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1.
Heliyon ; 10(9): e29829, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38707472

ABSTRACT

Background: Glioma, a prevalent malignancy of the brain and spinal cord, poses a considerable threat to human health. The association between aberrant sialic acid modification and glioma progression has been suggested, but the precise mechanism is still elusive. ST3GAL4, a sialoglycosyltransferase, is implicated in increased metastatic potential and poor prognosis in various cancers; however, its specific role in glioma requires further elucidation. Methods: We evaluated ST3GAL4 expression levels and their clinical relevance using the TCGA database, and we assessed immune infiltration via the Tumor Immune Evaluation Resource (TIMER) database. In vitro experiments were performed to determine the effects of ST3GAL4 knockdown on glioma cell malignancy, with additional co-culture assays to assess its impact on macrophage phenotype. Results: ST3GAL4 expression was markedly elevated in glioma tissues compared to normal brain tissues, with a strong correlation to glioma patient clinical characteristics. Survival analyses and receiver operating characteristic (ROC) curves suggested that ST3GAL4 is a feasible diagnostic and prognostic biomarker for glioma. Knockdown studies revealed that ST3GAL4 inhibition reduces glioma cell line proliferation, migration, and invasion, while causing G1 phase cell cycle arrest. ST3GAL4 appears to mediate glioma progression through extracellular matrix reorganization and EMT signaling pathway activation, further contributing to M2 macrophage polarization and infiltration within the tumor microenvironment. Conclusion: Our research highlights the critical role of ST3GAL4 in glioma development, positioning it as a promising candidate for diagnostic and therapeutic interventions.

2.
Nucleic Acids Res ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38783063

ABSTRACT

Native prokaryotic promoters share common sequence patterns, but are species dependent. For understudied species with limited data, it is challenging to predict the strength of existing promoters and generate novel promoters. Here, we developed PromoGen, a collection of nucleotide language models to generate species-specific functional promoters, across dozens of species in a data and parameter efficient way. Twenty-seven species-specific models in this collection were finetuned from the pretrained model which was trained on multi-species promoters. When systematically compared with native promoters, the Escherichia coli- and Bacillus subtilis-specific artificial PromoGen-generated promoters (PGPs) were demonstrated to hold all distribution patterns of native promoters. A regression model was developed to score generated either by PromoGen or by another competitive neural network, and the overall score of PGPs is higher. Encouraged by in silico analysis, we further experimentally characterized twenty-two B. subtilis PGPs, results showed that four of tested PGPs reached the strong promoter level while all were active. Furthermore, we developed a user-friendly website to generate species-specific promoters for 27 different species by PromoGen. This work presented an efficient deep-learning strategy for de novo species-specific promoter generation even with limited datasets, providing valuable promoter toolboxes especially for the metabolic engineering of understudied microorganisms.

3.
Adv Sci (Weinh) ; : e2310215, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38626358

ABSTRACT

Microbial factories lacking the ability of dynamically regulating the pathway enzymes overexpression, according to in situ metabolite concentrations, are suboptimal, especially when the metabolic intermediates are competed by growth and chemical production. The production of higher alcohols (HAs), which hijacks the amino acids (AAs) from protein biosynthesis, minimizes the intracellular concentration of AAs and thus inhibits the host growth. To balance the resource allocation and maintain stable AA flux, this work utilizes AA-responsive transcriptional attenuator ivbL and HA-responsive transcriptional activator BmoR to establish a concentration recognition-based auto-dynamic regulation system (CRUISE). This system ultimately maintains the intracellular homeostasis of AA and maximizes the production of HA. It is demonstrated that ivbL-driven enzymes overexpression can dynamically regulate the AA-to-HA conversion while BmoR-driven enzymes overexpression can accelerate the AA biosynthesis during the HA production in a feedback activation mode. The AA flux in biosynthesis and conversion pathways is balanced via the intracellular AA concentration, which is vice versa stabilized by the competition between AA biosynthesis and conversion. The CRUISE, further aided by scaffold-based self-assembly, enables 40.4 g L-1 of isobutanol production in a bioreactor. Taken together, CRUISE realizes robust HA production and sheds new light on the dynamic flux control during the process of chemical production.

4.
Nurse Educ Today ; 135: 106093, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38301294

ABSTRACT

BACKGROUND: Currently, nursing students face a significant lack of preparedness in efficiently addressing complex issues. The use of challenge-based learning, a student-centred situational learning method that utilizes practice scenarios to solve complex problems, can help alleviate the challenges in nurse education. However, there remains to be more extensive exploration on the application of challenge-based learning in nurse practice education. OBJECTIVES: This study aims to explore the learning experiences of nursing students in challenge-based learning to gain a deeper understanding of the ways and mechanisms through which challenge-based learning enhances specific learning abilities. DESIGN/METHODS: This study utilized a hermeneutic phenomenological design, employing semi-structured interviews and thematic analysis. SETTINGS: A university in Hunan, China, hosted the nursing skills competition based on the principles of challenge-based learning, targeting senior students from nursing schools in Hunan province. PARTICIPANTS: A total of 24 fourth-year students from six colleges, including one male and twenty-three female students. RESULTS: Two themes and seven sub-themes emerged from the study. Theme 1 Constructing a knowledge system in complex scenarios with sub-themes: Case-based education centred on comprehensive knowledge promotes knowledge linkage; Reverse reasoning promotes knowledge differentiation; Making mistakes helps finding the correct path of knowledge; Traps inspire identification of potential problems. Theme 2 Inquiry in uncertainty with sub-themes: Unexpected changes promote exploration of general principles; Combining knowledge with diverse case scenarios promotes flexible thinking; The uncertainty of knowledge fosters independent thinking. CONCLUSIONS: The complexity and variability inherent in challenging learning situations promote the construction of students' knowledge systems and the cultivation of an inquisitive spirit. The identification of these mechanisms contributes to the optimization of instructional environment design, the development of a culture of continuous learning and innovation, and effectively tackling complex issues within an ever-evolving global context.


Subject(s)
Education, Nursing, Baccalaureate , Students, Nursing , Humans , Male , Female , Education, Nursing, Baccalaureate/methods , Uncertainty , Learning , Qualitative Research
5.
Appl Microbiol Biotechnol ; 108(1): 195, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38324205

ABSTRACT

Pentacyclic triterpenoids exhibit a wide range of biological activities which have wide applications in the food, cosmetics, and pharmaceutical industries. High-performance chassis strains have been developed for the production of various pentacyclic triterpenoids, e.g., lupane-type and oleanane-type triterpenoids. The production of common pentacyclic triterpenes and their derivatives is limited by the poor activity of typical pentacyclic triterpene synthases (PTSs). However, a general strategy applicable to typical PTSs is still lacking. As typical pentacyclic triterpenes are derived from the baccharenyl cation, engineering the non-active-site residues in the MXXXXR motif might be beneficial for the catalytic efficiencies of typical PTSs by the stabilization of the baccharenyl cation. Here, we develop a general strategy for improving the activity of typical PTSs. As a proof of concept, the activity of three PTSs such as lupeol synthase, ß-amyrin synthase, and α-amyrin synthases was significantly increased up to 7.3-fold by site-directed saturation mutagenesis. This strategy could be applied to improve the activity of various typical PTSs. KEY POINTS: • The strategy could be applied to typical PTSs for improving the activity. • The catalytic activity of typical PTSs was significantly increased.


Subject(s)
Triterpenes , Amino Acids , Pentacyclic Triterpenes , Catalysis , Cations
6.
Trends Biotechnol ; 42(1): 43-60, 2024 01.
Article in English | MEDLINE | ID: mdl-37451946

ABSTRACT

Enzyme self-assembly is a technology in which enzyme units can aggregate into ordered macromolecules, assisted by scaffolds. In metabolic engineering, self-assembly strategies have been explored for aggregating multiple enzymes in the same pathway to improve sequential catalytic efficiency, which in turn enables high-level production. The performance of the scaffolds is critical to the formation of an efficient and stable assembly system. This review comprehensively analyzes these scaffolds by exploring how they assemble, and it illustrates how to apply self-assembly strategies for different modules in metabolic engineering. Functional modifications to scaffolds will further promote efficient strategies for production.


Subject(s)
Metabolic Engineering , Technology , Macromolecular Substances
7.
Cell Rep Med ; 4(12): 101302, 2023 12 19.
Article in English | MEDLINE | ID: mdl-38052215

ABSTRACT

The RATIONALE-307 study (ClinicalTrials.gov: NCT03594747) demonstrates prolonged progression-free survival (PFS) with first-line tislelizumab plus chemotherapy versus chemotherapy in advanced lung squamous cell carcinoma (LUSC; N = 360). Here we describe an immune-related gene expression signature (GES), composed of genes involved in both innate and adaptive immunity, that appears to differentiate tislelizumab plus chemotherapy PFS benefit versus chemotherapy. In contrast, a tislelizumab plus chemotherapy PFS benefit is observed regardless of programmed death ligand 1 (PD-L1) expression or tumor mutational burden (TMB). Genetic analysis reveals that NRF2 pathway activation is enriched in PD-L1positive and TMBhigh patients. NRF2 pathway activation is negatively associated with PFS, which affects efficacy outcomes associated with PD-L1 and TMB status, impairing their predictive potential. Mechanistic studies demonstrate that NRF2 directly mediates PD-L1 constitutive expression independent of adaptive PD-L1 regulation in LUSC. In summary, the GES is an immune signature that might identify LUSC patients likely to benefit from first-line tislelizumab plus chemotherapy.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Carcinoma, Squamous Cell , Lung Neoplasms , Humans , B7-H1 Antigen/genetics , Biomarkers, Tumor/genetics , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Lung/pathology , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mutation , NF-E2-Related Factor 2/genetics , Programmed Cell Death 1 Receptor , Treatment Outcome , Tumor Microenvironment/genetics
8.
Immunobiology ; 228(6): 152746, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37980830

ABSTRACT

BACKGROUND: Glioblastoma(GBM) has a profound impact on human health, making the identification of reliable prognostic biomarkers pivotal. While PLEKHA4 has been associated with tumor genesis and development, its role in gliomas is still uncertain. METHODS: We analyzed PLEKHA4 expression in tumor tissues using the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Additionally, we utilized TCGA data to investigate its impact on prognosis, pathway enrichment, and immune infiltration. In vitro loss-of-function experiments were conducted to elucidate the effect of PLEKHA4 silencing on GBM cell behavior. RESULTS: TCGA and GEO data sets revealed increased levels of PLEKHA4 expression in glioma tissues. Furthermore, we identified a correlation between PLEKHA4 expression and higher disease classification, pathological grading, and poorer prognosis. Silencing PLEKHA4 in vitro resulted in decreased glioma cell migration and increased apoptosis. It also reduced macrophage infiltration and hindered M2 polarization of macrophages. CONCLUSION: Our findings highlight the pivotal role of PLEKHA4 in GBM pathogenesis and suggest its potential as a diagnostic and therapeutic target for GBM.


Subject(s)
Glioblastoma , Glioma , Humans , Apoptosis/genetics , Cell Movement/genetics , Glioblastoma/genetics , Glioma/genetics , Macrophages , Prognosis
9.
Zhongguo Zhen Jiu ; 43(9): 1008-13, 2023 Sep 12.
Article in Chinese | MEDLINE | ID: mdl-37697874

ABSTRACT

OBJECTIVE: To observe the effects of Tiaoshen (regulating the spirit) acupuncture on cognitive function and sleep quality in patients with primary insomnia (PI). METHODS: Sixty patients with PI were randomly divided into an observation group (30 cases, 2 cases dropped off) and a control group (30 cases, 2 cases dropped off, 1 case was excluded). The patients in the observation group were treated with acupuncture at Baihui (GV 20), Shenting (GV 24), Sishencong (EX-HN 1), and bilateral Benshen (GB 13), Shenmen (HT 7), Neiguan (PC 6), Sanyinjiao (SP 6). The patients in the control group were treated with shallow needling at non-effective points. Each treatment was provided for 30 min, once every other day, 3 treatments per week for 4 weeks. The Montreal cognitive assessment (MoCA), digit span test (DST), trail making test (TMT)-A, Pittsburgh sleep quality index (PSQI), and fatigue scale-14 (FS-14) were used to assess cognitive function and sleep quality before and after treatment, as well as in follow-up of 4-week after treatment completion. Correlation analysis was conducted between the differences in PSQI scores and differences in MoCA scores before and after treatment in the observation group. RESULTS: Compared with before treatment, the total score, visuospatial and executive function score and delayed memory score of MoCA as well as DST backward score were increased (P<0.01), while TMT-A time, PSQI and FS-14 scores were significantly reduced (P<0.01) after treatment and in follow-up in the observation group. Compared with before treatment, the PSQI score in the control group was reduced (P<0.01, P<0.05). After treatment and in follow-up, the observation group had significantly higher total score, visuospatial and executive function score, delayed memory score of MoCA, and DST backward score compared to the control group (P<0.05, P<0.01). In the observation group, the TMT-A time was significantly shorter than that in the control group (P<0.05, P<0.01), and the PSQI and FS-14 scores were significantly lower than those in the control group (P<0.01). In the observation group, there was a negative correlation between the difference in PSQI scores (post-treatment minus pre-treatment) and the difference in MoCA scores (post-treatment minus pre-treatment) (r=-0.481, P<0.01). A similar negative correlation was found between the difference in PSQI scores (follow-up minus pre-treatment) and the difference in MoCA scores (follow-up minus pre-treatment) (r=-0.282, P<0.05). CONCLUSION: Tiaoshen acupuncture could improve cognitive function, enhance sleep quality, and alleviate daytime fatigue in patients with PI. The improvement in cognitive function in patients with PI is correlated with the improvement in sleep quality.


Subject(s)
Acupuncture Therapy , Sleep Initiation and Maintenance Disorders , Humans , Pilot Projects , Sleep Initiation and Maintenance Disorders/therapy , Cognition , Fatigue
10.
Microb Cell Fact ; 22(1): 147, 2023 Aug 05.
Article in English | MEDLINE | ID: mdl-37543600

ABSTRACT

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is one of the most popular flavors with wide applications in food, fragrance, and pharmaceutical industries. However, the high cost and limited yield of plant extraction failed to meet the vast market demand of natural vanillin. Vanillin biotechnology has emerged as a sustainable and cost-effective alternative to supply vanillin. In this review, we explored recent advances in vanillin biosynthesis and highlighted the potential of vanillin biotechnology. In particular, we addressed key challenges in using microorganisms and provided promising approaches for improving vanillin production with a special focus on chassis development, pathway construction and process optimization. Future directions of vanillin biosynthesis using inexpensive precursors are also thoroughly discussed.


Subject(s)
Benzaldehydes , Biotechnology , Benzaldehydes/metabolism
11.
Anal Chem ; 95(25): 9646-9653, 2023 06 27.
Article in English | MEDLINE | ID: mdl-37311071

ABSTRACT

Fluorescent rotors with aggregation-induced emission (AIE) and organelle-targeting properties have attracted great attention for sensing subcellular viscosity changes, which could help understand the relationships of abnormal fluctuations with many associated diseases. Despite the numerous efforts spent, it remains rare and urgent to explore the dual-organelle targeting probes and their structural relationships with viscosity-responsive and AIE properties. Therefore, in this work, we reported four meso-five-membered heterocycle-substituted BODIPY-based fluorescent probes, explored their viscosity-responsive and AIE properties, and further investigated their subcellular localization and viscosity-sensing applications in living cells. Interestingly, the meso-thiazole probe 1 showed both good viscosity-responsive and AIE (in pure water) properties and could successfully target both mitochondria and lysosomes, further imaging cellular viscosity changes by treating lipopolysaccharide and nystatin, attributing to the free rotation and potential dual-organelle targeting ability of the meso-thiazole group. The meso-benzothiophene probe 3 with a saturated sulfur only showed good viscosity-responsive properties in living cells with the aggregation-caused quenching effect and no subcellular localization. The meso-imidazole probe 2 showed the AIE phenomenon without an obvious viscosity-responsive property with a C═N bond, while the meso-benzopyrrole probe 4 displayed fluorescence quenching in polar solvents. Therefore, for the first time, we investigated the structure-property relationships of four meso-five-membered heterocycle-substituted BODIPY-based fluorescent rotors with viscosity-responsive and AIE properties, and among these, 1 with a C═N bond and a saturated sulfur on the meso-thiazole, potentially contributing to their corresponding AIE and viscosity-responsive properties, served as a sensitive AIE fluorescent rotor for imaging dual-organelle viscosity in both mitochondria and lysosomes.


Subject(s)
Fluorescent Dyes , Organelles , Fluorescent Dyes/chemistry , Viscosity , Diagnostic Imaging
12.
Metab Eng ; 78: 11-25, 2023 07.
Article in English | MEDLINE | ID: mdl-37149082

ABSTRACT

Amino acids have a multi-billion-dollar market with rising demand, prompting the development of high-performance microbial factories. However, a general screening strategy applicable to all proteinogenic and non-proteinogenic amino acids is still lacking. Modification of the critical structure of tRNA could decrease the aminoacylation level of tRNA catalyzed by aminoacyl-tRNA synthetases. Involved in a two-substrate sequential reaction, amino acids with increased concentration could elevate the reduced aminoacylation rate caused by specific tRNA modification. Here, we developed a selection system for overproducers of specific amino acids using corresponding engineered tRNAs and marker genes. As a proof-of-concept, overproducers of five amino acids such as L-tryptophan were screened out by growth-based and/or fluorescence-activated cell sorting (FACS)-based screening from random mutation libraries of Escherichia coli and Corynebacterium glutamicum, respectively. This study provided a universal strategy that could be applied to screen overproducers of proteinogenic and non-proteinogenic amino acids in amber-stop-codon-recoded or non-recoded hosts.


Subject(s)
Amino Acids , Amino Acyl-tRNA Synthetases , Amino Acids/genetics , Amino Acids/metabolism , RNA, Transfer/chemistry , RNA, Transfer/genetics , RNA, Transfer/metabolism , Amino Acyl-tRNA Synthetases/genetics , Amino Acyl-tRNA Synthetases/metabolism , Mutation , Escherichia coli/genetics , Escherichia coli/metabolism
13.
Clin Oral Investig ; 27(7): 3961-3972, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37071219

ABSTRACT

OBJECTIVES: The purpose of this study was to develop a novel Bonwill⁃Hawley method (Bonwill⁃Hawley arch form based on CBCT image) for the assessment of dental crowding, and to investigate and compare the accuracy and eligibility with the conventional brass wire and caliper methods under different crowding conditions. MATERIAL AND METHODS: Sixty patients with the pair of plaster casts and CBCT data were collected. All the casts were marked and transformed into digital models using iTero scanner, and imported into OrthoCAD software to measure the required space. Using the conventional brass wire (M1) and caliper methods (M2), the available space and dental crowding were measured and calculated basing on digital models, respectively. Correspondingly, the axial planes in the level of dental arches were oriented and captured from the CBCT images to draw the Bonwill⁃Hawley arch forms (M3), which were used to measure and calculate the available space and dental crowding. For each method, intra and inter-examiner reliabilities were evaluated with intra-class correlation coefficients (ICCs). Wilcoxon test and Kruskal-Wallis test were performed for statistically analyzing the discrepancy among different groups. RESULTS: Both intra- and inter-examiner reliability were generally excellent for all parameters obtained by the three methods, except for the dental crowding measured using M1(ICC: 0.473/0.261). The dental crowding measured using M2 were significantly increased in mild, moderate and severe-crowding groups compared with M1. However, no significant difference was detected between M1 and M3 in severe-crowding group (maxilla, p = 0.108 > 0.05; mandible, p = 0.074 > 0.05). With the deterioration of crowding condition, the discrepancy of dental crowding between M1 and M2, or M1 and M3 were significantly decreased (maxilla, M2-M1, mild VS serve, p = 0.003 < 0.05; maxilla, M3-M1, mild VS serve, p = 0.003 < 0.05; mandible, M2-M1, mild VS serve, p = 0.000 < 0.001; mandible, M3-M1, mild VS serve, p = 0.043 < 0.05). CONCLUSION: Dental crowding measured using the novel Bonwill⁃Hawley method was relatively greater than the caliper method, but not exceeding the brass wire method, which wound gradually come close to the brass wire method with the deterioration of crowding condition. CLINICAL RELEVANCE: The Bonwill⁃Hawley method basing on CBCT image proved to be a reliable and acceptable choice for orthodontists to analyze the dental crowding.


Subject(s)
Spiral Cone-Beam Computed Tomography , Humans , Reproducibility of Results , Copper , Zinc , Mandible , Maxilla , Dental Arch/diagnostic imaging , Imaging, Three-Dimensional/methods
14.
Front Bioeng Biotechnol ; 11: 1143575, 2023.
Article in English | MEDLINE | ID: mdl-36937751

ABSTRACT

Objective: To select the most appropriate internal fixation method based on the Pauwels angle, in order to provide a new concept for clinical accurate treatment of femoral neck fractures (FNFs). Methods: FNFs models of Pauwels 30 ° ; 40 ° ; 50 ° ; 60 ° were created respectively. For Pauwels ≤ 50 ° , 1, 2 and 3 Cannulated Compression Screws (CCS) and Porous Tantalum Screws (PTS) were used to fix the fracture for the models. For Pauwels 60 ° , 3CCS and Medial Buttress Plate (MBP) combined with 1, 2 and 3CCS were used to fix the fracture. Based on the results of the finite element (FE) analysis, the biomechanical properties of each model were compared by analyzing and evaluating the following four parameters: maximal stress of the bone (MBS), maximal stress of the implants (MIS), maximal displacement of bone (MBD), interfragmentary motion (IFM). Results: At Pauwels 30 ° , the larger parameters were found in 1CCS, which was 94.8 MPa (MBS), 307.7 MPa (MIS), 0.86 mm (MBD) and 0.36 mm (IFM). In 2CCS group, the parameters were 86.1 MPa (MBS), 254.4 MPa (MIS), 0.73 mm (MBD) and 0.27 mm (IFM), which were similar to those of PTS. At Pauwels 40 ° ; 50 ° , with the increase of the number of used CCS, accordingly, the parameters decreased. Particularly, the MIS (Pauwels 50 ° ) of 1CCS was 1,195.3 MPa, but the other were less than the yield range of the materials. At Pauwels 60 ° , the MBS of 3CCS group was 128.6 Mpa, which had the risk of failure. In 2CCS + MBP group, the parameters were 124.2 MPa (MBS), 602.5 MPa (MIS), 0.75 mm (MBD) and 0.48 mm (IFM), The model stability was significantly enhanced after adding MBP. Conclusion: Pauwels type Ⅰ (< 30 ° ) fractures can reduce the number of CCS, and PTS is an appropriate alternative treatment. For Pauwels type Ⅱ fractures ( 30 ° ∼ 50 ° ), the 3CCS fixation method is still recommended. For Pauwels type Ⅲ fractures (> 50 ° ), it is recommended to add MBP to the medial femoral neck and combine with 2CCS to establish a satisfactory fracture healing environment.

15.
J Transl Med ; 21(1): 225, 2023 03 28.
Article in English | MEDLINE | ID: mdl-36978075

ABSTRACT

BACKGROUND: Chimeric antigen receptor macrophage (CAR-M) therapy is a novel cancer immunotherapy approach that integrates CAR structure and macrophage functions. CAR-M therapy has shown unique and impressive antitumor effects in immunotherapy for solid tumors. However, the polarization state of macrophages can affect the antitumor effect of CAR-M. We hypothesized that the antitumor activity of CAR-Ms may be further improved after inducing M1-type polarization. METHODS: In this report, we constructed a novel HER2-targeting CAR-M, which was composed of humanized anti-HER2 scFv, CD28 hinge region and FcγRI transmembrane domain and intracellular domain. Phagocytosis, tumor-killing capacities, and cytokine release of CAR-Ms were detected with or without M1-polarization pretreatment. Several syngeneic tumor models were used to monitor the in vivo antitumor activity of M1-polarized CAR-Ms. RESULTS: After polarization with LPS combined with interferon-γ in vitro, we found that the phagocytic and tumor-killing capacities of CAR-Ms against target cells were significantly enhanced. The expression of costimulatory molecules and proinflammatory cytokines was also significantly increased after polarization. By establishing several syngeneic tumor models in vivo, we also demonstrated that infusing polarized M1-type CAR-Ms could effectively suppress tumor progression and prolong the survival of tumor-bearing mice with enhanced cytotoxicity. CONCLUSIONS: We demonstrated that our novel CAR-M can effectively eliminate HER2-positive tumor cells both in vitro and in vivo, and M1 polarization significantly enhanced the antitumor ability of CAR-M, resulting in a stronger therapeutic effect in solid cancer immunotherapy.


Subject(s)
Neoplasms , Receptors, Chimeric Antigen , Animals , Mice , Receptors, Chimeric Antigen/metabolism , Neoplasms/therapy , Immunotherapy, Adoptive/methods , Immunotherapy , Cytokines/metabolism , Macrophages/metabolism , Xenograft Model Antitumor Assays , Cell Line, Tumor
17.
ACS Synth Biol ; 12(2): 583-595, 2023 02 17.
Article in English | MEDLINE | ID: mdl-36653175

ABSTRACT

The UAG-based genetic code expansion (GCE) enables site-specific incorporation of noncanonical amino acids (ncAAs) harboring novel chemical functionalities in specific target proteins. However, most GCE studies were done in several whole-genome engineered chassis cells whose hundreds of UAG stop codons were systematically edited to UAA to avoid readthrough in protein synthesis in the presence of GCE. The huge workload of removing all UAG limited the application of GCE in other microbial cell factories (MCF) such as Bacillus subtilis, which has 607 genes ended with UAG among its 4245 coding genes. Although the 257 essential genes count only 6.1% of the genes in B. subtilis, they transcribe 12.2% of the mRNAs and express 52.1% of the proteins under the exponential phase. Here, we engineered a strain named Bs-22 in which all 22 engineerable UAG stop codons in essential genes were edited to UAA via CRISPR/Cas9-mediated multiple-site engineering to minimize the negative effect of GCE on the expression of essential genes. Besides the process of constructing GCE-compatible B. subtilis was systematically optimized. Compared with wild-type B. subtilis (Bs-WT), the fluorescence signal of the eGFP expression could enhance 2.25-fold in Bs-22, and the production of protein tsPurple containing l-(7-hydroxycoumarin-4-yl) ethylglycine (Cou) was increased 2.31-fold in Bs-22. We verified that all purified tsPurple proteins from Bs-22 contained Cou, indicating the excellent fidelity of the strategy. This proof-of-concept study reported efficient overexpression of ncAA-rich proteins in MCF with minimized engineering, shedding new light on solving the trade-off between efficiency and workload.


Subject(s)
Amino Acids , Bacillus subtilis , Amino Acids/genetics , Amino Acids/metabolism , Bacillus subtilis/genetics , Bacillus subtilis/metabolism , Codon, Terminator , Proteins/metabolism , Protein Biosynthesis/genetics
18.
Appl Environ Microbiol ; 88(23): e0161722, 2022 12 13.
Article in English | MEDLINE | ID: mdl-36416555

ABSTRACT

The emergence of antimicrobial resistance is a global health concern and calls for the development of novel antibiotic agents. Antimicrobial peptides seem to be promising candidates due to their diverse sources, mechanisms of action, and physicochemical characteristics, as well as the relatively low emergence of resistance. The incorporation of noncanonical amino acids into antimicrobial peptides could effectively improve their physicochemical and pharmacological diversity. Recently, various antimicrobial peptides variants with improved or novel properties have been produced by the incorporation of single and multiple distinct noncanonical amino acids. In this review, we summarize strategies for the incorporation of noncanonical amino acids into antimicrobial peptides, as well as their features and suitabilities. Recent applications of noncanonical amino acid incorporation into antimicrobial peptides are also presented. Finally, we discuss the related challenges and prospects.


Subject(s)
Amino Acids , Antimicrobial Peptides , Amino Acids/metabolism , Anti-Bacterial Agents/pharmacology
19.
Front Bioeng Biotechnol ; 10: 985688, 2022.
Article in English | MEDLINE | ID: mdl-36185439

ABSTRACT

In recent years, the convolutional neural network (CNN) technique has emerged as an efficient new method for designing porous structure, but a CNN model generally contains a large number of parameters, each of which could influence the predictive ability of the CNN model. Furthermore, there is no consensus on the setting of each parameter in the CNN model. Therefore, the present study aimed to investigate the sensitivity of the parameters in the CNN model for the prediction of the mechanical property of porous structures. 10,500 samples of porous structure were randomly generated, and their effective compressive moduli obtained from finite element analysis were used as the ground truths to construct and train a CNN model. 8,000 of the samples were used to train the CNN model, 2000 samples were used for the cross-validation of the CNN model and the remaining 500 new structures, which did not participate in the CNN training process, were used to test the predictive power of the CNN model. The sensitivity of the number of convolutional layers, the number of convolution kernels, the number of pooling layers, the number of fully connected layers and the optimizer in the CNN model were then investigated. The results showed that the optimizer has the largest influence on the training speed, while the fully connected layer has the least impact on the training speed. Additionally, the pooling layer has the largest impact on the predictive ability while the optimizer has the least impact on the predictive ability. In conclusion, the parameters of the CNN model play an important role in the performance of the CNN model and the parameter sensitivity analysis can help optimize the CNN model to increase the computational efficiency.

20.
Front Microbiol ; 13: 933882, 2022.
Article in English | MEDLINE | ID: mdl-36081794

ABSTRACT

For decades, lignocellulosic biomass has been introduced to the public as the most important raw material for the environmentally and economically sustainable production of high-valued bioproducts by microorganisms. However, due to the strong recalcitrant structure, the lignocellulosic materials have major limitations to obtain fermentable sugars for transformation into value-added products, e.g., bioethanol, biobutanol, biohydrogen, etc. In this review, we analyzed the recent trends in bioenergy production from pretreated lignocellulose, with special attention to the new strategies for overcoming pretreatment barriers. In addition, persistent challenges in developing for low-cost advanced processing technologies are also pointed out, illustrating new approaches to addressing the global energy crisis and climate change caused by the use of fossil fuels. The insights given in this study will enable a better understanding of current processes and facilitate further development on lignocellulosic bioenergy production.

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