Search PubMed⌕ Search

Biomedical subjects

Y Watanabe

Publications and source records attributed to Y Watanabe.

At least 37 records · Page 2Linked to original sources
PubMed2005

Levofloxacin- versus metronidazole-based rescue therapy for H. pylori infection in Japan.

BACKGROUND: The ideal second-line treatment regimens for Helicobacter pylori infection may differ between the areas, countries and races. AIM: The aim was to confirm which was the better regimen for second-line therapy after treatment failure with a standard triple therapy in Japan, a high dosage of levofloxacin- or metronidazole-based therapy. PATIENTS: Sixty outpatients with persistent H. pylori infection after a standard triple therapy were enrolled in this prospective, open-label and randomised trial. METHODS: The subjects were randomly administered levofloxacin (300 mg b.d.)- or metronidazole (500 mg b.d.)-based therapy with lansoprazole (30 mg b.d.) and amoxicillin (1000 mg b.d.) for 7 days, and the cure rates and side effects were analysed. Antimicrobial susceptibility was also examined before second-line therapy using the E-test. RESULTS: Good compliance was obtained without severe side effects in both the groups except for two patients. The cure rates, expressed as intention-to-treat and per-protocol analyses, respectively, were 70.0 and 72.4% in the levofloxacin group, and 96.7 and 100% in the metronidazole group. Each regimen often overcame even clarithromycin-resistant strains. CONCLUSION: Metronidazole-based triple therapy is recommended as second-line therapy in Japan, and levofloxacin-based therapy can be an alternative treatment option.

Adult↗
PubMed2005

Reduction of ferricytochrome c by tyrosyltyrosylphenylalanine.

Cytochrome c (cyt c) was reduced by a tyrosine-containing peptide, tyrosyltyrosylphenylalanine (TyrTyrPhe), at pH 6.0-8.0, while tyrosinol or tyrosyltyrosine (TyrTyr) could not reduce cyt c effectively under the same condition. Cyt c was reduced at high peptide concentration, whereas the reaction did not occur effectively at low concentration. The reaction rate varied with time owing to a decrease in the TyrTyrPhe concentration and the production of tyrosine derivatives during the reaction. The initial rate constants were 2.4 x 10(-4) and 8.1 x 10(-4) s(-1) at pH 7.0 and 8.0, respectively, for the reaction with 1.0 mM TyrTyrPhe in 10 mM phosphate buffer at 15 degrees C. The reciprocal initial rate constant (1/k(int)) increased linearly against the reciprocal peptide concentration and against the linear proton concentration, whereas logk(int) decreased linearly against the root of the ionic strength. These results show that deprotonated (TyrTyrPhe)(-), presumably deprotonated at a tyrosine site, reduces cyt c by formation of an electrostatic complex. No significant difference in the reaction rate was observed between the reaction under nitrogen and oxygen atmospheres. From the matrix-assisted laser desorption ionization time-of-flight mass spectra of the reaction products, formation of a quinone and other tyrosine derivatives of the peptide was supported. These products should have been produced from a tyrosyl radical. We interpret the results that a cyt c(ox)/(TyrTyrPhe)(-)right harpoon over left harpooncyt c(red)/(TyrTyrPhe)(*) equilibrium is formed, which is usually shifted to the left. This equilibrium may shift to the right by reaction of the produced tyrosyl radical with the tyrosine sites of unreacted TyrTyrPhe peptides.

Animals↗
PubMed2005

Opportunity of detecting pre-hypertension: worldwide data on blood pressure overswinging.

Overswinging or CHAT (brief for Circadian Hyper-Amplitude-Tension), that is an excessive circadian variation in blood pressure (BP), has been associated with a large increase in cardiovascular disease risk, present even in the absence of an elevated BP itself. This usually asymptomatic condition is usually overlooked by current practice based on spot-checks, because to be diagnosed, measurements need to be taken around-the-clock, preferably for 7 days at the outset. Once diagnosed, however, a usual circadian BP pattern can be restored by means of certain non-pharmacologic or pharmacologic interventions timed appropriately. Thereby, it is possible to reduce the risk of cardiovascular morbidity and mortality, cerebral ischemic events and nephropathy in particular. For the preparation of guidelines regarding the diagnosis of BP disorders and for the institution of primary as well as secondary preventive measures, it is important to know what the incidence of CHAT is on a global basis. We found 191 cases of CHAT among 1602 mostly 7-day/24-h BP profiles, obtained from several centers in different countries participating in an ongoing project on the BIOsphere and the COSmos (BIOCOS). CHAT incidence is about the same between men and women, but it is diagnosed more often among patients with borderline hypertension or with glucose intolerance. It is also more common among MESOR-hypertensive than among MESOR-normotensive individuals. Priority should be given to the development of an unobtrusive and affordable device to automatically monitor BP and to analyze the data as-one-goes, so that cardiovascular disease risk can be prevented.

Adult↗
PubMed2005

Colonic carcinoma resembling submucosal tumor: report of a case and review of the literature.

Submucosal tumor-like colorectal carcinoma, most of whose surface is covered with normal mucosa, is very rare. We report a case of colonic carcinoma resembling submucosal tumor. A 54-yr-old man visited our institution for an evaluation of a positive fecal occult blood test. Colonoscopic examination revealed a small, mainly red polypoid lesion with a central deep ulceration and many white spots in the sigmoid colon. Indigocarmine staining demonstrated that the white spots were faint shallow depressions. Magnifying colonoscopic examination showed that the lesion surface, except for the ulceration and the depressions, was covered with normal mucosa. Although the tumor was small, we strongly suspected its malignancy due to a deep ulceration. As we could not excise it endoscopically, we performed sigmoidectomy. The lesion was 12 mm in size. Histologic examination revealed that the lesion was a moderately differentiated adenocarcinoma that was mainly covered with normal mucosa, that carcinoma was exposed only at the ulceration and the depressions on the surface, and that it had expanded to the muscularis propria. Together with considerations from the literature, this type of colorectal carcinoma is supposed to be invasive and surgical resection should be considered, no matter how small it may be.

Adenocarcinoma↗
PubMed2005

Effect of pre-coagulation on mitigating irreversible fouling during ultrafiltration of a surface water.

Membrane fouling can be divided into two types: reversible fouling and irreversible fouling. The former can be easily canceled by physical cleaning (e.g., backwashing) while the latter needs chemical cleaning to be mitigated. For more efficient use of membranes, the control of irreversible membrane fouling is of importance. In this study, the effectiveness of pre-coagulation/sedimentation on irreversible membrane fouling was investigated, based on the pilot-scale operation of the membrane unit installed at an existing water purification plant. The membrane employed was a low-pressure ultrafiltration (UF) membrane made of polysulfone and having a molecular weight cut-off of 750,000 daltons. Although pre-coagulation/ sedimentation significantly mitigated membrane fouling mainly through the reduction of reversible membrane fouling, the degree of irreversible fouling was not reduced by the pre-treatment. This was because the irreversible fouling observed during this study was mainly attributed to polysaccharides/protein like fractions of organic substances that cannot be efficiently removed by coagulation/sedimentation. Aluminium used as coagulant was thought to cause irreversible fouling to some extent but did not in the pilot operation, which could probable be explained by the fact that coagulation was conducted at relatively high pH (7.0) in this study.

Aluminum Oxide↗
PubMed2005

Performance of ultrafiltration membrane process combined with coagulation/sedimentation.

Effects of coagulation/sedimentation as a pre-treatment on the dead-end ultrafiltration (UF) membrane process were studied in terms of membrane fouling and removal efficiency of natural dissolved organic matter, using Chitose River water. Two types of experiment were carried out. One was a bench scale membrane filtration with jar-test and the other was membrane filtration pilot plant combined with the Jet Mixed Separator (JMS) as a pre-coagulation/sedimentation unit. In the bench scale experiment, the effects of coagulant dosage, pH and membrane operating pressure on the membrane fouling and removal efficiency of natural dissolved organic matter were investigated. In the pilot plant experiment, we also investigated the effect of pre-coagulation/sedimentation on the membrane fouling and the removal efficiency of natural dissolved organic matter. Coagulation/sedimentation prior to membrane filtration process controlled the membrane fouling and increased the removal efficiency of natural dissolved organic matter.

Colloids↗
PubMed2005

Baffled membrane bioreactor (BMBR) for advanced wastewater treatment: easy modification of existing MBRs for efficient nutrient removal.

In this study, a novel membrane bioreactor (MBR) in which nitrification and denitrification simultaneously proceed in a single reaction chamber is proposed for advanced municipal wastewater treatment. Anoxic/aerobic environments are alternatively created in the proposed MBR by inserting baffles inside the membrane chamber. The performance of the proposed baffled membrane bioreactor (BMBR) was examined at an existing municipal wastewater treatment facility based on long-term operation. Although the procedure was simple, insertion of the baffles actually created the alternative anoxic/aerobic environments in the chamber at a constant interval and showed a great improvement in the nutrient removal. The insertion did not cause any adverse effect on membrane permeability. In this study, almost complete elimination of NH4+-N was observed while around 8 mg/L of NO(3-)-N was detected in the treated water. The modification proposed in this study can immediately be applied to most existing MBRs and is highly recommended for more efficient wastewater treatment.

Ammonia↗
PubMed2004

Comparison of transgene expression mediated by several Fiber-modified adenovirus vectors in trophoblast cells.

The transfer of genes of interest is a useful method for studying placental biology. Recombinant adenovirus (Ad) vector is an efficient vector for transgene expression. An interaction between the fiber of Ad and the coxsackievirus and adenovirus receptor on the cell membrane is the first step in infection. We previously developed fiber-modified Ad vectors and showed that they improved transgene activity in several cell lines when compared to wild-type vector. In the present study, we examined the ability of three fiber-modified Ad vectors to transduce human choriocarcinoma cell lines (JEG-3, JAR and BeWo) and rat trophoblast cell lines (Rcho-1, TR-TBT 18d-1 and TR-TBT 18d-2). We compared the transgene efficacy of wild-type Ad-L2 vector, Ad-RGD(HI)-L2 vector containing an Arg-Gly-Asp motif, Ad-K7(C)-L2 vector containing a 7-tandem lysine motif, and Ad-RGD(HI)K7(C)-L2 vector containing both motifs in the fiber. We used the luciferase gene as a reporter gene. In the human and rodent trophoblast cell lines, Ad-RGD(HI)-L2 had the greatest infectious potential, followed by Ad-RGD(HI)K7(C)-L2, Ad-K7(C)-L2 and Ad-L2. Compared to the amount of luciferase produced by wild-type vector, Ad-RGD(HI)-L2 mediated 8.1-fold the amount of luciferase in JEG-3 cells, 13.5-fold in JAR cells, 76.8-fold in BeWo cells, 5.0-fold in Rcho-1, 19.4-fold in TR-TBT 18d-1 and 15.0-fold in TR-TBT 18d-2. These results indicate that Ad-RGD(HI) is a potential recombinant Ad vector for transgene expression in some trophoblast cell lines.

Adenoviridae↗
PubMed2004

Identification and mapping of cleistogamy genes in barley.

Cleistogamy is a closed type of flowering with ensured self-pollination and an important trait to study evolutionary development in flower organs, reproduction systems, gene flow, and disease control. Still, very limited information is available about the genetic control and regulatory mechanism of this trait in barley. In this work, from the eight crosses between cleistogamous and chasmogamous accessions, five crosses generated chasmogamous F1 plants and their F2 plants segregated as 3 chasmogamous:1 cleistogamous, whereas three crosses generated cleistogamous F1 plants, and their F2 plants segregated as 1 chasmogamous:3 cleistogamous. Although a single gene was responsible for the control of cleistogamy in these two groups of crosses, the direction of dominance was opposite, suggesting two genes, cly1 and Cly2, for the genetic control of cleistogamy in barley. Epistatic type of gene interaction between the two loci was detected. In the analysis of 99 recombinant inbred lines of 'Azumamugi' x 'Kanto Nakate Gold' and doubled haploid lines of 'Harrington' x 'Mikamo Golden', where in both crosses F1 was chasmogamous, the cly1 locus has been mapped on chromosome 2HL. Using the analysis of the F2 population of 'Misato Golden' and 'Satsuki Nijo' where F1 was cleistogamous, the Cly2 locus was mapped in the same region of chromosome 2HL. Because the cly1 and Cly2 loci were mapped in the same region in these three different mapping populations, it was concluded that the expression of cleistogamy is under the control of two tightly linked genes or different alleles of the same gene.

Chromosome Mapping↗
PubMed2004

Bowel movement frequency and risk of colorectal cancer in a large cohort study of Japanese men and women.

The relationship between bowel movement (BM) frequency and the risk of colorectal cancer was examined in a large cohort of 25 731 men and 37 198 women living in 24 communities in Japan. At enrolment, each participant completed a self-administrated questionnaire on BM frequency and laxative use. Incidence rate ratios (IRR) with 95% confidence intervals (CI) were estimated using Cox's proportional-hazard model. During the follow-up period (average length 7.6 years), 649 cases of colorectal cancer, including 429 cases of colon cancer, were identified. Among women, subjects who reported a BM every 2-3 days had the lowest risk of developing colorectal (IRR=0.71, 95% CI=0.52-0.97) and colon cancer (IRR=0.70, 95% CI=0.49-1.00), whereas those reporting a BM every 6 days or less had an increased risk of developing colorectal (IRR=2.47, 95% CI=1.01-6.01) and colon cancer (IRR=2.52, 95% CI=0.93-6.82) compared with those reporting >or=1 BM per day. A similar, but nonsignificant, association between the frequency of BM and cancer risk was observed in men. There was no association between colorectal or colon cancer risk and laxative use. Regulating BM frequency might therefore have a role in the prevention of colorectal cancer.

Adult↗
PubMed2004

Induction of hepatic metallothionein synthesis by endoplasmic reticulum stress in mice.

Metallothionein (MT) is a small sulfhydryl-rich protein whose levels are elevated by various inducers of organelle stresses, such as nuclear stress (cisplatin), mitochondrial stress (antimycin A, 2,4-dinitrophenol) and lysosomal stress (paraquat). Although abnormal folding of protein in the endoplasmic reticulum (ER) causes ER stress, induction of MT synthesis by ER stress has never been investigated. In this study, we examined the induction of MT by an inducer of ER stress, tunicamycin (Tun), which induces ER stress by inhibiting N-linked glycosylation of protein in the ER. Administration of Tun (0.5-1.5 mg/kg, sc) increased hepatic MT levels in C57BL/6J mice (3.1-fold). The maximal increase in hepatic MT was observed 48-96 h after the administration of Tun (1.0 mg/kg). Expressions of MT-I, II and glucose-regulated protein 78 (Bip/GRP78), which is a molecular chaperone induced by ER stress, mRNA were also detected by administration of Tun. Thapsigargin (Thap), a generator of ER stress by inhibiting ER Ca(2+)-ATPase, also increased both hepatic MT levels and expression of MT-I and -II mRNA. The level of expression of Bip/GRP78 mRNA induced by Tun administration in MT-null mice was greater than that in wild-type mice. Taken together, these findings suggest that inhibitors of ER are potent inducers of MT.

Animals↗
PubMed2004

Cell kinetic balance in gastric mucosa with intestinal metaplasia after Helicobacter pylori eradication: 2-year follow-up study.

BACKGROUND: Proliferation and apoptosis events are altered in Helicobacter pylori infection. However, whether H. pylori eradication has an effect on the disturbed kinetics in metaplastic mucosa has not been well elucidated. AIM: To investigate the effect of eradication on the gastric cell kinetics. SUBJECTS AND METHODS: Initially, biopsies were obtained from 74 H. pylori-infected subjects and repeated 12 and 24 months after eradication. Biopsies were immunohistochemically stained for apoptosis by single-stranded DNA, for proliferation by Ki-67 antibodies and for intestinal metaplasia MUC2, MUC5AC, MUC6 and CD10. RESULTS: While antral apoptosis in intestinal metaplasia was significantly lower than in non-intestinal metaplasia, proliferation was significantly higher (greater and lesser curvatures, P < 0.05, respectively). This resulted in a significantly lower apoptosis/proliferation ratio in intestinal metaplasia than in non-intestinal metaplasia (antrum greater and lesser curvatures and corpus greater curvature, P < 0.05). After successful eradication, apoptosis and proliferation decreased in both intestinal metaplasia and non-intestinal metaplasia. The pattern of reduction of apoptosis and proliferation differed in these two groups. However, in the corpus, the reduction resulted in a significant increase in the apoptosis/proliferation ratio in both. CONCLUSION: Proliferation and apoptosis are unevenly and disproportionately altered in H. pylori infection leading to an imbalance in cell kinetics. Eradication of the organism improves the balance and may possibly play a role in the prevention of malignancy transformation in the metaplastic mucosa.

Adult↗
PubMed2004

The results of therapy for bilateral multiple primary lung cancers: 30 years experience in a single centre.

AIMS: This study reviews our 30 years experience in the clinical assessment and surgical management of bilateral multiple primary lung cancer (BMPLC). METHODS: Between January 1973 and December 2001, 1906 patients with primary lung cancer underwent surgical resection in Kanazawa University Hospital. Thirty-seven patients (1.9%) who had developed a BMPLC using the criteria of Martini and Antakli. RESULTS: Eighteen patients had synchronous lesions, and 18 patients had metachronous lesions. One patient had synchronous and metachronous lesions. Overall 10-year survival was 56%. The actuarial 5-year survival for bilateral synchronous cancers was 69%, median survival (MST) 90 months (range 8-153 months), and 10-year survival was 47%. The actuarial 5-year survival for second metachronous cancers was 51%, with an MST of 114 months (range 6-192 months). CONCLUSION: Aggressive surgical therapy is effective in patients with a bilateral MPLC if they satisfy the usual criteria of operability. The surgical methods that preserve healthy lung tissue such as sleeve resection and limited resection must be selected in compliance with cancer characters.

Adult↗
PubMed2004

Analysis of ultrasonic attenuation in particle-reinforced plastics by a differential scheme.

Attenuation of ultrasonic longitudinal waves in some particle-reinforced polymer composites is studied theoretically by a micromechanical model based on a differential (incremental) scheme. A set of differential equations is established by which the attenuation spectrum of the composite can be computed from the known properties of viscoelastic matrix and elastic particles. For a composite reinforced with glass particles with radius 0.15 mm, the proposed scheme is shown to predict the attenuation in better agreement with the foregoing experimental results than the previous simplistic independent scattering model. Based on this scheme, the dependence of the longitudinal attenuation spectrum of a particulate polymer composite on the wavelength-to-particle radius ratio and the particle volume fraction is examined in detail. It is then shown theoretically that the attenuation of the composite decreases monotonically with the particle volume fraction when the particle radius is sufficiently small compared to the incident wavelength, while it shows non-monotonic particle-fraction dependence when the ratio of the particle radius to the wavelength is larger. To examine this theoretical finding from an experimental point of view, the longitudinal attenuation in a glass-particle-reinforced polyester composite with particle radius 0.0225 mm is measured for different particle volume fractions. The measured attenuation characteristics are shown to support the qualitative features of the theoretical prediction.

Journal Article↗
PubMed2004

A prospective study of body size and colon cancer mortality in Japan: The JACC Study.

OBJECTIVE: To determine whether body size measurements are risk factors for colon cancer death among the Japanese. DESIGN AND SUBJECTS: A nationwide prospective study, the Japan Collaborative Cohort (JACC) Study from 1988 to 1999. The present analysis included 43 171 men and 58 775 women aged 40-79 y who respond to a questionnaire on current weight and height, weight around 20 y of age, and other lifestyle factors. Body mass index (BMI) at baseline and 20 y of age (B-BMI and 20-BMI, respectively) were calculated. RESULTS: We identified 127 deaths from colon cancer during the follow-up of 424 698 person-years among men and 122 deaths during the follow-up of 591 787 person-years among women. After adjustments for the lifestyle factors known to modify the risk of colon cancer, weight at baseline showed a significant positive association in women, while no such association was seen in men. There was also a significant trend of increasing risk with the increase in B-BMI among women. Women with B-BMI >/=28 kg/m(2) had a relative risk (RR) of 3.41 (95% confidence interval (CI): 1.44-8.06) compared with those with BMI of 20-<22 kg/m(2). 20-BMI also presented the same trend of increasing risk as B-BMI. Women with 20-BMI of <22 and B-BMI of >26 kg/m(2), that is, excessive BMI gain, had a high RR of 3.41 (95% CI 1.29-9.02) compared with those with 20-BMI of <22 and B-BMI of <22 kg/m(2). There were no corresponding trends of colon cancer risk for B-BMI, 20-BMI, or BMI change among men. CONCLUSIONS: These study data suggest that obesity and excessive weight gain are associated with the risk of colon cancer death in Japanese women but no such relationship was found in Japanese men.

Adult↗
PubMed2004

Visualization of pancreaticobiliary reflux in anomalous pancreaticobiliary junction by secretin-stimulated dynamic magnetic resonance cholangiopancreatography.

PURPOSE: To assess the utility of secretin-stimulated dynamic MR cholangiopancreatography (MRCP) for the visualization of pancreaticobiliary reflux in patients with anomalous pancreaticobiliary junction (PBJ). MATERIAL AND METHODS: Ten controls and seven patients diagnosed as having anomalous PBJ were prospectively examined by dynamic MRCP after secretin injection using a breath-hold, single-shot turbo spin-echo T2-weighted sequence. The optimal MRCP section was repeated 35 times at approx. 10-second interval after secretin injection; the acquisition time was 4 s per image. The signal intensity (SI) changes of the extrahepatic and intrahepatic bile ducts, presence or absence of intraluminal signal void, caliber change of the bile duct, duodenal filling, and peak time of the SI ratio of the extrahepatic bile duct after secretin injection were compared between the controls and patients. RESULTS: In the controls, the extrahepatic and intrahepatic bile ducts showed neither enhancement nor caliber change over the observation period, providing no apparent peak time. Of the seven patients, the extrahepatic bile duct showed retrograde enhancement and sequential delay in occurrence of the peak time from its distal third to its proximal third (n = 6) with a signal void in its distal part (n =4); its caliber increased subsequently to pancreatic secretion (n = 5); the intrahepatic bile ducts showed a slight enhancement following SI increase of the proximal extrahepatic bile duct (n = 6); duodenal filling grade tended to be lower in the patients than volunteers (P<.005). CONCLUSION: In patients with anomalous PBJ pancreaticobiliary reflux were demonstrated by dynamic secretin-stimulated MRCP.

Adolescent↗
PubMed2004

Abdominal stapled side-to-end anastomosis (Baker type) in low and high anterior resection: experiences and results in 69 consecutive patients at a regional general hospital in Japan.

OBJECTIVE: The technique of transanally introducing a circular stapled device to accomplish colorectal anastomoses has been widely used. However, the widespread popularity of this technique may have created the potential of anal sphincter injury during transanal insertion of the anastomosing stapler. Thus, to avoid the risk of anal sphincter injury during anal manipulation, we have been performing an abdominal approach, namely abdominal stapled side-to-end anastomosis (ASSEA) using a Purstring and premium curved EEA stapler in low and high anterior resection. This study will present our experience and results of consecutive resections. METHODS: ASSEA following a resection of the rectum and sigmoid colon for carcinomas was consecutively performed between October 1998 and May 2002. Age, sex, pre-operative anal function, the TNM classification by the UICC rules, operative methods, postoperative morbidity, mortality, anal function and bowel frequency were evaluated. RESULTS: Sixty-nine consecutive patients underwent a resection of the rectum and sigmoid colon with ASSEA. There were three (4.3%) clinical anastomotic leakages in the cases studied. Anastomoses that were located above the peritoneal reflection leaked in one (2.5%) of 40 cases, while anastomoses below the peritoneal reflection leaked in two (6.9%) of 29 cases. A diverting stoma was performed in five (17%) of the 29 cases with low anastomosis. Postoperative anal function was stable without soiling or faecal leakage and bowel frequency two months after surgery was less than four times in all 61 patients. There was no postoperative mortality related to the anastomosis. CONCLUSIONS: Abdominal stapled side-to-end anastomosis (Baker type) was found to be a safe and relatively easy method in both low and high anterior resection in association with a good quality of life.

Abdomen↗