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1.
Nano Lett ; 23(8): 3298-3308, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37070785

RESUMO

Intracellular bacteria are the major contributor to the intractability of septic arthritis, which are sequestered in macrophages to undermine the innate immune response and avoid the antibacterial effect of antibiotics due to the obstruction of the cell membrane. Herein, we report a thermoresponsive nanoparticle, which consists of a phase-change material shell (fatty acids) and an oxygen-producing core (CaO2-vancomycin). Under external thermal stimulation, the shell of the nanoparticle transforms from a solid phase to a liquid phase. Then the CaO2-Vancomycin core is exposed to the surrounding aqueous solution to release vancomycin and generate Ca(OH)2 and oxygen, thereby depleting accumulated lactate to mitigate lactate-associated immunosuppression, stabilizing hypoxia-inducible factor-1α (HIF-1α) to enhance M1-like polarization of macrophages, and increasing reactive oxygen species (ROS) and reactive nitrogen species (RNS) production. This combined effect between the controlled release of antibiotics and enhancement of host innate immunity provides a promising strategy to combat intracellular bacteria for septic arthritis therapy.


Assuntos
Artrite Infecciosa , Nanopartículas , Humanos , Ácido Láctico , Vancomicina , Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Terapia de Imunossupressão , Artrite Infecciosa/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/metabolismo
2.
Int J Mol Sci ; 25(18)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39337570

RESUMO

Short-chain dehydrogenase/reductases (SDRs) are the largest NAD(H)-dependent oxidoreductase superfamilies and are involved in diverse metabolisms. This study presents a comprehensive genomic analysis of the SDR superfamily in Cinnamomum camphora, a species that is one of the most significant woody essential oil plants in southern China. We identify a total of 222 CcSDR proteins and classify them into five types based on their cofactor-binding and active sites: 'atypical', 'classic', 'divergent', 'extended', and 'unknown'. Phylogenetic analysis reveals three evolutionary branches within the CcSDR proteins, and further categorization using the SDR-initiative Hidden Markov model resulted in 46 families, with the CcSDR110C, CcSDR108E, and CcSDR460A families being the most populous. Collinearity analysis identified 34 pairs of CcSDR paralogs in C. camphora, 141 pairs of SDR orthologs between C. camphora and Populus trichocarpa, and 59 pairs between C. camphora and Oryza sativa. Expression profile analysis indicates a preference for the expression of 77 CcSDR genes in specific organs such as flowers, bark, twigs, roots, leaves, or fruits. Moreover, 77 genes exhibit differential expression patterns during the four developmental stages of leaves, while 130 genes show variance across the five developmental stages of fruits. Additionally, to explore the biosynthetic mechanism of methyl eugenol, a key component of the leaf essential oil in the methyl eugenol chemotype, this study also identifies eugenol synthase (EGS) within the CcSDR460A family through an integrated strategy. Real-time quantitative PCR analysis demonstrates that the expression of CcEGS in the leaves of the methyl eugenol chemotype is more than fourfold higher compared to other chemotypes. When heterologously expressed in Escherichia coli, it catalyzes the conversion of coniferyl acetate into a mixture predominantly composed of eugenol (71.44%) and isoeugenol (21.35%). These insights pave the way for future research into the functional diversity of CcSDR genes, with a focus on secondary metabolism.


Assuntos
Cinnamomum camphora , Eugenol , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas , Cinnamomum camphora/genética , Cinnamomum camphora/metabolismo , Eugenol/análogos & derivados , Eugenol/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Estudo de Associação Genômica Ampla
3.
Sensors (Basel) ; 23(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36772395

RESUMO

Speech reflects people's mental state and using a microphone sensor is a potential method for human-computer interaction. Speech recognition using this sensor is conducive to the diagnosis of mental illnesses. The gender difference of speakers affects the process of speech emotion recognition based on specific acoustic features, resulting in the decline of emotion recognition accuracy. Therefore, we believe that the accuracy of speech emotion recognition can be effectively improved by selecting different features of speech for emotion recognition based on the speech representations of different genders. In this paper, we propose a speech emotion recognition method based on gender classification. First, we use MLP to classify the original speech by gender. Second, based on the different acoustic features of male and female speech, we analyze the influence weights of multiple speech emotion features in male and female speech, and establish the optimal feature sets for male and female emotion recognition, respectively. Finally, we train and test CNN and BiLSTM, respectively, by using the male and the female speech emotion feature sets. The results show that the proposed emotion recognition models have an advantage in terms of average recognition accuracy compared with gender-mixed recognition models.


Assuntos
Aprendizado Profundo , Humanos , Masculino , Feminino , Fala , Emoções , Acústica
4.
Molecules ; 28(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37175069

RESUMO

Cinnamomum plants are rich in natural essential oils, which are widely used as materials in the fragrance, insecticidal, antibacterial agent, pharmaceutical, and food industries; however, few studies have investigated the essential oil components of Cinnamomum bodinieri. Therefore, this study investigated the diversity of essential oils from the leaves of 885 individual C. bodinieri plants across 32 populations in five provinces. Essential oils were extracted by hydrodistillation, and then qualitative and quantitative analyses of the compounds were performed by GC-MS and GC-FID. A total of 87 chemical constituents were identified in the essential oils, including 33 monoterpenes, 48 sesquiterpenes, and six other compounds. The average oil yield was 0.75%, and individual oil yields ranged from 0.01% to 4.28%. A total of 16 chemotypes were classified according to variations in the essential oil chemical constituents of C. bodinieri, among which the camphor-type, citral-type, and eucalyptol-type were dominant. Moreover, the borneol-type, cymol-type, elemol-type, methylisoeugenol-type, and selina-6-en-4-ol-type were reported in C. bodinieri for the first time. The yield and principal components of the essential oils were mainly affected by altitude, temperature, and sunshine duration, among which altitude had the most significant effect; thus, low-altitude areas are more suitable for the synthesis and accumulation of essential oils. Based on the different characteristics of the essential oils in the leaves of C. bodinieri, several excellent populations and individuals were identified in this study. Moreover, the findings provide a foundation for breeding superior varieties and studying essential oil biosynthesis mechanisms in the future.


Assuntos
Cinnamomum , Óleos Voláteis , Humanos , Óleos Voláteis/química , Cinnamomum/química , Melhoramento Vegetal , Monoterpenos/química , Folhas de Planta/química
5.
World J Microbiol Biotechnol ; 39(7): 191, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37160824

RESUMO

α-L-rhamnosidase [EC 3.2.1.40] belongs to glycoside hydrolase (GH) families (GH13, GH78, and GH106 families) in the carbohydrate-active enzymes (CAZy) database, which specifically hydrolyzes the non-reducing end of α-L-rhamnose. Αccording to the sites of catalytic hydrolysis, α-L-rhamnosidase can be divided into α-1, 2-rhamnosidase, α-1, 3-rhamnosidase, α-1, 4-rhamnosidase and α-1, 6-rhamnosidase. α-L-rhamnosidase is an important enzyme for various biotechnological applications, especially in food, beverage, and pharmaceutical industries. α-L-rhamnosidase has a wide range of sources and is commonly found in animals, plants, and microorganisms, and its microbial source includes a variety of bacteria, molds and yeasts (such as Lactobacillus sp., Aspergillus sp., Pichia angusta and Saccharomyces cerevisiae). In recent years, a series of advances have been achieved in various aspects of α-validates the above-described-rhamnosidase research. A number of α-L-rhamnosidases have been successfully recombinant expressed in prokaryotic systems as well as eukaryotic systems which involve Pichia pastoris, Saccharomyces cerevisiae and Aspergillus niger, and the catalytic properties of the recombinant enzymes have been improved by enzyme modification techniques. In this review, the sources and production methods, general and catalytic properties and biotechnological applications of α-L-rhamnosidase in different fields are summarized and discussed, concluding with the directions for further in-depth research on α-L-rhamnosidase.


Assuntos
Biocatálise , Biotecnologia , Indústria Farmacêutica , Indústria Alimentícia , Glicosídeo Hidrolases , Microbiologia Industrial , Animais , Humanos , Glicosídeo Hidrolases/biossíntese , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
6.
J Transl Med ; 20(1): 12, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34980148

RESUMO

BACKGROUND: The status of vaginal microbiota in persistent high-risk human papilloma virus (HR-HPV) infection is unclear. The present work aimed to identify the vaginal microbiota of persistent HPV infection and explore the possible underlying microbiota factors. METHODS: A total of 100 women were recruited in this study, of which 28 presented HR-HPV persistent infection (P group), 30 showed clearance of any subtype of HR-HPV (C group), and 42 had no history of any HR-HPV infection (NC group). The vaginal microbiota and the community structure of the three groups were compared based on the 16S rRNA sequencing of the V3-V4 region. The microbiota diversity and differential analysis were carried out to detect the potential factors associated with HR-HPV infection. RESULTS: P and C groups showed an increase of Firmicutes and Actinobacteriota but a decrease in Proteobacteria compared to the NC group. The Chao1 index indicated that the microbial richness of the NC group was greater than C group (P < 0.05).The principal co-ordinate analysis(PCoA) revealed differences between the NC and P/C groups.The linear discriminant analysis effect size (LEfSe) method indicated that Proteobacteria phylum was significantly different in the mean relative abundance in the NC group,but the P and C groups did not show such indicative taxa. The Wilcox rank-sum test indicated that the Bifidobacterium (P = 0.002) and Lactobacillus (P = 0.005) of the C group were in a high mean relative abundance compared to the NC group. CONCLUSIONS: The persistent HR-HPV infection is associated with dysbiosis of the vaginal microbiota. Microbiome regulation with Bifidobacteria and Lactobacillus may affect the clearance of HPV.


Assuntos
Microbiota , Infecções por Papillomavirus , Disbiose , Feminino , Humanos , Papillomaviridae , RNA Ribossômico 16S/genética , Vagina/microbiologia
7.
Exp Cell Res ; 406(1): 112755, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332981

RESUMO

Liver cancer is one of the most common and high recurrence malignancies. Besides radiotherapy and surgery, chemotherapy also plays an essential role in the treatment of liver cancer. Sorafenib and sorafenib-based combination therapies have been proven efficacy against tumors. However, previous clinical studies have indicated that some patients with liver cancer are resistant to sorafenib treatment and the existing strategies are not satisfactory in the clinic. Therefore, it is urgent to investigate strategies to improve the effectiveness of sorafenib for liver cancer and to explore effective drug combinations. In the present study, we found that dichloroacetate (DCA) could significantly enhance the anti-tumor effect of sorafenib on liver cancer cells, including reduced viability and dramatically promoted apoptosis in liver cancer cells. Moreover, compared to sorafenib alone, the combination of DCA and sorafenib markedly increased the degradation of anti-apoptotic protein Mcl-1 by enhancing its phosphorylation. Overexpression of Mcl-1 could significantly attenuate the synergetic effect of DCA and sorafenib on apoptosis induction in liver cancer cells. Furthermore, we found that the ROS-JNK pathway was obviously activated in the DCA combined sorafenib group. The levels of ROS and p-JNK were dramatically up-regulated in the two drug combination groups. Antioxidant NAC could alleviate the synergetic effects of DCA and sorafenib on ROS generation, JNK activation, Mcl-1 degradation, and cell apoptosis. Moreover, DCA and sorafenib's effects on Mcl-1 degradation and apoptosis could also be inhibited by JNK inhibitor 'SP'600125. Finally, the synergetic effects of DCA and sorafenib on tumor growth suppression, Mcl-1 degradation and induction of apoptosis were also validated in liver cancer xenograft in vivo. These findings indicate that DCA enhances the anti-tumor effect of sorafenib via the ROS-JNK-Mcl-1 pathway in liver cancer cells. This study may provide new insights to improve the chemotherapeutic effect of sorafenib, which may be beneficial for further clinical application of sorafenib in liver cancer treatment.


Assuntos
Ácido Dicloroacético/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Hepáticas/tratamento farmacológico , MAP Quinase Quinase 4/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Sorafenibe/farmacologia , Acetilcisteína/farmacologia , Animais , Antracenos/farmacologia , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , MAP Quinase Quinase 4/antagonistas & inibidores , MAP Quinase Quinase 4/metabolismo , Masculino , Camundongos Nus , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Mediators Inflamm ; 2022: 8007078, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497095

RESUMO

Ischemic stroke is a major condition that remains extremely problematic to treat. A cerebral reperfusion injury becomes apparent after an ischemic accident when reoxygenation of the afflicted area produces pathological side effects that are different than those induced by the initial oxygen and nutrient deprivation insult. Pyroptosis is a form of lytic programmed cell death that is distinct from apoptosis, which is initiated by inflammasomes and depends on the activation of Caspase-1. Then, Caspase-1 mobilizes the N-domain of gasdermin D (GSDMD), resulting in the release of cytokines, such as interleukin-1ß (IL-1ß) and interleukin-18 (IL-18). X-box binding protein l (XBP-1) is activated under endoplasmic reticulum (ER) stress to form an important transcription factor XBP-1 splicing (XBP-1s). The cerebral ischemia/reperfusion (CI/R) causes cytotoxicity, which correlates with the activation of splicing XBP-1 mRNA and NLRP3 (NOD-, LRR-, and pyrin domain-containing 3) inflammasomes, along with increases in the expression and secretion of proinflammatory cytokines and upregulation of pyroptosis-related genes in HT22 cells and in the middle cerebral artery occlusion (MCAO) rat model. However, whether XBP-1 plays a role in regulating pyroptosis involved in CI/R is still unknown. Our present study showed that behavior deficits, cerebral ischemic lesions, and neuronal death resulted from CI/R. CI/R increased the mRNA level of XBP-1s, NLRP3, IL-1ß, and IL-18 and the expressions of XBP-1s, NLRP3, Caspase-1, GSDMD-N, IL-1ß, and IL-18. We further repeated this process in HT22 cells and C8-B4 cells and found that OGD/R decreased cell viability and increased LDH release, XBP-1s, NLRP3, Caspase-1, GSDMD-N, IL-1ß, IL-18, and especially the ratio of pyroptosis, which were reversed by Z-YVAD-FMK and downregulated XBP-1. Our results suggest that downregulated XBP-1 inhibited pyroptosis through the classical NLRP3/Caspase-1/GSDMD pathway to protect the neurons.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Animais , Caspase 1 , Inflamassomos , Interleucina-18 , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Piroptose , RNA Mensageiro , Ratos , Proteína 1 de Ligação a X-Box
9.
Sensors (Basel) ; 21(3)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535468

RESUMO

Synthetic aperture radar tomography (TomoSAR) is an important 3D mapping method. Traditional TomoSAR requires a large number of observation orbits however, it is hard to meet the requirement of massive orbits. While on the one hand, this is due to funding constraints, on the other hand, because the target scene is changing over time and each observation orbit consumes lots of time, the number of orbits can be fewer as required within a narrow time window. When the number of observation orbits is insufficient, the signal-to-noise ratio (SNR), peak-to-sidelobe ratio (PSR), and resolution of 3D reconstruction results will decline severely, which seriously limits the practical application of TomoSAR. In order to solve this problem, we propose to use a deep learning network to improve the resolution and SNR of 3D reconstruction results under the condition of very few observation orbits by learning the prior distribution of targets. We use all available orbits to reconstruct a high resolution target, while only very few (around 3) orbits to reconstruct a low resolution input. The low-res and high-res 3D voxel-grid pairs are used to train a 3D super-resolution (SR) CNN (convolutional neural network) model, just like ordinary 2D image SR tasks. Experiments on the Civilian Vehicle Radar dataset show that the proposed deep learning algorithm can effectively improve the reconstruction both in quality and in quantity. In addition, the model also shows good generalization performance for targets not shown in the training set.

10.
Plant Cell Rep ; 36(9): 1417-1426, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28653111

RESUMO

KEY MESSAGE: Our study systematically explored potential genes and molecular pathways as candidates for differences in seed weight resulting from soybean domestication. In addition, potential contributions of lncRNAs to seed weight were also investigated. Soybeans have a long history of domestication in China, and there are several significant phenotypic differences between cultivated and wild soybeans, for example, seeds of cultivars are generally larger and heavier than those from wild accessions. We analyzed seed transcriptomes from thirteen soybean samples, including six landraces and seven wild accessions using strand-specific RNA sequencing. Differentially expressed genes related to seed weight were identified, and some of their homologs were associated with seed development in Arabidopsis. We also identified 1251 long intergenic noncoding RNAs (lincRNAs), 243 intronic RNAs and 81 antisense lncRNAs de novo from these soybean transcriptomes. We then profiled the expression patterns of lncRNAs in cultivated and wild soybean seeds, and found that transcript levels of a number of lncRNAs were sample-specific. Moreover, gene transcript and lincRNA co-expression network analysis showed that some soybean lincRNAs might have functional roles as they were hubs of co-expression modules. In conclusion, this study systematically explored potential genes and molecular pathways as candidates for differences in seed weight resulting from soybean domestication, and will provide a useful future resource for molecular breeding of soybeans.


Assuntos
Regulação da Expressão Gênica de Plantas , Glycine max/genética , Sementes/genética , Transcriptoma/genética , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Redes Reguladoras de Genes , Análise de Sequência de RNA , Glycine max/classificação , Especificidade da Espécie
11.
Acta Biochim Biophys Sin (Shanghai) ; 49(6): 479-486, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28449039

RESUMO

Glioblastoma is the most aggressive brain tumor, and its prognosis remains poor. Therefore, novel therapeutic strategies are needed for glioma therapy. Polyphyllin I (PPI), a bioactive constituent extracted from Paris polyphylla, was reported to have anti-tumor activity. However, the detailed mechanism for this activity remains unclear. Here, we investigated the inhibitory effects of PPI on glioma cells and its mechanisms in vitro. U251 cells were treated with various concentrations of PPI (2-9 µM) for 24 to 72 h. The inhibition of U251 cell proliferation by PPI was assessed by MTT assay. The effects on cell cycle and apoptosis were examined by flow cytometry with PI and annexin V-FITC/PI dual staining, and the cell mitochondrial membrane potential level was evaluated by fluorescence microscopy with JC-1 staining. The expression levels of apoptosis-related proteins and JNK signal pathway proteins were evaluated by western blot analysis. Results showed that PPI significantly inhibited the proliferation of U251 cells in a concentration-dependent manner. PPI induced G2/M phase arrest and apoptosis, and it upregulated the expressions of Bax, cytochrome c, and p-JNK, but downregulated the expression of the anti-apoptotic protein Bcl-2 in U251 cells. Moreover, PPI provoked the depolarization of the mitochondrial membrane potential. In addition, apoptosis induced by the PPI was remarkably suppressed by the JNK inhibitor SP600125. Our data provide evidence that PPI inhibits proliferation and induces apoptotic cell death in U251 cells. This effect may be associated with the JNK pathway. These results suggest that PPI is an activator of the JNK signaling pathway with a potential anti-glioma effect.


Assuntos
Apoptose/efeitos dos fármacos , Diosgenina/análogos & derivados , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diosgenina/química , Diosgenina/farmacologia , Relação Dose-Resposta a Droga , Glioma/metabolismo , Glioma/patologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
12.
Biochem Biophys Res Commun ; 450(1): 234-9, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24878525

RESUMO

In non-polarized cell culture models, influenza virus has been shown to enter host cells via multiple endocytic pathways, including classical clathrin-mediated endocytic routes (CME), clathrin- and caveolae-independent routes and macropinocytosis. However, little is known about the entry route of influenza virus in differentiated epithelia, in vivo site of infection for influenza virus. Here, we show that in polarized Madin-Darby canine kidney type II (MDCK II) cells, influenza virus has a specific utilization of the clathrin-mediated endocytic pathway and requires Eps15 for host cell entry.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Polaridade Celular/fisiologia , Clatrina/metabolismo , Endocitose , Vírus da Influenza A Subtipo H1N1/fisiologia , Transdução de Sinais , Internalização do Vírus , Proteínas Adaptadoras de Transporte Vesicular , Animais , Cães , Células Madin Darby de Rim Canino
13.
Bioorg Med Chem Lett ; 24(23): 5493-6, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25455491

RESUMO

2-Aminopyrimidin-4(1H)-one was proposed as the novel bioisostere of urea. Bioisosteric replacement of the reported urea series of the CXCR2 antagonists with 2-aminopyrimidin-4(1H)-ones led to the discovery of the novel and potent CXCR2 antagonist 3e. 2-Aminopyrimidin-4(1H)-one derivative 3e demonstrated a good developability profile (reasonable solubility and high permeability) and superior chemical stability especially in simulated gastric fluid (SGF) compared with ureas.


Assuntos
Pirimidinas/síntese química , Receptores de Interleucina-8B/antagonistas & inibidores , Ureia/análogos & derivados , Humanos , Estrutura Molecular , Pirimidinas/química , Pirimidinas/farmacologia , Relação Estrutura-Atividade
14.
Artigo em Inglês | MEDLINE | ID: mdl-39325292

RESUMO

Aspergillus oryzae is an ideal cell factory for protein expression with powerful protein processing and secretion capabilities. The current study aimed to explore the homologous expression of A. oryzae lipase AOL (GenBank: KP975533) by constructing an auxotrophic A. oryzae △pyrG△nptB and subsequently characterizing the immobilization and catalytic properties of recombinant lipase. Initially, the pyrG gene knocked out in wild-type A. oryzae by homologous recombination, followed by the creation of a uridine/uracil auxotroph transformation. Through this system, the protease gene nptB was precisely knocked out, leading to a substantial decrease in extracellular (39.04%) and intracellular (90.07%) protease activity. The A. oryzae △nptB△pyrG strain was used as host for homologous expression of lipase AOL. After transformation of linearized lipase-expression cassette, the engineered A. oryzae AOL-8 was screened out with the lipase gene copy number of 14, exhibiting extracellular and intracellular lipase activities of 1.75 U/mL and 46.4 U/g, respectively. Subsequently, the production and immobilization of the recombinant lipase, via physical adsorption on macroporous resin XRZ04B, were achieved through submerged fermentation of the AOL-8 strain. The results of esterification catalytic properties of immobilized recombinant lipase indicated that the lipase exhibited optimal catalytic activity with lauric acid and methanol as substrates, a reaction temperature of 35 °C, and n-hexane as the preferred solvent medium; its highest conversion rate can reach at 72.3%.

15.
3 Biotech ; 14(7): 172, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38841267

RESUMO

Lipase has high economic importance and is widely used in biodiesel, food, detergents, cosmetics, and pharmaceutical industries. The rapid development of synthetic biology and system biology has not only paved the way for comprehensively understanding the efficient operation mechanism of Aspergillus niger cell factories but also introduced a new technological system for creating and optimizing high-efficiency A. niger cell factories. In this review, all relevant data on microbial lipase enzyme sources and general properties are gathered and updated. The relationship between A. niger strain morphology and protein production is discussed. The safety of A. niger strain is investigated to ensure product safety. The biotechnologies and factors influencing lipase expression in A. niger are summarized. This review focuses on various strategies to improve lipase expression in A. niger. The summary of these methods and the application of the gene editing technology CRISPR/Cas9 system can further improve the efficiency of constructing the engineered lipase-producing A. niger.

16.
J Neurosci Methods ; 405: 110099, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38417713

RESUMO

BACKGROUND: Escape is one of the most essential behaviors for an animal's survival because it could be a matter of life and death. Much of our current understanding of the neural mechanisms underlying escape is derived from the looming paradigm, which mimics a diving aerial predator. Yet, the idea of the looming paradigm does not account for all types of threats like lions hunting antelopes or cats stalking mice. Escape responses to such terrestrial threats may require different strategies and neural mechanisms. NEW METHODS: Here, we developed a real-time interactive platform to study escape behavior to terrestrial threats in mice. A closed-loop controlled robot was magnetically pulled to mimic a terrestrial threat that chases a mouse. By using strong magnets and high-precision servo motors, the robot is capable of moving precisely with a high spatial-temporal resolution. Different algorithms can be used to achieve single approach or persistent approach. RESULTS: Animal experiments showed that mice exhibited consistent escape behavior when exposed to an approaching robotic predator. When presented with a persistently approaching predator, the mice were able to rapidly adapt their behavior, as evidenced by a decrease in startle responses and changes in movement patterns. COMPARISON WITH EXISTING METHODS: In comparison to existing methods for studying escape behavior, such as the looming paradigm, this approach is more suitable for investigating animal behavior in response to sustained threats. CONCLUSION: In conclusion, we have developed a flexible platform to study escape behavior to terrestrial threats in mice.


Assuntos
Reação de Fuga , Roedores , Animais , Camundongos , Reação de Fuga/fisiologia , Comportamento Animal , Comportamento Predatório/fisiologia
17.
Int J Mol Med ; 53(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38426556

RESUMO

Following the publication of the above article, an interested reader drew to the authors' attention that, in Fig. 6 on p. 2898, the 'SAH' and 'SAH+NC' data panels contained an apparently overlapping section of data, such that these data appeared to have been derived from the same original source, even though they were intended to show the results from differently performed experiments. The authors have examined their original data, and realize that the 'SAH+NC' data panel had inadvertently been selected incorrectly for this figure. In addition, in response to a further query from the reader, the authors wished to point out that the standard deviations in their study were statistically analysed using GraphPad Prism software version 5.0a. The revised version of Fig. 6, now showing the correct data for the 'SAH+NC' experiment, is shown on the next page. The authors can confirm that the errors associated with this figure did not have any significant impact on either the results or the conclusions reported in this study, and all the authors agree with the publication of this Corrigendum. The authors are grateful to the Editor of International Journal of Molecular Medicine for allowing them the opportunity to publish this Corrigendum; furthermore, they apologize to the readership of the Journal for any inconvenience caused. [International Journal of Molecular Medicine 42: 2891­2902, 2018; DOI: 10.3892/ijmm.2018.3858].

18.
Acta Psychol (Amst) ; 243: 104132, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232507

RESUMO

Consecutive interpreting involves a demanding language task where mental workload (MWL) is crucial for assessing interpreters' performance. An elevated cognitive load in interpreters may lead to the interpretation failures. The widely used NASA-TLX questionnaire effectively measures MWL. However, a global score was employed in previous interpretation studies, overlooking the distinct contributions of MWL components to the interpreters' performance. Accordingly, we recruited twenty novice interpreters who were postgraduate students specializing in interpreting to complete the consecutive interpreting task. Throughout the process, we used functional near-infrared spectroscopy (fNIRS) to monitor the hemodynamic response in participants' brains. The NASA-TLX was used to measure the MWL during interpreting with six components, including mental demand, physical demand, temporal demand, performance, effort, and frustration. Five interpretation experts were invited to assess the interpretation quality. The Bayes factor approach was employed to explore the components that contributes the most to the interpretation quality. It indicated that mental demand strongly contributed to the interpretation quality. Moreover, the mediation analysis revealed a positive correlation between mental demand and brain activation in three brain areas, which, in turn, was negatively correlated with interpretation quality, indicating the predictive role of mental demand in interpretation quality through the mediating of brain activation. The functions of the mediating brain areas, including the inferior frontal gyrus, middle temporal gyrus, and inferior temporal gyrus, aligned with the three efforts proposed by Gile's effort model, which emphasizes the significance of three fundamental efforts in achieving successful interpreting. These findings have implications for interpreter learning and training.


Assuntos
Análise e Desempenho de Tarefas , Carga de Trabalho , Humanos , Teorema de Bayes , Carga de Trabalho/psicologia , Idioma , Encéfalo
19.
Biosens Bioelectron ; 248: 115968, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38150799

RESUMO

Screening for high-risk human papillomavirus (HPV) infection is one of the most important preventative measures for cervical cancer. However, fast, convenient, and low-cost HPV detection remains challenging, especially in resource-limited settings. Here, we report a portable all-in-one device (PAD) for point-of-care testing (POCT) for HPV16 and HPV18 DNA in cervical swabs. The PAD was engineered to integrate modules for extraction-free sample lysis, loop-mediated isothermal amplification (LAMP) with lyophilized reagent beads, and real-time colorimetric signal sensing into a single miniaturized device, considerably shortening the sample-to-result time to 15 min. The precision liquid handling in the completely sealed microfluidic chip is achieved by a uniquely designed pressure-balanced automatic liquid flow mechanism, thereby eliminating the need for manual manipulation of liquids and thus the risk of biohazards. The PAD employs an improved real-time colorimetric LAMP (rcLAMP) assay with a limit of detection (LOD) of 1 copy/µL, enabled by enhanced assay chemistry to maximize the reaction kinetics. To validate this device for clinical application, we tested 206 clinical cervical swab samples and obtained a sensitivity of 92.1% and a specificity of 99.0%. This custom PAD enabled by microfluidic and electronic engineering techniques can be configured for the simultaneous detection of HPV16 and HPV18 or other pathogens in point-of-care applications.


Assuntos
Técnicas Biossensoriais , Infecções por Papillomavirus , Feminino , Humanos , Microfluídica , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Colorimetria/métodos , Infecções por Papillomavirus/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Imediatos , DNA Viral/genética , Dispositivos Lab-On-A-Chip , Sensibilidade e Especificidade
20.
J Immunol ; 187(3): 1129-41, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21709156

RESUMO

Current therapies for multiple sclerosis target inflammation but do not directly address oligodendrocyte protection or myelin repair. The gp130 family cytokines ciliary neurotrophic factor, leukemia inhibitory factor, and IL-11 have been identified as oligodendrocyte growth factors, and IL-11 is also strongly immunoregulatory, but their underlying mechanisms of action are incompletely characterized. In this study, we demonstrate that these effects of IL-11 are mediated via differential regulation of apoptosis in oligodendrocytes versus Ag-presenting dendritic cells (DCs), and are dependent on lineage-specific activity of the transcription factors Stat1 versus Stat3. Focal demyelinating lesions induced in cerebral cortices of IL-11Rα(-/-) mice using stereotactic microinjection of lysolecithin were larger than in controls, and remyelination was delayed. In IL-11Rα(-/-) mice, lesions displayed extensive oligodendrocyte loss and axonal transection, and increased infiltration by inflammatory cells including CD11c(+) DCs, CD3(+) lymphocytes, and CD11b(+) phagocytes. In oligodendrocyte progenitor cell (OPC) cultures, IL-11 restricted caspase 9 activation and apoptosis, and it increased myelination in OPC-neuron cocultures. Importantly, siRNA inhibition of Stat1 enhanced the antiapoptotic effects of IL-11 on OPCs, but IL-11 induced apoptosis in the presence of Stat3 silencing. In contrast, IL-11 augmented caspase activation and apoptosis in cultures of CD11c(+) DCs, but not in CD11b(+) or CD3(+) cells. Inhibition of Stat3 exacerbated the proapoptotic effects of IL-11 on DCs, whereas they were ablated in Stat1(-/-) cultures. Collectively, these findings reveal novel mechanisms underlying the actions of a neuroprotective and immunoregulatory member of the gp130 cytokine family, suggesting avenues to enhance oligodendrocyte viability and restrict CNS inflammation in multiple sclerosis.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Interleucina-11/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Fator de Transcrição STAT1/fisiologia , Fator de Transcrição STAT3/fisiologia , Animais , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Células Cultivadas , Técnicas de Cocultura , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/terapia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Modelos Animais de Doenças , Marcação de Genes/métodos , Interleucina-11/deficiência , Interleucina-11/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Esclerose Múltipla/terapia , Oligodendroglia/imunologia , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Ratos , Ratos Sprague-Dawley , Células-Tronco/imunologia , Células-Tronco/metabolismo , Células-Tronco/patologia
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