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991.
Potassium and phosphorus transport and signaling in plants 总被引:2,自引:0,他引:2
Nitrogen(N), potassium(K), and phosphorus(P) are essential macronutrients for plant growth and development, and their availability affects crop yield. Compared with N, the relatively low availability of K and P in soils limits crop production and thus threatens food security and agricultural sustainability. Improvement of plant nutrient utilization efficiency provides a potential route to overcome the effects of K and P deficiencies. Investigation of the molecular mechanisms underlying how plants sense, absorb, transport, and use K and P is an important prerequisite to improve crop nutrient utilization efficiency. In this review, we summarize current understanding of K and P transport and signaling in plants, mainly taking Arabidopsis thaliana and rice(Oryza sativa) as examples. We also discuss the mechanisms coordinating transport of N and K, as well as P and N. 相似文献
992.
993.
Michael A.P. Bloomfield Tinya Chang Maximillian J. Woodl Laura M. Lyons Zhen Cheng Clarissa Bauer‐Staeb Catherine Hobbs Sophie Bracke Helen Kennerley Louise Isham Chris Brewin Jo Billings Talya Greene Glyn Lewis 《World psychiatry》2021,20(1):107-123
Experiencing psychological trauma during childhood and/or adolescence is associated with an increased risk of psychosis in adulthood. However, we lack a clear knowledge of how developmental trauma induces vulnerability to psychotic symptoms. Understanding the psychological processes involved in this association is crucial to the development of preventive interventions and improved treatments. We sought to systematically review the literature and combine findings using meta‐analytic techniques to establish the potential roles of psychological processes in the associations between developmental trauma and specific psychotic experiences (i.e., hallucinations, delusions and paranoia). Twenty‐two studies met our inclusion criteria. We found mediating roles of dissociation, emotional dysregulation and post‐traumatic stress disorder (PTSD) symptoms (avoidance, numbing and hyperarousal) between developmental trauma and hallucinations. There was also evidence of a mediating role of negative schemata, i.e. mental constructs of meanings, between developmental trauma and delusions as well as paranoia. Many studies to date have been of poor quality, and the field is limited by mostly cross‐sectional research. Our findings suggest that there may be distinct psychological pathways from developmental trauma to psychotic phenomena in adulthood. Clinicians should carefully ask people with psychosis about their history of developmental trauma, and screen patients with such a history for dissociation, emotional dysregulation and PTSD symptoms. Well conducted research with prospective designs, including neurocognitive assessment, is required in order to fully understand the biopsychosocial mechanisms underlying the association between developmental trauma and psychosis. 相似文献
994.
Khanh B. Tran Gregory Gimenez Peter Tsai Sharada Kolekar Euan J. Rodger Aniruddha Chatterjee Anower Jabed Jen‐Hsing Shih Wayne R. Joseph Elaine S. Marshall Qian Wang Cristin G. Print Michael R. Eccles Bruce C. Baguley Peter R. Shepherd 《Pigment cell & melanoma research》2021,34(1):136-143
Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions. 相似文献
995.
996.
Beatriz Mello Qiqing Tao Jose Barba‐Montoya Sudhir Kumar 《Molecular ecology resources》2021,21(1):122-136
Simultaneous molecular dating of population and species divergences is essential in many biological investigations, including phylogeography, phylodynamics and species delimitation studies. In these investigations, multiple sequence alignments consist of both intra‐ and interspecies samples (mixed samples). As a result, the phylogenetic trees contain interspecies, interpopulation and within‐population divergences. Bayesian relaxed clock methods are often employed in these analyses, but they assume the same tree prior for both inter‐ and intraspecies branching processes and require specification of a clock model for branch rates (independent vs. autocorrelated rates models). We evaluated the impact of a single tree prior on Bayesian divergence time estimates by analysing computer‐simulated data sets. We also examined the effect of the assumption of independence of evolutionary rate variation among branches when the branch rates are autocorrelated. Bayesian approach with coalescent tree priors generally produced excellent molecular dates and highest posterior densities with high coverage probabilities. We also evaluated the performance of a non‐Bayesian method, RelTime, which does not require the specification of a tree prior or a clock model. RelTime's performance was similar to that of the Bayesian approach, suggesting that it is also suitable to analyse data sets containing both populations and species variation when its computational efficiency is needed. 相似文献
997.
Ee Xien Ng Ming Wang Shu Hui Neo Ching Ann Tee Chia-Hung Chen Krystyn J. Van Vliet 《Biotechnology journal》2021,16(3):2000048
Microcarriers are synthetic particles used in bioreactor-based cell manufacturing of anchorage-dependent cells to promote proliferation at efficient physical volumes, mainly by increasing the surface area-to-volume ratio. Mesenchymal stromal cells (MSCs) are adherent cells that are used for numerous clinical trials of autologous and allogeneic cell therapy, thus requiring avenues for large-scale cell production at efficiently low volumes and cost. Here, a dissolvable gelatin-based microcarrier is developed for MSC expansion. This novel microcarrier shows comparable cell attachment efficiency and proliferation rate when compared to several commercial microcarriers, but with higher harvesting yield due to the direct dissolution of microcarrier particles and thus reduced cell loss at the cell harvesting step. Furthermore, gene expression and in vitro differentiation suggest that MSCs cultured on gelatin microcarriers maintain trilineage differentiation with similar adipogenic differentiation efficiency and higher chondrogenic and osteogenic differentiation efficiency when compared to MSCs cultured on 2D planar polystyrene tissue culture flask; on the contrary, MSCs cultured on conventional microcarriers appear to be bipotent along osteochondral lineages whereby adipogenic differentiation potential is impeded. These results suggest that these gelatin microcarriers are suitable for MSC culture and expansion, and can also potentially be extended for other types of anchorage-dependent cells. 相似文献
998.
Sanna Loppi Paula Korhonen Maria Bouvy‐Liivrand Simone Caligola Tiia A. Turunen Mikko P. Turunen Ana Hernandez de Sande Natalia Koosowska Flavia Scoyni Anna Rosell Teresa García‐Berrocoso Sighild Lemarchant Hiramani Dhungana Joan Montaner Jari Koistinaho Katja M. Kanninen Minna U. Kaikkonen Rosalba Giugno Merja Heinniemi Tarja Malm 《Aging cell》2021,20(1)
999.
1000.
Ng Chu Xin Le Cheng Foh Tor Yin Sim Lee Sau Har 《International journal of peptide research and therapeutics》2021,27(4):2757-2775
International Journal of Peptide Research and Therapeutics - Bioactive peptides have emerged as promising therapeutic alternatives in pharmaceutical industry, especially to fight cancer. Here we... 相似文献