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1.
Environ Sci Technol ; 58(24): 10515-10523, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38622088

RESUMO

Hydrogen sulfide (H2S), a toxic gas abundant in natural gas fields and refineries, is currently being removed mainly via the Claus process. However, the emission of sulfur-containing pollutants is hard to be prevented and the hydrogen element is combined to water. Herein, we report an electron-mediated off-field electrocatalysis approach (OFEC) for complete splitting of H2S into H2 and S under ambient conditions. Fe(III)/Fe(II) and V(II)/V(III) redox mediators are used to fulfill the cycles for H2S oxidation and H2 production, respectively. Fe(III) effectively removes H2S with almost 100% conversion during its oxidation process. The H+ ions are reduced by V(II) on a nonprecious metal catalyst, tungsten carbide. The mediators are regenerated in an electrolyzer at a cell voltage of 1.05 V, close to the theoretical potential difference (1.02 V) between Fe(III)/Fe(II) and V(II)/V(III). In a laboratory bench-scale plant, the energy consumption for the production of H2 from H2S is estimated to be 2.8 kWh Nm-3 H2 using Fe(III)/Fe(II) and V(II)/V(III) mediators and further reduced to about 0.5 kWh Nm-3 H2 when employing well-designed heteropolyacid/quinone mediators. OFEC presents a cost-effective approach for the simultaneous production of H2 and elemental sulfur from H2S, along with the complete removal of H2S from industrial processes. It also provides a practical platform for electrochemical reactions involving solid precipitation and organic synthesis.


Assuntos
Sulfeto de Hidrogênio , Hidrogênio , Enxofre , Sulfeto de Hidrogênio/química , Hidrogênio/química , Catálise , Enxofre/química , Oxirredução , Eletroquímica , Técnicas Eletroquímicas
2.
BMC Genomics ; 24(1): 46, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707768

RESUMO

Terpenoids are important compounds associated with the pest and herbivore resistance mechanisms of plants; consequently, it is essential to identify and explore terpene synthase (TPS) genes in maize. In the present study, we identified 31 TPS genes based on a pan-genome of 26 high-quality maize genomes containing 20 core genes (present in all 26 lines), seven dispensable genes (present in 2 to 23 lines), three near-core genes (present in 24 to 25 lines), and one private gene (present in only 1 line). Evaluation of ka/ks values of TPS in 26 varieties revealed that TPS25 was subjected to positive selection in some varieties. Six ZmTPS had ka/ks values less than 1, indicating that they were subjected to purifying selection. In 26 genomes, significant differences were observed in ZmTPS25 expression between genes affected by structural variation (SV) and those not affected by SV. In some varieties, SV altered the conserved structural domains resulting in a considerable number of atypical genes. The analysis of RNA-seq data of maize Ostrinia furnacalis feeding revealed 10 differentially expressed ZmTPS, 9 of which were core genes. However, many atypical genes for these responsive genes were identified in several genomes. These findings provide a novel resource for functional studies of ZmTPS.


Assuntos
Alquil e Aril Transferases , Zea mays , Zea mays/genética , Zea mays/metabolismo , Terpenos/metabolismo , Alquil e Aril Transferases/genética , Plantas/metabolismo
3.
BMC Genomics ; 24(1): 332, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322453

RESUMO

The rich genetic diversity in Citrullus lanatus and the other six species in the Citrullus genus provides important sources in watermelon breeding. Here, we present the Citrullus genus pan-genome based on the 400 Citrullus genus resequencing data, showing that 477 Mb contigs and 6249 protein-coding genes were absent in the Citrullus lanatus reference genome. In the Citrullus genus pan-genome, there are a total of 8795 (30.5%) genes that exhibit presence/absence variations (PAVs). Presence/absence variation (PAV) analysis showed that a lot of gene PAV were selected during the domestication and improvement, such as 53 favorable genes and 40 unfavorable genes were identified during the C. mucosospermus to C. lanatus landrace domestication. We also identified 661 resistance gene analogs (RGAs) in the Citrullus genus pan-genome, which contains 90 RGAs (89 variable and 1 core gene) located on the pangenome additional contigs. By gene PAV-based GWAS, 8 gene presence/absence variations were found associated with flesh color. Finally, based on the results of gene PAV selection analysis between watermelon populations with different fruit colors, we identified four non-reference candidate genes associated with carotenoid accumulation, which had a significantly higher frequency in the white flesh. These results will provide an important source for watermelon breeding.


Assuntos
Citrullus , Citrullus/genética , Domesticação , Melhoramento Vegetal , Genoma de Planta , Análise de Sequência de DNA
4.
PLoS Genet ; 16(11): e1009159, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175846

RESUMO

Tumor metastasis is the major cause of poor prognosis and mortality in colorectal cancer (CRC). However, early diagnosis of highly metastatic CRC is currently difficult. In the present study, we screened for a novel biomarker, GDNF family receptor alpha 1 (GFRA1) based on the expression and methylation data in CRC patients from The Cancer Genome Altlas (TCGA), followed by further analysis of the correlation between the GFRA1 expression, methylation, and prognosis of patients. Our results show DNA hypomethylation-mediated upregulation of GFRA1 in invasive CRC, and it was found to be correlated with poor prognosis of CRC patients. Furthermore, GFRA1 methylation-modified sequences were found to have potential as methylation diagnostic markers of highly metastatic CRC. The targeted demethylation of GFRA1 by dCas9-TET1CD and gRNA promoted CRC metastasis in vivo and in vitro. Mechanistically, demethylation of GFRA1 induces epithelial-mesenchymal transition (EMT) by promoting AKT phosphorylation and increasing c-Jun expression in CRC cells. Collectively, our findings indicate that GFRA1 hypomethylation can promote CRC invasion via inducing EMT, and thus, GFRA1 methylation can be used as a biomarker for the early diagnosis of highly metastasis CRC.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Transição Epitelial-Mesenquimal/genética , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Neoplasias Pulmonares/genética , Animais , Proliferação de Células/genética , Estudos de Coortes , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Biologia Computacional , Desmetilação do DNA , Metilação de DNA , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Humanos , Neoplasias Pulmonares/secundário , Camundongos , Invasividade Neoplásica/genética , Fosforilação/genética , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA-Seq , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Insect Sci ; 23(4)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37471132

RESUMO

The response of Spodoptera frugiperda genes toward insecticides is crucial for guiding insecticide use. The regulation of the S. frugiperda genes via long noncoding RNAs (lncRNAs) under insecticide treatment should be investigated. In this study, 452 differentially expressed lncRNAs were identified by analyzing RNA-sequencing data of S. frugiperda under 23 pesticide treatments. We found 59 and 43 differentially expressed lncRNAs that could regulate detoxification-related cytochrome P450 and UDP-glucuronosyltransferase genes, respectively. Furthermore, the target genes of differentially expressed lncRNAs were enriched in Pfam, including chitin bind 4 and gene ontology terms such as structural constituent of the cuticle, revealing their potential mechanism of action on the growth inhibition of S. frugiperda larvae. Insecticide-specific expression of lncRNAs highlights the properties and commonalities of different insecticide-induced lncRNA regulatory mechanisms. To conclude, the results of this study provide new insights and perspectives on the use of 23 insecticides via lncRNA regulation of mRNAs.


Assuntos
Inseticidas , Mariposas , Praguicidas , RNA Longo não Codificante , Animais , Inseticidas/farmacologia , Spodoptera , Larva , RNA Longo não Codificante/genética , Mariposas/genética
6.
Mol Ther ; 27(1): 244-260, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30527756

RESUMO

Immunotherapy based on the immune checkpoint blockade has emerged as the most promising approach for cancer therapy. However, the proportion of colorectal cancer patients who benefit from immunotherapy is small due to the immunosuppressive tumor microenvironment. Hence, combination immunotherapy is an ideal strategy to overcome this limitation. In this study, we developed a novel combination of CSF-1R (colony-stimulating factor 1 receptor) inhibitor (PLX3397), oncolytic viruses, and anti-PD-1 antibody. Our results demonstrated that the triple treatment synergistically conferred significant tumor control and prolonged the survival of mouse models of colon cancer. Approximately 43% and 82% of mice bearing the CT26 and MC38 tumor, respectively, survived long term following the triple treatment. This combination therapy reprogrammed the immunosuppressive tumor microenvironment toward a CD8+ T cell-biased anti-tumor immunity by increasing T cell infiltration in the tumor and augmenting anti-tumor CD8+ T cell function. Our results provide a robust strategy for clinical combination therapy.


Assuntos
Vírus Oncolíticos/fisiologia , Receptor de Morte Celular Programada 1/imunologia , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Aminopiridinas/farmacologia , Animais , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Neoplasias do Colo/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Vírus Oncolíticos/genética , Pirróis/farmacologia , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
8.
J Cell Mol Med ; 22(12): 6190-6201, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30255547

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common and deadly malignant tumors in the world, especially in China. Follistatin-like protein 5 (FSTL5) is a member of the FSTL family, which is involved in cell proliferation, migration, differentiation, and embryo development. We aimed to investigate the function and underlying mechanism of FSTL5 in HCC. FSTL5 expression was determined by immunohistochemistry staining in a liver cancer tissue microarray (TMA) and the correlation between FSTL5 and the prognosis of HCC patients was analysed. Further proliferation assay, colony formation assay, flow cytometry, and xenograft tumor model were performed to investigate the bioeffects of FSTL5 in HCC in vitro and in vivo. We found that FSTL5 expression was downregulated in HCC tissues and positively correlated with the prognosis of patients with HCC at tumor node metastasis stage I/II. Overexpression of FSTL5 efficiently impaired HCC growth both in vivo and in vitro with an exogenous manner. Mechanistic investigation demonstrated that FSTL5 promoted HCC cell apoptosis in a caspase-dependent manner and regulated Bcl-2 family proteins. These results indicate that FSTL5 may be a potential novel target for HCC treatment, and a biomarker for tumor prognosis.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas Relacionadas à Folistatina/genética , Neoplasias Hepáticas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Idoso , Animais , Apoptose/genética , Carcinoma Hepatocelular/patologia , Caspases/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Prognóstico
9.
J Cell Mol Med ; 21(8): 1532-1544, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28211159

RESUMO

Lung cancer is globally widespread and associated with high morbidity and mortality. DDA1 (DET1 and DDB1 associated 1) was first discovered and registered in the GenBank database by our colleagues. DDA1, an evolutionarily conserved gene, might have significant functions. Recent reports have demonstrated that DDA1 is linked to the ubiquitin-proteasome pathway and facilitates the degradation of target proteins. However, the function of DDA1 in lung cancer was previously unknown. This study aimed to investigate whether DDA1 contributes to tumorigenesis and progression of lung cancer. We found that the expression of DDA1 in normal lung cells and tissue was significantly lower than that in lung cancer and was associated with poor prognosis. DDA1 overexpression promoted proliferation of lung tumour cells and facilitated cell cycle progression in vitro and subcutaneous xenograft tumour progression in vivo. Mechanistically, this was associated with the regulation of S phase and cyclins including cyclin D1/D3/E1. These results indicate that DDA1 promotes lung cancer progression, potentially through promoting cyclins and cell cycle progression. Therefore, DDA1 may be a potential novel target for lung cancer treatment, and a biomarker for tumour prognosis.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Fase S/genética , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma de Pulmão , Idoso , Animais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclina D3/genética , Ciclina D3/metabolismo , Ciclina E/genética , Ciclina E/metabolismo , Proteínas de Ligação a DNA/metabolismo , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Transplante de Neoplasias , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Prognóstico , Transdução de Sinais , Análise de Sobrevida , Análise Serial de Tecidos
10.
Acta Vet Hung ; 65(3): 402-416, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28956480

RESUMO

The NOD-like receptor protein 3 (NLRP3) inflammasome comprised of NLRP3, ASC and caspase-1 plays an important role in the inflammatory and innate immune response. However, little is known about the expression pattern and histological distribution of these genes in goat. Here, we first cloned the fulllength cDNAs of the NLRP3, ASC and caspase-1 genes of Hainan black goat and produced their polyclonal antibodies. Tissue-specific expression and histological distribution of these genes were analysed. Phylogenetic analysis revealed that these three goat genes had high homology with Bos taurus genes and low homology with avian or fish genes. After immunisations with these recombinant Histagged proteins, the titres of antiserum were higher than 1:1024 and purified IgG was obtained. These three genes were expressed in all examined tissues, the mRNA expression level of NLRP3 and caspase-1 was most abundant in the spleen and mesenteric lymph nodes (MLNs), while ASC was primary expressed in the liver, spleen and kidney. The histological distribution of NLRP3, ASC and caspase-1 was detected in myocardial cells, hepatocytes, focal lymphocytes, bronchiolar epithelial cells, renal tubular epithelial cells, cortical neurons and endothelial cells of the germinal centres in the MLNs. These results will be helpful in further investigations into the function of the NLRP3 inflammasome and in elucidating its role in caprine inflammatory diseases.


Assuntos
Cabras/metabolismo , Inflamassomos/metabolismo , Inflamação/veterinária , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transcriptoma , Animais , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/genética , Caspase 1/metabolismo , Regulação da Expressão Gênica , Cabras/genética , Imunoglobulina G , Inflamação/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Tecidual
11.
Med Microbiol Immunol ; 205(5): 501-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27401907

RESUMO

H7N9 influenza A virus (IAV)-infected human cases are increasing and reported over 200 mortalities since its first emergence in 2013. Host inflammatory response contributes to the clearance of influenza virus; meanwhile, the induced "cytokine storm" also leads to pathological lesions. However, what inflammation-related response of the host for H7N9 influenza A virus infection to survival from injures of exuberant cytokine release is still obscure. In this research, expression pattern and histological distribution of inflammation-related genes, RIP3, NLRP3, IL-1ß, TNF-α, Slit2 and Robo4 in the lung of BALB/c mice infected with two H7N9 IAV strains with only a PB2 residue 627 difference were investigated, as well as the histopathological injury of the lung. Results showed that significantly higher expression level of NLRP3, RIP3, IL-1ß and TNF-α in H7N9-infected groups compared with the control would play a key role in driving lung pathological lesion. While the expression level of Slit2 and Robo4 in H7N9 rVK627E group had significantly increased trend than VK627 which might be the main factor to inhibit the interstitial pneumonia and infiltration. Also, H7N9 induced the histopathological changes in the lung of infected mice, and RIP3, NLRP3, IL-1ß, TNF-α, Slit2 and Robo4 showed cell-specific distribution in the lung. The results will provide basic data for further research on the mechanism of inflammatory response and understanding of the role of site 627 in PB2 in H7N9 IAVs infection. In addition, enhancing the resilience of the host vascular system to the inflammatory response by regulation of Slit2-Robo4 signaling pathway might provide a novel strategy for H7N9 IAVs infection.


Assuntos
Perfilação da Expressão Gênica , Inflamação/patologia , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Pulmão/patologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Animais , Feminino , Histocitoquímica , Imuno-Histoquímica , Camundongos Endogâmicos BALB C
12.
Biochem Genet ; 54(4): 360-367, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26969469

RESUMO

RIP3, a member of receptor-interacting protein family, is serine/threonine kinase that contributes to necrosis and promotes systematic inflammation. However, detailed information of the expression pattern and tissue distribution in BALB/c mice, a commonly used laboratory animal model, is still unavailable. Here, we provided the basic data of expression profile and histologic distribution of RIP3 in tissues of BALB/c mice. Rip3 mRNA expression levels and tissue distribution were detected by real-time quantitative PCR and immunohistochemical detection, respectively. Rip3 mRNA expression showed the highest level in the spleen and duodenum, while with the lowest level in brain. Immunohistochemical detection revealed this protein located in different type cells in different tissues. What's more, the obvious positive staining in nuclear was detected in liver cells and neurons in cerebral cortex of the brain, while cells in other organs, including heart, spleen, lung, kidney, stomach, duodenum and trachea, showed strong positive mainly in cytoplasm. The results will help us to further understand the site-specific functions of RIP3 in necrosis and inflammatory responses.


Assuntos
Encéfalo/metabolismo , Duodeno/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Baço/metabolismo , Animais , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Tecidual , Transcriptoma
13.
Angew Chem Int Ed Engl ; 54(47): 13994-8, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26332348

RESUMO

In heterogeneous catalysis, supports play a crucial role in modulating the geometric and electronic structure of the active metal phase for optimizing the catalytic performance. A γ-Al2O3 nanosheet that contains 27% pentacoordinate Al(3+) sites can nicely disperse and stabilize raft-like Pt-Sn clusters as a result of strong interactions between metal and support. Consequently, there are strong electronic interactions between the Pt and Sn atoms, resulting in an increase in the electron density of the Pt sites. When used in the propane dehydrogenation reaction, this catalyst displayed an excellent specific activity for propylene formation with >99% selectivity, and superior anti-coking and anti-sintering properties. Its exceptional ability to maintain the high activity and stability at ultrahigh space velocities further showed that the sheet construction of the catalyst facilitated the kinetic transfer process.

14.
Water Res ; 257: 121674, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38678835

RESUMO

The occurrence of seasonal algae blooms represents a huge dilemma for water resource management and has garnered widespread attention. Therefore, finding methods to control algae pollution and improve water quality is urgently needed. Moderate oxidation has emerged as a feasible way of algae-laden water treatment and is an economical and prospective strategy for controlling algae and endogenous and exogenous pollutants. Despite this, a comprehensive understanding of algae-laden water treatment by moderate oxidation, particularly principles and summary of advanced strategies, as well as challenges in moderate oxidation application, is still lacking. This review outlines the properties and characterization of algae-laden water, which serve as a prerequisite for assessing the treatment efficiency of moderate oxidation. Biomass, cell viability, and organic matter are key components to assessing moderate oxidation performance. More importantly, the recent advancements in employing moderate oxidation as a treatment or pretreatment procedure were examined, and the suitability of different techniques was evaluated. Generally, moderate oxidation is more promising for improving the solid-liquid separation process by the reduction of cell surface charge (stability) and removal/degradation of the soluble algae secretions. Furthermore, this review presents an outlook on future research directions aimed at overcoming the challenges encountered by existing moderate oxidation technologies. This comprehensive examination aims to provide new and valuable insights into the moderate oxidation process.


Assuntos
Oxirredução , Purificação da Água , Purificação da Água/métodos , Biomassa , Eutrofização , Água/química
15.
Toxics ; 11(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36851041

RESUMO

There is limited evidence concerning the association between air pollution and different outpatient visits in moderately polluted areas. This paper investigates the effects of moderate-level air pollution on outpatient visits associated with six categories of clinic department. We analyzed a total of 1,340,791 outpatient visits for the pediatric, respiratory, ear-nose-throat (ENT), cardiovascular, ophthalmology, and orthopedics departments from January 2016 to December 2018. A distributed lag nonlinear model was used to analyze the associations and was fitted and stratified by age and season (central heating season and nonheating season). We found SO2 had the largest effect on pediatrics visits (RR = 1.105 (95%CI: 1.090, 1.121)). Meanwhile, PM2.5 and SO2 had greater effects on ENT visits for people under 50 years old. The results showed a strong association between O3 and cardiovascular outpatient visits in the nonheating season (RR = 1.273, 95% CI: 1.189,1.358). The results showed every 10 µg/m3 increase in SO2 was associated with a lower number of respiratory outpatient visits. Significant different associations were observed in PM2.5, NO2, CO, and O3 on ophthalmology visits between the heating and nonheating seasons. Although no significant association has been found in existing studies, our findings showed PM2.5 and NO2 were significantly related to orthopedic outpatient visits for people under 60 (RR = 1.063 (95%CI: 1.032, 1.095), RR = 1.055 (95%CI: 1.011, 1.101)). This study also found that the effect-level concentrations of air pollutants for some clinic departments were lower than the national standards, which means that people should also pay more attention when the air quality is normal.

16.
Curr Med Chem ; 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927424

RESUMO

BACKGROUND: Natural polymers are organic compounds produced by living organisms. In nature, they exist in three main forms, including proteins, polysaccharides and nucleic acids. In recent years, with the continuous research on drug and gene delivery systems, scholars have found that natural polymers have promising applications in drug and gene delivery systems due to their excellent properties such as biocompatibility, biodegradability, low immunogenicity and easy modification. However, since the structure, physicochemical properties, pharmacological properties and biological characteristics of biopolymer molecules have not yet been entirely understood, further studies are required before large-scale clinical application. METHODS: This review focuses on recent advances in the representative natural polymers such as proteins (albumin, collagen, elastin), polysaccharides (chitosan, alginate, cellulose) and nucleic acids. RESULTS: We introduce the characteristics of various types of natural polymers, and further outline the characterization methods and delivery forms of these natural polymers. CONCLUSION: Finally, we discuss possible challenges for natural polymers in subsequent experimental studies and clinical applications. It provides an important strategy for the clinical application of natural polymers in drug and gene delivery systems.

17.
Hum Gene Ther ; 34(13-14): 616-628, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37227014

RESUMO

Adeno-associated virus (AAV)-based gene therapy has been shown to be safe and effective in numerous animal models and clinical trials for various ophthalmic diseases. Stargardt disease (STGD1; MIM #248200) is the most common autosomal recessive macular dystrophy disease, and the most common form is caused by mutations in the ABCA4 gene, a gene with 6.8 kb coding sequence. Split intein approaches increase the capacity of dual AAV gene therapy, but at the cost of reduced protein expression, which may be insufficient to achieve a therapeutic effect. In this study, we designed various dual split intein ABCA4 vectors and showed that the efficiency of expression of full-length ABCA4 protein is dependent on combinations of types and split sites of the intein system. The most efficient vectors were identified through in vitro screening, and a novel dual AAV8-ABCA4 vector was constructed and subsequently proven to express full-length ABCA4 protein at a high level, reducing bisretinoid formation and correcting the visual function of ABCA4-knockout mice. Furthermore, we evaluated therapeutic effects of different dosages by subretinal injection in mice model. Both therapeutic effects and safety were guaranteed under the treatment of 1.00 × 109 GC/eye. These results support the optimized dual AAV8-ABCA4 approach in future clinical translation for treatment of Stargardt disease.


Assuntos
Degeneração Macular , Doenças Retinianas , Camundongos , Animais , Doença de Stargardt/genética , Doença de Stargardt/terapia , Degeneração Macular/genética , Degeneração Macular/terapia , Terapia Genética/métodos , Camundongos Knockout , Mutação , Doenças Retinianas/terapia
18.
Exp Mol Pathol ; 93(2): 207-12, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22609310

RESUMO

Granulomas, the pathologic hallmarks of tuberculosis, are composed of tightly numerous immune cells that respond to a variety of persistent stimuli during pathogen-host interaction. The granuloma is essential for host containment of mycobacterial infection, however, the mechanism of host and pathogen determinants to recruit immune cells at the site of inflammation and the formation of granulomas remains elusive until now. Macrophage migration inhibitory factor (MIF), a cytokine produced by many cell types, modulates cellular and humoral immune responses and promote lymphocytes migration to the site of infection. In this study, we evaluate the expression of MIF in tuberculous granulomas by three different models of diseases: mouse, human tissues and zebrafish. The overall results demonstrated that the expression of MIF positive signals markedly increased in the tissues which have been infected with mycobacterium, whereas a few presence of MIF in the PBS-treated animals (means the control group). In the mycobacterial-infected animals, the MIF positives distributed extensively within the granuloma especially in the multinucleated giant cells. Thus, three independent lines of evidence support the hypothesis that MIF may be an important player in aggregate immune cells to the granuloma microenvironments in these animal models of tuberculosis.


Assuntos
Modelos Animais de Doenças , Granuloma/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Infecções por Mycobacterium não Tuberculosas/metabolismo , Tuberculose/metabolismo , Animais , Granuloma/microbiologia , Granuloma/patologia , Humanos , Pulmão/metabolismo , Pulmão/microbiologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções por Mycobacterium não Tuberculosas/patologia , Mycobacterium marinum/fisiologia , Mycobacterium tuberculosis/fisiologia , Tuberculose/microbiologia , Tuberculose/patologia , Peixe-Zebra
19.
JMIR Public Health Surveill ; 8(6): e35266, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35507921

RESUMO

BACKGROUND: The SARS-COV-2 virus and its variants pose extraordinary challenges for public health worldwide. Timely and accurate forecasting of the COVID-19 epidemic is key to sustaining interventions and policies and efficient resource allocation. Internet-based data sources have shown great potential to supplement traditional infectious disease surveillance, and the combination of different Internet-based data sources has shown greater power to enhance epidemic forecasting accuracy than using a single Internet-based data source. However, existing methods incorporating multiple Internet-based data sources only used real-time data from these sources as exogenous inputs but did not take all the historical data into account. Moreover, the predictive power of different Internet-based data sources in providing early warning for COVID-19 outbreaks has not been fully explored. OBJECTIVE: The main aim of our study is to explore whether combining real-time and historical data from multiple Internet-based sources could improve the COVID-19 forecasting accuracy over the existing baseline models. A secondary aim is to explore the COVID-19 forecasting timeliness based on different Internet-based data sources. METHODS: We first used core terms and symptom-related keyword-based methods to extract COVID-19-related Internet-based data from December 21, 2019, to February 29, 2020. The Internet-based data we explored included 90,493,912 online news articles, 37,401,900 microblogs, and all the Baidu search query data during that period. We then proposed an autoregressive model with exogenous inputs, incorporating real-time and historical data from multiple Internet-based sources. Our proposed model was compared with baseline models, and all the models were tested during the first wave of COVID-19 epidemics in Hubei province and the rest of mainland China separately. We also used lagged Pearson correlations for COVID-19 forecasting timeliness analysis. RESULTS: Our proposed model achieved the highest accuracy in all 5 accuracy measures, compared with all the baseline models of both Hubei province and the rest of mainland China. In mainland China, except for Hubei, the COVID-19 epidemic forecasting accuracy differences between our proposed model (model i) and all the other baseline models were statistically significant (model 1, t198=-8.722, P<.001; model 2, t198=-5.000, P<.001, model 3, t198=-1.882, P=.06; model 4, t198=-4.644, P<.001; model 5, t198=-4.488, P<.001). In Hubei province, our proposed model's forecasting accuracy improved significantly compared with the baseline model using historical new confirmed COVID-19 case counts only (model 1, t198=-1.732, P=.09). Our results also showed that Internet-based sources could provide a 2- to 6-day earlier warning for COVID-19 outbreaks. CONCLUSIONS: Our approach incorporating real-time and historical data from multiple Internet-based sources could improve forecasting accuracy for epidemics of COVID-19 and its variants, which may help improve public health agencies' interventions and resource allocation in mitigating and controlling new waves of COVID-19 or other relevant epidemics.


Assuntos
COVID-19 , Epidemias , Mídias Sociais , COVID-19/epidemiologia , Surtos de Doenças , Humanos , SARS-CoV-2
20.
Exploration (Beijing) ; 2(2): 20210081, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37323878

RESUMO

Emerging clustered regularly interspaced short palindromic repeat/associated protein (CRISPR/Cas) genome editing technology shows great potential in gene therapy. However, proteins and nucleic acids suffer from enzymatic degradation in the physiological environment and low permeability into cells. Exploiting carriers to protect the CRISPR system from degradation, enhance its targeting of specific tissues and cells, and reduce its immunogenicity is essential to stimulate its clinical applications. Here, the authors review the state-of-the-art CRISPR delivery systems and their applications, and describe strategies to improve the safety and efficacy of CRISPR mediated genome editing, categorized by three types of cargo formats, that is, Cas: single-guide RNA ribonucleoprotein, Cas mRNA and single-guide RNA, and Cas plasmid expressing CRISPR/Cas systems. The authors hope this review will help develop safe and efficient nanomaterial-based carriers for CRISPR tools.

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