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1.
Parasit Vectors ; 17(1): 202, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711138

RESUMEN

BACKGROUND: The Lone Star tick, Amblyomma americanum is important to human health because of a variety of pathogenic organisms transmitted to humans during feeding events, which underscores the need to identify novel approaches to prevent tick bites. Thus, the goal of this study was to test natural and synthetic molecules for repellent activity against ticks in spatial, contact and human fingertip bioassays. METHODS: The efficacy of essential oils and naturally derived compounds as repellents to Am. americanum nymphs was compared in three different bioassays: contact, spatial and fingertip repellent bioassays. RESULTS: Concentration response curves after contact exposure to 1R-trans-chrysanthemic acid (TCA) indicated a 5.6 µg/cm2 concentration required to repel 50% of ticks (RC50), which was five- and sevenfold more active than DEET and nootkatone, respectively. For contact repellency, the rank order of repellency at 50 µg/cm2 for natural oils was clove > geranium > oregano > cedarwood > thyme > amyris > patchouli > citronella > juniper berry > peppermint > cassia. For spatial bioassays, TCA was approximately twofold more active than DEET and nootkatone at 50 µg/cm2 but was not significantly different at 10 µg/cm2. In spatial assays, thyme and cassia were the most active compounds tested with 100% and 80% ticks repelled within 15 min of exposure respectively and was approximately twofold more effective than DEET at the same concentration. To translate these non-host assays to efficacy when used on the human host, we quantified repellency using a finger-climbing assay. TCA, nootkatone and DEET were equally effective in the fingertip assay, and patchouli oil was the only natural oil that significantly repelled ticks. CONCLUSIONS: The differences in repellent potency based on the assay type suggests that the ability to discover active tick repellents suitable for development may be more complicated than with other arthropod species; furthermore, the field delivery mechanism must be considered early in development to ensure translation to field efficacy. TCA, which is naturally derived, is a promising candidate for a tick repellent that has comparable repellency to commercialized tick repellents.


Asunto(s)
Amblyomma , Aceites Volátiles , Animales , Aceites Volátiles/farmacología , Aceites Volátiles/química , Amblyomma/efectos de los fármacos , Repelentes de Insectos/farmacología , Humanos , Aceites de Plantas/farmacología , Aceites de Plantas/química , Ninfa/efectos de los fármacos , Bioensayo , DEET/farmacología
2.
Microbiologyopen ; 13(3): e1411, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38706434

RESUMEN

Traditional bacteriocin screening methods often face limitations due to diffusion-related challenges in agar matrices, which can prevent the peptides from reaching their target organism. Turbidimetric techniques offer a solution to these issues, eliminating diffusion-related problems and providing an initial quantification of bacteriocin efficacy in producer organisms. This study involved screening the cell-free supernatant (CFS) from eight uncharacterized asymptomatic bacteriuria (ABU) isolates and Escherichia coli 83972 for antimicrobial activity against clinical uropathogenic E. coli (UPEC) strains using turbidimetric growth methods. ABU isolates exhibiting activity against five or more UPEC strains were further characterized (PUTS 37, PUTS 58, PUTS 59, S-07-4, and SK-106-1). The inhibition of the CFS by proteinase K suggested that the antimicrobial activity was proteinaceous in nature, potentially bacteriocins. The activity of E. coli PUTS 58 and SK-106-1 was enhanced in an artificial urine medium, with both inhibiting all eight UPECs. A putative microcin H47 operon was identified in E. coli SK-106-1, along with a previously identified microcin V and colicin E7 in E. coli PUTS 37 and PUTS 58, respectively. These findings indicate that ABU bacteriocin-producers could serve as viable prophylactics and therapeutics in the face of increasing antibiotic resistance among uropathogens.


Asunto(s)
Bacteriuria , Infecciones por Escherichia coli , Escherichia coli Uropatógena , Escherichia coli Uropatógena/efectos de los fármacos , Escherichia coli Uropatógena/genética , Bacteriuria/microbiología , Humanos , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/tratamiento farmacológico , Bacteriocinas/farmacología , Bacteriocinas/genética , Nefelometría y Turbidimetría , Bioensayo/métodos , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Infecciones Urinarias/microbiología
3.
J Agric Food Chem ; 72(19): 10958-10969, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703118

RESUMEN

Demand for the exploration of botanical pesticides continues to increase due to the detrimental effects of synthetic chemicals on human health and the environment and the development of resistance by pests. Under the guidance of a bioactivity-guided approach and HSQC-based DeepSAT, 16 coumarin derivatives were discovered from the leaves of Ailanthus altissima (Mill.) Swingle, including seven undescribed monoterpenoid coumarins, three undescribed monoterpenoid phenylpropanoids, and two new coumarin derivatives. The structure and configurations of these compounds were established and validated via extensive spectroscopic analysis, acetonide analysis, and quantum chemical calculations. Biologically, 5 exhibited significant antifeedant activity toward the Plutella xylostella. Moreover, tyrosinase being closely related to the growth and development of larva, the inhibitory potentials of 5 against tyrosinase was evaluated in vitro and in silico. The bioactivity evaluation results highlight the prospect of 5 as a novel category of botanical insecticide.


Asunto(s)
Ailanthus , Cumarinas , Insecticidas , Extractos Vegetales , Hojas de la Planta , Hojas de la Planta/química , Animales , Cumarinas/farmacología , Cumarinas/química , Ailanthus/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Insecticidas/química , Insecticidas/farmacología , Estructura Molecular , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/crecimiento & desarrollo , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Bioensayo , Monoterpenos/farmacología , Monoterpenos/química , Conducta Alimentaria/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química
4.
Luminescence ; 39(5): e4776, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38769690

RESUMEN

The purpose of the work was to find optimal conditions for bioluminescent enzymatic analysis of saliva (based on the use of NADH:FMN oxidoreductase + luciferase) and then to determine the biological effect of using bioluminescence assay of saliva to study the physiological state of the body under normal and pathological conditions. The saliva of snowboarders and students were studied in the "rest-training" model. The saliva of patients diagnosed with acute pharyngitis was examined in the "sick-healthy" model. Bioluminescence assay was performed with a lyophilized and immobilized bi-enzyme system using cuvette, plate, and portable luminometers. The concentrations of secretory immunoglobulin A (sIgA) and cortisol were determined by enzyme immunoassay, and the total protein content was measured by spectrophotometric method. The activity of the bioluminescent system enzymes increased as the amount and volume of saliva in the sample was decreased. The cuvette and plate luminometers were sensitive to changes in the luminescence intensity in saliva assay. Luminescence intensity correlated with the concentrations of sIgA and cortisol. The integrated bioluminescent index for saliva was reduced in the "rest-training" model and increased in the "sick-healthy" model. Thus, the non-invasive bioluminescent saliva analysis may be a promising tool for assessing the health of the population.


Asunto(s)
Mediciones Luminiscentes , Saliva , Humanos , Saliva/enzimología , Saliva/química , Mediciones Luminiscentes/métodos , Bioensayo , Hidrocortisona/análisis , Hidrocortisona/metabolismo , Luciferasas/metabolismo , Luciferasas/química , Inmunoglobulina A Secretora/análisis , Inmunoglobulina A Secretora/metabolismo
5.
J Pharm Biomed Anal ; 245: 116185, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38723556

RESUMEN

Human epidermal growth factor receptor 2 (HER2) is a key player in the pathogenesis and progression of breast cancer and is currently a primary target for breast cancer immunotherapy. Bioactivity determination is necessary to guarantee the safety and efficacy of therapeutic antibodies targeting HER2. Nevertheless, currently available bioassays for measuring the bioactivity of anti-HER2 mAbs are either not representative or have high variability. Here, we established a reliable reporter gene assay (RGA) based on T47D-SRE-Luc cell line that expresses endogenous HER2 and luciferase controlled by serum response element (SRE) to measure the bioactivity of anti-HER2 antibodies. Neuregulin-1 (NRG-1) can lead to the heterodimerization of HER2 on the cell membrane and induce the expression of downstream SRE-controlled luciferase, while pertuzumab can dose-dependently reverse the reaction, resulting in a good dose-response curve reflecting the activity of the antibody. After optimizing the relevant assay parameters, the established RGA was fully validated based on ICH-Q2 (R1), which demonstrated that the method had excellent specificity, accuracy, precision, linearity, and stability. In summary, this robust and innovative bioactivity determination assay can be applied in the development and screening, release control, biosimilar assessment and stability studies of anti-HER2 mAbs.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Bioensayo , Genes Reporteros , Luciferasas , Neurregulina-1 , Receptor ErbB-2 , Receptor ErbB-2/genética , Receptor ErbB-2/inmunología , Receptor ErbB-2/antagonistas & inhibidores , Humanos , Línea Celular Tumoral , Anticuerpos Monoclonales Humanizados/farmacología , Bioensayo/métodos , Luciferasas/genética , Neurregulina-1/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/genética , Femenino , Antineoplásicos Inmunológicos/farmacología , Reproducibilidad de los Resultados , Elementos de Respuesta
6.
Exp Parasitol ; 261: 108763, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38704016

RESUMEN

The brown dog tick or Rhipicephalus sanguineus sensu lato is an ixodid tick, responsible for the dissemination of pathogens that cause canine infectious diseases besides inflicting the direct effects of tick bite. The hot humid climate of Kerala, a south Indian state, is favorable for propagation of tick vectors and acaricides are the main stay of tick control. Though the resistance against synthetic pyrethroids is reported among these species, the status of amitraz resistance in R. sanguineus s. l. in the country is uncertain due to the lack of molecular characterisation data and scarce literature reports. Hence the present study was focused on the phenotypic detection and preliminary genotypic characterisation of amitraz resistance in the R. sanguineus s. l. A modified larval packet test (LPT) on a susceptible isolate was performed to determine the discriminating dose (DD). Further LPT-DD on 35 tick isolates was carried out to detect amitraz resistance robustly, along with that full dose response bioassays on the resistant isolates were performed. The results indicated that amitraz resistance is prevalent with 49 per cent of the samples being resistant. Amplification of exon 3 of octopamine receptor gene from both the susceptible and resistant larval isolates was carried out. Amplicons of ten pooled amitraz susceptible and ten pooled amitraz resistant representative samples were sequenced and analysed, unveiling a total of three novel non-synonymous mutations in the partial coding region at positions V32A, N41D and V58I in phenotypically resistant larval DNA samples. In silico analysis by homology modelling and molecular docking of the mutated and unmutated receptors showed that these mutations had reduced the binding affinity to amitraz. However, lack of mutations in the octopamine receptor gene in three of the pooled low order resistant R. sanguineus s. l. larval samples could be suggestive of other mechanisms associated with amitraz resistance in the region. Hence, further association studies should be carried out to confirm the association of these mutations with target insensitivity in R. sanguineus s. l. ticks, along with exploring the status of metabolic resistance and other mechanisms of resistance.


Asunto(s)
Acaricidas , Receptores de Amina Biogénica , Rhipicephalus sanguineus , Toluidinas , Animales , Toluidinas/farmacología , Receptores de Amina Biogénica/genética , India , Rhipicephalus sanguineus/genética , Rhipicephalus sanguineus/efectos de los fármacos , Acaricidas/farmacología , Larva/genética , Larva/efectos de los fármacos , Resistencia a los Insecticidas/genética , Polimorfismo Genético , Genotipo , Perros , Femenino , Enfermedades de los Perros/parasitología , Simulación del Acoplamiento Molecular , Secuencia de Aminoácidos , Bioensayo
7.
Sci Total Environ ; 931: 172718, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38677438

RESUMEN

Wastewater treatment plants (WWTP) are facilities where municipal wastewater undergoes treatment so that its organic load and its pathogenic potential are minimized. Sewage sludge is a by-product of this process and when properly treated is preferentially called "biosolids". These treatments may include some or most of the following: thickening, dewatering, drying, digestion, composting, liming. Nowadays it is almost impossible to landfill biosolids, which however can well be used as crop fertilizers. Continuous or superfluous biosolids fertilization may negatively affect non-target organisms such as soil macro-organisms or even plants. These effects can be depicted through bioassays on terrestrial animals and plants. It has been shown that earthworms have been affected to various degrees on the following endpoints: pollutants' bioaccumulation, viability, reproduction, avoidance behavior, burrowing behavior. Collembola have been affected on viability, reproduction, avoidance behavior. Other terrestrial organisms such as nematodes and diplopods have also shown adverse health effects. Phytotoxicity have been caused by some biosolids regimes as measured through the following endpoints: seed germination, root length, shoot length, shoot biomass, root biomass, chlorophyll content, antioxidant enzyme activity. Very limited statistical correlations between pollutant concentrations and toxicity endpoints have been established such as between juvenile mortality (earthworms) and As or Ba concentration in the biosolids, between juvenile mortality (collembola) and Cd or S concentration in the biosolids, or between phytotoxicity and some extractable metals in leachates or aquatic extracts from the biosolids; more correlations between physicochemical characteristics and toxicity endpoints have been found such as between phytotoxicity and ammonium N in biosolids or their liquid extracts, or between phytotoxicity and salinity. An inverse correlation between earthworm/collembola mortality and stable organic matter has also been found. Basing the appropriateness of biosolids only on chemical analyses for pollutants is not cost-effective. To enable risk characterization and subsequent risk mitigation it is important to apply a battery of bioassays on soil macro-organisms and on plants, utilizing a combination of endpoints and established protocols. Through combined analytical quantification and toxicity testing, safe use of biosolids in agriculture can be achieved.


Asunto(s)
Bioensayo , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Aguas del Alcantarillado/química , Animales , Oligoquetos/efectos de los fármacos , Oligoquetos/fisiología , Fertilizantes , Plantas/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Pruebas de Toxicidad , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/toxicidad
8.
J Cell Mol Med ; 28(8): e18275, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38568058

RESUMEN

Breast cancer (BC) remains a significant health concern worldwide, with metastasis being a primary contributor to patient mortality. While advances in understanding the disease's progression continue, the underlying mechanisms, particularly the roles of long non-coding RNAs (lncRNAs), are not fully deciphered. In this study, we examined the influence of the lncRNA LINC00524 on BC invasion and metastasis. Through meticulous analyses of TCGA and GEO data sets, we observed a conspicuous elevation of LINC00524 expression in BC tissues. This increased expression correlated strongly with a poorer prognosis for BC patients. A detailed Gene Ontology analysis suggested that LINC00524 likely exerts its effects through RNA-binding proteins (RBPs) mechanisms. Experimentally, LINC00524 was demonstrated to amplify BC cell migration, invasion and proliferation in vitro. Additionally, in vivo tests showed its potent role in promoting BC cell growth and metastasis. A pivotal discovery was LINC00524's interaction with TDP43, which leads to the stabilization of TDP43 protein expression, an element associated with unfavourable BC outcomes. In essence, our comprehensive study illuminates how LINC00524 accelerates BC invasion and metastasis by binding to TDP43, presenting potential avenues for therapeutic interventions.


Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Femenino , Humanos , Bioensayo , Neoplasias de la Mama/genética , Transformación Celular Neoplásica , Ontología de Genes , ARN Largo no Codificante/genética
9.
Appl Microbiol Biotechnol ; 108(1): 284, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38573322

RESUMEN

SELEX (Systematic Evolution of Ligands by Exponential enrichment) processes aim on the evolution of high-affinity aptamers as binding entities in diagnostics and biosensing. Aptamers can represent game-changers as constituents of diagnostic assays for the management of instantly occurring infectious diseases or other health threats. Without in-process quality control measures SELEX suffers from low overall success rates. We present a quantitative PCR method for fast and easy quantification of aptamers bound to their targets. Simultaneous determination of melting temperatures (Tm) of each SELEX round delivers information on the evolutionary success via the correlation of increasing GC content and Tm alone with a round-wise increase of aptamer affinity to the respective target. Based on nine successful and published previous SELEX processes, in which the evolution/selection of aptamer affinity/specificity was demonstrated, we here show the functionality of the IMPATIENT-qPCR for polyclonal aptamer libraries and resulting individual aptamers. Based on the ease of this new evolution quality control, we hope to introduce it as a valuable tool to accelerate SELEX processes in general. IMPATIENT-qPCR SELEX success monitoring. Selection and evolution of high-affinity aptamers using SELEX technology with direct aptamer evolution monitoring using melting curve shifting analyses to higher Tm by quantitative PCR with fluorescence dye SYBR Green I. KEY POINTS: • Fast and easy analysis. • Universal applicability shown for a series of real successful projects.


Asunto(s)
Bioensayo , Oligonucleótidos , Control de Calidad , Temperatura
10.
Microb Biotechnol ; 17(4): e14444, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38564168

RESUMEN

Assisted reproductive techniques are routinely used in livestock species to increase and enhance productivity. Ovarian hyperstimulation is a process that currently relies on administering pituitary-derived follicle-stimulating hormone (FSH) or equine chorionic gonadotropin in combination with other hormones to promote the maturation of multiple follicles and thereby achieve superovulation. The use of partially purified preparations of FSH extracted from natural sources is associated with suboptimal and variable results. Recombinant FSH (rFSH) has been produced in a variety of heterologous organisms. However, attaining a bioactive rFSH of high quality and at low cost for use in livestock remains challenging. Here we report the production and characterization of a single chain bovine rFSH consisting of the ß- and α-subunit fused by a polypeptide linker (scbFSH) using Leishmania tarentolae as heterologous expression system. This unicellular eukaryote is non-pathogenic to mammals, can be grown in bioreactors using simple and inexpensive semisynthetic media at 26°C and does not require CO2 or bovine serum supplementation. Stable cell lines expressing scbFSH in an inducible fashion were generated and characterized for their productivity. Different culture conditions and purification procedures were evaluated, and the recombinant product was biochemically and biologically characterized, including bioassays in an animal model. The results demonstrate that L. tarentolae is a suitable host for producing a homogeneous, glycosylated and biologically active form of scbFSH with a reasonable yield.


Asunto(s)
Leishmania , Femenino , Animales , Caballos , Leishmania/genética , Bioensayo , Reactores Biológicos , Línea Celular , Hormona Folículo Estimulante , Mamíferos
11.
PLoS One ; 19(4): e0290753, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38598542

RESUMEN

Metabolic reprogramming has been defined as a hallmark of malignancies. Prior studies have focused on the single nucleotide polymorphism (SNP) of POLG2 gene, which is reportedly responsible for encoding mitochondrial DNA genes and is implicated in the material and energy metabolism of tumor cells, whereas its function in prostate cancer has been elusive. Gene expression profile matrix and clinical information were downloaded from TCGA (The Cancer Genome Atlas) data portal, and GSE3325 and GSE8511 were retrieved from GEO (Gene Expression Omnibus) database. We conducted analysis of the relative expression of POLG2, clinical characterization, survival analysis, GO / KEGG and GSEA (Gene Set Enrichment Analysis) enrichment analysis in R and employed STRING portal to acquaint ourselves with the protein-protein interaction (PPI). IHC (Immunohistochemical) profiles of POLG2 protein between normal and cancerous tissues were consulted via HPA (Human protein atlas) database and the immunohistochemical POLG2 were verified between para-cancerous and cancerous tissues in tissue array. At the cellular level, Mitochondrial dysfunction assay, DNA synthesis test, wound healing assay, and invasion assay were implemented to further validate the phenotype of POLG2 knockdown in PCa cell lines. RT-qPCR and western blotting were routinely adopted to verify variations of molecular expression within epithelial mesenchymal transition (EMT). Results showed that POLG2 was over-expressed in most cancer types, and the over-expression of POLG2 was correlated with PCa progression and suggested poor OS (Overall Survival) and PFI (Progress Free Interval). Multivariate analysis showed that POLG2 might be an independent prognostic factor of prostate cancer. We also performed GO/KEGG, GSEA analysis, co-expression genes, and PPI, and observed the metabolism-related gene alterations in PCa. Furthermore, we verified that POLG2 knockdown had an inhibitory effect on mitochondrial function, proliferation, cell motility, and invasion, we affirmed POLG2 could affect the prognosis of advanced prostate cancer via EMT. In summary, our findings indicate that over-expressed POLG2 renders poor prognosis in advanced prostate cancer. This disadvantageous factor can serve as a potential indicator, making it possible to target mitochondrial metabolism to treat advanced prostate cancer.


Asunto(s)
Neoplasias de la Próstata , Humanos , Masculino , Neoplasias de la Próstata/genética , Mitocondrias/genética , Metabolismo Energético , ADN Mitocondrial , Bioensayo
12.
Methods Mol Biol ; 2794: 305-311, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38630239

RESUMEN

Brain defects often lead to motor dysfunctions in humans. Drosophila melanogaster has been one of the most useful organisms in the study of neuronal biology due to its similarities with humans and has contributed to a more detailed understanding of the effects of genetic dysfunctions in the brain on behavior. We herein present modified protocols for the crawling assay with larvae and the climbing assay with adult flies that are simple to perform as well as a series of commands for ImageJ to automatically analyze data for the crawling assay.


Asunto(s)
Artrópodos , Drosophila , Adulto , Humanos , Animales , Larva , Drosophila melanogaster , Bioensayo
13.
Methods Mol Biol ; 2794: 321-330, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38630241

RESUMEN

Behavioral plasticity is subjected to various sensory stimuli, experiences, and physiological states, representing the temporal and spatial patterns of neural circuit dynamics. Elucidation of how genes and neural circuits in our brain actuate behavioral plasticity requires functional imaging during behavioral assays to manifest temporal and spatial neural regulation in behaviors. The exploration of the nervous systems of Caenorhabditis elegans has catalyzed substantial scientific advancements in elucidating the mechanistic link between circuit dynamics and behavioral plasticity. The analyses of the nervous system of C. elegans have technologically flourished owing to the development of optogenetic instruments and fluorescent protein-based imaging compatible with its optically transparent body and the understanding of its completely revealed neural connectome and gene expression profiles at single-neuron resolution (The C. elegans Neuronal Gene Expression Map & Network, CeNGEN project). Using examples of the two temperature learning behaviors in C. elegans, this chapter delves into a selection of pivotal imaging tools, including genetically encoded calcium indicators, biosensors for second messenger imaging, and their usage in freely moving worms that have propelled our grasp of sensory representation in C. elegans neural circuits. To further connect the circuit dynamics to behavioral plasticity, this chapter will focus on technological advancements enabling simultaneous imaging and tracking system together with methodologies to quantify multiple behavioral elements of freely behaving C. elegans in a dynamic environment.


Asunto(s)
Encéfalo , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Neuronas , Bioensayo , Mapeo Cromosómico
14.
Sci Total Environ ; 927: 172199, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38580108

RESUMEN

Effect-directed analysis (EDA) is a crucial tool in environmental toxicology, effectively integrating toxicity testing with chemical analysis. The conventional EDA approach, however, presents challenges such as significant solvent consumption, extended analysis time, labor intensity, and potential contamination risks. In response, we introduce an innovative alternative to the conventional EDA. This method utilizes the MTT bioassay and online two-dimensional liquid chromatography (2D LC) coupled with high-resolution mass spectrometry (HR-MS), significantly reducing the fractionation steps and leveraging the enhanced sensitivity of the bioassay and automated chemical analysis. In the chemical analysis phase, a switching valve interface is employed for comprehensive analysis. We tested the performance of both the conventional and our online 2D LC-based methods using a household product. Both methods identified the same number of toxicants in the sample. Our alternative EDA is 22.5 times faster than the conventional method, fully automated, and substantially reduces solvent consumption. This novel approach offers ease, cost-effectiveness, and represents a paradigm shift in EDA methodologies. By integrating a sensitive bioassay with online 2D LC, it not only enhances efficiency but also addresses the challenges associated with traditional methods, marking a significant advancement in environmental toxicology research.


Asunto(s)
Contaminantes Ambientales , Cromatografía Liquida/métodos , Contaminantes Ambientales/toxicidad , Contaminantes Ambientales/análisis , Pruebas de Toxicidad/métodos , Monitoreo del Ambiente/métodos , Espectrometría de Masas/métodos , Bioensayo/métodos , Ecotoxicología/métodos
15.
Molecules ; 29(7)2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38611733

RESUMEN

The process of blood coagulation, wherein circulating blood transforms into a clot in response to an internal or external injury, is a critical physiological mechanism. Monitoring this coagulation process is vital to ensure that blood clotting neither occurs too rapidly nor too slowly. Anticoagulants, a category of medications designed to prevent and treat blood clots, require meticulous monitoring to optimise dosage, enhance clinical outcomes, and minimise adverse effects. This review article delves into the various stages of blood coagulation, explores commonly used anticoagulants and their targets within the coagulation enzyme system, and emphasises the electrochemical methods employed in anticoagulant testing. Electrochemical sensors for anticoagulant monitoring are categorised into two types. The first type focuses on assays measuring thrombin activity via electrochemical techniques. The second type involves modified electrode surfaces that either directly measure the redox behaviours of anticoagulants or monitor the responses of standard redox probes in the presence of these drugs. This review comprehensively lists different electrode compositions and their detection and quantification limits. Additionally, it discusses the potential of employing a universal calibration plot to replace individual drug-specific calibrations. The presented insights are anticipated to significantly contribute to the sensor community's efforts in this field.


Asunto(s)
Anticoagulantes , Coagulación Sanguínea , Anticoagulantes/uso terapéutico , Bioensayo , Calibración , Trombina
16.
Molecules ; 29(7)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38611786

RESUMEN

Membrane-based sensors (MePSs) exhibit remarkable precision and sensitivity in detecting pressure changes. MePSs are commonly used to monitor catalytic reactions in solution, generating gas products crucial for signal amplification in bioassays. They also allow for catalyst quantification by indirectly measuring the pressure generated by the gaseous products. This is particularly interesting for detecting enzymes in biofluids associated with disease onset. To enhance the performance of a MePS, various structural factors influence membrane flexibility and response time, ultimately dictating the device's pressure sensitivity. In this study, we fabricated MePSs using polydimethylsiloxane (PDMS) and investigated how structural modifications affect the Young's modulus (E) and residual stress (σ0) of the membranes. These modifications have a direct impact on the sensors' sensitivity to pressure variations, observed as a function of the volume of the chamber (Σ) or of the mechanical properties of the membrane itself (S). MePSs exhibiting the highest sensitivities were then employed to detect catalyst quantities inducing the dismutation of hydrogen peroxide, producing dioxygen as a gaseous product. As a result, a catalase enzyme was successfully detected using these optimized MePSs, achieving a remarkable sensitivity of (22.7 ± 1.2) µm/nM and a limit of detection (LoD) of 396 pM.


Asunto(s)
Bioensayo , Gases , Catalasa , Membranas , Catálisis , Módulo de Elasticidad
17.
Molecules ; 29(7)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38611964

RESUMEN

Two new phenylspirodrimanes, stachybotrins K and L (1 and 2), together with eight known analogues (3-10), were isolated from deep-sea-derived Stachybotrys sp. MCCC 3A00409. Their structures were determined by extensive NMR data and mass spectroscopic analysis. Absolute configurations of new compounds were determined through a comparison of their circular dichroism (CD) spectra with other reported compounds. The possible reversal effects of all compounds were assayed in the resistant cancer cell lines. Stachybotrysin B (8) can reverse multidrug resistance (MDR) in ABCB1-overexpression cells (KBv200, Hela/VCR) at the non-cytotoxic concentration. Doxorubicin accumulation assay and molecular-docking analysis reveal that the mechanism of its reversal MDR effect may be related to the increase in the intracellular concentration of substrate anticancer drugs.


Asunto(s)
Stachybotrys , Humanos , Bioensayo , Dicroismo Circular , Células HeLa , Resistencia a Múltiples Medicamentos
18.
Int J Mol Sci ; 25(7)2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38612426

RESUMEN

This paper describes the effects of murine norovirus (MNV) infection on oxidative stress and histopathological changes in mice. This study uses histopathological assays, enzymatic and non-enzymatic antioxidant markers, and total oxidative status and capacity (TOS, TAC). The results suggest that MNV infection can lead to significant changes with respect to the above-mentioned parameters in various organs. Specifically, reduced superoxide dismutase (SOD), Mn superoxide dismutase (MnSOD), catalase (CAT), and glutathione reductase (GR) activities were observed in liver tissues, while higher MnSOD activity was observed in kidney tissues of MNV-infected mice when compared to the control. GR activity was lower in all tissues of MNV-infected mice tested, with the exception of lung tissue. This study also showed that norovirus infection led to increased TOS levels in the brain and liver and TAC levels in the brain, while TOS levels were significantly reduced in the kidneys. These changes may be due to the production of reactive oxygen species (ROS) caused by the viral infection. ROS can damage cells and contribute to oxidative stress. These studies help us to understand the pathogenesis of MNV infection and its potential effects on oxidative stress and histopathological changes in mice, and pave the way for further studies of the long-term effects of MNV infection.


Asunto(s)
Norovirus , Estrés Oxidativo , Animales , Ratones , Especies Reactivas de Oxígeno , Antioxidantes , Bioensayo
19.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38612669

RESUMEN

The multidrug and toxin efflux (MATE) family participates in numerous biological processes and plays important roles in abiotic stress responses. However, information about the MATE family genes in Torreya grandis remains unclear. In this study, our genome-wide investigation identified ninety MATE genes in Torreya grandis, which were divided into five evolutionary clades. TgMATE family members are located on eleven chromosomes, and a total of thirty TgMATEs exist in tandem duplication. The promoter analysis showed that most TgMATEs contain the cis-regulatory elements associated with stress and hormonal responses. In addition, we discovered that most TgMATE genes responded to abiotic stresses (aluminum, drought, high temperatures, and low temperatures). Weighted correlation network analysis showed that 147 candidate transcription factor genes regulated the expression of 14 TgMATE genes, and it was verified through a double-luciferase assay. Overall, our findings offer valuable information for the characterization of the TgMATE gene mechanism in responding to abiotic stress and exhibit promising prospects for the stress tolerance breeding of Torreya grandis.


Asunto(s)
Taxaceae , Toxinas Biológicas , Fitomejoramiento , Aluminio , Bioensayo , Estrés Fisiológico/genética
20.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38612672

RESUMEN

Acinetobacter baumannii is a major cause of nosocomial infections, and its highly adaptive nature and broad range of antibiotic resistance enable it to persist in hospital environments. A. baumannii often employs two-component systems (TCSs) to regulate adaptive responses and virulence-related traits. This study describes a previously uncharacterized TCS in the A. baumannii ATCC19606 strain, consisting of a transcriptional sensor, DJ41_1407, and its regulator, DJ41_1408, located adjacent to GacA of the GacSA TCS. Markerless mutagenesis was performed to construct DJ41_1407 and DJ41_1408 single and double mutants. DJ41_1408 was found to upregulate 49 genes and downregulate 43 genes, most of which were associated with carbon metabolism and other metabolic pathways, such as benzoate degradation. MEME analysis revealed a putative binding box for DJ41_1408, 5'TGTAAATRATTAYCAWTWAT3'. Colony size, motility, biofilm-forming ability, virulence, and antibiotic resistance of DJ41_1407 and DJ41_1408 single and double mutant strains were assessed against wild type. DJ41_1407 was found to enhance motility, while DJ41_1408 was found to upregulate biofilm-forming ability, and may also modulate antibiotic response. Both DJ41_1407 and DJ41_1408 suppressed virulence, based on results from a G. mellonella infection assay. These results showcase a novel A. baumannii TCS involved in metabolism, with effects on motility, biofilm-forming ability, virulence, and antibiotic response.


Asunto(s)
Acinetobacter baumannii , Acinetobacter baumannii/genética , Virulencia/genética , Antibacterianos/farmacología , Biopelículas , Bioensayo
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