Biomedical subjects

T Iida

Publications and source records attributed to T Iida.

At least 19 recordsLinked to original sources

PubMed2006

Sodium hyaluronate eye drops prevent late-onset bleb leakage after trabeculectomy with mitomycin C.

PURPOSE: To evaluate the efficacy of sodium hyaluronate eye drops for prevention of late-onset bleb leakage after trabeculectomy with mitomycin C (MMC). METHODS: Sixty-eight patients (68 eyes) who had trabeculectomy with MMC from March 1995 to February 2002 at the Marui Eye Clinic or the Department of Ophthalmology, Fukushima Medical University Hospital were examined in this study. Twenty-two were treated postoperatively with sodium hyaluronate eye drops (sodium hyaluronate group) and 46 eyes were not treated postoperatively (control group). The blebs were classified according to the avascular area, epithelial defect and degree of bleb wall leakage. Both groups were assigned classes (0, avascular or partial avascular bleb; 1, avascular or partial avascular bleb with an epithelial defect; 2, avascular or partial avascular bleb with oozing; 3, avascular or partial avascular bleb with a point of leakage). RESULTS: Follow-up duration ranged from 10 to 116 months (mean+/-SD, 57.6+/-30.5). The incidence of reclassification from class 1 to class 0 was significantly greater in the sodium hyaluronate group (four of six class 1 eyes improved to class 0 after application of sodium hyaluronate eye drops) than in the control group (zero of 10 eyes) (P=0.008). And, the incidence of reclassification from class 1 to class 2 or class 3 was significantly smaller in the sodium hyaluronate group (one of six eyes) than in the control group (nine of 10 eyes) (P=0.008). CONCLUSIONS: Sodium hyaluronate eye drops may prevent late-onset bleb leakage after trabeculectomy with MMC.

Adult↗

PubMed2006

Measurement of atmospheric neutrino flux consistent with tau neutrino appearance.

A search for the appearance of tau neutrinos from nu(mu) <--> nu(tau) oscillations in the atmospheric neutrinos has been performed using 1489.2 days of atmospheric neutrino data from the Super-Kamiokande-I experiment. A best fit tau neutrino appearance signal of 138+/-48(stat)-32(+15)(syst) events is obtained with an expectation of 78+/-26(syst). The hypothesis of no tau neutrino appearance is disfavored by 2.4 sigma.

Journal Article↗

PubMed2006

A microbeam X-ray diffraction study of insulin spherulites.

The peptide hormone insulin forms a spherical aggregate, called a spherulite, at low pH and high temperature. A spherulite is composed of a core and many fibrils extending from it. These fibrils are thought to be amyloid fibers with a beta-sheet structure. In the present study, spherulites with a diameter of 50-100 microm were examined by X-ray fiber diffraction using a 6 microm beam. When a spherulite was scanned with the microbeam and the observed diffraction patterns were arranged in a two-dimensional array, the direction of the scatter was centrosymmetric, demonstrating a symmetric growth of fibrils. There were diffraction peaks at Bragg spacings of 23 nm, 3.3 nm and 1.2 nm in the direction perpendicular to the fibrils and 0.48 nm along the fibrils. The 0.48 nm reflection shows that the hydrogen bonds between beta-strands are along the fibril. The 23 nm reflection corresponds to the separation between fibrils, the 3.3 nm reflection is due to the arrangement of protofilaments, and the 1.2 nm reflection arises from the arrangement of peptide chains. On the basis of these results, a model of a fibril with an extended insulin molecule is proposed.

Amino Acid Sequence↗

PubMed2006

Prevention of Salmonella cross-contamination in an oilmeal manufacturing plant.

AIMS: The mechanisms of Salmonella contamination in an oilmeal plant were investigated and the basic data were collected in order to achieve control of Salmonella in oilmeal. METHODS AND RESULTS: Salmonella was detected in all contamination vectors and environmental factors investigated, namely: operators, processing floor, dust in the air and rodents. In particular, high concentrations of Salmonella were detected on the processing floor of the manufacturing area, which has high oil content. Steam was the most effective disinfection method used for the processing floor, as the effects of heat sterilization and disinfection may work in tandem. In addition, restricting the movement of operators of the production chain remarkably reduced Salmonella contamination, even in areas of otherwise high contamination. CONCLUSIONS: Within the oilmeal plant, high Salmonella contamination rates for the processing floor represent the greatest risk of contamination of oilmeal via operators, dust in the air and rodents. Therefore, control of the processing floor is the most important means for reducing the oilmeal contamination rate. SIGNIFICANCE AND IMPACT OF THE STUDY: Specific Salmonella control methods for oilmeal plants have been established.

Animal Feed↗

PubMed2006

The vibratory characteristics of obturators with different bulb height and form designs.

The aim of the present study was to investigate whether the vibratory characteristics of obturator prostheses are affected by bulb design, i.e.: the hollow or buccal flange type, and different lateral and medial bulb heights. Buccal flange and hollow bulb obturator prostheses were fabricated with two different lateral bulb wall heights and two different medial bulb wall heights. Ultimately, eight obturator prostheses were prepared for evaluation of their vibratory characteristics. The frequency-response functions were recorded on an FFT analyzer to identify their vibratory characteristics. A transient response simulation was carried out in which an impact was applied to the non-defect side. The decay rate, damping time and maximum amplitude of the retainers were statistically analysed by anova with Scheffé's test (P < 0.05). The decay rate of every buccal flange type was higher and damping time was shorter than those of every hollow type, except between a pair with low lateral and low medial bulb walls. The maximum amplitude values of four obturators with low medial bulb walls were significantly lower than those of four obturators with high medial walls. The buccal flange obturator prosthesis with high lateral and low medial walls showed the maximum decay rate and the minimum amplitude of the retainers on molars. Vibration analysis suggests that a buccal flange obturator prosthesis with high lateral and low medial walls is preferable.

Analysis of Variance↗

PubMed2006

Predictors of long-term survival with pulmonary metastasectomy for osteosarcomas and soft tissue sarcomas.

AIM: The control of pulmonary metastases is important for long-term survival of the patients with osteosarcomas and soft tissue sarcomas. METHODS: To evaluate the efficacy of aggressive pulmonary metastasectomy for those patients, we reviewed 105 cases (44 osteosarcomas, and 61 soft tissue sarcomas) treated in our hospital. RESULTS: The number of metastases was only the significant risk factor for the curability of the metastasectomy (logistic regression analysis, P=0.0274). The 5-year and 10-year survival rate were 43.6% and 32%. The curability was only independent prognostic factor on multivariate analysis (P=0.0008). CONCLUSIONS: Early detection of pulmonary metastasis, multimodal perioperative treatment, and design for minimizing the volume of resected lung tissues will enable complete and repeat resections for the achievement of long-term survival.

Adolescent↗

PubMed2005

Significance of lymph node micrometastasis in pN0 hilar bile duct carcinoma.

AIMS: To examine micrometastasis in node-negative hilar bile duct carcinoma (HBDC) using an immunohistochemical method and evaluated the clinical significance. METHODS: Four hundred and twenty three regional lymph nodes from 28 patients with node-negative HBDC who had undergone a resection were immunostained with an antibody against cytokeratins eight and 18 (CAM 5.2). RESULTS: Lymph node micrometastasis was detected in 11 of the 28 patients and 14 of the 423 lymph nodes. Lymph node micrometastasis was significantly correlated with the pT classification (p=0.03), the histopathological grading (p=0.01) and venous invasion (p=0.05). The 5-year survival rate of the patients with lymph node micrometastasis was 21.8%, as opposed to 66.5% in the patients without micrometastasis. Patients with micrometastasis showed a significantly poorer survival rate than those without micrometastasis (p=0.02). CONCLUSION: The results suggest that immunohistochemically detected lymph node micrometastasis has an impact on the outcome in HBDC.

Adult↗

PubMed2005

The transport mechanisms of (222)Rn in soil at Tateishi as an anomaly spot in Japan.

The (222)Rn concentration profiles in soil have been measured at an anomaly spot in Tateishi, Japan. In winter, the concentrations were low and showed a negative gradient with depth, but in other seasons, the concentration had both positive and negative gradients with depth, and dramatically changed by time. On the assumption that there was ventilation in deep layers and with driving forces of wind and temperatures, these phenomena were successfully explained. This finding would contribute to a numerical model for (222)Rn transport in soil.

Computer Simulation↗

PubMed2005

A microscale in vitro physiological model of the liver: predictive screens for drug metabolism and enzyme induction.

In vitro models of the liver using isolated primary hepatocytes have been used as screens for measuring the metabolism, toxicity and efficacy of xenobiotics, for studying hepatocyte proliferation, and as bioartificial liver support systems. Yet, primary isolated hepatocytes rapidly lose liver specific functions when maintained under standard in vitro cell culture conditions. Many modifications to conventional culture methods have been developed to foster retention of hepatocyte function. Still, not all of the important functions -- especially the biotransformation functions of the liver -- can as yet be replicated at desired levels, prompting continued development of new culture systems. In the first part of this article, we review primary hepatocyte in vitro systems used in metabolism and enzyme induction studies. We then describe a scalable microreactor system that fosters development of 3D-perfused micro-tissue units and show that primary rat cells cultured in this system are substantially closer to native liver compared to cells cultured by other in vitro methods, as assessed by a broad spectrum of gene expression, protein expression and biochemical activity metrics. These results provide a foundation for extension of this culture model to other applications in drug discovery -- as a model to study drug-drug interactions, as a model for the assessment of acute and chronic liver toxicity arising from exposure to drugs or environmental agents; and as a disease model for the study of viral hepatitis infection and cancer metastasis.

Animals↗

PubMed2004

Ion generation in a low-density plastic foam by interaction with intense femtosecond laser pulses.

Energetic proton generation in low-density plastic (C5H10) foam by intense femtosecond laser pulse irradiation has been studied experimentally and numerically. Plastic foam was successfully produced by a sol-gel method, achieving an average density of 10 mg/cm(3). The foam target was irradiated by 100 fs pulses of a laser intensity 1 x 10(18) W/cm(2). A plateau structure extending up to 200 keV was observed in the energy distribution of protons generated from the foam target, with the plateau shape well explained by Coulomb explosion of lamella in the foam. The laser-foam interaction and ion generation were studied qualitatively by two-dimensional particle-in-cell simulations, which indicated that energetic protons are mainly generated by the Coulomb explosion. From the results, the efficiency of energetic ion generation in a low-density foam target by Coulomb explosion is expected to be higher than in a gas-cluster target.

Journal Article↗

PubMed2004

A case study of radon-222 transport from continental North-East Asia to the Japanese islands in winter by numerical analysis.

A case study of the regional transport ( approximately 3000 km) of radon-222 ((222)Rn) from continental North-East Asia to the Japanese islands was performed by numerical analysis using five separate source areas (South, Middle and North China, Russia and Korea), while a seasonal northwest wind blew over the Japan Sea. The results for three periods (Term I: 16-18, Term II: 22-25 and Term III: 27-28 in December 1990) were compared with concentrations measured at the Kanazawa site (near the coast of the Japan Sea facing the seasonal wind) and the Nagoya site (overland and downwind on the shores of the Pacific Ocean). Most of the (222)Rn at the Kanazawa site was calculated to come from North China and Korea in Term I, Middle China, North China, and Korea in Term II, and Russia and Korea in Term III. The considerable differences in the origins of (222)Rn emanated from the continent were estimated between Terms I, II and III, even though the similar northwest wind was dominant over the Japan Sea. A contour line analysis indicated movement of (222)Rn emanated from Middle China in a northerly direction first and then a southeasterly direction, resulting from low pressure. The results suggest that the low-pressure systems play an important role in the transport of (222)Rn in North-East Asia.

Air Movements↗

PubMed2004

Quantitative detection of periodontal pathogens using real-time polymerase chain reaction with TaqMan probes.

Quantitative analysis, with identification of periodontopathic bacteria, is important for the diagnosis, therapeutic evaluation and risk assessment of periodontal disease. We developed a highly sensitive and specific method using real-time polymerase chain reaction (PCR) to detect and quantify six periodontal bacteria: Porphyromonas gingivalis, Tannerella forsythia, Actinobacillus actinomycetemcomitans, Treponema denticola, Prevotella intermedia, and Prevotella nigrescens. Species-specific TaqMan probe/primer sets were designed according to 16S ribosomal RNA gene sequences. Plaque and tongue debris specimens were collected from 10 patients with advanced periodontitis and 10 periodontal healthy individuals and analyzed. All species, except for P. nigrescens, were detected in samples from diseased sites in significantly greater numbers than in those from healthy sites, whereas greater numbers of P. nigrescens were found in the controls. These results suggest that the present real-time PCR method with the designed probe/primer sets enabled sensitive detection of the six periodontal bacteria, and may also assist future microbial studies of periodontal diseases.

Aggregatibacter actinomycetemcomitans↗

PubMed2004

Establishment and characterization of two cell lines (HEC-155, HEC-180) derived from uterine papillary serous adenocarcinoma.

Uterine papillary serous adenocarcinoma (UPSC) is an uncommon histologic subtype of endometrial cancer that characteristically behaves aggressively with a poor prognosis. We established two novel cell lines derived from UPSC designated HEC-155 and HEC-180. Both cell lines have been growing steadily in monolayer cultures for over ten years. Overexpression of p53, Ki67 and p27 was detected in both cell lines by immunohistochemistry. Using a DNA sequencing technique, a point mutation of p53 was detected in exon 8, codon 286 in HEC-155 and in exon 6, codon 195 in HEC-180. These newly established cell lines should be useful for investigating the characteristics of UPSC.

Biopsy, Needle↗

PubMed2003

Augmentation of antigen-specific cytokine responses in the early phase of vaccination with a live-attenuated simian/human immunodeficiency chimeric virus expressing IFN-gamma.

A nef-deleted SHIV-NM-3rN (SHIV-NI) was previously shown to be nonpathogenic and to induce protective immunity. In the present study, a SHIV-NI expressing human interferon-gamma (SHIV-IFN-gamma) was constructed and the effect of co-expression of IFN-gamma on virus replication and immunopotentiation was investigated in macaques that were vaccinated with both viruses, by comparing cytokine responses during the first 4 weeks after vaccination. Peripheral blood mononuclear cells (PBMC) isolated from vaccinated macaques were stimulated with inactivated viral particles for 24 h, and the production of IL-2, IL-4, IL-6, IL-10, IL-12, TNF-alpha and IFN-gamma was determined by ELISA and flow cytometry. All of the vaccinated macaques showed increases in cytokine production. However, the production of IFN-gamma (Th1-type cytokine) was more rapidly induced by SHIV-IFN-gamma vaccination, and IFN-gamma-producing cells appeared to be still increasing at 4 weeks after vaccination, although the difference of virus replication during the time was not significant in contrast to in vitro replication in cultured PBMC. These results suggest that co-expression of IFN-gamma with SHIV can modulate the antiviral immune responses into the Th1 type response, which would probably provide more protective immunity.

Animals↗

PubMed2003

Expression of foreign proteins in Escherichia coli by fusing with an archaeal FK506 binding protein.

Improper protein-folding often results in inclusion-body formation in a protein expression system using Escherichia coli. To express such proteins in the soluble fraction of E. coli cytoplasm, we developed an expression system by fusing the target protein with an archaeal FK506 binding protein (FKBP). It has been reported that an archaeal FKBP from a hyperthermophilic archaeon, Thermococcus sp. KS-1 (TcFKBP18), possesses not only peptidyl-prolyl cis-trans isomerase activity, but also chaperone-like activity to enhance the refolding yield of an unfolded protein by suppressing irreversible protein aggregation. To study the effect of this fusion strategy with FKBP on the expression of foreign protein in E. coli, a putative rhodanese (thiosulfate sulfurtransferase) from a hyperthermophilic archaeon and two mouse antibody fragments were used as model target proteins. When they were expressed alone in E. coli, they formed insoluble aggregates. Their genes were designed to be expressed as a fusion protein by connecting them to the C-terminal end of TcFKBP18 with an oligopeptide containing a thrombin cleavage site. By fusing TcFKBP18, the expression of the target protein in the soluble fraction was significantly increased. The percentage of the soluble form in the expressed protein reached 10-28% of the host soluble proteins. After purification and protease digestion of the expressed antibody fragment-TcFKBP18 fusion protein, the cleaved antibody fragment (single-chain Fv) showed specific binding to the antigen in ELISA. This indicated that the expressed antibody fragment properly folded to the active form.

Archaeal Proteins↗

PubMed2003

Detection of Japanese yam mosaic virus by RT-LAMP.

Arapid and simple procedure is described to detect the genomic RNA molecule of Japanese yam mosaic potyvirus (JYMV). This method, named RT-LAMP, allows direct detection of RNA from infected plants without careful RNA extraction, rapid thermal cycling and gel electrophoresis. RT-LAMP was successfully applied to leaves, propagules and roots of Japanese yam infected with JYMV. One of the characteristics of the RT-LAMP method is its ability to synthesize an extremely large amount of DNA. Accordingly, a large amount of by-product, pyrophospate ion, is produced yielding a white precipitate of magnesium pyrophosphate in the reaction mixture. The presence or absence of this white precipitate allows easy detection of the amplification of JYMV genomic RNA without gel electrophoresis.

Base Sequence↗

PubMed2003

TRPV1 activation and induction of nociceptive response by a non-pungent capsaicin-like compound, capsiate.

Capsiate is a capsaicin-like ingredient of a non-pungent cultivar of red pepper, CH-19 sweet. To elucidate the mechanisms underlying the non-pungency of capsiate, we investigated whether capsiate activates the cloned capsaicin receptor, TRPV1 (VR1). In patch-clamp experiments, capsiate was found to activate TRPV1 expressed transiently in HEK293 cells with a similar potency as capsaicin. Capsiate induced nociceptive responses in mice when injected subcutaneously into their hindpaws with a similar dose dependency as capsaicin. These data indicate that the non-pungent capsiate is an agonist for TRPV1 and could excite peripheral nociceptors. In contrast to this, capsiate did not induce any significant responses when applied to the skin surface, eye or oral cavity of mice, suggesting that capsiate requires direct access to nerve endings to exhibit its effects. Capsiate was proved to have high lipophilicity and to be easily broken down in normal aqueous conditions, leading to less accessibility to nociceptors. Another highly lipophilic capsaicin analogue, olvanil, was similar to capsiate in that it did not produce irritant responses when applied to the skin surface, although it could activate TRPV1. Taken together, high lipophilicity and instability might be critical determinants for pungency and so help in understanding the effects of capsaicin-related compounds.

Animals↗

PubMed2002

Classification and examination of halitosis.

In this paper, the classification of halitosis and the examination procedures used in diagnosing halitosis are outlined. Halitosis is classified into categories of genuine halitosis, pseudo-halitosis and halitophobia. Genuine halitosis is subclassified into physiologic halitosis and pathologic halitosis. Pathologic halitosis itself is subdivided into oral and extraoral halitosis. Patients diagnosed with pseudo-halitosis and halitophobia usually complain about having oral malodour that does not really exist. Pseudohalitosis can be treated by dental practitioners, but halitophobic patients must be referred to psychological specialists. Oral malodour can be measured using an organoleptic measurement or a gas chromatography analysis. The organoleptic measurement is the most practical procedure with which one can evaluate oral malodour. Gas chromatography (GC) analysis using a flame photometric detector has been shown to be the gold standard for measuring oral malodour, owing its reputation to its objectivity and reproducibility. Moreover, GC is specific for volatile sulphur compounds (VSC), which are the main causes of oral malodour. It has been demonstrated that there is a high correlation between the intensity of oral malodour and the VSC concentration as measured by GC.

Chromatography, Gas↗