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951.
Yue Zhou Zhexu Guo Zhonghua Wu Jinxin Shi Cen Zhou Jie Sun Iko Hidasa Xuefei Lu Chong Lu 《Translational oncology》2021,14(1)
BackgroundPatients with locally advanced rectal cancer (LARC) are more likely to suffer local recurrence and distant metastases, contributing to worse prognoses. Considering the provided dramatic reduction of local recurrences, neoadjuvant CRT (nCRT) followed by curative resection with total mesorectal excision (TME) and adjuvant chemotherapy has been established as standard therapy for LARC patients. However, the efficacy of adding bevacizumab in neoadjuvant therapy, especially in induction therapy-containing nCRT for LARC patients remains uncertain.MaterialsPubMed, Embase, and Web of Science were searched to retrieve records on the application of bevacizumab in a neoadjuvant setting for LARC patients. The endpoints of interest were pCR and the rates of patients suffering Grade 3/4 bevacizumab-specific adverse events, namely bleeding, wound healing complications, and gastrointestinal perforation.Results29 cohorts covering 1134 subjects were included in this systematic review. The pooled pCR rate for bevacizumab-relevant cohorts was 21% (95% confidence interval (95% CI), 17–25%; I2 = 61.8%), the pooled estimates of Grade 3/4 bleeding, Grade 3/4 wound healing complication, Grade 3/4 gastrointestinal perforation were 1% (95% CI, 0–3%; I2 = 0%), 2% (95% CI, 1–5%; I2 = 4.7%), and 2% (95% CI, 0–5%; I2 = 0%), respectively.ConclusionThe addition of bevacizumab in the nCRT, especially in the TNT, for LARC patients provides promising efficacy and acceptable safety. However, the results should be interpreted cautiously due to the small amount of relevant data and need further confirmation by future studies. 相似文献
952.
953.
Jing Zhang Mingjian Zhou Zhenglin Ge Jie Shen Can Zhou Cecilia Gotor Luis C. Romero Xingliang Duan Xin Liu Deliang Wu Xianchao Yin Yanjie Xie 《Plant, cell & environment》2020,43(3):624-636
Recent studies have demonstrated that hydrogen sulfide (H2S) produced through the activity of l -cysteine desulfhydrase (DES1) is an important gaseous signaling molecule in plants that could participate in abscisic acid (ABA)-induced stomatal closure. However, the coupling of the DES1/H2S signaling pathways to guard cell movement has not been thoroughly elucidated. The results presented here provide genetic evidence for a physiologically relevant signaling pathway that governs guard cell in situ DES1/H2S function in stomatal closure. We discovered that ABA-activated DES1 produces H2S in guard cells. The impaired guard cell ABA phenotype of the des1 mutant can be fully complemented when DES1/H2S function has been specifically rescued in guard cells and epidermal cells, but not mesophyll cells. This research further characterized DES1/H2S function in the regulation of LONG HYPOCOTYL1 (HY1, a member of the heme oxygenase family) signaling. ABA-induced DES1 expression and H2S production are hyper-activated in the hy1 mutant, both of which can be fully abolished by the addition of H2S scavenger. Impaired guard cell ABA phenotype of des1/hy1 can be restored by H2S donors. Taken together, this research indicated that guard cell in situ DES1 function is involved in ABA-induced stomatal closure, which also acts as a pivotal hub in regulating HY1 signaling. 相似文献
954.
Ascaris lumbricoides and Ascaris suum are parasitic nematodes living in the small intestine of humans and pigs, and can cause the disease ascariasis. For long, there has been controversy as to whether the two ascaridoid taxa represent the same species due to their significant resemblances in morphology. However, the complete mitochondrial (mt) genome data have been lacking for A. lumbricoides in spite of human and animal health significance and socio-economic impact globally of these parasites. In the present study, we sequenced the complete mt genomes of A. lumbricoides and A. suum (China isolate), which was 14,303 bp and 14,311 bp in size, respectively. The identity of the mt genomes was 98.1% between A. lumbricoides and A. suum (China isolate), and 98.5% between A. suum (China isolate) and A. suum (USA isolate). Both genomes are circular, and consist of 36 genes, including 12 genes for proteins, 2 genes for rRNA and 22 genes for tRNA, which are consistent with that of all other species of ascaridoid studied to date. All genes are transcribed in the same direction and have a nucleotide composition high in A and T (71.7% for A. lumbricoides and 71.8% for A. suum). The AT bias had a significant effect on both the codon usage pattern and amino acid composition of proteins. Phylogenetic analyses of A. lumbricoides and A. suum using concatenated amino acid sequences of 12 protein-coding genes, with three different computational algorithms (Bayesian analysis, maximum likelihood and maximum parsimony) all clustered in a clade with high statistical support, indicating that A. lumbricoides and A. suum was very closely related. These mt genome data and the results provide some additional genetic evidence that A. lumbricoides and A. suum may represent the same species. The mt genome data presented in this study are also useful novel markers for studying the molecular epidemiology and population genetics of Ascaris. 相似文献
955.
956.
Kai Fang Jie Zhou Lin Chen Yu-Xuan Li Ai-Ling Yang Xing-Fan Dong Han-Bo Zhang 《PLoS pathogens》2021,17(7)
The virulence evolution of multiple infections of parasites from the same species has been modeled widely in evolution theory. However, experimental studies on this topic remain scarce, particularly regarding multiple infections by different parasite species. Here, we characterized the virulence and community dynamics of fungal pathogens on the invasive plant Ageratina adenophora to verify the predictions made by the model. We observed that A. adenophora was highly susceptible to diverse foliar pathogens with mixed vertical and horizontal transmission within leaf spots. The transmission mode mainly determined the pathogen community structure at the leaf spot level. Over time, the pathogen community within a leaf spot showed decreased Shannon diversity; moreover, the vertically transmitted pathogens exhibited decreased virulence to the host A. adenophora, but the horizontally transmitted pathogens exhibited increased virulence to the host. Our results demonstrate that the predictions of classical models for the virulence evolution of multiple infections are still valid in a complex realistic environment and highlight the impact of transmission mode on disease epidemics of foliar fungal pathogens. We also propose that seedborne fungi play an important role in structuring the foliar pathogen community from multiple infections within a leaf spot. 相似文献
957.
Hua Zhang XiaoBing Xiang BenGen Zhou JianFa Chen YouQiang Sun ShuangXiao Zhang AiHua Li Jie Li 《Journal of biochemical and molecular toxicology》2023,37(5):e23306
Osteoarthritis (OA) is the most common age-related joint disease characterized by chronic inflammation, progressive articular cartilage destruction, and subchondral sclerosis. Accumulating evidence suggests that circular RNAs (circRNAs) play key roles in OA, but the function of circSLTM in OA remains greatly unknown. Therefore, this study focused on interleukin-1β (IL-1β)-treated primary human chondrocytes as well as a rat model to investigate the expression pattern and functional role of circSLTM in OA in vitro and in vivo. CircSLTM and high mobility group protein B2 (HMGB2) were upregulated in IL-1β-induced chondrocytes, whereas miR-421 was downregulated. Knockdown of circSLTM or overexpression of miR-421 ameliorated IL-1β-induced chondrocyte apoptosis and inflammation. The regulatory relationship between circSLTM and miR-421, as well as that between miR-421 and HMGB2, was predicted by bioinformatics and then verified by the RNA immunoprecipitation experiment and dual-luciferase reporter gene assay. Furthermore, silencing of circSLTM increased cartilage destruction and decreased cartilage tissue apoptosis rate and inflammation in a rat model of OA. Taken together, our findings demonstrate the fundamental role of circSLTM in OA progression and provide a potential molecular target for OA therapy. 相似文献
958.
Understanding the Impact of Oligomeric Polystyrene Side Chain Arrangement on the All‐Polymer Solar Cell Performance 下载免费PDF全文
Kevin L. Gu Yan Zhou Hongping Yan Cheng Wang Ging‐Ji Nathan Wang Michael F. Toney Zhenan Bao 《Liver Transplantation》2018,8(2)
The introduction of oligomeric polystyrene (PS) side chains into the conjugated backbone is proven to enhance the processability and electronic properties of semiconducting polymers. Here, two series of donor and acceptor polymers are prepared with different molar percentages of PS side chains to elucidate the effect of their substitution arrangement on the all‐polymer solar cell performance. The observed device performance is lower when the PS side chains are substituted on the donor polymer and higher when on the acceptor polymer, indicating a clear arrangement effect of the PS side chain. The incorporation of PS side chains to the acceptor polymer contributes to the decrease in phase separation domain size in the blend films. However, the reduced domain size was still an order of magnitude larger than the typical exciton diffusion length. A detailed morphological study together with the estimation of solubility parameter of the pristine PS, donor, and acceptor polymers reveals that the relative value of solubility parameter of each component dominantly contributes to the purity of the phase separated domain, which strongly impacts the amount of generated photocurrent and overall solar cell performance. This study provides an understanding of the design strategies to improve the all‐polymer solar cells. 相似文献
959.
Minghua Zhou Bo Zhu Nicolas Brüggemann Jessica Bergmann Yanqiang Wang Klaus Butterbach-Bahl 《Ecosystems》2014,17(2):286-301
Guaranteeing high crop yields while reducing environmental impacts of nitrogen fertilizer use due to associated losses of N2O emissions and nitrate (NO3 ?) leaching is a key challenge in the context of sustainable intensification of crop production. However, few field data sets are available that explore the effect of different forms of N management on yields as well as on N losses in the form of N2O or NO3 ?. Here we report on a large-scale field lysimeter (8 × 4 m2) experiment, which was designed to determine soil CH4 and N2O emissions, NO3 ? leaching losses and crop yields from a subtropical rain-fed wheat–maize rotation in the Sichuan Basin, one of the most intensively used agricultural regions in China. One control and three different fertilizer treatments with the same total rate of N application (280 kg N ha?1 y?1) were included: NF: control (no fertilizer); NPK: synthetic N fertilizer; OMNPK: synthetic N fertilizer plus pig manure; RSDNPK: synthetic N fertilizer plus crop residues. As compared to the standard NPK treatment, annual NO3 ? leaching losses for OMNPK and RSDNPK treatments were decreased by 36 and 22%, respectively (P < 0.05). Similarly, crop yield-scaled NO3 ? leaching for NPK treatment was higher than those for either OMNPK or RSDNPK treatments (P < 0.05). Direct N2O emissions for RSDNPK treatment were decreased as compared with NPK and OMNPK treatments (P < 0.05). Furthermore, the yield-scaled GWP (global warming potential) was lower for the treatments where either pig manure or crop residues were incorporated as compared to the standard NPK treatment (P < 0.05). Our study indicates that it is possible to reduce the negative environmental impact of NO3 ? leaching and N2O emissions without compromising crop productivity. Yield-scaled NO3 ? leaching, similar to the yield-scaled GWP, represents another valuable-integrated metric to address the dual goals of reducing nitrogen pollution and maintaining crop grain yield for a given agricultural system. 相似文献
960.
Philah Lee Subramanian Mohan Raj Shengfang Zhou Somasundar Ashok Selvakumar Edwardraja Sunghoon Park 《Biotechnology and Bioprocess Engineering》2014,19(1):1-7
This study examined the role and physiological relevance of 3-hydroxyisobutyrate dehydrogenase-I (3HIBDHI) of Pseudomonas denitrificans ATCC 13867 in the degradation of 3-hydroxypropionic acid (3-HP) during 3-HP production. The gene encoding 3HIBDH-I of P. denitrificans ATCC 13867 was cloned and expressed in Escherichia coli BL21 (DE3). The recombinant 3HIBDH-I was then purified on a Ni-NTA-HP column and characterized for its choice of substrates, cofactors, metals, reductants, and the optimal temperature and pH. The recombinant 3HIBDH-I showed a high catalytic constant (k cat/K m) of 604.1 ± 71.1 mM/S on (S)-3-hydroxyisobutyrate, but no detectable activity on (R)-3-hydroxyisobutyrate. 3HIBDH-I preferred NAD+ over NADP+ as a cofactor for its catalytic activity. The k cat/K m determined for 3-HP was 15.40 ± 1.43 mM/S in the presence of NAD+ at 37°C and pH 9.0. In addition to (S)-3-hydroxyisobutyrate and 3-HP, 3HIBDH-I utilized l-serine, methyl-d,l-serine, and methyl-(S)-(+)-3-hydroxy-2-methylpropionate; on the other hand, the k cat/K m values determined for these substrates were less than 5.0mM/S. Ethylenediaminetetraacetic acid, 2-mercaptoethanol, dithiothreitol and Mn2+ increased the activity of 3HIBDHI significantly, whereas the presence of Fe2+, Hg2+ and Ag+ in the reaction mixture at 1.0 mM completely inhibited its activity. This study revealed the characteristics of 3HIBDH-I and its significance in 3-HP degradation. 相似文献