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1.
Artigo em Inglês | MEDLINE | ID: mdl-38629946

RESUMO

A novel Gram-stain-negative, yellow-pigmented, short rod-shaped bacterial strain, HBC34T, was isolated from a freshwater sample collected from Daechung Reservoir, Republic of Korea. The results of 16S rRNA gene sequence analysis indicated that HBC34T was affiliated with the genus Sphingobium and shared the highest sequence similarity to the type strains of Sphingobium vermicomposti (98.01 %), Sphingobium psychrophilum (97.87 %) and Sphingobium rhizovicinum (97.59 %). The average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values between HBC34T and species of the genus Sphingobium with validly published names were below 84.01 and 28.1 %, respectively. These values were lower than the accepted species-delineation thresholds, supporting its recognition as representing a novel species of the genus Sphingobium. The major fatty acids (>10 % of the total fatty acids) were identified as summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The main polar lipids were phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, two phospholipids and two unidentified polar lipids. The respiratory quinone was Q-10. The genomic DNA G+C content of HBC34T was 64.04 %. The polyphasic evidence supports the classification of HBC34T as the type strain of a novel species of the genus Sphingobium, for which the name Sphingobium cyanobacteriorum sp. nov is proposed. The type strain is HBC34T (= KCTC 8002T= LMG 33140T).


Assuntos
Ácidos Graxos , Água Doce , Composição de Bases , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Filogenia , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
2.
Appl Microbiol Biotechnol ; 108(1): 466, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283515

RESUMO

Cyanobacterial harmful algal blooms, particularly those dominated by Microcystis, pose significant ecological and health risks worldwide. This review provides an overview of the latest advances in biotechnological approaches for mitigating Microcystis blooms, focusing on cyanobactericidal bacteria, fungi, eukaryotic microalgae, zooplankton, aquatic plants, and cyanophages. Recently, promising results have been obtained using cyanobactericidal bacteria: not through the inoculation of cultured bacteria, but rather by nurturing those already present in the periphyton or biofilms of aquatic plants. Fungi and eukaryotic microalgae also exhibit algicidal properties; however, their practical applications still face challenges. Zooplankton grazing on Microcystis can improve water quality, but hurdles exist because of the colonial form and toxin production of Microcystis. Aquatic plants control blooms through allelopathy and nutrient absorption. Although cyanophages hold promise for Microcystis control, their strain-specificity hinders widespread use. Despite successful laboratory validation, field applications of biological methods are limited. Future research should leverage advanced molecular and bioinformatic techniques to understand microbial interactions during blooms and offer insights into innovative control strategies. Despite progress, the efficacy of biological methods under field conditions requires further verification, emphasizing the importance of integrating advanced multi-meta-omics techniques with practical applications to address the challenges posed by Microcystis blooms. KEY POINTS: • A diverse range of biotechnological methods is presented for suppressing Microcystis blooms. • Efficacy in laboratory experiments needs to be proved further in field applications. • Multi-meta-omics techniques offer novel insights into Microcystis dynamics and interactions.


Assuntos
Biotecnologia , Proliferação Nociva de Algas , Microalgas , Microcystis , Microcystis/crescimento & desenvolvimento , Biotecnologia/métodos , Microalgas/crescimento & desenvolvimento , Fungos/fisiologia , Zooplâncton/fisiologia , Animais , Bactérias/metabolismo , Bactérias/crescimento & desenvolvimento , Bacteriófagos/fisiologia
3.
Int J Hosp Manag ; 109: 103400, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36439897

RESUMO

In this study, using the Protection Motivation Theory (PMT), we examine whether protection motivation can explain restaurant patron intention to practice self-protection. New normal practices are in place in the restaurant industry that influence dining out behavior during the COVID-19 pandemic. Based on 402 usable questionnaires collected face to face with residents in Phuket, Thailand, and using structural equation modeling to analyze the data, we found self-protective intention is influenced more by the perceived threat of COVID-19, but the actual behavior of visit frequency and protective behavior is influenced more by the positive PMT factors: perceived efficacy or self-confidence about protecting oneself and the expected rewards of dining out. In addition, the study highlights the important role of self-protective intention as a mediator in the relationships between PMT factors and actual behaviors of restaurant clients, especially their protection behaviors. Academic and practical implications are discussed.

4.
J Am Chem Soc ; 144(14): 6261-6269, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35297615

RESUMO

The remarkable underwater adhesion of mussel foot proteins has long been an inspiration in the design of peptidomimetic materials. Although the synergistic wet adhesion of catechol and lysine has been recently highlighted, the critical role of the polymeric backbone has remained largely underexplored. Here, we present a peptidomimetic approach using poly(ethylene glycol) (PEG) as a platform to evaluate the synergistic compositional relation between the key amino acid residues (i.e., DOPA and lysine), as well as the role of the polyether backbone in interfacial adhesive interactions. A series of PEG-based peptides (PEGtides) were synthesized using functional epoxide monomers corresponding to catechol and lysine via anionic ring-opening polymerization. Using a surface force apparatus, highly synergistic surface interactions among these PEGtides with respect to the relative compositional ratio were revealed. Furthermore, the critical role of the catechol-amine synergy and diverse hydrogen bonding within the PEGtides in the superior adhesive interactions was verified by molecular dynamics simulations. Our study sheds light on the design of peptidomimetic polymers with reduced complexity within the framework of a polyether backbone.


Assuntos
Bivalves , Peptidomiméticos , Adesivos/química , Animais , Ligação de Hidrogênio , Lisina/química , Polímeros/química , Proteínas/química
5.
Sensors (Basel) ; 22(12)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35746394

RESUMO

The development of recent image style transfer methods allows the quick transformation of an input content image into an arbitrary style. However, these methods have a limitation that the scale-across style pattern of a style image cannot be fully transferred into a content image. In this paper, we propose a new style transfer method, named total style transfer, that resolves this limitation by utilizing intra/inter-scale statistics of multi-scaled feature maps without losing the merits of the existing methods. First, we use a more general feature transform layer that employs intra/inter-scale statistics of multi-scaled feature maps and transforms the multi-scaled style of a content image into that of a style image. Secondly, we generate a multi-scaled stylized image by using only a single decoder network with skip-connections, in which multi-scaled features are merged. Finally, we optimize the style loss for the decoder network in the intra/inter-scale statistics of image style. Our improved total style transfer can generate a stylized image with a scale-across style pattern from a pair of content and style images in one forwarding pass. Our method achieved less memory consumption and faster feed-forwarding speed compared with the recent cascade scheme and the lowest style loss among the recent style transfer methods.


Assuntos
Projetos de Pesquisa
6.
Sensors (Basel) ; 22(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36366125

RESUMO

Recent image-style transfer methods use the structure of a VGG feature network to encode and decode the feature map of the image. Since the network is designed for the general image-classification task, it has a number of channels and, accordingly, requires a huge amount of memory and high computational power, which is not mandatory for such a relatively simple task as image-style transfer. In this paper, we propose a new technique to size down the previously used style transfer network for eliminating the redundancy of the VGG feature network in memory consumption and computational cost. Our method automatically finds a number of consistently inactive convolution channels during the network training phase by using two new losses, i.e., channel loss and xor loss. The former maximizes the number of inactive channels and the latter fixes the positions of these inactive channels to be the same for the image. Our method improves the image generation speed to be up to 49% faster and reduces the number of parameters by 20% while maintaining style transferring performance. Additionally, our losses are also effective in pruning the VGG16 classifier network, i.e., parameter reduction by 26% and top-1 accuracy improvement by 0.16% on CIFAR-10.


Assuntos
Aumento da Imagem , Redes Neurais de Computação , Aumento da Imagem/métodos
7.
Int J Mol Sci ; 23(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35886987

RESUMO

(1) Objective: In order to evaluate the effect of a pre-induced mesenchymal stem cell (MSC)-coated cellulose/collagen nanofibrous nerve conduit on facial nerve regeneration in a rat model both in vitro and in vivo. (2) Methods: After fabrication of the cellulose/collagen nanofibrous conduit, its lumen was coated with either MSCs or pre-induced MSCs. The nerve conduit was then applied to the defective main trunk of the facial nerve. Rats were randomly divided into three treatment groups (n = 10 in each): cellulose/collagen nanofiber (control group), cellulose/collagen nanofiber/MSCs (group I), and cellulose/collagen nanofiber/pre-induced MSCs (group II). (3) Results Fibrillation of the vibrissae of each group was observed, and action potential threshold was compared 8 weeks post-surgery. Histopathological changes were also observed. Groups I and II showed better recovery of vibrissa fibrillation than the control group. (4) Conclusions: Group II, treated with the pre-induced MSC-coated cellulose/collagen nanofibrous nerve conduit, showed the highest degree of recovery based on functional and histological evaluations.


Assuntos
Celulose , Colágeno , Nervo Facial , Células-Tronco Mesenquimais , Nanofibras , Regeneração Nervosa , Animais , Celulose/farmacologia , Materiais Revestidos Biocompatíveis , Colágeno/farmacologia , Modelos Animais de Doenças , Nervo Facial/efeitos dos fármacos , Nervo Facial/fisiologia , Regeneração Tecidual Guiada , Células-Tronco Mesenquimais/fisiologia , Nanofibras/administração & dosagem , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/fisiologia , Ratos , Nervo Isquiático/patologia , Alicerces Teciduais
8.
Biomacromolecules ; 22(12): 5173-5184, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34818000

RESUMO

Despite the widespread use of polymers for antifouling coatings, the effect of the polymeric topology on the antifouling property has been largely underexplored. Unlike conventional brush polymers, a loop conformation often leads to strong steric stabilization of surfaces and antifouling and lubricating behavior owing to the large excluded volume and reduced chain ends. Herein, we present highly antifouling multiloop polyethers functionalized with a mussel-inspired catechol moiety with varying loop dimensions. Specifically, a series of polyethers with varying catechol contents were synthesized via anionic ring-opening polymerization by using triethylene glycol glycidyl ether (TEG) and catechol-acetonide glycidyl ether (CAG) to afford poly(TEG-co-CAG)n. The versatile adsorption and antifouling effects of multiloop polyethers were evaluated using atomic force microscopy and a quartz crystal microbalance with dissipation. Furthermore, the crucial role of the loop dimension in the antifouling properties was analyzed via a surface force apparatus and a cell attachment assay. This study provides a new platform for the development of versatile antifouling polymers with varying topologies.


Assuntos
Incrustação Biológica , Adsorção , Incrustação Biológica/prevenção & controle , Microscopia de Força Atômica , Polímeros/química , Propriedades de Superfície
9.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070420

RESUMO

Oct4 is an important mammalian POU family transcription factor expressed by early human embryonic stem cells (hESCs). The precise level of Oct4 governs the pluripotency and fate determination of hESCs. Several post-translational modifications (PTMs) of Oct4 including phosphorylation, ubiquitination, and SUMOylation have been reported to regulate its critical functions in hESCs. Ubiquitination and deubiquitination of Oct4 should be well balanced to maintain the pluripotency of hESCs. The protein turnover of Oct4 is regulated by several E3 ligases through ubiquitin-mediated degradation. However, reversal of ubiquitination by deubiquitinating enzymes (DUBs) has not been reported for Oct4. In this study, we generated a ubiquitin-specific protease 3 (USP3) gene knockout using the CRISPR/Cas9 system and demonstrated that USP3 acts as a protein stabilizer of Oct4 by deubiquitinating Oct4. USP3 interacts with endogenous Oct4 and co-localizes in the nucleus of hESCs. The depletion of USP3 leads to a decrease in Oct4 protein level and loss of pluripotent morphology in hESCs. Thus, our results show that USP3 plays an important role in controlling optimum protein level of Oct4 to retain pluripotency of hESCs.


Assuntos
Carcinoma Embrionário/genética , Enzimas Desubiquitinantes/metabolismo , Células-Tronco Embrionárias/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Sistemas CRISPR-Cas , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Enzimas Desubiquitinantes/genética , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/enzimologia , Técnicas de Inativação de Genes , Humanos , Fator 3 de Transcrição de Octâmero/genética , Ligação Proteica , Processamento de Proteína Pós-Traducional , Estabilidade Proteica , Análise de Célula Única , Proteases Específicas de Ubiquitina/genética , Ubiquitinação/genética
10.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209900

RESUMO

Adult human cardiomyocytes have an extremely limited proliferative capacity, which poses a great barrier to regenerative medicine and research. Human embryonic stem cells (hESCs) have been proposed as an alternative source to generate large numbers of clinical grade cardiomyocytes (CMs) that can have potential therapeutic applications to treat cardiac diseases. Previous studies have shown that bioactive lipids are involved in diverse cellular responses including cardiogenesis. In this study, we explored the novel function of the chemically synthesized bioactive lipid O-cyclic phytosphingosine-1-phosphate (cP1P) as an inducer of cardiac differentiation. Here, we identified cP1P as a novel factor that significantly enhances the differentiation potential of hESCs into cardiomyocytes. Treatment with cP1P augments the beating colony number and contracting area of CMs. Furthermore, we elucidated the molecular mechanism of cP1P regulating SMAD1/5/8 signaling via the ALK3/BMP receptor cascade during cardiac differentiation. Our result provides a new insight for cP1P usage to improve the quality of CM differentiation for regenerative therapies.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Esfingosina/análogos & derivados , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/fisiologia , Humanos , Lipídeos/química , Lipídeos/farmacologia , Miócitos Cardíacos/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Esfingosina/química , Esfingosina/farmacologia
11.
Sensors (Basel) ; 20(5)2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182772

RESUMO

Photoplethysmography (PPG) is an easy and convenient method by which to measure heart rate (HR). However, PPG signals that optically measure volumetric changes in blood are not robust to motion artifacts. In this paper, we develop a PPG measuring system based on multi-channel sensors with multiple wavelengths and propose a motion artifact reduction algorithm using independent component analysis (ICA). We also propose a truncated singular value decomposition for 12-channel PPG signals, which contain direction and depth information measured using the developed multi-channel PPG measurement system. The performance of the proposed method is evaluated against the R-peaks of an electrocardiogram in terms of sensitivity (Se), positive predictive value (PPV), and failed detection rate (FDR). The experimental results show that Se, PPV, and FDR were 99%, 99.55%, and 0.45% for walking, 96.28%, 99.24%, and 0.77% for fast walking, and 82.49%, 99.83%, and 0.17% for running, respectively. The evaluation shows that the proposed method is effective in reducing errors in HR estimation from PPG signals with motion artifacts in intensive motion situations such as fast walking and running.


Assuntos
Artefatos , Fotopletismografia/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Dispositivos Eletrônicos Vestíveis , Adulto , Eletrocardiografia , Desenho de Equipamento , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Caminhada/fisiologia , Adulto Jovem
12.
EMBO Rep ; 18(1): 61-71, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27979972

RESUMO

Hippo signaling controls organ size by regulating cell proliferation and apoptosis. Yes-associated protein (YAP) is a key downstream effector of Hippo signaling, and LATS-mediated phosphorylation of YAP at Ser127 inhibits its nuclear localization and transcriptional activity. Here, we report that Nemo-like kinase (NLK) phosphorylates YAP at Ser128 both in vitro and in vivo, which blocks interaction with 14-3-3 and enhances its nuclear localization. Depletion of NLK increases YAP phosphorylation at Ser127 and reduces YAP-mediated reporter activity. These results suggest that YAP phosphorylation at Ser128 and at Ser127 may be mutually exclusive. We also find that with the increase in cell density, nuclear localization and the level of NLK are reduced, resulting in reduction in YAP phosphorylation at Ser128. Furthermore, knockdown of Nemo (the Drosophila NLK) in fruit fly wing imaginal discs results in reduced expression of the Yorkie (the Drosophila YAP) target genes expanded and DIAP1, while Nemo overexpression reciprocally increased the expression. Overall, our data suggest that NLK/Nemo acts as an endogenous regulator of Hippo signaling by controlling nuclear localization and activity of YAP/Yorkie.


Assuntos
Proteínas 14-3-3/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Contagem de Células , Proteínas de Ciclo Celular , Linhagem Celular , Movimento Celular , Núcleo Celular/metabolismo , Drosophila , Humanos , Camundongos , Proteínas Nucleares/química , Fosforilação , Ligação Proteica , Transporte Proteico , Serina/química , Serina/metabolismo , Fatores de Transcrição/química , Transcrição Gênica
13.
Biochem J ; 450(1): 9-21, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23343194

RESUMO

Wnt/ß-catenin signalling plays essential roles in embryonic development as well as tissue homoeostasis in adults. Thus abnormal regulation of Wnt/ß-catenin signalling is linked to a variety of human diseases, including cancer, osteoporosis and Alzheimer's disease. Owing to the importance of Wnt signalling in a wide range of biological fields, a better understanding of its precise mechanisms could provide fundamental insights for therapeutic applications. Although many studies have investigated the regulation of Wnt/ß-catenin signalling, our knowledge remains insufficient due to the complexity and diversity of Wnt signalling. It is generally accepted that the identification of novel regulators and their functions is a prerequisite to fully elucidating the regulation of Wnt/ß-catenin signalling. Recently, several novel modulators of Wnt signalling have been determined through multiple genetic and proteomic approaches. In the present review, we discuss the mechanistic regulation of Wnt/ß-catenin signalling by focusing on the roles of these novel regulators.


Assuntos
Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas Desgrenhadas , Humanos , Modelos Biológicos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Transcrição Gênica , Proteínas Wnt/genética , beta Catenina/genética
14.
Behav Sci (Basel) ; 14(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39062382

RESUMO

This study explores the psychological motivations that drive ChatGPT users to embrace and sustain the use of such technology based on the fundamental notion of the environmental psychology theory, including servicescapes. To do so, this study delves into the influence of ChatGPT's e-servicescapes on users' emotional states and intention to engage with ChatGPT for decision-making processes. This study conducted an online survey among ChatGPT users in the United States. Structural equation modeling revealed that negative emotions were significantly influenced by various e-servicescape sub-dimensions, including security, visual appeal, entertainment value, originality of design, and social factors. Positive emotions, on the other hand, were influenced by factors such as visual appeal, customization, interactivity, and relevance of information. Both positive and negative emotions significantly affected user satisfaction, which, in turn, shaped their behavioral intention to engage with ChatGPT. This study contributes to the understanding of digital environmental psychology and chatbots by extending the notion of e-servicescapes to the context of AI-based services. It underscores the significance of e-servicescapes in shaping user experiences and provides valuable insights for business scholars and marketing practitioners.

15.
Tissue Eng Regen Med ; 21(1): 97-109, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38079100

RESUMO

BACKGROUND: Collagen is a key component of connective tissue and has been frequently used in the fabrication of medical devices for tissue regeneration. Human-originated collagen is particularly appealing due to its low immune response as an allograft biomaterial compared to xenografts and its ability to accelerate the regeneration process. Ethically and economically, adipose tissues available from liposuction clinics are a good resource to obtain human collagen. However, studies are still scarce on the extraction and characterization of human collagen, which originates from adipose tissue. The aim of this study is to establish a novel and simple method to extract collagen from human adipose tissue, characterize the collagen, and compare it with commercial-grade porcine collagen for tissue engineering applications. METHODS: We developed a method to extract the collagen from human adipose tissue under quasi-Good Manufacturing Practice (GMP) conditions, including freezing the tissue, blood removal, and ethanol-based purification. Various techniques, including protein quantification, decellularization assessment, SDS-PAGE, FTIR, and CD spectroscopy analysis, were used for characterization. Amino acid composition was compared with commercial collagen. Biocompatibility and cell proliferation tests were performed, and in vitro tests using collagen sponge scaffolds were conducted with statistical analysis. RESULTS: Our results showed that this human adipose-derived collagen was equivalent in quality to commercially available porcine collagen. In vitro testing demonstrated high cell attachment and the promotion of cell proliferation. CONCLUSION: In conclusion, we developed a simple and novel method to extract and characterize collagen and extracellular matrix from human adipose tissue, offering a potential alternative to animal-derived collagen for xeno-free tissue engineering applications.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Suínos , Animais , Humanos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Tecido Adiposo/metabolismo , Colágeno/química , Matriz Extracelular
16.
Adv Sci (Weinh) ; : e2406905, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007503

RESUMO

Due to its outstanding physical and chemical properties, graphene synthesized by laser scribing on polyimide (PI) offers excellent opportunities for photothermal applications, antiviral and antibacterial surfaces, and electrochemical storage and sensing. However, the utilization of such graphene for imaging is yet to be explored. Herein, using chemically durable and electrically conductive laser-induced graphene (LIG) for tomography imaging in aqueous suspensions is proposed. These graphene electrodes are designed as impedance imaging units for four-terminal electrical measurements. Using the real-time portable imaging prototypes, the conductive and dielectric objects can be seen in clear and muddy water with equivalent impedance modeling. This low-cost graphene tomography measurement system offers significant advantages over traditional visual cameras, in which the suspended muddy particles hinder the imaging resolution. This research shows the potential of applying graphene nanomaterials in emerging marine technologies, such as underwater robotics and automatic fisheries.

17.
Stem Cells Transl Med ; 13(7): 637-647, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838263

RESUMO

Extracellular vesicles, particularly exosomes, have emerged as promising drug delivery systems owing to their unique advantages, such as biocompatibility, immune tolerability, and target specificity. Various engineering strategies have been implemented to harness these innate qualities, with a focus on enhancing the pharmacokinetic and pharmacodynamic properties of exosomes via payload loading and surface engineering for active targeting. This concise review outlines the challenges in the development of exosomes as drug carriers and offers insights into strategies for their effective clinical translation. We also highlight preclinical studies that have successfully employed anti-inflammatory exosomes and suggest future directions for exosome therapeutics. These advancements underscore the potential for integrating exosome-based therapies into clinical practice, heralding promise for future medical interventions.


Assuntos
Sistemas de Liberação de Medicamentos , Exossomos , Exossomos/metabolismo , Humanos , Sistemas de Liberação de Medicamentos/métodos , Animais , Portadores de Fármacos/química
18.
Appl Radiat Isot ; 207: 111250, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38457856

RESUMO

The purpose of this study is to evaluate the derived concentration guideline levels for unrestricted site reuse the Korea research reactor unit 1 and 2. Distribution coefficients for Co-60 and Sr-90 were derived, and site-specific values of the KRR soil were applied for the DCGLs for the seven target nuclide. The distribution coefficients of Co-60 and Sr-90 were 6,128 and 86.0 mL/g. The DCGLs derived from the dose by age group were 0.053 Bq/g for Co-60 and 45.0 Bq/g for H-3.

19.
ACS Biomater Sci Eng ; 10(1): 575-587, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38150627

RESUMO

Glioblastoma (GBM) is the deadliest tumor of the central nervous system, with a median survival of less than 15 months. Despite many trials, immune checkpoint-blocking (ICB) therapies using monoclonal antibodies against the PD-1/PD-L1 axis have demonstrated only limited benefits for GBM patients. Currently, the main hurdles in brain tumor therapy include limited drug delivery across the blood-brain barrier (BBB) and the profoundly immune-suppressive microenvironment of GBM. Thus, there is an urgent need for new therapeutics that can cross the BBB and target brain tumors to modulate the immune microenvironment. To this end, we developed an ICB strategy based on the BBB-permeable, 24-subunit human ferritin heavy chain, modifying the ferritin surface with 24 copies of PD-L1-blocking peptides to create ferritin-based ICB nanocages. The PD-L1pep ferritin nanocages first demonstrated their tumor-targeting and antitumor activities in an allograft colon cancer model. Next, we found that these PD-L1pep ferritin nanocages efficiently penetrated the BBB and targeted brain tumors through specific interactions with PD-L1, significantly inhibiting tumor growth in an orthotopic intracranial tumor model. The addition of PD-L1pep ferritin nanocages to triple in vitro cocultures of T cells, GBM cells, and glial cells significantly inhibited PD-1/PD-L1 interactions and restored T-cell activity. Collectively, these findings indicate that ferritin nanocages displaying PD-L1-blocking peptides can overcome the primary hurdle of brain tumor therapy and are, therefore, promising candidates for treating GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Ferritinas/uso terapêutico , Peptídeos/uso terapêutico , Microambiente Tumoral
20.
Small Methods ; : e2400038, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593365

RESUMO

Self-cleaning and anti-biofouling are both advantages for lotus-leaf-like superhydrophobic surfaces. Methods for creating superhydrophobicity, including chemical bonding low surface energy molecular fragments and constructing surface morphology with protrusions, micropores, and trapped micro airbags by traditional physical strategies, unfortunately, have encountered challenges. They often involve complex synthesis processes, stubborn chemical accumulation, brutal degradation, or infeasible calculation and imprecise modulation in fabricating hierarchical surface roughness. Here, a scalable method to prepare high-quality, breathable superhydrophobic membranes is proposed by developing a successive roll-to-roll laser manufacturing technique, which offers advantages over conventional fabrication approaches in enabling automatically large-scale production and ensuring cost-effectiveness. Nanosecond laser writing and femtosecond laser drilling produce surface microstructures and micropore arrays, respectively, endowing the membrane with superior antiwater capability with hierarchical microstructures forming a barrier and blocking water infiltration. The membrane's breathability is carefully optimized by tailoring micropore arrays to allow for the adequate passage of water vapor while maintaining superhydrophobicity. These membranes combine the benefits of anti-aqueous corrosive liquid behaviors, photothermal effects, thermoplastic properties, and stretchable performances as promising comprehensive materials in diverse scenes.

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