Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 234
Filtrar
1.
Int J Biol Macromol ; 269(Pt 2): 132025, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704076

RESUMO

The intestine defends against pathogenic microbial invasion via the secretion of host defense peptides (HDPs). Nutritional immunomodulation can stimulate the expression of endogenous HDPs and enhance the body's immune defense, representing a novel non-antibiotic strategy for disease prevention. The project aims to explore the regulatory mechanism of protegrin-1 (PG-1) expression using sodium phenylbutyrate (PBA) by omics sequencing technology and further investigate the role of key regulatory genes on intestinal health. The results showed that PBA promoted PG-1 expression in intestinal epithelial cells based on cell density through epidermal growth factor receptor (EGFR) and G protein-coupled receptor (GPR43). Transcriptome sequencing and microRNA sequencing revealed that C-X-C motif chemokine receptor 2 (CXCR2) exhibited interactions with PG-1. Pre-treatment cells with a CXCR2 inhibitor (SB225002) effectively suppressed the induction of PG-1 by PBA. Furthermore, SB225002 significantly suppressed the gene expression of HDPs in the jejunum of mice without influencing on the morphology, number of goblet cells, and proliferation of the intestine. CXCR2 inhibition significantly reduced the expression of HDPs during E. coli infection, and resulted in the edema of jejunal epithelial cells. The 16S rDNA analysis of cecal contents showed that the E. coli and SB225002 treatments changed gut microbiota diversity and composition at different taxonomic levels. Correlation analysis suggested a potential regulatory relationship between gut microbiota and HDPs. To that end, a gene involved in the HDP expression, CXCR2, has been identified in the study, which contributes to improving intestinal immune function. PBA may be used as a functional additive to regulate intestinal mucosal function, thereby enhancing the health of the intestinal and host.


Assuntos
Homeostase , Mucosa Intestinal , Receptores de Interleucina-8B , Animais , Humanos , Masculino , Camundongos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/genética , Infecções por Escherichia coli/genética , Microbioma Gastrointestinal/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Receptores Acoplados a Proteínas G , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo
2.
ACS Sens ; 9(6): 3377-3386, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38783424

RESUMO

Comprehending the charge transfer mechanism at the semiconductor interfaces is crucial for enhancing the electronic and optical performance of sensing devices. Yet, relying solely on single signal acquisition methods at the interface hinders a comprehensive understanding of the charge transfer under optical excitation. Herein, we present an integrated photoelectrochemical surface-enhanced Raman spectroscopy (PEC-SERS) platform based on quantum dots/metal-organic framework (CdTe/Yb-TCPP) nanocomposites for investigating the charge transfer mechanism under photoexcitation in multiple dimensions. This integrated platform allows simultaneous PEC and SERS measurements with a 532 nm laser. The obtained photocurrent and Raman spectra of the CdTe/Yb-TCPP nanocomposites are simultaneously influenced by variable bias voltages, and the correlation between them enables us to predict the charge transfer pathway. Moreover, we integrate gold nanorods (Au NRs) into the PEC-SERS system by using magnetic separation and DNA biometrics to construct a biosensor for patulin detection. This biosensor demonstrates the voltage-driven ON/OFF switching of PEC and SERS signals, a phenomenon attributed to the plasmon resonance effect of Au NRs at different voltages, thereby influencing charge transfer. The detection of patulin in apples verified the applicability of the biosensor. The study offers an efficient approach to understanding semiconductor-metal interfaces and presents a new avenue for designing high-performance biosensors.


Assuntos
Compostos de Cádmio , Técnicas Eletroquímicas , Ouro , Patulina , Pontos Quânticos , Semicondutores , Análise Espectral Raman , Telúrio , Análise Espectral Raman/métodos , Telúrio/química , Compostos de Cádmio/química , Técnicas Eletroquímicas/métodos , Pontos Quânticos/química , Patulina/análise , Ouro/química , Estruturas Metalorgânicas/química , Técnicas Biossensoriais/métodos , Nanotubos/química , Itérbio/química , Malus/química , Nanocompostos/química
3.
J Anim Sci Biotechnol ; 15(1): 79, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38760843

RESUMO

BACKGROUND: Infection with pathogenic bacteria during nonantibiotic breeding is one of the main causes of animal intestinal diseases. Oleanolic acid (OA) is a pentacyclic triterpene that is ubiquitous in plants. Our previous work demonstrated the protective effect of OA on intestinal health, but the underlying molecular mechanisms remain unclear. This study investigated whether dietary supplementation with OA can prevent diarrhea and intestinal immune dysregulation caused by enterotoxigenic Escherichia coli (ETEC) in piglets. The key molecular role of bile acid receptor signaling in this process has also been explored. RESULTS: Our results demonstrated that OA supplementation alleviated the disturbance of bile acid metabolism in ETEC-infected piglets (P < 0.05). OA supplementation stabilized the composition of the bile acid pool in piglets by regulating the enterohepatic circulation of bile acids and significantly increased the contents of UDCA and CDCA in the ileum and cecum (P < 0.05). This may also explain why OA can maintain the stability of the intestinal microbiota structure in ETEC-challenged piglets. In addition, as a natural ligand of bile acid receptors, OA can reduce the severity of intestinal inflammation and enhance the strength of intestinal epithelial cell antimicrobial programs through the bile acid receptors TGR5 and FXR (P < 0.05). Specifically, OA inhibited NF-κB-mediated intestinal inflammation by directly activating TGR5 and its downstream cAMP-PKA-CREB signaling pathway (P < 0.05). Furthermore, OA enhanced CDCA-mediated MEK-ERK signaling in intestinal epithelial cells by upregulating the expression of FXR (P < 0.05), thereby upregulating the expression of endogenous defense molecules in intestinal epithelial cells. CONCLUSIONS: In conclusion, our findings suggest that OA-mediated regulation of bile acid metabolism plays an important role in the innate immune response, which provides a new diet-based intervention for intestinal diseases caused by pathogenic bacterial infections in piglets.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38649786

RESUMO

Bile acids are synthesised in the liver and are essential amphiphilic steroids for maintaining the balance of cholesterol and energy metabolism in livestock and poultry. They can be used as novel feed additives to promote fat utilisation in the diet and the absorption of fat-soluble substances in the feed to improve livestock performance and enhance carcass quality. With the development of understanding of intestinal health, the balance of bile acid metabolism is closely related to the composition and growth of livestock intestinal microbiota, inflammatory response, and metabolic diseases. This paper systematically reviews the effects of bile acid metabolism on gut health and gut microbiology in livestock. In addition, our paper summarised the role of bile acid metabolism in performance and disease control.

5.
Clin Lab ; 70(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623663

RESUMO

BACKGROUND: This study aimed to assess the performance of the newborn screening laboratories in China through retrospective analysis of the coefficient of variation (CV) of the internal quality control (IQC) data in the national tandem mass spectrometry screening for inherited metabolic disorders in newborns. METHODS: From 2015 to 2021, the IQC data of amino acid and acylcarnitine test were collected twice each year. CVmonthly in-control was calculated by excluding outliers for the current month and its discrete distribution and changes in trend were comprehensively evaluated for both normal and high concentration levels. The proportion of laboratories meeting both 1/3 and 1/4 quality criteria of the total error allowable (TEa), based on the CVmonthly in-control for each testing item, was calculated. RESULTS: The analysis of CVmonthly in-control for the two concentration levels for the amino acids and acylcarnitine parameters showed that CVmonthly in-control for the normal concentration levels were more discrete before 2018, while CVmonthly in-control for the high concentration levels were less discrete than the normal concentration levels, but there were relatively more outliers. More than 80% of laboratories were able to meet the 1/3 TEa standard for each test at the high concentration level, while the pass rate for the 1/4 TEa standard was significantly lower than 80% (except for C2). CONCLUSIONS: According to the current status of testing in China, it is recommended to use 1/3TEa as the imprecision level standard; for laboratories with relatively high precision, the 1/4TEa standard can be used.


Assuntos
Carnitina/análogos & derivados , Triagem Neonatal , Espectrometria de Massas em Tandem , Recém-Nascido , Humanos , Estudos Retrospectivos , Controle de Qualidade , China
6.
Food Chem ; 448: 139128, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574714

RESUMO

Food contamination from microbial deterioration requires the development of potent antimicrobial peptides (AMPs). The deployment of approved AMPs as dietary preservatives is limited due to barriers such as instability, toxicity, and high synthetic costs. This exploration utilizes the primary structural elements of the Trp-pocket backbone to engineer a series of ß-hairpin AMPs (XWRWRPGXKXXR-NH2, X representing I, V, F, and/or L). Peptides WpLF, with Phe as X and Leu arranged at the 11th position, demonstrated exceptional selectivity index (SI = 123.08) and sterilization effects both in vitro and in vivo. WpLF consistently exhibited stable bacteriostasis, regardless of physiological salts, serum, and extreme pH. Mechanistic analysis indicated that the peptide penetrates microbial cell membranes, inducing membrane disruption, thereby impeding drug resistance evolution. Conclusively, AMPs engineered by the Trp-pocket skeleton hold substantial potential as innovative biological preservatives in food preservation, providing valuable insights for sustainable and safe peptide-based food preservatives.

7.
J Psychosom Res ; 179: 111620, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430795

RESUMO

OBJECTIVE: Numerous studies have reported the close association of depression with obstructive sleep apnea (OSA). However, the causal nature and direction remain unclear. This study aimed to identify the genetic causal relationship between depression and OSA using Mendelian randomization (MR). METHODS: Based on publicly available genome-wide association studies data of depression and OSA, we conducted a bidirectional two-sample MR study. The inverse-variance weighted (IVW) was used as the main analysis method. Moreover, multivariable MR was performed to further explore the underlying genetic causality of OSA and depression after adjusting for several potential mediators. RESULTS: The univariable MR analysis revealed a significant causality of depression on the susceptibility of OSA (ORivw = 1.29, 95%CI:1.11,1.50; p < 0.001). This relationship was evidenced by the phenotypes for broad depression (ORivw = 3.30, 95%CI: 1.73, 6.29; p < 0.001), probable major depression (ORivw = 18.79, 95%CI: 5.69, 61.99; p < 0.001), and ICD-10 major depression (ORivw = 23.67, 95%CI: 4.13, 135.74; p < 0.001). In the reverse direction, no significant causal effect of OSA on depression was found. After adjusting for smoking, alcohol use, obesity, type 2 diabetes, insomnia, age, gender, and codeine, most of these results suggested that depression remained significantly and positively associated with OSA. CONCLUSION: These findings may contribute to the understanding of the etiology of depression and OSA and also suggest the clinical significance of controlling depression for the prevention of OSA.


Assuntos
Transtorno Depressivo Maior , Diabetes Mellitus Tipo 2 , Apneia Obstrutiva do Sono , Humanos , Depressão/epidemiologia , Depressão/genética , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/genética , Masculino , Feminino
8.
Cell Death Dis ; 15(3): 216, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485947

RESUMO

Despite progressive improvements in the survival rate of pediatric B-cell lineage acute lymphoblastic leukemia (B-ALL), chemoresistance-induced disease progression and recurrence still occur with poor prognosis, thus highlighting the urgent need to eradicate drug resistance in B-ALL. The 6-mercaptopurine (6-MP) is the backbone of ALL combination chemotherapy, and resistance to it is crucially related to relapse. The present study couples chemoresistance in pediatric B-ALL with histidine metabolism deficiency. Evidence was provided that histidine supplementation significantly shifts the 6-MP dose-response in 6-MP-resistant B-ALL. It is revealed that increased tetrahydrofolate consumption via histidine catabolism partially explains the re-sensitization ability of histidine. More importantly, this work provides fresh insights into that desuccinylation mediated by SIRT5 is an indispensable and synergistic requirement for histidine combination therapy against 6-MP resistance, which is undisclosed previously and demonstrates a rational strategy to ameliorate chemoresistance and protect pediatric patients with B-ALL from disease progression or relapse.


Assuntos
Linfoma de Burkitt , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Sirtuínas , Humanos , Criança , Mercaptopurina/farmacologia , Mercaptopurina/uso terapêutico , Histidina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Linfoma de Burkitt/tratamento farmacológico , Recidiva , Progressão da Doença
9.
Sleep Breath ; 28(3): 1051-1065, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38308748

RESUMO

Obstructive sleep apnea (OSA) is a common respiratory disorder. Multiple organs, especially the central nervous system (CNS), are damaged, and dysfunctional when intermittent hypoxia (IH) occurs during sleep for a long time. The quality of life of individuals with OSA is significantly impacted by cognitive decline, which also escalates the financial strain on their families. Consequently, the development of novel therapies becomes imperative. IH induces oxidative stress, endoplasmic reticulum stress, iron deposition, and neuroinflammation in neurons. Synaptic dysfunction, reactive gliosis, apoptosis, neuroinflammation, and inhibition of neurogenesis can lead to learning and long-term memory impairment. In addition to nerve injury, the role of IH in neuroprotection was also explored. While causing neuron damage, IH activates the neuronal self-repairing mechanism by regulating antioxidant capacity and preventing toxic protein deposition. By stimulating the proliferation and differentiation of neural stem cells (NSCs), IH has the potential to enhance the ratio of neonatal neurons and counteract the decline in neuron numbers. This review emphasizes the perspectives and opportunities for the neuroprotective effects of IH and informs novel insights and therapeutic strategies in OSA.


Assuntos
Hipóxia , Neurônios , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Neurônios/fisiologia , Hipóxia/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/etiologia , Cognição/fisiologia , Estresse Oxidativo/fisiologia , Animais
10.
J Med Chem ; 67(5): 4131-4149, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38420875

RESUMO

In the pursuit of combating multidrug-resistant bacteria, antimicrobial peptides (AMPs) have emerged as promising agents; however, their application in clinical settings still presents challenges. Specifically, the exploration of crucial structural parameters that influence the antibacterial spectrum of AMPs and the subsequent development of tailored variants with either broad- or narrow-spectrum characteristics to address diverse clinical therapeutic needs has been overlooked. This study focused on investigating the effects of amino acid sites and hydrophobicity on the peptide's antibacterial spectrum through Ala scanning and fixed-point hydrophobic amino acid substitution techniques. The findings revealed that specific amino acid sites played a pivotal role in determining the antibacterial spectrum of AMPs and confirmed that broadening the spectrum could be achieved only by increasing hydrophobicity at certain positions. In conclusion, this research provided a theoretical basis for future precise regulation of an antimicrobial peptide's spectrum by emphasizing the intricate balance between amino acid sites and hydrophobicity.


Assuntos
Anti-Infecciosos , Peptídeos Catiônicos Antimicrobianos , Peptídeos Catiônicos Antimicrobianos/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Aminoácidos/farmacologia , Aminoácidos/química , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana
11.
Int Dent J ; 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38369441

RESUMO

OBJECTIVE: Pulp regeneration with bioactive dentin-pulp complex has been a research hotspot in recent years. Stem cell therapy provided an interest strategy to regenerate the dental-pulp complex. Hence, this study aimed to evaluate the effects of photosensitive gelatin methacrylate (GelMA) hydrogel encapsulating dental pulp stem cells (DPSCs) and silver nanoparticles (AgNPs) for dental pulp regeneration in vitro. METHODS: First, the AgNPs@GelMA hydrogels were prepared by lithium phenyl-2,4,6-trimethyl-benzoyl phosphinate (LAP) initiation via blue-light emitting diode light. The physical and chemical properties of AgNPs@GelMA hydrogels were comprehensively analysed via scanning electron microscopy (SEM), and mechanical characterisation, such as swelling ability, degradation properties, and AgNP release profile. Then, AgNPs@GelMA hydrogels encapsulated DPSCs were used to establish an AgNPs@GelMA biomimetic complex, further analysing its biocompatibility, antibacterial properties, and angiogenic capacity in vitro. RESULTS: The results indicated that GelMA hydrogels demontrated optimal characteristics with a monomer:LAP ratio of 16:1. The physico-chemical properties of AgNPs@GelMA hydrogels did not change significantly after loading with AgNPs. There was no significant difference in AgNP release rate amongst different concentrations of AgNPs@GelMA hydrogels. Fifty to 200 µg/mL AgNPs@GelMA hydrogels could disperse E faecalis biofilm and reduce its metabolic activity . Furthermore, cell proliferation was arrested in 100 and 200 µg/mL AgNPs@GelMA hydrogels. The inhibition of 50 µg/mL AgNPs@GelMA hydrogels on E faecalis biofilm was above 50%, and the cell viability of the hydrogels was higher than 90%. The angiogenesis assay indicated that AgNPs@GelMA hydrogels encapsulating DPSCs could induce the formation of capillary-like structures and express angiogenic markers CD31, vascular endothelial growth factor , and von willebrand factor (vWF) in vitro. CONCLUSIONS: Results of this study indicate that 50 µg/mL AgNPs@GelMA hydrogels encapsulating DPSCs had significant antibacterial properties and angiogenic capacity, which could provide a significant experimental basis for the regeneration of the dentin-pulp complex.

12.
Plant J ; 118(4): 1119-1135, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38308390

RESUMO

Salicylic acid (SA) is known to enhance salt tolerance in plants. However, the mechanism of SA-mediated response to high salinity in halophyte remains unclear. Using electrophysiological and molecular biological methods, we investigated the role of SA in response to high salinity in mangrove species, Kandelia obovata, a typical halophyte. Exposure of K. obovata roots to high salinity resulted in a rapid increase in endogenous SA produced by phenylalanine ammonia lyase pathway. The application of exogenous SA improved the salt tolerance of K. obovata, which depended on the NADPH oxidase-mediated H2O2. Exogenous SA and H2O2 increased Na+ efflux and reduced K+ loss by regulating the transcription levels of Na+ and K+ transport-related genes, thus reducing the Na+/K+ ratio in the salt-treated K. obovata roots. In addition, exogenous SA-enhanced antioxidant enzyme activity and its transcripts, and the expressions of four genes related to AsA-GSH cycle as well, then alleviated oxidative damages in the salt-treated K. obovata roots. However, the above effects of SA could be reversed by diphenyleneiodonium chloride (the NADPH oxidase inhibitor) and paclobutrazol (a SA biosynthesis inhibitor). Collectively, our results demonstrated that SA-induced salt tolerance of K. obovata depends on NADPH oxidase-generated H2O2 that affects Na+/K+ and redox homeostasis in response to high salinity.


Assuntos
Homeostase , Peróxido de Hidrogênio , NADPH Oxidases , Oxirredução , Raízes de Plantas , Potássio , Ácido Salicílico , Tolerância ao Sal , Sódio , Peróxido de Hidrogênio/metabolismo , NADPH Oxidases/metabolismo , NADPH Oxidases/genética , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacologia , Potássio/metabolismo , Tolerância ao Sal/genética , Sódio/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Raízes de Plantas/metabolismo , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/metabolismo , Plantas Tolerantes a Sal/fisiologia , Regulação da Expressão Gênica de Plantas , Rhizophoraceae/fisiologia , Rhizophoraceae/genética , Rhizophoraceae/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Epilepsy Behav Rep ; 25: 100640, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38235017

RESUMO

The management of epilepsy during pregnancy presents particular challenges for neurologists worldwide. Currently, there are no clear recommendations for oxcarbazepine (OXC) specific target concentration during pregnancy. We conducted this retrospective observational cohort study on pregnant women with epilepsy (WWE) who received OXC monotherapy or polytherapy, at the epilepsy outpatient clinic of a tertiary hospital in eastern China. Sixteen pregnancies of 16 WWE were split into the seizure-free group or the non-seizure-free group, according to whether they had been seizure free for more than one year prior to conception or not. There was a significantly decrease in OXC concentration throughout pregnancy, as indicated by the concentration/dose ratio and the ratio of target concentration (RTC). The second trimester of pregnancy was the period when seizure deterioration occurred the most, particularly in the non-seizure-free group. Lower RTC_OXC was identified to be a risk factor for increasing seizure frequency in both the total group and the non-seizure-free group in both univariate and multivariate analysis, with a threshold of 0.575 for differentiating patients at high-risk and low-risk for seizure deterioration. In conclusion, this study suggested an OXC concentration threshold of 0.575 during pregnancy for assisting neurologists in OXC drug monitoring and dose adaptation.

14.
Appl Microbiol Biotechnol ; 108(1): 56, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38175241

RESUMO

Antifungal peptides (AFPs) can be used as novel preservatives, but achieving large-scale production and application remains a long-term challenge. In this study, we developed a hybrid peptide MD (metchnikowin-drosomycin fusion) secreted into Escherichia coli supernatant, demonstrating strong inhibitory activity against Aspergillus flavus and Botrytis cinerea. The fusion tag did not impact its activity. Moreover, an endotoxin-free and oxidative leaky strain was developed by knocking out the trxB, gor, and lpp genes of endotoxin-free E. coli ClearColi-BL21(DE3). This strain facilitates the proper folding of multi-disulfide bond proteins and promotes the extracellular production of recombinant bioactive AFP MD, achieving efficient production of endotoxin-free MD. In addition, temperature control replaces chemical inducers to further reduce production costs and circumvent the toxicity of inducers. This extracellularly produced MD exhibited favorable effectiveness in inhibiting fruit mold growth, and its safety was preliminarily established by gavage testing in mice, suggesting that it can be developed into a green and sustainable fruit fungicide. In conclusion, this study provides novel approaches and systematic concepts for producing extracellularly active proteins or peptides with industrial significance. KEY POINTS: • First report of extracellular production of bioactive antifungal peptide in Escherichia coli. • The hybrid antifungal peptide MD showed strong inhibitory activity against Aspergillus flavus and Botrytis cinerea, and the activity was not affected by the fusion tag. • Endotoxin-free oxidative Escherichia coli suitable for the expression of multi-disulfide bond proteins was constructed.


Assuntos
Antifúngicos , Escherichia coli , Animais , Camundongos , Antifúngicos/farmacologia , Escherichia coli/genética , Peptídeos/farmacologia , Aspergillus flavus/genética , Endotoxinas/genética , Dissulfetos , Estresse Oxidativo
15.
J Biotechnol ; 381: 19-26, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38181981

RESUMO

The antimicrobial peptide (AMP) LI is a fusion product of antimicrobial peptide LL37 produced by human neutrophils and Indolicidin secreted by bovine neutrophils. LI retained the antimicrobial activity of the parental peptides and showed high cell selectivity. In this study, the flexible linker Gly-Ser-Gly (G-S-G) was used to ligate LI into dimeric LIG, and constructed the Pichia pastoris (P. pastoris) expression vector pPIC9K-6×His-3×FLAG-LIG. The total protein expression of P. pastoris GS115 reached the highest level (189.6 mg/L) after 96 h induction with 3 % methanol at the initial pH value of 7.0. Finally, 5.9 mg/L of recombinant LIG (rLIG) was obtained after enterokinase digestion and purification. The rLIG had high antimicrobial activity and low hemolytic activity. Compared with monomer LI, GSG linked dimeric LIG, which had no significant change in antimicrobial activity and had good salt ions stability. In this study, the dimeric antimicrobial peptide LIG was successfully expressed, which provided a new idea for the expression of AMPs in the P. pastoris expression system, and had important significance for the application of AMPs.


Assuntos
Anti-Infecciosos , Saccharomycetales , Animais , Bovinos , Humanos , Peptídeos Antimicrobianos , Pichia/metabolismo , Anti-Infecciosos/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
16.
Mikrochim Acta ; 191(2): 108, 2024 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-38244133

RESUMO

Microcystin LR (MC-LR) is a hazardous cyanotoxin produced by cyanobacteria during freshwater eutrophication, which can cause liver cancer. Here, a photoelectrochemical (PEC) aptasensor based on methylene blue (MB)-loaded Ni-MOF composite (Ni-MOF/MB) with spatial confinement was constructed for the sensitive detection of MC-LR. Ni-MOF with two-dimensional sheet structure was prepared via a liquid-liquid interface synthesis method with environmental-friendly solvent and milder reaction conditions. Benefiting from the uniform pore size, Ni-MOF acted as reaction platform to anchor the photosensitive molecule MB. The electron donor, ascorbic acid (AA), was produced by alkaline phosphatase (ALP) loaded on DNA strand catalyzing ascorbic acid phosphate. The generated AA was absorbed by Ni-MOF/MB, thereby effectively improving the utilization of AA and avoiding the external environment interferences to enlarge the photocurrent of MB. For analysis, ALP-labeled aptamer can specifically recognize MC-LR by forming a complex to strip from aptasensor, thus leading to a  decreased photocurrent. The developed PEC aptasensor offered a linear range of 10 fM-100 pM with a detection limit of 6 fM. It was successfully employed for detecting MC-LR in farm water and fish meat, and the results were validated by ultrahigh-performance liquid chromatography-mass spectrometry. This method presents a new idea of MOF-limited domain for PEC aptasensing.


Assuntos
Aptâmeros de Nucleotídeos , Toxinas Marinhas , Microcistinas , Nanocompostos , Animais , Azul de Metileno/química , Técnicas Eletroquímicas , Aptâmeros de Nucleotídeos/química , Ácido Ascórbico
17.
Anal Chem ; 96(6): 2582-2589, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38294965

RESUMO

The Janus interface, comprising multiple functional heterointerfaces with contrasting functionalities within a single interface, has recently garnered widespread research interest. Herein, a Janus biosensing interface is obtained via wavelength-resolved laser illumination. Deoxyribonucleic acid bridges the electrochemical probe of methylene blue (MB) and plasmonic gold nanoparticles (AuNPs), achieving a sensitive detection performance. MB shows differential electrochemical signals under front (I532front) and back (I650back) laser illumination at 532 and 650 nm, respectively, owing to the selective wavelength-resolved effect. Thus, the presence of a wavelength-resolved laser enabled the design of a biosensing interface with Janus properties. The change in the distance between MB and AuNPs induced by aflatoxin B1 (AFB1) indicates that a sensitive response of the Janus biosensing interface can be achieved. A ratiometric strategy is introduced to describe the electrochemical signals of the I532front and I650back for improved robustness. The obtained linear range is 0.0005-50 ng mL-1, with a detection limit of 0.175 pg mL-1. Our study demonstrated that the wavelength-resolved Janus interface enables an electrochemical biosensor with excellent sensitivity. This finding provides an efficient approach for improving biosensor performance.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro/química , Técnicas Eletroquímicas , Nanopartículas Metálicas/química , Luz , Aflatoxina B1/análise , Azul de Metileno/química , Limite de Detecção , Aptâmeros de Nucleotídeos/química
18.
J Biochem Mol Toxicol ; 38(1): e23538, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37706587

RESUMO

Oleanolic acid (OA) is a natural triterpenoid with therapeutic potential for a multitude of diseases. However, the precise mechanism by which OA influences stress-induced apoptosis of intestinal epithelial cells remains elusive. Therefore, the effect of OA on intestinal diseases under stressful conditions and its possible mechanisms have been investigated. In a hydrogen peroxide (H2 O2 )-induced oxidative stress model, OA attenuated H2 O2 -induced apoptosis in a concentration-dependent manner. To investigate the underlying mechanisms, the gene expression profile of OA on IPEC-J2 cells was analyzed using an RNA sequencing system. Results from gene ontology and Kyoto encyclopedia of genes and genomes analysis confirmed that OA may mitigate the cytotoxic effects of H2 O2 by downregulating gene expression through the MAPK signaling pathway. Furthermore, Quantitative real-time polymerase chain reaction results validated the differentially expressed genes data. Western blot analysis further demonstrated that OA effectively suppressed the expression level of c-Jun protein induced by H2 O2 in IPEC-J2 cells. Collectively, our results indicate that OA pretreatment significantly attenuated H2 O2 -induced apoptosis in intestinal epithelial cells through suppressing c-Jun and MAPK pathway.


Assuntos
Peróxido de Hidrogênio , Ácido Oleanólico , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Ácido Oleanólico/farmacologia , Linhagem Celular , Apoptose , Estresse Oxidativo , Células Epiteliais/metabolismo
19.
J Agric Food Chem ; 72(1): 27-45, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37964463

RESUMO

The intestinal barrier is critical for maintaining intestinal homeostasis, and its dysfunction is associated with various diseases. Recent findings have revealed the multifunctional role of intestinal alkaline phosphatase (IAP) in diverse biological processes, including gut health maintenance and function. This review summarizes the protective effects of IAP on intestinal barrier integrity, encompassing the physical, chemical, microbial, and immune barriers. We discuss the results and insights from in vitro, animal model, and clinical studies as well as the available evidence regarding the impact of diet on IAP activity and expression. IAP can also be used as an indicator to assess intestinal-barrier-related diseases. Further research into the mechanisms of action and long-term health effects of IAP in maintaining overall intestinal health is essential for its future use as a dietary supplement or functional component in medical foods.


Assuntos
Fosfatase Alcalina , Mucosa Intestinal , Animais , Mucosa Intestinal/metabolismo , Fosfatase Alcalina/metabolismo , Dieta , Suplementos Nutricionais
20.
Ann Lab Med ; 44(3): 245-252, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38014482

RESUMO

Background: Clinical chemistry tests are most widely used in clinical laboratories, and diverse measurement systems for these analyses are available in China. We evaluated the imprecision of clinical chemistry measurement systems based on internal QC (IQC) data. Methods: IQC data for 27 general chemistry analytes were collected in February each year from 2013 to 2022. Four performance specifications were used to calculate pass rates for CVs of IQC data in 2022. Boxplots were drawn to analyze trends of CVs, and differences in CVs among different groups were assessed using the Mann-Whitney U-test or Kruskal-Wallis test. Results: The number of participating laboratories increased significantly from 1,777 in 2013 to 5,425 in 2022. CVs significantly decreased for all 27 analytes, except creatine kinase and lipase. Triglycerides, total bilirubin, direct bilirubin, iron, and γ-glutamyl transferase achieved pass rates >80% for all goals. Nine analytes with pass rates <80% based on 1/3 allowable total error were further analyzed; the results indicated that closed systems exhibited lower CVs than open systems for all analytes, except total protein. For all nine analytes, differences were significant between tertiary hospitals and non-tertiary hospitals and between accredited and non-accredited laboratories. Conclusions: The CVs of IQC data for clinical chemistry have seen a continuous overall improvement in China. However, there is ample room for imprecision improvement for several analytes, with stricter performance specifications.


Assuntos
Serviços de Laboratório Clínico , Laboratórios , Humanos , Controle de Qualidade , Testes de Química Clínica , Bilirrubina , China , Química Clínica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...