711 research outputs found
Towards an assay for allelic inactivation of vomeronasal receptor genes in mouse
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Biology, 1998.Includes bibliographical references (leaves 17-19).by Tien-Yi Lee.S.M
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Endothelial toll-like receptor 4 maintains lung integrity via epigenetic suppression of p16INK4a.
We previously reported that the canonical innate immune receptor toll-like receptor 4 (TLR4) is critical in maintaining lung integrity. However, the molecular mechanisms via which TLR4 mediates its effect remained unclear. In the present study, we identified distinct contributions of lung endothelial cells (Ec) and epithelial cells TLR4 to pulmonary homeostasis using genetic-specific, lung- and cell-targeted in vivo methods. Emphysema was significantly prevented via the reconstituting of human TLR4 expression in the lung Ec of TLR4-/- mice. Lung Ec-silencing of TLR4 in wild-type mice induced emphysema, highlighting the specific and distinct role of Ec-expressed TLR4 in maintaining lung integrity. We also identified a previously unrecognized role of TLR4 in preventing expression of p16INK4a , a senescence-associated gene. Lung Ec-p16INK4a -silencing prevented TLR4-/- induced emphysema, revealing a new functional role for p16INK4a in lungs. TLR4 suppressed endogenous p16INK4a expression via HDAC2-mediated deacetylation of histone H4. These findings suggest a novel role for TLR4 in maintaining of lung homeostasis via epigenetic regulation of senescence-related gene expression
Taiwanese parents’ perspectives on young children’s use of information communication technology
IntroductionHow parents think and feel about their children’s use of technology can influence how their kids behave online. The family’s socioeconomic status (SES) may also affect this influence. In light of this, this research emphasizes the need for more investigation into parental attitudes and the role of SES in shaping how children consume media.MethodsThis study surveyed 629 Taiwanese parents to explore their attitudes toward their young children’s use of information communication technology (ICT), usage patterns, and the interplay with socioeconomic status.ResultsThe findings revealed a significant disconnect: although approximately 50% of parents considered above six years old to be a suitable age for children to start ICT, over 80% of children had already engaged with ICT before that age, indicating a large disparity between parental expectations and actual initiation. Furthermore, parents highlighted “learning interest” and “various content” as the most positive impacts of children’s ICT use, while “addiction and overreliance” emerged as their primary concern. Notably, parents, as a whole, tended to perceive their child’s ICT use more negative than positively, with fathers displaying greater acceptance of negative viewpoints than mothers. Parental attitudes toward children’s ICT use were categorized into five clusters, ranging from balanced and optimistic views to value emphasis, conservatism, and negative doubts. This classification underscores the intricate and multifaceted nature of parental perspectives, encompassing both positive and negative outlooks on children’s ICT utilization.DiscussionThe findings underscore the nuanced character of parents’ attitudes toward technology, shaped by the intricacies and challenges posed by the digital era. These insights emphasize that parental attitudes go beyond a simplistic positive-negative divide, reflecting a comprehensive response to the opportunities and complexities inherent in the digital age
Antidiabetic effect and mode of action of cytopiloyne
Cytopiloyne was identified as a novel polyacetylenic compound. However, its antidiabetic properties are poorly understood. The aim of the present study was to investigate the anti-diabetic effect and mode of action of cytopiloyne on type 2 diabetes (T2D). We first evaluated the therapeutic effect of cytopiloyne on T2D in db/db mice. We found that one dose of cytopiloyne reduced postprandial glucose levels while increasing blood insulin levels. Accordingly, long-term treatment with cytopiloyne reduced postprandial blood glucose levels, increased blood insulin, improved glucose tolerance, suppressed the level of glycosylated hemoglobin A1c (HbA1c), and protected pancreatic islets in db/db mice. Next, we studied the anti-diabetic mechanism of action of cytopiloyne. We showed that cytopiloyne failed to decrease blood glucose in streptozocin- (STZ-)treated mice whose β cells were already destroyed. Additionally, cytopiloyne dose dependently increased insulin secretion and expression in β cells. The increase of insulin secretion/expression of cytopiloyne was regulated by protein kinase C α (PKC α ) and its activators, calcium, and diacylglycerol (DAG). Overall, our data suggest that cytopiloyne treats T2D via regulation of insulin production involving the calcium/DAG/PKC α cascade in β cells. These data thus identify the molecular mechanism of action of cytopiloyne and prove its therapeutic potential in T2D
Effects of Angelica dahurica
The main objective of wound treatments is to restore the functional skin properties and prevent infection. Traditional Chinese medicine provides alternative anti-inflammatory, antimicrobial, and wound healing therapies. Both Angelica dahurica extract (AE) and Rheum officinale extract (RE) possess antimicrobial activity. In this study, AE and RE were applied in wound treatment to investigate their healing effects. Thirty Sprague-Dawley rats with dorsal full-thickness skin excision were divided into normal saline (NS), AE, RE, AE plus RE (ARE), and Biomycin (BM) groups. The treatment and area measurement of wounds were applied daily for 21 days. Wound biopsies and blood samples were obtained for histology examinations and cytokine analysis. Results showed that wound contraction in ARE group was significantly higher than that in NS and BM groups (P 0.05), and plasma TGF-β1 levels were significantly lower than those in the NS group on days 3-4 (P < 0.05). In conclusion, ARE accelerates wound healing during inflammation and proliferation phases
High ambient-contrast-ratio display using tandem reflective liquid crystal display and organic light-emitting device
A high ambient-contrast-ratio (A-CR) and large aperture-ratio display is conceptually demonstrated and experimentally validated by stacking a normally black reflective liquid crystal display (NB-RLCD) and an organic light-emitting device (OLED). Such a tandem device can be switched between the NB-RLCD mode and the OLED mode under bright and dark ambient light, respectively. The normally black characteristic of the RLCD also helps to boost the A-CR under OLED-mode operation. To obtain a better image quality in the RLCD mode, a bumpy and transmissive structure is used to eliminate the specular reflection and to increase the viewing angle performance that results in CR \u3e 2:1 over 55 degrees viewing cone. Besides, such a structure can also increase the external quantum efficiency of the OLED by 49.4%. In our experiments, regardless of the ambient intensity the A-CR is kept higher than 100:1
An Extract of Antrodia camphorata Mycelia Attenuates the Progression of Nephritis in Systemic Lupus Erythematosus-Prone NZB/W F1 Mice
Antrodia camphorata is used in folk medicine for the treatment of inflammation syndromes and liver-related diseases in Taiwan. The goal of this study was to evaluate the efficacy of the mycelial extract of A. camphorata (ACE) for the treatment of systemic lupus erythematosus (SLE) in SLE-prone NZB/W F1 mice. After antibodies against double-stranded DNA appeared in NZB/W mice, the mice were orally administered varying dosages of ACE (100, 200 and 400 mg kg−1) for 5 consecutive days per week for 12 weeks via gavage. To assess the efficacy of ACE, we measured SLE-associated biochemical and histopathological biomarkers levels of blood urine nitrogen (BUN), blood creatinine, urine protein and urine creatinine and thickness of the kidney glomerular basement membrane by staining with periodic acid-Schiff. Antroquinonol, an active component of ACE, was investigated for anti-inflammation activity in lipopolysaccharide-induced RAW 267.4 cells. ACE at 400 mg kg−1 significantly suppressed urine protein and serum BUN levels and decreased the thickness of the kidney glomerular basement membrane. Antroquinonol significantly inhibited the production of tumor necrosis factor-α and interleukin-1β by 75 and 78%, respectively. In conclusion, ACE reduced urine protein and creatinine levels and suppressed the thickening of the kidney glomerular basement membrane, suggesting that ACE protects the kidney from immunological damage resulting from autoimmune disease
Nona-Arginine Facilitates Delivery of Quantum Dots into Cells via Multiple Pathways
Semiconductor quantum dots (QDs) have recently been used to deliver and monitor biomolecules, such as drugs and proteins. However, QDs alone have a low efficiency of transport across the plasma membrane. In order to increase the efficiency, we used synthetic nona-arginine (SR9), a cell-penetrating peptide, to facilitate uptake. We found that SR9 increased the cellular uptake of QDs in a noncovalent binding manner between QDs and SR9. Further, we investigated mechanisms of QD/SR9 cellular internalization. Low temperature and metabolic inhibitors markedly inhibited the uptake of QD/SR9, indicating that internalization is an energy-dependent process. Results from both the pathway inhibitors and the RNA interference (RNAi) technique suggest that cellular uptake of QD/SR9 is predominantly a lipid raft-dependent process mediated by macropinocytosis. However, involvement of clathrin and caveolin-1 proteins in transducing QD/SR9 across the membrane cannot be completely ruled out
A Flexible PMN-PT Ribbon-Based Piezoelectric-Pyroelectric Hybrid Generator for Human-Activity Energy Harvesting and Monitoring
The rapid advancements of wearable electronics require continued innovation in sustainable power sources and human interactive sensors. An abundance of energy in various forms, such as mechanical, thermal, optical, and sound, are ubiquitous in the environment and human activities. Hybrid generators using piezoelectric polymers with relatively low piezoelectric and pyroelectric constants have been fabricated to simultaneously scavenge mechanical and thermal energies. In this work, micropatterned single-crystal (1-x)Pb(Mg,Nb)O3-xPbTiO3 (PMN-PT) ribbons, which possess excellent piezoelectric and pyroelectric properties, are utilized to build human activities energy harvesting and monitoring systems. The flexible PMN-PT ribbon-based sensor conformally attached on the surface of human skin enables high sensitivity for human body motions and can detect acoustic sounds precisely. The sensor has been used for monitoring temperature-related activities, caused for instance by warm water flow and even light illumination. The multifunctional performance of the PMN-PT ribbon-based hybrid generator shows great potential for self-powered wearable and human activities monitoring devices. This is the peer reviewed version of the following article: Chen, Y. et al.: A Flexible PMN-PT Ribbon-Based Piezoelectric-Pyroelectric Hybrid Generator for Human-Activity Energy Harvesting and Monitoring. In: Advanced Electronic Materials (2017), which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/aelm.201600540/abstract. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.DFG/DI 2013/2-1BMBF/Q.Com-H/16KIS010
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