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1.
Pathogens ; 13(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38921762

RESUMO

Clostridium perfringens is the main pathogen of chicken necrotic enteritis (NE) causing huge economic losses in the poultry industry. Although dietary secondary bile acid deoxycholic acid (DCA) reduced chicken NE, the accumulation of conjugated tauro-DCA (TDCA) raised concerns regarding DCA efficacy. In this study, we aimed to deconjugate TDCA by bile salt hydrolase (BSH) to increase DCA efficacy against the NE pathogen C. perfringens. Assays were conducted to evaluate the inhibition of C. perfringens growth, hydrogen sulfide (H2S) production, and virulence gene expression by TDCA and DCA. BSH activity and sequence alignment were conducted to select the bsh gene for cloning. The bsh gene from Bifidobacterium longum was PCR-amplified and cloned into plasmids pET-28a (pET-BSH) and pDR111 (pDR-BSH) for expressing the BSH protein in E. coli BL21 and Bacillus subtilis 168 (B-sub-BSH), respectively. His-tag-purified BSH from BL21 cells was evaluated by SDS-PAGE, Coomassie blue staining, and a Western blot (WB) assays. Secretory BSH from B. subtilis was analyzed by a Dot-Blot. B-sub-BSH was evaluated for the inhibition of C. perfringens growth. C. perfringens growth reached 7.8 log10 CFU/mL after 24 h culture. C. perfringens growth was at 8 vs. 7.4, 7.8 vs. 2.6 and 6 vs. 0 log10 CFU/mL in 0.2, 0.5, and 1 mM TDCA vs. DCA, respectively. Compared to TDCA, DCA reduced C. perfringens H2S production and the virulence gene expression of asrA1, netB, colA, and virT. BSH activity was observed in Lactobacillus johnsonii and B. longum under anaerobe but not L. johnsonii under 10% CO2 air. After the sequence alignment of bsh from ten bacteria, bsh from B. longum was selected, cloned into pET-BSH, and sequenced at 951 bp. After pET-BSH was transformed in BL21, BSH expression was assessed around 35 kDa using Coomassie staining and verified for His-tag using WB. After the subcloned bsh and amylase signal peptide sequence was inserted into pDR-BSH, B. subtilis was transformed and named B-sub-BSH. The transformation was evaluated using PCR with B. subtilis around 3 kb and B-sub-BSH around 5 kb. Secretory BSH expressed from B-sub-BSH was determined for His-tag using Dot-Blot. Importantly, C. perfringens growth was reduced greater than 59% log10 CFU/mL in the B-sub-BSH media precultured with 1 vs. 0 mM TDCA. In conclusion, TDCA was less potent than DCA against C. perfringens virulence, and recombinant secretory BSH from B-sub-BSH reduced C. perfringens growth, suggesting a new potential intervention against the pathogen-induced chicken NE.

2.
Org Lett ; 26(25): 5253-5257, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38869448

RESUMO

A ligand-free palladium-catalyzed and norbornadiene-mediated annulation reaction of iodoarenes with methyl 2-haloarenecarboxylates is reported. The sequentially accomplished reaction comprises intermolecular C-H arylation, followed by intramolecular decarboxylative annulation, affording various valuable phenanthrenes. This reaction protocol could be expanded to triphenylene syntheses whereby norbornene was the cocatalyst. Interestingly, the decarboxylation of methyl esters was accomplished via solvent-mediated CMe-O bond cleavages.

3.
MAbs ; 16(1): 2362775, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38899735

RESUMO

Over the past two decades, therapeutic antibodies have emerged as a rapidly expanding domain within the field of biologics. In silico tools that can streamline the process of antibody discovery and optimization are critical to support a pipeline that is growing more numerous and complex every year. High-quality structural information remains critical for the antibody optimization process, but antibody-antigen complex structures are often unavailable and in silico antibody docking methods are still unreliable. In this study, DeepAb, a deep learning model for predicting antibody Fv structure directly from sequence, was used in conjunction with single-point experimental deep mutational scanning (DMS) enrichment data to design 200 potentially optimized variants of an anti-hen egg lysozyme (HEL) antibody. We sought to determine whether DeepAb-designed variants containing combinations of beneficial mutations from the DMS exhibit enhanced thermostability and whether this optimization affected their developability profile. The 200 variants were produced through a robust high-throughput method and tested for thermal and colloidal stability (Tonset, Tm, Tagg), affinity (KD) relative to the parental antibody, and for developability parameters (nonspecific binding, aggregation propensity, self-association). Of the designed clones, 91% and 94% exhibited increased thermal and colloidal stability and affinity, respectively. Of these, 10% showed a significantly increased affinity for HEL (5- to 21-fold increase) and thermostability (>2.5C increase in Tm1), with most clones retaining the favorable developability profile of the parental antibody. Additional in silico tests suggest that these methods would enrich for binding affinity even without first collecting experimental DMS measurements. These data open the possibility of in silico antibody optimization without the need to predict the antibody-antigen interface, which is notoriously difficult in the absence of crystal structures.


Assuntos
Afinidade de Anticorpos , Muramidase , Muramidase/química , Muramidase/imunologia , Muramidase/genética , Estabilidade Proteica , Humanos , Antígenos/imunologia , Antígenos/química , Animais , Simulação por Computador
4.
Front Chem ; 12: 1381835, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915902

RESUMO

Long-chain esters (LCEs) are known to affect aroma perception, but the mechanism of their effects remains unclear. In this study, ethyl palmitate (EP), an important LCE in Osmanthus fragrans flower absolute (OFFA), was selected as a target to identify its role and mechanism. The release characteristics of 10 aroma compounds from OFFA with and without EP were obtained by headspace gas chromatography mass spectrometry (HS-GC/MS) and olfactometry evaluation, respectively. The results show that EP changes the release behaviors of volatile compounds in solution, increases their olfactory detection thresholds (ODTs), and reduces the equilibrium headspace concentrations. According to Whitman's two-film model, EP was found to change the partition coefficients and mass transfer coefficients of the compounds between the liquid and gas phases. This indicates that EP plays an important role in the scent formation of a flavor product and that it is very valuable for the style design of the flavor product.

5.
Genes (Basel) ; 15(6)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38927585

RESUMO

This research focuses on 72 approved varieties of colored wheat from different provinces in China. Utilizing coefficients of variation, structural equation models, and correlation analyses, six agronomic traits of colored wheat were comprehensively evaluated, followed by further research on different dwarfing genes in colored wheat. Using the entropy method revealed that among the 72 colored wheat varieties, 10 were suitable for cultivation. Variety 70 was the top-performing variety, with a comprehensive index of 87.15%. In the final established structural equation model, each agronomic trait exhibited a positive direct effect on yield. Notably, plant height, spike length, and flag leaf width had significant impacts on yield, with path coefficients of 0.55, 0.40, and 0.27. Transcriptome analysis and real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) validation were used to identify three dwarfing genes controlling plant height: Rht1, Rht-D1, and Rht8. Subsequent RT-qPCR validation clustering heatmap results indicated that Rht-D1 gene expression increased with the growth of per-acre yield. Rht8 belongs to the semi-dwarf gene category and has a significant positive effect on grain yield. However, the impact of Rht1, as a dwarfing gene, on agronomic traits varies. These research findings provide crucial references for the breeding of new varieties.


Assuntos
Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , China , Genes de Plantas/genética , Fenótipo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Melhoramento Vegetal/métodos , Característica Quantitativa Herdável , Perfilação da Expressão Gênica/métodos
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124601, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38852307

RESUMO

Heavy metals, including Hg2+, Cr6+ and Cd2+, have always been a major issue in environmental pollution, leading to abnormal changes in the levels of biologically active molecules including Cys in plants, seriously affecting all aspects of the growth and development of plants. This makes it essential to develop a simple and practical method to study the potential impact of heavy metals on plants. In this paper, our research group has developed near-infrared fluorescent probe WRM-S, which has the advantages of fast response, sensitivity to Cys, and successfully applying it to cells and zebrafish. Moreover, it combined the close relationship between heavy metal stress on plants and Cys, using Cys as the detection target, monitoring the internal environment changes of two plants under Hg2+, Cr6+, and Cd2+ stress in the environment, and then conducting 3D imaging. The results indicated that the probe has strong penetration ability in plant tissues, and revealed abnormal changes in plant Cys levels caused by heavy metal stress-induced cellular oxidative stress or cytotoxicity. Thus, the in-situ imaging detection of this probe provides a direction for the physiological dynamics research of plant environmental stress.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38908824

RESUMO

OBJECTIVES: Ceftolozane-tazobactam (C/T) is a combination of a cephalosporin and a ß-lactamase inhibitor with activity against Gram-negative bacilli (GNB). The study aims were to evaluate the activity of C/T in vitro vs. comparators against clinical GNB isolated from Chinese pediatric patients. METHODS: From 2017-2021, 660 GNB isolates were collected from 20 hospitals across China. The minimum inhibitory concentrations were tested using a Trek Diagnostic System (Thermo Fisher Scientific). Susceptibility was determined by CLSI broth microdilution and the results were interpreted according to CLSI M100 (2021) breakpoints. RESULTS: GNB isolates were obtained from pediatric patients < 18 years old, mainly from the bloodstream (n=146), intraperitoneal cavity (n=138), lower respiratory (n=278) and urinary tract (n=96). Overall, C/T was active against 76.6% of 436 Enterobacterales, with a descending susceptibility rate of 100.0% to S. marcescens, 92.2% to E. coli, 83.3% to K. oxytoca, 66.7% to K. aerogenes, 66.7% to P. mirabilis, 58.6% to K. pneumoniae and 57.1% to E. cloacae. The susceptibility of P. aeruginosa to C/T was 89.4%, which was the highest among the ß-lactams and was second only to amikacin (92.9%). Isolates of respiratory tract infection (RTI) derived P. aeruginosa were highly susceptible (93.8%) to C/T, while < 75% of isolates of RTI derived P. aeruginosa were susceptible to the other ß-lactams tested, except for ceftazidime-avibactam (91.2%). CONCLUSION: GNBs collected from pediatric patients in China showed a high susceptibility to C/T making this drug combination an effective choice for treating the pediatric population, especially those infected with P. aeruginosa.

8.
Cancer Lett ; 597: 217070, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880227

RESUMO

The androgen receptor signaling inhibitor (ARSI) enzalutamide (Enz) has shown critical efficacy in the treatment of advanced prostate cancer (PCa). However, the development of drug resistance is a significant factor contributing to mortality in PCa patients. We aimed to explore the key mechanisms of Enz-resistance. Through analysis of GEO databases, we identified SLC4A4 as a novel driver in Enz resistance. Long-term Enz treatment leads to the up-regulation of SLC4A4, which in turn mediates P53 lactylation via the NF-κB/STAT3/SLC4A4 axis, ultimately leading to the development of Enz resistance and progression of PCa. SLC4A4 knockdown overcomes Enz resistance both in vitro and in vivo. Hence, our results suggest that targeting SLC4A4 could be a promising therapeutic strategy for Enz resistance. STATEMENT OF SIGNIFICANCE: SLC4A4 is a novel driver of enzalutamide resistance.

9.
IEEE Trans Image Process ; 33: 3935-3949, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38917291

RESUMO

The ability to detect and track the dynamic objects in different scenes is fundamental to real-world applications, e.g., autonomous driving and robot navigation. However, traditional Multi-Object Tracking (MOT) is limited to track objects belonging to the pre-defined closed-set categories. Recently, Generic MOT (GMOT) is proposed to track interested objects beyond pre-defined categories and it can be divided into Open-Vocabulary MOT (OVMOT) and Template-Image-based MOT (TIMOT). Taking the consideration that the expensive well pre-trained (vision-)language model and fine-grained category annotations are required to train OVMOT models, in this paper, we focus on TIMOT and propose a simple but effective method, Siamese-DETR. Only the commonly used detection datasets (e.g., COCO) are required for training. Different from existing TIMOT methods, which train a Single Object Tracking (SOT) based detector to detect interested objects and then apply a data association based MOT tracker to get the trajectories, we leverage the inherent object queries in DETR variants. Specifically: 1) The multi-scale object queries are designed based on the given template image, which are effective for detecting different scales of objects with the same category as the template image; 2) A dynamic matching training strategy is introduced to train Siamese-DETR on commonly used detection datasets, which takes full advantage of provided annotations; 3) The online tracking pipeline is simplified through a tracking-by-query manner by incorporating the tracked boxes in the previous frame as additional query boxes. The complex data association is replaced with the much simpler Non-Maximum Suppression (NMS). Extensive experimental results show that Siamese-DETR surpasses existing MOT methods on GMOT-40 dataset by a large margin.

10.
Neurol Genet ; 10(3): e200162, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38841628

RESUMO

Background and Objectives: Spinocerebellar ataxia type 3 (SCA3) is a hereditary ataxia that occurs worldwide. Clinical patterns were observed, including the one characterized by marked spastic paraplegia. This study investigated the clinical features, disease progression, and multiparametric imaging aspects of patients with SCA3. Methods: We retrospectively analyzed 249 patients with SCA3 recruited from the Organization for Southeast China for cerebellar ataxia research between October 2014 and December 2020. Of the 249 patients, 145 were selected and assigned to 2 groups based on neurologic examination: SCA3 patients with spastic paraplegia (SCA3-SP) and SCA3 patients with nonspastic paraplegia (SCA3-NSP). Participants underwent 3.0-T brain MRI examinations, and voxel-wise and volume-of-interest-based approaches were used for the resulting images. A tract-based spatial statistical approach was used to investigate the white matter (WM) alterations using diffusion tensor imaging, neurite orientation dispersion, and density imaging metrics. Multiple linear regression analyses were performed to compare the clinical and imaging parameters between the 2 groups. The longitudinal data were evaluated using a linear mixed-effects model. Results: Forty-three patients with SCA3-SP (mean age, 37.58years ± 11.72 [SD]; 18 women) and 102 patients with SCA3-NSP (mean age, 47.42years ± 12.50 [SD]; 39 women) were analyzed. Patients with SCA3-SP were younger and had a lower onset age but a larger cytosine-adenine-guanine repeat number, as well as higher clinical severity scores (all corrected p < 0.05). The estimated progression rates of the Scale for the Assessment and Rating of Ataxia (SARA) and International Cooperative Ataxia Rating Scale scores were higher in the SCA3-SP subgroup than in the SCA3-NSP subgroup (SARA, 2.136 vs 1.218 points; ICARS, 5.576 vs 3.480 points; both p < 0.001). In addition, patients with SCA3-SP showed gray matter volume loss in the precentral gyrus with a decreased neurite density index in the WM of the corticospinal tract and cerebellar peduncles compared with patients with SCA3-NSP. Discussion: SCA3-SP differs from SCA3-NSP in clinical features, multiparametric brain imaging findings, and longitudinal follow-up progression.

11.
Front Neurosci ; 18: 1405734, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855440

RESUMO

Objective: In this work, we propose a novel method for constructing whole-brain spatio-temporal multilayer functional connectivity networks (FCNs) and four innovative rich-club metrics. Methods: Spatio-temporal multilayer FCNs achieve a high-order representation of the spatio-temporal dynamic characteristics of brain networks by combining the sliding time window method with graph theory and hypergraph theory. The four proposed rich-club scales are based on the dynamic changes in rich-club node identity, providing a parameterized description of the topological dynamic characteristics of brain networks from both temporal and spatial perspectives. The proposed method was validated in three independent differential analysis experiments: male-female gender difference analysis, analysis of abnormality in patients with autism spectrum disorders (ASD), and individual difference analysis. Results: The proposed method yielded results consistent with previous relevant studies and revealed some innovative findings. For instance, the dynamic topological characteristics of specific white matter regions effectively reflected individual differences. The increased abnormality in internal functional connectivity within the basal ganglia may be a contributing factor to the occurrence of repetitive or restrictive behaviors in ASD patients. Conclusion: The proposed methodology provides an efficacious approach for constructing whole-brain spatio-temporal multilayer FCNs and conducting analysis of their dynamic topological structures. The dynamic topological characteristics of spatio-temporal multilayer FCNs may offer new insights into physiological variations and pathological abnormalities in neuroscience.

12.
BMC Med Educ ; 24(1): 651, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862950

RESUMO

OBJECTIVE: Currently, there are still some shortcomings in EBM education in China.The study aimed to investigate the effectiveness of the novel evidence-based medicine (EBM) learning model of "autonomy-collaboration." METHODS: A total of 91 undergraduate students majoring in clinical medicine at Zhongshan Clinical College of Dalian University from the 2019 batch were selected as the participants in this study. They were instructed to follow the EBM learning model of "autonomy-collaboration." Upon completion of the course, questionnaires, records of participants' sentiments and insights, and evidence-based clinical practice reports were used as indicators to evaluate the effectiveness of the training. RESULTS: This learning modality effectively enhanced independent learning ability of the students, stimulated their interest in learning, and strengthened the communication between students and teachers, thereby improving the quality of teaching. CONCLUSION: The novel EBM learning model of "autonomy-collaboration," exhibited robust effectiveness in instruction and facilitated the seamless integration of theoretical knowledge with clinical practice. Consequently, its widespread adoption is strongly recommended.


Assuntos
Educação de Graduação em Medicina , Medicina Baseada em Evidências , Estudantes de Medicina , Humanos , Medicina Baseada em Evidências/educação , Educação de Graduação em Medicina/métodos , China , Aprendizagem , Modelos Educacionais , Comportamento Cooperativo , Feminino , Masculino , Inquéritos e Questionários , Avaliação Educacional
13.
Microbiol Spectr ; : e0008624, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916336

RESUMO

Acinetobacter baumannii is one of the most important pathogens worldwide. The intrinsic and acquired resistance of A. baumannii, coupled with the slow pace of novel antimicrobial drug development, poses an unprecedented and enormous challenge to clinical anti-infective therapy of A. baumannii. Recent studies in the field of pathogenicity, antibiotic resistance, and biofilms of A. baumannii have focused on the model strains, including ATCC 17978, ATCC 19606, and AB5075. However, these model strains represent only a limited portion of the heterogeneity in A. baumannii. Furthermore, variants of these model strains have emerged that show significant diversity not only at the genotypic level but also reflected in differences at the phenotypic levels of capsule, virulence, pathogenicity, and antibiotic resistance. Research on A. baumannii, a key pathogen, would benefit from a standardized approach, which characterizes heterogeneous strains in order to facilitate rapid diagnosis, discovery of new therapeutic targets, and efficacy assessment. Our study provides and describes a standardized, genomically and phenotypically heterogeneous panel of 45 different A. baumannii strains for the research community. In addition, we performed comparative analyses of several phenotypes of this panel. We found that the sequence type 2 (ST2) group showed significantly higher rates of resistance, lower fitness cost for adaptation, and yet less biofilm formation. The Macrocolony type E (MTE, flat center and wavy edge phenotype reported in the literature) group showed a less clear correlation of resistance rates and growth rate, but was observed to produce more biofilms. Our study sheds light on the complex interplay of resistance fitness and biofilm formation within distinct strains, offering insights crucial for combating A. baumannii infection. IMPORTANCE: Acinetobacter baumannii is globally notorious, and in an effort to combat the spread of such pathogens, several emerging candidate therapies have already surfaced. However, the strains used to test these therapies vary across studies (the sources and numbers of test strains are varied and often very large, with little heterogeneity). The variation complicates the studies. Furthermore, the limited standardized resources of A. baumannii strains have greatly restricted the research on the physiology, pathogenicity, and antibiotic resistance. Therefore, it is crucial for the research community to acquire a standardized and heterogeneous panel of A. baumannii. Our study meticulously selected 45 diverse A. baumannii strains from a total of 2,197 clinical isolates collected from 64 different hospitals across 27 provinces in China, providing a scientific reference for the research community. This assistance will significantly facilitate scientific exchange in academic research.

14.
Nat Prod Res ; : 1-9, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824431

RESUMO

A novel cytochalasin named diaporchalasin A (1) bearing a cinnamenyl and an epoxy-macrocycloketone, and a new benzenepropionic acid derivative (2), and two known compounds (3 and 4) were isolated from Conus marmoreus-derived fungus Diaporthe sp. XMA007. Their structures were elucidated through detailed spectroscopic analysis, and the absolute configuration of 1 was determined by conformational analysis and TDDFT-ECD calculation. Their activity evaluation on PDE4 inhibition and breast cancer cell cytotoxicity were conducted, and compound 1 showed moderate inhibition on PDE4.

15.
Cell Death Differ ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871948

RESUMO

Hepatic stellate cells (HSCs) secrete extracellular matrix for collagen deposition, contributing to liver fibrosis. Ferroptosis is a novel type of programmed cell death induced by iron overload-dependent lipid peroxidation. Regulation of ferroptosis in hepatic stellate cells (HSCs) may have therapeutic potential for liver fibrosis. Here, we found that Maf bZIP transcription factor G (MafG) was upregulated in human and murine liver fibrosis. Interestingly, MafG knockdown increased HSCs ferroptosis, while MafG overexpression conferred resistance of HSCs to ferroptosis. Mechanistically, MafG physically interacted with non-muscle myosin heavy chain IIa (MYH9) to transcriptionally activate lipocalin 2 (LCN2) expression, a known suppressor for ferroptosis. Site-directed mutations of MARE motif blocked the binding of MafG to LCN2 promoter. Re-expression of LCN2 in MafG knockdown HSCs restored resistance to ferroptosis. In bile duct ligation (BDL)-induced mice model, we found that treatment with erastin alleviated murine liver fibrosis by inducing HSC ferroptosis. HSC-specific knowdown MafG based on adeno-associated virus 6 (AAV-6) improved erastin-induced HSC ferroptosis and alleviation of liver fibrosis. Taken together, MafG inhibited HSCs ferroptosis to promote liver fibrosis through transcriptionally activating LCN2 expression. These results suggest that MafG/MYH9-LCN2 signaling pathway could be a novel targets for the treatment of liver fibrosis.

16.
Nat Commun ; 15(1): 5130, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879536

RESUMO

Intron retention (IR) is the most common alternative splicing event in Arabidopsis. An increasing number of studies have demonstrated the major role of IR in gene expression regulation. The impacts of IR on plant growth and development and response to environments remain underexplored. Here, we found that IR functions directly in gene expression regulation on a genome-wide scale through the detainment of intron-retained transcripts (IRTs) in the nucleus. Nuclear-retained IRTs can be kept away from translation through this mechanism. COP1-dependent light modulation of the IRTs of light signaling genes, such as PIF4, RVE1, and ABA3, contribute to seedling morphological development in response to changing light conditions. Furthermore, light-induced IR changes are under the control of the spliceosome, and in part through COP1-dependent ubiquitination and degradation of DCS1, a plant-specific spliceosomal component. Our data suggest that light regulates the activity of the spliceosome and the consequent IRT nucleus detainment to modulate photomorphogenesis through COP1.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Núcleo Celular , Regulação da Expressão Gênica de Plantas , Íntrons , Luz , Spliceossomos , Ubiquitina-Proteína Ligases , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos da radiação , Arabidopsis/metabolismo , Íntrons/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Spliceossomos/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Núcleo Celular/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/genética , Plântula/efeitos da radiação , Plântula/metabolismo , Processamento Alternativo , Ubiquitinação
17.
Environ Sci Technol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900106

RESUMO

Appropriate mixed carbon sources have great potential to enhance denitrification efficiency and reduce operational costs in municipal wastewater treatment plants (WWTPs). However, traditional methods struggle to efficiently select the optimal mixture due to the variety of compositions. Herein, we developed a machine learning-assisted high-throughput method enabling WWTPs to rapidly identify and optimize mixed carbon sources. Taking a local WWTP as an example, a mixed carbon source denitrification data set was established via a high-throughput method and employed to train a machine learning model. The composition of carbon sources and the types of inoculated sludge served as input variables. The XGBoost algorithm was employed to predict the total nitrogen removal rate and microbial growth, thereby aiding in the assessment of the denitrification potential. The predicted carbon sources exhibited an enhanced denitrification potential over single carbon sources in both kinetic experiments and long-term reactor operations. Model feature analysis shows that the cumulative effect and interaction among individual carbon sources in a mixture significantly enhance the overall denitrification potential. Metagenomic analysis reveals that the mixed carbon sources increased the diversity and complexity of denitrifying bacterial ecological networks in WWTPs. This work offers an efficient method for WWTPs to optimize mixed carbon source compositions and provides new insights into the mechanism behind enhanced denitrification under a supply of multiple carbon sources.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124474, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-38763018

RESUMO

In recent years, aggregation-induced emission luminogens (AIEgens) have witnessed numerous groundbreaking advances in fundamental theoretical research and functional applications. Notably, stimuli-responsive AIEgens have achieved remarkable results, demonstrating immense potential for application in various fields such as chemistry, materials science, biology, and medicine. Herein, two multi-stimuli-responsive cyanostilbene derivatives TPE-CNTPA and PH-CNTPA were synthesized by introducing tetraphenylethylene (TPE) and trifluoromethyl groups, respectively. Primarily, under the combined mechanism of aggregation-induced emission (AIE) and twisted intramolecular charge transfer (TICT), TPE-CNTPA and PH-CNTPA exhibit "on-off-on" fluorescent emission characteristics in solution. Secondly, under 365 nm ultraviolet light irradiation, the photo-induced isomerization of PH-CNTPA causes changes in photophysical property, demonstrating its responsiveness to ultraviolet light. In addition, TPE-CNTPA and PH-CNTPA exhibit high-contrast mechanochromic properties, providing broader possibilities for their potential applications in various fields. Moreover, owing to the unique fluorescence emission characteristics, TPE-CNTPA and PH-CNTP have enormous potential for application in the field of encryption anti-counterfeiting. Besides, PH-CNTPA can be utilized for the detection of trace water in single or mixed solvents, demonstrating outstanding sensitivity and anti-interference properties in different solvents. This research work reveals the potential in the fields of water sensing and anti-counterfeiting for these two multi-stimuli-responsive compounds.

19.
Int J Biol Macromol ; 270(Pt 1): 132344, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754666

RESUMO

Hydroxypropyl-gamma-cyclodextrin (HPγCD) inclusion complex nanofibers (Lut/HPγCD-IC-NF) containing Luteolin (Lut) were prepared by electrospinning technology. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) spectra confirmed the formation of Lut/HPγCD-IC-NF. Scanning electron microscopy (SEM) images showed that the morphology of Lut/HPγCD-IC-NF was uniform and bead-free, suggesting that self-assembled aggregates, macromolecules with higher molecular weights, were formed by strong hydrogen bonding interactions between the cyclodextrin inclusion complexes. Confocal laser scanning microscopy (CLSM) images showed that Lut was distributed in Lut/HPγCD-IC-NF. Proton nuclear magnetic resonance (1H NMR) spectroscopy revealed the change in chemical shift of the proton peak between Lut and HPγCD, confirming the formation of inclusion complex. Thermogravimetric analysis (TGA) proved that Lut/HPγCD-IC-NF had good thermal stability. The phase solubility test confirmed that HPγCD had a solubilizing effect on Lut. When the solubility of HPγCD reached 10 mM, the solubility of Lut increased by 15-fold. The drug loading test showed that the content of Lut in fibers reached 8.57 ± 0.02 %. The rapid dissolution experiment showed that Lut/HPγCD-IC-NF dissolved within 3 s. The molecular simulation provides three-dimensional evidence for the formation of inclusion complexes between Lut and HPγCD. Antibacterial experiments showed that Lut/HPγCD-IC-NF had enhanced antibacterial activity against S. aureus. Lut/HPγCD-IC-NF exhibited excellent antioxidant properties with a free radical scavenging ability of 89.5 ± 1.1 %. In vitro release experiments showed Lut/HPγCD-IC-NF had a higher release amount of Lut. In conclusion, Lut/HPγCD-IC-NF improved the physicochemical properties and bioavailability of Lut, providing potential applications of Lut in the pharmaceutical field.


Assuntos
Luteolina , Nanofibras , gama-Ciclodextrinas , Nanofibras/química , gama-Ciclodextrinas/química , Luteolina/química , Luteolina/farmacologia , Solubilidade , Antibacterianos/farmacologia , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Picratos/química , Compostos de Bifenilo/química
20.
J Neurol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771386

RESUMO

BACKGROUND: To investigate Ranvier's autoantibodies prevalence and isotypes in various peripheral neuropathy variants, compare clinical features between seronegative and seropositive patients, and elucidate immune mechanisms underlying antibody generation. METHODS: Antibodies against anti-neurofascin-155 (NF155), NF186, contactin-1 (CNTN1), CNTN2, contactin-associated protein 1 (CASPR1), and CASPR2 were identified through cell-based assays. Plasma cytokines were analyzed in anti-NF155 antibody-positive chronic inflammatory demyelinating polyneuropathy (NF155+ CIDP) and Ranvier's antibodies-negative CIDP (Ab- CIDP) patients using a multiplexed fluorescent immunoassay, validated in vitro in a cell culture model. RESULTS: In 368 plasma samples, 50 Ranvier's autoantibodies were found in 45 individuals, primarily in CIDP cases (25 out of 69 patients) and in 10 out of 122 Guillain-Barré syndrome patients. Anti-NF155 and CNTN1-IgG were exclusive to CIDP. Fourteen samples were NF155-IgG, primarily IgG4 subclass, linked to CIDP features including early onset, tremor, sensory disturbance, elevated CSF protein, prolonged motor latency, conduction block, and poor treatment response. NF155-IgG had low sensitivity (20.28%) but high specificity (100%) for CIDP, rising to 88.88% with tremor and prolonged motor latency. Cytokine profiling in NF155+ CIDP revealed distinct immune responses involving helper T cells, toll-like receptor pathways. Some NF155+ CIDP patients had circulating NF155-specific B cells producing NF155-IgG without antigen presence, suggesting therapeutic potential. CONCLUSION: The study emphasizes the high specificity and sensitivity of NF155-IgG for diagnosing CIDP characterized by distinctive features. Further investigation into circulating NF155-specific B cell phenotypes may pave the way for B cell directed therapy.

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