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1.
Bioorg Chem ; 148: 107463, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776649

RESUMO

Thrombosis leads to elevated mortality rates and substantial medical expenses worldwide. Human factor IXa (HFIXa) protease is pivotal in tissue factor (TF)-mediated thrombin generation, and represents a promising target for anticoagulant therapy. We herein isolated novel DNA aptamers that specifically bind to HFIXa through systematic evolution of ligands by exponential enrichment (SELEX) method. We identified two distinct aptamers, seq 5 and seq 11, which demonstrated high binding affinity to HFIXa (Kd = 74.07 ± 2.53 nM, and 4.93 ± 0.15 nM, respectively). Computer software was used for conformational simulation and kinetic analysis of DNA aptamers and HFIXa binding. These aptamers dose-dependently prolonged activated partial thromboplastin time (aPTT) in plasma. We further rationally optimized the aptamers by truncation and site-directed mutation, and generated the truncated forms (Seq 5-1t, Seq 11-1t) and truncated-mutated forms (Seq 5-2tm, Seq 11-2tm). They also showed good anticoagulant effects. The rationally and structurally designed antidotes (seq 5-2b and seq 11-2b) were competitively bound to the DNA aptamers and effectively reversed the anticoagulant effect. This strategy provides DNA aptamer drug-antidote pair with effective anticoagulation and rapid reversal, developing advanced therapies by safe, regulatable aptamer drug-antidote pair.


Assuntos
Antídotos , Aptâmeros de Nucleotídeos , Fator IXa , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologia , Humanos , Fator IXa/antagonistas & inibidores , Fator IXa/metabolismo , Antídotos/farmacologia , Antídotos/química , Antídotos/síntese química , Relação Dose-Resposta a Droga , Anticoagulantes/farmacologia , Anticoagulantes/química , Relação Estrutura-Atividade , Estrutura Molecular , Técnica de Seleção de Aptâmeros
3.
IEEE Trans Cybern ; 54(4): 2193-2205, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37022277

RESUMO

Unsupervised multidomain adaptation attracts increasing attention as it delivers richer information when tackling a target task from an unlabeled target domain by leveraging the knowledge attained from labeled source domains. However, it is the quality of training samples, not just the quantity, that influences transfer performance. In this article, we propose a multidomain adaptation method with sample and source distillation (SSD), which develops a two-step selective strategy to distill source samples and define the importance of source domains. To distill samples, the pseudo-labeled target domain is constructed to learn a series of category classifiers to identify transfer and inefficient source samples. To rank domains, the agreements of accepting a target sample as the insider of source domains are estimated by constructing a domain discriminator based on selected transfer source samples. Using the selected samples and ranked domains, transfer from source domains to the target domain is achieved by adapting multilevel distributions in a latent feature space. Furthermore, to explore more usable target information which is expected to enhance the performance across domains of source predictors, an enhancement mechanism is built by matching selected pseudo-labeled and unlabeled target samples. The degrees of acceptance learned by the domain discriminator are finally employed as source merging weights to predict the target task. Superiority of the proposed SSD is validated on real-world visual classification tasks.

4.
Eur J Clin Nutr ; 78(3): 228-235, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38081965

RESUMO

BACKGROUND: Accumulating evidence suggests that dietary factors may affect sleep, but the associations between dietary patterns and insomnia risk have been poorly explored. The aim of this study was to investigate if plant-based diets are associated with reduced insomnia risks in a cohort study design. METHODS: Tzu Chi Health Study participants (N = 5821) recruited from 2007 to 2009 without insomnia were followed until 2018. A traditional classification method (vegetarians vs. non-vegetarians) and a healthful plant-based index (hPDI) were used to define adherence to plant-based dietary patterns. Incident cases of insomnia were ascertained by linking with the National Health Insurance Research Database (NHIRD). Associations between plant-based diets and insomnia were estimated using Cox proportional hazard models. RESULTS: A total of 464 incident cases of insomnia were identified in the 55,562 person-years of follow up. Insomnia risk was lower in vegetarians when compared to non-vegetarians, hazard ratios (HR) 0.47 (95% CI: 0.27, 0.81) and 0.71 (95% CI: 0.55, 0.91) for males and females respectively. Male participants with the highest hPDI were associated with a significant lower risk of insomnia (HR 0.50 [95% CI: 0.30, 0.85]) when compared to those in the lowest quintile. No association between adherence to hPDI and insomnia in female participants was observed. CONCLUSIONS: Our study showed that vegetarians are associated with a lower risk of insomnia, but there may be sex-specific associations between adherence to hPDI and insomnia risk. These favorable associations are important when considering plant-based diets for their potential additional sleep benefits.


Assuntos
Dieta Vegetariana , Distúrbios do Início e da Manutenção do Sono , Masculino , Feminino , Humanos , Estudos Prospectivos , Estudos de Coortes , Padrões Dietéticos , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Dieta
5.
Molecules ; 28(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38067658

RESUMO

Ferroptosis is a form of regulated cell death that is characterized by the accumulation of iron-dependent lipid peroxides. The regulation of ferroptosis involves both non-enzymatic reactions and enzymatic mechanisms. Natural products have demonstrated potential effects on various enzymes, including GPX4, HO-1, NQO1, NOX4, GCLC, and GCLM, which are mainly involved in glutathione metabolic pathway or oxidative stress regulation, and ACSL3 and ACSL4, which mainly participate in lipid metabolism, thereby influencing the regulation of ferroptosis. In this review, we have provided a comprehensive overview of the existing literature pertaining to the effects of natural products on enzymes involved in ferroptosis and discussed their potential implications for the prevention and treatment of ferroptosis-related diseases. We also highlight the potential challenge that the majority of research has concentrated on investigating the impact of natural products on the expression of enzymes involving ferroptosis while limited attention is given to the regulation of enzyme activity. This observation underscores the considerable potential and scope for exploring the influence of natural products on enzyme activity.


Assuntos
Produtos Biológicos , Ferroptose , Produtos Biológicos/farmacologia , Glutationa , Ferro , Metabolismo dos Lipídeos
6.
J Genet ; 1022023.
Artigo em Inglês | MEDLINE | ID: mdl-37798872

RESUMO

This study aimed to identify the potential circular RNAs (circRNAs) in exosomes isolated from serum as biomarkers of lower limb vascular disease (LLVD) in patients with type 2 diabetes mellitus (T2DM). This research collected circRNAs from exosomes isolated from three T2DM patients and three T2DM patients with LLVD for microarray analysis. Five candidate biomarkers derived from differentially expressed circRNAs were then validated by quantitative real-time polymerase chain reaction in 20 T2DM patients and 20 T2DM patients with LLVD. Finally, expression levels of circRNAs were validated in 160 samples. Significant differences in the expression of 295 circRNAs were found between T2DM controls and T2DM patients with LLVD. Among them, 191 differentially expressed circRNAs were upregulated, and 104 were downregulated in T2DM patients with LLVD. Three upregulated and two downregulated circRNAs were further confirmed in 40 samples. According to the testing of 160 samples, hsa_circ_0001842 showed a noticeable specificity in the T2DM patients with LLVD group (n = 80), with an area under the curve (AUC) of 0.79, a sensitivity of 88.75%, and a specificity of 68.75%. In conclusion, hsa_circ_0001842 was found as a potential diagnostic biomarker for T2DM with LLVD.


Assuntos
Diabetes Mellitus Tipo 2 , RNA Circular , Humanos , RNA Circular/genética , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Biomarcadores/metabolismo , Análise em Microsséries , Reação em Cadeia da Polimerase em Tempo Real
7.
Front Microbiol ; 14: 1249813, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795295

RESUMO

Oilseed rape (Brassica napus L.) is highly susceptible to infection from the soilborne pathogen Plasmodiophora brassicae Woronin that causes clubroot disease and deleteriously affects production throughout the world. In this study, biological control resources were explored by isolating 237 strains of bacteria from fields of oilseed rape using the gradient dilution coating method. A strain with strong antagonistic ability was screened using a plate confrontation test and designated X216. It was identified as Streptomyces melanosporofaciens owing to its morphological characteristics and 16S rRNA gene sequence. This study also examined the lethality of strain X216 to the resting spores of P. brassicae, its influence on infection in root hairs, and its ability to control clubroot on oilseed rape. The corrected lethality rate on resting spores after strain X216 had been used for 14 days was 56.59% ± 1.97%, which was significantly higher than the use of 75% of the fungicides chlorothalonil WP and 20% Fluazinam SC. Significantly fewer root hairs were infected after this treatment. A pot test showed that X216 was 62.14% effective at controlling the disease, which was not significantly different from that of the fungicide 100 g L-1 cyazofamid SC diluted 1,000-fold but significantly higher than those of 75% chlorothalonil and 50% carbendazim WP. Strain X216 controlled 43.16% of the incidence of clubroot in the field, which could significantly reduce the disease index of oilseed rape clubroot. Therefore, strain X216 is promising to study for the biological control of oilseed rape clubroot.

8.
Heliyon ; 9(9): e19587, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37810008

RESUMO

Objective: To elaborate the clinical characteristics of congenital pulmonary lymphangiectasia in a neonate with hydrops fetalis. This could be an alert in considering it as a differential diagnosis for neonates with acute respiratory failure. Methods: We reviewed and analyzed single-center registry patients who underwent cadaveric autopsies in the Department of Pathology at Children's Hospital from January 1, 2010 to December 31, 2021. We aimed to explore the perinatal clinical manifestations associated with congenital pulmonary lymphangiectasis (CPL). Literature was reviewed to summarize the common features of CPL in pregnancy from individual cases, and to facilitate prenatal and intrapartum diagnosis prognosis, and assessment of medical emergencies. Results: Thirty-four patients were included, and the main causes of death were intrauterine infection (n = 6), severe pneumonia (n = 11), spontaneous pneumothorax (n = 3), hemorrhagic shock (n = 2), CPL (n = 1), and other non-respiratory failure manifestations (n = 12). The manifestations of respiratory distress in CPL were different from those of intrauterine infections and respiratory failure due to parenchymal lung lesions. These include prenatal presentation of fetal edema, postnatal presentation of uncorrectable respiratory failure with severe hypoproteinemia, pneumothorax and interstitial emphysema on imaging, and poor response to treatment with surfactant-like substances. Thus, when the pregnancy tests reveal fetal edema and postnatal presentation of acute, respiratory distress, the diagnosis of CPL should be considered first, and corresponding medical care should be implemented to improve the survival rate. Conclusions: CPL is a rare pulmonary defect, and its perinatal clinical manifestations can often be neglected. For children with prenatal fetal edema who die after birth due to progressive respiratory distress, a timely autopsy is of utmost importance to clarify the etiology, improve understanding of CPL, and diagnose early to allow for proper prenatal and postnatal care.

9.
J Am Chem Soc ; 145(36): 19503-19507, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37638713

RESUMO

Tile-based DNA self-assembly provides a versatile approach for the construction of a wide range of nanostructures for various applications such as nanomedicine and advanced materials. The inter-tile interactions are primarily programmed by base pairing, particularly Watson-Crick base pairing. To further expand the tool box for DNA nanotechnology, herein, we have designed DNA tiles that contain both ligands and aptamers. Upon ligand-aptamer binding, tiles associate into geometrically well-defined nanostructures. This strategy has been demonstrated by the assembly of a series of DNA nanostructures, which have been thoroughly characterized by gel electrophoresis and atomic force microscopy. This new inter-tile cohesion could bring new potentials to DNA self-assembly in the future. For example, the addition of free ligand could modulate the nanostructure formation. In the case of biological ligands, DNA self-assembly could be related to the presence of certain ligands.


Assuntos
DNA , Oligonucleotídeos , Ligantes , Pareamento de Bases , Microscopia de Força Atômica
10.
BMC Musculoskelet Disord ; 24(1): 627, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532978

RESUMO

OBJECTIVE: To investigate the characteristics and seasonal patterns of distal radius fractures (DRFs) over the preceding five years, with the aim of establishing a clinical foundation for the prevention and management of such fractures within this region. METHODS: Utilizing the Picture Archiving and Communication Systems (PACS), the clinical records of 1954 patients diagnosed with DRFs and admitted to the Affiliated Hospital of Jiangsu University between January 2017 and December 2021 were compiled. The analysis encompassed factors such as age, gender, visitation timing, fracture side, and presence of osteoporosis. RESULTS: Out of the total 1954 distal radius fractures, 731 were males (37.4%) and the male to female ratio was 0.59:1. The median age of patients with DRFs was 56 years, with the 25th percentile being 38 years and the 75th percentile being 67 years. The average age was 50 years (standard deviation 23.3) and 1033 cases (52.7%) occurred on the left side, 885 cases (45.1%) on the right side, and 36 cases (1.8%) were bilateral, with the left side being the most frequently affected. The age group of 61-70 years (23.9%, 467/1954) exhibited the highest proportion, and the most prominent age group for males was 11-20 years (23.8%, 174/731), whereas for females it was 61-70 years (30.83%, 377/1223). In the 50 years and older group, there were 276 males and 991 females (ratio 1:3.59), with osteoporosis in 536 cases, accounting for 42.03% of the group. In terms of seasonal distribution, the highest incidence occurred during the summer and autumn months (55.1%, 1076/1954) and there were gender differences in different seasons. CONCLUSION: In east China, DRFs were predominantly female and left-sided, with the highest proportion in the age group of 61-70 years and in summer and autumn. Furthermore, gender differences were observed between the warm and cold seasons.


Assuntos
Osteoporose , Fraturas do Rádio , Fraturas do Punho , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Criança , Adolescente , Adulto Jovem , Adulto , Fraturas do Rádio/epidemiologia , Fraturas do Rádio/terapia , Fraturas do Rádio/etiologia , Osteoporose/epidemiologia , Osteoporose/complicações , Estudos de Coortes , China/epidemiologia
11.
Front Oncol ; 13: 1194232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529690

RESUMO

Background: Lynch syndrome (LS)-associated glioblastoma (GBM) is rare in clinical practice, and simultaneous occurrence with cutaneous porokeratosis is even rarer. In this study, we analyzed the clinicopathological and genetic characteristics of LS-associated GBMs and concurrent porokeratosis, as well as evaluated the tumor immune microenvironment (TIME) of LS-associated GBMs. Methods: Immunohistochemical staining was used to confirm the histopathological diagnosis, assess MMR and PD-1/PD-L1 status, and identify immune cell subsets. FISH was used to detect amplification of EGFR and PDGFRA, and deletion of 1p/19q and CDKN2A. Targeted NGS assay analyzed somatic variants, MSI, and TMB status, while whole-exome sequencing and Sanger sequencing were carried out to analyze the germline mutations. Results: In the LS family, three members (I:1, II:1 and II:4) were affected by GBM. GBMs with loss of MSH2 and MSH6 expression displayed giant and multinucleated bizarre cells, along with mutations in ARID1A, TP53, ATM, and NF1 genes. All GBMs had TMB-H but not MSI-H. CD8+ T cells and CD163+ macrophages were abundant in each GBM tissue. The primary and recurrent GBMs of II:1 showed mesenchymal characteristics with high PD-L1 expression. The family members harbored a novel heterozygous germline mutation in MSH2 and FDPS genes, confirming the diagnosis of LS and disseminated superficial actinic porokeratosis. Conclusion: LS-associated GBM exhibits heterogeneity in clinicopathologic and molecular genetic features, as well as a suppressive TIME. The presence of MMR deficiency and TMB-H may serve as predictive factors for the response to immune checkpoint inhibitor therapy in GBMs. The identification of LS-associated GBM can provide significant benefits to both patients and their family members, including accurate diagnosis, genetic counseling, and appropriate screening or surveillance protocols. Our study serves as a reminder to clinicians and pathologists to consider the possibility of concurrent genetic syndromes in individuals or families.

12.
Anal Chem ; 95(26): 9754-9760, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37343019

RESUMO

De novo design of functional biomacromolecules is of great interest to a wide range of fundamental science and technological applications, including understanding life evolution and biomacromolecular structures, developing novel catalysts, inventing medicines, and exploring high-performance materials. However, it is an extremely challenging task and its success is very limited. It requires a deep understanding of the relationships among the primary sequences, the 3D structures, and the functions of biomacromolecules. Herein, we report a rational, de novo design of a DNA aptamer that can bind melamine with high specificity and high affinity (dissociation constant Kd = 4.4 nM). The aptamer is essentially a DNA triplex, but contains an abasic site, to which the melamine binds. The aptamer-ligand recognition involves hydrogen-bonding, π-π stacking, and electrostatic interactions. This strategy has been further tested by designing aptamers to bind to guanosine. It is conceivable that such a rational strategy, with further development, would provide a general framework for designing functional DNA molecules.


Assuntos
Aptâmeros de Nucleotídeos , DNA , DNA/química , Aptâmeros de Nucleotídeos/química , Ligação de Hidrogênio
13.
Chin Med ; 18(1): 74, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37337262

RESUMO

BACKGROUND: Herbal medicine Sanqi (SQ), the dried root or stem of Panax notoginseng (PNS), has been reported to have anti-diabetic and anti-obesity effects and is usually administered as a decoction for Chinese medicine. Alternative to utilizing PNS pure compound for treatment, we are motivated to propose an unconventional scheme to investigate the functions of PNS mixture. However, studies providing a detailed overview of the transcriptomics-based signaling network in response to PNS are seldom available. METHODS: To explore the reasoning of PNS in treating metabolic disorders such as insulin resistance, we implemented a systems biology-based approach with RNA sequencing (RNA-seq) and miRNA sequencing data to elucidate key pathways, genes and miRNAs involved. RESULTS: Functional enrichment analysis revealed PNS up-regulating oxidative stress-related pathways and down-regulating insulin and fatty acid metabolism. Superoxide dismutase 1 (SOD1), peroxiredoxin 1 (PRDX1), heme oxygenase-1 (Hmox1) and glutamate cysteine ligase (GCLc) mRNA and protein levels, as well as related miRNA levels, were measured in PNS treated rat pancreatic ß cells (INS-1). PNS treatment up-regulated Hmox1, SOD1 and GCLc expression while down-regulating miR-24-3p and miR-139-5p to suppress oxidative stress. Furthermore, we verified the novel interactions between miR-139-5p and miR-24-3p with GCLc and SOD1. CONCLUSION: This work has demonstrated the mechanism of how PNS regulates cellular molecules in metabolic disorders. Therefore, combining omics data with a systems biology strategy could be a practical means to explore the potential function and molecular mechanisms of Chinese herbal medicine in the treatment of metabolic disorders.

14.
Ann Transl Med ; 11(6): 243, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37082658

RESUMO

Background: According to preclinical experiments, Pseudomonas aeruginosa mannose-sensitive hemagglutinin (PA-MSHA) exerts antiproliferative effects against breast cancer cells. It has been approved by the State Food and Drug Administration in China for complementary cancer treatment, and its safety has been confirmed in previous clinical trials. The present randomized, controlled, double-blind clinical trial was conducted to investigate the efficacy and safety of neoadjuvant PA-MSHA and placebo with chemotherapy in patients with human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Methods: Eligible patients aged 18 years or older with previously untreated HER2-negative stage II-III breast cancer were enrolled and randomly assigned at a 1:1 ratio to receive neoadjuvant chemotherapy with PA-MSHA or a placebo. The Response Evaluation Criteria in Solid Tumors (RECIST) was used to assess clinical response every 2 cycles. The primary endpoint was the objective response rate (ORR) based on the clinical response following neoadjuvant chemotherapy. Results: A total of 75 patients were randomly assigned to either the PA-MSHA group (37 patients) or the control group (38 patients). The ORR was found to be significantly higher in the PA-MSHA group compared with the control group [86.5% versus 60.5%; rate difference 26.0; 95% confidence interval (CI): 5.9-43.5%; P=0.011]. The pathological complete response (pCR) and survival outcomes did not differ significantly between the 2 groups. Patients with immune-related adverse events (irAEs) appeared to benefit from the PA-MSHA treatment, with greater disease-free, relapse-free, and overall survival. The application of PA-MSHA to neoadjuvant chemotherapy did not increase the incidence of severe adverse events. Moreover, the addition of PA-MSHA increased serum interferon-γ levels and the percentage of peripheral blood T cells, CD8+/CD4+ T cells, CD8+CD28+ T cells, and natural killer (NK) cells, and decreased serum interleukin 4 levels. Conclusions: The addition of PA-MSHA to neoadjuvant chemotherapy is an effective alternative regimen for HER2-negative breast cancer. Patients with irAEs caused by PA-MSHA may obtain more benefits from this treatment. Trial Registration: Chinese Clinical Trial Registry ChiCTR-TRC-10000794.

15.
Acta Biomater ; 164: 387-396, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37088158

RESUMO

Short peptides are poor immunogens. One way to increase their immune responses is by arraying immunogens in multivalency. Simple and efficient scaffolds for spatial controlling the inter-antigen distance and enhancing immune activation are required. Here, we report a molecular vaccine design principle that maximally drives potent SARS-CoV-2 RBD subunit vaccine on DNA duplex to induce robust and efficacious immune responses in vivo. We expect that the DNA-peptide epitope platform represents a facile and generalizable strategy to enhance the immune response. STATEMENT OF SIGNIFICANCE: DNA scaffolds offer a biocompatible and convenient platform for arraying immunogens in multivalency antigenic peptides, and spatially control the inter-antigen distance. This can effectively enhance immune response. Peptide (instead of entire protein) vaccines are highly attractive. However, short peptides are poor immunogens. Our DNA scaffolded multivalent peptide immunogen system induced robust and efficacious immune response in vivo as demonstrated by the antigenic peptide against SARS-CoV-2. The present strategy could be readily generalized and adapted to prepare multivalent vaccines against other viruses or disease. Particularly, the different antigens could be integrated into one single vaccine and lead to super-vaccines that can protect the host from multiple different viruses or multiple variants of the same virus.


Assuntos
COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19/farmacologia , SARS-CoV-2 , Vacinas Combinadas , COVID-19/prevenção & controle , Peptídeos , DNA
16.
Sci Total Environ ; 875: 162592, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889408

RESUMO

This study quantitatively investigated the effect of dissolved oxygen (DO) concentration on aerobic denitrification, and showed the mechanism of aerobic denitrification from the perspective of electron competition by cultivating Pseudomonas stutzeri T13, a typical aerobic denitrifier, in an oxygen-based membrane biofilm reactor (O2-based MBfR). The experiments showed that when the O2 pressure increased from 2 to 10 psig , the average effluent DO concentration during steady-state phases increased from 0.02 to 4.23 mg/L, and the corresponding mean NO3--N removal efficiency slightly decreased from 97.2 % to 90.9 %. Compared to the maximum theoretical flux of O2 in various phases, the actual O2 transfer flux increased from a limited status (2.07 e- eq m-2 d-1 at 2 psig) to an excessive status (5.58 e- eq m-2 d-1 at 10 psig). The increase of DO inhibited the electron availability for aerobic denitrification, which decreased from 23.97 % to 11.46 %, accompanying the increased electron availability for aerobic respiration from 15.87 % to 28.36 %. Unlike the napA and norB genes, the expression of the nirS and nosZ genes was significantly affected by DO, with the highest relative fold-changes of 6.5 and 6.13 at 4 psig O2, respectively. The results contribute to clarifying the mechanism of aerobic denitrification from the quantitative perspective of electron distribution and the qualitative perspective of gene expression, which benefits the control and practical application of aerobic denitrification for wastewater treatment.


Assuntos
Desnitrificação , Nitratos , Oxigênio , Elétrons , Biofilmes , Reatores Biológicos , Nitrogênio
17.
Analyst ; 148(8): 1858-1866, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36942467

RESUMO

Adenosine levels are important in various physiological and pathological activities, but detecting them is difficult because of interference from a complex matrix. This study designed a series of DNA oligomers rich in thymine to enrich adenosine. Their binding affinity (Kd range: 1.25-5.0 mM) to adenosine varied based on the DNA secondary structures, with a clamped hairpin structure showing the highest binding affinity. Compared to other designs, this clamped DNA hairpin underwent the least conformational change during adenosine binding. These DNAs also suppressed the precipitation of supersaturated adenine. Taken together, these results suggest that thymine-rich DNAs could be used to enrich and separate adenosine.


Assuntos
Adenosina , Timina , Timina/química , Conformação de Ácido Nucleico , DNA/química , Adenina/química
18.
Food Chem ; 414: 135712, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36808023

RESUMO

Previous research indicated lotus leaves extract could effectively inhibit advanced glycation end-products (AGEs) formation, but the optimal extraction condition, bio-active compounds and interaction mechanism remain unclear. The current study was designed to optimize the extraction parameters of AGEs inhibitors from lotus leaves by bio-activity-guided approach. The bio-active compounds were enriched and identified, the interaction mechanisms of inhibitors with ovalbumin (OVA) were investigated by fluorescence spectroscopy and molecular docking. The optimum extraction parameters were solid-liquid ratio of 1:30, ethanol concentration of 70 %, ultrasonic time of 40 min, temperature of 50 °C, and power of 400 W. Isoquercitrin, hyperoside, astragalin, and trifolin were identified from the 80 % ethanol fraction of lotus leaves (80HY). Hyperoside and isoquercitrin were dominant AGEs inhibitors and accounted for 55.97 % of 80HY. Isoquercitrin, hyperoside, trifolin interacted with OVA via the same mechanism, hyperoside exhibited the strongest affinity, trifolin caused the most conformational changes.


Assuntos
Reação de Maillard , Extratos Vegetais , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Ovalbumina/análise , Produtos Finais de Glicação Avançada/análise , Folhas de Planta/química
19.
Macromol Biosci ; 23(3): e2200453, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36542841

RESUMO

Antisense DNA oligonucleotide (AS) technology is a promising approach to regulate gene expression and cellular processes. For example, ASs can be used to capture the overexpressed, oncogenic miRNAs in tumors to suppress tumor growth. Among many challenges faced by AS approach is the degradation of ASs by nucleases under physiological conditions. Elongating the AS lifespan can substantially enhance the functions of AS. The paper reports a simple strategy to increase the stability of ASs. The authors discover that the ASs degrade quickly if their ends are in unpaired, single-stranded form, but much slower if their ends are in paired duplex form. It is conceivable to integrate this strategy with other strategies (such as chemical modification of ASs backbones) to maximally increase the ASs stabilities.


Assuntos
Neoplasias , Oligonucleotídeos Antissenso , DNA/genética , DNA Antissenso , Neoplasias/genética , Neoplasias/terapia , Oligonucleotídeos , Oligonucleotídeos Antissenso/genética
20.
Food Chem ; 400: 133961, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36084584

RESUMO

The broad application prospect of fish gelatin makes the traceability and identification of fish gelatin imminent. High performance liquid chromatography and high-resolution mass spectrometry (HPLC-MS/MS) was used to identify fish gelatins in seven commercial cyprinid fishes, namely, black carp, grass carp, silver carp, bighead carp, common carp, crucian carp, and Wuchang bream. By comparison with theoretical mammalian collagen (bovine and porcine collagen), the common and unique theoretical peptides were found in the collagen of grass carp, silver carp, and crucian carp, respectively. HPLC-MS/MS results showed that 7 common characteristic peptides were obtained from seven cyprinid fish gelatins. Moreover, 44, 36, and 42 unique characteristic peptides were detected in the gelatins of grass carp, silver carp, and crucian carp, respectively. The combined use of common and unique characteristic peptides could improve the accuracy and authenticity of traceability and identification of fish gelatin in comparison with mammalian gelatin.


Assuntos
Carpas , Gelatina , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Colágeno , Peixes , Gelatina/química , Mamíferos , Suínos , Espectrometria de Massas em Tandem
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