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671.
Zhi-Ran Yang Zhi-Gao Chen Zhong-He Ji Yu-Lin Lin Jue Zhang Ru Ma Zhao Li Xi Jiang Qian Chen Xue-Mei Du Yan Li 《Experimental Animals》2021,70(2):225
Malignant peritoneal mesothelioma (MPM) is a rare malignancy with few experimental models. This study used the human surgical specimen to establish MPM patient-derived xenograft (PDX) models and primary cell lines to provide a study platform for MPM in vitro and in vivo, and conducted histopathological analysis. Our study used the experimental peritoneal cancer index (ePCI) score to evaluate gross pathology, and the results showed that the ePCI score of the female and male nude mice were 8.80 ± 1.75 and 9.20 ± 1.81 (P=0.6219), respectively. The Hematoxylin and eosin (HE) staining of animal models showed that the tumor was epithelioid mesothelioma and invaded multiple organs. Immunohistochemistry (IHC) staining showed that Calretinin, Cytokeratin 5/6, WT-1 and Ki-67 were all positive. The Swiss-Giemsa and Immunofluorescence (IF) staining of primary cell lines were also consistent with the pathological characteristics of mesothelioma. We also performed the whole-exome sequencing (WES) to identify the mutant genes between models and the patient. And the results showed that 21 mutant genes were shared between the two groups, and the genes related to tumorigenesis and development including BAP1, NF2, MTBP, NECTIN2, CDC23, LRPPRC, TRIM25, and DHRS2. In conclusion, the PDX models and primary cell lines of MPM were successfully established with the epithelioid mesothelioma identity confirmed by histopathological evidence. Moreover, our study has also illustrated the shared genomic profile between models and the patient. 相似文献
672.
Biofloc Technology: Emerging Microbial Biotechnology for the Improvement of Aquaculture Productivity
MAMDOH T. JAMAL MOHAMMED BROOM BANDAR A. AL-MUR MAMDOUH AL HARBI MOHAMMED GHANDOURAH AHMED AL OTAIBI MD FAZLUL HAQUE 《Polish journal of microbiology》2020,69(4):401
With the significant increases in the human population, global aquaculture has undergone a great increase during the last decade. The management of optimum conditions for fish production, which are entirely based on the physicochemical and biological qualities of water, plays a vital role in the prompt aquaculture growth. Therefore, focusing on research that highlights the understanding of water quality and breeding systems’ stability is very important. The biofloc technology (BFT) is a system that maximizes aquaculture productivity by using microbial biotechnology to increase the efficacy and utilization of fish feeds, where toxic materials such as nitrogen components are treated and converted to a useful product, like a protein for using as supplementary feeds to the fish and crustaceans. Thus, biofloc is an excellent technology used to develop the aquaculture system under limited or zero water exchange with high fish stocking density, strong aeration, and biota. This review is highlighted on biofloc composition and mechanism of system work, especially the optimization of water quality and treatment of ammonium wastes. In addition, the advantages and disadvantages of the BFT system have been explained. Finally, the importance of contemporary research on biofloc systems as a figure of microbial biotechnology has been emphasized with arguments for developing this system for better production of aquaculture with limited natural resources of water.Key words: biofloc, BFT, aquaculture, microbes, water quality, wastes 相似文献
673.
Expression of a wild eggplant ribosomal protein L13a in potato enhances resistance to Verticillium dahliae 总被引:1,自引:0,他引:1
Liu Yang Chao Xie Wang Li Ruijie Zhang Dengwei Jue Qing Yang 《Plant Cell, Tissue and Organ Culture》2013,115(3):329-340
The ribosomal protein L13a was recently found to play a role not only in protein synthesis, but also in modulating translation. We reported in previous study that L13a was responsive to Verticillium dahliae (V. dahliae) infection in a highly resistant eggplant species (Solanum torvum, SW). To elucidate the possible role of L13a in V. dahliae infection, we cloned and characterized its cDNA (designated StoL13a) in this study. StoL13a encodes a protein of 23.46 kDa and shows a high similarity to the L13a from other plants. Phylogenetic analysis revealed that StoL13a clearly grouped with L13a-like sequences. Expression level of StoL13a altered in response to V. dahliae infection and phytohormone treatment. We expressed StoL13a in V. dahliae sensitive potato, and found that the transgenic potato plants were more resistant to V. dahliae infection than the control plants with disease index of 15–25.2. The transgenic plants showed a lower quantity of reactive oxygen species and attenuated oxidative injury. Also, six defense and antioxidant enzyme genes were up-regulated in the StoL13a ectopic expression plants. These results suggest that the StoL13a plays a role in plant defense to V. dahliae infection. 相似文献
674.
As the need for data processing and communication increases, and likewise, as the number of processing cores placed on a given single chip increases, improving the performance of interconnection networks is vital. In the present work, traditional topologies are re-examined. Torus is shown to be a good structure in terms of average latency and symmetry. When using torus in combination with high process levels, it is possible to design new, yet asymmetrical topologies that can meet the high communication performance requirements of many-core processors and also suit a large variety of traffic patterns. Firstly, this paper presents two novel and torus-like topologies called xtorus and xxtorus, which are evaluated by using both theoretical analysis and experimental simulation methods. For theoretical analysis, an algorithm for computing link path diversity and link entropy is given. The analysis shows that, compared with mesh, xmesh and torus, the proposed topologies have better properties in terms of diameter, average latency, throughput, and path diversity. Although more links are added, the number of links is of the same order of magnitude with that of mesh, xmesh, and torus. Proposed topologies also take advantage of increasingly higher levels of the VLSI process. Simulations on GEM5 reveal that xtorus has better scalability, and that its average latency is less than that of mesh, xmesh and torus by significant proportions respectively, particularly when the network scale is larger. Moreover, for different traffic patterns, its performance swing is less than that of mesh. Furthermore, in the present work, the proposed topologies are both asymmetrical and based on the entropy difference of the links in the topology. A strategy for heterogeneous link design is presented, which enables designers to trade off between delay, power and area according to a concrete integrated circuit design scene. 相似文献
675.
676.
677.
Jue Tao Lim Kenwin Maung Sok Teng Tan Suan Ee Ong Jane Mingjie Lim Joel Ruihan Koo Haoyang Sun Minah Park Ken Wei Tan Joanne Yoong Alex R. Cook Borame Sue Lee Dickens 《PLoS computational biology》2021,17(5)
Mass gathering events have been identified as high-risk environments for community transmission of coronavirus disease 2019 (COVID-19). Empirical estimates of their direct and spill-over effects however remain challenging to identify. In this study, we propose the use of a novel synthetic control framework to obtain causal estimates for direct and spill-over impacts of these events. The Sabah state elections in Malaysia were used as an example for our proposed methodology and we investigate the event’s spatial and temporal impacts on COVID-19 transmission. Results indicate an estimated (i) 70.0% of COVID-19 case counts within Sabah post-state election were attributable to the election’s direct effect; (ii) 64.4% of COVID-19 cases in the rest of Malaysia post-state election were attributable to the election’s spill-over effects. Sensitivity analysis was further conducted by examining epidemiological pre-trends, surveillance efforts, varying synthetic control matching characteristics and spill-over specifications. We demonstrate that our estimates are not due to pre-existing epidemiological trends, surveillance efforts, and/or preventive policies. These estimates highlight the potential of mass gatherings in one region to spill-over into an outbreak of national scale. Relaxations of mass gathering restrictions must therefore be carefully considered, even in the context of low community transmission and enforcement of safe distancing guidelines. 相似文献
678.
DONG Jian YANG Li SU Tao YANG XueDong CHEN Bin ZHANG Jue WANG XiaoYing JIANG XueXiang 《中国科学C辑(英文版)》2013,(8):745-750
The kidneys are essential for maintaining homeostasis,are responsible for the reabsorption of water,glucose and amino acids,and filter the blood by removing waste.Acute kidney injury(AKI) is a syndrome characterized by the rapid loss of renal excretory function and the accumulation of end metabolic products of urea and creatinine.AKI is associated with the later development of chronic kidney disease and end-stage kidney disease,and may eventually be fatal.Early diagnosis of AKI and assessments of the effects of treatment,however,are challenging.The pathophysiological mechanism of AKI is thought to be the imbalance between oxygen supply and demand in the kidneys.We have assessed the ability of arterial spin labeling(ASL) perfusion magnetic resonance imaging(MRI),without the administration of contrast media,to quantify renal blood flow(RBF) non-invasively.We found that RBF was significantly lower in AKI patients than in healthy volunteers.These results suggest that ASL perfusion MRI,a noninvasive measurement of RBF,may be useful in the early diagnosis of AKI. 相似文献
679.
AL. Ionescu 《Biologia Plantarum》1969,11(5):370-374
In experiments with double-hybrid maize grown in the field and in a greenhouse, we analysed the value of the suction force as related to the regime of irrigation. The results showed that the level of water supply to the plants is in good connection with the value of the suction force and the coefficient H (the relative degree of water saturation of the cells) analysed at the same time. In the case of the 2 hybrids under investigation the highest value of coefficient H was found to be between 35–48. The data indicate that the use of these two indices should take part in a physiological method for the settlement and the application of water rules in irrigation. 相似文献
680.
N Okazaki X X Jue H Miyake M Kuroda T Shimamoto T Tsuchiya 《Journal of bacteriology》1997,179(13):4443-4445
We detected inducible melibiose transport activity in cells of Enterobacter cloacae IID977. H+, but not Na+, was found to be the coupling cation for this transporter. We cloned and sequenced the gene encoding the melibiose transporter. A homology search of a protein sequence database revealed that this melibiose transporter has high sequence similarity with the lactose transporter (LacY) and the raffinose transporter (RafB) and has some similarity with the melibiose transporter (MelB) of Escherichia coli. 相似文献