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Background: A considerable proportion of hypertensive patients may experience lacunar infarction. Therefore, early identification of the risk for lacunar infarction in hypertensive patients is particularly important. This study aimed to develop and validate a concise nomogram for predicting lacunar infarction in hypertensive patients. Methods: Retrospectively analyzed the clinical data of 314 patients with accurate history of hypertension in the Second Affiliated Hospital of Wannan Medical College from January 2021 to December 2022. All the patients were randomly assigned to the training set (n=220) and the validation set (n=94) with 7:3. The diagnosis of lacunar infarction in patients was confirmed using cranial CT or MRI. The independent risk factors of lacunar infarction were determined by Least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression analysis. The nomogram was built based on the independent risk factors. The nomogram's discrimination, calibration, and clinical usefulness were evaluated by receiver operating characteristics (ROC) curve, calibration curve, and decision curve analysis (DCA) analysis, respectively. Results: The incidence of lacunar infarction was 34.50% and 33.00% in the training and validation sets, respectively. Five independent predictors were made up of the nomogram, including age (OR=1.142, 95% CI: 1.089-1.198, P<0.001), diabetes mellitus (OR=3.058, 95% CI: 1.396-6.697, P=0.005), atrial fibrillation (OR=3.103, 95% CI: 1.328-7.250, P=0.009), duration of hypertension (OR=1.130, 95% CI: 1.045-1.222, P=0.002), and low-density lipoprotein (OR=2.147, 95% CI: 1.250-3.688, P=0.006). The discrimination with area under the curve (AUC) was 0.847 (95% CI: 0.789-0.905) in the training set and was a slight increase to 0.907 (95% CI: 0.838-0.976) in the validation set. The calibration curve showed high coherence between the predicted and actual probability of lacunar infarction. Moreover, the DCA analysis indicated that the nomogram had a higher overall net benefit of the threshold probability range in both two sets. Conclusion: Age, diabetes mellitus, atrial fibrillation, duration of hypertension, and low-density lipoprotein were significant predictors of lacunar infarction in hypertensive patients. The nomogram based on the clinical data was constructed, which was a useful visualized tool for clinicians to assess the risk of the lacunar infarction in hypertensive patients.
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The differential responses of methanogenesis and methanotrophy to elevated carbon dioxide concentrations ([CO2]) (e[CO2]) and elevated temperature ([T]) (e[T]) may lead to dramatic changes in the response of CH4 emissions from rice paddies to global warming. In this study, we systematically investigated the responses and mechanisms of CH4 flux from rice paddies to e[CO2] and e[T] based on the production and oxidation of CH4. The CH4 flux, soil properties, and soil methanogenesis and methanotrophy were observed under CK (ambient [CO2]â¯+â¯ambient [T]), EC (e[CO2] by 200⯵molâ¯mol-1â¯+â¯ambient [T]), ET (ambient [CO2]â¯+â¯e[T] by 2⯰C), and ECT (e[CO2] by 200⯵molâ¯mol-1â¯+â¯e[T] by 2⯰C) treatments. The results revealed that EC, ET, and ECT significantly increased the cumulative amount of CH4 (CAC) in the rice paddies by 10.63, 15.20, and 11.77â¯kgâ¯ha-1, respectively, compared with CK. ECT increased the CAC in the rice paddies by 1.14â¯kgâ¯ha-1 compared with EC. Moreover, EC, ET, and ECT significantly enhanced the methane production potential (MPP) and methane oxidation potential (MOP) and tended to increase the mcrA gene abundance of the methanogens. EC tended to prompt the pmoA gene abundance of the methanotrophs, but the effect of ET on the pmoA gene abundance was less consistent across the growth stages. ECT significantly decreased the relative abundances of Methanosarcina and Methylocystis (Type II) by 4.9â¯% and 14.2â¯%, respectively, while it increased the relative abundance of Methylosarcina (Type I) by 24.0â¯% compared with CK. Overall, the increased MPP/MOP, mcrA/pmoA, and microbial biomass carbon under climate change increased the CH4 flux from the rice paddies. The contribution of e[CO2] to the CH4 flux was significantly enhanced by e[T], which could further exacerbate the risk of global climate change induced by e[CO2].
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Water transportation to developing tissues relies on the structure and function of plant xylem cells. Plant microtubules govern the direction of cellulose microfibrils and guide secondary cell wall formation and morphogenesis. However, the relevance of microtubule-determined xylem wall thickening patterns in plant hydraulic conductivity remains unclear. In the present study, we identified a maize (Zea mays) semi-dominant mutant, designated drought-overly-sensitive1 (ZmDos1), the upper leaves of which wilted even when exposed to well-watered conditions during growth; the wilting phenotype was aggravated by increased temperatures and decreased humidity. Protoxylem vessels in the stem and leaves of the mutant showed altered thickening patterns of the secondary cell wall (from annular to spiral), decreased inner diameters, and limited water transport efficiency. The causal mutation for this phenotype was found to be a G-to-A mutation in the maize gene α-tubulin4, resulting in a single amino acid substitution at position 196 (E196K). Ectopic expression of the mutant α-tubulin4 in Arabidopsis (Arabidopsis thaliana) changed the orientation of microtubule arrays, suggesting a determinant role of this gene in microtubule assembly and secondary cell wall thickening. Our findings suggest that the spiral wall thickenings triggered by the α-tubulin mutation are stretched during organ elongation, causing a smaller inner diameter of the protoxylem vessels and affecting water transport in maize. This study underscores the importance of tubulin-mediated protoxylem wall thickening in regulating plant hydraulics, improves our understanding of the relationships between protoxylem structural features and functions, and offers candidate genes for the genetic enhancement of maize.
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Endocytic recycling is an intracellular trafficking pathway that returns endocytosed molecules to the plasma membrane (PM) via the recycling endosome. This pathway plays a crucial role in remodeling PM composition and is thus essential for normal cellular homeostasis. In plants, endocytic recycling regulates the localization and abundance of receptors, transporters, and channels at the PM that are involved in many aspects of plant growth and development. Despite its importance, the recycling endosome and the underlying sorting mechanisms for cargo recycling in plants remain understudied in comparison to the endocytic recycling pathways of animal systems. In this review, we focus on the cumulative evidence suggesting the existence of endosomes decorated by regulators that contribute to recycling in plant cells. We summarize the chemical inhibitors used for analyzing cargo recycling and discuss recent advances in our understanding of how endocytic recycling participates in various plant cellular and physiological events.
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Soil drought and salinization, caused by water deficiency, have become the greatest concerns limiting crop production. Up to now, the WRKY transcription factor and histone deacetylase have been shown to be involved in drought and salt responses. However, the molecular mechanism underlying their interaction remains unclear in cotton. Herein, we identified GhWRKY4, a member of WRKY gene family, which is induced by drought and salt stress and is located in the nucleus. The ectopic expression of GhWRKY4 in Arabidopsis enhanced drought and salt tolerance, and suppressing GhWRKY4 in cotton increased susceptibility to drought and salinity. Subsequently, DAP-seq analysis revealed that the W box element in the promoter of stress-induced genes could potentially be the binding target for GhWRKY4 protein. GhWRKY4 binds to the promoters of GhHDA8 and GhNHX7 via W box element, and the expression level of GhHDA8 was increased in GhWRKY4-silenced plants. In addition, GhHDA8-overexpressed Arabidopsis were found to be hypersensitive to drought and salt stress, while silencing of GhHDA8 enhanced drought and salt tolerance in cotton. The stress-related genes, such as GhDREB2A, GhRD22, GhP5CS, and GhNHX7, were induced in GhHDA8-silenced plants. Our findings indicate that the GhWRKY4-GhHDA8 module regulates drought and salt tolerance in cotton. Collectively, the results provide new insights into the coordination of transcription factors and histone deacetylases in regulating drought and salt stress responses in plants.
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Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Gossypium/metabolismo , Tolerancia a la Sal/genética , Sequías , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Plantas Modificadas Genéticamente/genética , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Background: Limited studies have observed the prognostic value of CT images for esophageal neuroendocrine carcinoma (NEC) due to rare incidence and low treatment experience in clinical. In this study, the pretreatment enhanced CT texture features and clinical characteristics were investigated to predict the overall survival of esophageal NEC. Methods: This retrospective study included 89 patients with esophageal NEC. The training and testing cohorts comprised 61 (70%) and 28 (30%) patients, respectively. A total of 402 radiomics features were extracted from the tumor region that segmented pretreatment venous phase CT images. The least absolute shrinkage and selection operator (LASSO) Cox regression was applied to feature dimension reduction, feature selection, and radiomics signature construction. A radiomics nomogram was constructed based on the radiomics signature and clinical risk factors using a multivariable Cox proportional regression. The performance of the nomogram for the pretreatment prediction of overall survival (OS) was evaluated for discrimination and calibration. Results: Only the enhancement degree was an independent factor in clinical variable influenced OS. The radiomics signatures demonstrated good predictability for prognostic status discrimination. The radiomics nomogram integrating texture signatures was slightly superior to the nomogram derived from the combined model with a C-index of 0.844 (95%CI: 0.783-0.905) and 0.847 (95% CI: 0.782-0.912) in the training set, and 0.805 (95%CI: 0.707-0.903) and 0.745 (95% CI: 0.639-0.851) in the testing set, respectively. Conclusion: The radiomics nomogram based on pretreatment CT radiomics signature had better prognostic power and predictability of the overall survival in patients with esophageal NEC than the model using combined variables.
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The unique dumbbell-shape of grass guard cells (GCs) is controlled by their cell walls which enable their rapid responses to the environment. The molecular mechanisms regulating the synthesis and assembly of GC walls are as yet unknown. Here we have identified BZU3, a maize gene encoding UDP-glucose 4-epimerase that regulates the supply of UDP-glucose during GC wall synthesis. The BZU3 mutation leads to significant decreases in cellular UDP-glucose levels. Immunofluorescence intensities reporting levels of cellulose and mixed-linkage glucans are reduced in the GCs, resulting in impaired local wall thickening. BZU3 also catalyzes the epimerization of UDP-N-acetylgalactosamine to UDP-N-acetylglucosamine, and the BZU3 mutation affects N-glycosylation of proteins that may be involved in cell wall synthesis and signaling. Our results suggest that the spatiotemporal modulation of BZU3 plays a dual role in controlling cell wall synthesis and glycosylation via controlling UDP-glucose/N-acetylglucosamine homeostasis during stomatal morphogenesis. These findings provide insights into the mechanisms controlling formation of the unique morphology of grass stomata.
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Racemasas y Epimerasas , Zea mays , Zea mays/genética , Zea mays/metabolismo , Racemasas y Epimerasas/metabolismo , Glicosilación , Acetilglucosamina/metabolismo , Poaceae/metabolismo , Pared Celular/metabolismo , Uridina Difosfato/metabolismoRESUMEN
Shipping companies' implementation of sustainable shipping management is an important means of protecting major water bodies in the marine environment. This research establishes a theoretical model based on institutional theory and incorporates a micro-consciousness level to explore the factors influencing companies' implementation of sustainable shipping practices. After surveying the management of Chinese shipping companies, a total of 282 datasets were obtained for analysis. This study demonstrated that rules and regulations, societal norms, environmental awareness, and legal awareness can improve shipping companies' sustainable shipping practices. Meanwhile, these practices have a positive impact on the environmental, financial, and competitive performance of shipping companies. Moreover, these findings are highly significant for maritime environmental protection and sustainability.
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Conservación de los Recursos Naturales , Corporaciones Profesionales , Navíos , Desarrollo Sostenible , Transportes , Modelos Teóricos , Industrias , Transportes/métodos , Conservación de los Recursos Hídricos , ChinaRESUMEN
OBJECTIVES: This study aimed to screen the potential risk factors for academic burnout among adolescents during the COVID-19 pandemic, develop and validate a predictive tool based on the risk factors for predicting academic burnout. DESIGN: This article presents a cross-sectional study. SETTING: This study surveyed two high schools in Anhui Province, China. PARTICIPANTS: A total of 1472 adolescents were enrolled in this study. OUTCOME MEASURES: The questionnaires included demographic characteristic variables, living and learning states and adolescents' academic burnout scale. Least absolute shrinkage and selection operator and multivariate logistic regression analyses were employed to screen the risk factors for academic burnout and develop a predictive model. The receiver operating characteristic (ROC) curve and decision curve analysis (DCA) were used to assess the accuracy and discrimination of the nomogram. RESULTS: In this study, 21.70% of adolescents reported academic burnout. Multivariable logistic regression analysis showed that single-child family (OR=1.742, 95% CI: 1.243 to 2.441, p=0.001), domestic violence (OR=1.694, 95% CI: 1.159 to 2.476, p=0.007), online entertainment (>8 hours/day, OR=3.058, 95% CI: 1.634 to 5.720, p<0.001), physical activity (<3 hours/week, OR=1.686, 95% CI: 1.032 to 2.754, p=0.037), sleep duration (<6 hours/night, OR=2.342, 95% CI: 1.315 to 4.170, p=0.004) and academic performance (<400 score, OR=2.180, 95% CI: 1.201 to 3.958, p=0.010) were independent significant risk factors associated with academic burnout. The area under the curve of ROC with the nomogram was 0.686 in the training set and 0.706 in the validation set. Furthermore, DCA demonstrated that the nomogram had good clinical utility for both sets. CONCLUSIONS: The developed nomogram was a useful predictive model for academic burnout among adolescents during the COVID-19 pandemic. It is essential to emphasise the importance of mental health and promote a healthy lifestyle among adolescents during the future pandemic.
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Agotamiento Psicológico , COVID-19 , Pueblos del Este de Asia , Nomogramas , Estudiantes , Adolescente , Humanos , Agotamiento Psicológico/epidemiología , COVID-19/epidemiología , COVID-19/psicología , Estudios Transversales , Pueblos del Este de Asia/psicología , Pueblos del Este de Asia/estadística & datos numéricos , Pandemias , Estudiantes/psicología , Factores de Riesgo , Medición de RiesgoRESUMEN
Background: Post-stroke cognitive impairment (PSCI) after lacunar infarction was worth attention in recent years. An easy-to-use score model to predict the risk of PSCI was rare. This study aimed to explore the association between serum amyloid A (SAA) and cognitive impairment, and it also developed a nomogram for predicting the risk of PSCI in lacunar infarction patients. Methods: A total of 313 patients with lacunar infarction were enrolled in this retrospective study between January 2021 and December 2021. They were divided into a training set and a validation set at 70%:30% randomly. The Chinese version of the Mini-Mental State Examination (MMSE) was performed to identify cognitive impairment 3 months after discharge. Univariate and multivariate logistic regression analyses were used to determine the independent risk factors for PSCI in the training set. A nomogram was developed based on the five variables, and the calibration curve and the receiver operating characteristic (ROC) curve were drawn to assess the predictive ability of the nomogram between the training set and the validation set. The decision curve analysis (DCA) was also conducted in both sets. Results: In total, 52/313 (16.61%) participants were identified with PSCI. The SAA levels in patients with PSCI were significantly higher than non-PSCI patients in the training set (P < 0.001). After multivariate analysis, age, diabetes mellitus, white blood count, cystatin C, and SAA were independent risk predictors of PSCI. The nomogram demonstrated a good discrimination performance between the training set (AUC = 0.860) and the validation set (AUC = 0.811). The DCA showed that the nomogram had a well clinical utility in the two sets. Conclusion: The increased SAA is associated with PSCI in lacunar infarction patients, and the nomogram developed with SAA can increase prognostic information for the early detection of PSCI.
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Being sessile in soil, plant cells rely on cell-surface receptors to sense and transduce environmental stimulus signals into intracellular responses. FERONIA (FER), a Catharanthus roseus receptor-like kinase 1-like protein, has emerged as a versatile regulator of plant growth, development, and stress responses. In recent years, accumulating studies have witnessed rapid advances in dissecting the mechanisms underlying the interaction between FER and its partners in response to pathogen invasion, particularly regulation of immune complex formation and signalling. Moreover, hormonal signalling, rhizosphere microbiota and other constituents are also extensively involved in these processes.
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Proteínas de Arabidopsis , Complejo Antígeno-Anticuerpo , Proteínas de Arabidopsis/metabolismo , Fosfotransferasas/metabolismo , Transducción de Señal , SueloRESUMEN
Insulin, a principal anabolic hormone produced by pancreatic ß-cells, has a primary function of storage of nutrients following excessive energy intake. Pre- or early type 2 diabetes stages present hyperinsulinemia (ß-cell dysfunction) and insulin resistance. Initiation of hyperinsulinemia is triggered by a loss of first-phase glucose-stimulated insulin secretion with altered membrane ion channel distribution. More factors, including insulin resistance and excessive proliferation of ß-cells, deteriorate the hyperinsulinemia, whereas the hyperinsulinemia contributes to further development of insulin resistance and type 2 diabetes; to develop eventually late-stage diabetes with absolute insulin deficiency. In this mini-review, the major focus was put on the causes and pathophysiology of hyperinsulinemia, and the metabolic consequences and current treatment of hyperinsulinemia were discussed. The data used in this narrative review were collected mainly from relevant discoveries in the past 3 years.
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Diabetes Mellitus Tipo 2 , Hiperinsulinismo , Resistencia a la Insulina , Glucosa/metabolismo , Homeostasis , Humanos , Insulina/metabolismo , Resistencia a la Insulina/fisiologíaRESUMEN
BACKGROUND: Gastric glomus tumor (GGT) is a rare neoplasm that is difficult to distinguish from other gastric submucosal tumors due to a lack of diagnostic experience. The goal of this study was to better understand GGT by looking at its clinicopathological features, computed tomography (CT) features, and differential diagnosis. METHODS: The clinical data and CT findings of 21 pathologically confirmed GGT patients were examined. The clinical characteristics and CT findings of benign GGT were compared to gastric stromal tumors (GST) (n = 30) and heterotopic pancreas (n = 30). RESULTS: The 21 cases included six males and fifteen females ranging in age from 42 to 64 years. The lesions were found in the gastric body in four cases and the antrum in seventeen. GGT was diagnosed as benign in 20 cases and malignant in one. In benign cases, the glomus cells were small, uniform, showed perivascular hemangiopericytomalike or solid nestlike structures. Obvious mitotic figures were observed in the malignant case. SMA staining was positive in the tumor cells. A quasi-round or round solid mass protruded into the gastric cavity in 20 benign cases, with a clear and smooth edge. The long to short diameter ratio was 1.01 ± 0.15. All of the benign cases had obvious enhancement, with homogeneous enhancement in ten cases and heterogeneous enhancement in ten cases, as well as central filling enhancement in 12 cases. The ratio of CT value of lesion to abdominal aorta in arterial phase and venous phase were (0.41 ± 0.11) and (0.81 ± 0.20), which were significantly higher than GST and heterotopic pancreas. The irregular mass broke through the gastric wall and invaded liver with poorly defined boundary and internal necrosis, heterogeneous persistent moderate enhancement with thickening blood supply arteries was seen in one malignant case with a long diameter of 150 mm and a thick diameter of 30 mm. CONCLUSIONS: CT enhancement usually shows persistent obvious enhancement, especially in arterial phase, which provides important value for the diagnosis. CT findings can help in the differential diagnosis of GGT and other submucosal tumors.
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Tumor Glómico , Neoplasias Gástricas , Adulto , Diagnóstico Diferencial , Femenino , Tumor Glómico/diagnóstico por imagen , Tumor Glómico/patología , Humanos , Masculino , Persona de Mediana Edad , Páncreas/diagnóstico por imagen , Páncreas/patología , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/patología , Tomografía Computarizada por Rayos X/métodosRESUMEN
The plant receptor-like kinase FERONIA (FER) functions in the response to multiple extracellular signals, thereby regulating diverse cellular processes, such as polarized cell growth, hormone signaling and responses to pathogens. Here, we reported that in Arabidopsis thaliana, flagellin peptide flg22 stimulus significantly promoted the lateral mobility and dissociation of FER from the plasma membrane by inducing the association of FER with membrane microdomain components. FER underwent constitutive endocytosis and recycling in a brefeldin A (BFA)-sensitive manner via a clathrin-mediated pathway. Following flg22 elicitation, FER localized to bona fide endosomes via two distinct endocytic routes, showing differential sensitivity to BFA. These results at the single-particle level confirm that FER acts as an essential regulator during flg22 perception and immune activation, thus broadening our understanding of location-specific protein dynamics and membrane trafficking in receptor/receptor kinase signaling.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Brefeldino A/farmacología , Endocitosis , Flagelina/metabolismo , Flagelina/farmacología , Fosfotransferasas/metabolismoRESUMEN
Our current research aims to evaluate the efficiency of a flavor enhancer, maltol (produced by heating ginseng) against cisplatin-evoked cardiotoxicity by establishing cisplatin-induced heart injury in vivo and H9C2 rat cardiomyocyte model. The cisplatin-treated mice at 3 mg/kg for four times on the 7th, 9th, 11th and 13th day, and in them appeared a serious cardiac damage accompanied with the increase in indicators of heart damage. Multiple exposure of 3 mg/kg for four times of cisplatin increased cardiac cells apoptosis with increased expression of Bax and cleaved-caspase 3, and decreased expression of Bcl-2. Interestingly, supplement of maltol at doses of 50 and 100 mg/kg for 15 days significantly suppressed the cardiac disturbance. In cultured H9C2 cells, maltol enhanced PI3K/Akt expression level during cisplatin treatment, and reduced cisplatin-induced apoptosis. Notably, inhibition of PI3K/Akt by LY294002 and HY-10249A lessened the efficacy of maltol. In mice, maltol apparently induced PI3K/Akt in heart tissues and protected against cisplatin-induced cardiotoxicity. In conclusion, maltol exerted the protective effects against cisplatin-induced cardiotoxicity, at least partially by inhibiting the activation of PI3K/Akt signaling pathways in cardiomyocytes, to ease oxidative stress, and alleviate reactive oxygen species-mediated apoptosis.
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Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Animales , Apoptosis , Cardiotoxicidad/tratamiento farmacológico , Cisplatino/efectos adversos , Ratones , Miocitos Cardíacos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Pironas , Ratas , Roedores/metabolismo , Transducción de SeñalRESUMEN
PURPOSE: To investigate the diagnostic performance of CT signs for detecting bowel ischemia and necrosis in adhesive small bowel obstruction(SBO) with subjective and objective methods. MATERIALS AND METHODS: 113 adhesive SBO patients were enrolled and divided into ischemic group (49 cases in necrotic group and 35 cases in reversible ischemic group) and non-ischemic group (29 cases) according to the operation results. Subjective visual assessment of CT signs associated with ischemia and necrosis was performed by two radiologists independently. Elevated unenhanced attenuation and enhancement value of involved bowel wall were objectively measured and compared by single factor analysis of variance. Cut-off value and diagnostic performance were evaluated by receiver operating characteristic curve (ROC). RESULTS: Closed-loop mechanism, reduced bowel wall enhancement, and mesenteric edema were associated with bowel ischemia, with sensitivity of 81.0%, 65.5%, 75.0%, and specificity of 86.2%, 96.6%, 89.7%, respectively. Increased unenhanced bowel wall attenuation was a specific sign for necrosis with 100.0% specificity and 51.0% sensitivity. The sensitivity and specificity for ischemia were 86.0% and 91.9% with cut-off enhancement value lower than 33.5 HU. The sensitivity and specificity for necrosis were 58.2% and 100.0% with cut-off elevated unenhanced attenuation higher than 16.5 HU, 86.7% and 83.3% with cut-off enhancement value lower than 21.5 HU. CONCLUSION: Reduced bowel wall enhancement and increased unenhanced bowel wall attenuation were good indicators of bowel ischemia and necrosis. The objective measurement of elevated unenhanced attenuation and enhancement value can predict bowel ischemia and necrosis more accurately.
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Adhesivos , Obstrucción Intestinal , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Necrosis/diagnóstico por imagen , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos XRESUMEN
Membrane proteins have key functions in signal transduction, transport, and metabolism. Therefore, deciphering the interactions between membrane proteins provides crucial information on signal transduction and the spatiotemporal organization of protein complexes. However, detecting the interactions and behaviors of membrane proteins in their native environments remains difficult. Förster resonance energy transfer (FRET) is a powerful tool for quantifying the dynamic interactions and assembly of membrane proteins without disrupting their local environment, supplying nanometer-scale spatial information and nanosecond-scale temporal information. In this review, we briefly introduce the basic principles of FRET and assess the current state of progress in the development of new FRET techniques (such as FRET-FLIM, homo-FRET, and smFRET) for the analysis of plant membrane proteins. We also describe the various FRET-based biosensors used to quantify the homeostasis of signaling molecules and the active state of kinases. Furthermore, we summarize recent applications of these advanced FRET sensors in probing membrane protein interactions, stoichiometry, and protein clustering, which have shed light on the complex biological functions of membrane proteins in living plant cells.
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Transferencia Resonante de Energía de Fluorescencia , Proteínas de la Membrana , Fenómenos Biofísicos , Homeostasis , Proteínas de la Membrana/genética , Transducción de SeñalRESUMEN
During the COVID-19 pandemic, livestream shopping has provided consumers with a way to maintain social distancing while offering an alternative to offline shopping. This study aims to understand the impact of COVID-19 and other public health crises on the behavioral intentions of consumers using livestream shopping technology. A theoretical model was designed that combines the health belief model, trust theory, and the theory of planned behavior. Empirical data were collected from 358 residents in China and then analyzed using structural equation modeling. The results showed that perceived susceptibility, perceived severity, perceived benefits, and perceived obstacles had a significant impact on consumer trust. Consumer trust in turn had a direct impact on behavioral intention and an indirect impact on behavioral intention via attitude. These research results have practical implications for livestream shopping merchants, platform decision-makers, and service designers.
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COVID-19 , Pandemias , Comportamiento del Consumidor , Humanos , Distanciamiento Físico , SARS-CoV-2 , TecnologíaRESUMEN
The plant hormone auxin controls many aspects of plant development. Membrane trafficking processes, such as secretion, endocytosis and recycling, regulate the polar localization of auxin transporters in order to establish an auxin concentration gradient. Here, we investigate the function of the Arabidopsis thaliana R-SNAREs VESICLE-ASSOCIATED MEMBRANE PROTEIN 721 (VAMP721) and VAMP722 in the post-Golgi trafficking required for proper auxin distribution and seedling growth. We show that multiple growth phenotypes, such as cotyledon development, vein patterning and lateral root growth, were defective in the double homozygous vamp721 vamp722 mutant. Abnormal auxin distribution and root patterning were also observed in the mutant seedlings. Fluorescence imaging revealed that three auxin transporters, PIN-FORMED 1 (PIN1), PIN2 and AUXIN RESISTANT 1 (AUX1), aberrantly accumulate within the cytoplasm of the double mutant, impairing the polar localization at the plasma membrane (PM). Analysis of intracellular trafficking demonstrated the involvement of VAMP721 and VAMP722 in the endocytosis of FM4-64 and the secretion and recycling of the PIN2 transporter protein to the PM, but not its trafficking to the vacuole. Furthermore, vamp721 vamp722 mutant roots display enlarged trans-Golgi network (TGN) structures, as indicated by the subcellular localization of a variety of marker proteins and the ultrastructure observed using transmission electron microscopy. Thus, our results suggest that the R-SNAREs VAMP721 and VAMP722 mediate the post-Golgi trafficking of auxin transporters to the PM from the TGN subdomains, substantially contributing to plant growth.