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11.
A suitable bioreactor system for large scale embryo-to-plantlets conversion of Kalopanax septemlobus was established. In temporary immersion with net (TIN) bioreactor, 85% of embryos successfully produced plantlets whereas in continuous immersion with net (CIN) bioreactor, only conversion rate of 29.3% was obtained. Embryos cultured in TIN bioreactor produced more vigorous plantlets in terms of fresh weight, height, root length, roots and leaves quantity. In CIN bioreactor, Kalopanax plantlets showed high malondialdehyde (MDA) content and increased activities of reactive oxygen species (ROS)-processing enzymes, such as ascorbate peroxidase (APX) and glutathione reductase (GR) indicating the occurrence of oxidative stress. However, superoxide dismutase (SOD) and catalase (CAT) showed similar activities in plantlets grown in different bioreactors. Kalopanax plantlets grown in both TIN and CIN bioreactors were harvested and transferred to greenhouse for their acclimatization. Plantlets grown in CIN bioreactor exhibited low survival rate (75.8%) compared to those grown in TIN bioreactor (100%). MDA content decreased with progression of acclimatization indicating a decrease in oxidative stress. However, MDA level in CIN derived plantlets was higher than TIN derived plantlets. In TIN derived plantlets, an increase in SOD and GR activities were observed after 1 week and thereafter decreased. CAT activity decreased while APX activity started to increase after 1 week of acclimatization. The results indicated that Kalopanax plantlets were able to overcome oxidative stress mainly through SOD activity. However, levels of antioxidant enzyme activities were higher in CIN derived plantlets than TIN derived plantlets. Kalopanax plantlets obtained from TIN bioreactor performed better during the acclimatization phase and showed higher survival rate than material obtained on CIN bioreactor or conventional culture systems.  相似文献   
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Trypanosomatid parasites are responsible for various human diseases, such as sleeping sickness, animal trypanosomiasis, or cutaneous and visceral leishmaniases. The few available drugs to fight related parasitic infections are often toxic and present poor efficiency and specificity, and thus, finding new molecular targets is imperative. Aminoacyl-tRNA synthetases (aaRSs) are essential components of the translational machinery as they catalyze the specific attachment of an amino acid onto cognate tRNA(s). In trypanosomatids, one gene encodes both cytosolic- and mitochondrial-targeted aaRSs, with only three exceptions. We identify here a unique specific feature of aaRSs from trypanosomatids, which is that most of them harbor distinct insertion and/or extension sequences. Among the 26 identified aaRSs in the trypanosome Leishmania tarentolae, 14 contain an additional domain or a terminal extension, confirmed in mature mRNAs by direct cDNA nanopore sequencing. Moreover, these RNA-Seq data led us to address the question of aaRS dual localization and to determine splice-site locations and the 5′-UTR lengths for each mature aaRS-encoding mRNA. Altogether, our results provided evidence for at least one specific mechanism responsible for mitochondrial addressing of some L. tarentolae aaRSs. We propose that these newly identified features of trypanosomatid aaRSs could be developed as relevant drug targets to combat the diseases caused by these parasites.  相似文献   
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The association between adipose tissue and immunity has been established and fat-associated lymphoid clusters (FALCs) are considered as a source of immune cells. We discovered lymphoid clusters (LCs) in mouse mediastinal fat tissues (MFTs). In Th1-biased C57BL/6N (B6), Th2-biased DBA/2Cr (DBA) and autoimmune-prone MRL/MpJ (MRL) mice strains, LCs without a fibrous capsule and germinal center were observed in white-colored MFTs extending from the diaphragm to the heart. The number and size of the LCs were larger in 12-month-old mice than in 3-month-old mice in all of the examined strains. Moreover, B6 had an especially large number of LCs compared with DBA and MRL. The immune cells in the LCs consisted of mainly T-cells and some B-cells. The majority of T-cells were CD4+ helper T (Th) cells, rather than CD8+ cytotoxic T-cells and no obvious immune cell population difference was present among the strains. Furthermore, high endothelial venules and lymphatic vessels in the LCs were better developed in B6 mice than in the other strains. Interestingly, some CD133+ hematopoietic progenitor cells and some c-Kit+/CD127+ natural helper cells were detected in the LCs. BrdU+ proliferating cells were more abundant in the LCs of B6 mice than in the LCs of the other strains and the number of BrdU+ cells increased with age. This is the first report of LCs in mouse MFTs. We suggest that the mouse genetic background affects LC size and number. We term the LCs “mediastinal fat-associated lymphoid clusters”. These clusters can be considered as niches for Th cell production.  相似文献   
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Breast cancer (BC) is the most frequently occurring malignancy in women worldwide. Despite the substantial advancement in understanding the molecular mechanisms and management of BC, it remains the leading cause of cancer death in women. One of the main reasons for this obstacle is that we have not been able to find the Achilles heel for the BC as a highly heterogeneous disease. Accumulating evidence has revealed that noncoding RNAs (ncRNAs), play key roles in the development of BC; however, the involving of complex regulatory interactions between the different varieties of ncRNAs in the development of this cancer has been poorly understood. In the recent years, the newly discovered mechanism in the RNA world is “competing endogenous RNA (ceRNA)” which proposes regulatory dialogues between different RNAs, including long ncRNAs (lncRNAs), microRNAs (miRNAs), transcribed pseudogenes, and circular RNAs (circRNAs). In the latest BC research, various studies have revealed that dysregulation of several ceRNA networks (ceRNETs) between these ncRNAs has fundamental roles in establishing the hallmarks of BC development. And it is thought that such a discovery could open a new window for a better understanding of the hidden aspects of breast tumors. Besides, it probably can provide new biomarkers and potential efficient therapeutic targets for BC. This review will discuss the existing body of knowledge regarding the key functions of ceRNETs and then highlights the emerging roles of some recently discovered ceRNETs in several hallmarks of BC. Moreover, we propose for the first time the “ceRnome” as a new term in the present article for RNA research.  相似文献   
16.
Saudi Arabian camels {Camelus dromedarius) are infected with three species of Eimeria: E. dromedarii (28.4%), E. rajasthani < 22.2%), and E. cameli (19.2%); 41.6% of the animals examined were positive. The highest prevalence of infection was reported in the western region of the country. Mixed infection with two Eimeria species is most common; E. dromedarii was most frequently and generally the most predominant species. Eimeria dromedarii and E. rajasthani are described for the first time from Saudi Arabian camels.  相似文献   
17.
In this paper, we report the realization of highly confined mid-infrared plasmon modes by coupling freestanding graphene-coated nanowire with a dielectric substrate. It is shown that the presence of a nearby dielectric substrate not only breaks the azimuthal symmetry of the plasmon modes but also has a strong impact on the coupling and hybridization of these modes. The degree of interactions with the substrate depends on the permittivity of the substrate, the key structural parameters of the nanowire, the operation frequency and chemical potential of graphene, as well as the gap distance between the nanowire and supporting substrate. It is found that compared to freestanding case, using a high-index substrate and adjusting the gap distance can result in the following benefits: (i) an ultra-small mode area and a long propagation length can be realized simultaneously, (ii) a stronger field enhancement in the low-index gap region and improved figure of merit can be achieved, and (iii) a huge reduction in the crosstalk can be made which is crucial for the realization of high-density integrated nanophotonic devices.  相似文献   
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The effects of statin treatment in the setting of heart failure have already been shown. Nevertheless, there is little knowledge about its influence on adrenergic pathways in cardiomyocytes. Therefore, this study investigated the impact of cerivastatin on adrenoceptor-mediated signalling pathways in isolated adult ventricular cardiomyocytes. It focused on two endpoints: hypertrophic growth and TGFbeta expression. Cultured cardiomyocytes were used to study rac activation (analysed by its translocation into the membrane fraction), ROS formation (H(2)DCF fluorescence) and hypertrophic growth ((14)C-phenylalanine incorporation). Alpha- and beta-adrenoceptor stimulation showed significant differences regarding rac activation, ROS formation, and p38 MAP kinase activation. Both alpha- and beta-adrenoceptor stimulation induced TGFbeta expression. Upon activation of alpha-adrenergic signalling - although ROS formation was not influenced by cerivastatin - TGFbeta expression decreased. Following beta stimulation, TGFbeta expression as well as rac and p38 MAP kinase activation were reduced after pre-treatment with cerivastatin. Statin treatment did not show any influence on hypertrophic growth. In summary, this study clearly demonstrates the ability of adrenoceptor stimulation to increase TGFbeta expression. One component of the beneficial effects of statin therapy on heart failure might therefore be due to a dominant reduction and inhibition of TGFbeta, which is involved in many pathophysiological processes in cardiomyocytes.  相似文献   
20.
A rhamnolipid producing bacterium,Pseudomonas aeruginosa HR was isolated from south of Iranian oil wells. In the previous study, effects of main factors of cultivation on production of biosurfactant by this strain were evaluated and their optimized values were determined. In the present paper, the ability of produced biosurfactant in oil recovery was investigated. For this purpose, its affect on enhanced oil recovery in sand pack and core holder obtained from oil wells was evaluated. It was found that the maximum oil recovery in saturated sand pack column and in saturated core holder of crude oil were 23.6 and 64%, respectively. Then, in core test mathematical model was proposed by considering interactions between given parameters. Furthermore, dependence of residual oil recovery on the process of core washing during injection of biosurfactant was investigated. Finally, capillary desaturation curve was compared with core flood data.  相似文献   
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