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1.
J Agric Food Chem ; 72(1): 493-503, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38109329

RESUMO

The strategy of active aggregation tag fusion expression with target proteins can solve the problems of restricted expression, inefficient purification, and laborious immobilization faced in the production of recombinant proteins in Escherichia coli. We localized a novel active aggregation peptide HlyA60 from the hemolysin A secretion system, which can effectively induce aggregate formation with satisfactory protein activities in E. coli after fusion expression with the protein of interest. Based on structural prediction and surface properties, the process of active aggregation of HlyA60 through electrostatic interactions and hydrophobic interactions was analyzed. To investigate the potential application of HlyA60 as an efficient aggregation tag, it was fused with acetyl xylan esterase and lipase A, separately. The resulting fusion proteins demonstrated active aggregation rates of 97.6 and 66.7%, respectively, leading to 1.9-fold and 1.7-fold increases in bacterial density at the end of fermentation. The AXE-HlyA60 fusion protein, which exhibited superior performance, was subjected to purification and immobilization. It was able to achieve column-free purification with an impressive 98.8% recovery and in situ immobilization; the immobilization enabled 30 cycles of reactions to take place with 85% residual activity maintained. Our findings provide a novel tool for efficiently producing recombinant proteins in E. coli.


Assuntos
Escherichia coli , Agregados Proteicos , Escherichia coli/metabolismo , Proteínas Recombinantes de Fusão/química , Peptídeos/metabolismo , Biossíntese de Proteínas
2.
J Agric Food Chem ; 71(48): 18919-18927, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37991146

RESUMO

Nootkatone is a type of valuable sesquiterpene that is widely used in food, cosmetics, fragrance, and other fields. The industry is faced with a major challenge due to the high expenses associated with plant-extracted nootkatone. We have developed a fermentation process for valencene production using seaweed hydrolysate as a carbon source via engineered Saccharomyces cerevisiae. Reduced-pressure distillation purified valencene was used as a substrate, and a yeast strain carrying HPO/AtCPR1 and ADH genes was constructed for whole-cell catalysis. After biotransformation at 25 °C for 3 h, a high yield of 73% for nootkatone production was obtained. Further, simple rotary evaporation was used to obtain nootkatone with a high purity of 97.4%. Mosquito-repellent testing showed that 1% nootkatone has a mosquito-repellent effect lasting up to 6 h, which is comparable to the 20% N,N-diethyl-meta-toluamide (DEET) effect. This study provided practical experience for developing third-generation biomass resources, generating new ideas for green manufacturing of valuable chemical products, and serving as a reference for creating efficient and eco-friendly mosquito repellents.


Assuntos
Repelentes de Insetos , Inseticidas , Sesquiterpenos , Sesquiterpenos Policíclicos , Sesquiterpenos/metabolismo , DEET , Verduras/metabolismo , Saccharomyces cerevisiae/metabolismo
4.
Apoptosis ; 28(9-10): 1406-1421, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37462883

RESUMO

Endoplasmic reticulum (ER) stress has been implicated in the mechanisms underlying the fibrotic process in dilated cardiomyopathy (DCM) and results in disease exacerbation; however, the molecular details of this mechanism remain unclear. Through microarray and bioinformatic analyses, we explored genetic alterations in myocardial fibrosis (MF) and identified potential biomarkers related to ER stress. We integrated two public microarray datasets, including 19 DCM and 16 control samples, and comprehensively analyzed differential expression, biological functions, molecular interactions, and immune infiltration levels. The immune cell signatures suggest that inflammatory immune imbalance may promote MF progression. Both innate and adaptive immunity are involved in MF development, and T-cell subsets account for a considerable proportion of immune infiltration. The immune subtypes were further compared, and 103 differentially expressed ER stress-related genes were identified. These genes were mainly enriched in neuronal apoptosis, protein modification, oxidative stress reaction, glycolysis and gluconeogenesis, and NOD-like receptor signaling pathways. Furthermore, the 15 highest-scoring core genes were identified. Seven hub genes (AK1, ARPC3, GSN, KPNA2, PARP1, PFKL, and PRKC) might participate in immune-related mechanisms. Our results offer a new integrative view of the pathways and interaction networks of ER stress-related genes and provide guidance for developing novel therapeutic strategies for MF.


Assuntos
Cardiomiopatia Dilatada , Humanos , Cardiomiopatia Dilatada/genética , Apoptose , Transdução de Sinais/genética , Estresse do Retículo Endoplasmático/genética , Imunidade
5.
Diagnostics (Basel) ; 12(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36553149

RESUMO

OBJECTIVE: Esophageal dysmotility is a common and neglected complication of systemic sclerosis (SSc) associated with poor prognosis, while the assessment remains a challenge. We aimed to develop a diagnostic model for esophageal dysmotility in SSc patients that provides individualized risk estimates. METHODS: Seventy-five SSc patients who underwent high-resolution manometry (HRM) were included in the study. Esophageal widest diameter (WED) was measured on a chest CT scan. Esophageal parameters between patients with and without esophageal dysmotility were compared. Multivariate logistic regression analysis and Least Absolute Shrinkage and Selection Operator (LASSO) regression were used to fit the model. The diagnostic model was evaluated by discrimination and calibration. Internal validation was estimated using the enhanced bootstrap method with 1000 repetitions. RESULTS: Sixty-one systemic sclerosis patients (81.3%) were diagnosed with esophageal dysmotility according to the Chicago Classification v 3.0. The diagnostic model for evaluating the probability of esophageal dysmotility integrated clinical and imaging features, including disease duration, ILD, and WED. The model displayed good discrimination with an area under the curve (AUC) of 0.923 (95% CI: 0.837-1.000), a Brier score of 0.083, and good calibration. A high AUC value of 0.911 could still be achieved in the internal validation. CONCLUSION: The diagnostic model, which combines the disease duration, ILD, and imaging feature (WED), is an effective and noninvasive method for predicting esophageal dysmotility in SSc patients.

6.
Carbohydr Polym ; 297: 120029, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36184175

RESUMO

In this study, corn starch (40 % moisture content) was placed in an ultra-high magnetic field(UMF)(5-20 T) to investigate the ordering and stabilization process under the magnetic field. With the increase of the intensity of UMF, C-OH and O-C-O were oxidized to O = C-OH and cross-linked to form ester bonds. When the UMF intensity was 15 T, the effect was the most significant with the ordered short-range structures formed; since the O = C-OR enhanced carbon skeleton structure, the crystallinity increased comparatively and amylose content reached the minimum value (15.32 ± 0.04 %). Additionally, UMF has a compressive effect on the void structure of A-type starch, and the average particle size decreased. RVA and DSC demonstrated that the UMF-treated starch had better thermal stability and shear resistance. This study suggested that UMF could serve as a prospective technique for starch product processing.


Assuntos
Amilose , Amido , Amilose/química , Carbono , Ésteres , Campos Magnéticos , Estudos Prospectivos , Amido/química , Zea mays/química
7.
Pharmaceutics ; 14(7)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35890334

RESUMO

Chronic hepatitis B is a critical cause of many serious liver diseases such as hepatocellular carcinoma (HCC). The main challenges in hepatitis B treatment include the rebound of hepatitis B virus (HBV)-related antigen levels after drug withdrawal and the immunosuppression caused by the virus. Herein, we demonstrate that the HBV-related antigen can be effectively inhibited and antiviral immunity can be successfully reactivated through codelivery of the small interfering RNA (siRNA) targeting HBV X protein (HBx) and the plasmid encoding interleukin 12 (pIL-12) to hepatocytes and immune cells. After being treated by the siRNA/pIL-12 codelivery system, HBx mRNA and hepatitis B surface antigen (HBsAg) are dramatically reduced in HepG2.215 cells. More importantly, the downregulated CD47 and programmed death ligand 1 (PD-L1) and the upregulated interferon-ß promoter stimulator-1 (IPS-1), retinoic acid-inducible gene-1 (RIG-1), CD80, and human leukocyte antigen-1 (HLA-1) in treated HepG2.215 cells indicate that the immunosuppression is reversed by the codelivery system. Furthermore, the codelivery system results in inhibition of extracellular regulated protein kinases (ERK) and phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt) pathways, as well as downregulation of B-cell lymphoma-2 (Bcl-2) and upregulation of p53, implying its potential in preventing the progression of HBV-induced HCC. In addition, J774A.1 macrophages treated by the codelivery system were successfully differentiated into the M1 phenotype and expressed enhanced cytokines with anti-hepatitis B effects such as interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α). Therefore, we believe that codelivery of siRNA and pIL-12 can effectively inhibit hepatitis B virus, reverse virus-induced immunosuppression, reactivate antiviral immunity, and hinder the progression of HBV-induced hepatocellular carcinoma. This investigation provides a promising approach for the synergistic treatment of HBV infection.

8.
Front Plant Sci ; 13: 878908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720552

RESUMO

Vegetation succession can change the function and quality of the soil. Exploring the changes in soil properties during secondary forest restoration is of great significance to promote forest restoration and improve the ecological service function of subtropical ecosystems in South China. In this study, we chose three typical forests in subtropical China as restoration sequences, broadleaf-conifer mixed forest (EF), broad-leaved forest (MF), and old-growth forest (LF), to study the changes in soil physico-chemical and biological properties and the changes of soil comprehensive quality during the secondary succession of subtropical forest. The results showed that the soil physical structure was optimized with the progress of forest succession. The soil bulk density decreased gradually with the progress of forest restoration, which was significantly affected by soil organic carbon (p < 0.01). In LF, the soil moisture increased significantly (p < 0.05), and its value can reach 47.85 ± 1.93%, which is consistent with the change of soil porosity. With the recovery process, soil nutrients gradually accumulated. Except for total phosphorus (TP), there was obvious surface enrichment of soil nutrients. Soil organic carbon (15.43 ± 2.28 g/kg), total nitrogen (1.08 ± 0.12 g/kg), and total phosphorus (0.43 ± 0.03 g/kg) in LF were significantly higher than those in EF (p < 0.05). The soil available nutrients, that is, soil available phosphorus and available potassium decreased significantly in LF (p < 0.05). In LF, more canopy interception weakened the P limitation caused by atmospheric acid deposition, so that the soil C:P (37.68 ± 4.76) and N:P (2.49 ± 0.24) in LF were significantly lower than those in EF (p < 0.05). Affected by TP and moisture, microbial biomass C and microbial biomass N increased significantly in LF, and the mean values were 830.34 ± 30.34 mg/kg and 46.60 ± 2.27 mg/kg, respectively. Further analysis showed that total soil porosity (TSP) and TP (weighted value of 0.61) contributed the most to the final soil quality index (SQI). With the forest restoration, the SQI gradually increased, especially in LF the value of SQI was up to 0.84, which was significantly higher than that in EF and MF (p < 0.05). This result is of great significance to understanding the process of restoration of subtropical forests and improving the management scheme of subtropical secondary forests.

9.
Chemosphere ; 263: 128007, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297040

RESUMO

Selenium is a trace element necessary for living organisms. It exists mainly in the form of selenite in nature. In plants, selenium can enhance defenses against pests. In this study, transcriptome sequencing technology was used to analyze the response mechanism of Tetranychus cinnabarinus to plant-mediated selenium treatment. We tested four sodium selenite treatments (5, 20, 50, and 200 µM) that were the same for short (2 d) and long (30 d) treatment durations. The results showed that the number of differentially expressed genes (DEGs) in the short-term treatment was greater than in the long-term treatment. This indicated that the gene expression of spider mites gradually stabilized during the selenium treatment. Regardless of the long-term and short-term conditions, spider mites had the largest response to the 20 µM sodium selenite treatment. The functional annotation classification of DEGs showed no significant difference under different concentrations and treatment durations. A total of 25 genes were differentially expressed in all eight treatments, including four down-regulated cytochrome P450 genes and one up-regulated chitinase gene. We speculate that selenium may have the potential to enhance the activity of chemical acaricides. Transcriptome sequencing of sodium selenite treatment at different concentrations and different times revealed the response mechanism of spider mites under plant-mediated selenium treatment. At the same time, it also provides new clues for the development of methods for preventing and controlling spider mites with selenium.


Assuntos
Acaricidas , Selênio , Tetranychidae , Animais , Sistema Enzimático do Citocromo P-450 , Selenito de Sódio , Tetranychidae/genética
10.
Nucleic Acids Res ; 41(19): 8803-21, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23907387

RESUMO

Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumor in adults. Decades of investigations and the recent effort of the Cancer Genome Atlas (TCGA) project have mapped many molecular alterations in GBM cells. Alterations on DNAs may dysregulate gene expressions and drive malignancy of tumors. It is thus important to uncover causal and statistical dependency between 'effector' molecular aberrations and 'target' gene expressions in GBMs. A rich collection of prior studies attempted to combine copy number variation (CNV) and mRNA expression data. However, systematic methods to integrate multiple types of cancer genomic data-gene mutations, single nucleotide polymorphisms, CNVs, DNA methylations, mRNA and microRNA expressions and clinical information-are relatively scarce. We proposed an algorithm to build 'association modules' linking effector molecular aberrations and target gene expressions and applied the module-finding algorithm to the integrated TCGA GBM data sets. The inferred association modules were validated by six tests using external information and datasets of central nervous system tumors: (i) indication of prognostic effects among patients; (ii) coherence of target gene expressions; (iii) retention of effector-target associations in external data sets; (iv) recurrence of effector molecular aberrations in GBM; (v) functional enrichment of target genes; and (vi) co-citations between effectors and targets. Modules associated with well-known molecular aberrations of GBM-such as chromosome 7 amplifications, chromosome 10 deletions, EGFR and NF1 mutations-passed the majority of the validation tests. Furthermore, several modules associated with less well-reported molecular aberrations-such as chromosome 11 CNVs, CD40, PLXNB1 and GSTM1 methylations, and mir-21 expressions-were also validated by external information. In particular, modules constituting trans-acting effects with chromosome 11 CNVs and cis-acting effects with chromosome 10 CNVs manifested strong negative and positive associations with survival times in brain tumors. By aligning the information of association modules with the established GBM subclasses based on transcription or methylation levels, we found each subclass possessed multiple concurrent molecular aberrations. Furthermore, the joint molecular characteristics derived from 16 association modules had prognostic power not explained away by the strong biomarker of CpG island methylator phenotypes. Functional and survival analyses indicated that immune/inflammatory responses and epithelial-mesenchymal transitions were among the most important determining processes of prognosis. Finally, we demonstrated that certain molecular aberrations uniquely recurred in GBM but were relatively rare in non-GBM glioma cells. These results justify the utility of an integrative analysis on cancer genomes and provide testable characterizations of driver aberration events in GBM.


Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Glioblastoma/genética , Algoritmos , Neoplasias Encefálicas/mortalidade , Deleção Cromossômica , Variações do Número de Cópias de DNA , Metilação de DNA , Transição Epitelial-Mesenquimal , Genes da Neurofibromatose 1 , Genoma Humano , Genômica/métodos , Glioblastoma/classificação , Glioblastoma/mortalidade , Humanos , MicroRNAs/metabolismo , Mutação , Prognóstico , Proteínas Celulares de Ligação ao Retinol/genética , Análise de Sobrevida , Transcrição Gênica
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(9): 2579-82, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23240443

RESUMO

Crystalline changes of different type starches after high hydrostatic pressure treated under 300, 450, 600 MPa were studied by X-ray diffraction. Waxy maize (A type, 100% amylopectin), hylon VII (B type, 30% amylopectin) and tapioca starch (C type, 83% amylopectin) were chosen. The results indicated that for waxy maize starch, annealing effect was observed at 300 MPa, disappearance of crystalline structure happened at 450 MPa and retrogradation at 600 MPa. The results proved that the granule under high hydrostatic pressure processing experiences "three development stages" including annealling effect, disappearance of crystalline structure and recrystalline after granule disintegration.


Assuntos
Amido/química , Difração de Raios X , Amilopectina , Pressão Hidrostática , Manihot , Zea mays
12.
Artigo em Inglês | MEDLINE | ID: mdl-19965258

RESUMO

Because of the rapid aging population in Taiwan and the trend of fewer children, people are looking into technical solutions for continuous/intermittent monitoring of vital signs in the home setting environment and the interactions between family members. In this study we developed a smart medical services system for managing chronic disease, called Citizen Telemedical Care service System (CTCS). The system integrates biosignal measurement, hypertension risk estimation expert system, clinic appointment service, video communication service, medical assistance referral, health frequency program record, and health/hygiene education. The demo version CTCS is exhibited in the center of INSIGHT opened for visit and trial use. In order to verify the demand and acceptability of the system and services, we have interviewed 251 volunteers with a questionnaire survey with the help from Taipei City Government. The results showed that people have positive expectation about the service program for health care and the capability of home devices. They also expressed high motivation on learning to use the system and to participate in the program. According to the evaluation results, the system is processing a small user test led by Taipei City Government, in order to further verify the acceptability and satisfaction of the system.


Assuntos
Diagnóstico por Computador/métodos , Monitorização Fisiológica/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Autocuidado/métodos , Autocuidado/estatística & dados numéricos , Telemedicina/métodos , Telemedicina/estatística & dados numéricos , Internet , Monitorização Fisiológica/métodos , Taiwan
13.
Artigo em Inglês | MEDLINE | ID: mdl-16245608

RESUMO

Focused interdigital transducers (FIDTs) can generate surface acoustic wave (SAW) with high intensity and high beamwidth compression ratio. Owing to these features, they are very suitable to be used as the sources of microacoustic channels or waveguides in the near future. The focusing properties of FIDTs are dominated solely by their geometric shapes. Therefore, to obtain optimal performance, it is essential to analyze the FIDTs with a variety of geometric shapes. However, among the existing studies concerning the diffraction of FIDTs, a detailed analysis and design of FIDTs is still in paucity. In this paper, we adopted the exact angular spectrum of plane wave theory (ASoW) to calculate the amplitude fields of FIDTs on Y-Z lithium niobate (LiNbO3) with the shape as a concentric circular arc and the concentric wave surface. Based on the calculation results, we discussed the variations of the amplitude fields induced by changing number of pairs, degree of arc, and geometric focal length. In addition, the focusing properties of FIDTs on the (100)-oriented GaAs substrate were also analyzed and discussed. We also summarized the guiderules for designing a FIDT via four important factors. It is worth noting that the results of this study provide an important basis for designing various FIDTs to fit the desired applications.

14.
J Huazhong Univ Sci Technolog Med Sci ; 22(2): 140-1, 147, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12658757

RESUMO

Twenty-seven in-patients with hemiplegia following brain injury were studied by using upper extremity median nerve somatosensory evoked patentials (SVEP), Brunnstrom assessment in hemiplegic hand and assessment of the patients' activities of daily lioing (ADL) (Barthel index). The upper extremity median nerve SEP on the affected and normal sides was determined. By using Kovindha standard, upper extremity median nerve SEP was graded in accordance with N20. The correlation between the differences of SEP N20 amplitude and the latencies on the both sides and the Barthel index scores was analyzed. A Spearman correlation analysis was made between the median nerve SEP N20 grades and Brunnstrom stages in hand or ADL on the affected side. The results showed that upper extremity median nerve SEP grades were positively correlated with those of the Brunnstrom stages in hand (r1 = 0.6925, P1 < 0.01). The correlation coefficient between SEP N20 grades and patients' ADL grades was r2 = 0.5015, P2 < 0.01. It was concluded that upper extremity median nerve SEP could be used as a sensitive electrophysiological predictor to clinically assess hemiplegic hand function. SEP N20 might play a role in predicting the ADL of the patients with hemiplegia to some extent, but could not be used as a sensitive predictor to directly observe and predict the ADL of the patients.


Assuntos
Infarto Cerebral/fisiopatologia , Potenciais Somatossensoriais Evocados , Hemiplegia/fisiopatologia , Nervo Mediano/fisiopatologia , Adulto , Idoso , Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Infarto Cerebral/complicações , Feminino , Hemiplegia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
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