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991.
Yumi Yamanashi Migaku Teramoto Naruki Morimura Etsuko Nogami Satoshi Hirata 《Primates; journal of primatology》2018,59(2):145-152
Understanding how social relationships affect long-term stress is important because stress has a profound impact on the welfare of animals and social relationships often exert a strong influence on their stress responses. The purpose of this study was to investigate the relationship between social behaviors and long-term stress levels as assessed by hair cortisol (HC) concentration. The subjects were 11 chimpanzees living in an all-male group (divided into two sub-groups) in Kumamoto Sanctuary, Kyoto University, Japan. Behavioral data were collected between December 2014 and March 2015. The total observation time was 129 h. Hair samples were collected in late March and early April 2015, and cortisol was extracted from the hair and measured with enzyme immunoassay. The hair growth rate was estimated to be 1.33 ± 0.06 cm/month. The results revealed that there was a positive correlation between the rate of receiving aggression and HC levels. We also found a significant negative correlation between the balance between giving and receiving grooming (grooming balance index: GBI), which was calculated by subtracting the rate with which grooming is given from that with which it is received, and the rate of receiving aggression and between the GBI and HC levels. Thus, individuals receiving higher levels of aggression also tended to give grooming for relatively long periods compared to the time they were being groomed. In contrast, the rate of initiating aggression did not have a relationship with either HC levels or any measure of social grooming. We did not find social buffering effects, as there was no correlation between mutual social grooming and HC levels. These results show that not only aggressive interactions but also overall social situations in which animals do not have balanced relationships with others might result in the long-term elevation of cortisol levels in captive male chimpanzees. 相似文献
992.
Establishing a dual knock-out cell line by lentivirus based combined CRISPR/Cas9 and Loxp/Cre system
Ya Li Weifeng Zhang Junli Zhao Sai Li Linlin Shan Jiuling Zhu Yan Li He Zhu Qinwen Mao Haibin Xia 《Cytotechnology》2018,70(6):1595-1605
The clustered regulatory interspersed short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system has been widely used for gene knock-out. Lentiviral vectors have been commonly used as a delivery method for this system, however, prolonged Cas9/sgRNA expression due to lentiviral integration can lead to accumulating off-target mutations. To solve this issue in engineering a gene knock-out cell line, this study established a novel system, which was composed of two lentiviral vectors. One lentiviral vector carried simultaneously sgRNAs and CRISPR/Cas9 expression cassettes targeting single or multiple gene(s); the other lentiviral vector carried Cre that could remove excess sgRNAs and Cas9 expression cassettes in the genome after gene targeting was achieved. To prove the principle, two candidate genes, extracellular matrix protein 1 (ECM1) and progranulin (PGRN), both highly expressed in MDA-MB-231 cells, were selected for testing the novel system. A dual knock-out of ECM1 and PGRN was successfully achieved in MDA-MB-231 cell line, with the sgRNAs and Cas9 expression cassettes being removed by Cre. This system should have great potential in applications for multiple genes knock-out in vitro. 相似文献
993.
Thaiany Quevedo Melo Sjef J. C. V. M. Copray Merari F. R. Ferrari 《Neurochemical research》2018,43(12):2212-2223
Parkinson’s disease (PD) is characterized by the presence of insoluble protein clusters containing α-synuclein. Impairment of mitochondria, endoplasmic reticulum, autophagy and intracellular trafficking proper function has been suggested to be caused by α-synuclein toxicity, which is also associated with the higher levels of ROS found in the aged brain and in PD. Oxidative stress leads to protein oligomerization and aggregation that impair autophagy and mitochondrial dynamics leading to a vicious cycle of organelles damage and neurodegeneration. In this review we focused on the role of α-synuclein dysfunction as a cellular stressor that impairs mitochondria, endoplasmic reticulum, autophagy and cellular dynamics culminating with dopaminergic depletion and the pathogenesis of PD. 相似文献
994.
Tropical forests are paramount in regulating the global carbon cycle due to the storage of large amounts of carbon in their biomass. Using repeat censuses of permanent plots located at 15 sites in the Andes Mountains of northwest Colombia, we evaluate: (1) the relationship between aboveground biomass (AGB) stocks, AGB dynamics (mortality, productivity, and net change), and changes in temperature across a ca. 3000-m elevational gradient (≈?16.1 °C); (2) how AGB mortality and AGB productivity interact to determine net AGB change; and (3) the extent to which either fine-grain (0.04-ha) or coarse-grain (1-ha) processes determine the AGB dynamics of these forests. We did not find a significant relationship between elevation/temperature and biomass stocks. The net AGB sequestered each year by these forests (2.21?±?0.51 Mg ha?1 year?1), equivalent to approximately 1.09% of initial AGB, was primarily determined by tree growth. Both forest structural properties and global warming influenced AGB mortality and net change. AGB productivity increases with greater inequality of tree sizes, a pattern characteristic of forest patches recovering from disturbances. Overall, we find that global warming is triggering directional changes in species composition by thermophilization via increased tree mortality of species in the lower portions of their thermal ranges and that the inclusion of small-scale forest structural changes can effectively account for endogenous processes such as changes in forest structure. The inclusion of fine-grain processes in assessments of AGB dynamics could provide additional insights about the effects that ongoing climate change has on the functioning of tropical montane forests. 相似文献
995.
Jianmin Chen Weiyue Huang Ziyao Huang Shiqi Liu Yaling Ye Qinglian Li Meiping Huang 《AAPS PharmSciTech》2018,19(3):1141-1151
Dissolving microneedles (MNs) offered a simple, minimally invasive method for meloxicam (MX) delivery to the skin. However, the fabrication of dissolving MNs still faced some challenges, such as significant time consumption, loss of drug activity, and difficulty in regulating MN drug loading. To address these issues, we developed the tip-dissolving (TD) MNs. Several kinds of drugs were encapsulated successfully, and the quantity of MX ranged from 37.23?±?8.40 to 332.53?±?13.37 μg was precisely controlled. The effects of fabrication process on biomacromolecules stability were studied, and it was found that tyrosinase kept 90.4% activity during the fabrication process. The whole process for the fabrication of MNs only takes approximately 1 h. In order to further evaluate the potential of the TD MNs, MX TD MNs were prepared for in vitro release experiments, in vivo release experiments, safety evaluation, pharmacokinetic studies, and pharmacodynamic studies. The results demonstrated that MX TD MNs offered several advantages, including rapid release of the encapsulated drug (91.72% within 30 min), efficient drug delivery to skin (79.18%), no obvious skin irritation, decent relative bioavailability (122.3%), and strong anti-inflammatory and analgesic effects. Based on these results, we envisage that the TD MNs have promising potential for transdermal drug delivery of MX. 相似文献
996.
The endoplasmic reticulum (ER) plays essential roles indispensable for cellular activity and survival, including functions such as protein synthesis, secretory and membrane protein folding, and Ca2+ release in cells. The ER is sensitive to stresses that can lead to the aggregation and accumulation of misfolded proteins, which eventually triggers cellular dysfunction; severe or prolonged ER stress eventually induces apoptosis. ER stress-induced apoptosis causes several devastating diseases such as atherosclerosis, neurodegenerative diseases, and diabetes. In addition, the production of biopharmaceuticals such as monoclonal antibodies requires the maintenance of normal ER functions to achieve and maintain the production of high-quality products in good quantities. Therefore, it is necessary to develop methods to efficiently relieve ER stress and protect cells from ER stress-induced apoptosis. The silkworm storage protein 1 (SP1) has anti-apoptotic activities that inhibit the intrinsic mitochondrial apoptotic pathway. However, the role of SP1 in controlling ER stress and ER stress-induced apoptosis has not been investigated. In this paper, we demonstrate that SP1 can inhibit apoptosis induced by a well-known ER stress inducer, thapsigargin, by alleviating the decrease in cell viability and mitochondrial membrane potential. Interestingly, SP1 significantly blocked increases in CHOP and GRP78 expression as well as ER Ca2+ leakage into the cytosol following ER stress induction. This indicates that SP1 protects cells from ER stressinduced apoptosis by functioning as an upstream inhibitor of apoptosis. Therefore, studying SP1 function can offer new insights into protecting cells against ER stress-induced apoptosis for future applications in the biopharmaceutical and medicine industries. 相似文献
997.
Anh Duc Nguyen In Yeub Hwang Jeon Young Chan Eun Yeol Lee 《Biotechnology and Bioprocess Engineering》2016,21(4):477-482
One-carbon feedstock such as methanol and formate has attracted much attention as carbon substrate of industrial biotechnology for production of value-added chemicals and biofuels. Productivity improvement of natural one-carbon metabolic pathways in native hosts such as methanotrophs is somewhat difficult due to inefficient genetic tools and low specific growth rate. As an alternative, metabolic engineering can create new and efficient metabolic pathways of one-carbon substrate that can be readily transferred to non-native hosts. In this paper, recent progresses in protein and metabolic engineering for creation of methanol and formate-utilizing synthetic pathways based on RuMP cycle and formolase are reviewed. Perspectives on one-carbon metabolic pathway engineering in non-native host are also discussed. 相似文献
998.
Earthworms and arbuscular mycorrhizal fungi (AMF) have profound impacts on plant performance. However, it is largely unknown
if and how earthworms and AMF may affect plant succession. We planted mesocosms with an early-mid successional and a mid-late
successional grassland plant community and added endogeic earthworms and commercial AMF in a full-factorial way to natural
background soil. Earthworms had a positive effect on the total root and shoot biomass of both plant communities, with the
effect on the shoots being slightly enhanced by co-inoculation with AMF. Surprisingly, the earthworm effect on the mid successional
plant species depended on the successional stage of the plant community. Earthworms had a positive effect on the mid successional
plant species when they were growing in the mid-late successional plant community, but no effect when the same plant species
were growing in the early-mid successional plant community. Addition of AMF alone tended to reduce the shoot biomass of the
early successional plant species, while the addition of earthworms in the presence or absence of AMF increased their shoot
biomass. We conclude that the impacts of earthworms on plant species may depend on the successional stage of the plant community,
while the effect of AMF addition depends on the successional stage of the plant community and may be changed by the presence
of earthworms. Earthworms and AMF addition affect plants and plant communities of different successional stages differently
with potential effects on plant succession. 相似文献
999.
Hee Jin Park Hyeong Cheol Park Sang Yeol Lee Hans J. Bohnert Dae-Jin Yun 《Journal of Plant Biology》2011,54(5):275-285
Posttranslational modifications of proteins by small polypeptides including ubiquitination, neddylation (related to ubiquitin
(RUB) conjugation), and sumoylation are implicated in plant growth and development, and they regulate protein degradation,
location, and interaction with other proteins. Ubiquitination mediates the selective degradation of proteins by the ubiquitin
(Ub)/proteasome pathway. The ubiquitin-like protein RUB is conjugated to cullins, which are part of a ubiquitin E3 ligase
complex that is involved in auxin hormonal signaling. Sumoylation, by contrast, is known for its involvement in guiding protein
interactions related to abiotic and biotic stresses and in the regulation of flowering time. ATG8/ATG12-mediated autophagy
influences degradation and recycling of cellular components. Other ubiquitin-like modifiers (ULPs) such as homology to Ub-1,
ubiquitin-fold modifier 1, and membrane-anchored Ub-fold are also found in Arabidopsis. ULPs share similar three-dimensional structures and a conjugation system, including E1 activating enzymes, E2 conjugation
enzymes, and E3 ligases, as well as proteases for deconjugation and recycling of the tags. However, each of the ULP posttranslational
modifications possesses its own specific enzymes and modifies its specific targets selectively. This review discusses recent
findings on ubiquitination and ubiquitin-like modifier processes and their roles in the posttranslational modification of
proteins in Arabidopsis. 相似文献
1000.
Dawei Jiang Yunchao Liu Aiping Wang Gaiping Zhang Guoyu Yang Yumei Chen Pengchao Ji Chang Liu Yapeng Song Yunfang Su Guoqiang Wang Jucai Wang Baolei Zhao Ruiguang Deng 《Biotechnology letters》2016,38(6):901-908