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Glioma, a prevalent primary tumor of the central nervous system, is targeted by molecular therapies aiming to intervene in specific genes and signaling pathways to inhibit tumor growth and spread. Our previous bioinformatics study revealed that significant CDC6 overexpression in gliomas was closely correlated with poor patient prognosis. Through qPCR, western blotting, and immunohistochemistry, we will further validate CDC6 expression in clinical glioma specimens, while the effects of silencing and overexpressing CDC6 in the U87 and LN229 glioma cell lines on malignancy will be assessed through MTS, EdU, transwell, and migration assays. Luciferase reporter assays, ChIP, qPCR, and western blotting were used to explore the upstream and downstream molecular mechanisms of CDC6. Our study confirmed the abnormal overexpression of CDC6 in gliomas, particularly in glioblastomas. CDC6 promotes glioma cell activity, proliferation, invasion, and migration by activating the IL6-mediated JAK2/STAT3 signaling pathway. The transcription Factor E2F8 directly regulates CDC6 transcription, playing a crucial role in its abnormal overexpression in gliomas. This research provides vital evidence supporting CDC6 as a molecular target for glioma therapy.
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OBJECTIVES: To observe the clinical efficacy of modified cervical Jiaji acupuncture in the treatment of mixed cervical spondylosis (MCS). METHODS: In this retrospective study, 120 patients with MCS who were treated in Yongchuan Hospital, Affiliated with Chongqing Medical University, from May 2020 to May 2023, were selected as the study subjects. According to the treatment methods, 52 patients who were treated with ordinary seat traction, tendon manipulation and ironing from January 2020 to December 2021 were grouped as the traditional treatment group. From January 2022 to December 2023, 68 patients who were treated with acupuncture at cervical Jiaji points formed the acupuncture group. Cervical Jiaji points (EX-B2) are located on both sides of the spinous process from the first to the seventh cervical vertebra, 0.5 inch lateral to the posterior median line, with 7 points on one side, and a total of 14 points. The patients were in a prone position and the points were treated using direct needling with filiform needle and reinforcing-reducing manipulation. Both groups were treated for 2 weeks. The pain, pain intensity, pain improvement quality, blood flow improvement, cervical spine mobility, cervical spine function and clinical efficacy of the two groups before and after treatment were compared. RESULTS: After treatment, the pain rating index (PRI) score, present pain intensity (PPI) score and visual analogue scale (VAS) score of the two groups all decreased, with those in the acupuncture group decreasing more substantially than that in the traditional treatment group (all P < 0.05). The mean blood flow velocity (Vm) in the right vertebral artery, left vertebral artery and basilar artery in the acupuncture group were significantly higher than in the traditional treatment group (all P < 0.05). The right-handed, left-handed, posterior, anteflexion, left-flexion and right-flexion activities of the acupuncture group were better than in the traditional treatment group (all P < 0.05), and the neck disability index (NDI) score and clinical assessment scale for cervical spondylosis (CASCS) scores of in the acupuncture group were better than the traditional treatment group (all P < 0.05). After therapy, the total effective rate of the acupuncture group was 86.67%, which was significantly higher than 71.67% in the traditional treatment group (P < 0.05). CONCLUSION: Modified cervical Jiaji acupuncture is effective in treating MCS. It can improve the clinical symptoms, cervical spine function and cervical spine mobility, and reduce the intensity of pain.
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Sorghum (Sorghum bicolor), the fifth most important cereal crop globally, serves as a staple food, animal feed, and a bioenergy source. Paclobutrazol-Resistance (PRE) genes play a pivotal role in the response to environmental stress, yet the understanding of their involvement in pest resistance remains limited. In the present study, a total of seven SbPRE genes were found within the sorghum BTx623 genome. Subsequently, their genomic location was studied, and they were distributed on four chromosomes. An analysis of cis-acting elements in SbPRE promoters revealed that various elements were associated with hormones and stress responses. Expression pattern analysis showed differentially tissue-specific expression profiles among SbPRE genes. The expression of some SbPRE genes can be induced by abiotic stress and aphid treatments. Furthermore, through phytohormones and transgenic analyses, we demonstrated that SbPRE4 improves sorghum resistance to aphids by accumulating jasmonic acids (JAs) in transgenic Arabidopsis, giving insights into the molecular and biological function of atypical basic helix-loop-helix (bHLH) transcription factors in sorghum pest resistance.
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Afídeos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Sorghum , Estresse Fisiológico , Triazóis , Sorghum/genética , Sorghum/metabolismo , Afídeos/genética , Afídeos/fisiologia , Animais , Triazóis/farmacologia , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Arabidopsis/genética , Regiões Promotoras Genéticas , Família Multigênica , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Filogenia , Doenças das Plantas/parasitologia , Doenças das Plantas/genética , Genoma de PlantaRESUMO
Objective: Genomic alterations and potential neoantigens for cervical cancer immunotherapy were identified in a cohort of Chinese patients with cervical squamous cell carcinoma (CSCC). Methods: Whole-exome sequencing was used to identify genomic alterations and potential neoantigens for CSCC immunotherapy. RNA Sequencing was performed to analyze neoantigen expression. Results: Systematic bioinformatics analysis showed that C>T/G>A transitions/transversions were dominant in CSCCs. Missense mutations were the most frequent types of somatic mutation in the coding sequence regions. Mutational signature analysis detected signature 2, signature 6, and signature 7 in CSCC samples. PIK3CA, FBXW7, and BICRA were identified as potential driver genes, with BICRA as a newly reported gene. Genomic variation profiling identified 4,960 potential neoantigens, of which 114 were listed in two neoantigen-related databases. Conclusion: The present findings contribute to our understanding of the genomic characteristics of CSCC and provide a foundation for the development of new biotechnology methods for individualized immunotherapy in CSCC.
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Carcinoma de Células Escamosas , Imunoterapia , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/imunologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/imunologia , Estudos de Coortes , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Pessoa de Meia-Idade , Sequenciamento do Exoma , China , Mutação , Adulto , Genômica , População do Leste AsiáticoRESUMO
In layered Li-rich materials, over stoichiometric Li forms an ordered occupation of LiTM6 in transition metal (TM) layer, showing a honeycomb superstructure along [001] direction. At the atomic scale, the instability of the superstructure at high voltage is the root cause of problems such as capacity/voltage decay of Li-rich materials. Here a Li-rich material with a high Li/Ni disorder is reported, these interlayer Ni atoms locate above the honeycomb superstructure and share adjacent O coordination with honeycomb TM. These NiâO bonds act as cable-stayed bridge to the honeycomb plane, and improve the high-voltage stability. The cable-stayed honeycomb superstructure is confirmed by in situ X-ray diffraction to have a unique cell evolution mechanism that it can alleviate interlaminar lattice strain by promoting in-plane expansion along a-axis and inhibiting c-axis stretching. Electrochemical tests also demonstrate significantly improved long cycle performance after 500 cycles (86% for Li-rich/Li half cell and 82% for Li-rich/Si-C full cell) and reduced irreversible oxygen release. This work proves the feasibility of achieving outstanding stability of lithium-rich materials through superstructure regulation and provides new insights for the development of the next-generation high-energy-density cathodes.
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Plant growth and development are driven by intricate processes, with the cell membrane serving as a crucial interface between cells and their external environment. Maintaining balance and signal transduction across the cell membrane is essential for cellular stability and a host of life processes. Ion channels play a critical role in regulating intracellular ion concentrations and potentials. Among these, K+ channels on plant cell membranes are of paramount importance. The research of Shaker K+ channels has become a paradigm in the study of plant ion channels. This study offers a comprehensive overview of advancements in Shaker K+ channels, including insights into protein structure, function, regulatory mechanisms, and research techniques. Investigating Shaker K+ channels has enhanced our understanding of the regulatory mechanisms governing ion absorption and transport in plant cells. This knowledge offers invaluable guidance for enhancing crop yields and improving resistance to environmental stressors. Moreover, an extensive review of research methodologies in Shaker K+ channel studies provides essential reference solutions for researchers, promoting further advancements in ion channel research.
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Soil salinization poses a mounting global ecological and environmental threat. The identification of genes responsible for negative regulation of salt tolerance and their utilization in crop improvement through gene editing technologies emerges as a swift strategy for the effective utilization of saline-alkali lands. One efficient mechanism of plant salt tolerance is maintaining the proper intracellular K+/Na+ ratio. The Shaker K+ channels play a crucial role in potassium absorption, transport, and intracellular potassium homeostasis in plant cells. Here, the study presents the first genome-wide identification of Shaker K+ channels in Nicotiana tabacum L., along with a detailed bioinformatic analysis of the 20 identified members. Transcriptome analysis revealed a significant up-regulation of NtSKOR1B, an outwardly-rectifying member predominantly expressed in the root tissue of tobacco seedlings, in response to salt stress. This finding was then confirmed by GUS staining of ProNtSKOR1B::GUS transgenic lines and RT-qPCR analysis. Subsequently, NtSKOR1B knockout mutants (ntskor1) were then generated and subjected to salt conditions. It was found that ntskor1 mutants exhibit enhanced salt tolerance, characterized by increased biomass, higher K+ content and elevated K+/Na+ ratios in both leaf and root tissues, compared to wild-type plants. These results indicate that NtSKOR1B knockout inhibits K+ efflux in root and leaf tissues of tobacco seedlings under salt stress, thereby maintaining higher K+/Na+ ratios within the cells. Thus, our study identifies NtSKOR1B as a negative regulator of salt tolerance in tobacco seedlings.
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Salinity stands as a significant environmental stressor, severely impacting crop productivity. Plants exposed to salt stress undergo physiological alterations that influence their growth and development. Meanwhile, plants have also evolved mechanisms to endure the detrimental effects of salinity-induced salt stress. Within plants, Calcineurin B-like (CBL) proteins act as vital Ca2+ sensors, binding to Ca2+ and subsequently transmitting signals to downstream response pathways. CBLs engage with CBL-interacting protein kinases (CIPKs), forming complexes that regulate a multitude of plant growth and developmental processes, notably ion homeostasis in response to salinity conditions. This review introduces the repercussions of salt stress, including osmotic stress, diminished photosynthesis, and oxidative damage. It also explores how CBLs modulate the response to salt stress in plants, outlining the functions of the CBL-CIPK modules involved. Comprehending the mechanisms through which CBL proteins mediate salt tolerance can accelerate the development of cultivars resistant to salinity.
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Calcineurina , Proteínas de Plantas , Proteínas de Plantas/metabolismo , Calcineurina/metabolismo , Proteínas Quinases/metabolismo , Estresse Salino , Estresse Fisiológico , Proteínas de Ligação ao Cálcio/metabolismoRESUMO
Lysimachiacavicola (Subgen. Idiophyton, Primulaceae), a new species from Guangxi, China, is here described and illustrated based on morphological data. Although it shares similarities with L.microcarpa, L.fooningensis, and L.capillipes, there are distinguishing characteristics that set it apart. These include erect stems either solitary or in clusters of 1 to 2, herbaceous, terete, and densely glandular hairy. The leaves are either ovate or elliptical lanceolate, with inconspicuously reticulate veins. The petiole measures 2-4 mm in length covered with minute glandular hairy. The corolla is deeply parted, measuring 6-8 mm in length, with narrowly elliptic or narrowly oblong lobes that are 1-2 mm wide. The capsule is globose, measuring 2-3 × 2-3 mm, and possesses a chalky, brittle texture, which splits into 5-valved segments. The calyx of the plant appears yellowish-white during fruiting. This newly discovered species is endemic to limestone areas in Fengshan County, Guangxi, China.
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Chemical oxygen demand (COD) is an important indicator for monitoring the quality of seawater. The COD of seawater reflects the levels of organic pollutants in the water. Methods that are commonly used to measure the COD of seawater have high accuracy, good repeatability, and low costs. However, using them for the in situ real-time monitoring of the COD of seawater is unfavorable because they require complex procedures and a long measurement time and may cause pollution to the environment. This paper reports on an optical sensor that accurately determines the COD of seawater in situ. The COD determination is based on the absorption of ultraviolet and visible lights with different wavelengths by organic matter in the water. Single-point LEDs emitting lights with different wavelengths (254, 265, 280, and 546 nm) were used as sources of excitation lights, and photodiodes were used as receiving devices. The optical system, circuit system, and mechanical structure of the sensor were efficiently integrated. The inversion of the COD of seawater was obtained after turbidity correction using the multiple linear regression algorithm. The maximum measurement error, detection limit, and repeatability of the sensor were 5%, 0.05 mg/l, and 0.62%, respectively. Moreover, the R2 values for correlations between COD values and absorbance values measured at three wavelengths (254, 265, and 280 nm) were above 0.99. Overall, the sensor is suitable for the in situ real-time monitoring of the COD of seawater. It requires a short measurement time and generates no pollution.
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BACKGROUND: Hepatic arterioportal fistulas (APFs) are common in hepatocellular carcinoma (HCC). Moreover, correlated with poor prognosis, APFs often complicate anti-tumor treatments, including transarterial chemoembolization (TACE). AIM: To compare the efficacy of ethanol-soaked gelatin sponges (ESG) and microspheres in the management of APFs and their impact on the prognosis of HCC. METHODS: Data from patients diagnosed with HCC or hepatic APFs between June 2016 and December 2019 were retrospectively analyzed. Furthermore, APFs were embolized with ESG (group E) or microspheres (group M) during TACE. The primary outcomes were disease control rate (DCR) and objective response rate (ORR). The secondary outcomes included immediate and first follow-up APF improvement, overall survival (OS), and progression-free survival (PFS). RESULTS: Altogether, 91 participants were enrolled in the study, comprising 46 in group E and 45 in group M. The DCR was 93.5% and 91.1% in groups E and M, respectively (P = 0.714). The ORRs were 91.3% and 66.7% in groups E and M, respectively (P = 0.004). The APFs improved immediately after the procedure in 43 (93.5%) patients in group E and 40 (88.9%) patients in group M (P = 0.485). After 2 mo, APF improvement was achieved in 37 (80.4%) and 33 (73.3%) participants in groups E and M, respectively (P = 0.421). The OS was 26.2 ± 1.4 and 20.6 ± 1.1 mo in groups E and M, respectively (P = 0.004), whereas the PFS was 16.6 ± 1.0 and 13.8 ± 0.7 mo in groups E and M, respectively (P = 0.012). CONCLUSION: Compared with microspheres, ESG embolization demonstrated a higher ORR and longer OS and PFS in patients of HCC with hepatic APFs.
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This study used automatic control methods to prepare gold nanoparticles (AuNPs) as the substrate and rhodamine 6G molecule as the probe to investigate the enhancement effect, stability, and consistency of surface-enhanced Raman spectroscopy (SERS). The gold nanosols were prepared via automatic control using loop flow-reactor technology, and the synthesis of nanoparticles with different sizes was precisely controlled by optimizing the ratio of the solution required for the reaction between sodium citrate and chloroauric acid during the preparation process. The morphology, structure, and optical properties of the prepared AuNPs were investigated using field-emission scanning electron microscopy, transmission electron microscopy, and ultraviolet visible spectroscopy. Using the proposed method, AuNPs with average particle sizes of 72, 85, 93, and 103â nm were synthesized in a precisely controlled manner. The 93â nm particles exhibited good SERS activity for rhodamine 6G under 785â nm excitation with a detection limit of 2.5 × 10-10â M. The relative standard deviation of the SERS spectra synthesized multiple times was <3.5%, indicating their good sensitivity and reproducibility. The results showed that the AuNPs prepared by the automatic control of the loop-flow method have high sensitivity, stability, and reproducibility. Moreover, they exhibited notable potential for in situ measurement and quantitative analysis using SERS.
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PURPOSE: This study aimed to explore the survival significance of surgery and age on the prognosis of patients with primary trachea malignancies. METHODS: The entire cohort of 637 patients with primary malignant trachea tumors was used to perform the main analyses. The data of those patients were from a public database. Overall survival (OS) curves were drawn by the Kaplan-Meier method and compared by the Log-rank test. The univariable and multivariable Cox regression analyses calculated the hazard ratio (HR) and 95% confidence interval (CI) for overall mortality. The propensity-score matching analysis was used to reduce the selection bias. RESULTS: Age, surgery, histological type, N classification, M classification, marital status, and tumor grading were identified as independent prognostic factors after eliminating confounding factors. The results of the Kaplan-Meier method revealed that patients with age < 65 had a survival advantage over those with age ≥ 65 (HR = 1.908, 95% CI 1.549-2.348, P < 0.001). The 5-year OS rates were 28% and 8% in the group with age < 65 and age ≥ 65, respectively (P < 0.001). Cases with surgery had better survival over patients without surgery (HR = 0.372, 95% CI 0.265-0.522, P < 0.001). Compared with patients who did not undergo operations, patients with surgery had a higher median survival time (20 vs. 174 months). For patients with surgery, young age was considered a survival-promoting factor (HR 2.484; 95% CI 1.238-4.983, P = 0.010). CONCLUSION: We suggested that age and surgery were the independent prognostic factors in patients with primary malignant trachea tumors. Besides, age serves as an essential indicator for evaluating the prognosis of postoperative patients.
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Neoplasias , Traqueia , Humanos , Estudos Retrospectivos , Traqueia/cirurgia , Bases de Dados Factuais , Estado CivilRESUMO
Although NIR-II laser-mediated photothermal therapy (PTT) is considered as an emerging strategy for tumor therapy, its therapeutic effects are still seriously hampered by low photothermal conversion efficacy, limited tissue penetration depth, and inevitable damage to adjoining healthy tissues. Herein, we report a mild second-near-infrared (NIR-II) photothermal-augmented nanocatalytic therapy (NCT) nanoplatform based on CD@Co3O4 heterojunctions by depositing NIR-II-responsive carbon dots (CDs) onto the surface of Co3O4 nanozymes. The as-prepared Co3O4 nanozymes possess multi-enzyme-mimicking catalytic activity including peroxidase, catalase, and glutathione-peroxidase to realize the cascade amplification of ROS levels owing to the presence of multivalent Co2+ and Co3+. CDs with a high NIR-II photothermal conversion efficiency (PCE) (51.1%) enable the realization of mild PTT (â¼43 °C), which could not only avoid damage to adjoining healthy tissues but also enhance the multi-enzyme-mimic catalytic activity of Co3O4 nanozymes. More importantly, the NIR-II photothermal properties of CDs and the multi-enzyme-mimicking catalytic activity of Co3O4 nanozymes are greatly augmented by the fabrication of heterojunctions due to the induced localized surface plasmonic resonance (LSPR) and accelerated carrier transfer. On the basis of these advantages, satisfactory mild PTT-amplified NCT is accomplished. Our work presents a promising approach for mild NIR-II photothermal-amplified NCT based on semiconductor heterojunctions.
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Carbono , Terapia Fototérmica , Linhagem Celular Tumoral , PeroxidasesRESUMO
OBJECTIVE: Drug-resistant epilepsy (DRE) can have devastating consequences for patients and families. Vagal nerve stimulation (VNS) is used as a surgical adjunct for treating DRE not amenable to surgical resection. Although VNS is generally safe, it has its inherent complications. With the increasing number of implantations, adequate patient education with discussion of possible complications forms a critical aspect of informed consent and patient counseling. There is a lack of large-scale reviews of device malfunction, patient complaints, and surgically related complications available to date. MATERIALS AND METHODS: Complications associated with VNS implants performed between 2011 and 2021 were identified through a search of the United States Food and Drug Administration Manufacturer And User Facility Device Experience (MAUDE) data base. We found three models on the data base, CYBERONICS, INC pulse gen Demipulse 103, AspireSR 106, and SenTiva 1000. The reports were classified into three main groups, "Device malfunction," "Patient complaints," and "Surgically managed complications." RESULTS: A total of 5888 complications were reported over the ten-year period, of which 501 reports were inconclusive, 610 were unrelated, and 449 were deaths. In summary, there were 2272 reports for VNS 103, 1526 reports for VNS 106, and 530 reports for VNS 1000. Within VNS 103, 33% of reports were related to device malfunction, 33% to patient complaints, and 34% to surgically managed complications. For VNS 106, 35% were related to device malfunction, 24% to patient complaints, and 41% to surgically managed complications. Lastly, for VNS 1000, 8% were device malfunction, 45% patient complaints, and 47% surgically managed complications. CONCLUSION: We present an analysis of the MAUDE data base for adverse events and complications related to VNS. It is hoped that this description of complications and literature review will help promote further improvement in its safety profile, patient education, and management of both patient and clinician expectations.
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Nitrate ( NO 3 - ) transporters have been identified as the primary targets involved in plant nitrogen (N) uptake, transport, assimilation, and remobilization, all of which are key determinants of nitrogen use efficiency (NUE). However, less attention has been directed toward the influence of plant nutrients and environmental cues on the expression and activities of NO 3 - transporters. To better understand how these transporters function in improving plant NUE, this review critically examined the roles of NO 3 - transporters in N uptake, transport, and distribution processes. It also described their influence on crop productivity and NUE, especially when co-expressed with other transcription factors, and discussed these transporters' functional roles in helping plants cope with adverse environmental conditions. We equally established the possible impacts of NO 3 - transporters on the uptake and utilization efficiency of other plant nutrients while suggesting possible strategic approaches to improving NUE in plants. Understanding the specificity of these determinants is crucial to achieving better N utilization efficiency in crops within a given environment.
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This study aimed to determine the efficiency of ultraviolet (UV)-LED cold light treatment on the degradation of aflatoxin (AF)B1 in peanut oils. The peanut oil samples obtained from different places in China and abroad were determined for AFB1 degradation efficiency of the UV-LED cold-light irradiation method. The degradation products were analyzed by ultra-high performance liquid chromatography coupled to quadrupole orbitrap high-resolution mass spectrometry (UPLC-Q-Exactive MS). The results indicated that the AFB1 content in all peanut oil samples decreased rapidly after 5 min of irradiation. Four main photodegradation products (C18H16O7, C17H14O7, C17H14O7, and C17H14O8) were identified using the established LC-MS method. Their chemical structures were postulated based on the LC-MS data. Also, the degradation pathways were proposed based on the data obtained. Oxidation and reduction reactions were mainly responsible for AFB1-decomposition. The reactions occurred at the furan and lactone rings. These findings demonstrated that UV-LED cold-light irradiation was an effective method for treating AFB1- contaminated peanut oil.
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Aflatoxina B1 , Aflatoxina B1/análise , Aflatoxina B1/química , Aflatoxina B1/metabolismo , Óleo de Amendoim , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Espectrometria de Massas/métodosRESUMO
Plants have evolved to deal with different stresses during plant growth, relying on complex interactions or crosstalk between multiple signalling pathways in plant cells. In this sophisticated regulatory network, Ca2+ transients in the cytosol ([Ca2+ ]cyt ) act as major physiological signals to initiate appropriate responses. The CALCINEURIN B-LIKE PROTEIN (CBL)-CBL-INTERACTING PROTEIN KINASE (CIPK) network relays physiological signals characterised by [Ca2+ ]cyt transients during plant development and in response to environmental changes. Many studies are aimed at elucidating the role of the CBL-CIPK network in plant growth and stress responses. This review discusses the involvement of the CBL-CIPK pathways in two levels of crosstalk between plant development and stress adaptation: direct crosstalk through interaction with regulatory proteins, and indirect crosstalk through adaptation of correlated physiological processes that affect both plant development and stress responses. This review thus provides novel insights into the physiological roles of the CBL-CIPK network in plant growth and stress adaptation.
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Arabidopsis , Proteínas Quinases , Proteínas Quinases/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Desenvolvimento VegetalRESUMO
Plants utilize carbohydrates as the main energy source, but much focus has been on the impact of N and K on plant growth. Less is known about the combined impact of NH4+ and K+ nutrition on photoassimilate distribution among plant organs, and the resultant effect of such distribution on growth of tobacco seedlings, hence this study. Here, we investigated the synergetic effect of NH4+ and K+ nutrition on photoassimilate distribution, and their resultant effect on growth of tobacco seedlings. Soluble sugar and starch content peaks under moderate NH4+ and moderate K+ (2-2 mM), leading to improved plant growth, as evidenced by the increase in tobacco weight and root activity. Whereas, a drastic reduction in the above indicators was observed in plants under high NH4+ and low K+ (20-0.2 mM), due to low carbohydrate synthesis and poor photoassimilate distribution. A strong positive linear relationship also exists between carbohydrate (soluble sugar and starch) and the activities of these enzymes but not for invertase. Our findings demonstrated that NH4+ and K+-induced ion imbalance influences plant growth and is critical for photoassimilate distribution among organs of tobacco seedlings.
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In this study, low concentration of ferrous ions (Fe2+) was added into natural molybdenite (MDN) activated peroxymonosulfate (PMS) process to degrade a typical azo dye, orange G (OG). It was found that the addition of Fe2+ promoted OG degradation and simultaneously reduced the leaching of toxic Mo ions significantly. Further, the utilization efficiency of MDN was improved immensely, which was estimated from reuse experiment. MDN mainly acted as the reductant to promote cycling of Fe3+/Fe2+ redox couple through reducible sulfur and Mo(IV) on its surface. Sulfate radicals (SO4â¢-), hydroxyl radical (â¢OH) and singlet oxygen (1O2) were verified as the main reactive oxygen species responsible for OG degradation by scavenging tests and electron paramagnetic resonance. Some experiment parameters, such as MDN dosage, Fe2+ concentration, PMS concentration, initial solution pH and coexisting anion, all affected OG degradation efficiency. In a word, this work provides a new method of enhancing PMS activation by MDN using low concentration of Fe2+ for degradation of organic pollutants in water.