouping and typing for isolates were done by T agglutination method. The results were as follows. 1) Serological group of hemolytic streptococci isolated from children were 3,188 strains (76.3%) for isolates of group A out of total strains of 4,176, 569 strains (13.6%) for isolates group B, 63 strains (1.5%) for isolates of group C and 356 strains (8.5%) for isolates of group G. 2) The most dominant was T12 during 1979-1998, and other relatively frequent serotypes were T28, T1, T4, T6 in that order. These ranks of and the main epidemic serotypes showed a similar trend in the 3 areas. 3) The isolation rates of group A streptococci were 15.9% in Tokubetsuku, 17.1% in Tama and 14.9% in Tosho. The average of 3 areas were 15.8%. 4) The epidemic cases seemed to be caused by group A streptococci were 20 cases, their isolated serotype were 7 cases by T28, 5 cases by T12, 4 cases by T6, 2 cases by T4, each 1 case by T1 and T25. 5) A total of 2,927 strains of group A streptococci were examined for drug sensitivity. All strains were sensitive to beta-lactam group of antibiotics (benzylpenicillin and cephaloridine). Resistant (MIC > or = 25 micrograms/ml) to TC, CP and EM etc. were 740 strains (25.3%) in this study. The incidence of resistant strains were to TC 493 strains (66.6%) out of 740 strains, 81 strains (10.9%) for TC.CP, 72 strains (9.7%) for EM and 66 strains (8.9%) for TC.CP.EM.OL.LCM. TC resistant strains have not varied much through the whole period, but CP and EM resistant strains were very variable by year. Many resistant strains to TC were T4, to EM and multiple drug resistant were T12. 6) The rates of isolates of the same type of group A streptococci in school child individual during for the tests taken twice a year were 12.3%, indicating group A streptococci, according to the duration of the carrier state, seems to be a short period.

Child↗

Role of cellulose-binding domain of exocellulase I from white rot basidiomycete Irpex lacteus.

The core fragment (designated P-42), devoid of the cellulose-binding domain (CBD) in the C-terminus and prepared from Irpex lacteus exocellulase I (Ex-1), was isolated by limited proteolysis using papain. Both the hydrolytic activity and binding ability of the isolated P-42 toward insoluble cellulose were lower than those of the native Ex-1, whereas Ex-1 and P-42 showed similar hydrolytic activities toward soluble substrates. These results indicate that the CBD of I. lacteus Ex-1 is the important domain which could enhance hydrolytic activity and binding ability of the enzyme toward insoluble cellulose. In addition, the isolated P-42 was different from the native Ex-1 in terms of enzymatic properties such as pH and temperature stabilities. These differences in stability, with regard to pH and temperature, between P-42 and the native Ex-1 are probably due to the O-linked sugar chains existing in the linker region.

Journal Article↗

Purification and properties of thiosulfate dehydrogenase from Acidithiobacillus thiooxidans JCM7814.

A key enzyme of the thiosulfate oxidation pathway in Acidithiobacillus thiooxidans JCM7814 was investigated. As a result of assaying the enzymatic activities of thiosulfate dehydrogenase, rhodanese, and thiosulfate reductase at 5.5 of intracellular pH, the activity of thiosulfate dehydrogenase was measured as the key enzyme. The thiosulfate dehydrogenase of A. thiooxidans JCM7814 was purified using three chromatographies. The purified sample was electrophoretically homogeneous. The molecular mass of the enzyme was 27.9 kDa and it was a monomer. This enzyme had cytochrome c. The optimum pH and temperature of this enzyme were 3.5 and 35 degrees C. The enzyme was stable in the pH range from 5 to 7, and it was stable up to 45 degrees C. The isoelectric point of the enzyme was 8.9. This enzyme reacted with thiosulfate as a substrate. The Km was 0.81 mM.

Acidithiobacillus thiooxidans↗

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging of the brain. Technique for suppression of enhancing venous signal.

PURPOSE: Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging (BB-FSE) was performed to suppress enhancing venous signal and flow artifacts in the brain without sacrificing the T1-weighted imaging contrast. MATERIAL AND METHODS: Twenty-five MR imaging sections (17 transverse and 8 coronal images) in 15 patients with various brain diseases were obtained by contrast-enhanced T1-weighted SE and BB-FSE images. RESULTS: In contrast-enhanced T1-weighted BB-FSE images, venous signal was significantly less and T1-weighted contrast of the brain was more evident. No differences in flow artifacts were found between the two imaging techniques. The interobserver agreements were good for the venous signal and flow artifacts using both techniques. CONCLUSION: Contrast-enhanced T1-weighted BB-FSE imaging reduced the venous signal in the brain with maintaining T1-weighted contrast. This novel MR technique can be used when the suppression of enhancing venous signal is expected to improve the depiction of enhancing lesions in the brain.

Adult↗

[Usefulness of multiphase helical CT in the diagnosis of pituitary microadenoma].

The purpose of this study was to determine the value of multiphase helical CT (MHCT) in the diagnosis of pituitary microadenoma. Twenty-two patients with clinically suspected microadenoma were examined. Coronal pre-contrast CT was initially carried out. Three series of helical scanning using 1-mm collimation, 1-mm/s table speed, and 1-mm interval reconstruction covering the entire pituitary gland were performed with an intravenous injection of contrast medium. Immediately after MHCT, delayed CECT was performed. Twenty microadenomas (3-10 mm, mean: 5.5 mm) were surgically confirmed. MHCT could depict all 20 tumors, while pre-contrast CT and delayed CECT showed 4 and 12 of 20 tumors, respectively. MHCT was useful in the diagnosis of pituitary microadenoma owing to its high spatial resolution and extensive coverage.

Adenoma↗