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1.
Fish Shellfish Immunol ; 154: 109912, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299405

RESUMO

This study aimed to select high-quality promoters to construct trans-vp28 gene Anabaena sp. PCC7120 and feed Litopenaeus vannamei to assess the effect of L.vannamei against white spot syndrome virus (WSSV). Transgenic algae were created using five plasmids containing PrbcL, Pcpc560, Ptrc, Ptac, and PpsbA. According to the gene expression efficiency and the growth index of transgenic algae, Pcpc560 was determined to be the most efficient promoter. Shrimps were continuously fed trans-vp28 gene Anabaena sp. PCC7120 for one week and then challenged with WSSV. After the challenge, the transgenic algae group (vp28-7120 group) was continuously immunized [continuous immunization for 0 days (vp28-7120-0d); continuous immunization for 2 days (vp28-7120-2d); continuous immunization for 4 days (vp28-7120-4d)]. After seven days, the daily survival rate of each experimental group was continuously tracked. Following the viral challenge, the hepatopancreas samples were assayed for their levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), thioredoxin peroxidase (TPX), acid phosphatase (ACP), and alkaline phosphatase (AKP) at varying time intervals. In comparison to the positive control group (challenge and no vaccination) and the wild-type group (challenge, fed wild-type Anabaena sp. PCC7120), the vp28-7120 group (challenge, fed trans-vp28 gene Anabaena sp. PCC7120) exhibited a remarkable increase in survival rates, reaching 50 % (vp28-7120-0d), 76.67 % (vp28-7120-2d), and 80 % (vp28-7120-4d). Furthermore, the vp28-7120 group consistently displayed significantly higher activities of SOD, CAT, GSH-Px, ACP, and AKP, while exhibiting notably lower TPX activity, when compared to the control group. These results indicate that the Pcpc560 promoter effectively elevated the expression level of the exogenous vp28 gene and spurred the growth of the trans-vp28 gene Anabaena sp. PCC7120. Consequently, trans-vp28 gene Anabaena sp. PCC7120 significantly bolstered the immunity of L.vannamei. Therefore, utilizing the Pcpc560 promoter to develop trans-vp28 gene Anabaena sp. PCC7120 based oral vaccine is highly beneficial for industrial-scale cultivation, advancing its commercialization prospects.

2.
Inorg Chem ; 63(43): 20501-20509, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39403728

RESUMO

Nanocluster catalysts typically face challenges in balancing stability with catalytic efficiency. This study introduces a unique bismuth-oxo cluster, solely protected by two ring-opened calixarenes, which demonstrates not only enhanced structural stability but also superior catalytic performance in the sustained conversion of CO2 to HCOOH via electrocatalysis. For the first time, we reveal that under specific solvothermal conditions, tert-butylcalix[8]arene (TBC[8]) can undergo in situ oxidative cleavage of its C-C bond, leading to ring-opened polyphenolic molecules. These molecules serve as protective ligands for the bismuth-oxo cluster, bestowing exceptional structural stability and offering a more flexible and diverse configuration compared to intact TBC[8]. This adaptability promotes the exposure of active bismuth sites on the cluster surface, enhancing catalytic efficiency. Notably, the Bi10 cluster, featuring a monobismuth active site, achieves an exceptional formate production efficiency of 98.79% at -1.25 V vs RHE while maintaining superb durability over 8 h. The stability and catalytic processes of Bi10 surpass those of the Bi13 cluster, which is structurally reinforced by two intact TBC[8] molecules and stabilized by four benzoic ligands. Through in situ infrared spectroscopy and density functional theory calculations, we demonstrate that the monobismuth active site in Bi10 more effectively stabilizes the *OCHO intermediate, thereby promoting the electrocatalytic reduction of CO2 to HCOOH compared to Bi13. This comparative performance underscores the potential of ring-opened calixarene ligands in enhancing the functionality of nanocluster catalysts.

3.
Radiology ; 308(2): e223003, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37552073

RESUMO

Background The Ovarian-Adnexal Reporting and Data System (O-RADS) has limited specificity for malignancy. Contrast-enhanced US can help distinguish malignant from benign lesions, but its added value to O-RADS has not yet been assessed. Purpose To establish a diagnostic model combining O-RADS and contrast-enhanced US and to validate whether O-RADS plus contrast-enhanced US has a better diagnostic performance than O-RADS alone. Materials and Methods This prospective study included participants from May 2018 to March 2021 who underwent contrast-enhanced US before surgery and had lesions categorized as O-RADS 3, 4, or 5 by US, with a histopathologic reference standard. From April 2021 to July 2022, participants with pathologically confirmed ovarian-adnexal lesions were recruited for the validation group. In the pilot group, the initial enhancement time and enhancement intensity in comparison with the uterine myometrium, contrast agent distribution pattern, and dynamic changes in enhancement of lesions were assessed. Contrast-enhanced US features were used to calculate contrast-enhanced US scores for benign (score ≤2) and malignant (score ≥4) lesions. Lesions were then re-rated according to O-RADS category plus contrast-enhanced US scores. Receiver operating characteristic curves were constructed and compared using the DeLong method. The combined system was validated in an independent group. Results The pilot group included 76 women (mean age, 44 years ± 13 [SD]), and the validation group included 46 women (mean age, 42 years ± 14). Differences in initial enhancement time (P < .001), enhancement intensity (P < .001), and dynamic changes in enhancement (P < .001) between benign and malignant lesions were observed in the pilot group. Contrast-enhanced US scores were calculated using these features. The O-RADS risk stratification was upgraded one level for contrast-enhanced US scores of 4 or more and downgraded one level for contrast-enhanced US scores of 2 or less. In the validation group, the diagnostic performance of O-RADS plus contrast-enhanced US score was higher (area under the receiver operating characteristic curve [AUC] = 0.93) than O-RADS (AUC = 0.71, P < .001). Conclusion Contrast-enhanced US improved the diagnostic performance for malignancy of the O-RADS categories 3-5. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Grant in this issue.


Assuntos
Neoplasias , Humanos , Feminino , Adulto , Estudos Prospectivos , Estudos Retrospectivos , Curva ROC , Medição de Risco , Sensibilidade e Especificidade , Ultrassonografia/métodos
4.
Acta Pharmacol Sin ; 44(6): 1277-1289, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36517670

RESUMO

Neoplastic cells of non-immunogenic pancreatic ductal adenocarcinoma (PDAC) express indoleamine 2,3-dioxygenase 1 (IDO-1), an immunosuppressive enzyme. The metabolites of IDO-1 in cancers provide one-carbon units that annihilate effector T cells, and recruit immunosuppressive cells. In this study we investigated how IDO-1 affected the neoplastic cell behaviors in PDACs. Using multiple markers co-labeling method in 45-µm-thick tissue sections, we showed that IDO-1 expression was uniquely increased in the neoplastic cells extruded from ducts' apical or basal domain, but decreased in lymph metastatic cells. IDO-1+ extruding neoplastic cells displayed increased vimentin expression and decreased cytokeratin expression in PDACs, characteristics of epithelial-mesenchymal transition (EMT). However, IDO-1 expression was uncorrelated with immunosuppressive infiltrates and clinicopathological characteristics of grim outcome. We replicated basal extrusion with EMT in murine KPIC PDAC organoids by long-term IFN-γ induction; application of IDO-1 inhibitor INCB24360 or 1-MT partially reversed basal extrusion coupled EMT. Ido-1 deletion in KPIC cells deprived its tumorigenicity in immunocompetent mice, decreased cellular proliferation and macropinocytic ability, and increased immunogenicity. KPIC organoids with IFN-γ-induced basal extrusion did not accelerate distant metastasis, whereas inhibition IFN-γ-induced IDO-1 with INB24360 but not 1-MT in KPIC organoids elicited liver metastasis of subcutaneous KPIC organoid tumors, suggesting that lower IDO-1 activity accelerated distant metastasis, whereas IDO-1 was indispensable for tumorigenicity of PDAC cells and supports the survival of extruding cells.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Fatores Imunológicos , Neoplasias Pancreáticas
5.
Can Vet J ; 64(1): 81-83, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36593934

RESUMO

A 7-year-old intact female domestic medium hair cat was examined at a veterinary clinic for a scabbed nodule over the right shoulder. Multiple nodules recurred at the same site after the first surgical excision, and a second surgical excision was performed. Histopathology demonstrated high-mitotic-rate neoplastic cells and therefore a histiocytic proliferative disease was initially suspected. The condition progressed rapidly within a 5-month period and the cat was euthanized due to sudden onset of severe dyspnea. Necropsy showed diffuse metastatic nodules in the lungs, confirming a histiocytic proliferative disease, with histiocytic sarcoma being the most likely differential diagnosis.


Un cas rare de maladie histiocytaire proliférative chez un chat. Une chatte domestique á poil moyen intacte de 7 ans a été examinée dans une clinique vétérinaire pour un nodule croûteux sur l'épaule droite. Plusieurs nodules sont réapparus au même site après la première excision chirurgicale, et une deuxième excision chirurgicale a été réalisée. L'histopathologie a mis en évidence des cellules néoplasiques á taux mitotique élevé et, par conséquent, une maladie proliférative histiocytaire a été initialement suspectée. L'état a progressé rapidement en l'espace de 5 mois et le chat a été euthanasié en raison de l'apparition soudaine d'une dyspnée sévère. L'autopsie a montré des nodules métastatiques diffus dans les poumons, confirmant une maladie proliférative histiocytaire, le sarcome histiocytaire étant le diagnostic différentiel le plus probable.(Traduit par Dr Serge Messier).


Assuntos
Doenças do Gato , Sarcoma Histiocítico , Feminino , Gatos , Animais , Recidiva Local de Neoplasia/veterinária , Sarcoma Histiocítico/diagnóstico , Sarcoma Histiocítico/cirurgia , Sarcoma Histiocítico/veterinária , Evolução Fatal , Pulmão/patologia , Diagnóstico Diferencial , Doenças do Gato/diagnóstico , Doenças do Gato/cirurgia , Doenças do Gato/patologia
6.
BMC Pregnancy Childbirth ; 22(1): 538, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35787798

RESUMO

BACKGROUND: Perinatal complications are common burdens for neonates born from mother with pPROM. Physicians and parents sometimes need to make critical decisions about neonatal care with short- and long-term implications on infant's health and families and it is important to predict severe neonatal outcomes with high accuracy. METHODS: The study was based on our prospective study on 1001 preterm infants born from mother with pPROM from August 1, 2017, to March 31, 2018 in three hospitals in China. Multivariable logistic regression analysis was applied to build a predicting model incorporating obstetric and neonatal characteristics available within the first day of NICU admission. We used enhanced bootstrap resampling for internal validation. RESULTS: One thousand one-hundred pregnancies with PROM at preterm with a single fetus were included in our study. SNO was diagnosed in 180 (17.98%) neonates. On multivariate analysis of the primary cohort, independent factors for SNO were respiratory support on the first day,, surfactant on day 1, and birth weight, which were selected into the nomogram. The model displayed good discrimination with a C-index of 0.838 (95%CI, 0.802-0.874) and good calibration performance. High C-index value of 0.835 could still be reached in the internal validation and the calibration curve showed good agreement. Decision curve analysis showed if the threshold is > 15%, using our model would achieve higher net benefit than model with birthweight as the only one predictor. CONCLUSION: Variables available on the first day in NICU including respiratory support on the first day, the use of surfactant on the first day and birthweight could be used to predict the risk of SNO in infants born from mother with pPROM with good discrimination and calibration performance.


Assuntos
Recém-Nascido Prematuro , Mães , Peso ao Nascer , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Lactente , Recém-Nascido , Gravidez , Estudos Prospectivos , Tensoativos
7.
World J Surg Oncol ; 20(1): 183, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668494

RESUMO

BACKGROUND: Transforming growth factor (TGF)-ß signaling functions importantly in regulating tumor microenvironment (TME). This study developed a prognostic gene signature based on TGF-ß signaling-related genes for predicting clinical outcome of patients with lung adenocarcinoma (LUAD). METHODS: TGF-ß signaling-related genes came from The Molecular Signature Database (MSigDB). LUAD prognosis-related genes were screened from all the genes involved in TGF-ß signaling using least absolute shrinkage and selection operator (LASSO) Cox regression analysis and then used to establish a risk score model for LUAD. ESTIMATE and CIBERSORT analyzed infiltration of immune cells in TME. Immunotherapy response was analyzed by the TIDE algorithm. RESULTS: A LUAD prognostic 5-gene signature was developed based on 54 TGF-ß signaling-related genes. Prognosis of high-risk patients was significantly worse than low-risk patients. Both internal validation and external dataset validation confirmed a high precision of the risk model in predicting the clinical outcomes of LUAD patients. Multivariate Cox analysis demonstrated the model independence in OS prediction of LUAD. The risk model was significantly related to the infiltration of 9 kinds of immune cells, matrix, and immune components in TME. Low-risk patients tended to respond more actively to anti-PD-1 treatment, while high-risk patients were more sensitive to chemotherapy and targeted therapy. CONCLUSIONS: The 5-gene signature based on TGF-ß signaling-related genes showed potential for LUAD management.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/terapia , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Prognóstico , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral/genética
8.
Molecules ; 28(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36615244

RESUMO

Cell death is a fundamental pathophysiological process in human disease. The discovery of necroptosis, a form of regulated necrosis that is induced by the activation of death receptors and formation of necrosome, represents a major breakthrough in the field of cell death in the past decade. Z-DNA-binding protein (ZBP1) is an interferon (IFN)-inducing protein, initially reported as a double-stranded DNA (dsDNA) sensor, which induces an innate inflammatory response. Recently, ZBP1 was identified as an important sensor of necroptosis during virus infection. It connects viral nucleic acid and receptor-interacting protein kinase 3 (RIPK3) via two domains and induces the formation of a necrosome. Recent studies have also reported that ZBP1 induces necroptosis in non-viral infections and mediates necrotic signal transduction by a unique mechanism. This review highlights the discovery of ZBP1 and its novel findings in necroptosis and provides an insight into its critical role in the crosstalk between different types of cell death, which may represent a new therapeutic option.


Assuntos
Necroptose , Necrose , Humanos , Necrose/tratamento farmacológico , Necrose/metabolismo , Viroses/metabolismo
9.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1039-1050, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35285205

RESUMO

This study analyzed the molecular mechanism of Huangjing Qianshi Decoction(HQD) in the treatment of prediabetes based on network pharmacology and molecular docking. The active components of HQD were identified and screened based on Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP, http://Lsp.nwu.edu.cn/tcmsp.php) and then the targets of the components and the genes related to prediabetes were retrieved, followed by identifying the common targets of the decoction and the disease. The medicinal component-target network was constructed by Cytoscape to screen key components. The protein-protein interaction(PPI) network was established by STRING and hub genes were identified by Cytoscape-CytoNCA, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) of the hub genes with R-clusterProfi-ler. Thereby, the possible signaling pathways were predicted and the molecular mechanism was deduced. A total of 79 active components of HQD and 785 diabetes-related targets of the components were screened out. The hub genes mainly involved the GO terms of tricarboxylic acid cycle, peptide binding, amide binding, hydrolase activity, and kinase activity regulation, and the KEGG pathways of AGE-RAGE signaling pathway, TNF signaling pathway, AMPK signaling pathway, IL-17 signaling pathway, and insulin signaling pathway. Western blot result showed that HQD-containing serum significantly reduced the expression of AKT1, AGE, and RAGE proteins in insulin resistance model cells. HQD's treatment of prediabetes is characterized by multiple pathways, multiple targets, and multiple levels. The main mechanism is that the components zhonghualiaoine, baicalein, kaempferol, and luteolin act on AKT1 and inhibit the AGE-RAGE axis.


Assuntos
Medicamentos de Ervas Chinesas , Estado Pré-Diabético , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Farmacologia em Rede , Estado Pré-Diabético/tratamento farmacológico , Estado Pré-Diabético/genética
10.
Nanotechnology ; 32(21)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33535194

RESUMO

An asymmetric dual-gate (DG) MoS2field-effect transistor (FET) with ultrahigh electrical performance and optical responsivity using atomic-layer-deposited HfO2as a top-gate (TG) dielectric was fabricated and investigated. The effective DG modulation of the MoS2FET exhibited an outstanding electrical performance with a high on/off current ratio of 6 × 108. Furthermore, a large threshold voltage modulation could be obtained from -20.5 to -39.3 V as a function of the TG voltage in a DG MoS2phototransistor. Meanwhile, the optical properties were systematically explored under a series of gate biases and illuminated optical power under 550 nm laser illumination. An ultrahigh photoresponsivity of 2.04 × 105AW-1has been demonstrated with the structure of a DG MoS2phototransistor because the electric field formed by the DG can separate photogenerated electrons and holes efficiently. Thus, the DG design for 2D materials with ultrahigh photoresponsivity provides a promising opportunity for the application of optoelectronic devices.

11.
Mamm Genome ; 31(3-4): 110-116, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32318815

RESUMO

RNA polymerase III is an essential enzyme in eukaryotes for synthesis of tRNA, 5S rRNA, and other small nuclear and cytoplasmic RNAs. Thus, RNA polymerase III promoters are often used in small hairpin RNA (shRNA) expression. In this study, the porcine H1, U6, and 7SK RNA polymerase III type promoters were cloned into a pcDNA3.1( +) expression vector containing a shRNA sequence targeting enhanced green fluorescent protein (EGFP). PK and DF-1 cells were cotransfected with the construction of recombinant interference expression vector and the EGFP expression vector, pEGFP-N1. The average fluorescence intensity of EGFP in transfected cells was measured by fluorescence microscopy and flow cytometry. Real-time PCR was used to detect expressed shRNAs and the relative expression of EGFP, to confirm the activity of the promoters. The results showed that the activity of porcine 7SK promoter is stronger than the U6 promoter, which is in turn stronger than porcine H1. While the high levels of expression of the U6 and 7SK promoters saturate the shRNAs level in the host cell, which can cause cytotoxicity and tissue damage. Therefore, porcine H1 promoter is effective for expression of shRNA, and may be an excellent tool to knockdown gene expression in pigs for functional genomics studies. The results also lay a foundation for the development of porcine RNAi technology and genetically modified porcine research.


Assuntos
Expressão Gênica/genética , Regiões Promotoras Genéticas/genética , RNA Polimerase III/genética , RNA Interferente Pequeno/genética , Animais , Sequência de Bases , Linhagem Celular , Terapia Genética/métodos , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Interferência de RNA/fisiologia , Suínos , Transfecção/métodos
12.
Nanotechnology ; 31(27): 275301, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32187587

RESUMO

Atomically multilayered two-dimensional transition-metal carbides have abundant interfaces, and are very promising as outstanding electromagnetic absorbing materials at thin thickness. Here, a Ti3C2Tx MXene was prepared by hydrofluoric acid etching method, and has typical multilayered morphology with stacks of nanosheets. The microwave dielectric behaviours of the Ti3C2Tx with efficient microwave absorption were investigated. The Ti3C2Tx presents good impedance matching, achieved with effective absorption bandwidth covering from 12.4 GHz to 17.1 GHz, with thickness of only 1.5 mm, which nearly covers the whole Ku band. The microwave absorption performance was adjusted, and the Ti3C2Tx has a minimum reflection loss of -34.4 dB at 12 GHz at only 1.7 mm. This study demonstrates the real potential of Ti3C2Tx MXene materials as electromagnetic wave thin broadband absorbers.

13.
J Cell Mol Med ; 23(7): 4653-4665, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31044530

RESUMO

Severe reduction in the ß-cell number (collectively known as the ß-cell mass) contributes to the development of both type 1 and type 2 diabetes. Recent pharmacological studies have suggested that increased pancreatic ß-cell proliferation could be due to specific inhibition of adenosine kinase (ADK). However, genetic evidence for the function of pancreatic ß-cell ADK under physiological conditions or in a pathological context is still lacking. In this study, we crossed mice carrying LoxP-flanked Adk gene with Ins2-Cre mice to acquire pancreatic ß -cell ADK deficiency (Ins2-Cre± Adkfl/fl ) mice. Our results revealed that Ins2-Cre+/- Adkfl/fl mice showed improved glucose metabolism and ß-cell mass in younger mice, but showed normal activity in adult mice. Moreover, Ins2-Cre± Adkfl/fl mice were more resistant to streptozotocin (STZ) induced hyperglycaemia and pancreatic ß-cell damage in adult mice. In conclusion, we found that ADK negatively regulates ß-cell replication in young mice as well as under pathological conditions, such as STZ induced pancreatic ß-cell damage. Our study provided genetic evidence that specific inhibition of pancreatic ß-cell ADK has potential for anti-diabetic therapy.


Assuntos
Adenosina Quinase/genética , Deleção de Genes , Glucose/metabolismo , Homeostase , Hiperglicemia/induzido quimicamente , Hiperglicemia/enzimologia , Células Secretoras de Insulina/enzimologia , Envelhecimento/patologia , Animais , Contagem de Células , Proliferação de Células , Camundongos Knockout , Estreptozocina , Fatores de Tempo
14.
Metab Eng ; 54: 69-82, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30914380

RESUMO

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a promising biopolyester with good mechanical properties and biodegradability. Large-scale production of PHBV is still hindered by the high production cost. CRISPR/Cas9 method was used to engineer the TCA cycle in Halomonas bluephagenesis on its chromosome for production of PHBV from glucose as a sole carbon source. Two TCA cycle related genes sdhE and icl encoding succinate dehydrogenase assembly factor 2 and isocitrate lysase were deleted, respectively, in H. bluephagenesis TD08AB containing PHBV synthesis genes on the chromosome, to channel more flux to increase the 3-hydroxyvalerate (3HV) ratio of PHBV. Due to a poor growth behavior of the mutant strains, H. bluephagenesis TY194 equipped with a medium strength Pporin-194 promoter was selected for further studies. The sdhE and/or icl mutant strains of H. bluephagenesis TY194 were constructed to show enhanced cell growth, PHBV synthesis and 3HV molar ratio. Gluconate was used to activate ED pathway and thus TCA cycle to increase 3HV content. H. bluephagenesis TY194 (ΔsdhEΔicl) was found to synthesize 17mol% 3HV in PHBV. Supported by the synergetic function of phosphoenolpyruvate carboxylase and Vitreoscilla hemoglobin encoded by genes ppc and vgb inserted into the chromosome of H. bluephagenesis TY194 (ΔsdhE) serving to enhance TCA cycle activity, a series of strains were generated that could produce PHBV containing 3-18mol% 3HV using glucose as a sole carbon source. Shake flask studies showed that H. bluephagenesis TY194 (ΔsdhE, G7::Pporin-ppc) produced 6.3 g/L cell dry weight (CDW), 65% PHBV in CDW and 25mol% 3HV in PHBV when grown in glucose and gluconate. 25mol% 3HV was the highest reported via chromosomal expression system. PHBV copolymers with different 3HV molar ratios were extracted and characterized. Next-generation industrial biotechnology (NGIB) based on recombinant H. bluephagenesis grown under unsterile and continuous conditions, allows production of P(3HB-0∼25mol% 3HV) in a convenient way with reduced production complexity and cost.


Assuntos
Cromossomos Bacterianos , Ciclo do Ácido Cítrico/genética , Engenharia Genética , Halomonas , Poliésteres/metabolismo , Ácido 3-Hidroxibutírico/genética , Ácido 3-Hidroxibutírico/metabolismo , Cromossomos Bacterianos/genética , Cromossomos Bacterianos/metabolismo , Halomonas/genética , Halomonas/metabolismo , Ácidos Pentanoicos/metabolismo
15.
Zygote ; 27(3): 143-152, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31182178

RESUMO

SummaryMuch effort has been devoted to improving the efficiency of animal cloning. The aim of this study was to investigate the effect of BRG1 contained in Xenopus egg extracts on the development of cloned mouse embryos. The results showed that mouse NIH/3T3 cells were able to express pluripotent genes after treatment with egg extracts, indicating that the egg extracts contained reprogramming factors. After co-injection of Xenopus egg extracts and single mouse cumulus cells into enucleated mouse oocytes, statistically higher pronucleus formation and development rates were observed in the egg Extract- co-injected group compared with those in the no egg extract-injected (NT) group (38-66% vs 18-34%, P<0.001). Removal of BRG1 protein from Xenopus egg extracts was conducted, and the BRG1-depleted extracts were co-injected with single donor cells into recipient oocytes. The results showed that the percentages of pronucleus formation were significantly higher in both BRG1-depleted and BRG1-intact groups than that in the nuclear transfer (NT) group (94, 64% vs 50%, P<0.05). Furthermore, percentages in the BRG1-depleted group were even higher than in the BRG1-intact group (94% vs 64%). More confined expression of Oct4 in the inner cell mass (ICM) was observed in the blastocyst derived from the egg extract-injected groups. However, Nanog expression was more contracted in the ICM of cloned blastocysts in the BRG1-depleted group than in the BGR1-intact group. Based on the present study, BRG1 might not play an essential role in reprogramming, but the factors enhancing pronucleus formation and development of cloned mouse embryos are contained in Xenopus egg extracts.


Assuntos
Blastocisto/citologia , Extratos Celulares/química , Oócitos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Xenopus laevis/metabolismo , Animais , Blastocisto/metabolismo , Fator 1 de Resposta a Butirato , Clonagem de Organismos/métodos , Células do Cúmulo/metabolismo , Desenvolvimento Embrionário , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Células NIH 3T3 , Técnicas de Transferência Nuclear , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Oócitos/citologia , Proteínas de Ligação a RNA/genética
16.
J Biol Chem ; 291(35): 18176-89, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27387502

RESUMO

Activation of IKKß is the key step in canonical activation of NF-κB signaling. Extensive work has provided insight into the mechanisms underlying IKKß activation through the identification of context-specific regulators. However, the molecular processes responsible for its negative regulation are not completely understood. Here, we identified KLHL21, a member of the Kelch-like gene family, as a novel negative regulator of IKKß. The expression of KLHL21 was rapidly down-regulated in macrophages upon treatment with proinflammatory stimuli. Overexpression of KLHL21 inhibited the activation of IKKß and degradation of IκBα, whereas KLHL21 depletion via siRNA showed the opposite results. Coimmunoprecipitation assays revealed that KLHL21 specifically bound to the kinase domain of IKKß via its Kelch domains and that this interaction was gradually attenuated upon TNFα treatment. Furthermore, KLHL21 did not disrupt the interaction between IKKß and TAK1, TRAF2, or IκBα. Also, KLHL21 did not require its E3 ubiquitin ligase activity for IKKß inhibition. Our findings suggest that KLHL21 may exert its inhibitory function by binding to the kinase domain and sequestering the region from potential IKKß inducers. Taken together, our data clearly demonstrate that KLHL21 negatively regulates TNFα-activated NF-κB signaling via targeting IKKß, providing new insight into the mechanisms underlying NF-κB regulation in cells.


Assuntos
Quinase I-kappa B/metabolismo , Proteínas dos Microfilamentos/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos , Quinase I-kappa B/genética , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Proteínas dos Microfilamentos/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Células RAW 264.7 , Fator 2 Associado a Receptor de TNF/genética , Fator 2 Associado a Receptor de TNF/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
17.
J Am Chem Soc ; 139(24): 8312-8319, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28538098

RESUMO

Two-dimensional metal-organic framework (MOF) nanosheets are utilized as effective enzyme inhibitors, providing an inspiring means to enhance the control of cellular processes as well as improve our understanding of the surface chemistry between MOFs and enzymes. In this paper, we demonstrated that the activity of α-chymotrypsin (ChT) can be effectively inhibited with 96.9% inhibition by 2-D Cu(bpy)2(OTf)2 nanosheets, while Zn2(bim)4 nanosheets show no significant inhibition effect toward ChT. Kinetic studies revealed that the material acts as a competitive inhibitor toward ChT. Furthermore, fluorescence and circular dichroism spectroscopy reveal that the 2-D MOF nanosheets do not change the secondary structure of the enzyme. The Cu(II) center of the 2-D nanosheets binds the 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) molecules in the buffer, leading to an electrostatic interaction between the nanosheets and the enzyme. In addition, the irreversible coordination interactions between Cu(II) center and His-57 played an important role during the inhibition process, as supported by ionic strength experiments and UV absorbance changes of Cu(II) d-d transitions. As a result, the substrate is prevented from reaching the active sites of the enzyme causing enzyme inhibition. The modulation of enzyme activity by 2-D MOF nanosheets opens up a new direction for the exploration of the MOF-bio interface in physiological and catalytic systems.


Assuntos
Quimotripsina/antagonistas & inibidores , Quimotripsina/metabolismo , Estruturas Metalorgânicas/farmacologia , Nanoestruturas/química , Inibidores de Serina Proteinase/farmacologia , Cinética , Estruturas Metalorgânicas/química , Modelos Moleculares , Estrutura Molecular , Concentração Osmolar , Tamanho da Partícula , Inibidores de Serina Proteinase/química
18.
Arch Virol ; 162(4): 1025-1029, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27990566

RESUMO

Qinghai Lake is a major migratory-bird breeding site that has experienced several highly pathogenic avian influenza virus (AIV) epizootics. Plateau pikas (Ochotona curzoniae) have previously been implicated in the ecology of avian influenza virus in this region. We first isolated an H9N2 AIV (A/Pika/Menyuan/01/2008) from plateau pikas between November 2008 and October 2009. Sequence analysis showed that the A/Pika/Menyuan/01/2008 AIV was closely related to the H9N2 AIV strain (A/Turkey/Wisconsin/ 1/1966). Our findings suggested that plateau pikas may contribute to AIV epidemiology in the Qinghai Lake region.


Assuntos
Doenças das Aves/transmissão , Reservatórios de Doenças/veterinária , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Lagomorpha/virologia , Animais , Animais Selvagens/virologia , Doenças das Aves/virologia , Embrião de Galinha , China , Reservatórios de Doenças/virologia , Vetores de Doenças , Vírus da Influenza A Subtipo H9N2/classificação , Lagos , Filogenia , Proteínas Virais/genética
19.
Microbiol Immunol ; 60(12): 835-845, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27981613

RESUMO

Dengue virus (DENV) is still a major threat to human health in most tropical and subtropical countries and regions. In the present study, a multi-epitope DNA vaccine that encodes 15 immunogenic and conserved HLA-A*0201-, HLA-A*1101-, HLA-A*2402-restricted CTL epitopes from DENV serotype 1 (DENV-1) was constructed based on the eukaryotic expressing plasmid pcDNATM 3.1/myc-His(-) A. Immunization of HLA-A*0201, HLA-A*1101 and HLA-A*2402 transgenic mice with the recombinant plasmid pcDNATM 3.1/myc-His(-) A-DENV-1-Meg resulted in significantly greater IFN-γ-secreting T-cell responses against most (14/15) CTL epitopes than occurred in mice immunized with the empty plasmid pcDNATM 3.1/myc-His(-) A. Additionally, the epitope-specific T cells directed to some epitopes secreted not only IFN-γ but also IL-6 and/or TNF-α. Finally, the induced epitope-specific T cells also efficiently lysed epitope-pulsed splenocytes and DENV-1-infected splenic monocytes. The present study confirms the immunogenicity of multi-epitope DENV vaccine, suggesting that it may contribute to the development of a universal DENV vaccine.


Assuntos
Vírus da Dengue/imunologia , Epitopos de Linfócito T/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinas de DNA/imunologia , Animais , Testes Imunológicos de Citotoxicidade , Vírus da Dengue/genética , Epitopos de Linfócito T/genética , Feminino , Antígenos HLA-A/genética , Humanos , Interferon gama/metabolismo , Interleucina-6/metabolismo , Camundongos Transgênicos , Fator de Necrose Tumoral alfa/metabolismo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
20.
Biomed Environ Sci ; 29(10): 767-772, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27927278

RESUMO

In the present study, the complete genomes of four common (4/EV71/Wenzhou/CHN/2014, 15/ EV71/Wenzhou/CHN/2014, 116/EV71/Wenzhou/ CHN/2014, and 120/EV71/Wenzhou/CHN/2014) and two virulent (11/EV71/Wenzhou/CHN/2014 and 109/EV71/Wenzhou/CHN/2014) enterovirus 71 (EV71) isolates were sequenced and described. They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster). Nucleotide sequence alignment revealed six nucleotide variations (GP151→TP151, GP199→AP199, GP261→TP261, AP328→CP328, GP422→AP422, and GP437→TP437) in the two virulent isolates within the 5'UTR of the IRES element. RNA secondary structure predictions of IRES and FCE indicated that the common isolates shared similar structures, which were different from those of the virulent isolates. Moreover, the GP114→CP114 and GP151→TP151 mutations in the virulent isolates contributed to the formation of the unique RNA secondary structures in SL II. Furthermore, nucleotide/amino acid sequence alignments of 82 EV71 isolates indicated that six sites (TP488 and CP577 in the 5'UTR; AsnP57 in 2A; IleP56 in 3C; CP10 and AP47 in the 3'UTR) are potentially associated with the neurovirulence of EV71. Finally, the 3D structures of 2A were analogous, whereas the structures of VP1 and 3C were variable.


Assuntos
Sistema Nervoso Central/virologia , Enterovirus Humano A/genética , Infecções por Enterovirus/virologia , Genoma Viral , Sequência de Bases , Enterovirus Humano A/classificação , Enterovirus Humano A/isolamento & purificação , Enterovirus Humano A/patogenicidade , Genômica , Genótipo , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , RNA Viral/química , RNA Viral/genética , Virulência
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