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1.
Sci Adv ; 10(40): eadp8866, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39356763

RESUMO

Bioelectronic implants featuring soft mechanics, excellent biocompatibility, and outstanding electrical performance hold promising potential to revolutionize implantable technology. These biomedical implants can record electrophysiological signals and execute direct therapeutic interventions within internal organs, offering transformative potential in the diagnosis, monitoring, and treatment of various pathological conditions. However, challenges remain in improving excessive impedance at the bioelectronic-tissue interface and thus the efficacy of electrophysiological signaling and intervention. Here, we devise orbit symmetry breaking in MXene (a low-cost scalability, biocompatible, and conductive two dimensionally layered material, which we refer to as OBXene), which exhibits low bioelectronic-tissue impedance, originating from the out-of-plane charge transfer. Furthermore, the Schottky-induced piezoelectricity stemming from the asymmetric orbital configuration of OBXene facilitates interlayered charge transport in the device. We report an OBXene-based cardiac patch applied on the left ventricular epicardium of both rodent and porcine models to enable spatiotemporal epicardium mapping and pacing while coupling the wireless and battery-free operation for long-term real-time recording and closed-loop stimulation.


Assuntos
Próteses e Implantes , Animais , Suínos , Órbita/cirurgia , Impedância Elétrica , Materiais Biocompatíveis/química
2.
Int J Biol Macromol ; 280(Pt 3): 135810, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39322137

RESUMO

rAzoR2326, an azoreductase derived from Roseibium sp. H3510, functions as an FMN-dependent homodimer utilizing NADH as cofactor. It demonstrated maximum activity at 45 °C and retained moderate activity above 50 °C, exhibiting stability from pH 7-10. Evolution and structure guided rational design of wild-type rAzoR2326 (WT) efficiently yielded 6 single-point mutants with improved thermostability and activity from a 22-variant library. Further combinatorial mutation led to mutant M20 with substantially enhanced thermostability (15-fold longer half-life at 50 °C) and activity (3.24-fold higher kcat/Km). M20 exhibited superior catalytic properties for decolorizing Allura Red compared to WT. Specifically, its decolorization capacity at pH 10.0 was 4.26-fold higher than WT. Additionally, M20 demonstrated remarkable thermostability, retaining 76.83 % decolorization activity for Allura Red after 120 min at 50 °C, whereas WT nearly lost all catalytic activity under the same conditions. Molecular dynamics simulations revealed the structural changes in M20, such as improved hydrogen bonding and a new C-H···π interaction, led to a more compact and rigid enzyme structure. This resulted in a more stable FMN-binding pocket and substrate tunnel, thereby improving the catalytic stability and activity of M20. Given its enhanced dye decolorization ability and alkaline tolerance, M20 shows promise as a biocatalyst for treating azo dye effluents.

3.
PLoS One ; 19(9): e0310017, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39264966

RESUMO

OBJECTIVES: This study aimed to examine the potential correlation between myosteatosis and the prognosis of patients diagnosed with liver cirrhosis by a meta-analysis. METHODS: Cohort studies of relevance were acquired through comprehensive searches of the Medline, Web of Science, and Embase databases. To account for heterogeneity, a random-effects model was employed to combine the findings. RESULTS: The meta-analysis included 10 retrospective and four prospective cohort studies, encompassing a total of 4287 patients diagnosed with cirrhosis. The pooled findings indicated a notable decline in transplant-free survival (TFS) among individuals with liver cirrhosis and myosteatosis compared to those without this condition (risk ratio: 1.94; 95% confidence interval: 1.61 to 2.34, p < 0.001; I2 = 49%). The predefined subgroup analyses demonstrated consistent findings across various categories, including Asian and non-Asian studies, prospective and retrospective cohort studies, patients with cirrhosis overall and those who underwent transjugular intrahepatic portosystemic shunt, studies with different follow-up durations (< or ≥ 24 months), studies employing univariate and multivariate analyses, and studies with and without an adjustment for sarcopenia (p > 0.05 for all subgroup differences). Additionally, Egger's regression test indicated the presence of significant publication bias (p = 0.044). However, trim-and-fill analysis by including three hypothesized studies showed consistent results. CONCLUSIONS: The presence of myosteatosis in individuals diagnosed with liver cirrhosis may potentially be linked to a poor TFS prognosis. Further investigations are required to ascertain whether enhancing myosteatosis could potentially yield a survival advantage for this particular patient population.


Assuntos
Cirrose Hepática , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Cirrose Hepática/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática , Prognóstico , Estudos Retrospectivos , Sarcopenia/epidemiologia , Sarcopenia/etiologia
4.
Nat Genet ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251788

RESUMO

Androgen receptor (AR) is a ligand-responsive transcription factor that drives terminal differentiation of the prostatic luminal epithelia. By contrast, in tumors originating from these cells, AR chromatin occupancy is extensively reprogrammed to activate malignant phenotypes, the molecular mechanisms of which remain unknown. Here, we show that tumor-specific AR enhancers are critically reliant on H3K36 dimethyltransferase activity of NSD2. NSD2 expression is abnormally induced in prostate cancer, where its inactivation impairs AR transactivation potential by disrupting over 65% of its cistrome. NSD2-dependent AR sites distinctively harbor the chimeric FOXA1:AR half-motif, which exclusively comprise tumor-specific AR enhancer circuitries defined from patient specimens. NSD2 inactivation also engenders increased dependency on the NSD1 paralog, and a dual NSD1/2 PROTAC degrader is preferentially cytotoxic in AR-dependent prostate cancer models. Altogether, we characterize NSD2 as an essential AR neo-enhanceosome subunit that enables its oncogenic activity, and position NSD1/2 as viable co-targets in advanced prostate cancer.

5.
BMC Nurs ; 23(1): 617, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39227877

RESUMO

BACKGROUND: "The hidden costs of informal caregiving" is an interdisciplinary concept. While caregivers make a significant contribution to the process of caregiving, they sacrifice their leisure time, and incur risks of dropping out of the job, impaired mental and physical health, and decreased well-being within the context of caregiving. Those invisible sacrifices are often overlooked and described as hidden costs of informal caregiving. However, the conceptualisation of hidden costs of informal caregiving has not yet been clarified and scientifically assessed. The research aimed to clarify the concept of hidden costs of informal caregiving and develop an operational definition. METHODS: Walker and Avant's concept analysis was conducted. Databases of CBM, CNKI, WanFang, VIP, PubMed, Embase, CINAHL, Web of Science, MEDLINE, Cochrane Library, Econlit, CINAHL and ProQuest were searched with the term "hidden costs of informal caregiving". Information about the uses of the concept, defining attributes, model cases, antecedents, consequences and empirical referents of hidden costs of informal caregiving was extracted and synthesized. RESULTS: A total of 25 articles were included. The six defining attributes of hidden costs of informal caregiving were identified as including "undertaken by informal caregivers", "the time costs of caregiving", "costs of career development" "physical well-being costs", "mental well-being costs" and "social relationship costs". Personal characteristics of the caregivers and care recipients, along with caregiving attributes, were among the antecedents. The consequences of hidden costs of informal caregiving resulted in negative influences which included poor quality of life, life-altering decisions, options for the type of care, some degree of economic hardship, decreased compliance with treatment plans and monetary value informal caregivers are willing to pay to be replaced. CONCLUSION: This concept analysis decisively illuminated the hitherto nebulous concept and expanded the contents of hidden costs of informal caregiving, which will foster a deeper appreciation of the invisible cost of caregivers. Moreover, it will provide a reference for the study of the hidden costs of informal caregiving in future, contribute to the development of assessment tools and theoretical models of hidden costs of informal caregiving, and create a basis for designing an evidence-based care program.

6.
Biochem Biophys Res Commun ; 733: 150575, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39197199

RESUMO

Flavin monooxygenases (FMOs) have been widely used in the biosynthesis of natural compounds due to their excellent stereoselectivity, regioselectivity and chemoselectivity. Stenotrophomonas maltophilia flavin monooxygenase (SmFMO) has been reported to catalyze the oxidation of various thiols to corresponding sulfoxides, but its activity is relatively low. Herein, we obtained a mutant SmFMOF52G which showed 4.35-fold increase in kcat/Km (4.96 mM-1s-1) and 6.84-fold increase in enzyme activity (81.76 U/g) compared to the SmFMOWT (1.14 mM-1s-1 and 11.95 U/g) through semi-rational design guided by structural analysis and catalytic mechanism combined with high-throughput screening. By forming hydrogen bond with O4 atom of FAD isoalloxazine ring and reducing steric hindrance, the conformation of FAD isoalloxazine ring in SmFMOF52G is more stable, and NADPH and substrate are closer to FAD isoalloxazine ring, shortening the distances of hydrogen transfer and substrate oxygenation, thereby increasing the rate of reduction and oxidation reactions and enhancing enzyme activity. Additionally, the overall structural stability and substrate binding capacity of the SmFMOF52G have significant improved than that of SmFMOWT. The strategy used in this study to improve the enzyme activity of FMOs may have generality, providing important references for the rational and semi-rational engineering of FMOs.

7.
ACS Appl Mater Interfaces ; 16(35): 46538-46547, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39087831

RESUMO

The development of wearable electronic devices for human health monitoring requires materials with high mechanical performance and sensitivity. In this study, we present a novel transparent tissue-like ionogel-based wearable sensor based on silver nanowire-reinforced ionogel nanocomposites, P(AAm-co-AA) ionogel-Ag NWs composite. The composite exhibits a high stretchability of 605% strain and a moderate fracture stress of about 377 kPa. The sensor also demonstrates a sensitive response to temperature changes and electrostatic adsorption. By encapsulating the nanocomposite in a polyurethane transparent film dressing, we address issues such as skin irritation and enable multidirectional stretching. Measuring resistive changes of the ionogel nanocomposite in response to corresponding strain changes enables its utility as a highly stretchable wearable sensor with excellent performance in sensitivity, stability, and repeatability. The fabricated pressure sensor array exhibits great proficiency in stress distribution, capacitance sensing, and discernment of fluctuations in both external electric fields and stress. Our findings suggest that this material holds promise for applications in wearable and flexible strain sensors, temperature sensors, pressure sensors, and actuators.


Assuntos
Nanocompostos , Nanofios , Prata , Dispositivos Eletrônicos Vestíveis , Prata/química , Nanocompostos/química , Nanofios/química , Humanos , Géis/química , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Poliuretanos/química
8.
Int J Genomics ; 2024: 4501154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165489

RESUMO

Calcium channel blockers are emerging as a new generation of attractive anticancer drugs. SKF96365, originally thought to be a store-operated calcium entry (SOCE) inhibitor, is now often used as a TRPC channel blocker and is widely used in medical diagnostics. SKF96365 has shown antitumor effects on a variety of cancer cell lines. The objective of this study was to investigate the anticancer effect of SKF96365 on esophageal cancer in vivo and in vitro. Cell Counting Kit-8 (CCK-8) and colony formation were used to test the proliferation inhibition of SKF96365 on cell lines. Western blot and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were used to detect cell apoptosis rates. In addition, we demonstrated the antitumor effect of SKF96365 in vivo in xenografted mice. As a result, SKF96365 significantly inhibited the proliferation of K510, K30, and EC9706 in vitro. SKF96365 induces apoptosis in three cell lines through the poly(adenosine diphosphate-ribose) polymerase (PARP), caspase-9, and BCL-2 pathways in a dose-dependent and time-dependent manner. Moreover, SKF96365 treatment also induced apoptosis and inhibited tumor growth in nude mice. The calcium channel TRPC1 was significantly downregulated by SKF96365. Autophagy was also induced during the treatment of SKF96365. In summary, SKF96365 induces apoptosis (PARP, caspase-9, and BCL-2) and autophagy (LC3-A/B) by inhibiting TRPC1 in esophageal cancer cells, thereby inhibiting tumor growth.

9.
Int J Biol Macromol ; 279(Pt 2): 135139, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39208907

RESUMO

2-O-(α-d-glucopyranosyl)-sn-glycerol (2-αGG) has been applied in the food industry due to its numerous physiological benefits. The synthesis of 2-αGG can be achieved through a cascade catalytic reaction involving sucrose phosphorylase (SP) and 2-O-α-glucosylglycerol phosphorylase (GGP). However, the low substrate transfer rates between free enzymes have hindered the efficiency of 2-αGG synthesis. To address this issue, a novel technology was developed to prepare sequential multi-enzyme nanoflowers via chemical crosslinking and protein assembly, thus overcoming diffusion limitations. Specifically, spatially sequential co-immobilized enzymes, referred to as SP-GGP@Cap, were created through the targeted assembly of Bifidobacterium adolescentis SP and Marinobacter adhaerens GGP on Ca2+. This assembly was facilitated by the spontaneous protein reaction between SpyTag and SpyCatcher. Compared to free SP-GGP, SP-GGP@Cap demonstrated improved thermal and pH stability. Moreover, SP-GGP@Cap enhanced the biosynthesis of 2-αGG, achieving a relative concentration of 98 %. Additionally, it retained the ability to catalyze the substrate to yield 61 % relative concentration of 2-αGG even after ten cycles of recycling. This study presents a strategy for the spatially sequential co-immobilization of multiple enzymes in a confined environment and provides an exceptional biocatalyst for the potential industrial production of 2-αGG.

10.
Int Dent J ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39138099

RESUMO

INTRODUCTION AND AIMS: Evidence suggests an association between periodontitis and neurodegenerative diseases, but a comprehensive analysis of research trends remains absent. Therefore, we aim to identify research trends and hotspots on the comorbidity between periodontitis and neurodegenerative diseases, understand mechanisms, provide guidance for subsequent studies and show its clinical translational possibility. METHODS: A bibliometric analysis covering 1982 to 2023 was conducted using the Web of Science Core Collection. English-language articles range from January 1, 1982 to November 30, 2023 were analyzed. Data were downloaded on November 30, 2023 and analyzed on December, 2023. Data visualization and statistical analysis were performed to identify trends of annual publications, countries, sources, institutions, authors, most cited articles, and keywords by using Microsoft Excel, VOSviewer, Citespace, R-bibliometrix and Origin Pro. RESULTS: A total of 1,238 articles from 1982 to 2023 on the comorbidity between periodontitis and neurodegenerative diseases were identified. Annual publications showed an upward trend. The United States, University College of London, BRAIN and Shy, Michael E. were the leading nation, affiliation, source and author, respectively. The United States, NEUROLOGY, and Curtis Maurice A. were the most cited nation, source, and author. Keywords network analysis highlighted 'Charcot-Marie-Tooth Disease', 'Alzheimer's Disease' and 'Periodontitis' as focal points. Detection of keywords citation bursts demonstrated 'Porphyromonas gingivalis' and 'Cognitive Dysfunction' as hot topics in recent research. CONCLUSIONS: In recent years, emerging interests of the comorbidity between periodontitis and neurodegenerative diseases (NDs) are growing. Our study enhances the understanding of recent research trends of periodontitis and NDs and provides valuable perspectives within this expanding field, offering new insights into research trends regarding the interplay between 'Porphyromonas gingivalis' and 'Cognitive Dysfunction'. Further research of the molecular mechanisms between P. gingivalis-induced periodontitis, neuroinflammation, that leads neurodegeneration are clearly warranted.

11.
Front Plant Sci ; 15: 1336580, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974984

RESUMO

Plant protection unmanned aerial vehicles (UAVs) have become popular in mountain orchards, but due to the differences in planting structures, the chances of heavy spraying, missed spraying and pesticide drift are increasing. To mitigate the adverse effects of these phenomena, it is necessary to clarify the effective deposition range of aerial spray droplets. This study proposed an effective spray swath determination method for the effective spraying range of mountainous orchards with UAVs equipped with a mist nozzle (bilateral 1% coverage). This approach focused on exploring the effects of flight height (unidirectional flight modes of 2, 3 and 4 m), spray nozzle atomization performance (reciprocating flight modes of 20, 30 and 40 µm) and flight route (treetop flying and inter-row flying) on the spraying range in a mountain setting. In addition, the study analysed the relationship between the droplet-size spectrum and the effective swath position. The results showed that it is feasible to use the bilateral 1% coverage evaluation method to determine the effective spray swath of a UAV adapted with a mist nozzle for aerial operation in a mountainous Nangguo Pear orchard. With the increase in UAV flight height (2-4 m), the effective unidirectional spray swath also increased, and with the increase in atomization level (20-40 µm), the effective reciprocating spray swath showed a decreasing trend. Moreover, the average effective swath width measured by the UAV for treetop flight was greater than that measured for inter-row flight. The study also found that the proportion of small droplets (droplet size less than 100 µm) below the UAV route was lower (approximately 50%) than along the sides of the route (approximately 80%), and the spray swath was not symmetrically distributed along the flight route but shifted laterally by approximately 3 to 4 m in the downhill direction.

12.
Bioengineering (Basel) ; 11(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39061743

RESUMO

Neutral pullulanases, having a good application prospect in trehalose production, showed a limited expression level. In order to address this issue, two approaches were utilized to enhance the yield of a new neutral pullulanase variant (PulA3E) in B. subtilis. One involved using multiple copies of genome integration to increase its expression level and fermentation stability. The other focused on enhancing the PulA-type atypical secretion pathway to further improve the secretory expression of PulA3E. Several strains with different numbers of genome integrations, ranging from one to four copies, were constructed. The four-copy genome integration strain PD showed the highest extracellular pullulanase activity. Additionally, the integration sites ytxE, ytrF, and trpP were selected based on their ability to enhance the PulA-type atypical secretion pathway. Furthermore, overexpressing the predicated regulatory genes comEA and yvbW of the PulA-type atypical secretion pathway in PD further improved its extracellular expression. Three-liter fermenter scale-up production of PD and PD-ARY yielded extracellular pullulanase activity of 1767.1 U/mL at 54 h and 2465.1 U/mL at 78 h, respectively. Finally, supplementing PulA3E with 40 U/g maltodextrin in the multi-enzyme catalyzed system resulted in the highest trehalose production of 166 g/L and the substrate conversion rate of 83%, indicating its potential for industrial application.

13.
J Nanobiotechnology ; 22(1): 437, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39061092

RESUMO

BACKGROUND: The oral administration of drugs for treating ulcerative colitis (UC) is hindered by several factors, including inadequate gastrointestinal stability, insufficient accumulation in colonic lesions, and uncontrolled drug release. METHODS: A multiple sensitive nano-delivery system comprising ß-cyclodextrin (CD) and 4-(hydroxymethyl)phenylboronic acid (PAPE) with enzyme/reactive oxygen species (ROS) sensitivity was developed to load celastrol (Cel) as a comprehensive treatment for UC. RESULTS: Owing to the positive charge in the site of inflamed colonic mucosa, the negatively charged nanomedicine (Cel/NPs) could efficiently accumulate. Expectedly, Cel/NPs showed excellent localization ability to colon in vitro and in vivo tests. The elevated concentration of ROS and intestinal enzymes in the colon microenvironment quickly break the CD, resulting in Cel release partially to rebalance microbiota and recover the intestinal barrier. The accompanying cellular internalization of residual Cel/NPs, along with the high concentration of cellular ROS to trigger Cel burst release, could decrease the expression of inflammatory cytokines, inhibit colonic cell apoptosis, promote the macrophage polarization, scavenge ROS, and regulate the TLR4/NF-κB signaling pathway, which certified that Cel/NPs possessed a notably anti-UC therapy outcome. CONCLUSIONS: We provide a promising strategy for addressing UC symptoms via an enzyme/ROS-sensitive oral platform capable of releasing drugs on demand.


Assuntos
Colite Ulcerativa , Triterpenos Pentacíclicos , Espécies Reativas de Oxigênio , Colite Ulcerativa/tratamento farmacológico , Triterpenos Pentacíclicos/farmacologia , Triterpenos Pentacíclicos/uso terapêutico , Animais , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Humanos , Nanopartículas/química , beta-Ciclodextrinas/química , Masculino , Células RAW 264.7 , Inflamação/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Colo/metabolismo , Colo/efeitos dos fármacos , Liberação Controlada de Fármacos , Camundongos Endogâmicos C57BL , Triterpenos/farmacologia , Triterpenos/química , Sistemas de Liberação de Fármacos por Nanopartículas/química , Mucosa Intestinal/metabolismo
14.
J Cancer ; 15(14): 4686-4699, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006068

RESUMO

Background: SLC30A5, a member of the solute transporter protein family, is implicated in tumorigenesis and cancer progression. This study aimed to explore the expression and prognostic significance of SLC30A family genes in pan-cancer, with a specific emphasis on SLC30A5 in hepatocellular carcinoma (HCC). Methods: Expression patterns and prognostic implications of SLC30A family genes were assessed across 33 cancer types, especially HCC. Co-expression analysis explored the relationship between SLC30A5 and immune cell infiltration, immune checkpoints, pathway molecules related to tumor angiogenesis and epithelial-mesenchymal transition (EMT). The role of SLC30A5 in HCC was evaluated through in vitro and in vivo assays, including CCK8 viability assay, EdU cell proliferation assay, colony formation assay, apoptosis assay, wound healing assay, transwell migration assay, and xenograft mouse model assay using Huh7 cells with targeted knockdown of SLC30A5. Results: SLC30A family genes exhibited overexpression in various tumors. In HCC, upregulation of SLC30A5 expression correlated with adverse prognosis. Significant associations were observed between SLC30A5 expression and immune cell infiltration, immune checkpoints, molecules involved in angiogenesis, and EMT. SLC30A5 overexpression was associated with advanced disease stages, higher histological grades, and vascular invasion. Single-cell RNA sequencing data (GSE112271) revealed notable SLC30A5 expression in malignant cells. In vitro and in vivo assays demonstrated that SLC30A5 knockdown in Huh7 cells reduced proliferation, migration, and invasion while promoting apoptosis. Conclusions: This study highlights the clinical relevance of SLC30A5 in HCC, emphasizing its role in cell proliferation and migration. SLC30A5 emerges as a promising candidate for a prognostic marker and a potential target in HCC.

15.
mLife ; 3(1): 57-73, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38827513

RESUMO

O-glycosylation is an ancient yet underappreciated protein posttranslational modification, on which many bacteria and viruses heavily rely to perform critical biological functions involved in numerous infectious diseases or even cancer. But due to the innate complexity of O-glycosylation, research techniques have been limited to study its exact role in viral attachment and entry, assembly and exit, spreading in the host cells, and the innate and adaptive immunity of the host. Recently, the advent of many newly developed methodologies (e.g., mass spectrometry, chemical biology tools, and molecular dynamics simulations) has renewed and rekindled the interest in viral-related O-glycosylation in both viral proteins and host cells, which is further fueled by the COVID-19 pandemic. In this review, we summarize recent advances in viral-related O-glycosylation, with a particular emphasis on the mucin-type O-linked α-N-acetylgalactosamine (O-GalNAc) on viral proteins and the intracellular O-linked ß-N-acetylglucosamine (O-GlcNAc) modifications on host proteins. We hope to provide valuable insights into the development of antiviral reagents or vaccines for better prevention or treatment of infectious diseases.

16.
J Agric Food Chem ; 72(25): 14302-14314, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38865607

RESUMO

In this work, lactoferrin (LF)-chitosan (CS) composite hydrogels with good loading capacity of thermosensitive bioactive substances were successfully obtained by microbial transglutaminase (MTG)-induced cross-linking. We evaluated the rheological, textural, and microstructural characteristics of the composite hydrogels under different conditions. The results demonstrated that the concentrations of LF and CS as well as the amount of MTG could regulate the textural properties, rheological properties, and water holding capability. The results of FTIR and fluorescence spectroscopy indicated that the main interactions within the composite gel were hydrogen and isopeptide bonds. Additionally, in vitro digestion simulation results verified that riboflavin kept stable in stomach due to the protection of LF-CS composite hydrogels and was released in small intestine. These results suggested that thermosensitive bioactive substance could be encapsulated and delivered by the LF-CS composite hydrogel, which could be applied in lots of potential applications in functional food as a new material.


Assuntos
Quitosana , Hidrogéis , Lactoferrina , Reologia , Transglutaminases , Transglutaminases/química , Transglutaminases/metabolismo , Hidrogéis/química , Quitosana/química , Lactoferrina/química , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Digestão
17.
Artigo em Inglês | MEDLINE | ID: mdl-38875084

RESUMO

The rapid development of large language models (LLMs), such as ChatGPT, has revolutionized the efficiency of creating programming tutorials. LLMs can be instructed with text prompts to generate comprehensive text descriptions for code snippets provided by users. However, the lack of transparency in the end-to-end generation process has hindered the understanding of model behavior and limited user control over the generated results. To tackle this challenge, we introduce a novel approach that breaks down the programming tutorial creation task into actionable steps. By employing the tree-of-thought method, LLMs engage in an exploratory process to generate diverse and faithful programming tutorials. We then present SPROUT, an authoring tool equipped with a series of interactive visualizations that empower users to have greater control and understanding of the programming tutorial creation process. A formal user study demonstrated the effectiveness of SPROUT, showing that our tool assists users to actively participate in the programming tutorial creation process, leading to more reliable and customizable results. By providing users with greater control and understanding, SPROUT enhances the user experience and improves the overall quality of programming tutorial.A free copy of this paper and all supplemental materials are available at https://osf.io/uez2t/?view only = 5102e958802341daa414707646428f86.

18.
Nat Commun ; 15(1): 4777, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839748

RESUMO

Drawing inspiration from cohesive integration of skeletal muscles and sensory skins in vertebrate animals, we present a design strategy of soft robots, primarily consisting of an electronic skin (e-skin) and an artificial muscle. These robots integrate multifunctional sensing and on-demand actuation into a biocompatible platform using an in-situ solution-based method. They feature biomimetic designs that enable adaptive motions and stress-free contact with tissues, supported by a battery-free wireless module for untethered operation. Demonstrations range from a robotic cuff for detecting blood pressure, to a robotic gripper for tracking bladder volume, an ingestible robot for pH sensing and on-site drug delivery, and a robotic patch for quantifying cardiac function and delivering electrotherapy, highlighting the application versatilities and potentials of the bio-inspired soft robots. Our designs establish a universal strategy with a broad range of sensing and responsive materials, to form integrated soft robots for medical technology and beyond.


Assuntos
Robótica , Robótica/instrumentação , Robótica/métodos , Animais , Biomimética/métodos , Biomimética/instrumentação , Humanos , Próteses e Implantes , Pele , Desenho de Equipamento , Músculo Esquelético/fisiologia , Dispositivos Eletrônicos Vestíveis
19.
Int J Biol Macromol ; 273(Pt 2): 133057, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38866295

RESUMO

Poly (butylene adipate-co-terephthalate)/poly (L-lactic acid) (PBAT/PLLA) is one of the most important biodegradable polymer combinations; however, they are flammable with heavy melt dripping and incompatible. To achieve the objective of flame retardation and compatibility, a hybrid polyurethane (PU) with multiple flame retardation elements is synthesized via a new ring-opening polymerization (ROP) method and integrated into PBAT/PLLA film. The PU not only dissolves in different organic solvents at mild temperature but also improves the compatibility of PBAT/PLLA. As PU with respect to PBAT/PLLA is 20 wt%, the limiting oxygen index (LOI) and UL-94 reach 25.5 % and V-0 rating, respectively. In cone calorimeter test, the peak heat release rate (pHRR) of PU/PBAT/PLLA is ahead of PBAT/PLLA, and the total heat release (THR) decreases to 25.85 MJ/m2. The fire safety is achieved successfully. The initial pyrolysis of PU promotes the formation of a seed carbon layer; it continuously breaks down into a series of phosphorus­oxygen radicals and generates different inert gases, while the pyrolytic solid products accelerate the carbonization to form the carbon/silicon composite layer. Then the polymeric combustion is braked completely. Besides, the PU can also tune the mechanical properties of PBAT/PLLA film and enhance its hydrophobicity. This work opens a new window for developing multifunctional flame retardant and paves the way for the richening engineering application of PBAT/PLLA.


Assuntos
Retardadores de Chama , Poliésteres , Poliuretanos , Poliuretanos/química , Poliésteres/química , Ácidos Ftálicos/química , Polimerização
20.
J Hazard Mater ; 474: 134779, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850935

RESUMO

Bisphenol A (BPA), an endocrine disrupter with estrogen activity, can infiltrate animal and human bodies through the food chain. Enzymatic degradation of BPA holds promise as an environmentally friendly approach while it is limited due to lower stability and recycling challenges. In this study, laccase from Bacillus pumilus TCCC 11568 was expressed in Pichia pastoris (fLAC). The optimal catalytic conditions for fLAC were at pH 6.0 and 80 °C, with a half-life T1/2 of 120 min at 70 °C. fLAC achieved a 46 % degradation rate of BPA, and possible degradation pathways were proposed based on identified products and reported intermediates of BPA degradation. To improve its stability and degradation capacity, a whole-cell biocatalyst (WCB) was developed by displaying LAC (dLAC) on the surface of P. pastoris GS115. The functionally displayed LAC demonstrated enhanced thermostability and pH stability along with an improved BPA degradation ability, achieving a 91 % degradation rate. Additionally, dLAC maintained a degradation rate of over 50 % after the fourth successive cycles. This work provides a powerful catalyst for degrading BPA, which might decontaminate endocrine disruptor-contaminated water through nine possible pathways.


Assuntos
Bacillus pumilus , Compostos Benzidrílicos , Biodegradação Ambiental , Disruptores Endócrinos , Lacase , Fenóis , Compostos Benzidrílicos/metabolismo , Lacase/metabolismo , Lacase/genética , Fenóis/metabolismo , Bacillus pumilus/enzimologia , Bacillus pumilus/genética , Bacillus pumilus/metabolismo , Disruptores Endócrinos/metabolismo , Concentração de Íons de Hidrogênio , Saccharomycetales/metabolismo , Saccharomycetales/genética
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