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1.
Small ; : e2311498, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377274

RESUMO

Fiber crossbars, an emerging electronic device, have become the most promising basic unit for advanced smart textiles. The demand for highly sensitive fiber crossbar sensors (FCSs) in wearable electronics is increased. However, the unique structure of FCSs presents challenges in replicating existing sensitivity enhancement strategies. Aiming at the sensitivity of fiber crossbar sensors, a second-order synergistic strategy is proposed that combines air capacitance and equipotential bodies, resulting in a remarkable sensitivity enhancement of over 20 times for FCSs. This strategy offers a promising avenue for the design and fabrication of FCSs that do not depend on intricate microstructures. Furthermore, the integrative structure of core-sheath fibers ensures a robust interface, leading to a low hysteresis of only 2.33% and exceptional stability. The outstanding capacitive response performance of FCSs allows them to effectively capture weak signals such as pulses and sounds. This capability opens up possibilities for the application of FCSs in personalized health management, as demonstrated by wireless monitoring systems based on pulse signals.

2.
Med Sci Monit ; 27: e930974, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34315845

RESUMO

BACKGROUND The aim of this study was to explore the potential impact of pyloric stenosis (PS) on the nutritional status, the incidence of postoperative complications, and the long-term prognosis of distal gastric cancer (GC) patients after curative resection. MATERIAL AND METHODS We retrospectively analyzed the data of 343 GC patients who underwent curative gastrectomy for gastric cancer between January 2010 and December 2013. All patients were divided into 2 groups according to the status of PS. Their clinical and pathological features, nutritional indicators, and incidence of postoperative complications were compared and potential prognostic factors were analyzed using the propensity score matching analysis (PSM). RESULTS Seventy-four (21.6%) patients had PS. Patients with PS had worse survival outcomes than those without PS (χ²=21.369, P<0.001). Multivariate survival analysis demonstrated that PS, depth of invasion, and lymph node metastasis (all P<0.05) were the independent predictors of overall survival (OS). Patients with PS had significantly higher lymph node metastasis in No. 3, 4sb, 4d, 6, 8a, 9, and 14v lymph nodes. Patients with PS had significantly lower preoperative BMI, more weight loss, and lower prealbumin than those without PS. There were no significant differences between the 2 groups in postoperative complications, morbidity, or mortality. CONCLUSIONS Distal GC patients with PS have poor clinicopathological and nutritional status and poor prognosis. However, PS does not increase surgery-related morbidity and mortality.


Assuntos
Gastrectomia/métodos , Estado Nutricional , Período Pré-Operatório , Estenose Pilórica/complicações , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Estômago/cirurgia , Análise de Sobrevida , Resultado do Tratamento
3.
Anal Chem ; 92(11): 7690-7698, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32392405

RESUMO

The present project studied the signal drift in liquid chromatography tandem mass spectrometry (LC-MS/MS) and proposed a strategy for compensating such drift. In the study, four 4-component groups were repeatedly run on different LC-MS/MS systems for over 12 h to investigate the dependence of signal drift on time and hardware systems. The 4-component groups each consisted of (1) an analyte, (2) a stable isotope labeled analyte, (3) a compound with similar structure to the analyte, and (4) a compound with dissimilar structure. All of the species showed significant signal drift, generally more than 25% over 12 h. The analyte and its stable isotope labeled analog always have the same drifting pattern including the trends and direction from one LC-MS/MS system to another. Signal drift was also found to be concentration dependent. Our experiments further proved that a conventional stable isotope labeled internal standard in LC-MS/MS quantification would not compensate the variations caused by concentration-dependent signal drift. An ideal internal standard for LC-MS/MS has both identical structure and similar concentration to the analyte. For that, we proposed a new internal standard strategy, pseudo internal standard (Pseudo IS), for LC-MS/MS quantification. Pseudo IS could effectively compensate signal drift in spite of its significant time, system, and concentration dependencies.

4.
Virus Genes ; 56(3): 354-360, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32198605

RESUMO

Seven strains of porcine reproductive and respiratory syndrome virus (PRRSV) were isolated from 2014 to 2017 in the Shandong province of China and their genomes were sequenced and analyzed. Results showed that all seven of the isolates belong to PRRSV 2, and are clustered into four lineages (lineage 1, 3, 5 and 8) based on comparisons of the ORF5 gene. Comparative analysis of genomes and specific amino acid sites revealed that three of the strains (SDwh1402, SDwh1602 and SDwh1701) have evolved directly from modified live virus (MLV) JXA1-P80, TJM-F92 and IngelvacPRRS. Further recombination analysis revealed that two of the strains (SDyt1401 and SDwh1601) were the result of a recombination event between MLVs JXA1-P80 and NADC30 while two other strains (SDwh1403 and SDqd1501) were the result of recombination between MLVs IngelvacPRRS and NADC30 and HP-PRRSV and QYYZ, respectively. Our results add to the data on MLV evolution and PRRSV recombination and provide a better understanding of the epidemiology of PRRSV in China.


Assuntos
Evolução Molecular , Variação Genética , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Recombinação Genética , Animais , China/epidemiologia , Genoma Viral , Genômica/métodos , Filogenia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Suínos
5.
Virus Genes ; 56(5): 673, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32594295

RESUMO

The original version of this article unfortunately contained an error in GenBank Accession Number.

6.
J Cell Biochem ; 119(11): 8872-8886, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30076626

RESUMO

Human mesenchymal stem cells (MSCs) are a heterogeneous subset of nonhematopoietic multipotent stromal stem cells and can differentiate into mesodermal lineage, such as adipocytes, osteocytes, and chondrocytes, as well as ectodermal and endodermal lineages. Human umbilical cord (UC) is one of the most promising sources of MSCs. However, the molecular and cellular characteristics of UC-derived MSCs (UC-MSCs) require extensive investigations, which are hampered by the limited lifespan and the diminished potency over passages. Here, we used the piggyBac transposon-based simian virus 40 T antigen (SV40T) immortalization system and effectively immortalized UC-MSCs, yielding the iUC-MSCs. A vast majority of the immortalized lines are positive for MSC markers but not for hematopoietic markers. The immortalization phenotype of the iUC-MSCs can be effectively reversed by flippase recombinase-induced the removal of SV40T antigen. While possessing long-term proliferation capability, the iUC-MSCs are not tumorigenic in vivo. Upon bone morphogenetic protein 9 (BMP9) stimulation, the iUC-MSC cells effectively differentiate into osteogenic, chondrogenic, and adipogenic lineages both in vitro and in vivo, which is indistinguishable from that of primary UC-MSCs, indicating that the immortalized UC-MSCs possess the characteristics similar to that of their primary counterparts and retain trilineage differentiation potential upon BMP9 stimulation. Therefore, the engineered iUC-MSCs should be a valuable alternative cell source for studying UC-MSC biology and their potential utilities in immunotherapies and regenerative medicine.


Assuntos
Adipogenia/fisiologia , Diferenciação Celular/fisiologia , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteogênese/fisiologia , Cordão Umbilical/citologia , Análise de Variância , Animais , Antígenos Transformantes de Poliomavirus/metabolismo , Técnicas de Cultura de Células/métodos , Proliferação de Células , Condrogênese/fisiologia , Feminino , Vetores Genéticos , Células HEK293 , Humanos , Recém-Nascido , Camundongos Nus , Transposon Resolvases/metabolismo
7.
J Cell Mol Med ; 21(11): 2782-2795, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28470873

RESUMO

The cranial suture complex is a heterogeneous tissue consisting of osteogenic progenitor cells and mesenchymal stem cells (MSCs) from bone marrow and suture mesenchyme. The fusion of cranial sutures is a highly coordinated and tightly regulated process during development. Craniosynostosis is a congenital malformation caused by premature fusion of cranial sutures. While the progenitor cells derived from the cranial suture complex should prove valuable for studying the molecular mechanisms underlying suture development and pathogenic premature suture fusion, primary human cranial suture progenitors (SuPs) have limited life span and gradually lose osteoblastic ability over passages. To overcome technical challenges in maintaining sufficient and long-term culture of SuPs for suture biology studies, we establish and characterize the reversibly immortalized human cranial suture progenitors (iSuPs). Using a reversible immortalization system expressing SV40 T flanked with FRT sites, we demonstrate that primary human suture progenitor cells derived from the patent sutures of craniosynostosis patients can be efficiently immortalized. The iSuPs maintain long-term proliferative activity, express most of the consensus MSC markers and can differentiate into osteogenic and adipogenic lineages upon BMP9 stimulation in vitro and in vivo. The removal of SV40 T antigen by FLP recombinase results in a decrease in cell proliferation and an increase in the endogenous osteogenic and adipogenic capability in the iSuPs. Therefore, the iSuPs should be a valuable resource to study suture development, intramembranous ossification and the pathogenesis of craniosynostosis, as well as to explore cranial bone tissue engineering.


Assuntos
Suturas Cranianas/metabolismo , Craniossinostoses/genética , Efeito Fundador , Fatores de Diferenciação de Crescimento/genética , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Adipócitos/citologia , Adipócitos/metabolismo , Diferenciação Celular , Linhagem Celular Transformada , Proliferação de Células , Suturas Cranianas/patologia , Craniossinostoses/metabolismo , Craniossinostoses/patologia , Expressão Gênica , Fator 2 de Diferenciação de Crescimento , Fatores de Diferenciação de Crescimento/metabolismo , Humanos , Lactente , Masculino , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteoblastos/metabolismo , Vírus 40 dos Símios/genética , Vírus 40 dos Símios/metabolismo , Transformação Genética
8.
Cell Physiol Biochem ; 41(2): 484-500, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28214873

RESUMO

BACKGROUND: BMP9 induces both osteogenic and adipogenic differentiation of mesenchymal stem cells (MSCs). Nell1 is a secretory glycoprotein with osteoinductive and anti-adipogenic activities. We investigated the role of Nell1 in BMP9-induced osteogenesis and adipogenesis in MSCs. METHODS: Previously characterized MSCs iMEFs were used. Overexpression of BMP9 and NELL1 or silencing of mouse Nell1 was mediated by adenoviral vectors. Early and late osteogenic and adipogenic markers were assessed by staining techniques and qPCR analysis. In vivo activity was assessed in an ectopic bone formation model of athymic mice. RESULTS: We demonstrate that Nell1 expression was up-regulated by BMP9. Exogenous Nell1 potentiated BMP9-induced late stage osteogenic differentiation while inhibiting the early osteogenic marker. Forced Nell1 expression enhanced BMP9-induced osteogenic regulators/markers and inhibited BMP9-upregulated expression of adipogenic regulators/markers in MSCs. In vivo ectopic bone formation assay showed that exogenous Nell1 expression enhanced mineralization and maturity of BMP9-induced bone formation, while inhibiting BMP9-induced adipogenesis. Conversely, silencing Nell1 expression in BMP9-stimulated MSCs led to forming immature chondroid-like matrix. CONCLUSION: Our findings indicate that Nell1 can be up-regulated by BMP9, which in turn accelerates and augments BMP9-induced osteogenesis. Exogenous Nell1 may be exploited to enhance BMP9-induced bone formation while overcoming BMP9-induced adipogenesis in regenerative medicine.


Assuntos
Adipogenia , Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular , Glicoproteínas/metabolismo , Fator 2 de Diferenciação de Crescimento/metabolismo , Osteogênese , Adipogenia/efeitos dos fármacos , Animais , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Glicoproteínas/antagonistas & inibidores , Glicoproteínas/genética , Fator 2 de Diferenciação de Crescimento/genética , Células HEK293 , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Nus , Osteogênese/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transplante Homólogo
9.
Cell Physiol Biochem ; 41(6): 2383-2398, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28463838

RESUMO

BACKGROUND/AIMS: While recombinant adenoviruses are among the most widely-used gene delivery vectors and usually propagated in HEK-293 cells, generating recombinant adenoviruses remains time-consuming and labor-intense. We sought to develop a rapid adenovirus production and amplification (RAPA) line by assessing human Ad5 genes (E1A, E1B19K/55K, pTP, DBP, and DNA Pol) and OCT1 for their contributions to adenovirus production. METHODS: Stable transgene expression in 293T cells was accomplished by using piggyBac system. Transgene expression was determined by qPCR. Adenoviral production was assessed with titering, fluorescent markers and/or luciferase activity. Osteogenic activity was assessed by measuring alkaline phosphatase activity. RESULTS: Overexpression of both E1A and pTP led to a significant increase in adenovirus amplification, whereas other transgene combinations did not significantly affect adenovirus amplification. When E1A and pTP were stably expressed in 293T cells, the resultant RAPA line showed high efficiency in adenovirus amplification and production. The produced AdBMP9 infected mesenchymal stem cells with highest efficiency and induced most effective osteogenic differentiation. Furthermore, adenovirus production efficiency in RAPA cells was dependent on the amount of transfected DNA. Under optimal transfection conditions high-titer adenoviruses were obtained within 5 days of transfection. CONCLUSION: The RAPA cells are highly efficient for adenovirus production and amplification.


Assuntos
Adenoviridae/fisiologia , Biotecnologia/métodos , Engenharia Genética , Vetores Genéticos/metabolismo , Adenoviridae/genética , Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/metabolismo , Diferenciação Celular , Linhagem Celular , Citometria de Fluxo , Vetores Genéticos/genética , Fator 2 de Diferenciação de Crescimento/genética , Fator 2 de Diferenciação de Crescimento/metabolismo , Células HEK293 , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral
10.
Cell Physiol Biochem ; 41(5): 1905-1923, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28384643

RESUMO

BACKGROUND/AIMS: Mesenchymal stem cells (MSCs) are multipotent progenitors that can differentiate into several lineages including bone. Successful bone formation requires osteogenesis and angiogenesis coupling of MSCs. Here, we investigate if simultaneous activation of BMP9 and Notch signaling yields effective osteogenesis-angiogenesis coupling in MSCs. METHODS: Recently-characterized immortalized mouse adipose-derived progenitors (iMADs) were used as MSC source. Transgenes BMP9, NICD and dnNotch1 were expressed by adenoviral vectors. Gene expression was determined by qPCR and immunohistochem¡stry. Osteogenic activity was assessed by in vitro assays and in vivo ectopic bone formation model. RESULTS: BMP9 upregulated expression of Notch receptors and ligands in iMADs. Constitutively-active form of Notch1 NICD1 enhanced BMP9-induced osteogenic differentiation both in vitro and in vivo, which was effectively inhibited by dominant-negative form of Notch1 dnNotch1. BMP9- and NICD1-transduced MSCs implanted with a biocompatible scaffold yielded highly mature bone with extensive vascularization. NICD1 enhanced BMP9-induced expression of key angiogenic regulators in iMADs and Vegfa in ectopic bone, which was blunted by dnNotch1. CONCLUSION: Notch signaling may play an important role in BMP9-induced osteogenesis and angiogenesis. It's conceivable that simultaneous activation of the BMP9 and Notch pathways should efficiently couple osteogenesis and angiogenesis of MSCs for successful bone tissue engineering.


Assuntos
Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica , Osteogênese , Receptor Notch1/metabolismo , Transdução de Sinais , Animais , Linhagem Celular , Fator 2 de Diferenciação de Crescimento/genética , Células-Tronco Mesenquimais/citologia , Camundongos , Receptor Notch1/genética
11.
Chempluschem ; 89(6): e202400139, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38470161

RESUMO

Constructing heterojunction photocatalysts are widely applied to boost the photocatalytic activity of materials. Here, a novel covalent organic framework (COF) material with heptazine units was developed and hybridized with TiO2 nano particles (NPs) to fabricate the Heptazine-COF@TiO2 photocatalysts for acetaminophen (AAP) photodegradation. The successfully assembled heptazine unit endows the Heptazine-COF with outstanding semiconductor property (optical bandgap is 2.53 eV). The synthesized Heptazine-COF@TiO2 hybrids is proved to have the heterojunction structure with high visible light activity and fast charge-carrier mobility, and exhibits better performance in photodegradation of AAP under visible light. The excellent photodegradation efficiency (rate constant: 0.758 min-1) and high reusability (rate constant: 0.452 min-1 in the 6th cycles) of the optimized sample outperform the traditional inorganic photocatalysts and other heterojunction photocatalysts. In addition, these photocatalysts present universal degradation activity for other dyes and antibiotics.

12.
Int J Biol Macromol ; 267(Pt 1): 131291, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583839

RESUMO

Bacterial cellulose (BC) hydrogels are promising medical biomaterials that have been widely used for tissue repair, wound healing and cartilage engineering. However, the high water content of BC hydrogels increases the difficulty of storage and transportation. Moreover, they will lose their original hydrogel structure after dehydration, which severely limits their practical applications. Introducing the bio-based polyelectrolytes is expected to solve this problem. Here, we modified BC and combined it with quaternized chitosan (QCS) via a chemical reaction to obtain a dehydrated dialdehyde bacterial cellulose/quaternized chitosan (DBC/QCS) hydrogel with repeated swelling behavior and good antibacterial properties. The hydrogel can recover the initial state on the macro scale with a swelling ratio over 1000 % and possesses excellent antimicrobial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with a killing rate of 80.8 % and 81.3 %, respectively. In addition, the hydrogel has excellent biocompatibility, which is conducive to the stretching of L929 cells. After 14 d of in vivo wound modeling in rats, it was found that the hydrogel loaded with pirfenidone (PFD) could promote collagen deposition and accelerate wound healing with scar prevention. This rehydratable hydrogel can be stored and transported under dry conditions, which is promising for practical applications.


Assuntos
Antibacterianos , Celulose , Escherichia coli , Hidrogéis , Staphylococcus aureus , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis/química , Hidrogéis/farmacologia , Ratos , Staphylococcus aureus/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Celulose/análogos & derivados , Escherichia coli/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Camundongos , Linhagem Celular , Masculino , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
13.
ACS Appl Mater Interfaces ; 15(47): 54966-54976, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37967359

RESUMO

Capacitive pressure sensors play an important role in the field of flexible electronics. Despite significant advances in two-dimensional (2D) soft pressure sensors, one-dimensional (1D) fiber electronics are still struggling. Due to differences in structure, the theoretical research of 2D sensors has difficulty guiding the design of 1D sensors. The multiple response factors of 1D sensors and the capacitive response mechanism have not been explored. Fiber sensors urgently need a tailor-made theoretical research and development path. In this regard, we established a fiber pressure-sensing platform using a coaxial wet spinning process. Aiming at the two problems of the soft electrode modulus and dielectric layer thickness, the conclusions are drawn from three aspects: model analysis, experimental verification, and formula derivation. It makes up some theoretical blanks of capacitive fiber pressure sensors. Through the self-regulation of these two factors without a complex structural design, the sensitivity can be significantly improved. This provides a great reference for the design and development of fiber pressure sensors. Besides, taking advantage of the scalability and easy integration of 1D electronics, multipoint sensors prepared by fibers have verified their application potential in health monitoring, human-machine interface, and motion behavior analysis.

14.
Carbohydr Polym ; 321: 121324, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739511

RESUMO

Interface solar water evaporation is a mean of rapidly evaporating water using solar energy. However, it is still a challenge to obtain solar evaporators with simple assembly, durability and high photothermal performance. Here, we demonstrated an effective post foaming strategy for treating nitrogen-doped reduced graphene oxide/bacterial cellulose film (F-NRGO@BC) prepared by a simple in situ culture method. The composite film contains hierarchical porous structure and bubbles on the film, achieving an integrated self-floating interface evaporator with excellent light absorption (96.5 %) and high toughness (200.18 kJ m-3). Porous structure and low enthalpy of F-NRGO@BC make a high evaporation rate of 1.68 kg m-2 h-1 and a low thermal conductivity of 0.644 W m-1 K-1 to ensure effective energy efficiency and heat insulation. This design of controlling surface morphology and internal structure provides a novel way for large-scale preparation and high-performance evaporator.

15.
ACS Nano ; 17(15): 14904-14915, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498777

RESUMO

Soft capacitive pressure sensors with high performance are becoming increasingly in demand in the emerging flexible wearable field. While capacitive fiber pressure sensors have achieved high sensitivity, their sensitivity range is limited to low-pressure levels. As fiber sensors typically require preloading and fixation, this narrow range of high sensitivity poses a challenge for practical applications. To overcome this limitation, the study proposes resistive-capacitive hybrid response fiber pressure sensors (HFPSs) with three-layer core-sheath structures. The trigger and sensitivity enhancement mechanisms of the hybrid response are determined through model analysis and experimental verification. By adjustment of the sensitivity enhancement range of the hybrid response, the sensitivity attenuation of HFPSs is alleviated significantly. The obtained results demonstrate that HFPSs have excellent characteristics such as fast response, low hysteresis, wide response frequency, small signal drift, and good durability. The hybrid response enhances the practical sensitivity of HFPSs for various applications. With enhanced sensitivity, HFPSs can effectively monitor pulse signals at preloads ranging from 0 to 22.7 kPa. This wide range of preloads improves the fault tolerance of pulse monitoring and expands the potential application scenarios of fiber pressure sensors.

16.
Carbohydr Polym ; 308: 120647, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36813339

RESUMO

Skin wounds need an appropriate wound dressing to help prevent bacterial infection and accelerate wound closure. Bacterial cellulose (BC) with a three-dimensional (3D) network structure is an important commercial dressing. However, how to effectively load antibacterial agents and balance the antibacterial activity is a lingering issue. Herein, this study aims to develop a functional BC hydrogel containing silver-loaded zeolitic imidazolate framework-8 (ZIF-8) antibacterial agent. The tensile strength of the prepared biopolymer dressing is >1 MPa, the swelling property is over 3000 %, the temperature can reach 50 °C in 5 min with near-infrared (NIR) and the release of Ag+ and Zn2+ is stable. In vitro investigation shows that the hydrogel displays enhanced antibacterial activity, and the bacteria survival ratios are only 0.85 % and 0.39 % against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In vitro cell experiments present that BC/polydopamine/ZIF-8/Ag (BC/PDA/ZIF-8/Ag) shows satisfactory biocompatibility and promising angiogenic ability. In vivo study, the full-thickness skin defect on rats demonstrates remarkably wound healing ability and accelerated skin re-epithelialization. This work presents a competitive functional dressing with effective antibacterial properties and accelerative angiogenesis activities for wound repair.


Assuntos
Infecções Estafilocócicas , Infecção dos Ferimentos , Ratos , Animais , Celulose/química , Escherichia coli , Hidrogéis/química , Staphylococcus aureus , Cicatrização , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Infecção dos Ferimentos/tratamento farmacológico
17.
J Am Soc Mass Spectrom ; 34(7): 1295-1304, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37338210

RESUMO

Recently, we developed a novel microprobe electrospray ionization (µPESI) source and its coupled MS (µPESI-MS/MS) system. Here, we aimed to widely validate the µPESI-MS/MS method for quantitative analysis of drugs in plasma samples. Furthermore, the relationship between the quantitative performance of the µPESI-MS/MS method and the physicochemical properties of target drugs was analyzed. The µPESI-MS/MS methods for quantitative analysis of 5 representative drugs with a relatively wide range of molecular weight, pKa, and log P values were developed and validated. The results showed that the linearity, accuracy, and precision of these methods met the requirements of the European Medicines Agency (EMA) guidance. Then a total of 75 drugs from plasma samples were primarily detected using the µPESI-MS/MS methods, among which 48 drugs could be quantitatively measured. Logistics regression suggested that drugs with significantly greater log P and physiological charge had better quantitative performance using the µPESI-MS/MS method. Collectively, these results clearly demonstrate the practical application of the µPESI-MS/MS system as a rapid approach to the quantitative analysis of drugs in plasma samples.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Sistemas de Liberação de Medicamentos , Cromatografia Líquida de Alta Pressão/métodos
18.
Inflammation ; 45(3): 1118-1132, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34988755

RESUMO

Nasal polyps (NPs) are multifactorial soft growths inside the nasal passages and are associated with chronic inflammation that originate from the nasal and paranasal sinus mucosae. This study focused on the role of microRNA (miR)-125b and the molecules associated with NP development. Differentially expressed miRNAs between nasal tissues from patients with chronic rhinosinusitis (CRS) with NP (CRSwNP) and CRS without NP (CRSsNP) were screened using microarray analysis. A murine model of CRSwNP was established. The expression of miR-125b in murine tissues was examined using reverse transcription quantitative polymerase chain reaction. Candidate upstream regulators of miR-125b were predicted using bioinformatics tools, and the binding relationship between specificity protein 1 (Sp1) and miR-125b was validated using luciferase and chromatin immunoprecipitation assays. Altered expression of Sp1 and miR-125b was induced to evaluate their relevance to the progression of NPs. miR-125b expression was significantly upregulated in NP tissues from patients with CRSwNP. Sp1 was confirmed as an upstream regulator that promotes miR-125b transcription in NPs. Overexpression of Sp1 reduced levels of d-dimer (an indicator of fibrinogen degradation products) and tissue-type plasminogen activator (t-PA) but increased eosinophil cationic protein and peroxidase levels, as well as the levels of inflammatory factors interleukin-5 (IL-5) and IL-8 in murine NP tissues. However, these trends were reversed after miR-125b downregulation. Sp1 and miR-125b were found to activate the Wnt/ß-catenin signaling pathway in NPs. This study demonstrated that Sp1, an upstream transcription factor of miR-125b, accumulates on the miR-125b promoter to activate its transcription, which induces inflammation and fibrin deposition in NP by activating the Wnt/ß-catenin axis.


Assuntos
MicroRNAs , Pólipos Nasais , Rinite , Sinusite , Fator de Transcrição Sp1 , Via de Sinalização Wnt , Animais , Doença Crônica , Fibrina , Humanos , Inflamação/metabolismo , Camundongos , MicroRNAs/metabolismo , Pólipos Nasais/metabolismo , Pólipos Nasais/patologia , Rinite/metabolismo , Rinite/patologia , Sinusite/metabolismo , Sinusite/patologia , Fator de Transcrição Sp1/metabolismo
19.
Front Vet Sci ; 9: 882971, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35647104

RESUMO

Porcine reproductive and respiratory syndrome (PRRS) is one of the most important swine diseases causing enormous losses to pig producers all over the world. The intervention measure of "load-close-exposure" [interrupting the introduction of replacement pigs combined with whole-herd exposure to live PRRS virus (PRRSV)] has been widely used in North America and has shown wonderful outcomes in controlling PRRS in the field. In the present study, we performed analyses of the production performance of four herds acutely infected with PRRSV by adopting this measure for the first time in China. Our results showed that the development rate of gilts decreased by a mean of 8.56%, the farrowing rate of breeding sows decreased from 86.18 to 77.61%, the number of piglets born alive per sow decreased by a mean of 0.73 pigs, and the pre-weaning and post-weaning mortality of piglets increased by a mean of 2.74-4.97% compared to the parameters of 6 months before an outbreak. The time to PRRSV stability (TTS), defined as the time in weeks it took to produce PRRSV-negative pigs at weaning, is an important indicator of successful control of PRRSV. The median TTS among herds A, C, and D was 21.8 weeks (21.6 22.1 weeks). In herd B, TTS was 42.3 weeks, which could be explained by the double introduction of gilts. Our study suggests that the "load-close-exposure" strategy may be a good alternative for Chinese producers and veterinaries to control PRRS in the field.

20.
ACS Appl Mater Interfaces ; 14(40): 45954-45965, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36181479

RESUMO

Conductive polyzwitterionic hydrogels with good adhesion properties show potential prospect in implantable electrodes and electronic devices. Adhesive property of polyzwitterionic hydrogels in humid environments can be improved by the introduction of catechol groups. However, common catechol modifiers can usually quench free radicals, resulting in a contradiction between long-term tissue adhesion and hydrogel toughness. By adding tannic acid (TA) to the dispersion of clay nanosheets and nanofibers, we designed TA-coated nanoflowers and nanofibers as the reinforcing phase to prepare polyzwitterionic hydrogels with adhesion properties. The hydrogel combines the mussel-like and zwitterionic co-adhesive mechanism to maintain long-term adhesion in underwater environments. In particular, the noncovalent cross-linking provided by the nanoflower structure effectively compensates for the defects caused by free-radical quenching so that the hydrogel obtained a high stretchability of over 2900% and a toughness of 1.16 J/m3. The hydrogel also has excellent anti-biofouling property and shows resistance to bacteria and cells. In addition, the hydrogel possesses a low modulus (<10 kPa) and ionic conductivity (0.25 S/m), making it an ideal material for the preparation of implantable electrodes.


Assuntos
Incrustação Biológica , Hidrogéis , Adesivos/química , Incrustação Biológica/prevenção & controle , Catecóis , Argila , Eletrodos , Hidrogéis/química , Hidrogéis/farmacologia , Polímeros/química , Taninos
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