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1.
Cell Commun Signal ; 22(1): 168, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454413

RESUMO

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.


Assuntos
Neoplasias Colorretais , Animais , Humanos , Camundongos , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos , Neoplasias Colorretais/patologia , Linfócitos do Interstício Tumoral , Proteínas Nucleares , Proteínas Repressoras , Evasão Tumoral
2.
Artigo em Inglês | MEDLINE | ID: mdl-38402561

RESUMO

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.

3.
Nicotine Tob Res ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381598

RESUMO

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 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. 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 US 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. CONCLUSION: 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 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.

4.
Recent Pat Anticancer Drug Discov ; 19(2): 146-153, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38214354

RESUMO

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.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas c-akt , Humanos , Apoptose , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ácido Clorogênico/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Patentes como Assunto , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
5.
Adv Mater ; 36(2): e2306928, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37672748

RESUMO

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.


Assuntos
Robótica , Humanos , Robótica/métodos , Músculos/fisiologia , Movimento , Movimento (Física) , Fenômenos Mecânicos
6.
Int J Biol Macromol ; 257(Pt 2): 128728, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38092101

RESUMO

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.


Assuntos
Trichinella spiralis , Triquinelose , Animais , Camundongos , Humanos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Catepsina B/genética , Cromatografia Líquida , Espectrometria de Massas em Tandem , Intestinos , Triquinelose/metabolismo , Triquinelose/parasitologia , Larva/metabolismo , Camundongos Endogâmicos BALB C , Proteínas de Helminto/metabolismo
7.
Virus Res ; 339: 199250, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37865350

RESUMO

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.


Assuntos
Infecções por Coxsackievirus , Enterovirus , MicroRNAs , Miocardite , RNA Longo não Codificante , Viroses , Animais , Humanos , Camundongos , Infecções por Coxsackievirus/complicações , Infecções por Coxsackievirus/genética , Enterovirus/genética , Enterovirus Humano B/genética , Enterovirus Humano B/metabolismo , Células HeLa/virologia , MicroRNAs/genética , MicroRNAs/metabolismo , Miocardite/genética , Miocardite/metabolismo , Miocardite/virologia , RNA Longo não Codificante/genética , Replicação Viral
8.
Cell Calcium ; 117: 102839, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134531

RESUMO

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.


Assuntos
Canais de Cálcio , 60694 , Camundongos , Animais , Canais de Cálcio/metabolismo , Lisossomos/metabolismo , Transdução de Sinais , Camundongos Knockout , Cardiomegalia/metabolismo , NADP/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio
9.
PLoS One ; 18(11): e0290674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37976309

RESUMO

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.


Assuntos
Comércio , Software
10.
Sci Adv ; 9(38): eadi7133, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37729399

RESUMO

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.


Assuntos
Músculos , Robótica , Locomoção , Movimento (Física)
11.
Plant Cell ; 35(12): 4325-4346, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37738653

RESUMO

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.


Assuntos
Arabidopsis , Oryza , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grão Comestível/genética , Sementes/genética , Arabidopsis/genética
12.
Nanoscale ; 15(38): 15573-15582, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37641947

RESUMO

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.

13.
ACS Appl Mater Interfaces ; 15(20): 24034-24046, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159919

RESUMO

The emergence and innovation of three-dimensional (3D) bioprinting provide new development opportunities for tissue engineering and regenerative medicine. However, how to obtain bioinks with both biomimicry and manufacturability remains a great issue in 3D bioprinting. Developing intelligent responsive biomaterials is conducive to break through the current dilemma. Herein, a stepwise multi-cross-linking strategy concerning thermosensitive thiolated Pluronic F127 (PF127-SH) and hyaluronic acid methacrylate (HAMA) is proposed to achieve temperature-controlled 3D embedded bioprinting, specifically pre-cross-linking (Michael addition reaction) at low temperatures (4-20 °C) and subsequently self-assembly (hydrophobic interaction) in a high-temperature (30-37 °C) suspension bath as well as final photo-cross-linking (mainly thiol-ene "click" reaction). The unique stepwise cross-linking mechanism promises the thermosensitive bioink appropriate viscosity at different printing stages, making it possible to print complex structures with excellent shape fidelity and simultaneously maintain the biological activity of cells. In vitro studies reveal that 3D-printed hydrogels are beneficial for enhancing cell viability. Further, in vivo experiments demonstrate that cell-laden printed hydrogels significantly promote wound healing and re-epithelialization by modulating inflammation and accelerating collagen deposition and angiogenesis. Therefore, the proposed stepwise multi-cross-linking strategy is expected to accelerate the development of novel bioinks and promote the clinical applications of 3D bioprinting.


Assuntos
Bioimpressão , Tecidos Suporte , Tecidos Suporte/química , Bioimpressão/métodos , Impressão Tridimensional , Engenharia Tecidual , Hidrogéis/química , Cicatrização
14.
J Thromb Haemost ; 21(11): 3268-3278, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37207862

RESUMO

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.


Assuntos
Infecções por Vírus Epstein-Barr , Magnésio , Masculino , Humanos , Magnésio/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Glicosilação , Herpesvirus Humano 4/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo
15.
Int J Biol Macromol ; 240: 124364, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37044319

RESUMO

Three-dimensional (3D) bioprinting is a promising technique to construct heterogeneous architectures that mimic cell microenvironment. However, the current bioinks for 3D bioprinting usually show some limitations, such as low printing accuracy, unsatisfactory mechanical properties and compromised cytocompatibility. Herein, a novel bioink comprising hydroxyphenyl propionic acid-conjugated gelatin and tyramine-modified alginate is developed for printing 3D constructs. The bioink takes advantage of an ionic/covalent intertwined network that combines covalent bonds formed by photo-mediated redox reaction and ionic bonds formed by chelate effect. Benefiting from the thermosensitivity of gelatin and the double-crosslinking mechanism, the developed bioink shows controllable rheological behaviors, enhanced mechanical behavior, improved printing accuracy and structure stability. Moreover, the printed cell-laden hydrogels exhibit a homogeneous cell distribution and considerable cell survival because the pre-crosslinking of the bioink prevents cellular sedimentation and the visible light crosslinking mechanism preserves cell viability. Further in vivo studies demonstrate that resulting cell-laden hydrogels are beneficial for the reduction of inflammation response and the promotion of collagen deposition and angiogenesis, thereby improving the quality of skin wound healing. This convenient and effective strategy is of great significance for accelerating the development of multifunctional bioinks and broadening the biomedical applications of 3D bioprinting.


Assuntos
Engenharia Tecidual , Tecidos Suporte , Tecidos Suporte/química , Engenharia Tecidual/métodos , Gelatina/química , Alginatos/farmacologia , Alginatos/química , Impressão Tridimensional , Hidrogéis/farmacologia , Hidrogéis/química , Cicatrização
16.
Front Psychol ; 14: 1084180, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874871

RESUMO

The post-pandemic COVID-19 has been influential in accelerating the digital transformation of enterprises and business process virtualization. However, in a virtual working environment with no physical interaction, the psychological requirements of the communication between teleworkers and the negative impact of information systems are hindering the business process virtualization. Studying the relationship between the interaction between organizational members and job performance is an important part of organizational psychology. For an enterprise to maintain high-efficiency output, it is necessary to study psychological factors related to business process virtualization. This paper verified the factors hindering business process virtualization based on process virtualization theory (PVT). The research was implemented on a sample of 343 teleworkers in China enterprises. The structure of the model of this study includes two aspects that hinder the business process virtualization: the psychological requirements of teleworkers (Sensory requirements, Synchronism requirements, and Relationship requirements) and the negative effects of information systems (Information overload and Communication overload). The results show that teleworkers' sensory requirements, synchronism requirements, and communication overload negatively impact business process virtualization. However, unlike the results in the existing literature, the relationship requirements and information overload do not affect the business process virtualization. The results will help business managers, teleworkers, and information system developers develop strategies to address the negative factors hindering business process virtualization. In the so-called new "normal era," our research will help companies to create a successful virtual work environment.

17.
Res Pract Thromb Haemost ; 7(1): 100004, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36970741

RESUMO

Background: Blood platelet Ca2+ stores are regulated by 2 Ca2+-ATPases (SERCA2b and SERCA3). On thrombin stimulation, nicotinic acid adenosine dinucleotide phosphate mobilizes SERCA3-dependent stores, inducing early adenosine 5'-diphosphate (ADP) secretion, potentiating later SERCA2b-dependent secretion. Objectives: The aim of this study was to identify which ADP P2 purinergic receptor (P2Y1 and/or P2Y12) is(are) involved in the amplification of platelet secretion dependent on the SERCA3-dependent Ca2+ mobilization pathway (SERCA3 stores mobilization) as triggered by low concentration of thrombin. Methods: The study used the pharmacologic antagonists MRS2719 and AR-C69931MX, of the P2Y1 and P2Y12, respectively, as well as Serca3 -/- mice and mice exhibiting platelet lineage-specific inactivation of the P2Y1 or P2Y12 genes. Results: We found that in mouse platelets, pharmacological blockade or gene inactivation of P2Y12 but not of P2Y1 led to a marked inhibition of ADP secretion after platelet stimulation with low concentration of thrombin. Likewise, in human platelets, pharmacological inhibition of P2Y12 but not of P2Y1 alters amplification of thrombin-elicited secretion through SERCA2b stores mobilization. Finally, we show that early SERCA3 stores secretion of ADP is a dense granule secretion, based on parallel adenosine triphosphate and serotonin early secretion. Furthermore, early secretion involves a single granule, based on the amount of adenosine triphosphate released. Conclusion: Altogether, these results show that at low concentrations of thrombin, SERCA3- and SERCA2b-dependent Ca2+ mobilization pathways cross-talk via ADP and activation of the P2Y12, and not the P2Y1 ADP receptor. The relevance in hemostasis of the coupling of the SERCA3 and the SERCA2b pathways is reviewed.

18.
Genes (Basel) ; 14(3)2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36980878

RESUMO

DNA synthesis is widely used in synthetic biology to construct and assemble sequences ranging from short RBS to ultra-long synthetic genomes. Many sequence features, such as the GC content and repeat sequences, are known to affect the synthesis difficulty and subsequently the synthesis cost. In addition, there are latent sequence features, especially local characteristics of the sequence, which might affect the DNA synthesis process as well. Reliable prediction of the synthesis difficulty for a given sequence is important for reducing the cost, but this remains a challenge. In this study, we propose a new automated machine learning (AutoML) approach to predict the DNA synthesis difficulty, which achieves an F1 score of 0.930 and outperforms the current state-of-the-art model. We found local sequence features that were neglected in previous methods, which might also affect the difficulty of DNA synthesis. Moreover, experimental validation based on ten genes of Escherichia coli strain MG1655 shows that our model can achieve an 80% accuracy, which is also better than the state of art. Moreover, we developed the cloud platform SCP4SSD using an entirely cloud-based serverless architecture for the convenience of the end users.


Assuntos
Escherichia coli , Aprendizado de Máquina , Sequência de Bases , Escherichia coli/genética , Composição de Bases , DNA/genética
19.
J Integr Plant Biol ; 65(7): 1687-1702, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36897026

RESUMO

Pentatricopeptide repeat (PPR) proteins function in post-transcriptional regulation of organellar gene expression. Although several PPR proteins are known to function in chloroplast development in rice (Oryza sativa), the detailed molecular functions of many PPR proteins remain unclear. Here, we characterized a rice young leaf white stripe (ylws) mutant, which has defective chloroplast development during early seedling growth. Map-based cloning revealed that YLWS encodes a novel P-type chloroplast-targeted PPR protein with 11 PPR motifs. Further expression analyses showed that many nuclear- and plastid-encoded genes in the ylws mutant were significantly changed at the RNA and protein levels. The ylws mutant was impaired in chloroplast ribosome biogenesis and chloroplast development under low-temperature conditions. The ylws mutation causes defects in the splicing of atpF, ndhA, rpl2, and rps12, and editing of ndhA, ndhB, and rps14 transcripts. YLWS directly binds to specific sites in the atpF, ndhA, and rpl2 pre-mRNAs. Our results suggest that YLWS participates in chloroplast RNA group II intron splicing and plays an important role in chloroplast development during early leaf development.


Assuntos
Oryza , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Plastídeos/metabolismo , RNA de Cloroplastos/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Oryza/metabolismo , Regulação da Expressão Gênica de Plantas/genética
20.
Acta Pharm Sin B ; 13(1): 284-297, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36811095

RESUMO

Biofilms are closely associated with the tough healing and dysfunctional inflammation of chronic wounds. Photothermal therapy (PTT) emerged as a suitable alternative which could destroy the structure of biofilms with local physical heat. However, the efficacy of PTT is limited because the excessive hyperthermia could damage surrounding tissues. Besides, the difficult reserve and delivery of photothermal agents makes PTT hard to eradicate biofilms as expectation. Herein, we present a GelMA-EGF/Gelatin-MPDA-LZM bilayer hydrogel dressing to perform lysozyme-enhanced PTT for biofilms eradication and a further acceleration to the repair of chronic wounds. Gelatin was used as inner layer hydrogel to reserve lysozyme (LZM) loaded mesoporous polydopamine (MPDA) (MPDA-LZM) nanoparticles, which could rapidly liquefy while temperature rising so as to achieve a bulk release of nanoparticles. MPDA-LZM nanoparticles serve as photothermal agents with antibacterial capability, could deeply penetrate and destroy biofilms. In addition, the outer layer hydrogel consisted of gelatin methacryloyl (GelMA) and epidermal growth factor (EGF) promoted wound healing and tissue regeneration. It displayed remarkable efficacy on alleviating infection and accelerating wound healing in vivo. Overall, the innovative therapeutic strategy we came up with has significant effect on biofilms eradication and shows promising application in promoting the repair of clinical chronic wounds.

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