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In heavy metal-contaminated areas, the simultaneous occurrence of increasing microplastic pollution and persistent acid rain poses a serious threat to food security. However, the mechanisms of combined exposure to microplastics (MP) and acid rain (AR) on the toxicity of cadmium (Cd) in rice seedlings remain unclear. Our study investigated the combined effects of exposure to polyvinyl chloride microplastics and AR (pHâ¯4.0) on the toxicity of Cd (0.3, 3, and 10â¯mg/L) in rice seedlings. The results showed that at low Cd concentrations, the combined exposure had no significant effect, but at high Cd concentrations, it alleviated the effects of Cd stress. The combined application of MP and AR alleviated the inhibitory effects of Cd on seedling growth and chlorophyll content. Under high Cd concentration (10â¯mg/L), the simultaneous addition of MP and AR significantly reduced the production of reactive oxygen species (ROS), the content of malondialdehyde (MDA), and the activity of the superoxide dismutase (SOD) enzyme. Compared to AR or MP alone, the combination of MP and AR reduced root cell damage and Cd accumulation in rice seedlings. Transcriptomic analysis confirmed that under high Cd concentrations, the combination of MP and AR altered the expression levels of genes related to Cd transport, uptake, MAPK kinase, GSTs, MTs, and transcription factors, producing a synergistic effect on oxidative stress and glutathione metabolism. These results indicate that coexposure to MP and AR affects the toxicity of Cd in rice seedlings and alleviates Cd toxicity under high Cd concentrations to some extent. These findings provide a theoretical basis for evaluating the toxicological effects of microplastic and acid rain pollution on crop growth in areas contaminated with heavy metals, and are important for safe agricultural production and ecological security.
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Leaves play a crucial role in the growth and development of rice (Oryza sativa) as sites for the production of photosynthesis. Early leaf senescence leads to substantial drops in rice yields. Whether and how DNA methylation regulates gene expression and affects leaf senescence remains elusive. Here, we demonstrate that mutations in rice ARGONAUTE 2 (OsAGO2) lead to premature leaf senescence, with chloroplasts in Osago2 having lower chlorophyll content and an abnormal thylakoid structure compared with those from wild-type plants. We show that OsAGO2 associates with a 24-nt microRNA and binds to the promoter region of OsNAC300, which causes DNA methylation and suppressed expression of OsNAC300. Overexpressing OsNAC300 causes the similar premature leaf senescence as Osago2 mutants and knocking out OsNAC300 in the Osago2 mutant background suppresses the early senescence of Osago2 mutants. Based on yeast one-hybrid, dual-luciferase, and electrophoresis mobility shift assays, we propose that OsNAC300 directly regulates transcription of the key rice aging gene NAC-like, activated by APETALA3/PISTILLATA (OsNAP) to control leaf senescence. Our results unravel a previously unknown epigenetic regulatory mechanism underlying leaf senescence in which OsAGO2-OsNAC300-OsNAP acts as a key regulatory module of leaf senescence to maintain leaf function.
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BACKGROUND: Pichia pastoris (Komagataella phaffii) is a promising production host, but the usage of methanol limits its application in the medicine and food industries. RESULTS: To improve the constitutive expression of heterologous proteins in P. pastoris, four new potential transcription regulators (Loc1p, Msn2p, Gsm1p, Hot1p) of the glyceraldehyde triphosphate dehydrogenase promoter (pGAP) were revealed in this study by using cellulase E4 as reporter gene. On this basis, a series of P. pastoris strains with knockout or overexpression of transcription factors were constructed and the deletion of transcription factor binding sites on pGAP was confirmed. The results showed that Loc1p and Msn2p can inhibit the activity of pGAP, while Gsm1p and Hot1p can enhance the activity of pGAP; Loc1p, Gsm1p and Hot1p can bind directly to pGAP, while Msn2p must be treated to expose the C-terminal domain to bind to pGAP. Moreover, manipulating a single transcription factor led to a 0.96-fold to 2.43-fold increase in xylanase expression. In another model protein, aflatoxin oxidase, knocking out Loc1 based on AFO-∆Msn2 strain resulted in a 0.63-fold to 1.4-fold increase in expression. It can be demonstrated that the combined use of transcription factors can further improve the expression of exogenous proteins in P. pastoris. CONCLUSION: These findings will contribute to the construction of pGAP-based P. pastoris systems towards high expression of heterologous proteins, hence improving the application potential of yeast.
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Regulação Fúngica da Expressão Gênica , Regiões Promotoras Genéticas , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Pichia/genética , Pichia/metabolismoRESUMO
OBJECTIVES: To explore the performance of multiparametric MRI-based radiomics in discriminating different human epidermal growth factor receptor 2 (HER2) expressing statuses (i.e., HER2-overexpressing, HER2-low-expressing, and HER2-zero-expressing) in breast cancer. METHODS: A total of 771 breast cancer patients from two institutions were retrospectively studied. Five-hundred-eighty-one patients from Institution I were divided into a training dataset (n1 = 407) and an independent validation dataset (n1 = 174); 190 patients from Institution II formed the external validation dataset. All patients were categorized into HER2-overexpressing, HER2-low-expressing, and HER2-zero-expressing groups based on pathologic examination. Multiparametric (including T2-weighted imaging with fat suppression [T2WI-FS], diffusion-weighted imaging [DWI], apparent diffusion coefficient [ADC], and dynamic contrast-enhanced [DCE]) MRI-based radiomics features were extracted and then selected from the training dataset using the least absolute shrinkage and selection operator (LASSO) regression. Three predictive models to discriminate HER2-overexpressing vs. others, HER2-low expressing vs. others, and HER2-zero-expressing vs. others were developed based on the selected features. The model performance was evaluated using the area under the receiver operating characteristic curve (AUC). RESULTS: Eleven radiomics features from DWI, ADC, and DCE; one radiomics feature from DWI; and 17 radiomics features from DWI, ADC, and DCE were selected to build three predictive models, respectively. In training, independent validation, and external validation datasets, radiomics models achieved AUCs of 0.809, 0.737, and 0.725 in differentiating HER2-overexpressing from others; 0.779, 0.778, and 0.782 in differentiating HER2-low-expressing from others; and 0.889, 0.867, and 0.813 in differentiating HER2-zero-expressing from others, respectively. CONCLUSIONS: Multiparametric MRI-based radiomics model may preoperatively predict HER2 statuses in breast cancer patients. CLINICAL RELEVANCE STATEMENT: The MRI-based radiomics models could be used to noninvasively identify the new three-classification of HER2 expressing status in breast cancer, which is helpful to the decision-making for HER2-target therapies. KEY POINTS: ⢠Detecting HER2-overexpressing, HER2-low-expressing, and HER2-zero-expressing status in breast cancer patients is crucial for determining candidates for anti-HER2 therapy. ⢠Radiomics features from multiparametric MRI significantly differed among HER2-overexpressing, HER2-low expressing, and HER2-zero-expressing breast cancers. ⢠Multiparametric MRI-based radiomics could preoperatively evaluate three different HER2-expressing statuses and help to determine potential candidates for anti-HER2 therapy in breast cancer patients.
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Neoplasias da Mama , Imageamento por Ressonância Magnética Multiparamétrica , Receptor ErbB-2 , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Feminino , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Adulto , Idoso , RadiômicaRESUMO
OBJECTIVE: Currently, there are discrepant results regarding the quantitative effect of psoriasis on sleep, which may, in part, be attributed to the use of non-standardised questionnaires. METHODS: The PubMed/Medline, Embase, and Cochrane databases were searched for cross-sectional, case-control or cohort studies that recruited patients with psoriasis and healthy controls and reported data regarding Pittsburgh Sleep Quality Index (PSQI) and the prevalence of sleep disturbance (SD) based on the PSQI, published from inception up to January 2023. Secondary outcomes included scores for the Insomnia Severity Index (ISI), Beck Depression Inventory (BDI), and Epworth Sleepiness Scale (ESS), and risk for restless legs syndrome (RLS). Meta-analyses using random-effects models were used for statistical analyses. RESULTS: Fifteen studies including 1274 patients with psoriasis and 775 controls were analysed. A higher PSQI (weighted mean difference [WMD] = 3.397, P < 0.001, I2 = 84.2%) and a higher risk for SD (odds ratio [OR] = 6.640, P < 0.001, I2 = 67.5%) were observed in patients with psoriasis compared with controls. Subgroup analyses revealed a greater difference in PSQI score and/or risk for SD between patients with psoriasis and controls in subgroups of psoriatic arthritis, moderate-to-severe psoriasis, shorter psoriasis duration, and younger age. Moreover, patients with psoriasis exhibited higher ISI (WMD = 2.709, P < 0.001) and BDI scores (WMD = 4.565, P = 0.001), and risk for RLS (OR = 4.689, P = 0.01). However, there was no significant difference in ESS scores (WMD = -0.229, P = 0.77) compared with controls. CONCLUSION: Psoriasis was associated with poor sleep quality and higher risk for SD, especially among patients with psoriatic arthritis, severe psoriasis, shorter duration of psoriasis, and younger age. Patients with psoriasis were also more likely to experience insomnia, RLS, and depression.
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Artrite Psoriásica , Psoríase , Síndrome das Pernas Inquietas , Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Humanos , Artrite Psoriásica/complicações , Distúrbios do Início e da Manutenção do Sono/complicações , Estudos Transversais , Psoríase/complicações , Sono , Síndrome das Pernas Inquietas/epidemiologia , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/complicações , Índice de Gravidade de DoençaRESUMO
Organ size shapes plant architecture during rice (Oryza sativa) growth and development, affecting key factors influencing yield, such as plant height, leaf size, and seed size. Here, we report that the rice Enhancer of Zeste [E(z)] homolog SET DOMAIN GROUP 711 (OsSDG711) regulates organ size in rice. Knockout of OsSDG711 produced shorter plants with smaller leaves, thinner stems, and smaller grains. We demonstrate that OsSDG711 affects organ size by reducing cell length and width and increasing cell number in leaves, stems, and grains. The result of chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) using an antitrimethylation of histone H3 lysine 27 (H3K27me3) antibody showed that the levels of H3K27me3 associated with cytokinin oxidase/dehydrogenase genes (OsCKXs) were lower in the OsSDG711 knockout line Ossdg711. ChIP-qPCR assays indicated that OsSDG711 regulates the expression of OsCKX genes through H3K27me3 histone modification. Importantly, we show that OsSDG711 directly binds to the promoters of these OsCKX genes. Furthermore, we measured significantly lower cytokinin contents in Ossdg711 plants than in wild-type plants. Overall, our results reveal an epigenetic mechanism based on OsSDG711-mediated modulation of H3K27me3 levels to regulate the expression of genes involved in the cytokinin metabolism pathway and control organ development in rice. OsSDG711 may be an untapped epigenetic resource for ideal plant type improvement.
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Histonas , Oryza , Histonas/genética , Histonas/metabolismo , Oryza/metabolismo , Tamanho do Órgão/genética , Domínios PR-SET , Metilação , Citocininas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Purpose: Stigma is common in patients with breast cancer after surgery, which has a negative impact on the quality of life (QOL). This study aimed to investigate the QOL of breast cancer patients after surgery and to analyze the multiple chains mediating effects of self-disclosure and social support between stigma and QOL. Methods: A total 292 patients of breast cancer patients after operation were recruited in this study. A questionnaire survey was conducted using the general information questionnaire, the consumer experiences of stigma questionnaire (CESQ), the distress disclosure index(DDI), the perceived social support scale(PSSS), and the functional assessment of cancer therapy-breast(FACT-B). Path analysis was conducted to test the hypothesized serial multiple mediation model. Results: The total scores of stigma, self-disclosure, social support and QOL were 15 (10 ~ 22), 39 (31 ~ 46), 58 (50 ~ 67) and 88 (74 ~ 104) respectively. QOL of breast cancer patients after the operation was negatively correlated with stigma (p < 0.01), and positively correlated with self-disclosure and social support (p < 0.01). Self-disclosure and social support played a complete mediating effect between stigma and QOL, and the total mediating effect value was 85. 87%. Conclusions: Self-disclosure and social support play a complete intermediary role between stigma and QOL. In order to improve the quality of life of patients, medical staff should pay attention to the assessment of stigma, encourage patients to express their emotions, and encourage their families and friends to respond to their expression and needs of patients.
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BACKGROUND: α-Glucosidase (AG) is a bifunctional enzyme, it has a capacity to synthesize 2-O-α-d-glucopyranosyl-l-ascorbic acid (AA-2G) from l-ascorbic acid (L-AA) and low-cost maltose under mild conditions, but it can also hydrolyze AA-2G, which leads to low synthesis efficiency of AA-2G. MAIN METHODS AND MAJOR RESULTS: This study introduces a rational molecular design strategy to regulate enzymatic reactions based on inhibiting the formation of ground state of enzyme-substrate complex. Y215 was analyzed as the key amino acid site affecting the affinity of AG to AA-2G and L-AA. For the purpose of reducing the hydrolysis efficiency of AA-2G, the mutant Y215W was obtained by analyzing the molecular docking binding energy and hydrogen bond formation between AG and the substrates. Compared with the wild-type, isothermal titration calorimetry (ITC) results showed that the equilibrium dissociation constant (KD ) of the mutant for AA-2G was doubled; the Michaelis constant (Km ) for AA-2G was reduced by 1.15 times; and the yield of synthetic AA-2G was increased by 39%. CONCLUSIONS AND IMPLICATIONS: Our work also provides a new reference strategy for the molecular modification of multifunctional enzymes and other enzymes in cascade reactions system.
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Ácido Ascórbico , alfa-Glucosidases , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo , Simulação de Acoplamento Molecular , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacologia , HidróliseRESUMO
Photosynthesis is the largest mass- and energy-conversion process on Earth, and it is the material basis for almost all biological activities. The efficiency of converting absorbed light energy into energy substances during photosynthesis is very low compared to theoretical values. Based on the importance of photosynthesis, this article summarizes the latest progress in improving photosynthesis efficiency from various perspectives. The main way to improve photosynthetic efficiency is to optimize the light reactions, including increasing light absorption and conversion, accelerating the recovery of non-photochemical quenching, modifying enzymes in the Calvin cycle, introducing carbon concentration mechanisms into C3 plants, rebuilding the photorespiration pathway, de novo synthesis, and changing stomatal conductance. These developments indicate that there is significant room for improvement in photosynthesis, providing support for improving crop yields and mitigating changes in climate conditions.
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Fotossíntese , Plantas , Plantas/metabolismo , LuzRESUMO
Presently, a variety of policies and measures has implemented to enhance the scientific research and innovation ability of medical students, but in the process of practice, there are many problems, such as they lack of independent topic selection ability, weak scientific research skills, lack of autonomous learning ability, the research results are simple and ineffective, limited teacher guidance time and so on. This paper attempted to build an effective model for the promotion of medical students' scientific research and innovation ability, in order to establish an efficacy evaluation model of the "Medical students' Innovative Scientific Research Program." Undergraduates, graduate assistants, and tutors were interviewed with the Behavioral Event Interview technique, and a questionnaire of efficacy evaluation characteristics concluded from the interviews was formed. The questionnaire was conducted on medical students in the Medical students' Innovative Scientific Research Program, and the constructed model was analyzed using reliability analysis, validity analysis, and variation analysis. At the same time, the experimental teaching models are summarized and combed, and compared with other methods such as independent sample test. The results show the model could effectively evaluate the efficacy of the Medical students' Innovative Scientific Research Program and its teaching model is effective in cultivating medical students' learning and scientific research ability. It can provide theoretical support and practical reference for the evaluation and reform of the teaching modes related to the cultivation of scientific and innovative ability of medical students.
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Estudantes de Medicina , Humanos , Reprodutibilidade dos Testes , Aprendizagem , Bioquímica , Biologia MolecularRESUMO
Background: The evidence regarding objective sleep especially for the sleep architecture in atopic dermatitis (AD) was limited and not well summarized. Objective: To determine the objective sleep in AD patients as well as its confounders. Methods: We searched PubMed/Medline, Embase, and PsycInfo up to May 2021. Case-control studies or cohort studies that recruited AD patients and healthy controls and reported objective sleep parameters assessed by polysomnography or actigraphy were included. Results: A total of 7 studies with 173 AD patients and 122 controls were analyzed. Specifically, AD patients have significantly decreased total sleep time (TST, -13.797 minutes) and sleep efficiency (SE, -5.589%) accompanied by prolonged wake time after sleep onset (WASO, 29.972 minutes) and rapid eye movement sleep latency (31.894 minutes, all P < 0.05). Furthermore, subgroup analyses showed more WASO in severe AD subgroup compared with nonsevere AD subgroup (51.323 minutes vs 20.966 minutes, P = 0.032), less SE in male-majority subgroup compared with female-majority subgroup (-9.443% vs -4.997%, P = 0.018), and less TST in adult subgroup compared with child subgroup (-41.045 vs -4.016 minutes, P = 0.037). Conclusion: Objective sleep was worse in AD patients, especially among patients with severe AD, males, and adults. AD appears to more predispose difficulty in sleep maintenance rather than falling asleep.
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Dermatite Atópica , Transtornos do Sono-Vigília , Criança , Adulto , Humanos , Masculino , Feminino , Dermatite Atópica/complicações , Sono , Polissonografia , Actigrafia , Estudos de Casos e Controles , Transtornos do Sono-Vigília/etiologiaRESUMO
As a multicomponent, multitarget empirical therapy, traditional Chinese medicine (TCM) has been used clinically in Asia for thousands of years. Due to this unique feature, TCM therapy is considered a promising therapeutic strategy for the treatment of hepatocellular carcinoma (HCC). Er-Zhi-Wan (EZW), a well-known TCM formula containing two herbs, Fructus Ligustri Lucidi (FLL, Nü-Zhen-Zi) and Ecliptae Herba (EH, Mo-Han-Lian), is commonly used in clinical practice to prevent and treat liver diseases. Modern pharmacological studies have shown that both EH and FLL can inhibit HCC proliferation. However, the pharmacological mechanism, potential targets, and clinical value of EZW in inhibiting HCC have not been fully elucidated. We used multilevel databases (Gene Expression Omnibus (GEO), Traditional Chinese Medicine Systems Pharmacology (TCMSP), High-throughput Experiment- and Reference-guided database (HERB), and SwissTargetPrediction) to show that EZW suppresses HCC through 19 active components acting on 66 potential targets. Enrichment analysis revealed that EZW mainly regulates HCC progression through various metabolic pathways, the cell cycle, and cellular senescence. Furthermore, we used The Cancer Genome Atlas (TCGA)-LIHC database to analyze the expression patterns and clinical characteristics of cellular senescence-related genes and identified CDK1, CDK4, CHEK1, and G6PD as key therapeutic molecular targets in EZW-suppressed HCC. Molecular docking revealed that EZW could exert its anti-HCC effect by binding various active components to the above cellular senescence-related genes and regulating their activities. In conclusion, we systematically revealed the potential pharmacological mechanisms and molecular targets of EZW against HCC based on multilevel data integration and a molecular docking strategy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Simulação de Acoplamento Molecular , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Genes cdcRESUMO
Grain size is one of the crucial factors determining grain yield. However, the genetic and molecular mechanisms of florigen repression complexes (FRCs) underlying grain size in rice (Oryza sativa L.) have not been reported. Here, we report that the rice CENTRORADIALIS (CEN) family member OsCEN2 (also known as Rice TFL1/CEN homolog, RCN1), a phosphatidylethanolamine-binding protein (PEBP) family protein, negatively controls grain size in rice. Overexpression of OsCEN2 led to small grains, and knockout of OsCEN2 resulted in large, heavy grains. OsCEN2 influenced grain size by restricting cell expansion in the spikelet hull and seed filling. In in vivo and in vitro experiments, OsCEN2 physically interacted with a G-box factor 14-3-3 homolog, GF14f, which negatively regulates grain size. Bimolecular fluorescence complementation and yeast two-hybrid assays revealed that GF14f directly interacts with the basic leucine zipper (bZIP) transcription factor, OsFD2. Plants overexpressing OsFD2 produced smaller and lighter grains than wild-type plants. We found that OsFD2 also influences grain size by controlling cell expansion and division in the spikelet hull. Our results reveal the molecular mechanisms of the OsCEN2-GF14f-OsFD2 regulatory module in controlling grain size. Additionally, our study provides insight into the functions of the FRC in rice and suggests a strategy for improving seed size and weight.
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Oryza , Grão Comestível/genética , Grão Comestível/metabolismo , Florígeno/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Background: Medical workers have been increasingly involved in emergent public health events, which can lead to severe stress. However, no standardized, officially recognized, unified tool exists for mental distress measurement in medical workers who experienced the public health events. Purpose: In the present study, we propose the Global Health Events-Mental Stress Scale (GHE-MSS), as a revised version of the Impact of Event Scale-Revision (IES-R), for assessment of medical workers' acute mental stress responses within one month and their chronic mental stress responses within six months after major health events. Patients and methods: The IES-R was slightly modified, developed, and its reliability and validity were tested using the Delphi survey, primary survey with 115 participants, formal survey with 300 participants, and clinical evaluation with 566 participants. Results: Exploratory factor analysis and confirmatory factor analysis confirmed a promising validity of the scale. The values of Cronbach's alpha coefficient, the Spearman-Brown coefficient, and the retested Cronbach's alpha coefficient of the scale applied for the clinical evaluation were 0.88, 0.87, and 0.98, respectively, which confirmed a good internal consistency and stability. The results of the goodness-of-fit test indicated a good adaptation of the model. A correlation analysis was conducted to assess the correlation between the GHE-MSS and the PCL-C, which had a correlation coefficient of 0.68 (P<0.01). Conclusion: GHE-MSS can be applied with a promising reliability and validity for the assessment of the acute mental stress response of medical workers experiencing public health events. This method can also be used for the screening of mental stress-associated disorders.
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Estimating the biomass of Phragmites australis (Cav.) Trin. ex Steud., i.e., a common wetland macrophyte, and the associated carbon sequestration capacity has attracted increasing attention. Hanshiqiao Wetland Nature Reserve (HWNR) is a large P. australis wetland in Beijing, China, and provides an ideal case study site for such purpose in an urban setting. In this study, an existing P. australis growth dynamics model was adapted to estimate the plant biomass, which was in turn converted to the associated carbon sequestration capacity in the HWNR throughout a typical year. To account for local differences, the modeling parameters were calibrated against the above-ground biomass (AGB) of P. australis retrieved from hyperspectral images of the study site. We also analyzed the sensitivity of the modeling parameters and the influence of environmental factors, particularly the nutrient availability, on the growth dynamics and carbon sequestration capacity of P. australis. Our results show that the maximum AGB and below-ground biomass (BGB) of P. australis in the HWNR are 2.93 × 103 and 2.49 × 103 g m-2, respectively, which are higher than the reported level from nearby sites with similar latitudes, presumably due to the relatively high nutrient availability and more suitable inundation conditions in the HWNR. The annual carbon sequestration capacity of P. australis in the HWNR was estimated to be 2040.73 gC m-2 yr-1, which was also found to be highly dependent on nutrient availability, with a 50% increase (decrease) in the constant of the nutrient availability KNP, resulting in a 12% increase (23% decrease) in the annual carbon sequestration capacity. This implies that a comprehensive management of urban wetlands that often encounter eutrophication problems to synergize the effects of nutrient control and carbon sequestration is worth considering in future practices.
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Sequestro de Carbono , Áreas Alagadas , Pequim , Biomassa , China , Poaceae , Tecnologia de Sensoriamento RemotoRESUMO
Most plant pentatricopeptide repeat (PPR) proteins localize to and function inside plastids and mitochondria. However, the function of PPRs that only localize to the cytoplasm remains unknown. Here, we demonstrated that the rice (Oryza sativa) PPR protein CYTOPLASM-LOCALIZED PPR1 (OsCPPR1) contributes to pollen development and localizes to the cytoplasm. Knocking down OsCPPR1 led to abnormal plastid development in tapetal cells, prolonged tapetal programmed cell death (PCD) and tapetum degradation, and significantly reduced pollen fertility. Transcriptome analysis revealed that the transcript level of OsGOLDEN-LIKE1 (OsGLK1), which encodes a transcription factor that regulates plastid development and maintenance, was significantly higher in the OsCPPR1 knockdown plants compared to wild-type plants. We further determined that OsCPPR1 downregulates OsGLK1 transcription by directly binding to the single-stranded regions of OsGLK1 mRNAs. Overexpression of OsGLK1 resulted in abnormal tapetum and plastid development, similar to that seen in OsCPPR1 knockdown plants, and suppression of OsGLK1 partially restored pollen fertility in the OsCPPR1 knockdown plants. We therefore conclude that OsCPPR1 suppresses OsGLK1 in the regulation of plastid development and PCD in the tapetum. Our work revealed novel functions for a cytosolic PPR, demonstrating the diverse roles of PPRs in plants and identifying a new regulatory mechanism for regulating pollen development in rice.
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Oryza , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plastídeos/genética , Plastídeos/metabolismo , PólenRESUMO
BACKGROUND: We aim to create a holistic competency-based assessment system to measure competency evolution over time - one of the first such systems in China. METHOD: Two rounds of self-reported surveys were fielded among the graduates from the Shantou University Medical College: June through December 2017, and May through August 2018. Responses from three cohorts of graduates specializing in clinical medicine - new graduates, resident physicians, and senior physicians - were analyzed. Gaps between respondents' expected and existing levels of competencies were examined using a modified service quality model, SERVQUAL. RESULTS: A total of 605 questionnaires were collected in 2017 for the construction of competency indicators and a 5-level proficiency rating scale, and 407 in 2018, for confirmatory factor and competency gap analysis. Reliability coefficients of all competency indicators (36) were greater than 0.9. Three competency domains were identified through exploratory factor analysis: knowledge (K), skills (S), and attitude (A). The confirmatory factor analysis confirmed the fit of the scale (CMIN/DF < 4; CFI > 0.9; IFI > 0.9; RMSEA ≤ 0.08). Within the cohorts of resident and senior physicians, the largest competency gap was seen in the domain of knowledge (K): -1.84 and -1.41, respectively. Among new graduates, the largest gap was found in the domain of skills (S) (-1.92), with the gap in knowledge (-1.91) trailing closely behind. CONCLUSIONS: A competency-based assessment system is proposed to evaluate clinician's competency development in three domains: knowledge (K), skills (S), and attitude (A). The system consists of 36 competency indicators, a rating scale of 5 proficiency levels, and a gap analysis to measure competency evolution through 3 key milestones in clinician's professional career: new graduate, resident physician, and senior physician. The competency gaps identified can provide evidence-based guide to clinicians' own continuous development as well as future medical curriculum improvements.
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Competência Clínica , Médicos , China , Humanos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
BACKGROUND: To validate a competency-based assessment scale for students majoring in clinical medicine, ASK-SEAT. Students' competency growth across grade years was also examined for trends and gaps. METHODS: Questionnaires were distributed online from May through August in 2018 to Year-2 to Year-6 students who majored in clinical medicine at the Shantou University Medical College (China). Cronbach alpha values were calculated for reliability of the scale, and exploratory factor analysis employed for structural validity. Predictive validity was explored by correlating Year-4 students' self-assessed competency ratings with their licensing examination scores (based on Kendall's tau-b values). All students' competency development over time was examined using the Mann-Whitney U test. RESULTS: A total of 760 questionnaires meeting the inclusion criteria were analyzed. The overall Cronbach's alpha value was 0.964, and the item-total correlations were all greater than 0.520. The overall KMO measure was 0.966 and the KMO measure for each item was greater than 0.930 (P < 0.001). The eigenvalues of the top 3 components extracted were all greater than 1, explaining 55.351, 7.382, and 5.316% of data variance respectively, and 68.048% cumulatively. These components were aligned with the competency dimensions of skills (S), knowledge (K), and attitude (A). Significant and positive correlations (0.135 < Kendall's tau-b < 0.276, p < 0.05) were found between Year-4 students' self-rated competency levels and their scores for the licensing examination. Steady competency growth was associated with almost all indicators, with the most pronounced growth in the domain of skills. A lack of steady growth was seen in the indicators of "applying the English language" and "conducting scientific research & innovating". CONCLUSIONS: The ASK-SEAT, a competency-based assessment scale developed to measure medical students' competency development shows good reliability and structural validity. For predictive validity, weak-to-moderate correlations are found between Year-4 students' self-assessment and their performance at the national licensing examination (Year-4 students start their clinical clerkship during the 2nd semester of their 4th year of study). Year-2 to Year-6 students demonstrate steady improvement in the great majority of clinical competency indicators, except in the indicators of "applying the English language" and "conducting scientific research & innovating".
Assuntos
Estágio Clínico , Medicina Clínica , Estudantes de Medicina , Competência Clínica , Avaliação Educacional , Humanos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Parotid tumours (PTs) have a variety of pathological types, and the surgical procedures differ depending on the tumour type. However, accurate diagnosis of PTs from the current preoperative examinations is unsatisfactory. METHODS: This retrospective study was approved by the Ethics Committee of our hospital, and the requirement for informed consent was waived. A total of 73 patients with PTs, including 55 benign and 18 malignant tumours confirmed by surgical pathology, were enrolled. All patients underwent diffusion-weighted imaging (DWI), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), susceptibility-weighted imaging (SWI), T2-weighted imaging (T2WI), and T1-weighted imaging (T1WI). The signal uniformity and capsule on T2WI, apparent diffusion coefficient (ADC) derived from DWI, semi-quantitative parameter time-intensity curve (TIC) pattern, and quantitative parameters including transfer constant (Ktrans), extravascular extracellular volume fraction (Ve), wash-out constant (Kep) calculated from DCE-MRI, and intratumoural susceptibility signal (ITSS) obtained from SWI were assessed and compared between benign and malignant PTs. Logistic regression analysis was used to select the predictive parameters for the classification of benign and malignant parotid gland tumours, and receiver operating characteristic (ROC) curve analysis was used to evaluate their diagnostic performance. RESULTS: Malignant PTs tended to exhibit a type C TIC pattern, whereas benign tumours tended to be type A and B (p < 0.001). Benign PTs had less ITSS than malignant tumours (p < 0.001). Multivariate analyses showed that ADC, Ve, and ITSS were predictors of tumour classification. ROC analysis showed that the area under the curve (AUC) of ADC, Ve, ITSS, and ADC combined with Ve were 0.623, 0.615, 0.826, and 0.782, respectively, in differentiating between malignant and benign PTs. When ITSS was added, the AUCs of ADC, Ve, and ADC combined with Ve increased to 0.882, 0.848, and 0.930, respectively. CONCLUSION: SWI offers incremental diagnostic value to DWI and DCE-MRI in the characterisation of parotid gland tumours.
Assuntos
Neoplasias Parotídeas , Meios de Contraste , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Glândula Parótida , Neoplasias Parotídeas/diagnóstico por imagem , Curva ROC , Estudos RetrospectivosRESUMO
PURPOSE: To investigate the effects of quercetin on ovulation disorder and expression of androgen receptor (AR) and C-type natriuretic peptide (CNP) / Natriuretic Peptide Receptor 2 (NPR2) in dehydroepiandrosterone (DHEA)-induced polycystic ovary syndrome (PCOS) rat model. METHODS: DHEA was used to construct the PCOS rat model. After intervention with quercetin, metformin, and AR, the estrous cycle, ovarian and uterine weight of rats were measured. The morphological changes of ovarian and uterine were detected by hematoxylin-eosin staining (HE staining). Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured by Enzyme linked immunosorbent assay (ELISA). Immunohistochemical detection of interleukin-6 (IL-6), interleukin-1ß (IL-1ß), tumor necrosis factor-alpha (TNF-α), B-cell lymphoma-2 (BCL-2), BCL2-Associated X (Bax) and AR expression in ovarian. Determination of the expression of CNP and NPR2 mRNA by qRT-PCR. Chromatin immunocoprecipitation (ChIP) was used to detect the ability of AR to bind to CNP or NPR2 promoter. RESULTS: The results showed that quercetin could significantly reduce the expression of Testosterone (T) , Estradiol (E2) , LH, Bax, IL-1ß, IL-6 and TNF-α, increase the expression of FSH and Bcl-2, inhibit the expression of AR, regulate the expression of CNP / NPR2 gene and protein by affecting the combination of AR with the specific sequence of CNP and NPR2 gene promoters, restore the maturation of oocyte and ovulation. CONCLUSION: The results suggest that quercetin can alleviate the hormone, metabolic and ovulatory aberrations caused by PCOS, and provide experimental basis for the clinical application of quercetin in PCOS.