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1.
Proc Natl Acad Sci U S A ; 119(31): e2205469119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35895684

RESUMO

T regulatory (Treg) cells are essential for self-tolerance whereas they are detrimental for dampening the host anti-tumor immunity. How Treg cells adapt to environmental signals to orchestrate their homeostasis and functions remains poorly understood. Here, we identified that transcription factor EB (TFEB) is induced by host nutrition deprivation or interleukin (IL)-2 in CD4+ T cells. The loss of TFEB in Treg cells leads to reduced Treg accumulation and impaired Treg function in mouse models of cancer and autoimmune disease. TFEB intrinsically regulates genes involved in Treg cell differentiation and mitochondria function while it suppresses expression of proinflammatory cytokines independently of its established roles in autophagy. This coordinated action is required for mitochondria integrity and appropriate lipid metabolism in Treg cells. These findings identify TFEB as a critical regulator for orchestrating Treg generation and function, which may contribute to the adaptive responses of T cells to local environmental cues.


Assuntos
Adaptação Fisiológica , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Mitocôndrias , Neoplasias , Linfócitos T Reguladores , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Animais , Doenças Autoimunes/imunologia , Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Modelos Animais de Doenças , Interleucina-2/metabolismo , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Chemistry ; 30(20): e202303852, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38299784

RESUMO

Recently, extensive works have focused on increasing the dissymmetry factors (glum) of various circularly polarized luminescence (CPL) materials, which is one of the most important factors for future applications of CPL. Herein, we designed a chiral co-assembled liquid crystal polymer (LCP) PTZ@R/S-PB2, which was prepared by chiral binary co-polymer (R/S-PB2) doped with achiral phenothiazine derivation dye (PTZ). For comparison, ternary co-polymerized LCP (R/S-PT) was synthesized by co-polymerizing with mesogenic monomer, chiral monomer and emissive monomer. Both PTZ@R/S-PB2 and R/S-PT showed aggregation-induced emission (AIE) properties. Interestingly, the CPL signals of both PTZ@R/S-PB2 and R/S-PT were reversed and amplified after thermal annealing treatment. The |glum| values of the co-assembled PTZ@R/S-PB2 were up to 0.13 at a 32 nm thickness, which was 5.4 times that of R/S-PT (|glum|=0.024). This is due to PTZ@R/S-PB2 could form more orderly chiral co-assembly structures. Noticeably, increasing the LCP film thickness could further improve the glum value, and the maximum glum of PTZ@R/S-PB2 could be enhanced to +0.91/-0.82 at a 220 nm thickness.

3.
Opt Lett ; 48(10): 2764-2767, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37186760

RESUMO

We implement faithful multimode fiber (MMF) image transmission by a self-attention-based neural network. Compared with a real-valued artificial neural network (ANN) based on a convolutional neural network (CNN), our method utilizes a self-attention mechanism to achieve a higher image quality. The enhancement measure (EME) and structural similarity (SSIM) of the dataset collected in the experiment improved by 0.79 and 0.04; the total number of parameters can be reduced by up to 25%. To enhance the robustness of the neural network to MMF bending in image transmission, we use a simulation dataset to prove that the hybrid training method is helpful in MMF transmission of a high-definition image. Our findings may pave the way for simpler and more robust single-MMF image transmission schemes with hybrid training; SSIM on datasets under different disturbances improve by 0.18. This system has the potential to be applied to various high-demand image transmission tasks, such as endoscopy.

4.
Chemistry ; 29(22): e202204039, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36691189

RESUMO

Circularly polarized luminescence (CPL) has attracted much interest due to its potential applications on chiral photonic techniques and optoelectronic materials science. As known, dissymmetry factor (gem ) of CPL is one essential factor for evaluating the features of CPL-active materials. Much attention has focused on how to increase the gem value, which is one of the most important issues for CPL practical applications. Recently, more and more works have demonstrated that chiral supramolecular could provide the significant strategy to improve the gem value through the orderly helical superstructure of chiral building blocks. Normally, this kind of chiral supramolecular assembly process can be accompanied by chirality transfer and induction mechanism, which can promote the amplification effect on the induced CPL of achiral dyes. In this review, we fully summarized recent advances on the induced CPL-active materials of chiral supramolecular co-assemblies, their applications in circularly polarized organic light-emitting diodes (CP-OLEDs) and current challenges.

5.
Oral Dis ; 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37448205

RESUMO

OBJECTIVES: Exosomes derived from stem cells are a potential cell-free tool for tissue regeneration with therapeutic potential. However, its application in cementum repair is unclear. This study aimed to investigate the effect of human periodontal ligament stem cell-derived exosomes on the biological activity of cementoblasts, the main effector cells in cementum synthesis. MATERIALS AND METHODS: OCCM-30 cementoblasts were cultured with various human periodontal ligament stem cell-derived exosome concentrations. OCCM-30 cells proliferation, migration, and cementogenic mineralization were examined, along with the gene and protein expression of factors associated with cementoblastic mineralization. RESULTS: Exosomal promoted the migration, proliferation, and mineralization of OCCM-30 cells. The exosome-treated group significantly increased the expression of cementogenic-related genes and proteins. Furthermore, the expression of p-PI3K and p-AKT was enhanced by exosome administration. Treatment with a PI3K/AKT inhibitor markedly attenuated the gene and protein expression of cementoblastic factors, and this effect was partially reversed by exosome administration. CONCLUSIONS: Human periodontal ligament stem cell-derived exosomes can promote the activity of cementoblasts via the PI3K/AKT signaling pathway, providing a scientific basis for promoting the repair process in orthodontically induced inflammatory root resorption.

6.
BMC Pediatr ; 23(1): 250, 2023 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210514

RESUMO

BACKGROUND: It is proposed that the development of parenteral nutrition-associated cholestasis (PNAC) was significantly associated with preterm birth, low birth weight, infection, etc.; however, the etiology and pathogenesis of PNAC are not fully understood. Most of the studies examining PNAC-associated risk factors were single-center studies with relatively small sample sizes. OBJECTIVE: To analyze the risk factors associated with PNAC in preterm infants in China. METHODS: This is a retrospective multicenter observational study. Clinical data on the effect of multiple oil-fat emulsions (soybean oil-medium chain triglycerides-olive oil-fish oil, SMOF) in preterm infants were collected from a prospective multicenter randomized controlled study. A secondary analysis was performed in which preterm infants were divided into the PNAC group and the non-PNAC group based on the PNAC status. RESULTS: A total of 465 cases very preterm infants or very low birth weight infants were included in the study in which 81 cases were assigned to the PNAC group and 384 cases were assigned to the non-PNAC group. The PNAC group had a lower mean gestational age, lower mean birth weight, longer duration of invasive and non-invasive mechanical ventilation, a longer duration oxygen support, and longer hospital stay (P < 0.001 for all). The PNAC group had higher respiratory distress syndrome, hemodynamically significant patent ductus arteriosus, necrotizing enterocolitis (NEC) with stage II or higher, surgically treated NEC, late-onset sepsis, metabolic bone disease, and extrauterine growth retardation (EUGR) compared to the non-PNAC group (P < 0.05 for all). In contrast with the non-PNAC group, the PNAC group received a higher maximum dose of amino acids and fat emulsion, more medium/long-chain fatty emulsion, less SMOF, had a longer duration of parenteral nutrition, lower rates of breastfeeding, higher incidence of feeding intolerance (FI), more accumulated days to achieve total enteral nutrition, less accumulated days of total calories up to standard 110 kcal/kg/day and slower velocity of weight growth (P < 0.05 for all). Logistic regression analysis indicated that the maximum dose of amino acids (OR, 5.352; 95% CI, 2.355 to 12.161), EUGR (OR, 2.396; 95% CI, 1.255 to 4.572), FI (OR, 2.581; 95% CI, 1.395 to 4.775), surgically treated NEC (OR, 11.300; 95% CI, 2.127 ~ 60.035), and longer total hospital stay (OR, 1.030; 95% CI, 1.014 to 1.046) were independent risk factors for the development of PNAC. SMOF (OR, 0.358; 95% CI, 0.193 to 0.663) and breastfeeding (OR, 0.297; 95% CI, 0.157 to 0.559) were protective factors for PNAC. CONCLUSIONS: PNAC can be reduced by optimizing the management of enteral and parenteral nutrition and reducing gastrointestinal comorbidities in preterm infants.


Assuntos
Colestase , Nascimento Prematuro , Feminino , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Emulsões/química , Peso ao Nascer , Estudos Prospectivos , Nascimento Prematuro/etiologia , Colestase/etiologia , Colestase/epidemiologia , Nutrição Parenteral/efeitos adversos , Recém-Nascido de muito Baixo Peso , Aminoácidos , Fatores de Risco
7.
Int J Mol Sci ; 24(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37108296

RESUMO

Stem cells have differentiation and regulation functions. Here, we discussed the impact of cell culture density on stem cell proliferation, osteoblastogenesis, and regulation. To discuss the effect of the initial culture density of human periodontal ligament stem cells (hPDLSCs) on the osteogenic differentiation of autologous cells, we found that the hPDLSC proliferation rate decreased with an increase in the initial plating density (0.5-8 × 104 cells/cm2) for the 48 h culture cycle. After hPDLSCs induced osteogenic differentiation for 14 days with different initial cell culture densities, the expression of osteoprotegerin (OPG) and runt-related transcription factor 2(RUNX2) and the OPG/ Receptor Activator of Nuclear Factor-κ B Ligand (RANKL) ratio were the highest in the hPDLSCs initially plated at a density of 2 × 104 cells/cm2, and the average cell calcium concentration was also the highest. To study hPDLSCs regulating the osteoblastic differentiation of other cells, we used 50 µg/mL of secreted exosomes derived from hPDLSCs cultured using different initial cell densities to induce human bone marrow stromal cell (hBMSC) osteogenesis. After 14 days, the results indicated that the gene expression of OPG, Osteocalcin(OCN,)RUNX2, and osterix and the OPG/RANKL ratio were the highest in the 2 × 104 cells/cm2 initial cell density group, and the average calcium concentration was also the highest. This provides a new idea for the clinical application of stem cell osteogenesis.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Osteogênese/genética , Ligamento Periodontal , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Cálcio/metabolismo , Células Cultivadas , Células-Tronco/metabolismo , Diferenciação Celular , Proliferação de Células
8.
J Dtsch Dermatol Ges ; 21(12): 1480-1487, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37830438

RESUMO

BACKGROUND: Studies have shown that bullous pemphigoid (BP) occurs in patients with chronic kidney disease (CKD). However, the risk of developing BP in patients with CKD remains inconclusive. OBJECTIVE: To investigate whether CKD increases the risk of BP. METHODS: Participants were recruited from the National Health Insurance Database of Taiwan between 2007 and 2018. Overall, 637,664 newly diagnosed patients with CKD and 637,664 age-, sex-, and comorbidity-matched non-CKD participants were selected. A competing risk model was used to evaluate the risk of development of BP. RESULTS: After adjusting for age, sex, and comorbid diseases in the multivariate model, CKD was a significant risk factor for BP (adjusted hazard ratio [aHR]: 1.29; 95% confidence interval [CI]: 1.17-1.42; p < 0.001). CKD patients were classified into the dialytic or non-dialytic groups and compared to non-CKD participants, and this revealed that patients with dialysis-dependent CKD had the highest risk of BP (aHR 1.75; 95% CI 1.51-2.03), followed by patients with non-dialysis-dependent CKD (aHR 1.20; 95% CI 1.08-1.32). LIMITATIONS: We lacked detailed laboratory data on the severity of CKD. CONCLUSIONS: Compared with individuals without CKD, those with CKD had a 1.3-fold increased risk of BP. Patients with dialysis-dependent CKD had an even higher BP risk (1.8-fold).


Assuntos
Penfigoide Bolhoso , Insuficiência Renal Crônica , Humanos , Estudos de Coortes , Penfigoide Bolhoso/epidemiologia , Penfigoide Bolhoso/etiologia , Incidência , Fatores de Risco , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/complicações
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(9): 901-908, 2023.
Artigo em Chinês | MEDLINE | ID: mdl-37718394

RESUMO

OBJECTIVES: To compare the impact of two types of fat emulsion on clinical outcomes in preterm infants with varying duration of parenteral nutrition (PN). METHODS: Preterm infants meeting the inclusion criteria were randomly assigned to two groups: medium/long-chain triglyceride fat emulsion (referred to as MCT/LCT) group or multi-oil fat emulsion (containing soybean oil, medium-chain triglycerides, olive oil, and fish oil; referred to as SMOF) group. The infants were stratified into groups based on the duration of PN (15-21 days, 22-28 days, and ≥29 days). Clinical characteristics, nutritional status, biochemical indicators, and clinical outcomes were compared between the two groups. RESULTS: Compared with the MCT/LCT group, the SMOF group had lower peak levels of triglyceride during the hospital stay in preterm infants with PN of 15-21 days, 22-28 days, and ≥29 days, respectively (P<0.05). Logistic regression trend analysis showed that with a longer duration of PN, the risk of parenteral nutrition-associated cholestasis (PNAC) and bronchopulmonary dysplasia (BPD) significantly increased in the MCT/LCT group (P<0.05), while the risk of brain injury did not significantly change (P>0.05). In the SMOF group, the risks of PNAC and BPD did not significantly change with a longer duration of PN (P>0.05), but the risk of brain injury significantly decreased (P=0.006). CONCLUSIONS: Compared to MCT/LCT, SMOF have better lipid tolerance. With a longer duration of PN, SMOF does not increase the risks of PNAC and BPD and had a protective effect against brain injury. This suggests that in preterm infants requiring long-term PN, the use of SMOF is superior to MCT/LCT.

10.
Eur J Pediatr ; 181(12): 4167-4174, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36166098

RESUMO

Hypoglycemia is common among neonates and can cause neurological dysfunction. This study aimed to identify the specific time window to perform diffusion-weighted imaging (DWI) for detecting early brain injury in neonatal hypoglycemia and assess the clinical characteristics and neurological outcomes of different patterns of brain injury in neonatal hypoglycemia. We conducted a retrospective analysis of the changes in conventional magnetic resonance imaging (MRI) and DWI at different time points and clinical characteristics in 86 neonates with hypoglycemic brain injury. Among 139 DWI scans, 84 showed injury site hyperintensities within 7 days after hypoglycemia. Thirty-nine scans revealed low DWI and abnormal T1-/T2-weighted imaging signals within 11-23 days after onset, of which 21 showed DWI hyperintensities in the corpus callosum. Abnormal signals were undetected in the second scans of 13 infants within 9-20 days after onset. Vulnerable sites comprised the occipital lobe (98%), splenium of the corpus callosum (60%), and parietal lobe (30%). Compared with focal injury (n = 66), extensive injury (n = 20) had higher involvement of the internal capsule, basal ganglia, and thalamus (P < 0.05); higher incidence of recurrent convulsions, respiratory failure, and coma (P < 0.01); and a higher proportion of death and severe neurodevelopmental impairment (P < 0.05). CONCLUSIONS: Neonatal hypoglycemic brain injury was most common in the occipital lobes. Severe clinical symptoms were significantly associated with extensive brain injury involving the internal capsule, basal ganglia, and thalamus, which could be attributed to hypoxia-ischemia and lead to a poor prognosis. WHAT IS KNOWN: • There is no clear neurological safe threshold for hypoglycemia in neonates. Studies suggest that symptomatic hypoglycemia can be related to brain injury. WHAT IS NEW: • Severe clinical symptoms are significantly associated with extensive brain injury on MRI scans. Extensive brain injuries involving the internal capsule, basal ganglia, and thalamus, which could be due to associated hypoxia-ischemia and lead to a poor prognosis.


Assuntos
Lesões Encefálicas , Hipoglicemia , Hipóxia-Isquemia Encefálica , Lactente , Recém-Nascido , Humanos , Hipoglicemiantes , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Hipoglicemia/etiologia , Hipoglicemia/complicações , Imagem de Difusão por Ressonância Magnética/métodos , Lesões Encefálicas/etiologia , Lesões Encefálicas/complicações , Hipóxia/complicações , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/complicações
11.
Int J Mol Sci ; 23(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35563561

RESUMO

There is growing evidence that the mechanical properties of extracellular matrices (ECMs), including elasticity and stress-relaxation, greatly influence the function and form of the residing cells. However, the effects of elasticity and stress-relaxation are often correlated, making the study of the effect of stress-relaxation on cellular behaviors difficult. Here, we designed a hybrid network hydrogel with a controllable stress-relaxation gradient and a constant elasticity. The hydrogel is crosslinked by covalent bonds and dynamic peptide-metal ion coordination interactions. The stress-relaxation gradient is controlled by spatially controlling the coordination and covalent crosslinker ratios. The different parts of the hydrogel exhibit distinct stress-relaxation amplitudes but the have same stress-relaxation timescale. Based on this hydrogel, we investigate the influence of hydrogel stress-relaxation on cell spreading. Our results show that the spreading of cells is suppressed at an increasing stress-relaxation amplitude with a fixed elasticity and stress-relaxation timescale. Our study provides a universal route to tune the stress-relaxation of hydrogels without changing their components and elasticity, which may be valuable for systematic investigations of the stress-relaxation gradient in cell cultures and organoid constructions.


Assuntos
Técnicas de Cultura de Células , Hidrogéis , Técnicas de Cultura de Células/métodos , Elasticidade , Matriz Extracelular , Hidrogéis/química
12.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077375

RESUMO

Glue-type bio-adhesives are in high demand for many applications, including hemostasis, wound closure, and integration of bioelectronic devices, due to their injectable ability and in situ adhesion. However, most glue-type bio-adhesives cannot be used for short-term tissue adhesion due to their weak instant cohesion. Here, we show a novel glue-type bio-adhesive based on the phase separation of proteins and polysaccharides by functionalizing polysaccharides with dopa. The bio-adhesive exhibits increased adhesion performance and enhanced phase separation behaviors. Because of the cohesion from phase separation and adhesion from dopa, the bio-adhesive shows excellent instant and long-term adhesion performance for both organic and inorganic substrates. The long-term adhesion strength of the bio-glue on wet tissues reached 1.48 MPa (shear strength), while the interfacial toughness reached ~880 J m-2. Due to the unique phase separation behaviors, the bio-glue can even work normally in aqueous environments. At last, the feasibility of this glue-type bio-adhesive in the adhesion of various visceral tissues in vitro was demonstrated to have excellent biocompatibility. Given the convenience of application, biocompatibility, and robust bio-adhesion, we anticipate the bio-glue may find broad biomedical and clinical applications.


Assuntos
Adesivos , Di-Hidroxifenilalanina , Polissacarídeos
13.
Angew Chem Int Ed Engl ; 61(25): e202201765, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35419931

RESUMO

Biological load-bearing tissues are strong, tough, and recoverable under periodic mechanical loads. However, such features have rarely been achieved simultaneously in the same synthetic hydrogels. Here, we use a force-coupled enzymatic reaction to tune a strong covalent peptide linkage to a reversible bond. Based on this concept we engineered double network hydrogels that combine high mechanical strength and reversible mechanical recovery in the same hydrogels. Specifically, we found that a peptide ligase, sortase A, can promote the proteolysis of peptides under force. The peptide bond can be re-ligated by the same enzyme in the absence of force. This allows the sacrificial network in the double-network hydrogels to be ruptured and rebuilt reversibly. Our results demonstrate a general approach for precisely controlling the mechanical and dynamic properties of hydrogels at the molecular level.


Assuntos
Hidrogéis , Fenômenos Mecânicos , Hidrogéis/química , Peptídeos
14.
J Child Sex Abus ; 30(5): 524-545, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33719924

RESUMO

This study investigated how the news media in China - a country influenced by collectivism, authoritarianism, and Confucianism - portrayed child sexual abuse to the public over the past decade. A content analysis of 501 newspaper articles published over that time period revealed how news portrayals of child sexual abuse changed following notable abuse cases and refinements in relevant laws in China. The results indicated that media attention to child sexual abuse increased dramatically after 2013, and a trend of shaping child sexual abuse as a social problem began in 2015. This study also found an interesting cultural difference in the application of framing theory. The Chinese news stories of child sexual abuse were more likely to present individual cause frames but societal solution frames. This apparent inconsistency was not seen in previous research with U.S. media and may be attributable to a cultural preference for victim blame and collective solutions. The findings provide insights into news portrayals of child sexual abuse in a developing society. In addition, this study points out potential problems in Chinese news reports on child sexual abuse and offers suggestions for journalists and advocates for children.


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Criança , China , Humanos , Meios de Comunicação de Massa , Percepção Social
15.
Angew Chem Int Ed Engl ; 60(41): 22332-22338, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34008254

RESUMO

Depending on the dynamics of the crosslinks, polymer networks can have distinct bulk mechanical behaviors, from viscous liquids to tough solids. Here, by means of designing a crosslink with variable molecular dynamics, we show the control of viscoelasticity of polymer networks in a broad range quantitatively. The hexanoate-isoquinoline@cucurbit[7]uril (HIQ@CB[7]) crosslink exhibits in a combination of protonated and deprotonated states of similar association affinity but distinct molecular dynamics. The molecular property of this crosslink is contributed by linear combination of the parameters at the two states, which is precisely tuned by pH. Using this crosslink, we achieve the quantitative control of viscoelasticity of quasi-ideal networks in 5 orders of magnitude, and we show the reversible control of mechanical response, such as stiffness, strength and extensibility, of tough random polymer networks. This strategy offers a way to tailor the mechanical properties of polymer networks at the molecular level and paves the way for engineering "smart" responsive materials.

16.
Prev Med ; 141: 106288, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33091414

RESUMO

Government trust is known to be associated with preventive practices during pandemics, but few studies have explored the roles of knowledge and negative emotion in conditioning the relationship between trust and preventive behaviors. The aim of this study was to explore the roles of knowledge and negative emotion in conditioning the relationship between trust and preventive measures during the COVID-19 pandemic in China. Data from a cross-sectional survey of 3000 Chinese adults [mean (SD) age 36.93 (12.11) years; 52.4% male], conducted using quota-sampling method (March 2-2020 to March 23-2020), were analyzed. Overall, respondents performed recommended preventive measures more frequently (3.21 out of 4) than excessive preventive measures (2.11 out of 4). Government trust was positively associated with both officially recommended (b = 0.12; 95%CI = 0.18, 0.25) and excessive preventive behaviors (b = 0.07; 95%CI = 0.03, 0.10). The positive relationship between trust and excessive preventive behaviors was found to be statistically significant only among those with low levels of COVID-19 knowledge. Officially recommended preventive behavior is most likely to happen when there is a combination of high levels of government trust and low levels of negative emotion. Therefore, government trust increases both official and excessive (sometimes unscientific) preventive behaviors. Interventions shall aim to enhance people's COVID-19 knowledge and to reduce negative emotions.


Assuntos
COVID-19/prevenção & controle , COVID-19/psicologia , Programas Governamentais , Comportamentos Relacionados com a Saúde , Pandemias/prevenção & controle , Medicina Preventiva , Confiança/psicologia , Adulto , China , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Inquéritos e Questionários , Adulto Jovem
17.
J Am Chem Soc ; 141(48): 19171-19177, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31721571

RESUMO

Cellular genes that are functionally related to each other are usually confined in specialized subcellular compartments for efficient biochemical reactions. Construction of spatially controlled biosynthetic systems will facilitate the study of biological design principles. Herein, we fabricated a gene circuit compartment by coanchoring two function-related genes on surface of gold nanoparticles and investigated the compartment effect on cascade gene expression in a cell-free system. The gene circuit consisted of a T7 RNA polymerase (T7 RNAP) expression cassette as regulatory gene and a fluorescent protein expression cassette as regulated reporter gene. Both the expression cassettes were attached on a Y-shaped DNA nanostructure whose other two branches were mercapto-modified in order to steadily anchor the gene expression cassettes on the surface of gold nanoparticles. Experimental results demonstrated that both the yield and initial expression rate of the fluorescent reporter protein in the gene circuit compartment system were enhanced compared with those in free gene circuit system. Mechanism investigation revealed that the gene circuit compartment on nanoparticle made the regulatory gene and regulated reporter gene spatially proximal at nanoscale, thus effectively improving the transfer efficiency of the regulatory proteins (T7 RNAP) from regulatory genes to the regulated reporter genes in the compartments, and consequently, the biochemical reaction efficiency was significantly increased. This work not only provided a simplified model for rational molecular programming of genes circuit compartments on nanointerface but also presented implications for the cellular structure-function relationship.


Assuntos
Bacteriófago T7/enzimologia , RNA Polimerases Dirigidas por DNA/genética , Redes Reguladoras de Genes , Ouro/química , Proteínas de Fluorescência Verde/genética , Nanopartículas Metálicas/química , Proteínas Virais/genética , Bacteriófago T7/genética , Expressão Gênica , Genes Reporter
18.
Lab Invest ; 99(11): 1714-1727, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30683901

RESUMO

Ocular anterior segment dysgenesis (ASD) is a failure of normal development of anterior structures of the eye, leading to lens opacification. The underlying mechanisms relating to ASD are still unclear. Previous studies have implicated transcriptional factor muscle segment homeobox 2 (Msx2) in ASD. In this study, we used Msx2 conditional knockout (CKO) mice as a model and found that Msx2 deficiency in surface ectoderm induced ASD. Loss of Msx2 function specifically affected lens development, while other eye structures were not significantly affected. Multiple lines of evidence show that calcium signaling pathways are involved in this pathogenesis. Our study demonstrates that Msx2 plays an essential role in lens development by activating a yet undetermined calcium signaling pathway.


Assuntos
Anormalidades do Olho/genética , Anormalidades do Olho/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Cristalino/metabolismo , Animais , Apoptose , Sinalização do Cálcio , Proliferação de Células , Cristalinas/genética , Ectoderma/anormalidades , Ectoderma/embriologia , Ectoderma/metabolismo , Anormalidades do Olho/embriologia , Feminino , Expressão Gênica , Técnicas de Inativação de Genes , Cristalino/anormalidades , Cristalino/embriologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidez
19.
Langmuir ; 35(17): 5931-5936, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30955336

RESUMO

Cellular physical microenvironment such as crowding shows great influence on enzymatic reactions. Herein, we report a new finding that saccharides with low molecular weight create an effective crowding microenvironment for gene expression in cell-free protein synthesis, which provides valuable implications for living systems. Four saccharides including sorbose, galactose, sucrose, and cellobiose are screened out as effective crowders. At a low concentration range of saccharides, both the mRNA and protein amounts present an upward trend with the concentration increment of saccharides; when the concentrations exceed a critical value, the mRNA and protein amounts decrease. A mechanism is proposed that at low concentrations of saccharides, the effective concentrations of reactants increase due to the coexistence of crowders and reactants in a finite volume; when the concentrations exceed a critical value, the molecular diffusion of reactants is dominantly restricted due to the increased viscosity. Our finding opens a new view that saccharides with low molecular weight could be crowders and provides a new insight that substances with low molecular weight in cells would produce a crowding effect on biochemical reactions in living systems.


Assuntos
Expressão Gênica/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Açúcares/química , Difusão , Escherichia coli/química , Proteínas de Fluorescência Verde/metabolismo , Peso Molecular , RNA Mensageiro/metabolismo , Viscosidade
20.
Soft Matter ; 15(22): 4423-4427, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31106324

RESUMO

The dynamic mechanical response of hydrogels is correlated with the intrinsic dynamics of the crosslinkers. Our experiments and theory show that polymer network structures can also affect the dynamic response of hydrogels by transducing swelling forces to the crosslinkers. Our results suggest a novel route to engineer complex time-dependent mechanical properties of soft materials for biomedical applications.

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