179 research outputs found
Microenvironment Modulates Osteogenic Cell Lineage Commitment in Differentiated Embryonic Stem Cells
Background: Due to their self-renewal, embryonic stem cells (ESCs) are attractive cells for applications in regenerative medicine and tissue engineering. Although ESC differentiation has been used as a platform for generating bone in vitro and in vivo, the results have been unsatisfactory at best. It is possible that the traditional culture methods, which have been used, are not optimal and that other approaches must be explored. Methodology/Principal Findings: ESCs were differentiated into osteoblast lineage using a micro-mass approach. In response to osteogenic differentiation medium, many cells underwent apoptosis, while others left the micro-mass, forming small aggregates in suspension. These aggregates were cultured in three different culture conditions (adhesion, static suspension, and stirred suspension), then examined for osteogenic potential in vitro and in vivo. In adhesion culture, ESCs primed to become osteoblasts recommitted to the adipocyte lineage in vitro. In a static suspension culture, resulting porous aggregates expressed osteoblasts markers and formed bone in vivo via intermembranous ossification. In a stirred suspension culture, resulting non-porous aggregates suppressed osteoblast differentiation in favor of expanding progenitor cells. Conclusions/Significance: We demonstrate that microenvironment modulates cell fate and subsequent tissue formation during ESC differentiation. For effective tissue engineering using ESCs, it is important to develop optimized cell culture/ differentiation conditions based upon the influence of microenvironment
Advanced Learning Environment Based on Intelligent Explanation Capability for Object Understanding Support
電気回路などの対象の理解に対する教育的支援では,対象に関する説明が有力な支援手段として用いられている.説明による教育的支援では,一つの対象に関して一般にさまざまに存在する説明を,対象に関する何を理解させるのか,すなわち支援目的に応じて使い分けることが重要である.また,単に説明を与えるだけでなく,学生の理解を誘導したり学生の質問に応答する過程で有効に説明を利用することが支援の高度化に不可欠である.本論文では,電気回路を対象領域として,このような支援の高度化を指向したITS,LEIEC/Iについて述べる.筆者らは,電気回路に対する理解誘導・質問応答において回路に関するさまざまな説明を使い分けるために,①視点および対象モデルの概念を用いた対象理解の定式化による支援目的の分類,②支援目的に基づく説明の整理,③整理した説明を計算機上で可能とする説明機能EXSELの開発,を行った.本論文では,理解誘導・質問応答におけるEXSELの運用による説明の使い分けを中心に論じる.特に,学生の理解誘導において,回路に関するさまざまな説明を使い分けることによって,LEIEC/Iが説明による高度な教育的支援を可能にしていることを示す
New herpetofaunal records from Gunung Mulu National Park and its surrounding areas in Borneo
Gunung Mulu National Park (GMNP) in northwestern Borneo is marked by high species diversity and diverse environments. We present one new amphibian and ten new reptile records from GMNP and its surrounding area. In the records, Asthenodipsas jamilinaisi and Garthius chaseni were newly recorded in the Sarawak State. We also present the first record of Cyrtodactylus muluensis from outside of GMNP and the second record of Opisthotropis typica from the park. Combined with previous information, a total of 108 amphibians and 104 reptiles are known from GMNP, and their preferred habitat types are diverse. Furthermore, observed male-male combat of Dopasia buettikoferi is the first detailed description of the genus. Two color morphs of D. buettikoferi had an identical ND2 haplotype and appeared to be the same species. The present study provides new information about Bornean amphibians and reptiles, and also emphasizes the importance of continuous monitoring
BALB/c-Fcgr2b−/−Pdcd1−/− mouse expressing anti-urothelial antibody is a novel model of autoimmune cystitis
We report the impact of anti-urothelial autoantibody (AUAb) on urinary bladder phenotype in BALB/c mice deficient of the FcγRIIb and PD-1. AUAb was present in serum samples from approximately half of the double-knockout (DKO) mice, as detected by immunofluorescence and immunoblots for urothelial proteins including uroplakin IIIa. The AUAb-positive DKO mice showed degeneration of urothelial plaque and umbrella cells, along with infiltration of inflammatory cells in the suburothelial layer. TNFα and IL-1β were upregulated in the bladder and the urine of AUAb-positive DKO mice. Voiding behavior of mice was analyzed by the Voided Stain on Paper method. 10-week-old and older AUAb-positive DKO mice voided significantly less urine per void than did wild type (WT) mice. Furthermore, administration of the AUAb-containing serum to WT mice significantly reduced their urine volume per void. In summary, this report presents a novel comprehensive mouse model of autoimmune cystitis
<Abstract of Published Report>Effect of Cigarette Smoke on the Mutagenic Activation of Environmental Carcinogens by Rodent Liver.
E ect of Body Mass Index on Survival a er Curative erapy for non-B non-C Hepatocellular Carcinoma
Variation in Dehydration Tolerance, ABA Sensitivity and Related Gene Expression Patterns in D-Genome Progenitor and Synthetic Hexaploid Wheat Lines
The wild wheat Aegilops tauschii Coss. has extensive natural variation available for breeding of common wheat. Drought stress tolerance is closely related to abscisic acid (ABA) sensitivity. In this study, 17 synthetic hexaploid wheat lines, produced by crossing the tetraploid wheat cultivar Langdon with 17 accessions of Ae. tauschii, were used for comparative analysis of natural variation in drought tolerance and ABA sensitivity. Ae. tauschii showed wide natural variation, with weak association between the traits. Drought-sensitive accessions of Ae. tauschii exhibited significantly less ABA sensitivity. D-genome variations observed at the diploid genome level were not necessarily reflected in synthetic wheats. However, synthetic wheats derived from the parental Ae. tauschii accessions with high drought tolerance were significantly more tolerant to drought stress than those from drought-sensitive accessions. Moreover, synthetic wheats with high drought tolerance showed significantly higher ABA sensitivity than drought-sensitive synthetic lines. In the hexaploid genetic background, therefore, weak association of ABA sensitivity with drought tolerance was observed. To study differences in gene expression patterns between stress-tolerant and -sensitive lines, levels of two Cor/Lea and three transcription factor gene transcripts were compared. The more tolerant accession of Ae. tauschii tended to accumulate more abundant transcripts of the examined genes than the sensitive accession under stress conditions. The expression patterns in the synthetic wheats seemed to be additive for parental lines exposed to drought and ABA treatments. However, the transcript levels of transcription factor genes in the synthetic wheats did not necessarily correspond to the postulated levels based on expression in parental lines. Allopolyploidization altered the expression levels of the stress-responsive genes in synthetic wheats
Association between changes in loop diuretic dose and outcomes in acute heart failure
AIMS: Little is known about the association between the starting of or dose changes in loop diuretics during acute heart failure (AHF) hospitalization and post-discharge outcomes. We investigated the clinical impact of starting loop diuretics and changing the loop diuretics dose during hospitalization on post-discharge outcomes. METHODS AND RESULTS: From the Kyoto Congestive Heart Failure registry, 3665 consecutive patients hospitalized for HF and discharged alive were included in this study. We analysed 1906 patients without loop diuretics on admission and were discharged alive and 1759 patients who received loop diuretics on admission and were discharged alive. The primary outcome measure was all-cause death. Of the 1906 patients without loop diuretics on admission, 1366 (71.7%) patients started loop diuretics during the index AHF hospitalization. Starting loop diuretics was not associated with lower post-discharge mortality [adjusted hazard ratio (HR) 0.92, 95% confidence interval (CI) 0.68-1.25]. Of the 1759 patients who received loop diuretics on admission, loop diuretic dose was decreased in 23.8%, unchanged in 44.6%, and increased in 31.6% of the patients. Changes in the dose at discharge compared with no change in dose were not associated with lower risk of post-discharge mortality (decrease relative to no change: adjusted HR 0.98, 95% CI 0.76-1.28; increase relative to no change: adjusted HR 1.00, 95% CI 0.78-1.27). Compared with no loop diuretics at discharge, a loop diuretics dose of ≥80 mg at discharge was associated with higher post-discharge mortality risk. CONCLUSIONS: In patients with AHF, we found no association between the starting of loop diuretics and post-discharge outcomes and between dose changes and post-discharge outcomes
Association between Body Mass Index and Prognosis of Patients Hospitalized With Heart Failure
The prognostic implications of very low body mass index (BMI) values remain unclear in patients with acute decompensated heart failure (ADHF). This study aimed to investigate the prognostic impact of BMI classification based on the World Health Organization criteria in patients with ADHF. Among 3509 patients with ADHF and available BMI data at discharge in 19 participating hospitals in Japan between October 2014 and March 2016, the study population was divided into five groups; (1) Severely underweight: BMI < 16 kg/m², (2) Underweight: BMI ≥ 16 kg/m² and < 18.5 kg/m², (3) Normal weight: BMI ≥ 18.5 kg/m² and < 25 kg/m², (4) Overweight: BMI ≥ 25 kg/m² and < 30 kg/m² (5) Obese: BMI ≥ 30 kg/m². The primary outcome measure was all-cause death. The median follow-up duration was 471 days, with 96.4% follow up at 1-year. The cumulative 1-year incidence of all-cause death was higher in underweight groups, and lower in overweight groups (Severely underweight: 36.3%, Underweight: 23.9%, Normal weight: 14.4%, Overweight: 7.9%, and Obese: 9.0%, P < 0.001). After adjusting confounders, the excess mortality risk remained significant in the severely underweight group (HR, 2.32; 95%CI, 1.83–2.94; P < 0.001), and in the underweight group (HR, 1.31; 95%CI, 1.08–1.59; P = 0.005) relative to the normal weight group, while the lower mortality risk was no longer significant in the overweight group (HR, 0.82; 95%CI, 0.62–1.10; P = 0.18) and in the obese group (HR, 1.09; 95%CI, 0.65–1.85; P = 0.74). Very low BMI was associated with a higher risk for one-year mortality after discharge in patients with ADHF
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