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1.
Biomacromolecules ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39321123

RESUMO

Cellulose has been widely used in papermaking, textile, and chemical industries due to its diverse sources, environmental friendliness, and renewability. Recently, much more attention has been paid to converting cellulose into high-value-added products. Therefore, the extraction of nanocellulose, the dissolution of cellulose, and their applications are some of the most important research topics currently. However, cellulose's dense hydrogen bond network poses challenges for efficient extraction and dissolution, limiting its potential for functional material development. This review discusses the mechanisms of hydrogen bond disruption and weak interactions during nanocellulose extraction and cellulose dissolution. Key challenges and future research directions are highlighted, emphasizing developing efficient, ecofriendly, and cost-effective methods. Additionally, this review provides theoretical insights for constructing high-performance cellulose-based materials.

2.
Oncol Res ; 32(10): 1637-1648, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39308524

RESUMO

Background: Metformin has pleiotropic effects beyond glucose reduction, including tumor inhibition and immune regulation. It enhanced the anti-tumor effects of programmed cell death protein 1 (PD-1) inhibitors in serine/threonine kinase 11 (STK11) mutant non-small cell lung cancer (NSCLC) through an axis inhibition protein 1 (AXIN1)-dependent manner. However, the alterations of tumor metabolism and metabolites upon metformin administration remain unclear. Methods: We performed untargeted metabolomics using liquid chromatography (LC)-mass spectrometry (MS)/MS system and conducted cell experiments to verify the results of bioinformatics analysis. Results: According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database, most metabolites were annotated into metabolism, including nucleotide metabolism. Next, the differentially expressed metabolites in H460 (refers to H460 cells), H460_met (refers to metformin-treated H460 cells), and H460_KO_met (refers to metformin-treated Axin1 -/- H460 cells) were distributed into six clusters based on expression patterns. The clusters with a reversed expression pattern upon metformin treatment were selected for further analysis. We screened out metabolic pathways through KEGG pathway enrichment analysis and found that multiple nucleotide metabolites enriched in this pathway were upregulated. Furthermore, these metabolites enhanced the cytotoxicity of activated T cells on H460 cells in vitro and can activate the stimulator of the interferon genes (STING) pathway independently of AXIN1. Conclusion: Relying on AXIN1, metformin upregulated multiple nucleotide metabolites which promoted STING signaling and the killing of activated T cells in STK11 mutant NSCLC, indicating a potential immunotherapeutic strategy for STK11 mutant NSCLC.


Assuntos
Quinases Proteína-Quinases Ativadas por AMP , Proteína Axina , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Metformina , Mutação , Nucleotídeos , Proteínas Serina-Treonina Quinases , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metformina/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteína Axina/genética , Proteína Axina/metabolismo , Nucleotídeos/metabolismo , Linhagem Celular Tumoral , Regulação para Cima , Metabolômica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
3.
Exp Ther Med ; 28(5): 427, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39301250

RESUMO

The gut microbiota refers to the diverse bacterial community residing in the gastrointestinal tract. Recent data indicate a strong correlation between alterations in the gut microbiota composition and the onset of various diseases, notably cardiovascular disorders. Evidence suggests the gut-cardiovascular axis signaling molecules released by the gut microbiota play a pivotal role in regulation. This review systematically delineates the association between dysbiosis of the gut microbiota and prevalent cardiovascular diseases, including atherosclerosis, hypertension, myocardial infarction and heart failure. Furthermore, it provides an overview of the putative pathogenic mechanisms by which dysbiosis in the gut microbiota contributes to the progression of cardiovascular ailments. The potential modulation of gut microbiota as a preventive strategy against cardiovascular diseases through dietary interventions, antibiotic therapies and probiotic supplementation is also explored and discussed within the present study.

4.
Mar Life Sci Technol ; 6(3): 535-546, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39219686

RESUMO

Eczema is a common chronic dermatological disease. Conventional treatments exhibit limited efficacy due to fast drug release resulting in short-term relief. Development of a new treatment strategy that enables sustained drug release and long-term maintenance on the skin surface is necessary. A self-adhesive swelling microneedle patch (SDSMNs) was designed and constructed using a two-step casting method. The adhesive substrate was prepared by blending gelatin and dopamine via oxidation of NaIO4, so it could adhere onto the skin surface as well as withstand repeated bending movement without detachment. The swelling needles were fabricated using polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), which could swell by absorbing interstitial fluid and release the drug in a controlled manner. SDSMNs also showed desirable antibacterial activities toward E. coli and S. aureus. The adhesive microneedles loaded with matrine (MAT-SDSMNs), an anti-inflammatory Chinese medicine, dramatically relieved eczema symptoms through IL-17 mediated inflammation responses. The use of MAT-SDSMNs significantly decreased the infiltration of inflammation cells and level of inflammatory cytokines, reduced the skin thickness, and increased collagen deposition fraction compared with conventional ointment or subcutaneous injection. The results suggested that MAT-SDSMNs can improve eczema treatment by regulating the local inflammatory microenvironment, providing a simple, self-administered sustainable strategy for eczema treatment. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-024-00235-z.

5.
Front Neurol ; 15: 1419017, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39220736

RESUMO

Background: Many studies have explored the risk factors associated with cognitive impairment in patients with Type 2 diabetes mellitus (T2DM). However, research on determining the optimal threshold for these risk factors and comparative studies on the therapeutic effects of insulin and metformin is limited. This study aims to establish the optimal threshold for cognitive impairment risk factors in T2DM patients and compare the efficacy of insulin and metformin in treating mild cognitive impairment (MCI). Methods: A total of 308 patients with T2DM were included. The optimal threshold for cognitive impairment risk factors was determined using receiver operating characteristic curve and binary logistic regression models. MCI patients were divided into three groups: insulin, metformin, and insulin with metformin. The treatment effect was evaluated after a 6-month follow-up. Results: The study identified several factors that influenced cognitive function in T2DM patients, including female gender, duration of diabetes >13.50 years, years of education >7.50 years, and serum sodium level > 141.90 mmol/L. Metformin and insulin with metformin showed superior therapeutic effects compared to insulin alone, but no difference was observed between metformin and combination therapy. Conclusion: Special attention should be given to female and those with diabetes duration >13.50 years, as well as to individuals with educational level ≤ 7.50 years and serum sodium concentration ≤ 141.90 mmol/L. Metformin and insulin with metformin effectively improve MCI in patients with T2DM and outperform insulin monotherapy. The efficacy of metformin and combination therapy was found to be comparable.

6.
Carbohydr Polym ; 345: 122566, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227121

RESUMO

Flexible electronic sensing and energy storage technology impose heightened demands on the mechanical and stable properties of gel electrolyte materials. Lignocellulosic nanofiber (LCNF) present a promising avenue for improving the properties of electrolyte networks and mechanical strength. In this study, LCNF derived from hemp fibers was prepared using lactic acid/choline chloride deep eutectic solvent (DES) through a combination of cooking and colloid mill mechanical treatment to achieve nanocellulose with a high aspect ratio and uniform dimensions. The outcomes demonstrated that LCNF, a width of below 20 nm and a length of over 5 µm, can be effectively produced through the DES cooking pretreatment in conjunction with colloid mill mechanical treatment. Meanwhile, DES lignin possessed a purity of ∼90 % and was obtained as a by-product. Subsequently, the as-prepared LCNF was integrated as a nanofiller into gel electrolyte. Ag-L NPs/LCNF/DES/PAA exhibited dense porous structures and showcased exceptional properties, including a high conductivity exceeding 10 mS/cm and remarkable adhesion strength surpassing 100 KPa. The presence of LCNF allowed Ag-L NPs/LCNF/DES/PAA to achieve strains above 1000 % and compression properties over 1000 KPa. The supercapacitor based on this assembly had a high specific capacitance of 271 F g-1 at 0.5 A g-1), along with an impressive capacity retention rate reaching ∼100 % after 3000 cycles. This investigation offers valuable insights into the utilization of lignocellulosic multi-component approaches in the development of flexible electronic devices.

7.
Crit Rev Biotechnol ; : 1-16, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266251

RESUMO

Geraniol, an acyclic monoterpene alcohol, has significant potential applications in various fields, including: food, cosmetics, biofuels, and pharmaceuticals. However, the current sources of geraniol mainly include plant tissue extraction or chemical synthesis, which are unsustainable and suffer severely from high energy consumption and severe environmental problems. The process of microbial production of geraniol has recently undergone vigorous development. Particularly, the sustainable construction of recombinant Escherichia coli (13.2 g/L) and Saccharomyces cerevisiae (5.5 g/L) laid a solid foundation for the microbial production of geraniol. In this review, recent advances in the development of geraniol-producing strains, including: metabolic pathway construction, key enzyme improvement, genetic modification strategies, and cytotoxicity alleviation, are critically summarized. Furthermore, the key challenges in scaling up geraniol production and future perspectives for the development of robust geraniol-producing strains are suggested. This review provides theoretical guidance for the industrial production of geraniol using microbial cell factories.

8.
BMC Infect Dis ; 24(1): 983, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285384

RESUMO

To assess the safety of varicella vaccine (VarV) by conducting post-marketing surveillance on adverse events following immunization (AEFI) in Jiangsu Province, China. METHODS: We utilized the AEFI Information System of mainland China to monitor and categorize adverse reactions associated with VarV. RESULTS: The incidence rate of AEFI was significantly higher after the first dose (48.79/100,000 doses) compared to the second dose (45.18/100,000 doses) (χ2 = 4.63, P = 0.031). Regional variations in AEFI incidence were observed within Jiangsu Province. Common reactions comprised 90.96% of AEFIs, while rare reactions and coincidental events accounted for 6.59% and 0.51%, respectively. Notably, there were no adverse events linked to vaccine quality, program errors, psychogenic reactions, or fatalities. Over 96% of AEFIs occurred within three days of VarV administration, with redness at the injection site (2.6 cm to 5 cm in diameter) being the most frequently observed symptom. CONCLUSION: VarV demonstrates a commendable safety profile. Although there was a slight increase in AEFI incidence between 2022 and 2023, common vaccine reactions were predominantly observed, and the rates of rare reactions remained very low.


Assuntos
Vacina contra Varicela , Varicela , Humanos , Vacina contra Varicela/efeitos adversos , Vacina contra Varicela/administração & dosagem , China/epidemiologia , Masculino , Feminino , Lactente , Criança , Pré-Escolar , Incidência , Varicela/prevenção & controle , Varicela/epidemiologia , Vigilância de Produtos Comercializados , Adolescente , Adulto , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Vacinação/efeitos adversos , Adulto Jovem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Pessoa de Meia-Idade
9.
ACS Appl Mater Interfaces ; 16(36): 48386-48394, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39205497

RESUMO

Melioration of the through-plane thermal conductivity (TC) of thermal interface materials (TIMs) is a sore need for efficient heat dissipation to handle an overheating concern of high-power-density electronics. Herein, we constructed a snail shell-like thermal conductive framework to facilitate vertical heat conduction in TIMs. With inspiration from spirally growing calcium carbonate platelets of snail shells, a facile double-microrod-assisted curliness method was developed to spirally coil boron nitride nanosheet (BNNS)/aramid nanofiber (ANF) laminates where interconnected BNNSs lie along the horizontal plane. Thus, vertical alignment of BNNSs in the resultant TIM was achieved, exhibiting a through-plane TC enhancement of ∼100% compared to the counterpart with randomly distributed BNNSs at the same BNNS addition (50 wt %). The Foygel's nonlinear model revealed that this unique snail shell-like BNNS framework reduced interfacial thermal resistance by 4 orders of magnitude. Our TIM showed superior interfacial thermal dissipation efficiency, leading to a temperature reduction of 42.6 °C for the LED chip compared to the aforementioned counterpart. Our work paves a valuable way for fabricating high-performance TIMs to ensure reliable operation of electrical devices.

10.
Angew Chem Int Ed Engl ; : e202408359, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106109

RESUMO

Direct aromatization of cyclohexanones to synthesize substituted phenols represents a significant challenge in modern synthetic chemistry. Herein, we describe a novel ene-reductase (TsER) catalytic system that converts substituted cyclohexanones into the corresponding phenols. This process involves the successive dehydrogenation of two saturated carbon-carbon bonds within the six-membered ring of cyclohexanones and utilizes molecular oxygen to drive the reaction cycle. It demonstrates a versatile and efficient approach for the synthesis of substituted phenols, providing a valuable complement to existing chemical methodologies.

11.
J Environ Manage ; 367: 122076, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39111014

RESUMO

Rapid urbanization has highlighted ecological problems in the metropolitan area, with increasing landscape fragmentation and severe threats to ecosystem health (EH). Studying the spatio-temporal coupled relationship between landscape pattern and EH and its response to urbanization in the Fuzhou metropolitan area (FMA) can provide scientific reference for its long-term development planning. We examined the coupled relationship between landscape pattern and EH and its driving mechanism in the FMA at grid and township scales to address the gap. The results show that landscape heterogeneity, diversity, and dispersion are gradually increasing, and EH is rising progressively in the FMA from 2000 to 2020. The spatial distribution of landscape pattern indices and EH indicators showed a "high in the south and low in the north" trend. During the study period, the coupled relationship between landscape patterns and EH was increasingly powerful but with remarkable spatial heterogeneity. The study also found an inverted U-shaped relationship between urbanization and coupled relationships. Ecological landscapes' heterogeneity, diversity, and connectivity in low-urbanization areas are conducive to EH. The opposite is true for high-urbanization areas. This study provides a valuable reference for optimizing landscape planning and ecological management in metropolitan areas.


Assuntos
Ecossistema , Urbanização , Conservação dos Recursos Naturais
12.
Angew Chem Int Ed Engl ; : e202412862, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140466

RESUMO

In the field of biocatalysis, discovering novel reactivity from known enzymes has been a longstanding challenge. Fatty acid photo-decarboxylase from Chlorella variabilis (CvFAP) has drawn considerable attention as a promising photoenzyme with potential green chemistry applications; however, its non-natural reactivity has rarely been exploited to date. Herein we report a non-natural reductive dehalogenation (deacetoxylation) reactivity of CvFAP inspired by its natural oxidative decarboxylation process, enabling the  stereoselective synthesis of a series of chiral α-substituted tetralones with high yields (up to 99%) and e.r. values (up to 99:1). Mechanistic studies demonstrated that the native photoenzyme catalyzed the reductive dehalogenation via a novel mechanism involving oxidized state (FADox) / semiquinone state (FADsq) redox pair and an electron transfer (ET)/proton transfer (PT) process of radical termination, distinct from the previous reports. To our knowledge, this study represents a new example of CvFAP promiscuity, and thus expands the reactivity repertoire of CvFAP and highlights the versatility of CvFAP in asymmetric synthesis.

13.
Int J Biol Macromol ; 278(Pt 4): 134752, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39214837

RESUMO

Three-dimensional bioprinting leverages computer-aided design to construct tissues and organs with specialized bioinks. A notable biomaterial for this purpose is chitosan, a natural polysaccharide sourced from crustacean exoskeletons. Chitosan's biocompatibility, biodegradability, non-toxicity, and ability to promote cell adhesion and proliferation make it an excellent component for bioinks. Initially, the rheological properties of chitosan presented challenges for its use in bioprinting. Enhancements in its printability and stability were achieved by integrating it with other natural or synthetic polymers, facilitating its successful application in bioprinting. Chitosan-based bioinks are particularly promising for controlled drug delivery. Incorporating pharmaceuticals directly into the bioink enables the printed structures to serve as localized, sustained-release systems. This approach offers multiple advantages, including precise drug delivery to targeted disease sites, increased therapeutic efficiency, and reduced systemic side effects. Moreover, bioprinting allows for the customization of drug delivery mechanisms to meet individual patient requirements. Although there have been considerable advancements, the use of chitosan-based bioinks in drug delivery is still an emerging field. This review highlights chitosan's essential role in both systemic and localized drug delivery, underscoring its significance and discussing ongoing trends in its application for pharmaceutical purposes.


Assuntos
Bioimpressão , Quitosana , Sistemas de Liberação de Medicamentos , Impressão Tridimensional , Quitosana/química , Bioimpressão/métodos , Humanos , Materiais Biocompatíveis/química , Animais , Tinta , Engenharia Tecidual/métodos
14.
Talanta ; 280: 126681, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142128

RESUMO

Mildewed tobacco leaves seriously impact on cigarette product quality and pose a health risk to person. However, early moldy tobacco leaves are hardly found by naked eyes in the workshop. In this work, we self-assemble AuAg nanoalloys on silicon wafers to construct Si/AuAg chips. The headspace-surface enhanced Raman scattering (SERS) protocol is developed to monitor volatile 1,2-dichloro-3-methoxybenzene (2,3-DCA) and 2,4,6-trichloroanisole (2,4,6-TCA) released from postharvest tobacco. Consequently, the visualization of the SERS peak at 1592 cm-1 assigned to ν(CC) after headspace collection for 10 min and the SERS intensity ratio of 1054 and 1035 cm-1 from 2,3-DCA and 2,4,6-TCA less than 0.5 could be used as indicators to predict early moldy tobacco. Additionally, with headspace collection time prolonging to 2 h, a SERS band at 682 cm-1 due to ν(CCl) of 2,4,6-TCA occurs, confirming the mildew of leaves. The headspace-SERS protocol paves a path for rapid and on-site inspection of the quality of tobacco leaves and cigarettes during storage with a portable Raman system.


Assuntos
Ouro , Nicotiana , Folhas de Planta , Prata , Análise Espectral Raman , Folhas de Planta/química , Nicotiana/química , Análise Espectral Raman/métodos , Prata/química , Ouro/química , Anisóis/análise , Anisóis/química , Nanopartículas Metálicas/química , Silício/química , Doenças das Plantas/microbiologia
15.
Front Oncol ; 14: 1325987, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988713

RESUMO

Objective: To investigate the feasibility and evaluate the safety and effectiveness of Computed Tomography (CT) guided125I radioactive particle implantation for treating lymph node metastases in radioiodine-refractory differentiated thyroid cancer (RAIR-DTC). To verify the accuracy of the computerized three-dimensional treatment planning system (TPS) in treating lymph node metastasis using125I particle implantation at the dosimetric level. Methods: A retrospective analysis was conducted on 42 patients with RAIR-DTC and lymph node metastases who were admitted to the General Hospital of the Northern Theater Command between December 2016 and January 2019. During this analysis, physicians utilized preoperative CT images to design an intraoperative plan using TPS. The dosimetric parameters of the postoperative plan were then compared to the preoperative plan. Additionally, this study examined the changes in tumor size and tumor-related marker Thyroglobulin (Tg) values in patients at 2, 6, and 12 months after the operation. Results: The number of125I radioactive particles implanted in 42 patients was 226, with an average of 14.5 (range 2.0-30.0) particles implanted per lesion. The local remission rates were 97.62% (41/42), 88.10% (37/42), and 85.71% (36/42) at 2, 6, and 12 months postoperatively, respectively. The volume of the lesions was (4.44 ± 1.57) cm3, (4.20 ± 1.70) cm3, and (4.23 ± 1.77) cm3at 2, 6, and 12 months after treatment, respectively, which significantly decreased from the preoperative baseline level of (6.87 ± 1.67) cm3(t-values: 9.466, 9.923, 7.566, all P<0.05). The Tg levels were 15.95 (5.45, 73.93) µg/L, 8.90 (2.20, 39.21) µg/L, and 6.00 (1.93, 14.18) µg/L at 2, 6, and 12 months after treatment, respectively, which were significantly lower than the preoperative baseline levels of 53.50 (20.94, 222.92) µg/L (Z values: -5.258, -5.009, -4.987, all P < 0.001). Postoperatively, Delivered to 90% of the GTV(D90) was slightly lower than the prescribed dose in 95.23% (40/42) of patients, but the difference was not statistically significant [(12,378.8 ± 3,182.0), (12,497.8 ± 1,686.4) cGy; t=0.251, P>0.05], and postoperative dose parameters delivered to 100% of the gross tumor volume (GTV)(D100) (6,881.5 ± 1,381.8) cGy, the volume percentages of GTV receiving 150% of the prescribed dose(V150) (58.5 ± 18.40)%) were lower than the preoperative plan D100 (8,085.8 ± 2,330.0) cGy, V150 (66.5 ± 17.70)%; t-value=8.913 and 3.032, both P<0.05; the remaining indicators were not significantly different from the preoperative plan (the differences in the number of implanted particles, Planning Target Volume(PTV), the volume percentages of GTV receiving 100% of the prescribed dose(V100), Homogeneity Index(HI)were not statistically significant (t/Z = -0.593, -1.604, 1.493, -0.663, all P>0.05). Conclusion: Referring to the TPS preoperative plan, the125I particle implantation therapy for RAIR-DTC lymph node metastasis can achieve the expected dose distribution, ensuring precise short-term local tumor control efficacy.

16.
Sensors (Basel) ; 24(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000962

RESUMO

As one of the important lakes in the "One Lake and Two Seas" of the Inner Mongolia Autonomous Region, the monitoring of water quality in Lake Daihai has attracted increasing attention, and the concentration of chlorophyll-a directly affects the water quality, making the monitoring of chlorophyll-a concentration in Lake Daihai particularly crucial. Traditional methods of monitoring chlorophyll-a concentration are not only inefficient but also require significant human and material resources. Remote sensing technology has the advantages of wide coverage and short update cycles. For lakes such as Daihai with a high salinity content, salinity is considered a key factor when inverting the concentration of chlorophyll-a. In this study, machine learning models, including model stacking from ensemble learning, a ridge regression model, and a random forest model, were constructed. After comparing the training accuracy of the three models on Zhuhai-1 satellite data, the random forest model, which had the highest accuracy, was selected as the final training model. By comparing the accuracy changes before and after adding salinity factors to the random forest model, a high-precision model for inverting chlorophyll-a concentration in hypersaline lakes was obtained. The research results show that, without considering the salinity factor, the root mean square error (RMSE) of the model was 0.056, and the coefficient of determination (R2) was 0.64, indicating moderate model performance. After adding the salinity factor, the model accuracy significantly improved: the RMSE decreased to 0.047, and the R2 increased to 0.92. This study provides a solid basis for the application of remote sensing technology in hypersaline aquatic environments, confirming the importance of considering salinity when estimating chlorophyll-a concentration in hypersaline waters. This research helps us gain a deeper understanding of the water quality and ecosystem evolution in Daihai Lake.

17.
Behav Sci (Basel) ; 14(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39062383

RESUMO

This study explores the learning effects of color cues in video lectures and their underlying mechanisms. With the rapid growth of online education, lifelong learning, and blended learning, video lectures have become integral to teaching and learning. Color, a crucial element in visual design, directs attention, organizes content, and integrates information. Evaluating 78 college students, we assessed learning performance by comparing video content with no-color, single-color, and multi-color cues using eye-tracking technology and cognitive load scales. Results indicate that students viewing videos with color cues demonstrated better retention and transfer test performance, while absence or excess of color cues increased cognitive load. These findings have practical implications for video producers and provide a theoretical foundation for enhancing learners' viewing experience and overall effectiveness. This study not only offers an in-depth analysis of color cue utilization in video lectures, highlighting their positive impact on learning outcomes but also introduces fresh perspectives for educational technology and cognitive psychology research. Future investigations should consider color cue effects in diverse cultural contexts and subject areas, exploring varied strategies to optimize the learning experience.

18.
Protein J ; 43(4): 683-696, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39068631

RESUMO

A recent study showed that just one point mutation F33 to Y in the complementarity-determining region 1 of heavy chain (H-CDR1) could lead to the auto-antibody losing its DNA binding ability. However, the potential molecular mechanisms have not been well elucidated. In this study, we investigated how the antibody lost the DNA binding ability caused by mutation F33 to Y in the H-CDR1. We found that the electrostatic force was not the primary driving force for the interaction between anti-DNA antibodies and the antigen single strand DNA (ssDNA), and that the H-CDR2 largely contributed to the binding of antigen ssDNA, even larger than H-CDR1. The H-F33Y mutation could increase the hydrogen-bond interaction but impair the pi-pi stacking interaction between the antibody and ssDNA. We further found that F33H, W98H and Y95L in the wiletype antibody could form the stable pi-pi stacking interaction with the nucleotide bases of ssDNA. However, the Y33 in mutant could not form the parallel sandwich pi-pi stacking interaction with the ssDNA. To further confirm the importance of pi-pi stacking, the wildtype antibody and the mutants (F33YH, F33AH, W98AH and Y95AL) were experimentally expressed in CHO cells and purified, and the results from ELISA clearly showed that all the mutants lost the ssDNA binding ability. Taken together, our findings may not only deepen the understanding of the underlying interaction mechanism between autoantibody and antigen, but also broad implications in the field of antibody engineer.


Assuntos
Regiões Determinantes de Complementaridade , DNA de Cadeia Simples , Mutação Puntual , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/química , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/química , Animais , Cricetulus , Células CHO , Autoanticorpos/genética , Autoanticorpos/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/química
19.
BMC Infect Dis ; 24(1): 718, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039455

RESUMO

Mumps is a vaccine-preventable disease with high contagious capability. Its incidence declined rapidly since one dose of mumps vaccine was introduced into Expanded Program of Immunization (EPI) in 2008 in China. Nonetheless, the outbreaks of mumps remain frequent in China. Here we aim to assess herd immunity level followed by one-dose mumps ingredient vaccine and to elucidate the genetic characteristics of mumps viruses circulating in the post vaccine era in Jiangsu province of China. The complete sequences of mumps virus small hydrophobic(SH) gene were amplified and sequenced; coalescent-based Bayesian method was used to perform phylogenetic analysis with BEAST 1.84 software. Commercially available indirect enzyme-linked immune-sorbent IgG assay was used for the quantitative detection of IgG antibody against mumps virus. Our results show that genotype F was the predominant mumps viruses and belonged to indigenous spread, and most of Jiangsu sequences clustered together and formed a monophyly. The prevalence of mumps reached a peak in 2012 and subsequently declined, which presented an obvious different trajectory with virus circulating in other regions of China. The gene diversity of viruses circulating in Jiangsu province was far less than those in China. The antibody prevalence reached 70.42% in the general population during 2018 to 2020. The rising trend of antibody level was also observed. Although mumps antibody prevalence does not reach expected level, mumps virus faces higher pressure in Jiangsu province than the whole of China. To reduce further the prevalence of mumps viruses, two doses of mumps vaccine should be involved into EPI.


Assuntos
Anticorpos Antivirais , Vacina contra Caxumba , Vírus da Caxumba , Caxumba , Filogenia , Vírus da Caxumba/genética , Vírus da Caxumba/imunologia , Vírus da Caxumba/classificação , Humanos , China/epidemiologia , Caxumba/epidemiologia , Caxumba/virologia , Caxumba/imunologia , Caxumba/prevenção & controle , Anticorpos Antivirais/sangue , Vacina contra Caxumba/administração & dosagem , Vacina contra Caxumba/imunologia , Adulto , Adulto Jovem , Feminino , Masculino , Genótipo , Adolescente , Criança , Imunoglobulina G/sangue , Pessoa de Meia-Idade , Pré-Escolar , Imunidade Coletiva , Variação Genética , Proteínas Virais
20.
Genomics ; 116(5): 110906, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39084477

RESUMO

Enhancers are crucial in gene expression regulation, dictating the specificity and timing of transcriptional activity, which highlights the importance of their identification for unravelling the intricacies of genetic regulation. Therefore, it is critical to identify enhancers and their strengths. Repeated sequences in the genome are repeats of the same or symmetrical fragments. There has been a great deal of evidence that repetitive sequences contain enormous amounts of genetic information. Thus, We introduce the W2V-Repeated Index, designed to identify enhancer sequence fragments and evaluates their strength through the analysis of repeated K-mer sequences in enhancer regions. Utilizing the word2vector algorithm for numerical conversion and Manta Ray Foraging Optimization for feature selection, this method effectively captures the frequency and distribution of K-mer sequences. By concentrating on repeated K-mer sequences, it minimizes computational complexity and facilitates the analysis of larger K values. Experiments indicate that our method performs better than all other advanced methods on almost all indicators.

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