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Plants have intricate mechanisms that tailor their defence responses to pathogens. WRKY transcription factors play a pivotal role in plant immunity by regulating various defence signalling pathways. Many WRKY genes are transcriptionally activated upon pathogen attack, but how their functions are regulated after transcription remains elusive. Here, we show that OsWRKY7 functions as a crucial positive regulator of rice basal immunity against Xanthomonas oryzae pv. oryzae (Xoo). The activity of OsWRKY7 was regulated at both translational and post-translational levels. Two translational products of OsWRKY7 were generated by alternative initiation. The full-length OsWRKY7 protein is normally degraded by the ubiquitin-proteasome system but was accumulated following elicitor or pathogen treatment, whereas the alternate product initiated from the downstream in-frame start codon was stable. Both the full and alternate OsWRKY7 proteins have transcriptional activities in yeast and rice cells, and overexpression of each form enhanced resistance to Xoo infection. Furthermore, disruption of the main AUG in rice increased the endogenous translation of the alternate stabilized form of OsWRKY7 and enhanced bacterial blight resistance. This study provides insights into the coordination of alternative translation and protein stability in the regulation of plant growth and basal defence mediated by the OsWRKY7 transcription factor, and also suggests a promising strategy to breed disease-resistant rice by translation initiation control.
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Oryza , Xanthomonas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Oryza/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Fitomejoramiento , Resistencia a la Enfermedad/genética , Inmunidad de la Planta/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Our ability to predict temperature responses of leaf respiration in light and darkness (RL and RDk ) is essential to models of global carbon dynamics. While many models rely on constant thermal sensitivity (characterized by Q10 ), uncertainty remains as to whether Q10 of RL and RDk are actually similar. We measured short-term temperature responses of RL and RDk in immature and mature leaves of two evergreen tree species, Castanopsis carlesii and Ormosia henry in an open field. RL was estimated by the Kok method, the Yin method and a newly developed Kok-iterCc method. When estimated by the Yin and Kok-iterCc methods, RL and RDk had similar Q10 (c. 2.5). The Kok method overestimated both Q10 and the light inhibition of respiration. RL /RDk was not affected by leaf temperature. Acclimation of respiration in summer was associated with a decline in basal respiration but not in Q10 in both species, which was related to changes in leaf nitrogen content between seasons. Q10 of RL and RDk in mature leaves were 40% higher than in immature leaves. Our results suggest similar Q10 values can be used to model RL and RDk while leaf development-associated changes in Q10 require special consideration in future respiration models.
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Fotosíntesis , Respiración , Temperatura , Oscuridad , Estaciones del Año , Hojas de la PlantaRESUMEN
Evaluating leaf day respiration rate (RL), which is believed to differ from that in the dark (RDk), is essential for predicting global carbon cycles under climate change. Several studies have suggested that atmospheric CO2 impacts RL. However, the magnitude of such an impact and associated mechanisms remain uncertain. To explore the CO2 effect on RL, wheat (Triticum aestivum) and sunflower (Helianthus annuus) plants were grown under ambient (410 ppm) and elevated (820 ppm) CO2 mole fraction ([CO2]). RL was estimated from combined gas exchange and chlorophyll fluorescence measurements using the Kok method, the Kok-Phi method, and a revised Kok method (Kok-Cc method). We found that elevated growth [CO2] led to an 8.4% reduction in RL and a 16.2% reduction in RDk in both species, in parallel to decreased leaf N and chlorophyll contents at elevated growth [CO2]. We also looked at short-term CO2 effects during gas exchange experiments. Increased RL or RL/RDk at elevated measurement [CO2] were found using the Kok and Kok-Phi methods, but not with the Kok-Cc method. This discrepancy was attributed to the unaccounted changes in Cc in the former methods. We found that the Kok and Kok-Phi methods underestimate RL and overestimate the inhibition of respiration under low irradiance conditions of the Kok curve, and the inhibition of RL was only 6%, representing 26% of the apparent Kok effect. We found no significant long-term CO2 effect on RL/RDk, originating from a concurrent reduction in RL and RDk at elevated growth [CO2], and likely mediated by acclimation of nitrogen metabolism.
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Dióxido de Carbono , Fotosíntesis , Fotosíntesis/fisiología , Dióxido de Carbono/metabolismo , Hojas de la Planta/metabolismo , Clorofila/metabolismo , RespiraciónRESUMEN
The response of mesophyll conductance (gm) to CO2 plays a key role in photosynthesis and ecosystem carbon cycles under climate change. Despite numerous studies, there is still debate about how gm responds to short-term CO2 variations. Here we used multiple methods and looked at the relationship between stomatal conductance to CO2 (gsc) and gm to address this aspect. We measured chlorophyll fluorescence parameters and online carbon isotope discrimination (Δ) at different CO2 mole fractions in sunflower (Helianthus annuus L.), cowpea (Vigna unguiculata L.), and wheat (Triticum aestivum L.) leaves. The variable J and Δ based methods showed that gm decreased with an increase in CO2 mole fraction, and so did stomatal conductance. There were linear relationships between gm and gsc across CO2 mole fractions. gm obtained from A-Ci curve fitting method was higher than that from the variable J method and was not representative of gm under the growth CO2 concentration. gm could be estimated by empirical models analogous to the Ball-Berry model and the USO model for stomatal conductance. Our results suggest that gm and gsc respond in a coordinated manner to short-term variations in CO2, providing new insight into the role of gm in photosynthesis modelling.
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Dióxido de Carbono , Helianthus , Células del Mesófilo , Estomas de Plantas , Triticum , Dióxido de Carbono/metabolismo , Estomas de Plantas/fisiología , Células del Mesófilo/fisiología , Células del Mesófilo/metabolismo , Triticum/fisiología , Triticum/metabolismo , Helianthus/fisiología , Helianthus/metabolismo , Isótopos de Carbono , Fotosíntesis/fisiología , Fabaceae/fisiología , Clorofila/metabolismo , Hojas de la Planta/fisiología , Hojas de la Planta/metabolismoRESUMEN
Hyperuricemia closely correlates with the development of atherosclerosis, but little is known of the mechanism by which atherosclerosis progression occurs in hyperuricemia. Atherosclerosis appears to involve pyroptosis, an emerging mechanism of proinflammatory regulated cell death. This study tested the hypothesis that pyroptosis underlies the relationship between hyperuricemia and atherosclerosis, using ApoE-/- mice (a model of atherosclerosis), human umbilical vein endothelial cells (HUVECs), and human atherosclerotic arterial samples. We found that hyperuricemia can aggravate the aortic atherosclerotic plaque-load in ApoE-/- mice and promote endothelial cell pyroptosis. Additionally, hyperuricemia can increase the levels of serum inflammatory factors (including IL-1ß and IL-18). Exposure to lipopolysaccharide plus a high concentration of soluble uric acid (≥12 mg/dL) induced cell pyroptosis in HUVECs, as evidenced by increased expression of pyroptosis-related proteins and elevated release of lactate dehydrogenase (a marker of tissue damage). Further, MCC950, a selective nucleotide-binding oligomerization domain (NOD)-like receptor 3 (NLRP3) inflammasome inhibitor, and N-acetyl- l-cysteine, an antioxidant, attenuated HUVEC pyroptosis by inhibiting activation of the NLRP3 inflammasome and production of intracellular reactive oxygen species (ROS). Finally, we detected significantly higher expression of pyroptosis-associated proteins in carotid specimens from patients with hyperuricemia. Collectively, our findings suggest that hyperuricemia can aggravate endothelial cell pyroptosis in aortic atherosclerotic plaques, promoting the development of atherosclerosis. Additionally, a high concentration of soluble uric acid can trigger the activation stage of the NLRP3 inflammasome, mediating endothelial cell pyroptosis, and this process is regulated by the cellular ROS level.
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Aterosclerosis , Hiperuricemia , Humanos , Ratones , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Piroptosis , Ácido Úrico/metabolismo , Hiperuricemia/complicaciones , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Aterosclerosis/metabolismo , Apolipoproteínas E/metabolismoRESUMEN
The basal levels of salicylic acid (SA) vary dramatically among plant species. In the shoot, for example, rice contains almost 100 times higher SA levels than Arabidopsis. Despite its high basal levels, neither the biosynthetic pathway nor the biological functions of SA are well understood in rice. Combining with metabolite analysis, physiological, and genetic approaches, we found that the synthesis of basal SA in rice shoot is dependent on OsAIM1, which encodes a beta-oxidation enzyme in the phenylalanine ammonia-lyase (PAL) pathway. Compromised SA accumulation in the Osaim1 mutant led to a lower shoot temperature than wild-type plants. However, this shoot temperature defect resulted from increased transpiration due to elevated steady-state stomatal aperture in the mutant. Furthermore, the high basal SA level is required for sustained expression of OsWRKY45 to modulate the steady-state stomatal aperture and shoot temperature in rice. Taken together, these results provide the direct genetic evidence for the critical role of the PAL pathway in the biosynthesis of high basal level SA in rice, which plays an important role in the regulation of steady-state stomatal aperture to promote fitness under stress conditions.
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Proteínas de Arabidopsis , Arabidopsis , Oryza , Oryza/metabolismo , Ácido Salicílico/metabolismo , Plantas/metabolismo , Arabidopsis/genética , Fenilanina Amoníaco-Liasa/genética , Fenilanina Amoníaco-Liasa/metabolismo , Regulación de la Expresión Génica de las Plantas , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Proteínas de Arabidopsis/metabolismoRESUMEN
Background: Postoperative new atrial fibrillation (POAF) is a commonly observed complication after off-pump coronary artery bypass surgery (OPCABG), and models based on radiomics features of epicardial adipose tissue (EAT) on non-enhanced computer tomography (CT) to predict the occurrence of POAF after OPCABG remains unclear. This study aims to establish and validate models based on radiomics signature to predict POAF after OPCABG. Methods: Clinical characteristics, radiomics signature and features of non-enhanced CT images of 96 patients who underwent OPCABG were collected. The participants were divided into a training and a validation cohort randomly, with a ratio of 7:3. Clinical characteristics and EAT CT features with statistical significance in the multivariate logistic regression analysis were utilized to build the clinical model. The least absolute shrinkage and selection operator (LASSO) algorithm was used to identify significant radiomics features to establish the radiomics model. The combined model was constructed by integrating the clinical and radiomics models. Results: The area under the curve (AUC) of the clinical model in the training and validation cohorts were 0.761 (95% CI: 0.634-0.888) and 0.797 (95% CI: 0.587-1.000), respectively. The radiomics model showed better discrimination ability than the clinical model, with AUC of 0.884 (95% CI: 0.806-0.961) and 0.891 (95% CI: 0.772-1.000) respectively for the training and the validation cohort. The combined model performed best and exhibited the best predictive ability among the three models, with AUC of 0.922 (95% CI: 0.853-0.990) in the training cohort and 0.913 (95% CI: 0.798-1.000) in the validation cohort. The calibration curve demonstrated strong concordance between the predicted and actual observations in both cohorts. Furthermore, the Hosmer-Lemeshow test yielded p value of 0.241 and 0.277 for the training and validation cohorts, respectively, indicating satisfactory calibration. Conclusions: The superior performance of the combined model suggests that integrating of clinical characteristics, radiomics signature and features on non-enhanced CT images of EAT may enhance the accuracy of predicting POAF after OPCABG.
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BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and morbidity, and imposes a substantial financial burden on society. However, few studies have examined the role of individual socioeconomic status (SES) in temporal trends of COPD prevalence and economic cost. This study aimed to uncover the changing prevalence and economic burden of COPD across socioeconomic gradients in rural southwest China. METHODS: Data were collected from two cross-sectional health interviews and examination surveys administered 10 years apart among individuals aged ≥ 35 years in rural China. A prevalence-based cost-of-illness method was used to estimate the cost of COPD. The individual socioeconomic position (SEP) index was constructed using principal component analysis. Post-bronchodilator spirometry tests were performed for each participant. RESULTS: From 2011 to 2021, the prevalence of COPD increased from 8.7% to 12.8% (P < 0.01), while the economic cost of COPD increased 1.9-fold. Unit hospital costs and outpatient costs increased 1.57-fold and 1.47-fold, while unit medication costs fell by 10.6%. Increasing prevalence was also observed when the data were stratified by sex, age, ethnicity, level of education, level of income, and SEP (P < 0.05). Men, ethnic minorities, and those with a lower educational level, lower income, or lower SEP had a higher prevalence of COPD than their counterparts both in 2011 and 2021 (P < 0.05). Unit outpatient costs and medication costs increased with patients' SEP in both survey years (P < 0.05). CONCLUSIONS: The prevalence and economic costs of COPD increased substantially across all socioeconomic gradients in rural southwest China in the decade from 2011 and 2021. Future COPD prevention and management interventions as well as efforts to improve access to affordable COPD medication and treatment should focus in particular on ethnic minority and low SEP populations.
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Estrés Financiero , Enfermedad Pulmonar Obstructiva Crónica , Masculino , Humanos , Factores Socioeconómicos , Etnicidad , Prevalencia , Estudios Transversales , Grupos Minoritarios , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , China/epidemiologíaRESUMEN
INTRODUCTION: Osteoarthritis (OA) is a degenerative disease common in the elderly and is characterized by joint pain, swelling, and restricted movement. In recent years, heparanase has been reported to play an important role in the development of osteoarthritic cartilage. PG545 is a heparan sulfate mimetic with heparanase inhibitory activity. In this study, the therapeutic effects and possible mechanisms of PG545 were investigated in a chondrocyte injury model induced by interleukin-1ß (IL -1ß). METHODS: Following treatment with PG545 or the autophagy inhibitor 3-methyladenine (3-MA), chondrocyte viability was detected using Cell Counting Kit-8 and fluorescein diacetate/propidium iodide double staining. The apoptosis rate of chondrocytes was determined by flow cytometry. Expression of light chain 3 and P62 was monitored by immunofluorescence labeling. Western blot, lentivirus infection with red fluorescent protein and green fluorescent protein, and quantitative real-time polymerase chain reaction were used to determine the expression levels of chondrocyte markers, apoptosis-related factors, autophagy proteins, and key proteins of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway. The expression and activity of stress-specific enzymes such as malondialdehyde, superoxide dismutase, and catalase (CAT) were investigated. Chondrocytes with ATG5 knockdown were used to investigate the relationship between the therapeutic effect of PG545 and autophagy. The therapeutic effect of PG545 was verified in vivo. RESULTS: PG545 had a significant protective effect on chondrocytes by reducing oxidative stress, apoptosis, and degradation of chondrocytes and increasing chondrocyte proliferation. PG545 was effective in inducing autophagy in IL-1ß-treated cells, while 3-MA attenuated the effect. The PI3K/Akt/mTOR pathway may be involved in the promotion of autophagy and OA treatment by PG545. CONCLUSION: PG545 was able to restore impaired autophagy and autophagic flux via the PI3K/Akt/mTOR pathway, thereby delaying the progression of OA, suggesting that PG545 may be a novel therapeutic approach for OA.
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Osteoartritis , Proteínas Proto-Oncogénicas c-akt , Humanos , Anciano , Proteínas Proto-Oncogénicas c-akt/metabolismo , Condrocitos , Fosfatidilinositol 3-Quinasas/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/prevención & control , Osteoartritis/metabolismo , Fosfatidilinositol 3-Quinasa , Inhibidores de la Angiogénesis/farmacología , Autofagia , ApoptosisRESUMEN
Animal manure is an important raw material for Agaricus bisporus production; however, it is also a reservoir for antibiotic residues, antibiotic resistance genes (ARGs), and antibiotic-resistant bacteria. Little is known about the influence of the commercial cultivation of A. bisporus on the dynamics of ARGs and the underlying mechanisms that cause their variations. In this study, we investigated the fate of 285 ARGs, 10 mobile genetic elements, and seven major categories of antibiotic residues in substrate and mushroom samples at different production phases. The results showed that commercial substrate preparation, particularly the pasteurization phase, was highly efficient in removing ARGs from the substrate. We further found that mycelium proliferation of A. bisporus contributed significantly to the removal of ARGs from the substrate and casing soil. The bacterial community is the key driver of changes in ARGs during the commercial cultivation of A. bisporus, which explained 46.67% of the variation in ARGs. Our results indicate that, despite the addition of animal manure, the risk of ARG dissemination to fruiting bodies and the environment is low. We propose that bioremediation by specific edible fungi might be a novel and promising method for scavenging antimicrobial resistance contamination from soil environment.
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Antibacterianos , Compostaje , Animales , Estiércol/microbiología , Bacterias/genética , Suelo/química , Farmacorresistencia Microbiana/genética , Genes BacterianosRESUMEN
Urbanization-induced phenological changes have received considerable attention owing to their implications for determining urban ecosystem productivity and predicting the response of plants and ecosystem carbon cycles to future climate change. However, inconsistent rural-urban gradients in plant phenology remain, and phenological drivers other than temperature are poorly understood. In this study, we simultaneously observed the micro-climate and spring leaf phenology of seven woody plant species at 13 parks along a rural-urban gradient in Beijing, China. The minimum (Tmin) and mean (Tmean) air temperature and the minimum (VPDmin) and mean (VPDmean) vapor pressure deficit increased significantly along the rural-urban gradient, but the maximum air temperature (Tmax) and maximum vapor pressure deficit (VPDmax) did not. All observed leaf phenological phases for the seven species were significantly advanced along the rural-urban gradient by 0.20 to 1.02 days/km. Advances in the occurrence of leaf phenological events were significantly correlated with increases in Tmean (accounting for 57-59% variation), Tmin (21-26%), VPDmin (12-16%), and VPDmean (3-5%), but not with changes in Tmax or VPDmax. Advances in spring leaf phenology along the rural-urban gradient differed between non-native species and native species and between shrubs and trees. The reason may be mainly that the sensitivities of spring leaf phenology to micro-climate differ with species origin and growth form. This study highlights that urbanization-induced increases in Tmean and Tmin are the major contributors to advances in spring leaf phenology along the rural-urban gradient, exerting less influence on native species than on non-native species.
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Ecosistema , Árboles , Beijing , Temperatura , Estaciones del Año , Plantas , Hojas de la Planta , Cambio ClimáticoRESUMEN
Ferredoxin 1 (FD1) accepts and distributes electrons in the electron transfer chain of plants. Its expression is universally downregulated by viruses and its roles in plant immunity have been brought into focus over the past decade. However, the mechanism by which viruses regulate FD1 remains to be defined. In a previous report, we found that the expression of Nicotiana benthamiana FD1 (NbFD1) was downregulated following infection with potato virus X (PVX) and that NbFD1 regulates callose deposition at plasmodesmata to play a role in defense against PVX infection. We now report that NbFD1 is downregulated by rice stripe virus (RSV) infection and that silencing of NbFD1 also facilitates RSV infection, while viral infection was inhibited in a transgenic line overexpressing NbFD1, indicating that NbFD1 also functions in defense against RSV infection. Next, a RSV-derived small interfering RNA was identified that contributes to the downregulation of FD1 transcripts. Further analysis showed that the abscisic acid (ABA) which accumulates in RSV-infected plants also represses NbFD1 transcription. It does this by stimulating expression of ABA insensitive 5 (ABI5), which binds the ABA response element motifs in the NbFD1 promoter, resulting in negative regulation. Regulation of FD1 by ABA was also confirmed in RSV-infected plants of the natural host rice. The results therefore suggest a mechanism by which virus regulates chloroplast-related genes to suppress their defense roles.
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Ferredoxinas/genética , Nicotiana/virología , Oryza/virología , Proteínas de Plantas/genética , Tenuivirus/patogenicidad , Ácido Abscísico , Arabidopsis/genética , Resistencia a la Enfermedad/genética , Regulación hacia Abajo , Ferredoxinas/metabolismo , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Patógeno/fisiología , Oryza/genética , Oryza/metabolismo , Enfermedades de las Plantas/virología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , ARN Interferente Pequeño , Tenuivirus/genética , Nicotiana/genética , Nicotiana/metabolismoRESUMEN
Floral transition, the change from vegetative growth to reproductive development, is dramatic in flowering plants. Here, we show that one subgroup III member of the B-box (BBX) family, BBX17, is a repressor of floral transition under long-day conditions. BBX17 contains a B-box domain and a CCT domain. Although the phenotype of the BBX17 loss-of-function plants was comparable to that of wild-type plants, BBX17-overexpression plants displayed a delayed-flowering phenotype under long-day conditions. The delayed-flowering phenotype was not the result of an altered CONSTANS (CO) expression level but rather the repression of the FLOWERING LOCUS T (FT) expression level. BBX17 physically associated with CO and repressed its ability to control FT expression. Furthermore, the BBX17 protein degraded in the dark, but irradiating seedlings with white, blue, red or far-red light stabilized the BBX17 level. We also proved that the degradation of BBX17 was via 26S proteasome and requires COP1. Thus, BBX17 acts as a key factor in the CO-FT regulatory system to control Arabidopsis thaliana flowering.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Flores/fisiología , Regulación de la Expresión Génica de las Plantas , Fotoperiodo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Many TGA transcription factors participate in immune responses in the SA-mediated signaling pathway in Arabidopsis. This study identified a transcription factor OsTGAL1, which is induced upon infection by Xoo. Overexpression of OsTGAL1 increased the susceptibility of rice to Xoo. Plants overexpressing OsTGAL1 could affect the expression of many SA signaling-related genes. OsTGAL1 was able to interact with the promoter of OsSGT1, which encodes a key enzyme for SA metabolism. The transcript of OsSGT1 was induced by Xoo and this responsive expression was further increased in plants overexpressing OsTGAL1. OsSGT1 knockout lines had enhanced resistance to Xoo, and knocking out OsSGT1 in plants overexpressing OsTGAL1 blocked the susceptibility caused by OsTGAL1. Altered expression levels of several OsPRs in all the transgenic plants demonstrated that SA-mediated signaling had been affected. Furthermore, we identified an oxidoreductase of CC-type glutaredoxin, OsGRX17, which interacted with OsTGAL1. OsGRX17 reduced the regulation of OsTGAL1 on OsSGT1, and this may be due to its redox modulation. Thus, our results demonstrate that OsTGAL1 negatively regulates resistance to Xoo by its effects on SA metabolism via the activation of OsSGT1, which provides valuable targets for plant breeders in developing new cultivars that are resistant to Xoo.
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Arabidopsis , Oryza , Xanthomonas , Arabidopsis/genética , Arabidopsis/metabolismo , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/metabolismo , Oryza/metabolismo , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Ácido Salicílico/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
The striped-back shrew group demonstrates remarkable variation in skull and body size, tail length, and brightness of the dorsal stripe; and karyotypic and DNA variation has been reported in recent years. In this study, we investigated the phylogenetic structure of the group, as well as speciation patterns and demographic history in Mountains of Southwestern China and adjacent mountains, including the southern Himalayas, Mts. Bashan, Wushan, and Qinling. We sequenced a total of 462 specimens from 126 localities in the known range of the group, which were sequenced and analyzed based on 6.2 kb of sequence data from two mitochondrial, six nuclear, and two Y chromosome markers. Phylogenetic analyses of the concatenated mtDNA data revealed 14 sympatric and independently evolving lineages within the striped-back shrew group, including Sorex bedfordiae, S. cylindricauda, S. excelsus, S. sinalis and several cryptic species. All concatenated data (ten genes) showed a consistent genetic structure compared to the mtDNA lineages for the group, whereas the nuclear and the Y chromosome data showed a discordant genetic structure compared to the mtDNA lineages for the striped-back shrew group. Species delimitation analyses and deep genetic distance clearly support the species status of the 14 evolving lineages. The divergence time estimation suggested that the striped-back shrew group began to diversify from the middle Pleistocene (2.34 Ma), then flourished at approximately 2.14 Ma, followed by a series of rapid diversifications through the Pleistocene. Our results also revealed multiple mechanisms of speciation in the Mountains of Southwestern China and Adjacent Mountains with complex landscapes and climate. The uplifting of the Qinghai-Tibetan Plateau, Quaternary climate oscillations, riverine barriers, ecological elevation gradients, topographical diversity, and their own low dispersal capacity may have driven the speciation, genetic structure, and phylogeographic patterns of the striped-back shrew group.
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Eulipotyphla , Musarañas , Animales , ADN Mitocondrial/genética , Marcadores Genéticos , Variación Genética , Filogenia , Musarañas/genéticaRESUMEN
A delay line-type surface acoustic wave (SAW) gas sensor based on p-hexafluoroisopropanol phenyl (HFIPPH) functionalized multi-walled carbon nanotube (MWCNT) film is developed to detect organophosphorus dimethyl methylphosphonate (DMMP) vapor (a simulant of chemical nerve agent sarin). Inspired by the transfer process of Cu-based graphene, a uniform and size-controllable HFIPPH-MWCNT film is successfully prepared on the SAW device via a wet-etching transfer method. For the first time, we use the method of measuring the change of the sensor's insertion loss to achieve the detection of ultra-low concentration DMMP vapor. The designed sensor exhibits a fast response/recovery time about 3 s/50 s, and a low detection limit of 0.1 ppm. Additionally, the stability and selectivity of the sensor and the influence of humidity on its response are evaluated through experiments. The acoustoelectric effect is proved to be the sensing mechanism of the sensor insertion loss response.
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Chronic periodontitis (CP) is a kind of multifactorial common oral diseases. Multiple immune molecules including interleukin-2 (IL-2) are involved in the occurrence and development of CP. To investigate the association between the IL2 rs2069762 polymorphism and the risk of CP in Chinese individuals, we recruited 375 CP patients and 443 controls in this case-control study. The PCR-RFLP method was used for genotyping. Data revealed that the GG genotype was related with a decreased risk of CP (GG vs TT: OR, 0.58, 95%CI, 0.37-0.92, P-value = 0.020; GG vs TG+TT: OR, 0.61, 95%CI, 0.39-0.94, P-value = 0.027). Besides, G allele was shown to decrease the risk of CP. In addition, the IL2 rs2069762 polymorphism was related with the severity of CP. To sum up, the IL2 rs2069762 polymorphism is related with a decreased risk and severity of CP in Chinese individuals.
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Periodontitis Crónica , Interleucina-2 , Estudios de Casos y Controles , China , Periodontitis Crónica/genética , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Interleucina-2/genética , Polimorfismo de Nucleótido SimpleRESUMEN
The interactions between azole-anion-based ionic liquids (AILs) and 2-methyl-3-butyn-2-ol (MBY) play an important role in AIL-promoted carboxylative cyclization of MBY with CO2. To better understand the interactions between AILs ([P66614][Im], [P66614][4-MeIm], and [P66614][4-BrIm]) and MBY, a detailed investigation from the experimental perspective has been carried out in this study. The results show that the derivative of viscosity (η) with the mole fraction of AIL (xAIL) of AIL + MBY mixtures appears to have the maximum value when xAIL ≈ 0.3, while 1H NMR chemical shifts of P-CH2 of [P66614]+ reach the minimum value at xAIL ≈ 0.3, indicating that [P66614]+ of AILs tend to self-aggregate. The interaction parameters (gji-gii) of the systems obtained from η by the Eyring-UNIQUAC equation are positive, and the difference between the bulk and local composition (xi-xii) is always negative, indicating that AILs can interact with MBY. Moreover, excess molar volumes and isentropic compressibility deviations are all negative deviations and become more negative as the temperature increases, reaching a minimum value at xAIL ≈ 0.30, indicating that azole-based anions can form H-bonds with MBY, and MBY molecules tend to enter the aggregates formed by AILs. Consequently, the cage effect is proposed to describe the interactions between AILs and MBY: MBY first enters the cage formed by the aggregation of [P66614]+, and then forms H-bonds with azole-based anions. Finally, the sizes of the particles of the [P66614][Im] + MBY mixture from dynamic light scattering increase first and then decrease with xAIL, with the maximum of 122 nm at xAIL ≈ 0.25, which confirms the rationality of the cage effect.
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BACKGROUND We aimed to evaluate the association between postoperative nadir hematocrit (Hct) and severe acute kidney injury (AKI) in patients undergoing off-pump coronary artery bypass graft (OPCABG) surgery. MATERIAL AND METHODS Data of patients who received OPCABG were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. A generalized additive model was applied to explore the relationship between nadir Hct and severe AKI. Patients were divided into 4 groups by quartiles of postoperative nadir Hct, with the lowest group (Hct <25%) as reference. We conducted multivariate logistic regression models to calculate adjusted odds ratios (OR) and 95% CI and evaluate trend among the 4 groups. RESULTS In total, 1783 OPCABG patients were included. A nonlinear association between nadir Hct and severe AKI was identified. After adjusting for potential confounders, nadir Hct was negatively associated with risk of severe AKI when Hct was less than 31%; there was no statistical significance between highest Hct group (Hct ≥31%) and control group (Hct <25%; P>0.05). Tests for trend were significant (P<0.05). Subgroup analyses showed each 1% increase in postoperative nadir Hct was associated with a 23% decrease in risk of severe AKI (OR, 0.77; P=0.002) in lower BMI group (<30 kg/m²). CONCLUSIONS The association between postoperative nadir Hct and severe AKI in patients after OPCABG was nonlinear. Lower nadir Hct may be associated with increased risk of severe AKI when Hct values are less than 31%. However, no statistical significance was found between the highest Hct group and control group.
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Lesión Renal Aguda , Puente de Arteria Coronaria Off-Pump , Humanos , Puente de Arteria Coronaria Off-Pump/efectos adversos , Hematócrito , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Lesión Renal Aguda/etiología , Cuidados Críticos , Factores de RiesgoRESUMEN
Airborne fungi can pose serious health concerns in humans; however, the area-specific abundance and composition of airborne fungal microbiota discharged from composting facilities remain unclear. In the present study, we collected air samples from composting, packaging, office, and downwind areas of four commercial composting facilities. The characteristics of airborne fungi, including pathogen/allergen-containing genera, and their corresponding human exposure in different areas of composting facilities were analyzed using high-throughput sequencing and ddPCR. High fungal concentrations and richness were detected in the air of the packaging area. In all four areas, Ascomycota, Basidiomycota, and Mucoromycota were observed to be the primary fungal phyla, with Cladosporium, Alternaria, and Aspergillus as the consistently dominant fungal genera. A large number of endemic airborne fungi were found in the composting and packaging areas, which also shared the most common airborne fungi as well as pathogen/allergen-containing genera. The packaging area contributed substantially to airborne fungi in the office and downwind areas. Area-specific human exposure to broad airborne fungal compositions was revealed, especially regarding the pathogen/allergen-containing genera. Current results provide valuable data for a comprehensive understanding of area-specific airborne fungi in composting facilities and highlight the importance of assessing the inhaled exposure to airborne fungi in evaluating their following health risks.