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1.
PLoS One ; 19(7): e0306919, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38995939

RESUMEN

The rapid development of B2B has brought about fierce competition among suppliers, and how to gain customer attention and improve performance has become a common concern in academia and industry. This study examined the drivers and mechanisms of B2B performance from an enterprise capability perspective. We collected transaction and enterprise data from 325 suppliers on Alibaba 1688 platform and constructed a structural equation model (SEM). Results showed that supplier service capability, logistics capability, and production capacity all positively impacted B2B performance through the mediating role of customer attention. In addition, we found that service and logistics capabilities are more critical for attracting customer attention for Original Equipment Manufacturer (OEM) suppliers than for non-OEM suppliers. The findings contribute to understanding B2B commerce and provide constructive directions for B2B suppliers to improve their performance.


Asunto(s)
Comercio , Humanos , Comportamiento del Consumidor
2.
Environ Pollut ; 357: 124467, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38950850

RESUMEN

The 31st FISU Summer World University Games (SWUG) was held in Chengdu, southwestern China, from July 22 to August 8, 2023. A series of control measures were carried out to ensure good air quality during the SWUG, providing an opportunity to investigate the atmospheric behaviors of light-absorbing aerosols under such a substantial disturbance caused by the control measures. To assess the impacts of emission controls on primary pollutants, a field campaign was conducted at a rural site in Chengdu to investigate the characterization of equivalent black carbon (eBC). The changes of eBC concentrations before, during, and after the SWUG were characterized. The sources of eBC were resolved, and the impacts of atmospheric processes on the absorption capacity were also investigated. During the SWUG, the eBC concentration decreased by 12.1 % and 25.3 % compared with those before and after the SWUG. A fossil fuel combustion (eBCff) and a biomass burning (eBCbb) originated eBC were resolved using the aethalometer model. Both eBCff and eBCbb decreased during the SWUG, indicating the effectiveness of control measures. After the SWUG, the influence of biomass burning emissions became more and more significant, and the contribution of brown carbon (BrC) to light absorption at 370-660 nm increased by 52, 19, 7, 6, and 17 % compared to those during the SWUG. As the biomass burning emitted aerosols aged, the absorption Ångström exponent and babs(BrC370nm) decreased gradually, which was mainly due to the photobleaching of the chromophores during the daytime. eBCff was mainly affected by strong wind, while high eBCbb concentration was mainly attributed to the gradual accumulation of biomass-burning emissions near the observation site. The results show the significant reduction of eBC with the implementation of the air pollution mitigation campaign, and provide insights on the impacts of atmospheric processes on BC optical properties during summertime.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Estaciones del Año , Hollín , China , Contaminantes Atmosféricos/análisis , Hollín/análisis , Monitoreo del Ambiente/métodos , Aerosoles/análisis , Carbono/análisis , Universidades , Contaminación del Aire/estadística & datos numéricos , Material Particulado/análisis
3.
Sci Total Environ ; 944: 173712, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-38830412

RESUMEN

The sensitivity of tropospheric ozone (O3) to its precursors volatile organic compounds (VOCs) and nitrogen oxides (NOX) determines the emission reduction strategy for O3 mitigation. Due to the lack of comprehensive vertical measurements of VOCs, the vertical distribution of O3 sensitivity regimes has not been well understood. O3 precursor sensitivity determined by ground-level measurements has been generally used to guide O3 control strategy. Here, to precisely diagnose O3 sensitivity regimes at different heights in the planetary boundary layer (PBL), we developed a vertical measurement system based on an unmanned aerial vehicle platform to conduct comprehensive vertical measurements of VOCs, NOX and other relevant parameters. Our results suggest that the O3 precursor sensitivity shifts from a VOC-limited regime at the ground to a NOX-limited regime at upper layers, indicating that the ground-level O3 sensitivity cannot represent the situation of the whole PBL. We also found that the state-of-the-art photochemical model tends to underestimate oxygenated VOCs at upper layers, resulting in overestimation of the degree of VOCs-limited regime. Therefore, thorough vertical measurements of VOCs to accurately diagnose O3 precursor sensitivity is in urgent need for the development of effective O3 control strategies.

4.
Environ Sci Technol ; 58(20): 8815-8824, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38733566

RESUMEN

This study presents the measurement of photochemical precursors during the lockdown period from January 23, 2020, to March 14, 2020, in Chengdu in response to the coronavirus (COVID-19) pandemic. To derive the lockdown impact on air quality, the observations are compared to the equivalent periods in the last 2 years. An observation-based model is used to investigate the atmospheric oxidation capacity change during lockdown. OH, HO2, and RO2 concentrations are simulated, which are elevated by 42, 220, and 277%, respectively, during the lockdown period, mainly due to the reduction in nitrogen oxides (NOx). However, the radical turnover rates, i.e., OH oxidation rate L(OH) and local ozone production rate P(O3), which determine the secondary intermediates formation and O3 formation, only increase by 24 and 48%, respectively. Therefore, the oxidation capacity increases slightly during lockdown, which is partly attributed to unchanged alkene concentrations. During the lockdown, alkene ozonolysis seems to be a significant radical primary source due to the elevated O3 concentrations. This unique data set during the lockdown period highlights the importance of controlling alkene emission to mitigate secondary pollution formation in Chengdu and may also be applicable in other regions of China given an expected NOx reduction due to the rapid transformation to electrified fleets in the future.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Oxidación-Reducción , Ozono , China , Atmósfera/química , Óxidos de Nitrógeno/análisis , Monitoreo del Ambiente , SARS-CoV-2 , Humanos
5.
Biology (Basel) ; 13(5)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38785790

RESUMEN

The cloning of resistance-related genes CsROP5/CsROP10 and the analysis of their mechanism of action provide a theoretical basis for the development of molecular breeding of disease-resistant cucumbers. The structure domains of two Rho-related guanosine triphosphatases from plant (ROP) genes were systematically analyzed using the bioinformatics method in cucumber plants, and the genes CsROP5 (Cucsa.322750) and CsROP10 (Cucsa.197080) were cloned. The functions of the two genes were analyzed using reverse-transcription quantitative PCR (RT-qPCR), virus-induced gene silencing (VIGS), transient overexpression, cucumber genetic transformation, and histochemical staining technology. The conserved elements of the CsROP5/CsROP10 proteins include five sequence motifs (G1-G5), a recognition site for serine/threonine kinases, and a hypervariable region (HVR). The knockdown of CsROP10 through VIGS affected the transcript levels of ABA-signaling-pathway-related genes (CsPYL, CsPP2Cs, CsSnRK2s, and CsABI5), ROS-signaling-pathway-related genes (CsRBOHD and CsRBOHF), and defense-related genes (CsPR2 and CsPR3), thereby improving cucumber resistance to Corynespora cassiicola. Meanwhile, inhibiting the expression of CsROP5 regulated the expression levels of ROS-signaling-pathway-related genes (CsRBOHD and CsRBOHF) and defense-related genes (CsPR2 and CsPR3), thereby enhancing the resistance of cucumber to C. cassiicola. Overall, CsROP5 and CsROP10 may participate in cucumber resistance to C. cassiicola through the ROS and ABA signaling pathways.

6.
Mol Plant ; 17(6): 900-919, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38704640

RESUMEN

Although both protein arginine methylation (PRMT) and jasmonate (JA) signaling are crucial for regulating plant development, the relationship between these processes in the control of spikelet development remains unclear. In this study, we used the CRISPR/Cas9 technology to generate two OsPRMT6a loss-of-function mutants that exhibit various abnormal spikelet structures. Interestingly, we found that OsPRMT6a can methylate arginine residues in JA signal repressors OsJAZ1 and OsJAZ7. We showed that arginine methylation of OsJAZ1 enhances the binding affinity of OsJAZ1 with the JA receptors OsCOI1a and OsCOI1b in the presence of JAs, thereby promoting the ubiquitination of OsJAZ1 by the SCFOsCOI1a/OsCOI1b complex and degradation via the 26S proteasome. This process ultimately releases OsMYC2, a core transcriptional regulator in the JA signaling pathway, to activate or repress JA-responsive genes, thereby maintaining normal plant (spikelet) development. However, in the osprmt6a-1 mutant, reduced arginine methylation of OsJAZ1 impaires the interaction between OsJAZ1 and OsCOI1a/OsCOI1b in the presence of JAs. As a result, OsJAZ1 proteins become more stable, repressing JA responses, thus causing the formation of abnormal spikelet structures. Moreover, we discovered that JA signaling reduces the OsPRMT6a mRNA level in an OsMYC2-dependent manner, thereby establishing a negative feedback loop to balance JA signaling. We further found that OsPRMT6a-mediated arginine methylation of OsJAZ1 likely serves as a switch to tune JA signaling to maintain normal spikelet development under harsh environmental conditions such as high temperatures. Collectively, our study establishes a direct molecular link between arginine methylation and JA signaling in rice.


Asunto(s)
Arginina , Ciclopentanos , Oryza , Oxilipinas , Proteínas de Plantas , Proteína-Arginina N-Metiltransferasas , Transducción de Señal , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Oryza/crecimiento & desarrollo , Oryza/genética , Oryza/metabolismo , Arginina/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Metilación , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Regulación de la Expresión Génica de las Plantas
7.
Commun Biol ; 7(1): 628, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789612

RESUMEN

Generating genetic diversity lies at the heart of directed evolution which has been widely used to engineer genetic parts and gene circuits in synthetic biology. With the ever-expanding application of directed evolution, different approaches of generating genetic diversity are required to enrich the traditional toolbox. Here we show in vitro generation of genetic diversity for directed evolution by error-prone artificial DNA synthesis (epADS). This approach comprises a three-step process which incorporates base errors randomly generated during chemical synthesis of oligonucleotides under specific conditions into the target DNA. Through this method, 200 ~ 4000 folds of diversification in fluorescent strength have been achieved in genes encoding fluorescent proteins. EpADS has also been successfully used to diversify regulatory genetic parts, synthetic gene circuits and even increase microbial tolerance to carbenicillin in a short time period. EpADS would be an alternative tool for directed evolution which may have useful applications in synthetic biology.


Asunto(s)
ADN , Evolución Molecular Dirigida , Variación Genética , Evolución Molecular Dirigida/métodos , ADN/genética , Biología Sintética/métodos , Oligonucleótidos/genética , Escherichia coli/genética , Escherichia coli/metabolismo
8.
Cell Commun Signal ; 22(1): 168, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454413

RESUMEN

BACKGROUND: The effectiveness of anti-programmed cell death protein 1(PD-1)/programmed cell death 1 ligand 1(PD-L1) therapy in treating certain types of cancer is associated with the level of PD-L1. However, this relationship has not been observed in colorectal cancer (CRC), and the underlying regulatory mechanism of PD-L1 in CRC remains unclear. METHODS: Binding of TMEM160 to PD-L1 was determined by co-immunoprecipitation (Co-IP) and GST pull-down assay.The ubiquitination levels of PD-L1 were verified using the ubiquitination assay. Phenotypic experiments were conducted to assess the role of TMEM160 in CRC cells. Animal models were employed to investigate how TMEM160 contributes to tumor growth.The expression and clinical significance of TMEM160 and PD-L1 in CRC tissues were evaluated by immunohistochemistry(IHC). RESULTS: In our study, we made a discovery that TMEM160 interacts with PD-L1 and plays a role in stabilizing its expression within a CRC model. Furthermore, we demonstrated that TMEM160 hinders the ubiquitination-dependent degradation of PD-L1 by competing with SPOP for binding to PD-L1 in CRC cells. Regarding functionality, the absence of TMEM160 significantly inhibited the proliferation, invasion, metastasis, clonogenicity, and radioresistance of CRC cells, while simultaneously enhancing the cytotoxic effect of CD8 + T cells on tumor cells. Conversely, the upregulation of TMEM160 substantially increased these capabilities. In severely immunodeficient mice, tumor growth derived from lentiviral vector shTMEM160 cells was lower compared with that derived from shNC control cells. Furthermore, the downregulation of TMEM160 significantly restricted tumor growth in immune-competent BALB/c mice. In clinical samples from patients with CRC, we observed a strong positive correlation between TMEM160 expression and PD-L1 expression, as well as a negative correlation with CD8A expression. Importantly, patients with high TMEM160 expression exhibited a worse prognosis compared with those with low or no TMEM160 expression. CONCLUSIONS: Our study reveals that TMEM160 inhibits the ubiquitination-dependent degradation of PD-L1 that is mediated by SPOP, thereby stabilizing PD-L1 expression to foster the malignant progress, radioresistance, and immune evasion of CRC cells. These findings suggest that TMEM160 holds potential as a target for the treatment of patients with CRC.


Asunto(s)
Neoplasias Colorrectales , Animales , Humanos , Ratones , Antígeno B7-H1/metabolismo , Linfocitos T CD8-positivos , Neoplasias Colorrectales/patología , Linfocitos Infiltrantes de Tumor , Proteínas Nucleares , Proteínas Represoras , Escape del Tumor
9.
Nicotine Tob Res ; 26(8): 1022-1028, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38381598

RESUMEN

INTRODUCTION: In April 2021, the U.S. Food and Drug Administration (FDA) announced its intention to ban the sale of menthol cigarettes and cigars. Decades of research support the premise that a menthol ban will reduce initiation and disparities in tobacco-related disease among menthol smokers. The tobacco industry opposed such a policy and worked for decades to shape public opposition. Social media discourse can inform our understanding of public opinion about the proposed ban and guide communication strategies and policy implementation. AIMS AND METHODS: This research employed a mixed-methods design to explore TikTok posts discussing the announced menthol ban. Using a TikTok web scraper to extract all content in the #mentholban hashtag (n = 171), we coded for 11 themes, characterized content with descriptive statistics, and created a semantic network of co-occurring hashtags. RESULTS: We found primarily negative attitudes towards the U.S. ban announcement and a large volume of menthol "hacks" to circumvent the bans. Our semantic network analysis revealed strong co-occurrences between #mentholban and popularity-seeking hashtags. The metadata associated with each TikTok demonstrated that most posters in #mentholban are not "influencers" in the sense of having many followers, aside from a few niche organizations with multiple posts. We found that perceived political and racial motivations shaped posters' assessments of the menthol ban. Furthermore, we uncovered how individuals and organizational actors shaped menthol ban content on TikTok. CONCLUSIONS: Our study indicates targeted marketing from alternative menthol product companies and advocacy organizations. The latter of these organizations is more likely to saturate the TikTok landscape with multiple posts and strategic hashtags. IMPLICATIONS: This study pursued an exploration of tobacco policy discussion on TikTok, specifically related to the FDA-proposed menthol ban. TikTok is a newer platform and our study provides early evidence of policy discussion emerging there, including the types of accounts creating the content and their valence toward the policy.


Asunto(s)
Mentol , Productos de Tabaco , Humanos , Estados Unidos , Productos de Tabaco/legislación & jurisprudencia , Medios de Comunicación Sociales , United States Food and Drug Administration , Industria del Tabaco/legislación & jurisprudencia , Opinión Pública
10.
Cancer Chemother Pharmacol ; 93(6): 587-593, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38402561

RESUMEN

BACKGROUND AND OBJECTIVES: Proteinuria is a common complication after the application of bevacizumab therapy in patients with metastatic colorectal cancer, and severe proteinuria can lead to discontinuation of the drug. There is a lack of sophisticated means to predict bevacizumab-induced proteinuria, so the present study aims to predict bevacizumab-induced proteinuria using peripheral venous blood samples. METHODS: A total of 122 subjects were enrolled and underwent pre-treatment plasma markers, and we followed them for six months with proteinuria as the endpoint event. We then analyzed the clinical features and plasma markers for grade ≥ 2 proteinuria occurrence using machine learning to construct a model with predictive utility. RESULTS: One hundred sixteen subjects were included in the statistical analysis. We found that high baseline systolic blood pressure, low baseline HGF, high baseline ET1, high baseline MMP2, and high baseline ACE1 were risk factors for the development of grade ≥ 2 proteinuria in patients with metastatic colorectal cancer who received bevacizumab. Then, we constructed a support vector machine model with a sensitivity of 0.889, a specificity of 0.918, a precision of 0.615, and an F1 score of 0.727. CONCLUSION: We constructed a machine learning model for predicting grade ≥ 2 bevacizumab-induced proteinuria, which may provide proteinuria risk assessment for applying bevacizumab in patients with metastatic colorectal cancer.


Asunto(s)
Bevacizumab , Neoplasias Colorrectales , Aprendizaje Automático , Proteinuria , Humanos , Bevacizumab/efectos adversos , Bevacizumab/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Proteinuria/inducido químicamente , Masculino , Femenino , Persona de Mediana Edad , Anciano , Antineoplásicos Inmunológicos/efectos adversos , Metástasis de la Neoplasia , Biomarcadores/sangre , Factores de Riesgo
11.
Recent Pat Anticancer Drug Discov ; 19(2): 146-153, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38214354

RESUMEN

BACKGROUND: Chlorogenic acid (CA, United States Patent No. 10772340), a natural biologically active food ingredient, displays potent antitumor activity against a variety of cancer cells. However, the mechanism underlying its anticancer effect is not well elucidated. OBJECTIVE: In the present study, we hope to dissect the mechanism underlying the anticancer effects of CA in pancreatic cancer cells. METHODS: The cytotoxicity of CA in pancreatic cancer cells was determined by MTT assay. Flow cytometry was performed to evaluate the cells apoptosis, while a clonogenic assay was carried out to check the colony formation of cancer cells. Transwell assay was performed to assess the cells migration and invasion. The protein expression of AKT/GSK-3ß/ß-catenin signaling pathway was detected by Western Blot. RESULTS: Our data indicated that CA inhibited the proliferation of PANC-28 and PANC-1 cells in a dose and time-dependent manner. CA was able to inhibit colony formation, migration, and invasion ability and trigger apoptosis in PANC-28 and PANC-1 cells. Further study showed that CA down-regulated the expression of AKT, p-AKT(Thr308), p-GSK-3ß(Ser9), ß-catenin, N-cadherin, and vimentin while enhancing the expression of cleaved-caspase 3 and cleaved-caspase 7 in PANC-28 and PANC-1 cells. CONCLUSION: Our study provides significant evidence that CA is able to inhibit the growth of pancreatic cancer via the AKT/GSK-3ß/ß-catenin signaling pathway.


Asunto(s)
Neoplasias Pancreáticas , Proteínas Proto-Oncogénicas c-akt , Humanos , Apoptosis , beta Catenina/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Ácido Clorogénico/farmacología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Patentes como Asunto , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
12.
Adv Mater ; 36(2): e2306928, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37672748

RESUMEN

Artificial muscles, providing safe and close interaction between humans and machines, are essential in soft robotics. However, their insufficient deformation, output force, or configurability usually limits their applications. Herein, this work presents a class of lightweight fabric-lattice artificial muscles (FAMs) that are pneumatically actuated with large contraction ratios (up to 87.5%) and considerable output forces (up to a load of 20 kg, force-to-weight ratio of over 250). The developed FAMs consist of a group of active air chambers that are zigzag connected into a lattice through passive connecting layers. The geometry of these fabric components is programmable to convert the in-plane lattice of FAMs into out-of-plane configurations (e.g., arched and cylindrical) capable of linear/radial contraction. This work further demonstrates that FAMs can be configured for various soft robotic applications, including the powerful robotic elbow with large motion range and high load capability, the well-fitting assistive shoulder exosuit that can reduce muscle activity during abduction, and the adaptive soft gripper that can grasp irregular objects. These results show the unique features and broad potential of FAMs for high-performance soft robots.


Asunto(s)
Robótica , Humanos , Robótica/métodos , Músculos/fisiología , Movimiento , Movimiento (Física) , Fenómenos Mecánicos
13.
Int J Biol Macromol ; 257(Pt 2): 128728, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38092101

RESUMEN

Trichinellosis is a zoonotic parasitic disease that poses threats to human health, the meat industry, food safety, and huge financial losses. The critical stage of Trichinella spiralis (T. spiralis) infection is the invasion of intestinal larvae into the host's intestinal epithelial cells (IECs). T. spiralis Cathepsin B (TsCB) specifically interacts with IECs to facilitate the invasion of larvae. This study aims to look at how TsCB affects mouse IECs. TsCB was successfully cloned, expressed, and characterized, demonstrating its natural cysteine protease hydrolysis activity. A total of 140 proteins that interact with rTsCB were identified by GST pull-down combined with LC-MS/MS, including type I collagen, an essential component of the host's intestinal epithelial barrier system and intimately related to intestinal epithelial damage. TsCB transcription and expression levels rise, whereas type I collagen in the host's intestinal mucosa declines when the T. spiralis larvae invaded. Besides, it was discovered that TsCB bound to and degraded type I collagen of the host's intestine. This research can serve as a foundation for clarifying how T. spiralis invades the host's intestinal barrier and might provide information on potential targets for the creation of novel treatments to treat parasite illnesses.


Asunto(s)
Trichinella spiralis , Triquinelosis , Animales , Ratones , Humanos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Catepsina B/genética , Cromatografía Liquida , Espectrometría de Masas en Tándem , Intestinos , Triquinelosis/metabolismo , Triquinelosis/parasitología , Larva/metabolismo , Ratones Endogámicos BALB C , Proteínas del Helminto/metabolismo
14.
Cell Calcium ; 117: 102839, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134531

RESUMEN

Ca2+ signaling is essential for cardiac contractility and excitability in heart function and remodeling. Intriguingly, little is known about the role of a new family of ion channels, the endo-lysosomal non-selective cation "two-pore channel" (TPCs) in heart function. Here we have used double TPC knock-out mice for the 1 and 2 isoforms of TPCs (Tpcn1/2-/-) and evaluated their cardiac function. Doppler-echocardiography unveils altered left ventricular (LV) systolic function associated with a LV relaxation impairment. In cardiomyocytes isolated from Tpcn1/2-/- mice, we observed a reduction in the contractile function with a decrease in the sarcoplasmic reticulum Ca2+ content and a reduced expression of various key proteins regulating Ca2+ stores, such as calsequestrin. We also found that two main regulators of the energy metabolism, AMP-activated protein kinase and mTOR, were down regulated. We found an increase in the expression of TPC1 and TPC2 in a model of transverse aortic constriction (TAC) mice and in chronically isoproterenol infused WT mice. In this last model, adaptive cardiac hypertrophy was reduced by Tpcn1/2 deletion. Here, we propose a central role for TPCs and lysosomes that could act as a hub integrating information from the excitation-contraction coupling mechanisms, cellular energy metabolism and hypertrophy signaling.


Asunto(s)
Canales de Calcio , Canales de Dos Poros , Ratones , Animales , Canales de Calcio/metabolismo , Lisosomas/metabolismo , Transducción de Señal , Ratones Noqueados , Cardiomegalia/metabolismo , NADP/metabolismo , Calcio/metabolismo , Señalización del Calcio
15.
Virus Res ; 339: 199250, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-37865350

RESUMEN

Evidence is emerging on the roles of long noncoding RNAs (lncRNAs) as regulatory factors in a variety of viral infection processes, but the mechanisms underlying their functions in coxsackievirus group B type3 (CVB3)-induced acute viral myocarditis have not been explicitly delineated. We previously demonstrated that CVB3 infection decreases miRNA-21 expression; however, lncRNAs that regulate the miRNA-21-dependent CVB3 disease process have yet to be identified. To evaluate lncRNAs upstream of miRNA-21, differentially expressed lncRNAs in CVB3-infected mouse hearts were identified by microarray analysis and lncRNA/miRNA-21 interactions were predicted bioinformatically. MEG3 was identified as a candidate miRNA-21-interacting lncRNA upregulated in CVB3-infected mouse hearts. MEG3 expression was verified to be upregulated in HeLa cells 48 h post CVB3 infection and to act as a competitive endogenous RNA of miRNA-21. MEG3 knockdown resulted in the upregulation of miRNA-21, which inhibited CVB3 replication by attenuating P38-MAPK signaling in vitro and in vivo. Knockdown of MEG3 expression before CVB3 infection inhibited viral replication in mouse hearts and alleviated cardiac injury, which improved survival. Furthermore, the knockdown of CREB5, which was predicted bioinformatically to function upstream of MEG3, was demonstrated to decrease MEG3 expression and CVB3 viral replication. This study identifies the function of the lncRNA MEG3/miRNA-21/P38 MAPK axis in the process of CVB3 replication, for which CREB5 could serve as an upstream modulator.


Asunto(s)
Infecciones por Coxsackievirus , Enterovirus , MicroARNs , Miocarditis , ARN Largo no Codificante , Virosis , Animales , Humanos , Ratones , Infecciones por Coxsackievirus/complicaciones , Infecciones por Coxsackievirus/genética , Enterovirus/genética , Enterovirus Humano B/genética , Enterovirus Humano B/metabolismo , Células HeLa/virología , MicroARNs/genética , MicroARNs/metabolismo , Miocarditis/genética , Miocarditis/metabolismo , Miocarditis/virología , ARN Largo no Codificante/genética , Replicación Viral
16.
PLoS One ; 18(11): e0290674, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37976309

RESUMEN

Online reviews and customer Q&As have emerged as two vital forms of electronic word-of-mouth (eWOM) that significantly influence consumer decisions in e-commerce. Yet, a comprehensive understanding of the individual and combined roles of these eWOM types in shaping market dynamics remains elusive. This study addresses this research gap by tracking and analyzing three months of eWOM and sales data for 120 laptops on Amazon, comprising 7,205 online reviews, 6,365 customer Q&A questions, and 7,419 answers. Leveraging the Panel Vector Autoregression (PVAR) model and STATA16.0 software, we unravel the intricate dynamics between online reviews, customer Q&As, and laptop sales. The empirical results reveal distinctive influence mechanisms of online reviews and customer Q&As on product sales, with review volume and answer valence positively affecting sales. Importantly, answer volume was found to stimulate online reviews and enhance their valence. Our study elucidates the interplay among online reviews, customer Q&As, and product sales, underscoring the need for future research on multi-type eWOM. Further, the insights gleaned offer valuable guidance for online platforms and retailers to strategize their eWOM management.


Asunto(s)
Comercio , Programas Informáticos
17.
Plant Cell ; 35(12): 4325-4346, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37738653

RESUMEN

CYP78A, a cytochrome P450 subfamily that includes rice (Oryza sativa L.) BIG GRAIN2 (BG2, CYP78A13) and Arabidopsis thaliana KLUH (KLU, CYP78A5), generate an unknown mobile growth signal (referred to as a CYP78A-derived signal) that increases grain (seed) size. However, the mechanism by which the CYP78A pathway increases grain size remains elusive. Here, we characterized a rice small grain mutant, small grain4 (smg4), with smaller grains than its wild type due to restricted cell expansion and cell proliferation in spikelet hulls. SMG4 encodes a multidrug and toxic compound extrusion (MATE) transporter. Loss of function of SMG4 causes smaller grains while overexpressing SMG4 results in larger grains. SMG4 is mainly localized to endoplasmic reticulum (ER) exit sites (ERESs) and partially localized to the ER and Golgi. Biochemically, SMG4 interacts with coat protein complex Ⅱ (COPⅡ) components (Sar1, Sec23, and Sec24) and CYP78As (BG2, GRAIN LENGTH 3.2 [GL3.2], and BG2-LIKE 1 [BG2L1]). Genetically, SMG4 acts, at least in part, in a common pathway with Sar1 and CYP78As to regulate grain size. In summary, our findings reveal a CYP78As-SMG4-COPⅡ regulatory pathway for grain size in rice, thus providing new insights into the molecular and genetic regulatory mechanism of grain size.


Asunto(s)
Arabidopsis , Oryza , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grano Comestible/genética , Semillas/genética , Arabidopsis/genética
18.
Sci Adv ; 9(38): eadi7133, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37729399

RESUMEN

Artificial muscles are promising in soft exoskeletons, locomotion robots, and operation machines. However, their performance in contraction ratio, output force, and dynamic response is often imbalanced and limited by materials, structures, or actuation principles. We present lightweight, high-contraction ratio, high-output force, and positive pressure-driven X-crossing pneumatic artificial muscles (X-PAMs). Unlike PAMs, our X-PAMs harness the X-crossing mechanism to directly convert linear motion along the actuator axis, achieving an unprecedented 92.9% contraction ratio and an output force of 207.9 Newtons per kilogram per kilopascal with excellent dynamic properties, such as strain rate (1603.0% per second), specific power (5.7 kilowatts per kilogram), and work density (842.9 kilojoules per meter cubed). These properties can overcome the slow actuation of conventional PAMs, providing robotic elbow, jumping robot, and lightweight gripper with fast, powerful performance. The robust design of X-PAMs withstands extreme environments, including high-temperature, underwater, and long-duration actuation, while being scalable to parallel, asymmetric, and ring-shaped configurations for potential applications.


Asunto(s)
Músculos , Robótica , Locomoción , Movimiento (Física)
19.
Nanoscale ; 15(38): 15573-15582, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37641947

RESUMEN

Combination therapy is an emerging strategy to overcome multidrug resistance (MDR) in hepatocellular carcinoma (HCC) chemotherapy treatment. However, the passive diffusion in traditional delivery systems greatly retards the approach and penetration of drugs into hepatocellular carcinoma cells and thus hinders the efficacy of combination therapy. Micro/nanomotors with autonomous locomotion in a tiny scale provide the possibility of tackling this issue. Herein, an active drug delivery micromotor platform delicately designed to load drugs with different physicochemical properties and enhance the drug permeability of cells is demonstrated for HCC chemotherapy treatment. The biocompatible micromotor platform Mg/PLGA/CHI comprised magnesium (Mg) coated with two polymer layers made of poly(lactic-co-glycolic acid) (PLGA) and chitosan (CHI), where the hydrophobic and hydrophilic drugs doxorubicin (Dox) and Curcumin (Cur) were loaded, respectively. The autonomous motion of the micromotors with velocity up to 45 µm s-1 greatly enhanced the diffusion of chemotherapeutic drugs and led to higher extracellular and intracellular drug distribution. Moreover, hydrogen produced during the motion eliminated the excess reactive oxygen species (ROS) in the human hepatocellular carcinoma (HepG2) cells. Compared with inert groups, the absorption of Dox and Cur from the active micromotors was about 2.9 and 1.5 times higher in human hepatocellular carcinoma (HepG2) cells. In addition, the anti-tumor activity also obviously improved at the micromotor concentration of 1 mg mL-1 (cell proliferation was reduced by almost 30%). Overall, this work proposes an approach based on loading different chemotherapy agents on an active delivery system to enhance drug permeability and overcome MDR and provides a potentially effective therapeutic strategy for the treatment of HCC.

20.
J Thromb Haemost ; 21(11): 3268-3278, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37207862

RESUMEN

BACKGROUND: X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection, and neoplasia (XMEN) disease is a primary immunodeficiency due to loss-of-function mutations in the gene encoding for magnesium transporter 1 (MAGT1). Furthermore, as MAGT1 is involved in the N-glycosylation process, XMEN disease is classified as a congenital disorder of glycosylation. Although XMEN-associated immunodeficiency is well described, the mechanisms underlying platelet dysfunction and those responsible for life-threatening bleeding events have never been investigated. OBJECTIVES: To assess platelet functions in patients with XMEN disease. METHODS: Two unrelated young boys, including one before and after hematopoietic stem cell transplantation, were investigated for their platelet functions, glycoprotein expression, and serum and platelet-derived N-glycans. RESULTS: Platelet analysis highlighted abnormal elongated cells and unusual barbell-shaped proplatelets. Platelet aggregation, integrin αIIbß3 activation, calcium mobilization, and protein kinase C activity were impaired between both patients. Strikingly, platelet responses to protease-activated receptor 1 activating peptide were absent at both low and high concentrations. These defects were also associated with decreased molecular weights of glycoprotein Ibα, glycoprotein VI, and integrin αIIb due to partial impairment of N-glycosylation. All these defects were corrected after hematopoietic stem cell transplantation. CONCLUSION: Our results highlight prominent platelet dysfunction related to MAGT1 deficiency and defective N-glycosylation in several platelet proteins that could explain the hemorrhages reported in patients with XMEN disease.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Magnesio , Masculino , Humanos , Magnesio/metabolismo , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Glicosilación , Herpesvirus Humano 4/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo
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