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Messenger RNA (mRNA) vaccines are being used to combat the spread of COVID-19 (refs. 1-3), but they still exhibit critical limitations caused by mRNA instability and degradation, which are major obstacles for the storage, distribution and efficacy of the vaccine products4. Increasing secondary structure lengthens mRNA half-life, which, together with optimal codons, improves protein expression5. Therefore, a principled mRNA design algorithm must optimize both structural stability and codon usage. However, owing to synonymous codons, the mRNA design space is prohibitively large-for example, there are around 2.4 × 10632 candidate mRNA sequences for the SARS-CoV-2 spike protein. This poses insurmountable computational challenges. Here we provide a simple and unexpected solution using the classical concept of lattice parsing in computational linguistics, where finding the optimal mRNA sequence is analogous to identifying the most likely sentence among similar-sounding alternatives6. Our algorithm LinearDesign finds an optimal mRNA design for the spike protein in just 11 minutes, and can concurrently optimize stability and codon usage. LinearDesign substantially improves mRNA half-life and protein expression, and profoundly increases antibody titre by up to 128 times in mice compared to the codon-optimization benchmark on mRNA vaccines for COVID-19 and varicella-zoster virus. This result reveals the great potential of principled mRNA design and enables the exploration of previously unreachable but highly stable and efficient designs. Our work is a timely tool for vaccines and other mRNA-based medicines encoding therapeutic proteins such as monoclonal antibodies and anti-cancer drugs7,8.
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Algoritmos , Vacinas contra COVID-19 , COVID-19 , Estabilidade de RNA , RNA Mensageiro , SARS-CoV-2 , Vacinas de mRNA , Animais , Humanos , Camundongos , Códon/genética , COVID-19/genética , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/química , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/imunologia , Meia-Vida , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/imunologia , Vacinas de mRNA/química , Vacinas de mRNA/genética , Vacinas de mRNA/imunologia , Estabilidade de RNA/genética , Estabilidade de RNA/imunologia , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/imunologia , RNA Mensageiro/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/imunologiaRESUMO
Developing functional medical materials is urgent to treat diabetic wounds with a high risk of bacterial infections, high glucose levels and oxidative stress. Here, a smart copper-based nanocomposite acidic spray has been specifically designed to address this challenge. This copper-based nanocomposite is pH-responsive and has multienzyme-like properties. It enables the spray to effectively eliminate bacteria and alleviate tissue oxidative pressure, thereby accelerating the healing of infected diabetic wounds. The spray works by generating hydroxyl radicals through catalysing H2O2, which has a high sterilization efficiency of 97.1%. As alkaline micro-vessel leakage neutralizes the acidic spray, this copper-based nanocomposite modifies its enzyme-like activity to eliminate radicals. This reduces the level of reactive oxygen species in diabetic wounds by 45.3%, leading to a similar wound-healing effect between M1 diabetic mice and non-diabetic ones by day 8. This smart nanocomposite spray provides a responsive and regulated microenvironment for treating infected diabetic wounds. It also offers a convenient and novel approach to address the challenges associated with diabetic wound healing.
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Cobre , Diabetes Mellitus Experimental , Polifenóis , Cicatrização , Cicatrização/efeitos dos fármacos , Cobre/química , Cobre/farmacologia , Animais , Camundongos , Polifenóis/farmacologia , Polifenóis/química , Nanocompostos/química , Infecções Bacterianas/tratamento farmacológico , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismoRESUMO
Excess fluoride ions in groundwater accumulate through the roots of crops, affecting photosynthesis and inhibiting their growth. Long-term bioaccumulation also threatens human health because it is poorly degradable and toxic. Currently, one of the biggest challenges is developing a unique material that can efficiently remove fluoride ions from the environment. The excellent properties of functionalized pillar[5]arene polymer-filled nanochannel membranes were explored to address this challenge. Constructing a multistage porous nanochannel membrane, consisting of microscale etched nanochannels and nanoscale pillar[5]arene cross-linked polymer voids. A fluoride removal rate of 0.0088â mmol â L-1 â min-1 was achieved. Notably, this rate surpassed the rates observed with other control ions by a factor of 6 to 8.8. Our research provides a new direction for developing water fluoride ion removal materials.
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OBJECTIVES: To analyze the factors affecting the concentrations of the active moiety of risperidone (RIS) and its active metabolite 9-hydroxyrisperidone (9-OH-RIS) in psychiatric outpatients taking immediate-release formulations. METHODS: This is a retrospective study on the therapeutic drug monitoring (TDM) data regarding RIS and 9-OH-RIS in adult psychiatric outpatients. TDM data with simultaneous RIS and 9-OH-RIS monitoring from March 2018 to February 2020 and relevant medical records (including dosage, dosage form, sex, age, diagnosis, combined medication, and comorbid disease) from 399 adult psychiatric outpatients (223 males and 176 females) were included in this study. RESULTS: The daily dose of RIS was 5.56 ± 2.05 mg, the concentration of total active moiety was 42.35 ± 25.46 ng/mL, and the dose-adjusted plasma concentration (C/D) of active moiety was 7.83 ± 3.87 (ng/ml)/(mg/day). Dose, sex, and age were identified as important factors influencing concentrations of RIS and 9-OH-RIS in adult psychiatric outpatients. CONCLUSIONS: Individualized medication adjustments should be made according to the specific conditions of psychiatric outpatients. The findings strongly support the use of TDM to guide dosing decisions in psychiatric outpatients taking RIS.
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Antipsicóticos , Risperidona , Adulto , Masculino , Feminino , Humanos , Risperidona/uso terapêutico , Palmitato de Paliperidona/efeitos adversos , Antipsicóticos/efeitos adversos , Estudos Retrospectivos , Pacientes AmbulatoriaisRESUMO
Knowledge on population structure and genetic diversity is a focal point for association mapping studies and genomic selection. Genotyping by sequencing (GBS) represents an innovative method for large scale SNP detection and genotyping of genetic resources. Here we used the GBS approach for the genome-wide identification of SNPs in a collection of Cynoglossus semilaevis and for the assessment of the level of genetic diversity in C. semilaevis genotypes. GBS analysis generated a total of 55.12 Gb high-quality sequence data, with an average of 0.63 Gb per sample. The total number of SNP markers was 563, 109. In order to explore the genetic diversity of C. semilaevis and to select a minimal core set representing most of the total genetic variation with minimum redundancy, C. semilaevis sequences were analyzed using high quality SNPs. Based on hierarchical clustering, it was possible to divide the collection into 2 clusters. The marine fishing populations were clustered and clearly separated from the cultured populations, and the cultured populations from Hebei was also distinct from the other two local populations. These analyses showed that genotypes were clustered based on species-related features. Differential significant SNPs were also captured and validated by GBS and SNaPshot, with linkage disequilibrium and haplotype analysis, seven SNPs have been confirmed to have obvious differentiation in two populations, which may be used as the characteristic evaluation sites of sea-captured and cultured Cynoglossus semilaevis populations. And SNP markers and information on population structure developed in this study will undoubtedly support genome-wide association mapping studies and marker-assisted selection programs. These differential SNPs could be also employed as the characteristic evaluation sites of sea-captured and cultured Cynoglossus semilaevis populations in future.
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Linguados/genética , Polimorfismo de Nucleotídeo Único , Animais , Cromossomos , Frequência do Gene , Haplótipos , Desequilíbrio de Ligação , Oceanos e MaresRESUMO
Neuropathic pain (NP) is a clinically incurable disease with miscellaneous causes, complicated mechanisms and available therapies show poor curative effect. Some recent studies have indicated that neuroinflammation plays a vital role in the occurrence and promotion of NP and anti-inflammatory therapy has the potential to relieve the pain. During the past decades, mesenchymal stem cells (MSCs) with properties of multipotentiality, low immunogenicity and anti-inflammatory activity have showed excellent therapeutic effects in cell therapy from animal models to clinical application, thus aroused great attention. However there are no reports about the effect of intrathecal human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) on NP which is induced by peripheral nerve injury. Therefore, in this study, intrathecally transplanted HUC-MSCs were utilized to examine the effect on neuropathic pain induced by a rat model with spinal nerve ligation (SNL), so as to explore the possible mechanism of those effects. As shown in the results, the HUC-MSCs transplantation obviously ameliorated SNL-induced mechanical allodynia and thermal hyperalgesia, which was related to the inhibiting process of neuroinflammation, including the suppression of activated astrocytes and microglia, as well as the significant reduction of pro-inflammatory cytokines Interleukin-1ß (IL-1ß) and Interleukin -17A (IL-17A) and the up-regulation of anti-inflammatory cytokine Interleukin -10 (IL-10). Therefore, through the effect on glial cells, pro-inflammatory and anti-inflammatory cytokine, the targeting intrathecal HUC-MSCs may offer a novel treatment strategy for NP.
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Transplante de Células-Tronco Mesenquimais , Neuralgia/terapia , Cordão Umbilical/citologia , Animais , Astrócitos/metabolismo , Humanos , Hiperalgesia/etiologia , Hiperalgesia/fisiopatologia , Hiperalgesia/terapia , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/terapia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Ligadura , Masculino , Microglia/metabolismo , Neuralgia/etiologia , Neuralgia/fisiopatologia , Ratos Sprague-Dawley , Nervos Espinhais/lesõesRESUMO
Optimizing the antibacterial effectiveness of copper ions while reducing environmental and cellular toxicity is essential for public health. A copper chelate, named PAI-Cu, is skillfully created using a specially designed carboxyl copolymer (a combination of acrylic and itaconic acids) with copper ions. PAI-Cu demonstrates a broad-spectrum antibacterial capability both in vitro and in vivo, without causing obvious cytotoxic effects. When compared to free copper ions, PAI-Cu displays markedly enhanced antibacterial potency, being about 35 times more effective against Escherichia coli and 16 times more effective against Staphylococcus aureus. Moreover, Gaussian and ab initio molecular dynamics (AIMD) analyses reveal that Cu+ ions can remain stable in the carboxyl compound's aqueous environment. Thus, the superior antibacterial performance of PAI-Cu largely stems from its modulation of copper ions between mono- and divalent states within the Cu-carboxyl chelates, especially via the carboxyl ligand. This modulation leads to the generation of reactive oxygen species (ËOH), which is pivotal in bacterial eradication. This research offers a cost-effective strategy for amplifying the antibacterial properties of Cu ions, paving new paths for utilizing copper ions in advanced antibacterial applications.
Assuntos
Antibacterianos , Quelantes , Cobre , Escherichia coli , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Cobre/química , Cobre/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Escherichia coli/efeitos dos fármacos , Quelantes/química , Quelantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Estrutura MolecularRESUMO
OBJECTIVE: Gastric cancer (GC) has become a significant contributor globally to cancer-related mortalities. Accordingly, there is a critical need to identify a new therapeutic target for GC. Recently, the hexokinase domain containing 1 (HKDC1), an oncogenic factor, has been recognized in various cancers. Nevertheless, the role of HKDC1 in GC still needs to be explored. This study is aimed to investigate the role of HKDC1 in GC. METHODS: Initially, the HKDC1 expression in GC tissue samples and cell lines was analyzed using RT-qPCR, exploring its correlation with overall patient survival. Further, short hairpin RNA (shRNA) technology was employed to establish HKDC1 knockdown in GC cell lines and assess the impact of HKDC1 deficiency on tumor growth in vitro and in vivo. RESULTS: RT-qPCR results revealed overexpression of HKDC1 in GC tissue samples and cell lines, which could be correlated to shorter patient survival. HKDC1 knockdown led to decreased viability and colony formation ability of GC cells. Moreover, the transwell assay demonstrated that downregulating HKDC1 significantly suppressed the migration and invasion abilities of GC cells. Eventually, the xenograft tumor model derived from HKDC1 knockdown GC cells in mice exhibited reduced tumor size and deprived Ki67 expression, indicating inhibited tumor growth. CONCLUSION: The study provided evidence of HKDC1 dysregulation in GC tissues, suggesting its potential as a promising novel target for GC treatment.
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Neoplasias Gástricas , Animais , Humanos , Camundongos , Biomarcadores , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Hexoquinase/genética , Hexoquinase/metabolismo , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismoRESUMO
In human and rodents, some individuals may remain lean even when they are challenged with high calorie intake. Here, we used C57BL/6J mice to establish animal models of high-fat diet (HFD) induced obesity sensitive (DIO) mice and obesity resistant (DIR) mice. In DIR mice, improved metabolic profile through brown adipose tissue (BAT) activation was observed, while plasma unconjugated bile acids (BAs) were decreased together with increased intestine tauro-conjugated BAs (e.g., T-ß-MCA). The composition of the gut flora also differs greatly between DIR and DOR. Using fecal microbiota transplants from DIR mice, HFD fed recipient mice exhibited a trend toward reduced adiposity and improved glucose tolerance, showing increased serum tauro-conjugated BAs levels. STC-1 cell experiments confirmed T-ß-MCA could activate FXR/TGR5 pathway and induce the production of GLP-1, inhibiting genes that regulate the ceramide synthesis. Our results indicated that the DIR mice exhibited higher energy expenditure by activating BAT thermogenesis, which may be related to altered gut microbiota-bile acids-glucagon like peptide-1 axis.
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Ácidos e Sais Biliares , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Camundongos Endogâmicos C57BL , Obesidade/metabolismoRESUMO
Protein transport is an interesting and intrinsic life feature that is highly relevant to physiology and disease in living beings. Herein, inspired by nature, based on the supramolecular host-guest interaction, we have introduced the classical azobenzene light switches and L-phenylalanine derived pillar[6]arene (L-Phe-P6) into the artificial nanochannel to construct light-responsive nanochannels that could regulate protein transport effectively under the control of ultraviolet (UV) and visible (Vis) light. The light-controlled distribution of L-Phe-P6 in the channel led to the difference in surface charges in the nanochannel, which eventually brought the difference in protein transport. This research may not only provide a convenient theoretical model for biological research, but also a flexible light-responsive protein transport model, which will play a crucial role in light-controlled release of protein drugs and so on.
Assuntos
Compostos de Amônio Quaternário , Raios Ultravioleta , Luz , Transporte ProteicoRESUMO
Type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) share several common pathophysiological features. Rare variants of triggering receptor expressed on myeloid cells 2 (TREM2) increase the risk of developing AD, suggesting the involvement of TREM2 and innate immunity in AD development. It is still unknown whether TREM2 is related to cognitive impairment in T2DM. Here, we investigated the effects of the hippocampal overexpression of TREM2 on cognitive in long-term high-fat diet (HFD)-fed mice. Male C57BL/6J mice were maintained on HFD for 50 weeks. TREM2 was overexpressed in the hippocampus 36 weeks after HFD feeding using adeno-associated virus vector (AAV)-mediated gene delivery. The results showed that the HFD feeding induced rapid and persistent weight gain, glucose intolerance and significant impairments in learning and memory. Compared with AAV-con, AAV-TREM2 significantly ameliorated cognitive impairment without altering body weight and glucose homeostasis in HFD mice. The overexpression of TREM2 upregulated the synaptic proteins spinophilin, PSD95 and synaptophysin, suggesting the improvement in synaptic transmission. Dendritic complexity and spine density in the CA1 region were rescued after TREM2 overexpression. Furthermore, TREM2 markedly increased the number of iba-1/Arg-1-positive microglia in the hippocampus, suppressed neuroinflammation and microglial activation. In sum, hippocampal TREM2 plays an important role in improving HFD-induced cognitive dysfunction and promoting microglial polarization towards the M2 anti-inflammatory phenotype. Our study also suggests that TREM2 might be a novel target for the intervention of obesity/diabetes-associated cognitive decline.
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OBJECTIVE: To explore the effects of taurolithocholic acid (tLCA) and chenodeoxycholic acid (CDCA) on the expression of aorexigenic neuropeptide in mouse hypothalamus GT1-7 cells. METHODS: Mouse hypothalamic GT1-7 cells were treated with culture medium containing 10% FBS (control group, n=3) or with 10 nmol/L, 100 nmol/L, 1 µmol/L and 10 µmol/L tLCA (tLCA group, n=3) or CDCA (CDCA group, n=3) for 12, 24 or 48 h. Real-time PCR was performed to determine the expression levels of proopiomelanocortin (POMC) mRNA in the cells, and the production levels of α-melanocyte-stimulating hormone (α-MSH) were assessed using an ELISA kit. Signal transduction and activator of transcription 3 phosphorylation (p-STAT3), threonine kinase phosphorylation (p-AKT), suppressor of cytokine signaling 3 (SOCS3), G protein-coupled bile acid receptor-1 (TGR5) and farnesoid X receptor (FXR) protein were detected by Western blotting. RESULTS: Western blotting results showed that mouse hypothalamic GT1-7 cells expressed two bile acid receptors, TGR5 and FXR, whose expressions were regulated by bile acids. Real-time PCR showed that the expression of POMC mRNA was significantly increased in the cells after treatment with 10 µmol/L tLCA or CDCA for 24 h. POMC-derived anorexigenic peptide α-MSH increased significantly in GT1-7 cells after treatment with 10 µmol/L tLCA or CDCA for 24 h. Treatment of the cells with tLCA or CDCA significantly increased the expressions of intracellular signaling proteins including p-STAT3, p-AKT and SOCS3. CONCLUSIONS: Mouse hypothalamic GT1-7 cells express bile acid receptors TGR5 and FXR. Bile acids tLCA or CDCA can promote the expression of POMC mRNA and increase the production of the anorexigenic peptide α-MSH. The intracellular signaling proteins p-AKT, p-STAT3 and SOCS3 are likely involved in bile acid-induced anorexigenic peptide production.
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Transdução de Sinais , Animais , Ácidos e Sais Biliares , Ácido Quenodesoxicólico , Hipotálamo , Camundongos , Neuropeptídeos , Fosforilação , Fator de Transcrição STAT3 , Proteína 3 Supressora da Sinalização de CitocinasRESUMO
Strong early vigour plays a crucial role in wheat yield improvement by enhancing resource utilization efficiency. Synthetic hexaploid wheat (SHW) combines the elite genes of tetraploid wheat with Aegilops tauschii and has been widely used in wheat genetic improvement for its abundant genetic variation. The two SHWs Syn79 and Syn80 were derived from the crossing of the same tetraploid wheat DOY1 with two different Ae. tauschii accessions, AT333 and AT428, respectively. The Syn80 possessed better early vigour traits than Syn79, theretically caused by their D genome from Ae. tauschii. To dissect their genetic basis in a hexaploid background, 203 recombinant inbred lines (RILs) derived from the cross of Syn79 x Syn80 were developed to detect quantitative trait loci (QTL) for four early biomass related traits: plant height (PH), tiller number (TN), shoot fresh weight (SFW) and shoot dry weight (SDW) per plant, under five different environmental conditions. Determined from the data of SNP markers, two genome regions on 1DS and 7D were stably associated with the four early biomass related traits showing pleiotropic effects. Four stable QTLs QPh.saas-1DS, QTn.saas-1DS, QSfw.saas-1DS and QSdw.saas-1DS explaining 7.92, 15.34, 9.64 and 10.15% of the phenotypic variation, respectively, were clustered in the region of 1DS from AX-94812958 to AX-110910133. Meanwhile, QPh.saas-7D, QTn.saas-7D, QSfw.saas-7D and QSdw.saas-7D were flanked by AX-109917900 and AX-110605376 on 7D, explaining 16.12, 24.35, 15.25 and 13.37% of the phenotypic variation on average, respectively. Moreover, these genomic QTLs on 1DS and 7D enhancing biomass in the parent Syn80 were from Ae. tauschii AT428. These findings suggest that these two QTLs from Ae. tauschii can be expressed stably in a hexaploid background at the jointing stage and be used for wheat improvement.
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Aegilops/genética , Mapeamento Cromossômico , Genoma de Planta , Locos de Características Quantitativas , Triticum/genética , Biomassa , Produção Agrícola , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Poliploidia , Triticum/crescimento & desenvolvimentoRESUMO
Maintaining stabilization of the intestinal microbiota is important in preventing bacterial diseases in cultured fish. At present, there have been no reports on the composition and functional analysis of intestinal microbiota in Yunlong Grouper (Epinephelus moaraâ × Epinephelus lanceolatusâ). In this study we analyzed and compared the intestinal microbiota composition of healthy and diseased pond-reared fish to discern the functional profile of a healthy status. The richness and diversity of the intestinal microbiota did not differ significantly between diseased and healthy fish, yet the abundance of predominant phyla like the Proteobacteria were upregulated in the diseased Yunlong Grouper. At the genus level, a significant reduction of Cetobacterium was observed in the intestinal tracts of diseased fish, as Pseudomonas became the most dominant bacterium. To compare the intestinal microorganism abundances between the two health groups of fish, we first screened the gut bacteria and discerned 4 phyla and 12 genera to designate a healthy status in Yunlong Grouper. The environmental bacterial community influenced composition of the intestinal microbiota in Yunlong Grouper, and the intestinal microbiota of diseased fish was more susceptible to the influence of the culture water. In addition, the prediction of functional genes by phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) indicated that the intestinal microbiota of Yunlong Grouper is related mainly to the terms "metabolism, environmental information processing, genetic information processing, human diseases, and cellular processing; moreover, the functions of the intestinal microbiota differed between the different health states of this fish. The overall results indicate that the occurrence of disease can affect the composition and function of the intestinal microbiota in a cultured fish.
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Pulmonary fibrosis is an aggressive endstage disease. Transforming growth factorß1 (TGFß1) mediates lung ï¬broblast activation and is essential for the progress of pulmonary fibrosis. BML111, a lipoxinA4 (LXA4) receptor (ALX) agonist, has been reported to possess antiï¬brotic properties. The present study aimed to elucidate whether BML111 inhibits TGFß1induced mouse embryo lung ï¬broblast (NIH3T3 cell line) activation in vitro and bleomycin (BLM)induced pulmonary fibrosis in vivo. In vitro experiments demonstrated that BML111 treatment inhibits TGFß1induced NIH3T3 cell viability and the expression of smooth muscle α actin (αSMA), ï¬bronectin and total collagen. Furthermore, this suppressive effect was associated with mothers against decapentaplegic homolog (Smad)2/3, extracellular signalregulated kinase (ERK) and Akt phosphorylation interference. In vivo experiments revealed that BML111 treatment markedly improved survival rate and ameliorated the destruction of lung tissue structure. It also reduced interleukin1ß (IL1ß), tumor necrosis factorα (TNFα) and TGFß1 expression in the BLM intratracheal mouse model. In addition, the expression ofαSMA and extracellular matrix (ECM) deposition (total collagen, hydroxyproline and ï¬bronectin) were also suppressed following BML111 treatment. However, BOC2, an antagonist of ALX, partially weakened the effects of BML111. In conclusion, these results indicated that BML111 inhibits TGFß1induced ï¬broblasts activation and alleviates BLMinduced pulmonary fibrosis. Therefore, BML111 may be used as a potential therapeutic agent for pulmonary fibrosis treatment.
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Fibroblastos/metabolismo , Ácidos Heptanoicos/farmacologia , Fibrose Pulmonar/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Masculino , Camundongos , Células NIH 3T3 , Prognóstico , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Resultado do TratamentoRESUMO
A new cellulolytic strain of Chryseobacterium genus was screened from the dung of a cattle fed with cereal straw. A putative cellulase gene (cbGH5) belonging to glycoside hydrolase family 5 subfamily 46 (GH5_46) was identified and cloned by degenerate PCR plus genome walking. The CbGH5 protein was overexpressed in Pichia pastoris, purified and characterized. It is the first bifunctional cellulase-xylanase reported in GH5_46 as well as in Chryseobacterium genus. The enzyme showed an endoglucanase activity on carboxymethylcellulose of 3237 µmol min-1 mg-1 at pH 9, 90 °C and a xylanase activity on birchwood xylan of 1793 µmol min-1 mg-1 at pH 8, 90 °C. The activity level and thermophilicity are in the front rank of all the known cellulases and xylanases. Core hydrophobicity had a positive effect on the thermophilicity of this enzyme. When similar quantity of enzymatic activity units was applied on the straws of wheat, rice, corn and oilseed rape, CbGH5 could obtain 3.5-5.0× glucose and 1.2-1.8× xylose than a mixed commercial cellulase plus xylanase of Novozymes. When applied on spent mushroom substrates made from the four straws, CbGH5 could obtain 9.2-15.7× glucose and 3.5-4.3× xylose than the mixed Novozymes cellulase+xylanase. The results suggest that CbGH5 could be a promising candidate for industrial lignocellulosic biomass conversion.
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Celulase/isolamento & purificação , Celulase/metabolismo , Chryseobacterium/enzimologia , Chryseobacterium/isolamento & purificação , Fezes/microbiologia , Xilosidases/isolamento & purificação , Xilosidases/metabolismo , Animais , Biotransformação , Carboximetilcelulose Sódica/metabolismo , Bovinos , Celulase/genética , Chryseobacterium/genética , Clonagem Molecular , Glucose/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Pichia/genética , Pichia/metabolismo , Caules de Planta/metabolismo , Reação em Cadeia da Polimerase , Xilosidases/genéticaRESUMO
A cascade reaction combining the enzymatic hydrolysis of Penicillin G potassium salt (PGK) with the kinetically controlled enzymatic coupling of in situ formed 6-aminopenicillanic acid (6-APA) with p-hydroxyphenylglycine methyl ester (D-HPGM) to give amoxicillin as the final product by using a single enzyme has been demonstrated successfully. Ethylene glycol (EG) was employed as a component of reaction buffer to improve the synthesis yield. Reaction parameters, including different cosolvents, EG content, the loading of immobilized penicillin G acylase (IPA), and reaction temperature and time were studied to evaluate their effects on the reaction. The best result of 55.2% yield was obtained from the reaction which was carried out in the mixed media containing 40% sodium dihydrogen phosphate buffer (apparent pH 6.0) and 60% EG (v/v), with the initial concentration 150 mM and 450 mM of PGK and D-HPGM, respectively, catalyzed by 50 IU/mL IPA at 25 degrees C for 10 h. The IPA could be recycled for nine batches without obviously losing of catalytic activity. The important strategy will have potential application in the beta-lactam antibiotics industry due to the advantages of saving the effort of isolating 6-APA, reducing usual enzymatic steps and the industrial cost of amoxicillin synthesis.