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1.
Hepatology ; 77(3): 965-981, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35938354

RESUMO

BACKGROUND AND AIMS: Chronic HBV infection is the leading cause of HCC and a serious health problem in China, East Asia, and North African countries. Effective treatment of HBV-related HCC is currently unavailable. This study evaluated the therapeutic potential of T-cell immunoreceptor with Ig and ITIM domains (TIGIT) blockade in HBV-related HCC. APPROACH AND RESULTS: A mouse model of spontaneous HBV-related HCC was generated by replacing wild-type hepatocytes with HBsAg + hepatocytes (namely HBs-HepR mice). The tumors in HBs-HepR mice were inflammation-associated HCC, similar to HBV-related HCC in patients, which was distinguished from other HCC mouse models, such as diethylnitrosamine-induced HCC, TGF-ß-activated kinase 1 knockout-induced HCC, HCC in a stelic animal model, or NASH-induced HCC. HCC in HBs-HepR mice was characterized by an increased number of CD8 + T cells, whereas the production of IL-2, TNF-α, and interferon-gamma (IFN-γ) by intrahepatic CD8 + T cells was decreased. Increased expression of TIGIT on CD8 + T cells was responsible for functional exhaustion. The therapeutic effect of TIGIT blockade was investigated at the early and middle stages of HCC progression in HBs-HepR mice. TIGIT blockade reinvigorated intrahepatic CD8 + T cells with increased TNF-α and IFN-γ production and an increased number of CD8 + T cells in tumors, thereby slowing the development of HCC in HBs-HepR mice. Blocking PD-L1 did not show direct therapeutic effects or synergize with TIGIT blockade. CONCLUSIONS: Blockade of TIGIT alone enhanced the antitumor activity of CD8 + T cells during the progression of HBV-related HCC in a spontaneous HCC mouse model.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Linfócitos T CD8-Positivos , Vírus da Hepatite B , Neoplasias Hepáticas/patologia , Receptor de Morte Celular Programada 1 , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Imunoglobulinas/imunologia
2.
Cancer Cell Int ; 24(1): 12, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184549

RESUMO

BACKGROUND: Glycolysis is critical for harvesting abundant energy to maintain the tumor microenvironment in malignant tumors. Retinoic acid-related orphan receptor α (RORα) has been identified as a circadian gene. However, the association of glycolysis with RORα in regulating gastric cancer (GC) proliferation remains poorly understood. METHODS: Bioinformatic analysis and retrospective study were utilized to explore the role of RORα in cell cycle and glycolysis in GC. The mechanisms were performed in vitro and in vivo including colony formation, Cell Counting Kit-8 (CCK-8), Epithelial- mesenchymal transition (EMT) and subcutaneous tumors of mice model assays. The key drives between RORα and glycolysis were verified through western blot and chip assays. Moreover, we constructed models of high proliferation and high glucose environments to verify a negative feedback and chemoresistance through a series of functional experiments in vitro and in vivo. RESULTS: RORα was found to be involved in the cell cycle and glycolysis through a gene set enrichment analysis (GSEA) algorithm. GC patients with low RORα expression were not only associated with high circulating tumor cells (CTC) and high vascular endothelial growth factor (VEGF) levels. However, it also presented a positive correlation with the standard uptake value (SUV) level. Moreover, the SUVmax levels showed a positive linear relation with CTC and VEGF levels. In addition, RORα expression levels were associated with glucose 6 phosphate dehydrogenase (G6PD) and phosphofructokinase-2/fructose-2,6-bisphosphatase (PFKFB3) expression levels, and GC patients with low RORα and high G6PD or low RORα and high PFKFB3 expression patterns had poorest disease-free survival (DFS). Functionally, RORα deletion promoted GC proliferation and drove glycolysis in vitro and in vivo. These phenomena were reversed by the RORα activator SR1078. Moreover, RORα deletion promoted GC proliferation through attenuating G6PD and PFKFB3 induced glycolytic activity in vitro and in vivo. Mechanistically, RORα was recruited to the G6PD and PFKFB3 promoters to modulate their transcription. Next, high proliferation and high glucose inhibited RORα expression, which indicated that negative feedback exists in GC. Moreover, RORα deletion improved fluorouracil chemoresistance through inhibition of glucose uptake. CONCLUSION: RORα might be a novel biomarker and therapeutic target for GC through attenuating glycolysis.

3.
J Fluoresc ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193952

RESUMO

Fluorescence intensity and selective recognition ability are crucial factors in determining the analytical techniques for fluorescent probes. In this study, a core-shell fluorescent material, composed of silver nanoparticles@nitrogen-doped graphene quantum dots (Ag NPs@N/GQDs), was synthesised using mango leaves as the raw material through a thermal cracking method, resulting in strong fluorescence luminescence intensity. By employing noradrenaline as a template molecule and using a surface molecular imprinting technique, a molecularly imprinted membrane (MIP) was formed on the surface of the fluorescent material, that was subsequently eluted to obtain a highly specific, fluorescent probe capable of recognising noradrenaline. The probe captured various concentrations of noradrenaline using the MIP, which decreased the fluorescence intensity. Then a method for detecting trace amounts of noradrenaline was established. This method exhibited a linear range from 0.5 -700 pM with a detection limit of 0.154 pM. The proposed method was implemented in banana samples. Satisfactory recoveries were confirmed at four different concentrations. The method presented a relative standard deviation (RSD) of less than 5.0%.

4.
Nature ; 557(7704): 177-182, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29720658

RESUMO

Loss of dopamine in Parkinson's disease is hypothesized to impede movement by inducing hypo- and hyperactivity in striatal spiny projection neurons (SPNs) of the direct (dSPNs) and indirect (iSPNs) pathways in the basal ganglia, respectively. The opposite imbalance might underlie hyperkinetic abnormalities, such as dyskinesia caused by treatment of Parkinson's disease with the dopamine precursor L-DOPA. Here we monitored thousands of SPNs in behaving mice, before and after dopamine depletion and during L-DOPA-induced dyskinesia. Normally, intermingled clusters of dSPNs and iSPNs coactivated before movement. Dopamine depletion unbalanced SPN activity rates and disrupted the movement-encoding iSPN clusters. Matching their clinical efficacy, L-DOPA or agonism of the D2 dopamine receptor reversed these abnormalities more effectively than agonism of the D1 dopamine receptor. The opposite pathophysiology arose in L-DOPA-induced dyskinesia, during which iSPNs showed hypoactivity and dSPNs showed unclustered hyperactivity. Therefore, both the spatiotemporal profiles and rates of SPN activity appear crucial to striatal function, and next-generation treatments for basal ganglia disorders should target both facets of striatal activity.


Assuntos
Dopamina/metabolismo , Discinesias/patologia , Discinesias/fisiopatologia , Neurônios/metabolismo , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/fisiopatologia , Animais , Sinalização do Cálcio , Dopamina/deficiência , Discinesias/etiologia , Discinesias/metabolismo , Feminino , Levodopa/metabolismo , Levodopa/farmacologia , Masculino , Camundongos , Modelos Biológicos , Movimento/efeitos dos fármacos , Neostriado/metabolismo , Neostriado/patologia , Neostriado/fisiopatologia , Transtornos Parkinsonianos/metabolismo , Receptores de Dopamina D1/agonistas , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/metabolismo
5.
Environ Res ; 252(Pt 1): 118779, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38552825

RESUMO

Numerous application of pyrethroid insecticides has led to their accumulation in the environment, threatening ecological environment and human health. Its fate in the presence of iron-bearing minerals and natural organic matter under light irradiation is still unknown. We found that goethite (Gt) and humic acid (HA) could improve the photodegradation of bifenthrin (BF) in proper concentration under light irradiation. The interaction between Gt and HA may further enhance BF degradation. On one hand, the adsorption of HA on Gt may decrease the photocatalytic activity of HA through decreasing HA content in solution and sequestering the functional groups related with the production of reactive species. On the other hand, HA could improve the photocatalytic activity of Gt through extending light absorption, lowing of bandgap energy, hindering the recombination of photo-generated charges, and promoting the oxidation and reduction reaction on Gt surface. The increased oxygen vacancies on Gt surface along with the reduction of trivalent iron and the nucleophilic attack of hole to surface hydroxyl group contributed to the increasing photocatalytic activity of Gt. Electron paramagnetic resonance and quenching studies demonstrated that both oxidation species, such as hydroxyl radical (•OH) and singlet oxygen (1O2), and reducing species, such as hydrogen atoms (H•) and superoxide anion radical (O2•-), contributed to BF degradation in UV-Gt-HA system. Mass spectrometry, ion chromatography, and toxicity assessment indicated that less toxic C23H22ClF3O3 (OH-BF), C9H10ClF3O (TFP), C14H14O2 (OH-MBP), C14H12O2 (MBP acid), C14H12O3 (OH-MBP acid), and chloride ions were the main degradation products. The production of OH-BF, MPB, and TFP acid through oxidation and the production of MPB and TFP via reduction were the two primary pathways of BF degradation.


Assuntos
Substâncias Húmicas , Compostos de Ferro , Minerais , Oxirredução , Piretrinas , Substâncias Húmicas/análise , Minerais/química , Compostos de Ferro/química , Piretrinas/química , Fotólise , Inseticidas/química
6.
Int J Mol Sci ; 25(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38928293

RESUMO

Zr-50Ti alloys are promising biomaterials due to their excellent mechanical properties and low magnetic susceptibility. However, Zr-50Ti alloys do not inherently bond well with bone. This study aims to enhance the bioactivity and bonding strength of Zr-50Ti alloys for orthopedic implant materials. Initially, the surface of Zr-50Ti alloys was treated with a sulfuric acid solution to create a microporous structure, increasing surface roughness and area. Subsequently, low crystalline calcium phosphate (L-CaP) precipitation was controlled by adding Mg2+ and/or CO32- ions in modified simulated body fluid (m-SBF). The treated Zr-50Ti alloys were then subjected to cold isostatic pressing to force m-SBF into the micropores, followed by incubation to allow L-CaP formation. The apatite-forming process was tested in simulated body fluid (SBF). The results demonstrated that the incorporation of Mg2+ and/or CO32- ions enabled the L-CaP to cover the entire surface of Zr-50Ti alloys within only one day. After short-term soaking in SBF, the L-CaP layer, modulated by Mg2+ and/or CO32- ions, formed a uniform hydroxyapatite (HA) coating on the surface of the Zr-50Ti alloys, showing potential for optimized bone integration. After soaking in SBF for 14 days, the bonding strength between the apatite layer and alloy has the potential to meet the orthopedic application requirement of 22 MPa. This study demonstrates an effective method to enhance the bioactivity and bonding strength of Zr-50Ti alloys for orthopedic applications.


Assuntos
Ligas , Líquidos Corporais , Fosfatos de Cálcio , Propriedades de Superfície , Zircônio , Ligas/química , Zircônio/química , Líquidos Corporais/química , Fosfatos de Cálcio/química , Titânio/química , Materiais Biocompatíveis/química , Teste de Materiais , Magnésio/química , Durapatita/química
7.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396732

RESUMO

Phosphoenolpyruvate carboxylase (PEPC) gene family plays a crucial role in both plant growth and response to abiotic stress. Approximately half of the Orchidaceae species are estimated to perform CAM pathway, and the availability of sequenced orchid genomes makes them ideal subjects for investigating the PEPC gene family in CAM plants. In this study, a total of 33 PEPC genes were identified across 15 orchids. Specifically, one PEPC gene was found in Cymbidium goeringii and Platanthera guangdongensis; two in Apostasia shenzhenica, Dendrobium chrysotoxum, D. huoshanense, Gastrodia elata, G. menghaiensis, Phalaenopsis aphrodite, Ph. equestris, and Pl. zijinensis; three in C. ensifolium, C. sinense, D. catenatum, D. nobile, and Vanilla planifolia. These PEPC genes were categorized into four subgroups, namely PEPC-i, PEPC-ii, and PEPC-iii (PTPC), and PEPC-iv (BTPC), supported by the comprehensive analyses of their physicochemical properties, motif, and gene structures. Remarkably, PEPC-iv contained a heretofore unreported orchid PEPC gene, identified as VpPEPC4. Differences in the number of PEPC homolog genes among these species were attributed to segmental duplication, whole-genome duplication (WGD), or gene loss events. Cis-elements identified in promoter regions were predominantly associated with light responsiveness, and circadian-related elements were observed in each PEPC-i and PEPC-ii gene. The expression levels of recruited BTPC, VpPEPC4, exhibited a lower expression level than other VpPEPCs in the tested tissues. The expression analyses and RT-qPCR results revealed diverse expression patterns in orchid PEPC genes. Duplicated genes exhibited distinct expression patterns, suggesting functional divergence. This study offered a comprehensive analysis to unveil the evolution and function of PEPC genes in Orchidaceae.


Assuntos
Orchidaceae , Fosfoenolpiruvato Carboxilase , Humanos , Fosfoenolpiruvato Carboxilase/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Orchidaceae/genética , Orchidaceae/metabolismo , Plantas/metabolismo , Sequência de Bases , Filogenia
8.
Int J Mol Sci ; 25(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38473912

RESUMO

Bulbophyllum is one of the largest genera and presents some of the most intricate taxonomic problems in the family Orchidaceae, including species of ornamental and medical importance. The lack of knowledge regarding the characterization of Bulbophyllum chloroplast (cp) genomes has imposed current limitations on our study. Here, we report the complete cp genomes of seven Bulbophyllum species, including B. ambrosia, B. crassipes, B. farreri, B. hamatum, B. shanicum, B. triste, and B. violaceolabellum, and compared with related taxa to provide a better understanding of their genomic information on taxonomy and phylogeny. A total of 28 Bulbophyllum cp genomes exhibit typical quadripartite structures with lengths ranging from 145,092 bp to 165,812 bp and a GC content of 36.60% to 38.04%. Each genome contained 125-132 genes, encompassing 74-86 protein-coding genes, 38 tRNA genes, and eight rRNA genes. The genome arrangements, gene contents, and length were similar, with differences observed in ndh gene composition. It is worth noting that there were exogenous fragment insertions in the IR regions of B. crassipes. A total of 18-49 long repeats and 38-80 simple sequence repeats (SSRs) were detected and the single nucleotide (A/T) was dominant in Bulbophyllum cp genomes, with an obvious A/T preference. An analysis of relative synonymous codon usage (RSCU) revealed that leucine (Leu) was the most frequently used codon, while cysteine (Cys) was the least used. Six highly variable regions (rpl32-trnLUAG > trnTUGU-trnLUAA > trnFGAA-ndhJ > rps15-ycf1 > rbcL-accD > psbI-trnSGCU) and five coding sequences (ycf1 > rps12 > matK > psbK > rps15) were identified as potential DNA markers based on nucleotide diversity. Additionally, 31,641 molecular diagnostic characters (MDCs) were identified in complete cp genomes. A phylogenetic analysis based on the complete cp genome sequences and 68 protein-coding genes strongly supported that 28 Bulbophyllum species can be divided into four branches, sects. Brachyantha, Cirrhopetalum, and Leopardinae, defined by morphology, were non-monophyly. Our results enriched the genetic resources of Bulbophyllum, providing valuable information to illustrate the complicated taxonomy, phylogeny, and evolution process of the genus.


Assuntos
Genoma de Cloroplastos , Orchidaceae , Filogenia , Orchidaceae/genética , Evolução Molecular , Nucleotídeos
9.
Int Nurs Rev ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967088

RESUMO

AIM: This study aims to investigate the status of academic support perception among nursing interns and explore the correlation between academic support perception, emotional intelligence, and bullying behaviors in nursing education, especially the moderating role of bullying behavior on the relationship between emotional intelligence and academic support perception. BACKGROUND: Academic support perception is closely related to the nursing interns' mental health and academic performance. To some extent, it can reflect nursing interns' satisfaction and happiness during their internship, affecting their motivation to continue their studies. However, little is known about the nursing interns' academic support perception in China. METHODS: A total of 1020 nursing interns participated in this study. A sociodemographic information questionnaire, Bullying Behaviors in Nursing Education Scale, Wong and Law's Emotional Intelligence Scale, and Academic Support in the Practicum Scale were used to collect data. FINDINGS: Bullying behaviors and emotional intelligence were significantly associated with nursing interns' academic support perception. In addition, bullying behaviors in nursing education moderated the association between emotional intelligence and academic support perception. DISCUSSION: Nursing interns who possess high emotional intelligence and experience less bullying in nursing education tend to perceive higher academic support in clinical practice. The positive effects of emotional intelligence on nursing interns' academic support perceptions are contingent on the level of bullying behavior experienced in nursing education. Less bullying behaviors in nursing education enhance the impact of emotional intelligence on academic support perception. CONCLUSION AND IMPLICATIONS FOR NURSING: Strategies should be created to promote emotional intelligence and decrease bullying behaviors in nursing education to improve the perception of academic support among nursing interns.

10.
Funct Integr Genomics ; 23(4): 343, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37991591

RESUMO

Emerging evidence indicates that the interactions and dynamic changes among tumor-associated macrophages (TAMs) are pivotal in molding the tumor microenvironment (TME), thereby influencing diverse clinical outcomes. However, the potential clinical ramifications of these evolutionary shifts in tumor-associated macrophages within pancreatic adenocarcinoma (PAAD) remain largely unexamined. Single-cell RNA sequencing (scRNA-seq) data were retrieved from the Tumor Immune Single-cell Hub. The Seurat and Monocle algorithms were employed to elucidate the progression of TAMs, using non-negative matrix factorization (NMF) to determine molecular classifications. Subsequently, the prognosis, biological characteristics, genomic modifications, and immune landscape across various clusters were interpreted. Furthermore, the sensitivity of potential therapeutic drugs between subtypes was predicted. Cellular experiments were conducted to explore the function of the NR1H3 gene in pancreatic cancer. These experiments encompassed gene knockdown, proliferation assessment, clone formation evaluation, transwell examination, and apoptosis analysis. Trajectory gene expression analysis of tumor-associated macrophages identified three disparate clusters, each associated with different clinical outcomes Compared to clusters C1 and C2, cluster C3 is seemingly at a less advanced pathological stage and associates with a relatively favorable prognosis. Further investigation revealed pronounced genetic instability in cluster C2, whereas cluster C3 demonstrated notable genetic stability. Cluster C1, characterized as "immune-hot," exhibits an abundance of immune cells and elevated immune checkpoint expression, suggesting its suitability for immunotherapy. Furthermore, several potential therapeutic agents have been pinpointed, potentially facilitating the clinical application of these insights. Cell assays indicated that NR1H3 knockdown markedly induced apoptosis and suppressed clonogenesis, migration, and proliferation of pancreatic cancer cells in the PTAU-8988 and PANC-1 cell lines. Overall, our study discerned three clusters with unique characteristics, defined by the evolution of TAMs. We propose customized therapeutic strategies for patients within these specific clusters to improve clinical outcomes and optimize clinical management.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Macrófagos Associados a Tumor , Apoptose/genética , Microambiente Tumoral , Neoplasias Pancreáticas
11.
Cerebellum ; 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37962773

RESUMO

The cerebellum plays an important role in maintaining balance, posture control, muscle tone, and lower limb coordination in healthy individuals and stroke patients. At the same time, the relationship between cerebellum and motor learning has been widely concerned in recent years. Due to the relatively intact structure preservation and high plasticity after supratentorial stroke, non-invasive neuromodulation targeting the cerebellum is increasingly used to treat abnormal gait in stroke patients. The gamma frequency of transcranial alternating current stimulation (tACS) is commonly used to improve motor learning. It is an essential endogenous EEG oscillation in the gamma range during the swing phase, and rhythmic movement changes in the gait cycle. However, the effect of cerebellar tACS in the gamma frequency band on balance and walking after stroke remains unknown and requires further investigation.

12.
Cerebellum ; 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204664

RESUMO

The cerebellum is known to play a supportive role in swallowing-related functions; however, wide discrepancies about the incidence rate of swallowing disorders following cerebellar strokes exist within the literature. This study aimed to investigate the incidence rate of dysphagia and the factors which may affect the presence of dysphagia and clinical recovery in individuals diagnosed with cerebellar stroke. A retrospective chart audit of 1651 post-stroke patients (1049 males and 602 females) admitted with a cerebellar stroke to a comprehensive tertiary hospital in China was conducted. Data on demographics, medical, along with swallowing function assessment were collected. Differences between dysphagic and non-dysphagic groups were evaluated using t-tests and Pearson's chi-square test. Univariate logistic regression analysis was performed to establish factors associated with the presence of dysphagia. A total of 11.45% of participants were identified with dysphagia during inpatient admission. Individuals with mixed types of stroke, multiple lesions in the cerebellum, and ages older than 85 years old were more likely to develop dysphagia. Moreover, the prognosis of dysphagia following a cerebellar stroke was associated with lesions in different parts of the cerebellum. The cumulative recovery rates from the best to worse were the right hemisphere group, the cerebellum vermis or peduncle group, and both the hemisphere group and the left hemisphere group, respectively.

13.
Neural Plast ; 2023: 9532713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37789954

RESUMO

Stroke is a disease with high morbidity and disability, and motor impairment is a common sequela of stroke. Transcutaneous auricular vagus nerve stimulation (taVNS) is a type of non-invasive stimulation, which can effectively improve post-stroke motor dysfunction. This review discusses stimulation parameters, intervention timing, and the development of innovative devices for taVNS. We further summarize the application of taVNS in improving post-stroke upper limb motor function to further promote the clinical research and application of taVNS in the rehabilitation of post-stroke upper limb motor dysfunction.


Assuntos
Acidente Vascular Cerebral , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Nervo Vago , Extremidade Superior
14.
Luminescence ; 2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38104966

RESUMO

The luminescence performance of fluorescent reagents plays a crucial role in fluorescence analysis. Therefore, in this study, a novel bi-ligand Zn-based metal-organic framework, Au nanoparticle (NP) fluorescent material was synthesized using a hydrothermal method with Zn as the metal source. Simultaneously, a DNA aptamer was introduced as a molecular recognition element to develop a Zn-based MOF@Au NPs/DNA aptamer fluorescent probe for the ultra-trace detection of thiamethoxam residues in agricultural products. The probe captured different concentrations of the target molecule, thiamethoxam, through the DNA aptamer, causing a conformational change in the DNA aptamer and bursting the fluorescence of the probe, therefore establishing a fluorometric method for thiamethoxam detection. This method is highly sensitive due to the excellent luminescence properties of the Zn-based MOF@Au NPs, and the DNA aptamer can specifically recognize thiamethoxam, offering high selectivity. The linear range of the method was 2.5-6000 × 10-11  mol L-1 , with a detection limit of 8.33 × 10-12  mol L-1 . This method was applied to the determination of actual samples, such as bananas, and the spiked recovery rate was found to be in the range 84.05-109.07%. Overall, the proposed probe has high sensitivity, high selectivity, and easy operation for the detection of thiamethoxam residues in actual samples.

15.
Mikrochim Acta ; 190(11): 435, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37837478

RESUMO

The key to developing sensors for chiral drug determination is to exclude interference from enantiomers. In this study, metal-organic frameworks (MOFs) and molecularly imprinted polymer (MIP) were introduced to prepare a chiral sensor for levofloxacin detection. The MIP was electropolymerised on the surface of the Cu/Fe-benzene-1,3,5-tricarboxylate MOF (Cu/Fe-BTC)-modified Au electrode using levofloxacin as a template molecule. After eluting the levofloxacin, a chiral sensor with recognition sites for levofloxacin was obtained. With this site as a switch, a novel method for detecting levofloxacin was established. Because of the enhanced recognition effect, the sensor can effectively exclude the enantiomeric interference of d-ofloxacin. Moreover, Cu/Fe-BTC can effectively amplify the current response signal and improve the sensitivity of the sensor. The linear range of the sensor was 5 to 4000 × 10-11 mol L-1, and the detection limit was 2.07 × 10-11 mol L-1. When applied to detecting levofloxacin in actual samples, the sensor showed a 92.7-109.8% recovery.


Assuntos
Estruturas Metalorgânicas , Impressão Molecular , Levofloxacino , Técnicas Eletroquímicas/métodos , Impressão Molecular/métodos , Polímeros Molecularmente Impressos
16.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833887

RESUMO

Epidendrum, one of the three largest genera of Orchidaceae, exhibits significant horticultural and ornamental value and serves as an important research model in conservation, ecology, and evolutionary biology. Given the ambiguous identification of germplasm and complex evolutionary relationships within the genus, the complete plastome of this genus (including five species) were firstly sequenced and assembled to explore their characterizations. The plastomes exhibited a typical quadripartite structure. The lengths of the plastomes ranged from 147,902 bp to 150,986 bp, with a GC content of 37.16% to 37.33%. Gene annotation revealed the presence of 78-82 protein-coding genes, 38 tRNAs, and 8 rRNAs. A total of 25-38 long repeats and 130-149 SSRs were detected. Analysis of relative synonymous codon usage (RSCU) indicated that leucine (Leu) was the most and cysteine (Cys) was the least. The consistent and robust phylogenetic relationships of Epidendrum and its closely related taxa were established using a total of 43 plastid genomes from the tribe Epidendreae. The genus Epidendrum was supported as a monophyletic group and as a sister to Cattleya. Meanwhile, four mutational hotspots (trnCGCA-petN, trnDGUC-trnYGUA, trnSGCU-trnGUCC, and rpl32-trnLUAG) were identified for further phylogenetic studies. Our analysis demonstrates the promising utility of plastomes in inferring the phylogenetic relationships of Epidendrum.


Assuntos
Genomas de Plastídeos , Orchidaceae , Orchidaceae/genética , Filogenia , Evolução Molecular , Sequência de Bases
17.
BMC Bioinformatics ; 23(Suppl 4): 131, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428201

RESUMO

BACKGROUND: Predicting which pathogens might exhibit antimicrobial resistance (AMR) based on genomics data is one of the promising ways to swiftly and precisely identify AMR pathogens. Currently, the most widely used genomics approach is through identifying known AMR genes from genomic information in order to predict whether a pathogen might be resistant to certain antibiotic drugs. The list of known AMR genes, however, is still far from comprehensive and may result in inaccurate AMR pathogen predictions. We thus felt the need to expand the AMR gene set and proposed a pan-genome-based feature selection method to identify potential gene sets for AMR prediction purposes. RESULTS: By building pan-genome datasets and extracting gene presence/absence patterns from four bacterial species, each with more than 2000 strains, we showed that machine learning models built from pan-genome data can be very promising for predicting AMR pathogens. The gene set selected by the eXtreme Gradient Boosting (XGBoost) feature selection approach further improved prediction outcomes, and an incremental approach selecting subsets of XGBoost-selected features brought the machine learning model performance to the next level. Investigating selected gene sets revealed that on average about 50% of genes had no known function and very few of them were known AMR genes, indicating the potential of the selected gene sets to expand resistance gene repertoires. CONCLUSIONS: We demonstrated that a pan-genome-based feature selection approach is suitable for building machine learning models for predicting AMR pathogens. The extracted gene sets may provide future clues to expand our knowledge of known AMR genes and provide novel hypotheses for inferring bacterial AMR mechanisms.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Genoma Bacteriano , Aprendizado de Máquina , Sequenciamento Completo do Genoma/métodos
18.
Plant Physiol ; 187(4): 2577-2591, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618066

RESUMO

Basic helix-loop-helix/helix-loop-helix (bHLH/HLH) transcription factors play substantial roles in plant cell elongation. In this study, two bHLH/HLH homologous proteins leaf related protein 1 and leaf-related protein 2 (AtLP1 and AtLP2) were identified in Arabidopsis thaliana. LP1 and LP2 play similar positive roles in longitudinal cell elongation. Both LP1 and LP2 overexpression plants exhibited long hypocotyls, elongated cotyledons, and particularly long leaf blades. The elongated leaves resulted from increased longitudinal cell elongation. lp1 and lp2 loss-of-function single mutants did not display distinct phenotypes, but the lp1lp2 double mutant showed decreased leaf length associated with less longitudinal polar cell elongation. Furthermore, the phenotype of lp1lp2 could be rescued by the expression of LP1 or LP2. Expression of genes related to cell elongation was upregulated in LP1 and LP2 overexpression plants but downregulated in lp1lp2 double mutant plants compared with that of wild type. LP1 and LP2 proteins could directly bind to the promoters of Longifolia1 (LNG1) and LNG2 to activate the expression of these cell elongation related genes. Both LP1 and LP2 could interact with two other bHLH/HLH proteins, IBH1 (ILI1 binding BHLH Protein1) and IBL1 (IBH1-like1), thereby suppressing the transcriptional activation of LP1 and LP2 to the target genes LNG1 and LNG2. Thus, our data suggested that LP1 and LP2 act as positive regulators to promote longitudinal cell elongation by activating the expression of LNG1 and LNG2 genes in Arabidopsis. Moreover, homodimerization of LP1 and LP2 may be essential for their function, and interaction between LP1/LP2 and other bHLH/HLH proteins may obstruct transcriptional regulation of target genes by LP1 and LP2.


Assuntos
Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Transporte/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Transporte/metabolismo , Crescimento Celular , Hipocótilo/fisiologia , Células Vegetais/fisiologia , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
19.
Trends Analyt Chem ; 157: 116738, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35874498

RESUMO

Virus threatens life health seriously. The accurate early diagnosis of the virus is vital for clinical control and treatment of virus infection. Aptamers are small single-stranded oligonucleotides (DNAs or RNAs). In this review, we summarized aptasensors for virus detection in recent years according to the classification of the viral target protein, and illustrated common detection mechanisms in the aptasensors (colorimetry, fluorescence assay, surface plasmon resonance (SPR), surface-enhanced raman spectroscopy (SERS), electrochemical detection, and field-effect transistor (FET)). Furthermore, aptamers against different target proteins of viruses were summarized. The relationships between the different biomarkers of the viruses and the detection methods, and their performances were revealed. In addition, the challenges and future directions of aptasensors were discussed. This review will provide valuable references for constructing on-site aptasensors for detecting viruses, especially the SARS-CoV-2.

20.
Mol Pharm ; 19(3): 805-818, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35148115

RESUMO

Biomimetic therapeutics offer great potential for drug delivery that avoids immune recognition. However, the coated cell membrane usually hinders the cellular uptake of nanoparticles; thus, structure-changeable formulations have attracted increasing attention. Herein, we report photolytic pyropheophorbide a (PA)-inserted red blood cell (RBC) membrane-camouflaged curcumin dimeric prodrug (CUR2-TK)-poly(lactic-co-glycolic acid) (PLGA) nanoparticles [(CUR2-TK)-PLGA@RBC-PA] for enhanced cancer therapy. In these nanoparticles, the inner core was constructed using PLGA and loaded with our synthesized reactive oxygen species (ROS)-responsive cleavable curcumin dimeric prodrug (CUR2-TK). The nanoparticles generated ROS in response to the light irradiation attributed to the incorporated PA. The ROS further triggered the lysis of the cell membrane and exposed the nanoparticles for enhanced tumor cellular uptake, and the ROS also cleaved CUR2-TK for controlled CUR drug release. Moreover, the ROS performed photodynamic therapy (PDT). The chemotherapy and PDT produced a combined effect in the treatment of cancer cells, thus enhancing anticancer therapeutic efficacy.


Assuntos
Curcumina , Nanopartículas , Neoplasias , Fotoquimioterapia , Pró-Fármacos , Linhagem Celular Tumoral , Curcumina/farmacologia , Curcumina/uso terapêutico , Membrana Eritrocítica , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
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