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1.
Proc Natl Acad Sci U S A ; 117(31): 18711-18718, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690697

RESUMO

KREMEN1 (KRM1) has been identified as a functional receptor for Coxsackievirus A10 (CV-A10), a causative agent of hand-foot-and-mouth disease (HFMD), which poses a great threat to infants globally. However, the underlying mechanisms for the viral entry process are not well understood. Here we determined the atomic structures of different forms of CV-A10 viral particles and its complex with KRM1 in both neutral and acidic conditions. These structures reveal that KRM1 selectively binds to the mature viral particle above the canyon of the viral protein 1 (VP1) subunit and contacts across two adjacent asymmetry units. The key residues for receptor binding are conserved among most KRM1-dependent enteroviruses, suggesting a uniform mechanism for receptor binding. Moreover, the binding of KRM1 induces the release of pocket factor, a process accelerated under acidic conditions. Further biochemical studies confirmed that receptor binding at acidic pH enabled CV-A10 virion uncoating in vitro. Taken together, these findings provide high-resolution snapshots of CV-A10 entry and identify KRM1 as a two-in-one receptor for enterovirus infection.


Assuntos
Proteínas do Capsídeo , Enterovirus Humano A , Proteínas de Membrana , Internalização do Vírus , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Enterovirus Humano A/química , Enterovirus Humano A/metabolismo , Células HEK293 , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Modelos Moleculares , Vírion/química , Vírion/metabolismo , Desenvelopamento do Vírus
2.
Acc Chem Res ; 53(8): 1545-1556, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32667182

RESUMO

Silica-based nanoparticles (SNPs) are a classic type of material employed in biomedical applications because of their excellent biocompatibility and tailorable physiochemical properties. Typically, SNPs are designed as nanocarriers for therapeutics delivery, which can address a number of intrinsic drawbacks of therapeutics, including limited bioavailability, short circulation lifetime, and unfavorable biodistribution. To improve the delivery efficiency and spatiotemporal precision, tremendous efforts have been devoted to engineering the physiochemical properties of SNPs, including particle size, morphology, and mesostructure, as well as conjugating targeting ligands and/or "gatekeepers" to endow improved cell selectivity and on demand release profiles. Despite significant progress, the biologically inert nature of the bare silica framework has largely restricted the functionalities of SNPs, rendering conventional SNPs mainly as nanocarriers for targeted delivery and controlled release. To meet the requirements of next generation nanomedicines with improved efficacy and precision, new insights on the relationship between the physiochemical properties of SNPs and their biological behavior are highly valuable. Meanwhile, a conceptual shift from a simple spatiotemporal control mechanism to a more sophisticated biochemistry and signaling pathway modulation would be of great importance.In this Account, an overview of our recent contribution to the field is presented, wherein SNPs with rationally designed nanostructures and nanochemistry are applied as nanocarriers (defined as "nanomaterials being used as a transport module for another substance" according to Wikipedia) and/or biomodulators (defined as "any material that modifies a biological response" according to Wiktionary). This Account encompasses two main sections. In the first section, we focus on the conventional nanocarriers concept with new insights on the design principles of the nanostructures. We present examples to demonstrate the engineering of pore geometry, surface topology, and asymmetry of nanoparticles to achieve enhanced drug, gene, and protein delivery efficiency. The contribution of surface roughness of SNPs on improving the cellular uptake efficiency, adhesion property, and DNA transfection capacity is particularly highlighted. In the second section, we discuss novel SNPs designed as biomodulators to regulate intracellular microenvironment and cell signaling, such as the oxidative stress and glutathione levels for improving the anticancer efficacy of therapeutics and mRNA transfection in specific cell lines. The interplay between the nanoparticles, biological system, and drugs is discussed. We further discuss how to engineer the composition of SNPs to modulate metal hemostasis to realize inherent anticancer activity. Two typical examples, including modulating copper signaling for tumor vasculature targeted therapy and controlling iron signaling for macrophage polarization based immunotherapy, are presented to highlight the unique advantages of SNPs as nanosized therapeutics in comparison to molecular drugs. Moreover, utilizing these two examples, we showcase the possibility of designing SNPs with intrinsic pharmaceutical activity to indirectly control tumor growth without inducing significant cytotoxicity, thus alleviating the biosafety concerns of nanomedicines. At the end of this Account, we discuss our personal perspectives on the promises, opportunities, and issues in engineered SNPs as nanocarriers as well as their transition toward biomodulators. With a major focus on the latter scenario, the current status and possible future directions are outlined.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Dióxido de Silício/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Polaridade Celular/efeitos dos fármacos , Morte Celular Imunogênica/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Nanomedicina , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Proteínas/química , Proteínas/metabolismo , Células RAW 264.7 , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Propriedades de Superfície
3.
Biochem Biophys Res Commun ; 518(2): 246-252, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31416616

RESUMO

Nel-like molecule 1 (Nell-1) is an essential positive regulator of tooth development and odontoblast differentiation. However, its precise mechanism remains undetermined. This study aims to explore the possible receptor or binding protein of Nell-1. Results showed that Nell-1 and Apoptosis related protein 3(APR3) expression levels were high in odontoblasts and inversely correlated. Endogenous Nell-1 co-immunoprecipitated with APR3, and this co-IP was reciprocal. Double immunofluorescence staining revealed that Nell-1 and APR3 colocalized on the nuclear envelope of human dental pulp cells. Nell-1 inhibited the proliferation of these cells co-infected with APR3 through Cyclin D1 downregulation. The interaction of Nell-1 with APR3 stimulated alkaline phosphatase (ALP) activity and promoted the expression and mineralization of DSPP, ALP, OPN, and BSP. The shRNA of APR3 decreased cell differentiation and mineralization. Nell-1 could reciprocally interact with APR3 and stimulate the differentiation and mineralization of human dental pulp cells. Future studies should explore the potential functional connection and the molar mechanism of such interaction.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Polpa Dentária/citologia , Odontoblastos/citologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Polpa Dentária/metabolismo , Humanos , Proteínas de Membrana Transportadoras , Odontoblastos/metabolismo , Odontogênese , Mapas de Interação de Proteínas
4.
Cytotherapy ; 20(5): 670-686, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29576501

RESUMO

BACKGROUND: This study explored the neural differentiation and therapeutic effects of stem cells from human exfoliated deciduous teeth (SHED) in a rat model of Parkinson's disease (PD). METHODS: The SHED were isolated from fresh dental pulp and were induced to differentiate to neurons and dopamine neurons by inhibiting similar mothers against dpp (SMAD) signaling with Noggin and increase conversion of dopamine neurons from SHED with CHIR99021, Sonic Hedgehog (SHH) and FGF8 in vitro. The neural-primed SHED were transplanted to the striatum of 6-hydroxydopamine (6-OHDA)-induced PD rats to evaluate their neural differentiation and functions in vivo. RESULTS: These SHED were efficiently differentiated to neurons (62.7%) and dopamine neurons (42.3%) through a newly developed method. After transplantation, the neural-induced SHED significantly improved recovery of the motor deficits of the PD rats. The grafted SHED were differentiated into neurons (61%), including dopamine neurons (22.3%), and integrated into the host rat brain by forming synaptic connections. Patch clamp analysis showed that neurons derived from grafted SHED have the same membrane potential profile as dopamine neurons, indicating these cells are dopamine neuron-like cells. The potential molecular mechanism of SHED transplantation in alleviating motor deficits of the rats is likely to be mediated by neuronal replacement and immune-modulation as we detected the transplanted dopamine neurons and released immune cytokines from SHED. CONCLUSION: Using neural-primed SHED to treat PD showed significant restorations of motor deficits in 6-OHDA-induced rats. These observations provide further evidence that SHED can be used for cell-based therapy of PD.


Assuntos
Corpo Estriado/transplante , Atividade Motora , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Transplante de Células-Tronco , Células-Tronco/citologia , Esfoliação de Dente/patologia , Dente Decíduo/citologia , Animais , Comportamento Animal , Diferenciação Celular , Sobrevivência Celular , Criança , Pré-Escolar , Citocinas/metabolismo , Neurônios Dopaminérgicos/citologia , Humanos , Masculino , Oxidopamina , Ratos Wistar
5.
J Am Chem Soc ; 139(18): 6321-6328, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28440642

RESUMO

Asymmetric mesoporous silica nanoparticles (MSNs) with controllable head-tail structures have been successfully synthesized. The head particle type is tunable (solid or porous), and the tail has dendritic large pores. The tail length and tail coverage on head particles are adjustable. Compared to spherical silica nanoparticles with a solid structure (Stöber spheres) or large-pore symmetrical MSNs with fully covered tails, asymmetrical head-tail MSNs (HTMSNs) show superior hemocompatibility due to reduced membrane deformation of red blood cells and decreased level of reactive oxygen species. Moreover, compared to Stöber spheres, asymmetrical HTMSNs exhibit a higher level of uptake and in vitro maturation of immune cells including dendritic cells and macrophage. This study has provided a new family of nanocarriers with potential applications in vaccine development and immunotherapy.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Portadores de Fármacos/química , Humanos , Macrófagos/imunologia , Estrutura Molecular , Tamanho da Partícula , Porosidade , Dióxido de Silício/síntese química , Propriedades de Superfície
6.
Croat Med J ; 57(5): 474-481, 2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27815938

RESUMO

AIM: To prove whether real-time three-dimensional (3D) ultrasound with live xPlane imaging is better in observing fetal movements than standard ultrasound imaging. METHODS: 50 healthy women with singleton pregnancies (22-43 years old) at 11 to 14 weeks of gestation underwent real-time 3D ultrasound examination with live xPlane imaging from July 2014 to February 2015. The incidence and frequency of 10 fetal movement patterns in 10 minutes were evaluated, including general movements (GMs), isolated arm movements, isolated leg movements, hiccup, stretching, breathing, startle, jaw opening, isolated head retroflexion, and isolated head anteflexion. The correlation between gestational age and frequency of each fetal movement pattern was analyzed. RESULTS: GM had the highest incidence (100%), followed by startle (84%) and isolated arm movements (68%). Their median frequency was 5 (IQR 3-6), 5 (IQR 1.75-11.5), and 1 (IQR 0-2), respectively. GM (Z=5.875, P<0.001) and startle (Z=5.302, P<0.001) had significantly higher frequency than isolated arm movements. The other 7 fetal movement patterns had much lower incidence and frequency. The frequency of GM was positively correlated with gestational age (r=0.360, P=0.010). CONCLUSION: Real-time 3D ultrasound with live x Plane imaging was shown to be a feasible tool for observing fetal movements.


Assuntos
Movimento Fetal , Imageamento Tridimensional/métodos , Primeiro Trimestre da Gravidez , Ultrassonografia Pré-Natal/métodos , Adulto , Feminino , Idade Gestacional , Humanos , Imageamento Tridimensional/instrumentação , Gravidez
7.
J Craniofac Surg ; 25(6): 2112-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25304145

RESUMO

OBJECTIVE: The aim of this study was to compare the disc positions and condylar changes induced by different stretching forces in the modified animal model for anterior disc displacement (ADD) of the temporomandibular joint. METHODS: In the experimental group, 30 rabbits were equally divided into 3 subgroups and underwent surgical ADD via different stretching forces: group A with 0.5 N, group B with 1 N, and group C with 2 N. In the sham group, 6 rabbits underwent the same surgery without the disc being pulled anteriorly. The diagnosis of ADD was made when the anterior band of the disc was located anteriorly to the articular eminence. Histologic and radiographic changes of the condyles were observed under light microscopy and micro-computed tomography scanning 1 week after surgery. RESULTS: The success rates of ADD were both 100% in groups B and C and 70% in group A. The correlations between the stretching force and severity of ADD, the stretching force and severity of cartilage changes, and the severity of ADD and cartilage changes were statistically significant (P < 0.01). The most advanced ADD and severest condylar changes were induced in group C. Condylar remodeling and scleroses were found in micro-computed tomography scans. CONCLUSIONS: The rabbit model for ADD has been successfully established in this study, which is feasible and minimally invasive. The stretching force of at least 1 N could induce the disc displaced successfully. Larger stretching force would induce severer ADD and condylar degenerative changes.


Assuntos
Luxações Articulares/patologia , Côndilo Mandibular/patologia , Disco da Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/patologia , Animais , Fenômenos Biomecânicos , Remodelação Óssea/fisiologia , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Modelos Animais de Doenças , Côndilo Mandibular/diagnóstico por imagem , Osteosclerose/diagnóstico por imagem , Osteosclerose/patologia , Coelhos , Distribuição Aleatória , Estresse Mecânico , Osso Temporal/diagnóstico por imagem , Osso Temporal/patologia , Disco da Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Microtomografia por Raio-X/métodos
8.
Bioresour Technol ; 403: 130764, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38718903

RESUMO

Abundant renewable resource lignocellulosic biomass possesses tremendous potential for green biomanufacturing, while its efficient utilization by Yarrowia lipolytica, an attractive biochemical production host, is restricted since the presence of inhibitors furfural and acetic acid in lignocellulosic hydrolysate. Given deficient understanding of inherent interactions between inhibitors and cellular metabolism, sufficiently mining relevant genes is necessary. Herein, 14 novel gene targets were discovered using clustered regularly interspaced short palindromic repeats interference library in Y. lipolytica, achieving tolerance to 0.35 % (v/v) acetic acid (the highest concentration reported in Y. lipolytica), 4.8 mM furfural, or a combination of 2.4 mM furfural and 0.15 % (v/v) acetic acid. The tolerance mechanism might involve improvement of cell division and decrease of reactive oxygen species level. Transcriptional repression of effective gene targets still enabled tolerance when xylose was a carbon source. This work forms a robust foundation for improving microbial tolerance to lignocellulose-derived inhibitors and revealing underlying mechanism.


Assuntos
Ácido Acético , Furaldeído , Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Furaldeído/farmacologia , Ácido Acético/farmacologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Lignina/metabolismo , Genoma Fúngico , Biblioteca Gênica
9.
MedComm (2020) ; 5(6): e587, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840773

RESUMO

Human enterovirus A71 (EV-A71) is a significant etiological agent responsible for epidemics of hand, foot, and mouth disease (HFMD) in Asia-Pacific regions. There are presently no licensed antivirals against EV-A71, and the druggable target for EV-A71 remains very limited. The phenotypic hit 10,10'-bis(trifluoromethyl) marinopyrrole A derivative, herein termed MPA-CF3, is a novel potent small-molecule inhibitor against EV-A71, but its pharmacological target(s) and antiviral mechanisms are not defined. Here, quantitative chemoproteomics deciphered the antiviral target of MAP-CF3 as host factor coatomer subunit zeta-1 (COPZ1). Mechanistically, MPA-CF3 disrupts the interaction of COPZ1 with the EV-A71 nonstructural protein 2C by destabilizing COPZ1 upon binding. The destruction of this interaction blocks the coatomer-mediated transport of 2C to endoplasmic reticulum, and ultimately inhibits EV-A71 replication. Taken together, our study disclosed that MPA-CF3 can be a structurally novel host-targeting anti-EV-A71 agent, providing a structural basis for developing the COPZ1-targeting broad-spectrum antivirals against enteroviruses. The mechanistic elucidation of MPA-CF3 against EV-A71 may offer an alternative COPZ1-involved therapeutic pathway for enterovirus infection.

10.
Waste Manag ; 182: 44-54, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636125

RESUMO

Pyrolysis can effectively convert waste tires into high-value products. However, the sulfur-containing compounds in pyrolysis oil and gas would significantly reduce the environmental and economic feasibility of this technology. Here, the desulfurization and upgrade of waste tire pyrolysis oil and gas were performed by adding different metal oxides (Fe2O3, CuO, and CaO). Results showed that Fe2O3 exhibited the highest removal efficiency of 87.7 % for the sulfur-containing gas at 600 °C with an outstanding removal efficiency of 99.5 % for H2S. CuO and CaO were slightly inferior to Fe2O3, with desulfurization efficiencies of 75.9 % and 45.2 % in the gas when added at 5 %. Fe2O3 also demonstrated a notable efficacy in eliminating benzothiophene, the most abundant sulfur compound in pyrolysis oil, with a removal efficiency of 78.1 %. Molecular dynamics simulations and experiments showed that the desulfurization mechanism of Fe2O3 involved the bonding of Fe-S, the breakage of C-S, dehydrogenation and oxygen migration process, which promoted the conversion of Fe2O3 to FeO, FeS and Fe2(SO4)3. Meanwhile, Fe2O3 enhanced the cyclization and dehydrogenation reaction, facilitating the upgrade of oil and gas (monocyclic aromatics to 57.4 % and H2 to 22.3 %). This study may be helpful for the clean and high-value conversion of waste tires.


Assuntos
Óxidos , Pirólise , Óxidos/química , Enxofre/química , Incineração/métodos , Compostos Férricos/química , Gases/química , Borracha/química , Compostos de Cálcio/química , Cobre
11.
Genes (Basel) ; 14(1)2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36672951

RESUMO

The enigmatic scaphopods, or tusk shells, are a small and rare group of molluscs whose phylogenomic position among the Conchifera is undetermined, and the taxonomy within this class also needs revision. Such work is hindered by there only being a very few mitochondrial genomes in this group that are currently available. Here, we present the assembly and annotation of the complete mitochondrial genome from Dentaliida Pictodentalium vernedei, whose mitochondrial genome is 14,519 bp in size, containing 13 protein-coding genes, 22 tRNA genes and two rRNA genes. The nucleotide composition was skewed toward A-T, with a 71.91% proportion of AT content. Due to the mitogenome-based phylogenetic analysis, we defined P. vernedei as a sister to Graptacme eborea in Dentaliida. Although a few re-arrangements occurred, the mitochondrial gene order showed deep conservation within Dentaliida. Yet, such a gene order in Dentaliida largely diverges from Gadilida and other molluscan classes, suggesting that scaphopods have the highest degree of mitogenome arrangement compared to other molluscs.


Assuntos
Genoma Mitocondrial , Animais , Filogenia , Ordem dos Genes , Moluscos/genética , Mitocôndrias/genética
12.
Int J Implant Dent ; 9(1): 48, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38055096

RESUMO

PURPOSE: This systematic review aimed to investigate the accuracy of intraoral scan (IOS) impressions of implant-supported restorations in in vivo studies. METHODS: A systematic electronic search and review of studies on the accuracy of IOS implant impressions were conducted to analyze the peer-reviewed literature published between 1989 and August 2023. The bias analysis was performed by two reviewers. Data on the study characteristics, accuracy outcomes, and related variables were extracted. A meta-analysis of randomized control trials was performed to investigate the impact of IOS on peri-implant crestal bone loss and the time involved in the impression procedure. RESULTS: Ten in vivo studies were included in this systematic review for final analysis. Six studies investigated the trueness of IOS impressions, but did not reach the same conclusions. One study assessed the precision of IOS impressions for a single implant. Four clinical studies examined the accuracy of IOS implant impressions with a follow-up of 1-2 years. In full arches, IOS impression procedure needed significantly less time than conventional one (mean difference for procedure time was 8.59 min [6.78, 10.40 min], P < 0.001), prosthetic survival rate was 100%, and marginal bone levels of all participants could be stably maintained (mean difference in marginal bone loss at 12 months was 0.03 mm [-0.08, 0.14 mm], P = 0.55). CONCLUSIONS: The accuracy of IOS impressions of implant-supported restorations varied greatly depending on the scanning strategy. The trueness and precision of IOS in the partial and complete arches remain unclear and require further assessment. Based on follow-up clinical studies, IOS impressions were accurate in clinical practice. However, these results should be interpreted with caution, as some evidences are obtained from the same research group.


Assuntos
Doenças Ósseas Metabólicas , Implantes Dentários , Humanos , Projetos de Pesquisa , Hematopoiese Clonal , Eletrônica
13.
Sci Total Environ ; 904: 166595, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659546

RESUMO

Organic-rich thin stillage is a significant by-product of the liquor brewing industry, and its direct release into the environment can cause severe water pollution. Microbial fuel cells (MFCs) offer the possibility for converting organic matters in thin stillage into clean electricity. However, limited biofilm formation and conductivity are crucial bottlenecks in restricting the power harvest of MFCs. Here, to efficiently harvest electricity power from thin stillage of liquor industry, we adopted a modular engineering strategy to increase biofilm formation and conductivity of Shewanella oneidensis via enhancing the component biosynthesis of extracellular polymer substrates (EPS) matrix, regulating intracellular c-di-GMP level, and constructing of artificial hybrid system. The results showed that the constructed CNTs@CF-EnBF2 hybrid system with low charge-transfer resistance enabled a maximum output power density of 576.77 mW/m2 in lactate-fed MFCs. Also, to evaluate the capability of harvesting electricity from actual wastewater, the CNTs@CF-EnBF2 system was employed to treat actual thin stillage, obtaining a maximum output power density of 495.86 mW/m2, 3.3-fold higher than the wild-type strain. Our research suggested that engineering and regulating EPS biosynthesis effectively promoted bioelectricity harvest, providing a green and sustainable treatment strategy for thin stillage.


Assuntos
Fontes de Energia Bioelétrica , Nanotubos de Carbono , Fibra de Carbono , Eletricidade , Eletrodos , Biofilmes
14.
Int J Stem Cells ; 16(1): 93-107, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36042010

RESUMO

Background and Objectives: Chronic periodontitis can lead to alveolar bone resorption and eventually tooth loss. Stem cells from exfoliated deciduous teeth (SHED) are appropriate bone regeneration seed cells. To track the survival, migration, and differentiation of the transplanted SHED, we used super paramagnetic iron oxide particles (SPIO) Molday ION Rhodamine-B (MIRB) to label and monitor the transplanted cells while repairing periodontal bone defects. Methods and Results: We determined an appropriate dose of MIRB for labeling SHED by examining the growth and osteogenic differentiation of labeled SHED. Finally, SHED was labeled with 25 µg Fe/ml MIRB before being transplanted into rats. Magnetic resonance imaging was used to track SHED survival and migration in vivo due to a low-intensity signal artifact caused by MIRB. HE and immunohistochemical analyses revealed that both MIRB-labeled and unlabeled SHED could promote periodontal bone regeneration. The colocalization of hNUC and MIRB demonstrated that SHED transplanted into rats could survive in vivo. Furthermore, some MIRB-positive cells expressed the osteoblast and osteocyte markers OCN and DMP1, respectively. Enzyme-linked immunosorbent assay revealed that SHED could secrete protein factors, such as IGF-1, OCN, ALP, IL-4, VEGF, and bFGF, which promote bone regeneration. Immunofluorescence staining revealed that the transplanted SHED was surrounded by a large number of host-derived Runx2- and Col II-positive cells that played important roles in the bone healing process. Conclusions: SHED could promote periodontal bone regeneration in rats, and the survival of SHED could be tracked in vivo by labeling them with MIRB. SHED are likely to promote bone healing through both direct differentiation and paracrine mechanisms.

15.
J Colloid Interface Sci ; 628(Pt B): 297-305, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998455

RESUMO

Cellular delivery of DNA using silica nanoparticles has attracted great attention. Typically, polyethyleneimine (PEI) is used to form a silica/PEI composite vector. Understanding the interactions at the silica and PEI interface is important for successful DNA delivery and transfection, especially for silica with different surface functionality. Herein, we report that a higher content of hydrogen boning formed between PEI molecules and phosphonate modified silica nanoparticles could slow down the PEI dissolution from the freeze-dried solid composites into aqueous solution than the bare silica counterpart. The pronounced PEI retention ability through phosphonation of silica nanoparticles effectively improves the transfection efficiency due to the high DNA binding affinity extracellularly, effective lysosome escape and high nuclear entry of both PEI and DNA intracellularly. Our study provides a fundamental understanding on designing effective silica-PEI-based nano-vectors for DNA delivery applications.


Assuntos
Nanopartículas , Organofosfonatos , Polietilenoimina/química , Dióxido de Silício/química , Nanopartículas/química , Transfecção , DNA/metabolismo , Hidrogênio
16.
J Pharm Sci ; 111(2): 450-457, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34547305

RESUMO

Epidermal growth factor receptor (EGFR) is an efficient target for cancer therapy. In this study, a high-affinity EGFR-antagonistic affibody (ZEGFR) molecule coupled with cisplatin-loaded PEGylated liposomes (LS-DDP) was applied to actively target EGFR+ A431 tumor cells in vitro and in vivo. The LS-DDP coupled with ZEGFR (AS-DDP) had an average size of 140.01 ± 0.84 nm, low polydispersity, a zeta potential of -13.40 ± 0.8 mV, an acceptable encapsulation efficiency of 17.30 ± 1.35%, and released cisplatin in a slow-controlled manner. In vitro, AS-DDP demonstrated a higher amount of platinum intracellular uptake by A431 cells than LS-DDP. The IC50 value of AS-DDP (9.02 ± 1.55 µg/ml) was much lower than that of LS-DDP (16.44 ± 0.87 µg/ml), indicating that the anti-tumor effects of AS-DDP were remarkable due to the modification of ZEGFR. In vivo, the concentration of AS-DDP in the tumor site increased more than 1.76-fold, while an increase in apoptotic cells at 48 h compared to the LS-DDP was also observed, illustrating that AS-DDP possessed excellent tumor-targeting efficiency. As a result, the targeted nano-liposomes achieved greater tumor suppression. Therefore, selective targeting of LS-DDP coupled with ZEGFR enhanced the anti-tumor effects and appeared to be a promising strategy for the treatment of EGFR+ tumors.


Assuntos
Antineoplásicos , Cisplatino , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Receptores ErbB/metabolismo , Humanos , Lipossomos
17.
Water Res ; 219: 118553, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35561622

RESUMO

Shewanella oneidensis MR-1 is an attractive model microbe for elucidating the biofilm-metal interactions that contribute to the billions of dollars in corrosion damage to industrial applications each year. Multiple mechanisms for S. oneidensis-enhanced corrosion have been proposed, but none of these mechanisms have previously been rigorously investigated with methods that rule out alternative routes for electron transfer. We found that S. oneidensis grown under aerobic conditions formed thick biofilms (∼50 µm) on stainless steel coupons, accelerating corrosion over sterile controls. H2 and flavins were ruled out as intermediary electron carriers because stainless steel did not reduce riboflavin and previous studies have demonstrated stainless does not generate H2. Strain ∆mtrCBA, in which the genes for the most abundant porin-cytochrome conduit in S. oneidensis were deleted, corroded stainless steel substantially less than wild-type in aerobic cultures. Wild-type biofilms readily reduced nitrate with stainless steel as the sole electron donor under anaerobic conditions, but strain ∆mtrCBA did not. These results demonstrate that S. oneidensis can directly consume electrons from iron-containing metals and illustrate how direct metal-to-microbe electron transfer can be an important route for corrosion, even in aerobic environments.


Assuntos
Elétrons , Aço Inoxidável , Biofilmes , Corrosão , Transporte de Elétrons , Metais , Oxirredução , Aço
18.
Sheng Wu Gong Cheng Xue Bao ; 37(1): 1-14, 2021 Jan 25.
Artigo em Zh | MEDLINE | ID: mdl-33501785

RESUMO

Microbial fuel cell (MFC) is a bioelectrochemical device, that enables simultaneous wastewater treatment and energy generation. However, a few issues such as low output power, high ohmic internal resistance, and long start-up time greatly limit MFCs' applications. MFC anode is the carrier of microbial attachment, and plays a key role in the generation and transmission of electrons. High-quality bioelectrodes have developed into an effective way to improve MFC performance. Conjugated polymers have advantages of low cost, high conductivity, chemical stability and good biocompatibility. The use of conjugated polymers to modify bioelectrodes can achieve a large specific surface area and shorten the charge transfer path, thereby achieving efficient biological electrochemical performance. In addition, bacteria can be coated with nano-scale conjugated polymer and effectively transfer the electrons generated by cells to electrodes. This article reviews the recently reported applications of conjugated polymers in microbial fuel cells, focusing on the MFC anode materials modified by conjugated polymers. This review also systematically analyzes the advantages and limitations of conjugated polymers, and how these composite hybrid bioelectrodes solve practical issues such as low energy output, high inner resistance, and long starting time.


Assuntos
Fontes de Energia Bioelétrica , Purificação da Água , Bactérias , Eletricidade , Eletrodos , Polímeros
19.
ACS Appl Mater Interfaces ; 13(43): 50695-50704, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34664946

RESUMO

Asymmetric mesoporous silica nanoparticles (AMSNs) with one side featuring a spiky nanotopography, while the other side is smooth and solid, were synthesized via an ethylenediamine (EDA)-directed silica-polymer cooperative assembly approach. By simply varying the EDA amount (x), AMSNs-x samples with adjustable spiky surface coverage were obtained. It is demonstrated that a spiky coverage higher than 50% improved the hemocompatibility of AMSN-x, possibly due to the reduced contact area of the smooth side exposed to the red blood cell (RBC) membrane. Moreover, AMSNs-175 and AMSNs-200 with high spiky coverage enhanced their plasmid DNA (pDNA) loading and binding capability, as well as cellular uptake into HEK-293T cells, thus resulting in high transfection performance. The good hemocompatibility and high performance in pDNA delivery of AMSNs-x with high spiky coverage allow them to serve as promising nonviral vectors for potential applications in gene therapies and DNA vaccines.


Assuntos
Materiais Biocompatíveis/química , Técnicas de Transferência de Genes , Nanopartículas/química , Polímeros/química , Dióxido de Silício/química , Materiais Biocompatíveis/síntese química , Membrana Celular/química , DNA/química , Eritrócitos/química , Etilenodiaminas/química , Células HEK293 , Humanos , Tamanho da Partícula , Plasmídeos , Polímeros/síntese química , Porosidade , Propriedades de Superfície
20.
Transl Cancer Res ; 10(6): 2747-2754, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35116585

RESUMO

BACKGROUND: The purpose of the present study was to investigate the clinicopathological characteristics and prognostic factors of second primary oral squamous cell carcinoma after radiotherapy for head and neck cancer. METHODS: The clinicopathological characteristics of 48 second primary oral squamous cell carcinoma patients with a history of radiotherapy for head and neck cancer were retrospectively analyzed by Kaplan-Meier survival analysis and Cox proportional hazards model, including gender, age, alcohol consumption, smoking, clinical stage, margin status, regional lymph node status, tumor differentiation and treatment mode. RESULTS: The second primary oral squamous cell carcinoma mostly occurred on the tongue [18/48], buccal [12/48] and gingiva [10/48], and the 3- and 5-year overall survival (OS) was 60.3% and 39.4%, respectively. Margin status and extranodal extension were significantly associated with OS, while only margin status was found to be an independent prognostic factor of OS in the Cox proportional hazards model (P=0.003, HR =3.976, 95% CI: 1.596-9.904). CONCLUSIONS: Oral squamous cell carcinoma patients underwent radiotherapy for head and neck cancer show poor survival outcomes. Margin status is an independent prognostic factor of second primary oral squamous cell carcinoma.

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