34 research outputs found

    An investigation on moisture and water absorption in cement paste with electrical resistance method

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    Moisture in concrete is one of main factors related to degradation and deterioration of concrete structure, and there are various moisture transport phenomena in concrete such as drying and absorbing. There are a lot of previous studies on the drying process of concrete to clarify the mechanisms of creep as well as shrinkage. However, few studies have been reported on the process of water absorption and moisture absorption although carbonation and chloride attack are strongly related to moisture and water absorbing. It is necessary to investigate moisture transfer in concrete in detail. This study investigated the moisture transfer in moisture and water absorbing processes in cement paste by using electrical resistance method to understand how moisture and water transfer into concrete. Cement paste specimens with water-to-cement ratios (W/Cs) of 0.35 and 0.55 were prepared in this study. Stainless steel rods of 0.9 mm in diameter were arranged at an interval of 4 mm in the specimen for measuring the electrical resistance. The specimens for moisture and water absorbing test were cured in water at 20 ºC for 28 days and stored at 20 ºC and a relative humidity of 0% and 70% as reference and the national average of the annual average relative humidity in Japan, respectively. The electrical resistances were measured through the stainless-steel rods and converted to electrical resistivity. The calibration test was also conducted to obtain the relationship between the electrical resistivity and the internal relative humidity (IRH), which was used to know IRH in cement paste specimen. As a result, the rate of moisture transfer in the specimen at initial internal relative humidity (IIRH) of 0% was higher than that at IIRH of 70%. Additionally, the rate of moisture transfer in the specimen at any IIRH depends on the total pore volume in the specimen

    Gender-Dependent Characteristics of Serum 1,25-Dihydroxyvitamin D/25-Hydroxyvitamin D Ratio for the Assessment of Bone Metabolism

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    Y Objectives Vitamin D deficiency, which is common worldwide, increases the risks of falls and fractures and can lead to increased morbidity and mortality. However, the clinical utility and relevance of vitamin D activation remain unknown. The aim of the present study was to clarify the clinical usefulness of serum 1,25-dihydroxyvitamin D (1,25D)/25-hydroxyvitamin D (25D) ratio for assessment of the extent of bone metabolism. Methods We retrospectively screened data for 87 patients whose serum 1,25D and 25D levels were measured. Eight patients who were taking vitamin D preparations were excluded, and data for 79 patients (33 males and 46 females) were analyzed. Since menopausal status can be associated with serum vitamin D level, we divided the patients by gender and divided the female patients into two groups at the age of 50 years. Results The median serum 1,25D/25D ratio was significantly lower in males than in females, with the most considerable difference in all males [4.1 (interquartile range: 2.3-5.8) x 10(-3)] versus elderly females (aged >= 50 years) [7.9 (3.3-10.1) x 10(-3)). Main disorders were endocrine (30.6%), inflammatory (18.5%), and bone related (16.7%) disorders. The ratios of serum 1,25D/25D had significant negative correlations with femoral dual-energy X-ray absorptiometry % young adult mean (DEXA %YAM) (R=-0.35) and lumbar DEXA %YAM (R=-0.32). Significant correlations were found between the 1,25D/25D ratio and serum levels of inorganic phosphate (iP), parathyroid hormone, and alkaline phosphatase (ALP). The 1,25D/25D ratio had gender specific characteristics: the ratio was significantly correlated with age in males (R=-0.49), while it was significantly correlated with BMI in females (R=0.34). Conclusions The results of this study suggested that vitamin D activity is negatively correlated with bone mineral density, being reduced in aged males but enhanced in obese females

    Hemorrhagic infarction at 33 days after birth in a healthy full-term neonate

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    Intraparenchymal hemorrhage in the full-term neonate rarely occurs more than 2 weeks after birth, and its definitive cause remains unclear. In the present report, a case of a patient with intraparenchymal hemorrhage occurring 33 days after birth is described. Histological examination of the brain tissue obtained during hematoma evacuation through craniotomy showed hemorrhagic infarction. Patent foramen ovale may have been present and this may have led to spontaneous paradoxical cerebral embolism followed by hemorrhagic infarction

    自閉症スペクトラム障害(ASD) 児・者に対する相互交渉スキル支援プログラムの実践と効果(その2):言語面への効果を中心に

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    報告Reports 本研究は、自閉症スペクトラム障害(ASD)児・者を対象に実施した「相互交渉スキル」(対人葛藤場面において自他の要求を調整しながら交渉するスキル)の支援プログラムの効果について検討した第2報である。対象者はASD の診断を受けた小学4年生~中学2年生の7名であった。今回のプログラムは「相互交渉をする上で必要な考え方や解決案」「話し合いの仕方の手順」に関するワークと、それらを用いてのロールプレイ等、第1 報のものと基本的構成は同様であるが、視覚的な工夫として“気持ちのてんびん”と“気持ちのものさし”を新たに加えるなど改良した。プログラムの前後に個別面接による対人交渉方略の測定を行い、主に方略における言語面の変化に関してプログラムの効果を検討した。その結果、プログラムの実施により「解決方略の言語面」や「解決の目標」において、自他両方の視点を大事にするような変化が見られ、主にプログラム中の視覚的工夫による効果が考察された

    FXYD3 functionally demarcates an ancestral breast cancer stem cell subpopulation with features of drug-tolerant persisters

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    乳がんの再発を起こす原因細胞を解明. 京都大学プレスリリース. 2023-11-16.The heterogeneity of cancer stem cells (CSCs) within tumors presents a challenge in therapeutic targeting. To decipher the cellular plasticity that fuels phenotypic heterogeneity, we undertook single-cell transcriptomics analysis in triple-negative breast cancer (TNBC) to identify subpopulations in CSCs. We found a subpopulation of CSCs with ancestral features that is marked by FXYD domain–containing ion transport regulator 3 (FXYD3), a component of the Na⁺/K⁺ pump. Accordingly, FXYD3⁺ CSCs evolve and proliferate, while displaying traits of alveolar progenitors that are normally induced during pregnancy. Clinically, FXYD3⁺ CSCs were persistent during neoadjuvant chemotherapy, hence linking them to drug-tolerant persisters (DTPs) and identifying them as crucial therapeutic targets. Importantly, FXYD3⁺ CSCs were sensitive to senolytic Na⁺/K⁺ pump inhibitors, such as cardiac glycosides. Together, our data indicate that FXYD3⁺ CSCs with ancestral features are drivers of plasticity and chemoresistance in TNBC. Targeting the Na⁺/K⁺ pump could be an effective strategy to eliminate CSCs with ancestral and DTP features that could improve TNBC prognosis

    A Microfluidic Cell Stretch Device to Investigate the Effects of Stretching Stress on Artery Smooth Muscle Cell Proliferation in Pulmonary Arterial Hypertension

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    A microfluidic cell stretch device was developed to investigate the effects of stretching stress on pulmonary artery smooth muscle cell (PASMC) proliferation in pulmonary arterial hypertension (PAH). The microfluidic device harbors upper cell culture and lower control channels, separated by a stretchable poly(dimethylsiloxane) membrane that acts as a cell culture substrate. The lower channel inlet was connected to a vacuum pump via a digital switch-controlled solenoid valve. For cyclic stretch at heartbeat frequency (80 bpm), the open or close time for each valve was set to 0.38 s. Proliferation of normal PASMCs and those obtained from patients was enhanced by the circumferential stretching stimulation. This is the first report showing patient cells increased in number by stretching stress. These results are consistent with the abnormal proliferation observed in PAH. Circumferential stretch stress was applied to the cells without increasing the pressure inside the microchannel. Our data may suggest that the stretch stress itself promotes cell proliferation in PAH

    Non‐esterified fatty acid‐associated ability of follicular fluid to support porcine oocyte maturation and development

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    Abstract Purpose The effect of supplementing maturation medium with follicular fluid (FF) was examined according to its non‐esterified fatty acid (NEFA) content or with a fatty acid mixture (FA‐Mix) on the developmental competence of oocytes, as well as the mitochondrial quality and quantity in the oocytes and cumulus cells. Method Porcine oocytes from a slaughterhouse were used. Results The FF or FA‐Mix in maturation medium increased the lipid content in both the oocytes and the cumulus cells, but the adenosine triphosphate content was differentially affected. The FF supplementation increased the mitochondrial DNA copy number, survival of cumulus cells, and rate of oocyte development to the blastocyst stage, whereas the FA‐Mix supplementation did not show these effects. The expression levels of GPC4, PFKP, PRDX3, and TFAM in the cumulus cells increased after FF supplementation, but the expression of GJA1 decreased, compared with the cells that were cultured without FF. Conclusion Adding FF and FA‐Mix to the maturation medium increased the lipid content in the oocytes and cumulus cells. The effects of FF on the cumulus cells and oocytes were not observed after FA‐Mix supplementation, indicating that the concentration of the NEFAs in the FF are closely associated with an ability to support oocyte maturation and the metabolism of cumulus cells and oocytes
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