Dynamic Mechanical Properties of Oxide Films Formed on Metallic Surfaces as Measured Using a Tribological Approach at High Temperature

The surface degradation of metals in boiler tubes and turbines in high-temperature corrosive environments causes severe problems in fuel combustion power plant systems. High-temperature resistant materials have been recently developed using a thermal barrier coating (TBC) and high-chromium alloys. Oxide films or coatings formed on metal surfaces at high temperatures can sometimes decrease the corrosion rate. However, the damage to the material is often accelerated by the mechanical removal of corrosion products from the material surface. It is therefore very important to investigate the mechanical and adhesive properties of the oxide films or coatings on metal surfaces used in high-temperature environments. This paper introduces a tribological method that uses a single spherical projectile impact at high temperature to measure the mechanical and adhesive properties of oxide films formed on various metal surfaces. Impact tests were performed on the surfaces of oxide films after their growth in a high-temperature furnace, and the deformed or fractured surfaces were observed in order to measure the mechanical and adhesive properties. The mechanical and adhesive properties of an elastic modulus, fracture, and exfoliation stresses were measured using the impact method, and the results depended on the type of metal oxide films and on the high-temperature environment

Relationship Between Brain Activity and Real-Road Driving Behavior: A Vector-Based Whole-Brain Functional Near-Infrared Spectroscopy Study

Automobile driving requires multiple brain functions. However, the brain regions related to driving behavior are unknown. Therefore, we measured activity of the frontal, parietal and occipital lobes during driving using functional near-infrared spectroscopy (fNIRS). Cortical activation patterns were examined in relation to driving behaviors, such as steering motion, accelerator pedal motion, and speed control. Six healthy adults participated in the experiment. Cerebral oxygen exchange (COE) was calculated based on the oxyhemoglobin and deoxyhemoglobin concentrations measured by fNIRS. The COE and driving behavior data were collected every 1 m and averaged for all subjects. Functional NIRS data for all 98 channels were extracted using principal component analysis. Similarity between extracted components and driving behaviors were confirmed by |cosine similarity|\u3e0.3. Among the factors with confirmed similarity, we identified brain regions with high principal component loading (|PCL|\u3e0.4). Among the 16 COE factors extracted, COE factor 1 and factor 5 exhibited similarity with steering motion (cosine similarity: factor 1, -0.538; factor 5, 0.551). The PCLs of COE factor 1 and factor 5 were high in the frontal lobe (Brodmann areas [BAs] 9, 8, and 4/3) (PCL\u3e0.8). COE factor 6 exhibited a similarity with accelerator pedal motion (cosine similarity: 0.369), and the PCL of COE factor 6 was highest in the parietal lobe (BA7) (PCL= -0.62). Speed control did not exhibit similarity with any COE factor. These findings will contribute to the selection of brain measurement areas when fNIRS is used for vehicle driving assessment

Frontal/Lateral Mandibular Translations-masticatory Movement Relationship

Objective: This study aimed to clarify whether crown restorations with adjusted occlusal surfaces that were formed using frontal/lateral mandibular translations, functioned without interference during mastication. Materials and Methods: In 10 adult volunteers who had healthy normal dentition, frontal and lateral border movement was measured during unilateral mastication and free mastication, using an ultrasound digital mandibular measuring system (ARCUS digma2). Additionally, precise impressions of the upper and lower dental arch were taken, and dental casts were made. These casts were measured using a CAD/CAM scanning system (ARCTICA). For the fabrication of crown restorations, the functionally generated path technique (FGP technique) was used on the monitor for the lower first and second molar. The movement of the opposite teeth on the occlusal surface during frontal and lateral border movement, during unilateral mastication, and during free mastication was considered the functional occlusal surface. The data of the functional occlusal surface generated by frontal/lateral mandibular translations and that of each of the masticatory functional occlusal surfaces were superimposed using three-dimensional data evaluation software (GOM). The difference between these surfaces was evaluated to determine the interference area, maximum interference difference, and average interference difference. Results: Interference was present for all functional occlusal surfaces created by mastication as well as those determined by frontal/lateral mandibular translations. The average interference values, in order of free masticatory movement, habitual masticatory side, and non-habitual masticatory side, were as follows. Interference area: 167.5±20.8 mm2, 121.9±28.5 mm2, 144.6±28.0 mm2; maximum interference distance: 345.0±43.1 μm, 189.0±39.9 μm, 309.0 ± 46.8 μm; average interference distance: 130.0±15.7 μm, 64.0±10.6 μm, 130.0±21.9 μm. Statistically significant differences were found for the maximum interference distance and average interference distance (both p<0.05). Conclusions: The functional occlusal surfaces for each form of mastication demonstrated interference with the functional surface of frontal/lateral mandibular translations. Thus, crown restorations of which the occlusal surfaces were adjusted and formed by frontal/lateral mandibular translations may interfere with mastication

Low expression of γ-glutamyl hydrolase mRNA in primary colorectal cancer with the CpG island methylator phenotype

金沢大学がん研究所分子標的がん医療研究開発センターThe CpG island methylator phenotype (CIMP+) in colorectal cancer (CRC) is defined as concomitant and frequent hypermethylation of CpG islands within gene promoter regions. We previously demonstrated that CIMP+ was associated with elevated concentrations of folate intermediates in tumour tissues. In the present study, we investigated whether CIMP+ was associated with a specific mRNA expression pattern for folate- and nucleotide-metabolising enzymes. An exploratory study was conducted on 114 CRC samples from Australia. mRNA levels for 17 genes involved in folate and nucleotide metabolism were measured by real-time RT-PCR. CIMP+ was determined by real-time methylation-specific PCR and compared to mRNA expression. Candidate genes showing association with CIMP+ were further investigated in a replication cohort of 150 CRC samples from Japan. In the exploratory study, low expression of γ-glutamyl hydrolase (GGH) was strongly associated with CIMP+ and CIMP+-related clinicopathological and molecular features. Trends for inverse association between GGH expression and the concentration of folate intermediates were also observed. Analysis of the replication cohort confirmed that GGH expression was significantly lower in CIMP+ CRC. Promoter hypermethylation of GGH was observed in only 5.6% (1 out of 18) CIMP+ tumours and could not account for the low expression level of this gene. CIMP+ CRC is associated with low expression of GGH, suggesting involvement of the folate pathway in the development and/or progression of this phenotype. Further studies of folate metabolism in CIMP+ CRC may help to elucidate the aetiology of these tumours and to predict their response to anti-folates and 5-fluorouracil/leucovorin. © 2008 Cancer Research UK

Different histological types of non-small cell lung cancer have distinct folate and DNA methylation levels

金沢大学がん研究所分子標的がん医療研究開発センターAberrant DNA methylation is a commonly observed epigenetic change in lung cancer. Folate has been suggested to play a role in the homeostasis of DNA methylation and has also been implicated in cancer chemotherapy. We investigated a possible role for folate in DNA methylation by measuring folate concentrations in tumors and adjacent normal tissues from 72 non-small cell lung cancer (NSCLC) patients. These were compared to DNA methylation levels and to clinicopathological features. Folate concentrations were determined as the sum of 5,10-methylenetetrahydrofolate and tetrahydrofolate. The MethyLight assay was used to quantitate methylation in promoter regions of P16(CDKN2A), APC, CDH13, RARB, RASSF1, RUNX3, and MYOD1. Methylation of LINE-1 repeats was used as a surrogate for global methylation. Folate levels in tumors correlated positively with LINE-1, CDH13, and RUNX3 methylation. Folate concentrations and methylation of LINE-1, RASSF1, and RUNX3 were significantly higher in adenocarcinoma compared to squamous cell carcinoma (SCC). Two sets of array-based data retrieved from the Gene Expression Omnibus consistently showed that expression of FOLR1, a folate transport enzyme, and GGH, an enzyme that prevents folate retention, were higher and lower, respectively, in adenocarcinomas compared to SCC. This was independently validated by quantitative RT-PCR in 26 adenocarcinomas and 13 SCC. Our results suggest that folate metabolism plays a role in aberrant DNA methylation in NSCLC. The histological subtype differences in folate concentration and DNA methylation observed here were associated with distinct expression patterns for folate metabolizing enzymes. These findings may have clinical applications for histology-directed chemotherapy with fluoropyrimidine and anti-folates in NSCLC. © 2009 Japanese Cancer Association

赤芽球癆を合併したT-cell large granular lymphocyte leukemia の一例

T-cell large granular lymphocyte leukemia は長期(6か月以上)にわたる末梢血中の著明な大顆粒リンパ球(large granular lymphocyte;以下,LGL)のモノクローナルな増加によって特徴づけられる疾患で,しばしば赤芽球癆を伴うことが知られている.今回,我々はHCV陽性肝硬変患者に赤芽球癆を合併したT-LGLの1例を経験した.末梢血および骨髄塗抹標本では細胞質内に微細なアズール顆粒を有し,核異型を示すリンパ球の増加がみられ,末梢血および骨髄のフローサイトメトリーおよび骨髄吸引クロット標本の免疫組織化学で,CD3,CD8,CD57陽性リンパ球の増加が確認された.骨髄細胞のPCRではTCRβの再構成を認めず,TCRγおよびTCRδの再構成がみられた.またプレドニゾロン治療にてCD57陽性リンパ球の減少および赤芽球造血の回復が確認されたことから,赤芽球癆を合併したγδT-LGLと診断した.最近,T-LGLにはSTAT3あるいはSTAT5bのSHドメインの遺伝子変異が高頻度にみられることが報告されているが,本症例においては,これらの遺伝子変異は確認できなかった.T-cell large granular lymphocytic leukemia (T-LGL) is characterized by marked increase of monoclonal large granular lymphocytes (LGL) in the peripheral blood over the long term (6 months or more). It has been reported about 20% cases of T-LGL cases are associated with pure red cell aplasia (PRCA). Here, we describe a case of T-LGL associated with PRCA. This case was characterized by increase in the number of CD3+,CD8+,CD57+, and granzyme B-positive lymphocytes with fine azurophilic cytoplasmic granules and nuclear atypia in peripheral blood and bone marrow. The patient was diagnosed havingγδT-LGL because T-cell receptor (TCR)γ and TCRδ gene but not TCRβ gene rearrangement was detected by the PCR of the bone marrow cells. Prednisolone administration decreased in number of the LGL cells, accompanying recover of erythropoiesis. Although somatic mutations in the Src homology 2 domain of STAT3 or STAT5b gene are reported in 70% percent of the T-LGL with PRCA, such STAT mutations could not be detected in this case

Identifying Predictors of Response to Suplatast Tosilate among Patients with Moderate to Severe Bronchial Asthma Receiving Inhaled Steroid Therapy

ABSTRACTBackgroundThe aim of this study was to identify the predictive factors, among laboratory test data and patient background variables, of an efficient response to the anti-allergic agent suplatast tosilate in patients with moderate to severe bronchial asthma.MethodsThe subjects were 44 patients with moderate to severe bronchial asthma on inhaled steroid therapy who were enrolled in a phase II clinical trial of suplatast (300 and 600 mg/day). Improvements in respiratory function parameters and symptom scores during the first 4 weeks of administration of suplatast were assessed to evaluate the response to the drug. Logistic regression analysis was used to relate the response to the independent variables. Secondly, to test whether these results were applicable to clinical practice, we examined the data from a phase III clinical trial of suplatast.ResultsTwenty-two patients were assessed as responders according to our criteria. The percentage of blood eosinophil (%EOS, P = 0.015) and basophil (%BASO, P = 0.019) counts were identified as significant variables to predict responders. When cut-off levels for %EOS and %BASO were set at 7.5 and 1.2, respectively, the sensitivity for prediction of responders with lower %EOS and %BASO was 81.8% (18/22). Furthermore, when we applied the same cut-off levels to subjects of a phase III clinical trial of suplatast, the sensitivity of prediction was found to be as high as 75.0% (6/8).ConclusionsThese results indicate that %EOS and %BASO are good candidates to predict the response to suplatast among patients with moderate to severe bronchial asthma on inhaled steroid therapy. These predictors may contribute, in combination with genomic information, to stratified medical treatment tailored to the individual needs of patients

Combined Stereo-PIV and PLIF Measurements of Transverse Injection in Mach 2 Supersonic Flow

A combined stereoscopic particle image velocimetry (PIV) and acetone planar laser-induced fluorescence (PLIF) measurement system was developed to investigate turbulent mixing of a jet into a supersonic flow. The measurement was performed using a supersonic wind tunnel. Air was injected perpendicular into a Mach 2 freestream with a jet-to-freestream momentum ratio of 2.2. The system successfully measured the molar concentration of the jet using PLIF and the velocity in the flow-field using PIV simultaneously. These data yielded turbulent eddy diffusive flux that is a product of fluctuating velocity (v') and concentration (c'). The eddy flux of the streamwise component (c'u') was negative, and that of the heightwise component (c'v') was positive in the outer jet boundary region. Large-scale structures were periodically generated in the outer jet boundary and convected downstream. This large-scale motion induced negative c'u' and positive c'v' in the outer jet boundary. In the inner region of the jet, the air entrained by the counter-rotating vortices induced a positive v' and negative c' region, resulting in negative c'v'

Functional brain imaging using near-infrared spectroscopy during actual driving on an expressway

The prefrontal cortex is considered to have a significant effect on driving behavior, but little is known about prefrontal cortex function in actual road driving. Driving simulation experiments are not the same, because the subject is in a stationary state, and the results may be different. Functional near-infrared spectroscopy (fNIRS) is advantageous in that it can measure cerebral hemodynamic responses in a person driving an actual vehicle. We mounted fNIRS equipment in a vehicle to evaluate brain functions related to various actual driving operations while the subjects drove on a section of an expressway that was not yet open to the public. Measurements were recorded while parked, and during acceleration, constant velocity driving, deceleration, and U-turns, in the daytime and at night. Changes in cerebral oxygen exchange (ΔCOE) and cerebral blood volume were calculated and imaged for each part of the task. Responses from the prefrontal cortex and the parietal cortex were highly reproducible in the daytime and nighttime experiments. Significant increases in ΔCOE were observed in the frontal eye field (FEF), which has not been mentioned much in previous simulation experiments. In particular, significant activation was detected during acceleration in the right FEF, and during deceleration in the left FEF. Weaker responses during constant velocity driving suggest that FEF function was increased during changes in vehicle speed. As the FEF contributes to control of eye movement in three-dimensional space, FEF activation may be important in actual road driving. fNIRS is a powerful technique for investigating brain activation outdoors, and it proved to be sufficiently robust for use in an actual highway driving experiment in the field of intelligent transport systems