RESUMO
OBJECTIVE: ASPP1 (apoptosis stimulating of p53 protein 1) is critical in regulating cell apoptosis as a cofactor of p53 to promote its transcriptional activity in the nucleus. However, whether cytoplasmic ASPP1 affects p53 nuclear trafficking and its role in cardiac diseases remains unknown. This study aims to explore the mechanism by which ASPP1 modulates p53 nuclear trafficking and the subsequent contribution to cardiac ischemia/reperfusion (I/R) injury. METHODS AND RESULTS: The immunofluorescent staining showed that under normal condition ASPP1 and p53 colocalized in the cytoplasm of neonatal mouse ventricular cardiomyocytes, while they were both upregulated and translocated to the nuclei upon hypoxia/reoxygenation treatment. The nuclear translocation of ASPP1 and p53 was interdependent, as knockdown of either ASPP1 or p53 attenuated nuclear translocation of the other one. Inhibition of importin-ß1 resulted in the cytoplasmic sequestration of both p53 and ASPP1 in neonatal mouse ventricular cardiomyocytes with hypoxia/reoxygenation stimulation. Overexpression of ASPP1 potentiated, whereas knockdown of ASPP1 inhibited the expression of Bax (Bcl2-associated X), PUMA (p53 upregulated modulator of apoptosis), and Noxa, direct apoptosis-associated targets of p53. ASPP1 was also increased in the I/R myocardium. Cardiomyocyte-specific transgenic overexpression of ASPP1 aggravated I/R injury as indicated by increased infarct size and impaired cardiac function. Conversely, knockout of ASPP1 mitigated cardiac I/R injury. The same qualitative data were observed in neonatal mouse ventricular cardiomyocytes exposed to hypoxia/reoxygenation injury. Furthermore, inhibition of p53 significantly blunted the proapoptotic activity and detrimental effects of ASPP1 both in vitro and in vivo. CONCLUSIONS: Binding of ASPP1 to p53 triggers their nuclear cotranslocation via importin-ß1 that eventually exacerbates cardiac I/R injury. The findings imply that interfering the expression of ASPP1 or the interaction between ASPP1 and p53 to block their nuclear trafficking represents an important therapeutic strategy for cardiac I/R injury.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Traumatismo por Reperfusão , Proteína Supressora de Tumor p53 , Animais , Camundongos , Apoptose/fisiologia , Hipóxia/metabolismo , Isquemia/metabolismo , Carioferinas , Miócitos Cardíacos/metabolismo , Traumatismo por Reperfusão/metabolismo , Proteína Supressora de Tumor p53/genética , Proteínas Adaptadoras de Transdução de Sinal/genéticaRESUMO
This study aimed to explore the effects of peroxisome proliferator-activated receptor γ (PPARγ) inhibition on fracture healing of nonunion and the underlying mechanisms. Bone marrow mesenchymal stem cells (BMSCs) were treated with PPARγ antagonist GW9662 (5 µM, 10 µM). Alkaline phosphatase (ALP) staining and Alizarin Red S was used to assess early stage of osteogenesis and osteogenic differentiation. GW9662 (1 mg/kg/day) were administered intraperitoneally into the rats with bone fracture. Bone healing processes in the rat femur fracture model were recorded and assessed by radiographic methods on Weeks 8, 14, and 20 postoperation. Osteogenesis and angiogenesis at the fracture sites were evaluated by radiographic and histological methods on postoperative Week 20. GW9662 treatment increased ALP activity and Alp mRNA expression in rat BMSCs. Moreover, GW9662 administration increased matrix mineralization and mRNA and protein levels of Bmp2 and Runx2 in the BMSCs. In addition, GW9662 treatment improved radiographic score in the fracture rats and increased osteogenesis-related proteins, including type I collagen, osteopontin, and osteoglycin, in the bone tissues of the fracture sites. In conclusion, PPARγ inhibition promotes osteogenic differentiation of rat BMSCs, as well as improves the fracture healing of rats through Bmp2/Runx2 signaling pathway in the rat model of bone fracture.
Assuntos
Anilidas , Diferenciação Celular , Consolidação da Fratura , Células-Tronco Mesenquimais , Osteogênese , PPAR gama , Animais , Masculino , Ratos , Anilidas/farmacologia , Proteína Morfogenética Óssea 2 , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Consolidação da Fratura/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , PPAR gama/antagonistas & inibidores , PPAR gama/metabolismo , Ratos Sprague-DawleyRESUMO
Examining the connection between P and starch-related signals can help elucidate the balance between nutrients and yield. This study utilized 307 diverse maize inbred lines to conduct multi-year and multi-plot trials, aiming to explore the relationship among P content, starch content, and 100-kernel weight (HKW) of mature grains. A significant negative correlation was found between P content and both starch content and HKW, while starch content showed a positive correlation with HKW. The starch granules in grains with high-P and low-starch content (HPLS) were significantly smaller compared to grains with low-P high-starch content (LPHS). Additionally, mian04185-4 (HPLS) exhibited irregular and loosely packed starch granules. A significant decrease in ZmPHOs genes expression was detected in the HPLS line ZNC442 as compared to the LPHS line SCML0849, while no expression difference was observed in AGPase encoding genes between these two lines. The down-regulated genes in ZNC442 grains were enriched in nucleotide sugar and fatty acid anabolic pathways, while up-regulated genes were enriched in the ABC transporters pathway. An accelerated breakdown of fat as the P content increased was also observed. This implied that HPLS was resulted from elevated lipid decomposition and inadequate carbon sources. The GWAS analysis identified 514 significantly associated genes, out of which 248 were differentially expressed. Zm00001d052392 was found to be significantly associated with P content/HKW, exhibiting high expression in SCML0849 but almost no expression in ZNC442. Overall, these findings suggested new approaches for achieving a P-yield balance through the manipulation of lipid metabolic pathways in grains.
Assuntos
Fósforo , Amido , Transcriptoma , Zea mays , Zea mays/genética , Zea mays/metabolismo , Amido/metabolismo , Fósforo/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , FenótipoRESUMO
Phosphorus (P) is an essential element for plant growth, and its deficiency can cause decreased crop yield. This study systematically evaluated the low-phosphate (Pi) response traits in a large population at maturity and seedling stages, and explored candidate genes and their interrelationships with specific traits. The results revealed a greater sensitivity of seedling maize to low-Pi stress compared to that at maturity stage. The phenotypic response patterns to low-Pi stress at different stages were independent. Chlorophyll content was found to be a potential indicator for screening low-Pi-tolerant materials in the field. A total of 2900 and 1446 significantly associated genes at the maturity and seedling stages were identified, respectively. Among these genes, 972 were uniquely associated with maturity traits, while 330 were specifically detected at the seedling stage under low-Pi stress. Moreover, 768 and 733 genes were specifically associated with index values (low-Pi trait/normal-Pi trait) at maturity and seedling stage, respectively. Genetic network diagrams showed that the low-Pi response gene Zm00001d022226 was specifically associated with multiple primary P-related traits under low-Pi conditions. A total of 963 out of 2966 genes specifically associated with traits under low-Pi conditions or index values were found to be induced by low-Pi stress. Notably, ZmSPX4.1 and ZmSPX2 were sharply up-regulated in response to low-Pi stress across different lines or tissues. These findings advance our understanding of maize's response to low-Pi stress at different developmental stages, shedding light on the genes and pathways implicated in this response.
Assuntos
Fenótipo , Fósforo , Plântula , Estresse Fisiológico , Zea mays , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento , Estresse Fisiológico/genética , Fósforo/metabolismo , Genes de Plantas , Estudo de Associação Genômica Ampla , Clorofila/metabolismo , Locos de Características Quantitativas , Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Pulsed light detecting and ranging (Lidar) is capable of acquiring comprehensive target information within a single pulse, including distance and intensity data. Intensity data reflects the target's backscattered intensity and is commonly regarded as a crucial observational parameter associated with target reflectivity information. Multiple studies have indicated the potential of intensity data in various applications within pulsed Lidar contexts. However, the intensity data is influenced by the incident angle and distance; hence it cannot directly manifest target characteristics. Consequently, a prerequisite for its usage is the implementation of intensity calibration. This paper presents a target intensity correction method based on an improved tail model, designed for preprocessing intensity data. First, the pulse echo signal equation is derived by incorporating the improved tail model with the detected target. On this foundation, a target echo intensity correction model is established to correct the intensities at various incident angles to those at the normal direction. Lastly, the derived approach is validated through simulation analysis, and practical experiments are conducted on a constructed pulsed Lidar system. These experiments meticulously investigate the influences of incident angle and distance, two prominent factors, on echo intensity. In the context of incident angle correction experiments, the mean absolute errors (MAEs) in calibrated values for diverse targets all remain within 0.04 V. Prior to correction, the maximum MAE for the cystosepiment is 0.505 V; after the correction it is reduced to merely 0.02 V, indicating a 96% reduction in error. Furthermore, all discrepancies exhibit an error standard deviation (ESD) of 0.03 V or less, showcasing favorable stability. For distance correction, under normal incidence conditions, a diverse set of targets is measured at different distances to achieve corrected MAE and ESD within 0.05 V. Consequently, the proposed method effectively achieves intensity correction concerning incident angles and distances. To achieve this, a reflectivity lookup table for the relevant targets was established. Combining this with the corrected intensity information enabled target identification in the three-dimensional imaging of pulsed Lidar.
RESUMO
Osteoarthritis (OA) is a prevalent degenerative joint disease with a lack of effective therapeutic. Chondrocyte ferroptosis contributes to the progression of OA. PUM2 is shown to exacerbate ischemia-reperfusion-induced neuroinflammation by promoting ferroptosis, but its role in OA remains unexplored. Here, primary mouse chondrocytes were stimulated with IL-1ß to mimic OA chondrocyte injury in vitro. And PUM2 was upregulated in OA cartilage tissues and IL-1ß-induced chondrocytes. Silencing PUM2 alleviated IL-1ß-induced chondrocyte inflammation and ECM degradation. Mechanistically, PUM2 facilitated the degradation of NEDD4 mRNA by binding to the 3'UTR of NEDD4 mRNA, which in turn inhibited NEDD4 induced PTEN ubiquitination and degradation. Consistently, NEDD4 silencing reversed the ameliorative effect of PUM2 knockdown on chondrocyte injury, and overexpression of PTEN abolished the improved role of NEDD4 in chondrocyte injury. Moreover, PTEN aggravated IL-1ß-induced ferroptosis in chondrocytes through the Nrf2/HO-1 pathway by increasing the levels of Fe2+, ROS, MDA, and ACSL4 protein, decreasing the activity of SOD and the levels of GSH and GPX4 protein, and aggravating mitochondrial damage. Additionally, destabilized medial meniscus (DMM) were conducted to establish the OA mouse model, and adenovirus-mediated PUM2 shRNA was administered intra-articularly. Silencing PUM2 attenuated OA-induced cartilage damage in vivo. In conclusion, PUM2 promoted OA progression through PTEN-mediated chondrocyte ferroptosis by facilitating NEDD4 mRNA degradation.
Assuntos
Condrócitos , Ferroptose , Ubiquitina-Proteína Ligases Nedd4 , Osteoartrite , PTEN Fosfo-Hidrolase , Animais , Humanos , Masculino , Camundongos , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Ubiquitina-Proteína Ligases Nedd4/genética , Osteoartrite/patologia , Osteoartrite/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , Estabilidade de RNA , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genéticaRESUMO
PURPOSE: The aim of this study was to find an alternative method to meet traditional human anatomy teaching and clinical needs in order to solve the problem of cranial specimen attrition and specimen resource shortage due to long-term use. METHODS: We performed a computed tomography (CT) scan of a well-preserved male cranial specimen and used Mimics 19.0 software for 3D reconstruction and cranial block separation. Subsequently, we compared the recognition ability of the processed cranial digital model with that of the 3D body digital model and used 3D printing to create the cranial model and compare it with the physical specimen. RESULTS: Twenty-two cranial bone block models were obtained, excluding the hyoid bone. Their 3D reconstructed digital models had better bony landmark recognition than the 3D body human digital models, and the differences between the 3D printed models and the physical specimens were minimal. In addition, only one stereolithography (STL) file was required to produce the cranial models, which facilitates repetitive printing at any time. CONCLUSION: By isolating cranial bone blocks through 3D reconstruction techniques and preparing high-quality cranial models in combination with 3D printing techniques, this study solves the problem of shortage of cranial teaching specimens for the sustainable development of clinical and medical schools.
Assuntos
Imageamento Tridimensional , Modelos Anatômicos , Impressão Tridimensional , Crânio , Tomografia Computadorizada por Raios X , Humanos , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem , Masculino , Estereolitografia , Cadáver , SoftwareRESUMO
Ethanol, as one of the important bulk chemicals, is widely used in modern society. It can be produced by fermentation of sugar, petroleum refining, or conversion of syngas (CO/H2). Among these approaches, conversion of syngas to ethanol (STE) is the most environmentally friendly and economical process. Although considerable progress has been made in STE conversion, control of CO activation and C-C growth remains a great challenge. This review highlights recent advances in the routes and catalysts employed in STE technology. The catalyst designs and pathway designs are summarized and analysed for the direct and indirect STE routes, respectively. In the direct STE routes (i.e., one-step synthesis of ethanol from syngas), modified catalysts of methanol synthesis, modified catalysts of Fischer-Tropsch synthesis, Mo-based catalysts, noble metal catalysts and multifunctional catalysts are systematically reviewed based on their catalyst designs. Further, in the indirect STE routes (i.e., multi-step processes for ethanol synthesis from syngas via methanol/dimethyl ether as intermediates), carbonylation of methanol/dimethyl ether followed by hydrogenation, and coupling of methanol with CO to form dimethyl oxalate followed by hydrogenation, are outlined according to their pathway designs. The goal of this review is to provide a comprehensive perspective on STE technology and inspire the invention of new catalysts and pathway designs in the near future.
Assuntos
Etanol , Metanol , Catálise , Hidrogenação , Metais , Metanol/metabolismoRESUMO
The direct selective conversion of ethanol to butadiene (ETB) is a competitive and environmentally friendly process compared to the traditional crude cracking route. The acid-base properties of catalysts are crucial for the direct ETB process. Herein, we report a rationally designed multifunctional lignin-derived carbon-modulated ZnZr/SiO2 (L-ZnZr/SiO2) catalyst with suitable acid-base properties for the direct ETB reaction. A variety of characterization techniques are employed to investigate the relationship between the acid-base properties and catalytic performance of the multifunctional lignin-modulated ZnZr/SiO2 catalysts. The results revealed that the rationally additional lignin-modulated carbon enhances both the acidity and basicity of the ZnZr/SiO2 catalysts, providing a suitable acid-base ratio that boosts the direct ETB reactivity. Meanwhile, the 1% L-ZnZr/SiO2 catalyst possessed ethanol conversion and butadiene selectivity as high as 98.4% and 55.5%, respectively, and exhibited excellent catalytic stability.
RESUMO
Radiopharmaceutical dynamic imaging typically necessitates intravenous injection via the bolus method. However, manual bolus injection carries the risk of handling errors as well as radiological injuries. Hence, there is potential for automated injection devices to replace manual injection methods. In this study, the effect of micro-bolus pulse injection technology was compared and verified by radioactive experiments using a programmable injection pump, and the overall bubble recognition experiment and rat tail vein simulation injection verification were performed using the piezoelectric sensor preloading method. The results showed that at the same injection peak speed, the effective flushing volume of micro-bolus pulse flushing (about 83 µL/pulse) was 49.65% lower than that of uniform injection and 25.77% lower than that of manual flushing. In order to avoid the dilution effect of long pipe on the volume of liquid, the use of piezoelectric sensor for sealing preloading detection could accurately predict the bubbles of more than 100 µL in the syringe. In the simulated injection experiment of rat tail vein, when the needle was placed in different tissues by preloading 100 µL normal saline, the piezoelectric sensor fed back a large difference in pressure attenuation rate within one second, which was 2.78% in muscle, 17.28% in subcutaneous and 54.71% in vein. Micro-bolus pulse injection method and piezoelectric sensor sealing preloading method have application potential in improving the safety of radiopharmaceutical automatic bolus injection.
Assuntos
Compostos Radiofarmacêuticos , Animais , Ratos , Compostos Radiofarmacêuticos/administração & dosagemRESUMO
In clinical practice, radiopharmaceutical dynamic imaging technology requires the bolus injection method to complete injection. Due to the failure rate and radiation damage of manual injection, even experienced technicians still bear a lot of psychological burden. This study combined the advantages and disadvantages of various manual injection modes to develop the radiopharmaceutical bolus injector, and explored the application of automatic injection in the field of bolus injection from four aspects: radiation protection, occlusion response, sterility of injection process and effect of bolus injection. Compared with the current mainstream manual injection method, the bolus manufactured by the radiopharmaceutical bolus injector based on the automatic hemostasis method had a narrower full width at half maximum and better repeatability. At the same time, radiopharmaceutical bolus injector had reduced the radiation dose of the technician's palm by 98.8%, and ensured more efficient vein occlusion recognition performance and sterility of the entire injection process. The radiopharmaceutical bolus injector based on automatic hemostasis has application potential in improving the effect and repeatability of bolus injection.
Assuntos
Mãos , Compostos Radiofarmacêuticos , InjeçõesRESUMO
The conversion of CO2 into ethanol with renewable H2 has attracted tremendous attention due to its integrated functions of carbon elimination and chemical synthesis, but remains challenging. The electronic properties of a catalyst are essential to determine the adsorption strength and configuration of the key intermediates, therefore altering the reaction network for targeted synthesis. Herein, we describe a catalytic system in which a carbon buffer layer is employed to tailor the electronic properties of the ternary ZnOx -Fe5 C2 -Fe3 O4 , in which the electron-transfer pathway (ZnOx âFe species or carbon layer) ensures the appropriate adsorption strength of -CO* on the catalytic interface, facilitating C-C coupling between -CHx * and -CO* for ethanol synthesis. Benefiting from this unique electron-transfer buffering effect, an extremely high ethanol yield of 366.6â gEtOH kgcat -1 h-1 (with CO of 10â vol % co-feeding) is achieved from CO2 hydrogenation. This work provides a powerful electronic modulation strategy for catalyst design in terms of highly oriented synthesis.
RESUMO
The non-petroleum synthesis route of ethanol from syngas (H2 +CO) with methyl acetate (MA) as the core intermediate product has been confirmed as an excellent industrialization route for high purity ethanol production. However, as the central part of this tandem-catalysis path, the carbonylation of dimethyl ether (DME) to MA is limited by the undesirable catalytic activity and stability of zeolite catalysts. Herein, a facile inhibitor-assisted strategy was developed for constructing self-assembled nano-Mordenite (nano-MOR) zeolites without using any expensive or complex template. A nano-filamentous MOR zeolite with only 70â nm crystal diameter was successfully synthesized by selectively controlling the crystal growth orientation with a specific inhibitor. The catalytic performance of self-assembled nano-MOR catalysts was remarkably outstanding in DME carbonylation reaction. The highest Space-Time Yield (STY) of MA was achieved over Nanofilament MOR (NF-MOR), which was significantly improved comparing with that of the traditional Ellipsoid-MOR (ES-MOR) [3780â mmol/(kg â h) vs. 1368â mmol/(kg â h)]. One-step ethanol synthesis was realized by combining the MOR catalyst and an innovative self-reduced Cu-ZnO/SiO2 (CZ/SiO2 ) catalyst in a rationally designed dual-bed catalysis system. Adopting the tailor-made NF-MOR&CZ/SiO2 combination, it obtained the highest STY of ethanol, about 4 times of the conventional ES-MOR&CZ combination [1800â mmol/(kg â h) vs. 476â mmol/(kg â h)]. The present self-assembled nano-MOR zeolites synthetic strategy opens a new way for the fabrication of high-performance zeolites for practical industrial applications in catalytic conversions of one-carbon (C1) small molecules to high value-added chemicals.
RESUMO
CBF transcription factors (TFs) are key regulators of plant stress tolerance and play an integral role in plant tolerance to adverse growth environments. However, in the current research situation, there are few reports on the response of the CBF gene to Begonia stress. Therefore, this experiment investigated a novel CBF TF gene, named MbCBF2, which was isolated from M. baccata seedlings. According to the subcellular localization results, the MbCBF2 protein was located in the nucleus. In addition, the expression level of MbCBF2 was higher in new leaves and roots under low-temperature and high-salt induction. After the introduction of MbCBF2 into Arabidopsis thaliana, the adaptability of transgenic A. thaliana to cold and high-salt environments was significantly enhanced. In addition, the high expression of MbCBF2 can also change many physiological indicators in transgenic A. thaliana, such as increased chlorophyll and proline content, superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activity, and reduced malondialdehyde (MDA) content. Therefore, it can be seen from the above results that MbCBF2 can positively regulate the response of A. thaliana to low-temperature and osmotic stress. In addition, MbCBF2 can also regulate the expression of its downstream genes in transgenic lines. It can not only positively regulate the expression of the downstream key genes AtCOR15a, AtERD10, AtRD29a/b and AtCOR6.6/47, related to cold stress at low temperatures, but can also positively regulate the expression of the downstream key genes AtNCED3, AtCAT1, AtP5CS, AtPIF1/4 and AtSnRK2.4, related to salt stress. That is, the overexpression of the MbCBF2 gene further improved the adaptability and tolerance of transgenic plants to low-temperature and high-salt environments.
Assuntos
Arabidopsis , Malus , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Malus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Salino , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
The MYB transcription factor (TF) family is one of the largest transcription families in plants, which is widely involved in the responses of plants to biotic and abiotic stresses, as well as plant growth, development, and metabolic regulation. In the present study, a new MYB TF gene, MbMYB108, from Malus baccata (L.) Borkh, was identified and characterized. The open reading frame (ORF) of MbMYB108 was found to be 903 bp, encoding 300 amino acids. Sequence alignment results and predictions of the protein structure indicated that the MbMYB108 protein contained the conserved MYB domain. Subcellular localization showed that MbMYB108 was localized to the nucleus. The expression of MbMYB108 was enriched in young and mature leaves, and was highly affected by cold and drought treatments in M. baccata seedlings. When MbMYB108 was introduced into Arabidopsis thaliana, it greatly increased the cold and drought tolerances in the transgenic plant. Increased expression of MbMYB108 in transgenic A. thaliana also resulted in higher activities of peroxidase (POD) and catalase (CAT), higher contents of proline and chlorophyll, while malondialdehyde (MDA) content and relative conductivity were lower, especially in response to cold and drought stresses. Therefore, these results suggest that MbMYB108 probably plays an important role in the response to cold and drought stresses in A. thaliana by enhancing the scavenging capability for reactive oxygen species (ROS).
Assuntos
Arabidopsis , Malus , Arabidopsis/metabolismo , Clonagem Molecular , Secas , Regulação da Expressão Gênica de Plantas , Humanos , Malus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
In the natural environment, plants often face unfavorable factors such as drought, cold, and freezing, which affect their growth and yield. The MYB (v-myb avian myeloblastosis viral oncogene homolog) transcription factor family is widely involved in plant responses to biotic and abiotic stresses. In this study, Malus baccata (L.) Borkh was used as the research material, and a gene MbMYB4 of the MYB family was cloned from it. The open reading frame (ORF) of MbMYB4 was found to be 762 bp, encoding 253 amino acids; sequence alignment results and predictions of the protein structure indicated that the MbMYB4 protein contained the conserved MYB domain. Subcellular localization showed that MbMYB4 was localized in the nucleus. In addition, the use of quantitative real-time PCR (qPCR) technology found that the expression of MbMYB4 was enriched in the young leaf and root, and it was highly affected by cold and drought treatments in M. baccata seedlings. When MbMYB4 was introduced into Arabidopsis thaliana, it greatly increased the cold and drought tolerance in the transgenic plant. Under cold and drought stresses, the proline and chlorophyll content, and peroxidase (POD) and catalase (CAT) activities of transgenic A. thaliana increased significantly, and the content of malondialdehyde (MDA) and the relative conductivity decreased significantly, indicating that the plasma membrane damage of transgenic A. thaliana was lesser. Therefore, the overexpression of the MbMYB4 gene in A. thaliana can enhance the tolerance of transgenic plants to cold and drought stresses.
Assuntos
Arabidopsis , Malus , Sequência de Aminoácidos , Arabidopsis/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Malus/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/metabolismoRESUMO
In this study, we aimed to investigate the changes of lymphocyte subsets (CD3+ , CD4+ , CD8+ ) and inflammatory factors (interleukin-6 [IL-6], hypersensitive C-reactive protein [HS-CRP], and procalcitonin [PCT]) of alveolar lavage fluid in patients with severe corona virus-2019 (COVID-19) pneumonia and their clinical impact on the assessment of disease severity and prognosis. Twenty-four patients with severe COVID-19 pneumonia were admitted to the intensive care unit (ICU) of the Ezhou Central Hospital from February 1 to March 22, 2020. According to the 28-day prognosis, they were assigned to a death group and a survival group. On the 3rd day of ICU admission, peripheral blood and alveolar lavage fluid were collected for examination of lymphocyte subsets and inflammatory factors by flow cytometry and immunoturbidimetry, respectively. The CD3+ , CD4+ , and CD8+ cell counts in alveolar lavage fluid and serum were significantly higher in the survival group than those of the death group (p < .05). The levels of IL-6, HS-CRP, and PCT in the alveolar lavage fluid and serum of the death group were statistically higher than those of the survival group (p < .05); The CD3+ , CD4+ cell count, and IL-6 level were negatively correlated with Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II scores, respectively (p < .05). The CD4+ cell and SOFA score have a regression relationship for the prognosis of COVID-19 severe patients. The CD3+ , CD4+ , CD8+ cells, and IL-6 levels are valuable in determining the prognosis of severe COVID-19 pneumonia and are strongly correlated with the severity of the disease; the CD4+ cell is an independent risk factor affecting the prognosis of COVID-19 pneumonia.
Assuntos
Líquido da Lavagem Broncoalveolar/imunologia , COVID-19/imunologia , COVID-19/patologia , Adulto , Idoso , Biomarcadores/metabolismo , COVID-19/diagnóstico , Feminino , Humanos , Imunidade Celular , Inflamação , Unidades de Terapia Intensiva , Contagem de Linfócitos , Subpopulações de Linfócitos/citologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , SARS-CoV-2 , Índice de Gravidade de DoençaRESUMO
Pulsed Lidar can obtain rich target information in one pulse, but the echo pulse signal is extremely susceptible to low laser transmitting power and complex target environments, resulting in an amplitude that is too low, which affects detection efficiency and ranging accuracy. In this paper, a variational modal decomposition based on gray wolf optimizer (VMD-GWO) and an empirical mode decomposition (EMD) parallel for denoising and signal enhancement in pulse Lidar is proposed and demonstrated completely. First, the adaptive strategy EMD is used for denoising the signal to obtain effective information. The combination of optimal VMD parameters of quadratic penalty αv and decomposition mode k was obtained by using the GWO to select the modal component with the smallest center frequency as effective information. Second, EMD and VMD-GWO parallel optimization algorithms are used to reconstruct the signal to obtain denoising and enhanced signals. Finally, a real experiment was carried out with the pulse Lidar ranging equipment. Our method compared with EMD-soft, EMD-VMD,WL-db4//EMD-DT and WL-db4//VMD has achieved greater improvement. When the target distance and the reflectivity of the reflectivity plate are 30 m and 10%, respectively, the peak signal-to-noise ratio (PSNR) of the weak echo signal calculated by our method can reach 11.5284â dB. And when in the dead zone of the system ranging, it is effectively denoising and enhancing the signal.
RESUMO
Owing to its novel electronic and magnetic properties, two-dimensional CrI3 has great potential in the application of spintronic devices. However, as an inevitable line defect, the properties of the edges of CrI3 remain elusive. Here, via first-principles calculations with spin-orbit coupling, we investigated the thermodynamic stabilities, electronic and magnetic properties of thirteen CrI3 edges with different structures. We showed that zigzag edges are more stable than armchair edges, and a CrI3 nanoribbon can be either metallic or insulating depending on its chemical growth conditions. The edge stability and associated electronic properties can be understood in terms of the octahedron ligand field and electron counting model. In most cases, both the magnetic moment and Curie temperature can be enhanced by edges, which are in startle contrast to the surfaces of three-dimensional ferromagnetic materials, where a magnetic dead layer is often observed.
RESUMO
In this paper, we propose an all-solid-state and ultralow sidelobe optical phased array (OPA) through designing a broadband angle-insensitive reflective metasurface in the midinfrared. The simulation results show that the metasurface can realize the wide-frequency metareflection characteristics in the range of 4.3â¼5.0µm. Notably, the metasurface array can almost generate a continuous sweep between 0° and 342°, while the variation of reflectivity amplitude is only 10.2%, by changing the corresponding structural parameters. Then, we design and simulate an OPA based on these excellent characteristics of the broadband metasurface. By simply changing the periodicity of the OPA structure, the continuous deflection angles can be achieved within 29.41°, which can increase to 44.06° by changing the angle of the incident beam. A key feature of our design is that the sidelobe energy is less than 3.10% of the main lobe energy.