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1.
Microb Cell Fact ; 21(1): 128, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761329

RESUMO

BACKGROUND: In previous work, we developed an E. coli extracellular secretion platform XTHHly based on the hemolysin A secretion system. It can produce bioactive peptides with simple purification procedures. However, the wider application of this platform is limited by poor secretion efficiency. RESULTS: In this study, we first discovered a positive correlation between the isoelectric point (pI) value of the target protein and the secretion level of the XTHHly system. Given the extremely high secretion level of S tag, we fused it at the N-terminus and created a novel SHTXTHHly system. The SHTXTHHly system significantly increased the secretion levels of antimicrobial peptides (PEW300, LL37, and Aurein 1.2) with full bioactivities, suggesting its excellent capacity for secretory production of bioactive peptides. Furthermore, RGDS, IL-15, and alcohol dehydrogenase were successfully secreted, and their bioactivities were largely maintained in the fusion proteins, indicating the potential applications of the novel system for the rapid determination of protein bioactivities. Finally, using the SHTXTHHly system, we produced the monomeric Fc, which showed a high affinity for Fcγ Receptor I and mediated the antibody-dependent immunological effects of immune cells, demonstrating its potential applications in immunotherapies. CONCLUSIONS: The SHTXTHHly system described here facilitates the secretory production of various types of proteins in E. coli. In comparison to previously reported expression systems, our work enlightens an efficient and cost-effective way to evaluate the bioactivities of target proteins or produce them.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Transporte Biológico , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas Hemolisinas/metabolismo , Peptídeos/metabolismo , Transporte Proteico , Proteínas Recombinantes de Fusão/metabolismo
2.
J Bone Miner Metab ; 40(3): 415-421, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35103839

RESUMO

INTRODUCTION: The progression of osteoarthritis (OA) requires the involvement of lipopolysaccharide (LPS)-induced inflammation, in which circTMOD3 plays an important role. We predicted that circTMOD3 could interact with miR-27a to inhibit LPS-induced chondrocyte apoptosis and explored the interaction between circTMOD3 and miR-27a in OA. MATERIALS AND METHODS: Total RNAs were isolated from cartilage tissue samples from both OA patients (n = 62) and controls (n = 62) and subjected to RT-qPCRs to determine circTMOD3 and miR-27a (mature and premature) expression. Subcellular location of circTMOD3 and its interaction with premature miR-27a were analyzed using subcellular fractionation assay and RNA-RNA pulldown assay, respectively. CircTMOD3 was overexpressed in chondrocytes to study its role in miR-27a maturation. The roles of circTMOD3 and miR-27a in LPS-induced chondrocyte apoptosis were analyzed using cell apoptosis assay. RESULTS: CircTMOD3 and premature miR-27a levels were increased while mature miR-27a level was decreased in OA. CircTMOD3 was located in both nuclear and cytoplasm fractions of chondrocytes. CircTMOD3 directly interacted with premature miR-27a and promoted LPS-induced chondrocyte apoptosis, while miR-27a inhibited LPS-induced chondrocyte apoptosis. Moreover, circTMOD3 overexpression suppressed miR-27a maturation and reduced the inhibitory effects of miR-27a on LPS-induced chondrocyte apoptosis. CONCLUSION: CircTMOD3 suppresses miR-27a maturation in OA to promote chondrocyte apoptosis induced by LPS.


Assuntos
Condrócitos , MicroRNAs , Osteoartrite , RNA Circular , Apoptose/genética , Estudos de Casos e Controles , Condrócitos/metabolismo , Condrócitos/patologia , Humanos , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Osteoartrite/patologia , RNA Circular/genética , RNA Circular/metabolismo
3.
Injury ; 53(4): 1361-1367, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35082056

RESUMO

BACKGROUND: Osteonecrosis of femoral head (ONFH) is a pathological state caused by lack of blood supply in femoral head. This study aimed to explore the function of Lycium barbarum polysaccharide (LBP), an antioxidant agent extracted from L. barbarum, on ONFH. METHODS: Osteonecrosis rat model was generated using lipopolysaccharide (LPS) and methylprednisolone followed by examination of body weight, blood glucose, morphology, and BMSC osteoblast differentiation. The effect and underlying mechanism of LBP on the proliferation, apoptosis, and osteoblast differentiation of BMSC were determined with or without LPS or hypoxia treatment using CCK-8. Alizarin Red S staining, flow cytometry, and western blot, respectively. RESULT: LBP could protect against glucocorticoid-induced ONFH in rats, resulting in improved sparse trabecular bone, empty lacunae and bone cell coagulation. Moreover, LBP promoted the proliferation and osteoblast differentiation of bone mesenchymal-derived stem cells (BMSCs) in a dose-dependent manner. Furthermore, LBP enhanced osteoblast differentiation of BMSCs under hypoxia condition. Mechanistically, we found that LBP treatment enhanced Runx2 and ALP expression in BMSCs. LBP restored the expression of Runx2 and ALP under hypoxia, suggesting that LBP might be involved in regulating Runx2/ALP expression and contributed to osteoblast differentiation. Knockdown of Runx2 significantly inhibited BMSCs proliferation, while LBP treatment did not rescue the osteoblast differentiation ability of BMSCs with Runx2 knockdown. CONCLUSION: Our findings suggested that LBP protects against ONFH via regulating Runx2 expression, which could be utilized to treat patients suffering ONFH.


Assuntos
Medicamentos de Ervas Chinesas , Necrose da Cabeça do Fêmur , Animais , Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core , Medicamentos de Ervas Chinesas/efeitos adversos , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/prevenção & controle , Humanos , Osteogênese , Ratos
4.
Viruses ; 13(12)2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34960821

RESUMO

African swine fever (ASF) is a devastating disease in domestic and wild pigs. Since the first outbreak of ASF in August 2018 in China, the disease has spread throughout the country with an unprecedented speed, causing heavy losses to the pig and related industries. As a result, strategies for managing the disease are urgently needed. This paper summarizes the important aspects of three key elements about African swine fever virus (ASFV) transmission, including the sources of infection, transmission routes, and susceptible animals. It overviews the relevant prevention and control strategies, focusing on the research progress of ASFV vaccines, anti-ASFV drugs, ASFV-resistant pigs, efficient disinfection, and pig farm biosecurity. We then reviewed the key technical points concerning pig farm repopulation, which is critical to the pork industry. We hope to not only provide a theoretical basis but also practical strategies for effective dealing with the ASF epidemic and restoration of pig production.


Assuntos
Febre Suína Africana/prevenção & controle , Febre Suína Africana/transmissão , Animais , Antivirais/uso terapêutico , Suscetibilidade a Doenças , Desinfecção , Fazendas , Transmissão Vertical de Doenças Infecciosas , Suínos , Vacinas Virais/imunologia
5.
Virol Sin ; 36(6): 1626-1643, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34704222

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) continues to cause significant economic loss worldwide and remains a serious threat to the pork industry. Currently, vaccination strategies provide limited protection against PRRSV infection, and consequently, new antiviral strategies are urgently required. Andrographolide (Andro) and its derivative potassium dehydrographolide succinate (PDS) have been used clinically in China and other Asian countries as therapies for inflammation-related diseases, including bacterial and viral infections, for decades. Here, we demonstrate that Andro and PDS exhibit robust activity against PRRSV replication in Marc-145 cells and primary porcine alveolar macrophages (PAMs). The two compounds exhibited broad-spectrum inhibitory activities in vitro against clinically circulating type 2 PRRSV GD-HD, XH-GD, and NADC30-like HNhx strains in China. The EC50 values of Andro against three tested PRRSV strain infections in Marc-145 cells ranged from 11.7 to 15.3 µmol/L, with selectivity indexes ranging from 8.3 to 10.8, while the EC50 values of PDS ranged from 57.1 to 85.4 µmol/L, with selectivity indexes ranging from 344 to 515. Mechanistically, the anti-PRRSV activity of the two compounds is closely associated with their potent suppression on NF-κB activation and enhanced oxidative stress induced by PRRSV infection. Further mechanistic investigations revealed that PDS, but not Andro, is able to directly interact with PRRSV particles. Taken together, our findings suggest that Andro and PDS are promising PRRSV inhibitors in vitro and deserves further in vivo studies in swine.


Assuntos
Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Diterpenos , Potássio , Ácido Succínico , Suínos , Replicação Viral
6.
J Sci Comput ; 88(3)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34483475

RESUMO

Associated to a finite measure on the real line with finite moments are recurrence coefficients in a three-term formula for orthogonal polynomials with respect to this measure. These recurrence coefficients are frequently inputs to modern computational tools that facilitate evaluation and manipulation of polynomials with respect to the measure, and such tasks are foundational in numerical approximation and quadrature. Although the recurrence coefficients for classical measures are known explicitly, those for nonclassical measures must typically be numerically computed. We survey and review existing approaches for computing these recurrence coefficients for univariate orthogonal polynomial families and propose a novel "predictor-corrector" algorithm for a general class of continuous measures. We combine the predictor-corrector scheme with a stabilized Lanczos procedure for a new hybrid algorithm that computes recurrence coefficients for a fairly wide class of measures that can have both continuous and discrete parts. We evaluate the new algorithms against existing methods in terms of accuracy and efficiency.

7.
ACS Appl Mater Interfaces ; 12(26): 29218-29227, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32490658

RESUMO

Performance degradation of lithium/sodium-ion capacitors (LICs/SICs) mainly originates from anode pulverization, particularly the alloying and conversion types, and has spurred research for alternatives with an insertion mechanism. Three-dimensional (3D) topotactic host materials remain much unexplored compared to two-dimensional (2D) ones (graphite, etc.). Herein, vanadium monophosphide (VP) is designed as a 3D topotactic host anode. Ex situ electrochemical characterizations reveal that there are no phase changes during (de)intercalation, which follows the topotactic intercalation mechanism. Computational simulations also confirm the metallic feature and topotactic structure of VP with a spacious interstitial position for the accommodation of guest species. To boost the electrochemical performance, carbon nano-onions (CNOs) are coupled with 3D VP. Superior specific capacity and rate capability of VP-CNOs vs lithium/sodium can be delivered due to the fast ion diffusion nature. An exceptional capacity retention of above 86% is maintained after 20 000 cycles, benefitting from the topotactic intercalation process. The optimized LICs/SICs exhibit high energy/power densities and an ultrastable lifespan of 20 000 cycles, which outperform most of the state-of-the-art LICs and SICs, demonstrating the potential of VP-CNOs as insertion anodes. This exploration would draw attention with regard to insertion anodes with 3D topotactic host topology and provide new insights into anode selection for LICs/SICs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-24845440

RESUMO

The complete sequence of the mitochondrial genome of the mandarin vole (Lasiopodomys mandarinus) was completed and annotated in this study. The circular genome is 16,375 bp in length and contains the typical 37 genes that are arranged in the same order as that of the putative ancestor of vertebrate, 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 2 non-coding regions. This study will provide genetic resource to clarify the taxonomic position of genus Lasiopodomys.


Assuntos
Arvicolinae/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Animais , Pareamento de Bases/genética , RNA de Transferência/genética
9.
Mitochondrial DNA ; 26(5): 759-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24397765

RESUMO

The complete mitochondrial genome of black giant squirrel (Ratufa bicolor) from Hainan Island was sequenced and characterized in detail. The 16,563 bp genome was composed of 13 protein-coding genes, 22 tRNAs, 2 rRNAs and 2 non-coding regions. The mitochondrial genome of R. bicolor presented in this report will be useful for species identification, conversation and clarifying the controversial taxonomic status of genus Ratufa.


Assuntos
Genoma Mitocondrial , Genômica , Sciuridae/genética , Animais , Códon , Genes Mitocondriais , Genômica/métodos , Fases de Leitura Aberta , Análise de Sequência de DNA
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