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11.
Guozhen Liu Changjie Yan Wenxue Zhai Ping He Jiang Yang Xiaobing Li Lihuang Zhu 《中国科学C辑(英文版)》1999,42(2):162-170
Homeobox genes, widely distributed among animal and plant kingdoms, play an important role in developmental process. Several homeobox conserved fragments were amplified by PCR and the flanking regions were also obtained by an LM-PCR procedure. Sequencing and Southern analysis showed that they belong to a homeobox gene family of rice. Six homeobox-containing fragments were mapped on the molecular linkage map of rice. They were located on chromosomes 3, 4 and 7 respectively. It is noteworthy that there are 4 homeobox fragments located on rice chromosome 3 and the result is also consistent with the comparative genomics between rice and maize. 相似文献
12.
The unique physicochemical properties of (2D) nanomaterials make them well‐suited for use in sustainable energy applications. Many of these materials can be further improved with vacancy engineering. This review details recent progress in the vacancy engineering of ultrathin 2D nanomaterials. For clarity, it mainly focuses on various ultrathin 2D materials in three categories: Xa&XaYb‐, MaXb‐, or MaXbYc‐structured materials. Recently developed vacancies in different types of ultrathin 2D materials, as well as their preparation and characterization, are described. Emphasis is placed on the potential electrochemical energy storage and conversion applications of these materials. This review considers the relationship between vacancy properties and material categories of various ultrathin 2D materials in terms of application requirements, preparation, and characterization techniques. The challenges and future outlook of this promising field are summarized. 相似文献
13.
Yunzhen Wu Shuyan Cao Jungang Hou Zhuwei Li Bo Zhang Panlong Zhai Yanting Zhang Licheng Sun 《Liver Transplantation》2020,10(29)
Converting CO2 to valuable carbonaceous fuels and chemicals via electrochemical CO2 reduction by using renewable energy sources is considered to be a scalable strategy with substantial environmental and economic benefits. One of the challenges in this field is to develop nanocatalysts with superior electrocatalytic activity and selectivity for targeted products. Nonmetal species modification of nanocatalysts is of great significance for the construction of distinctive active sites to overcome the kinetic limitations of CO2 reduction. These types of modification enable the efficient control of the selectivity and significantly decrease the reaction overpotential. Herein, a comprehensive review of the recent progress of nonmetal species modification of nanocatalysts for electrochemical CO2 reduction is presented. After discussing some fundamental parameters and the basic principles of CO2 reduction, including possible reaction pathways in light of theoretical modeling and experiments, the identification of active sites and elucidation of reaction mechanisms are emphasized for unraveling the role of nonmetal species modification, such as heteroatom incorporation, organic molecule decoration, electrolyte engineering, and single‐atom engineering. In the final section, future challenges and constructive perspectives are provided, facilitating the accelerated advancement of mechanism research and practical applications of green carbon cycling. 相似文献
14.
Fanli Zeng Yanan Meng Zhimin Hao Pan Li Weibo Zhai Shen shen Zhiyan Cao Jingao Dong 《Molecular Plant Pathology》2020,21(3):401-414
Eukaryotic organisms activate conserved signalling networks to maintain genomic stability in response to DNA genotoxic stresses. However, the coordination of this response pathway in fungal pathogens remains largely unknown. In the present study, we investigated the mechanism by which the northern corn leaf blight pathogen Setosphaeria turcica controls maize infection and activates self-protection pathways in response to DNA genotoxic insults. Appressorium-mediated maize infection by S. turcica was blocked by the S-phase checkpoint. This repression was dependent on the checkpoint central kinase Ataxia Telangiectasia and Rad3 related (ATR), as inhibition of ATR activity or knockdown of the ATR gene recovered appressorium formation in the presence of genotoxic reagents. ATR promoted melanin biosynthesis in S. turcica as a defence response to stress. The melanin biosynthesis genes StPKS and StLac2 were induced by the ATR-mediated S-phase checkpoint. The responses to DNA genotoxic stress were conserved in a wide range of phytopathogenic fungi, including Cochliobolus heterostrophus, Cochliobolus carbonum, Alternaria solani, and Alternaria kikuchiana, which are known causal agents for plant diseases. We propose that in response to genotoxic stress, phytopathogenic fungi including S. turcica activate an ATR-dependent pathway to suppress appressorium-mediated infection and induce melanin-related self-protection in addition to conserved responses in eukaryotes. 相似文献
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16.
Purpose: Cervical cancer (CC) is one of the most general gynecological malignancies and is associated with high morbidity and mortality. We aimed to select candidate genes related to the diagnosis and prognosis of CC.Methods: The mRNA expression profile datasets were downloaded. We also downloaded RNA-sequencing gene expression data and related clinical materials from TCGA, which included 307 CC samples and 3 normal samples. Differentially expressed genes (DEGs) were obtained by R software. GO function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs were performed in the DAVID dataset. Using machine learning, the optimal diagnostic mRNA biomarkers for CC were identified. We used qRT-PCR and Human Protein Atlas (HPA) database to exhibit the differences in gene and protein levels of candidate genes.Results: A total of 313 DEGs were screened from the microarray expression profile datasets. DNA methyltransferase 1 (DNMT1), Chromatin Assembly Factor 1, subunit B (CHAF1B), Chromatin Assembly Factor 1, subunit A (CHAF1A), MCM2, CDKN2A were identified as optimal diagnostic mRNA biomarkers for CC. Additionally, the GEPIA database showed that the DNMT1, CHAF1B, CHAF1A, MCM2 and CDKN2A were associated with the poor survival of CC patients. HPA database and qRT-PCR confirmed that these genes were highly expressed in CC tissues.Conclusion: The present study identified five DEmRNAs, including DNMT1, CHAF1B, CHAF1A, MCM2 and Kinetochore-related protein 1 (KNTC1), as potential diagnostic and prognostic biomarkers of CC. 相似文献
17.
Su-Fang Niu Yun Zhai Ren-Xie Wu Zhen-Bang Liang Hao-Ran Zhang Zhong-Lu Li Qi Qiu Ling-Li Zhou 《Zeitschrift fur angewandte Ichthyologie》2021,37(2):308-313
Trachurus japonicus is an economically important fish in the northwestern Pacific Ocean. However, its resources have declined seriously and there is an urgent need for a wide-range of investigations of the existing genetic resources. This requires a large number of diverse molecular markers with high discriminating power. In this study, we identified 43,264 perfect SSRs in T. japonicus genome using SLAF-seq technology. Of these, we randomly selected 106 SSRs (tri-nucleotide to hexa-nucleotide) to test for polymorphism. Eventually, we successfully developed a total of 33 loci including 8 tri-nucleotide and 25 long repeat motifs (tetra-nucleotide to hexa-nucleotide). The number of alleles (Na) of these loci ranged from 4 to 24 (mean 12.6). The observed heterozygosity (Ho) and expected heterozygosity (He) varied from 0.258 to 0.969 (mean 0.723) and from 0.452 to 0.962 (mean 0.827), respectively. All loci except TJ6-7 were highly informative (PIC > 0.5). These results showed that the shortlisted 33 loci exhibited moderate to relatively high genetic diversity, of which 18 were regarded as highly polymorphic and well-resolved. In summary, these diverse and potential microsatellites detected in our study provide substantial genetic basis for the screening of polymorphic SSR markers of T. japonicus and also provide a powerful tool to perform further studies on the genetic resource assessment and conservation of T. japonicus. 相似文献
18.
Joshua Havumaki Ted Cohen Chengwei Zhai Joel C. Miller Seth D. Guikema Marisa C. Eisenberg Jon Zelner 《PLoS computational biology》2021,17(2)
There is an emerging consensus that achieving global tuberculosis control targets will require more proactive case finding approaches than are currently used in high-incidence settings. Household contact tracing (HHCT), for which households of newly diagnosed cases are actively screened for additional infected individuals is a potentially efficient approach to finding new cases of tuberculosis, however randomized trials assessing the population-level effects of such interventions in settings with sustained community transmission have shown mixed results. One potential explanation for this is that household transmission is responsible for a variable proportion of population-level tuberculosis burden between settings. For example, transmission is more likely to occur in households in settings with a lower tuberculosis burden and where individuals mix preferentially in local areas, compared with settings with higher disease burden and more dispersed mixing. To better understand the relationship between endemic incidence levels, social mixing, and the impact of HHCT, we developed a spatially explicit model of coupled household and community transmission. We found that the impact of HHCT was robust across settings of varied incidence and community contact patterns. In contrast, we found that the effects of community contact tracing interventions were sensitive to community contact patterns. Our results suggest that the protective benefits of HHCT are robust and the benefits of this intervention are likely to be maintained across epidemiological settings. 相似文献
19.
Shasha Song Zhi Geng Shutao Zhai Jie Xu Gang Hou Xinbao Zhang 《Cell biochemistry and biophysics》2013,66(2):347-350
Sleep adaptation in an unfamiliar environment, the so-called “first-night effect”, is known to occur in healthy individuals. To avoid the confounding effects of the “first-night effect”, the first-night sleep data are not used in most of sleep studies. In the present study, we examined changes of sleep adaptation in hospitalized patients with depression. Polysomnographic recordings were obtained for two consecutive nights from 14 patients, and sleep parameters were compared between both nights. Total sleep time, sleep latency, awakening times, movement awakening time, sleep efficiency, sleep architecture, rapid eye movement (REM) sleep latency, REM intensity, REM density, REM time, REM cycles, and other indicators showed no significant difference (p > 0.05) between the first and second nights. To conclude, hospitalized patients with depression have relatively less change in sleep adaptation, thus, the data from their first night do not need to be discarded. 相似文献
20.
Abstract A novel approach to 2′-O-alkylpyrimidine nucleosides involving a 3′- hydroxyl assisted intramolecular delivery of a divalent metal alkoxide leads to a regiospecific opening of the anhydropyrimidine linkage at the 2′-position. Thus, reaction of 5′-protected 2,2′-anhydrouridine with magnesium or calcium alkoxides in DMF affords exclusively the corresponding 2′-O-alkyluridines in reasonable yields. 相似文献