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991.
Tao Yang Bin Kong Jian-Wen Gu Yong-Qin Kuang Lin Cheng Wen-Tao Yang Xun Xia Hai-Feng Shu 《Cellular and molecular neurobiology》2014,34(6):797-804
Experimental studies have demonstrated significant secondary damage (including cell apoptosis, blood–brain barrier disruption, inflammatory responses, excitotoxic damage, and free radical production) after traumatic brain injury (TBI). Quercetin is a natural flavonoid found in high quantities in fruits and vegetables, and may be a potential antioxidant and free radical scavenger. The purpose of this study was to determine the effects of quercetin on TBI-induced upregulation of oxidative stress, inflammation, and apoptosis in adult Sprague–Dawley rats. Animals were subjected to Feeney’s weight-drop injury, thus inducing the parietal contusion brain injury model. Quercetin was administered (30 mg/kg intraperitoneal injection) 0, 24, 48, and 72 h after TBI. Quercetin reduced cognitive deficits, the number of TUNEL- and ED-1-positive cells, the protein expressions of Bax and cleaved-caspase-3 proteins, and the levels of TBARS and proinflammatory cytokines, and increased the activity of antioxidant enzymes (GSH-Px, SOD, and CAT) at 1 week after TBI. Our results suggest that in TBI rats, quercetin improves cognitive function owing to its neuroprotective action via the inhibition of oxidative stress, leading to a reduced inflammatory response, thereby reducing neuronal death. 相似文献
992.
Myokine IL-15 regulates the crosstalk of co-cultured porcine skeletal muscle satellite cells and preadipocytes 总被引:1,自引:0,他引:1
Yinghui Li Fengna Li Binbin Lin Xiangfeng Kong Yulong Tang Yulong Yin 《Molecular biology reports》2014,41(11):7543-7553
The present study was carried out to preliminarily reveal the underlying mechanisms of the co-culture system between porcine muscle satellite cells (SCs) and stromal-vascular cells (SVs). The two cell types were co-cultured to assess both proliferation and differentiation. Desmin and Pref-1 immunofluorescence staining technique were taken to identify the two types of isolated cells. The expression of specific marker genes Myogenin was up-regulated in SCs (P < 0.05) and the differentiation of SCs could be promoted when co-cultured with preadipocytes compared with the single-cultured control, while expression of c/EBPβ in SVs was down-regulated (P < 0.05) and the differentiation of preadipocytes could be inhibited. Furthermore, secretion of myokine IL-15 was markedly increased, as well as its gene and protein expression levels in co-culture supernatants. However, the secretion of adipokine leptin was significantly decreased. These findings demonstrate that myokines like IL-15 could facilitate the SCs’ differentiation while inhibit the SVs differentiation, and act as an important regulator of co-culture between muscle cells and adipocytes. 相似文献
993.
Zhen Yang Fanxiang Kong Xiaoli Shi Yang Yu Min Zhang 《Journal of applied phycology》2014,26(4):1669-1674
In this study, Microcystis aeruginosa was cultivated in a P-limited and P-replete culture medium and exposed to artificial UV-B radiation to investigate the interactive effect of UV-B exposure and phosphorus limitation on this harmful alga. After 15 days, both UV-B exposure and phosphorus limitation led to a significant decline in pigment content (phycocyanin and carotene) and photosynthetic activity (F v/F m and ETRmax), and the impact was most pronounced when the two conditions were combined. Due to the interactive effect, P-limited M. aeruginosa under UV-B exposure exhibited the lowest cell density compared to the other treatments. These results suggest that phosphorus limitation increases the stress of UV-B radiation in Microcystis. In other words, high-level UV-B radiation has higher growth inhibitory on Microcystis in P-limited lakes than in P-replete lakes. 相似文献
994.
Scott A. Merkle Paul M. Montello Hannah M. Reece Lisheng Kong 《Trees - Structure and Function》2014,28(6):1767-1776
Key message
Embryogenic cultures of eastern and Carolina hemlocks could be initiated, and somatic embryos and plantlets produced using standard conifer protocols and media. Embryogenic hemlock cultures were cryostored and recovered.Abstract
Eastern hemlock (Tsuga canadenesis) and Carolina hemlock (Tsuga caroliniana) are threatened with extirpation from their native ranges in eastern North America by the introduction of the hemlock woolly adelgid (HWA; Adelges tsugae), an exotic insect pest that has already killed millions of hemlock trees. Efforts to conserve and restore these members of the Pinaceae could be greatly enhanced by the availability of an in vitro propagation system. We conducted experiments to initiate embryogenic cultures from eastern and Carolina hemlock zygotic embryos at different stages of development using three media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-Benzylaminopurine (BA). Cone collection date, medium and source tree had significant effects on induction of embryogenic tissue from zygotic embryo explants of both species, which ranged as high as 52 % for eastern hemlock and 17 % for Carolina hemlock. Embryogenic hemlock cultures could be cryostored using a protocol employing sorbitol and DMSO, and recovered following several months of frozen storage. Transfer of embryogenic tissue from proliferation media containing 2, 4-D and BA to a Litvay medium with abscisic acid promoted the development of somatic embryos, which were stimulated to mature by slow drying under semi-permeable plastic film. Embryos moved to an imbibition-germination medium without plant growth regulators and incubated in the light elongated and subsequently germinated. A small number of germinated embryos survived transfer to ex vitro conditions and grew into somatic seedlings. The embryogenesis and cryostorage systems developed in the study are already being integrated with hemlock breeding efforts to develop clones with resistance or tolerance to HWA. 相似文献995.
Lina Kong Yu Liang Lumin Qin Lei Sun Guangmin Xia Shuwei Liu 《Development genes and evolution》2014,224(4-6):189-196
The Ns genome of the genus Psathyrostachys possesses superior traits useful for wheat improvement. However, very little is known about the high molecular weight (HMW) subunits of glutenin encoded by the Ns genome. In this paper, we report the isolation of four alleles of HMW glutenin subunit gene from Psathyrostachys juncea. Sequence alignment data shows the four alleles have similar primary structure with those in wheat and other wheat-related grasses, with some unique modifications. All four sequences more closely resemble y-type, rather than x-type, glutenins. However, our results show three of the subunits (1Ns2-4) contain an extra glutamine residue in the N-terminal region not found on typical y-type subunits, as well as the x-type subunit specific sequence LAAQLPAMCRL. These three subunits likely represent an intermediate state in the divergence between x- and y-type subunits. Results also indicate that the Ns genome is more closely related to the St genome of Pseudoroegneria than any other Triticeae genomes. 相似文献
996.
997.
Daphnia (water fleas) are small crustaceans that undergo an unusual switch from asexual to sexual reproduction that is dependent on environmental conditions. In this study, a senescence-associated protein (SAP) from the common freshwater species Daphnia pulex was cloned using primers based on homologous sequences and rapid amplification of cDNA ends (RACE). Real-time PCR was employed to quantify the expression of D. pulex SAP (DpSAP) in individual organisms. The role of DpSAP in the reproductive transformation was further investigated in both parthenogenetic and sexual females by using digoxin-labeled SAP RNA probes and RNA whole-mount in situ hybridization. DpSAP was more highly expressed in sexual females, indicating a role in growth and reproduction. Cellular localization studies using RNA whole-mount in situ hybridization showed specific expression in the second tentacle joints. These expression patterns suggest an important role for DpSAP in the reproductive transformation of D. pulex. 相似文献
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999.
1000.
Batch‐to‐Batch Variation of Polymeric Photovoltaic Materials: its Origin and Impacts on Charge Carrier Transport and Device Performances 下载免费PDF全文
Harrison Ka Hin Lee Zhao Li Iordania Constantinou Franky So Sai Wing Tsang Shu Kong So 《Liver Transplantation》2014,4(16)
A detailed investigation of the impact of molecular weight distribution of a photoactive polymer, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), on photovoltaic device performance and carrier transport properties is reported. It is found that different batches of as‐received polymers have substantial differences in their molecular weight distribution. As revealed by gel permeation chromatography (GPC), two peaks can generally be observed. One of the peaks corresponds to a high molecular weight component and the other peak corresponds to a low molecular weight component. Photovoltaic devices fabricated with a higher proportion of low molecular weight component have power conversion efficiencies (PCEs) reduced from 5.7% to 2.5%. The corresponding charge carrier mobility at the short‐circuit region is also significantly reduced from 2.7 × 10?5 to 1.6 × 10?8 cm2 V?1 s?1. The carrier transport properties of the polymers at various temperatures are further analyzed by the Gaussian disorder model (GDM). All polymers have similar energetic disorders. However, they appear to have significant differences in carrier hopping distances. This result provides insight into the origin of the molecular weight effect on carrier transport in polymeric semiconducting materials. 相似文献