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T Yamada

Publications and source records attributed to T Yamada.

At least 37 records · Page 2Linked to original sources
PubMed2006

A new method of diagnosing gastric intestinal metaplasia: narrow-band imaging with magnifying endoscopy.

BACKGROUND AND STUDY AIMS: With endoscopy, there is a high rate of interobserver variability in the identification of gastric intestinal metaplasia, and the endoscopic findings correlate poorly with the histological findings. Previous studies by our group investigating the use of a narrow-band imaging system with magnifying endoscopy (NBI-ME) in the gastric mucosa suggested that the appearance of a light blue crest (LBC) on the epithelial surface may be a distinctive endoscopic finding associated with the presence of intestinal metaplasia. The aim of the present study was to clarify the value of NBI-ME for diagnosing gastric intestinal metaplasia. PATIENTS AND METHODS: The LBC was defined as a fine, blue-white line on the crests of the epithelial surface/gyri. To investigate the histology underlying the appearance of LBC, 44 biopsy specimens were obtained from regions containing LBC and 44 from non-LBC mucosa in 34 patients with atrophic gastritis. Three endoscopists then carried out NBI-ME in 107 consecutive patients to validate the diagnostic accuracy of the novel endoscopic technique. The degree of correlation between the LBC grading and the histological parameters of intestinal metaplasia was then assessed. RESULTS: The LBC grading correlated with cells that were positive for CD10 ( P = 0.0001) and Alcian blue ( P = 0.036). The appearance of LBC correlated with histological evidence of intestinal metaplasia with a sensitivity of 89 % (95 % CI, 83 - 96 %), a specificity of 93 % (95 % CI, 88 - 97 %), a positive predictive value of 91 % (95 % CI, 85 - 96 %), a negative predictive value of 92 % (95 % CI, 87 - 97 %), and an accuracy of 91 % (95 % CI, 88 - 95 %). CONCLUSIONS: In narrow-band imaging with magnifying endoscopy, observation of a light blue crest on the epithelial surface in the gastric mucosa is a highly accurate sign of the presence of histological intestinal metaplasia.

Adult↗
PubMed2006

Endoscopic ultrasound-guided fine-needle aspiration biopsy for lymphadenopathy of unknown origin.

BACKGROUND AND STUDY AIMS: The diagnosis of mediastinal and intra-abdominal lymphadenopathy is sometimes difficult, especially in patients who have no other primary lesions. Lymphoma is one of the main causes of this condition. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and accurate diagnostic procedure for lesions surrounding the gastrointestinal tract. However, diagnosing lymphoma using the EUS-FNA technique remains a diagnostic challenge, due to limitations in the amount of material sampled. The aim of the present study was to evaluate the yield of EUS-FNA biopsy (EUS-FNAB) using a large-gauge needle in patients with mediastinal and intra-abdominal lymphadenopathy of unknown origin, especially in relation to subclassification of the lymphomas. PATIENTS AND METHODS: Consecutive patients with mediastinal and intra-abdominal lymphadenopathy of unknown origin who were referred between October 2003 and March 2005 were enrolled in the study. EUS-FNAB was carried out using a 19-gauge needle, passing through the esophageal, gastric, and duodenal walls. Pathological diagnoses were made on the basis of histological findings, including immunopathological staining. RESULTS: A total of 104 patients were included in the study. The locations of the lymph nodes were mediastinal in 50 patients, intra-abdominal in 48 patients, and both mediastinal and intra-abdominal in six patients. The diagnoses made using EUS-FNAB were lymphoma (n = 48), metastasis (n = 16), and benign/reactive (n = 40). The overall accuracy of EUS-FNAB for unknown lymphadenopathy was 98 %, and it was possible to classify the lymphomas in accordance with the World Health Organization classifications in 88 % of cases. No serious complications occurred with the procedure. CONCLUSIONS: Open thoracic surgery, laparotomy, and other invasive diagnostic procedures such as mediastinoscopy and laparoscopy can now be avoided, as EUS-FNAB is potentially a safe and accurate tool for diagnosing unknown lymphadenopathy, including lymphoma.

Adult↗
PubMed2006

Exploration of genes showing intramuscular fat deposition-associated expression changes in musculus longissimus muscle.

Marbling, as defined by the amount of intramuscular fat, is an economically important trait in beef cattle. Intramuscular fat deposition is postulated to arise mainly from a series of adipogenic events in intramuscular adipocyte-lineage cells and in the physiological or anatomical milieux surrounding them. This study was designed to investigate gene-expression patterns associated with fat deposition in musculus longissimus muscle, including adipocyte-lineage cells and part of the milieux. Differential-display PCR (ddPCR) was used to examine expression differences between low-marbled and high-marbled steer groups at 8, 10, 12 and 14 months of age, encompassing the time that marbling starts to appear. Seventy-four of 2114 total bands on ddPCR gel-bands were significant (P < 0.05) for the group effect, the interaction effect between group and age, or both the group and the interaction effects. Sequence analysis of 72 of these bands revealed 77 genes, including 35 annotated genes and 42 novel sequences. Among the 35 annotated genes, 6 (BTG2, PDHB, SORBS1, TRDN, TTN and MGP) have been related to changes in intramuscular fat deposition, possibly by exerting effects on adipocyte-lineage cells or on the milieux surrounding them.

Adipose Tissue↗
PubMed2006

Immunohistochemical detection of ubiquitin-positive intracytoplasmic eosinophilic inclusion bodies in diffuse alveolar damage.

AIMS: To clarify the relationship between ubiquitin-positive pneumocytes and intracytoplasmic eosinophilic inclusion bodies (IB) in patients who died of diffuse alveolar damage (DAD). METHODS AND RESULTS: Eighteen patients with DAD were studied, in whom hyaline membranes were present in one or more out of five sections from each lobe of the lungs and 15 patients with no DAD. Light microscopy revealed hyaline membrane in over 25% of lobes from 18 patients with DAD. The cytoplasm of pneumocytes from six of 18 cases of DAD contained IB. Immunohistochemically, all IBs were characteristically positive for both ubiquitin (Ub) and cytokeratin KL-1. Cytoplasmic granules were also Ub+ in four cases of DAD without IB. IB+ or Ub+ pneumocytes were undetectable in non-DAD patients. We evaluated DAD severity based on hyaline membrane formation; the mean score in DAD with IB (3.60; n = 6) was significantly higher than that in Ub- (2.92; n = 8). Ub+ pneumocytes were found with or without IB among those cases with high DAD scores. CONCLUSIONS: These findings suggest that disordered proteolysis in the Ub-mediated proteasome system leads to the accumulation of abnormal ubiquitinated protein, which includes cytokeratin, in pneumocytes. This is the first report to suggest that Ub+ pneumocytes are associated with disease severity in patients with DAD.

Adolescent↗
PubMed2006

Infection dynamics of Neoheterobothrium hirame (Monogenea) on juvenile olive flounder, Paralichthys olivaceus (Temminck & Schlegel), in coastal waters of Japan.

A recent epidemic of the invasive monogenean Neoheterobothrium hirame is suspected to have caused the significant decline of the commercial catch of olive flounder, Paralichthys olivaceus, in Japan. To clarify the causal link between parasite invasion and host depletion, we monitored the infections of N. hirame on juvenile flounder for 2 years at two widely separate bays, Obama Bay, experiencing a devastating reduction in flounder catches, and Miyako Bay with a stable catch. Prevalence, mean intensity and abundance of developmental stages of N. hirame were compared between the bays and between fish year classes. Fishes captured at Obama Bay harboured three times more worms than those at Miyako Bay and had a significantly higher overall prevalence of infection. In addition, there was a negative correlation between parasite intensity and host condition factor at Obama Bay, suggesting a causal link between the N. hirame epidemic and the reduction of local flounder populations.

Animals↗
PubMed2006

Prognosis of patients who develop cervical lymph node recurrence following curative resection for thoracic esophageal cancer.

Patients with esophageal cancer often display relapse at cervical nodes after surgery, but their prognosis and a suitable therapy remains unknown. We retrospectively reviewed the records for 35 patients who underwent esophagectomy with lymphadenectomy who then displayed relapse at the cervical lymph nodes alone between 1985 and 2003 in order to observe the prognostic factors for such patients. Median survival time from the date of recurrence for all 35 patients was 12 months with 1-year, 2-year, 3-year and 5-year survival rate of 47.2%, 26.5%, 17.7% and 8.8%, respectively. With regard to the initial treatment against cervical node recurrence, 15 patients were treated by radiotherapy alone, eight by chemoradiotherapy, 11 by surgery and one by chemotherapy alone. Univariate analysis revealed that cervical node dissection at the prior esophagectomy (yes/no, P = 0.0178), time to recurrence (> 9 months or < 9 months, P = 0.0497) and the number of relapsed nodes (solitary/multiple, P = 0.0029) were significant prognostic factors. Among these factors, the number of relapsed nodes (solitary/multiple) was found to be the only significant prognostic factor with an odds ratio of 2.409 and 95% confidence interval of 1.033-5.619 by multivariate analysis. In conclusion, cervical node metastasis is generally considered to be distant organ metastasis. However, if it is a solitary node recurrence, substantial survival can be attained by appropriate loco-regional therapy.

Aged↗
PubMed2006

Preoperative chemotherapy for clinically node-positive patients with squamous cell carcinoma of the esophagus.

Lymph node metastasis is one of the strongest prognostic factors for patients with esophageal cancer. Whether neoadjuvant chemotherapy is effective for metastatic nodes and improves the prognosis of clinically node-positive patients is unknown. Seventy-seven patients with clinically node-positive esophageal cancer, who were given preoperative chemotherapy (5-fluorouracil, cisplatin and adriamycin) followed by surgery, were retrospectively analysed. The histological effectiveness of the chemotherapy against the main tumor in the resected specimen was correlated with nodal status and prognosis. Of the 77 patients, the histological effects in the main tumors were grade 3 in one patient (1.3%), grade 2 in 10 (13.0%), grade 1b in seven (9.1%), grade 1a in 50 (64.9%) and grade 0 in nine (11.7%). Eleven patients (14.3%) were found to be pathologically node-negative. The pathological stages were significantly earlier in responders (grades 3-1b) than in non-responders (grades 1a-0) (P = 0.0001). The responders showed a significantly lesser degree of lymph node metastasis (P = 0.0005), fewer metastatic nodes (2.2 +/- 3.1 vs. 12.0 +/- 20.5, P = 0.0482) and better survival (P = 0.002) than the non-responders. The most common failure pattern for the non-responders was lymphatic recurrence, with an incidence of 47.5% (28/59), while that for the responders was 16.7%. Responders to neoadjuvant chemotherapy show fewer metastatic nodes and better prognosis than non-responders. Neoadjuvant chemotherapy may offer clinical benefit to responders.

Antineoplastic Agents↗
PubMed2006

Influence of administration methods on the accumulation of ALA-induced Pp-IX in mouse tongue tumors.

OBJECTIVE: 5-Aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) has been used as a photosensitizer in photodynamic therapy (PDT) for oral cancer. This study investigates the optimal method of administrating ALA by analyzing PpIX fluorescence in tongue tumor tissue. METHODS: Protoporphyrin IX intensities in the mouse (C3H)-transplanted tongue cancer (NR-S1) were compared with those in normal tongue after intraperitoneal (i.p.), oral (p.o.) or topical administration of ALA. Tongues were sampled at various times after ALA administration. PpIX intensities were obtained from frozen sections of each sample by using a spectrophotometer. RESULTS: Protoporphyrin IX intensity in the tumor group peaked at 3 h after the i.p. and 5 h after the p.o. administration of ALA, and these levels were about twice as high as those in the normal group. Maximum PpIX accumulation in the tongue tumor tissue was seen at 5 h after p.o. administration of ALA. In contrast, the topical administration of 20% ALA cream was associated with the lowest PpIX accumulation in the tumor throughout the experiments. CONCLUSION: These results suggested that p.o. administration of ALA was the most effective method in ALA-PDT for oral cancer.

Administration, Oral↗
PubMed2006

Genomic structure of swine taste receptor family 1 member 3, TAS1R3, and its expression in tissues.

Taste receptor family 1 member 3, TAS1R3, is shown to be involved in sweet and umami tastes in mouse, and the nucleotide sequence of the gene has been reported in rat, gorilla, and human. Pigs are frequently used as models for human diseases, and are also considered to be source animals for xenotransplantation to humans due to their anatomical and physiological similarities to humans. Therefore, in the present study, the genomic structure of the swine TAS1R3 gene was determined, and TAS1R3 expression was studied in various swine tissues. The gene was shown to reside on swine chromosome 6q22-->q23, from which three types of mRNAs were generated: 3,752 bp derived from six exons in tongue, 3,704 bp from six exons and 3,630 bp from seven exons in testis. The 6 exons/5 introns were structurally similar to those of humans and mice, but the 7 exons/6 introns structure of TAS1R3 was first observed in swine. High expressions of TAS1R3 were revealed in tongue, kidney, and testis by real-time PCR. The expression profile of the tissues except for kidney was similar to that of mouse. When in situ hybridization using an RNA probe for TAS1R3 was performed on swine tongue and testis tissues, TAS1R3 expressions were revealed in tongue circumvallate papillae, fungiform papillae, mucosal epithelium, follicular B lymphocytes, lymphocytes in submucosal tissues of lingual tonsil, and spermatogenic cells. Using peripheral mature B lymphocytes, the expression of TAS1R3 in B lymphocytes was further confirmed by real-time PCR and sequencing of the real-time PCR product.

Animals↗
PubMed2006

[Assessment of surgery for stage IV non-small cell lung cancer].

We assessed the survival of surgery for stage IV non-small cell lung cancer. Forty-two patients were operated on lung cancer for stage IV from 1986 to 2005. Overall median survival time (MST) was 12.3 months and 5-year survival rate was 9.8%. There was significant difference in survival between pulmonary metastasis (pm2) and other sites metastasis (p<0.05). In pm2 patients there was significant difference between ipsilateral metastasis and contralateral metastasis (MST 21.9 months, 2-year survival rate 48.6%, 5-year survival rate 21.6% and MST 12.3 months, 2-year survival rate 0%) [p<0.05], and between complete resection and incomplete resection (MST 36 months, 2-year survival rate 64.8%, 5-year survival rate 28.8% and MST 12.3 months, 2-year survival rate 0%) [p<0.01]. In patients with brain metastasis, surgery of brain metastasis was better prognosis than radiation therapy (MST 12.5 months, 3-year survival rate 33.3% and MST 8.3 months, 2-year survival rate 0%) [NS].

Aged↗
PubMed2006

[A study of high-resolution computed tomography (HRCT) findings of resected small pulmonary nodules 2 cm or less in diameter with reference to the malignant nature].

To identify the characteristics of peripheral small lung mass lesions on high-resolution computed tomography (HRCT) and discriminate between malignant and benign, 223 mass lesions 2 cm or less resected surgically were evaluated about following points. 1) Density : 90.7% of lesions with mixed solid and ground-glass opacity (GGO) components were adenocarcinomas. Pure GGO lesions without scale-down between several months were all adenocarcinomas or atypical adenomatous hyperplasia (AAH). Thereby, patients with these findings are good candidates for surgical resection. 2) Spicular or pleural indentation :75.2% (88 of 117 cases) of adenocarcinomas and all squamous cell carcinomas (18 cases) showed these findings, but 26.6% (41 of 154 cases) of positive cases were benign lesion (non-specific inflammation, mycobacterisis, and so on). Accordingly, they are not peculiar to malignancy. 3) Satellite lesion : all lesions with this one showed benign, therefore it was thought that this finding could exclude malignant lesion. Thus, recognition of certain characteristics at HRCT can be helpful in discrimination between small malignant mass and benign mass.

Adenocarcinoma↗
PubMed2006

Comparison of force-time parameters and EMG in static explosive gripping by various exertion conditions: muscle fatigue state and submaximal exertion.

AIM: The purpose of this study was to compare the exertion and electromyography (EMG) properties during the developmental phase (DFmax) in static explosive grip (SEG), rapid submaximal exertion grip, namely fake SEG exertion (FAKE), and SEG in a muscle fatigue state. METHODS: Thirty healthy males and females performed the SEG and FAKE exertions (50% and 75% of peak value as a target value). Then, they performed sustained repeated rhythmic grip for 6 min (30 times x min(-1)), and SEG after 1-min, 4-min, and 7-min (SEG after the exertion). EMG was measured concurrently to compare with the muscle activation property during each grip exertion. Eight force-time parameters evaluating the DFmax in addition to the peak value were selected. RESULTS: The peak value significantly decreased, and the mean power spectrum density shifted to the low-wave in SEG after the exertion as compared with before. Therefore, SEG after the exertion was judged to be a muscle fatigue state. In addition, because the frequency properties in each exertion differed, the muscle activation properties during their DFmaxs were considered to differ. From the comparison between SEG before and after the exertion and FAKE, it is suggested that the time of reaching the peak value and the relative muscle strength when reaching an inflection point are not useful as parameters to evaluate the explosive muscle function during SEG. CONCLUSIONS: The maximal increasing volume during the DFmax and integrated area until 0.25 and 0.5 s could discriminate a difference of the DFmaxs according to each exertion and they are useful parameters.

Adult↗
PubMed2005

High-temperature and high-pressure in situ SCC device for synchrotron radiation diffraction experiments and application using an austenitic stainless steel.

Suppressing the stress corrosion cracking (SCC) by reducing the carbon content in austenitic stainless steels is apparently not effective on core shrouds used in boiling water reactors in Japan: trans-granular cracking was found in the shrouds. To clarify the mechanism of the cracking, in situ stress measurements on specimens under stretched conditions in hot water have been attempted in the present study. An in situ device for diffraction measurements at synchrotron radiation facilities has been developed, and in situ experiments have been carried out at SPring-8. The SUS316L steel specimen was solution heat-treated, surface-ground and then placed in the in situ device. Sapphire windows were used for the light path in the device. A sufficient diffracted beam intensity was obtained through two sapphire windows and water. The side-inclination method was used for measuring the stress exerted on the specimen. A 2theta-sin2psi plot showed that a tensile stress was induced. The measured stress value is considered to be the summation of stresses owing to pre-straining, in situ loading and residual stress owing to surface grinding.

Elasticity↗
PubMed2005

Molecular cloning and genetic mapping of perennial ryegrass casein protein kinase 2 alpha-subunit genes.

The alpha-subunit of the casein protein kinase CK2 has been implicated in both light-regulated and circadian rhythm-controlled plant gene expression, including control of the flowering time. Two putative CK2alpha genes of perennial ryegrass (Lolium perenne L.) have been obtained from a cDNA library constructed with mRNA isolated from cold-acclimated crown tissue. The genomic organisation of the two genes was determined by Southern hybridisation analysis. Primer designs to the Lpck2a-1 and Lpck2a-2 cDNA sequences permitted the amplification of genomic products containing large intron sequences. Amplicon sequence analysis detected single nucleotide polymorphisms (SNPs) within the p150/112 reference mapping population. Validated SNPs, within diagnostic restriction enzyme sites, were used to design cleaved amplified polymorphic sequence (CAPS) assays. The Lpck2a-1 CAPS marker was assigned to perennial ryegrass linkage group (LG) 4 and the Lpck2a-2 CAPS marker was assigned to LG2. The location of the Lpck2a-1 gene locus supports the previous conclusion of conserved synteny between perennial ryegrass LG4, the Triticeae homoeologous group 5L chromosomes and the corresponding segment of rice chromosome 3. Allelic variation at the Lpck2a-1 and Lpck2a-2 gene loci was correlated with phenotypic variation for heading date and winter survival, respectively. SNP polymorphism may be used for the further study of the role of CK2alpha genes in the initiation of reproductive development and winter hardiness in grasses.

Amino Acid Sequence↗
PubMed2005

The role of log-normal dynamics in the evolution of biochemical pathways.

The study of the scale-free topology in non-biological and biological networks and the dynamics that can explain this fascinating property of complex systems have captured the attention of the scientific community in the last years. Here, we analyze the biochemical pathways of three organisms (Methanococcus jannaschii, Escherichia coli, Saccharomyces cerevisiae) which are representatives of the main kingdoms Archaea, Bacteria and Eukaryotes during the course of the biological evolution. We can consider two complementary representations of the biochemical pathways: the enzymes network and the chemical compounds network. In this article, we propose a stochastic model that explains that the scale-free topology with exponent in the vicinity of gamma approximately 3/2 found across these three organisms is governed by the log-normal dynamics in the evolution of the enzymes network. Precisely, the fluctuations of the connectivity degree of enzymes in the biochemical pathways between evolutionary distant organisms follow the same conserved dynamical principle, which in the end is the origin of the stationary scale-free distribution observed among species, from Archaea to Eukaryotes. In particular, the log-normal dynamics guarantees the conservation of the scale-free distribution in evolving networks. Furthermore, the log-normal dynamics also gives a possible explanation for the restricted range of observed exponents gamma in the scale-free networks (i.e., gamma > or = 3/2). Finally, our model is also applied to the chemical compounds network of biochemical pathways and the Internet network.

Biological Evolution↗
PubMed2005

Optical magnetoelectric effect in a submicron patterned magnet.

The optical magnetoelectric effect, which is a nonreciprocal directional dichroic response, has been demonstrated in a submicron patterned magnet by monitoring the diffracted visible or near-infrared light intensity. An artificial magnetic superstructure is composed of chevron shaped ">" islands made of the ferromagnetic permalloy Ni(80)Fe(20) with a pitch of 1 microm on silicon substrate, in which both space inversion and time reversal symmetry are broken simultaneously. On the basis of the light-polarization angle and magnetic field H dependence, and also comparing the results with the those of the submicron square patterns, we show that the optical magnetoelectric effect emerges as the finite change (approximately 10(-3) at room temperature in H of 500 Oe) of the diffracted intensity.

Journal Article↗
PubMed2005

Clinical aspects and prognosis of pelvic recurrence of cervical carcinoma.

OBJECTIVE: To identify which patients with locally recurrent cervical carcinoma are potentially curable. METHOD: A total of 664 stage IB-IVA patients were examined following surgery or radiotherapy. RESULT: Among the 664 patients, 193 (29%) developed recurrence. Sixty-seven (35%) of these recurrences were located in the pelvis alone. Among these 67 recurrences, 24 (35%) were central recurrences and the remaining 43 (65%) were pelvic side-wall recurrences. Of the 24 patients with central recurrences, 8 were salvaged. Of these 8 patients, 3 underwent pelvic exenteration, and 5 received optimal radiotherapy. The recurrent tumor in these 5 survivors who received radiotherapy had consisted of a small (<2 cm) tumor. All 43 patients with pelvic wall recurrence developed progressive disease. CONCLUSION: The following patients are potentially curable: patients with a resectable, centrally located tumor who are candidates for pelvic exenteration, and patients with a small central recurrence for whom complete radiation therapy is feasible.

Adenocarcinoma↗