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排序方式: 共有1210条查询结果,搜索用时 15 毫秒
81.
Michal Kowara Sonia Borodzicz-Jazdzyk Karolina Rybak Maciej Kubik Agnieszka Cudnoch-Jedrzejewska 《International journal of molecular sciences》2021,22(11)
Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented. 相似文献
82.
Silvia Buonvino Matteo Ciocci Dror Seliktar Sonia Melino 《International journal of molecular sciences》2021,22(11)
Photo-polymerized hydrogels are ideally suited for stem-cell based tissue regeneration and three dimensional (3D) bioprinting because they can be highly biocompatible, injectable, easy to use, and their mechanical and physical properties can be controlled. However, photo-polymerization involves the use of potentially toxic photo-initiators, exposure to ultraviolet light radiation, formation of free radicals that trigger the cross-linking reaction, and other events whose effects on cells are not yet fully understood. The purpose of this study was to examine the effects of hydrogen sulfide (H2S) in mitigating cellular toxicity of photo-polymerization caused to resident cells during the process of hydrogel formation. H2S, which is the latest discovered member of the gasotransmitter family of gaseous signalling molecules, has a number of established beneficial properties, including cell protection from oxidative damage both directly (by acting as a scavenger molecule) and indirectly (by inducing the expression of anti-oxidant proteins in the cell). Cells were exposed to slow release H2S treatment using pre-conditioning with glutathione-conjugated-garlic extract in order to mitigate toxicity during the photo-polymerization process of hydrogel formation. The protective effects of the H2S treatment were evaluated in both an enzymatic model and a 3D cell culture system using cell viability as a quantitative indicator. The protective effect of H2S treatment of cells is a promising approach to enhance cell survival in tissue engineering applications requiring photo-polymerized hydrogel scaffolds. 相似文献
83.
Wrosch Carsten; Miller Gregory E.; Lupien Sonia; Pruessner Jens C. 《Canadian Metallurgical Quarterly》2008,27(6):685
Objective: This study examined whether the association between cortisol secretion and changes in physical health symptoms would depend on other factors in a person's life. The authors expected that physical health effects would emerge particularly when cortisol disturbances co-occur in the context of high levels of trait negative affect or poor sleep. Design: Physical symptoms, diurnal cortisol secretion, affective tendencies, and sleep efficiency were assessed in a 2-yr longitudinal study of 184 older adults. Main Outcome Measure: Two-year changes in physical symptoms. Results: High cortisol levels were associated with increases in physical symptoms, but only among participants who experienced high negative affect and poor sleep. Conclusion: Elevated levels of cortisol secretion contribute to older adults' physical symptoms if they co-occur in the context of other emotional and behavioral problems. By contrast, cortisol disturbances may not influence physical symptoms among people who are emotionally well or engage in efficient sleep behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
The MPEG- 2 Advanced Audio Coder is the latest issue of the MPEG audio encoders/decoders family, whose most popular version is known as MP3. It gathers many of the latest highly efficient sound compression techniques in a quite classically structured coder. The main part is based on a Discrete Cosine Transform with variable resolution. The output from this filterbank is compressed by the combination of an adaptive bit allocation module, according to frequency subbands, and a set of noiseless Huffman codebooks. Bit allocation is controlled by a psychoa-coustic model which determines an audibility threshold for signal distortion in the frequency domain. This article intends to explain the ISO standard without replacing it, and also to be a general introduction to perceptual audio coding. 相似文献
85.
Sonia Lpez Lía Hoz Eda Patricia Tenorio Beatriz Buentello Ftima Sofía Magaa Ana Wintergerst Alejandro Navas Yonathan Garfias Higinio Arzate 《International journal of molecular sciences》2021,22(11)
Human oral mucosa stem cells (hOMSCs) arise from the neural crest, they can self-renew, proliferate, and differentiate to several cell lines and could represent a good source for application in tissue engineering. Because of their anatomical location, hOMSCs are easy to isolate, have multilineage differentiation capacity and express embryonic stem cells markers such as—Sox2, Oct3/4 and Nanog. We have used SHEM (supplemented hormonal epithelial medium) media and cultured hOMSCs over human amniotic membrane and determined the cell’s capacity to differentiate to an epithelial-like phenotype and to express corneal specific epithelial markers—CK3, CK12, CK19, Pan-cadherin and E-cadherin. Our results showed that hOMSCs possess the capacity to attach to the amniotic membrane and express CK3, CK19, Pan-Cadherin and E-Cadherin without induction with SHEM media and expressed CK12 or changed the expression pattern of E-Cadherin to a punctual-like feature when treated with SHEM media. The results observed in this study show that hOMSCs possess the potential to differentiate toward epithelial cells. In conclusion, our results revealed that hOMSCs readily express markers for corneal determination and could provide the ophthalmology field with a therapeutic alternative for tissue engineering to achieve corneal replacement when compared with other techniques. Nevertheless, further studies are needed to develop a predictable therapeutic alternative for cornea replacement. 相似文献
86.
87.
Antonio C. Silva Sonia Mello-Castanho Francisco Guitian Isabel Montero Antonio Esteban-Cubillo Isabel Sobrados Jesus Sanz Jose S. Moya 《Journal of the American Ceramic Society》2008,91(4):1300-1305
In the present investigation, a glassing process for galvanic waste (GW) incorporation with a high chemical stability is presented. Glasses with up to 50 wt% of galvanic solid waste by modifications in the basic composition of soda–lime–borosilicate glasses were prepared. After fusing at temperatures up to 1300°C, the glasses were characterized by inductively coupled plasma, scanning electron microscopy/energy-dispersive X-ray spectroscopy, high-temperature microscopy, transmission and reflected light microscopy, nuclear magnetic resonance, X-ray photoelectron spectroscopy, and X-ray diffraction methods. The chemical stability was evaluated by hydrolytic attack assays. Glasses containing up to 40 wt% of GW with a very high chemical stability, similar to bottle glasses, were obtained. 相似文献
88.
Sage and rosemary essential oils versus BHT for the inhibition of lipid oxidative reactions in liver pâté 总被引:1,自引:0,他引:1
The antioxidant effect of two plant essential oils (sage and rosemary essential oils) and one synthetic antioxidant (BHT) on refrigerated stored liver pâté (4 °C/90 days) was evaluated. Pâtés with no added antioxidants were used as controls. Liver pâtés were analysed for the amount of polyunsaturated fatty acids (PUFA), thiobarbituric acid reactive substances (TBA-RS) numbers, and lipid-derived volatiles at days 0, 30, 60 and 90 of refrigerated storage. The amount of PUFA gradually decreased during refrigerated storage of porcine liver pâtés with this decrease being significantly greater (P<0.05) in control and BHT pâtés than in those with added essential oils. Consistently, the increase of TBA-RS numbers during refrigerated storage of liver pâtés was significantly higher in control pâtés than in the treated counterparts. At days 60 and 90, TBA-RS numbers in treated pâtés were significantly smaller (P<0.05) than in the control counterparts. Headspace solid-phase microextraction (HS-SPME) successfully isolated recognized indicators of lipid decomposition (i.e. hexanal, nonanal, hexan-1-ol, oct-1-en-3-ol, deca-(E,Z)-2,4-dienal) from liver pâtés whereas some other volatiles analysed are typical contributors to the overall off-flavour of oxidized liver (i.e. hept-(Z)-4-enal, non-(E)-2-enal, nona-(E,E)-2,4-dienal). The addition of antioxidants significantly (P<0.05) reduced the total amount of lipid-derived volatiles isolated from liver pâtés HS. Plant essential oils inhibited oxidative deterioration of liver pâtés to a higher extent than BHT did. 相似文献
89.
Michaela K. Back Sonia Ruggieri Eric Jacobi Jakob von Engelhardt 《International journal of molecular sciences》2021,22(12)
Onset and progression of Alzheimer’s disease (AD) pathophysiology differs between brain regions. The neocortex, for example, is a brain region that is affected very early during AD. NMDA receptors (NMDARs) are involved in mediating amyloid beta (Aβ) toxicity. NMDAR expression, on the other hand, can be affected by Aβ. We tested whether the high vulnerability of neocortical neurons for Aβ-toxicity may result from specific NMDAR expression profiles or from a particular regulation of NMDAR expression by Aβ. Electrophysiological analyses suggested that pyramidal cells of 6-months-old wildtype mice express mostly GluN1/GluN2A NMDARs. While synaptic NMDAR-mediated currents are unaltered in 5xFAD mice, extrasynaptic NMDARs seem to contain GluN1/GluN2A and GluN1/GluN2A/GluN2B. We used conditional GluN1 and GluN2B knockout mice to investigate whether NMDARs contribute to Aβ-toxicity. Spine number was decreased in pyramidal cells of 5xFAD mice and increased in neurons with 3-week virus-mediated Aβ-overexpression. NMDARs were required for both Aβ-mediated changes in spine number and functional synapses. Thus, our study gives novel insights into the Aβ-mediated regulation of NMDAR expression and the role of NMDARs in Aβ pathophysiology in the somatosensory cortex. 相似文献
90.