Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
Environ Int ; 191: 108968, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39213918

RESUMEN

Global sensitivity analysis combined with quantitative high-throughput screening (GSA-qHTS) uses random starting points of the trajectories in mixture design, which may lead to potential contingency and a lack of representativeness. Moreover, a scenario in which all factor levels were at stimulatory effects was not considered, thereby hindering a comprehensive understanding of GSA-qHTS. Accordingly, this study innovatively introduced an optimised experimental design, uniform design (UD), to generate non-random and representative sample points with smaller uniformity deviation as starting points of multiple trajectories. By combining UD with the previously optimised one-factor-at-a-time (OAT) method, a novel mixture design method was developed (UD-OAT). The single toxicity tests showed that three pyridinium and five imidazolium ionic liquids (ILs) exerted stimulatory effects on Vibrio qinghaiensis sp.-Q67; thus, four stimulatory effective concentrations of each IL were selected as factor levels. The UD-OAT generated 108 mixture samples with equal frequency and without repetition. High-throughput microplate toxicity analysis revealed that all 108 mixtures exhibited inhibitory effects. Among these, type B mixtures exhibited increasing toxicities that subsequently decreased, unlike type C mixtures, which consistently increased over time. GSA successfully identified three of the eight ILs as important factors influencing the toxicities of the mixtures. When individual ILs produced stimulatory effects, mixtures containing two to three ILs exhibited either stimulatory effects or none. In contrast, mixtures containing five to eight ILs exhibited inhibitory effects, while those containing four ILs showed a transition from stimulatory to inhibitory effects. This study provides a novel mixture design method for studying mixture toxicity and fills the application gap of GSA-qHTS. The phenomenon of individuals being beneficial while mixtures can be harmful challenges traditional mixture risk assessments.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Líquidos Iónicos , Pruebas de Toxicidad , Vibrio , Líquidos Iónicos/toxicidad , Líquidos Iónicos/química , Pruebas de Toxicidad/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Vibrio/efectos de los fármacos , Proyectos de Investigación , Imidazoles/toxicidad
2.
Brain Sci ; 14(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39061419

RESUMEN

Mitral cells (MCs) in the main olfactory bulb relay odor information to higher-order olfactory centers by encoding the information in the form of action potentials. The firing patterns of these cells are influenced by both their intrinsic properties and their synaptic connections within the neural network. However, reports on MC firing patterns have been inconsistent, and the mechanisms underlying these patterns remain unclear. Using whole-cell patch-clamp recordings in mouse brain slices, we discovered that MCs exhibit two types of integrative behavior: regular/rhythmic firing and bursts of action potentials. These firing patterns could be transformed both spontaneously and chemically. MCs with regular firing maintained their pattern even in the presence of blockers of fast synaptic transmission, indicating this was an intrinsic property. However, regular firing could be transformed into bursting by applying GABAA receptor antagonists to block inhibitory synaptic transmission. Burst firing could be reverted to regular firing by blocking ionotropic glutamate receptors, rather than applying a GABAA receptor agonist, indicating that ionotropic glutamatergic transmission mediated this transformation. Further experiments on long-lasting currents (LLCs), which generated burst firing, also supported this mechanism. In addition, cytoplasmic Ca2+ in MCs was involved in the transformation of firing patterns mediated by glutamatergic transmission. Metabotropic glutamate receptors also played a role in LLCs in MCs. These pieces of evidence indicate that odor information can be encoded on a mitral cell (MC) platform, where it can be relayed to higher-order olfactory centers through intrinsic and dendrodendritic mechanisms in MCs.

3.
Viruses ; 16(4)2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38675901

RESUMEN

As SARS-CoV-2 continues to evolve and COVID-19 cases rapidly increase among children and adults, there is an urgent need for a safe and effective vaccine that can elicit systemic and mucosal humoral immunity to limit the emergence of new variants. Using the Chinese Hu191 measles virus (MeV-hu191) vaccine strain as a backbone, we developed MeV chimeras stably expressing the prefusion forms of either membrane-anchored, full-length spike (rMeV-preFS), or its soluble secreted spike trimers with the help of the SP-D trimerization tag (rMeV-S+SPD) of SARS-CoV-2 Omicron BA.2. The two vaccine candidates were administrated in golden Syrian hamsters through the intranasal or subcutaneous routes to determine the optimal immunization route for challenge. The intranasal delivery of rMeV-S+SPD induced a more robust mucosal IgA antibody response than the subcutaneous route. The mucosal IgA antibody induced by rMeV-preFS through the intranasal routine was slightly higher than the subcutaneous route, but there was no significant difference. The rMeV-preFS vaccine stimulated higher mucosal IgA than the rMeV-S+SPD vaccine through intranasal or subcutaneous administration. In hamsters, intranasal administration of the rMeV-preFS vaccine elicited high levels of NAbs, protecting against the SARS-CoV-2 Omicron BA.2 variant challenge by reducing virus loads and diminishing pathological changes in vaccinated animals. Encouragingly, sera collected from the rMeV-preFS group consistently showed robust and significantly high neutralizing titers against the latest variant XBB.1.16. These data suggest that rMeV-preFS is a highly promising COVID-19 candidate vaccine that has great potential to be developed into bivalent vaccines (MeV/SARS-CoV-2).


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Inmunidad Humoral , Inmunidad Mucosa , Inmunoglobulina A , Virus del Sarampión , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Animales , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Virus del Sarampión/inmunología , Virus del Sarampión/genética , Cricetinae , Inmunoglobulina A/sangre , Humanos , Administración Intranasal , Mesocricetus , Femenino
4.
bioRxiv ; 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38464246

RESUMEN

EAG1 depolarization-activated potassium selective channels are important targets for treatment of cancer and neurological disorders. EAG1 channels are formed by a tetrameric subunit assembly with each subunit containing an N-terminal Per-Arnt-Sim (PAS) domain and C-terminal cyclic nucleotide-binding homology (CNBH) domain. The PAS and CNBH domains from adjacent subunits interact and form an intracellular tetrameric ring that regulates the EAG1 channel gating, including the movement of the voltage sensor domain (VSD) from closed to open states. Small molecule ligands can inhibit EAG1 channels by binding to their PAS domains. However, the allosteric pathways of this inhibition are not known. Here we show that chlorpromazine, a PAS domain small molecule binder, alters interactions between the PAS and CNBH domains and decreases the coupling between the intracellular tetrameric ring and the pore of the channel, while having little effect on the coupling between the PAS and VSD domains. In addition, chlorpromazine binding to the PAS domain did not alter Cole-Moore shift characteristic of EAG1 channels, further indicating that chlorpromazine has no effect on VSD movement from the deep closed to opened states. Our study provides a framework for understanding global pathways of EAG1 channel regulation by small molecule PAS domain binders.

5.
J Biol Chem ; 299(12): 105391, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37898402

RESUMEN

Ether-a-go-go (EAG) channels are key regulators of neuronal excitability and tumorigenesis. EAG channels contain an N-terminal Per-Arnt-Sim (PAS) domain that can regulate currents from EAG channels by binding small molecules. The molecular mechanism of this regulation is not clear. Using surface plasmon resonance and electrophysiology we show that a small molecule ligand imipramine can bind to the PAS domain of EAG1 channels and inhibit EAG1 currents via this binding. We further used a combination of molecular dynamics (MD) simulations, electrophysiology, and mutagenesis to investigate the molecular mechanism of EAG1 current inhibition by imipramine binding to the PAS domain. We found that Tyr71, located at the entrance to the PAS domain cavity, serves as a "gatekeeper" limiting access of imipramine to the cavity. MD simulations indicate that the hydrophobic electrostatic profile of the cavity facilitates imipramine binding and in silico mutations of hydrophobic cavity-lining residues to negatively charged glutamates decreased imipramine binding. Probing the PAS domain cavity-lining residues with site-directed mutagenesis, guided by MD simulations, identified D39 and R84 as residues essential for the EAG1 channel inhibition by imipramine binding to the PAS domain. Taken together, our study identified specific residues in the PAS domain that could increase or decrease EAG1 current inhibition by imipramine binding to the PAS domain. These findings should further the understanding of molecular mechanisms of EAG1 channel regulation by ligands and facilitate the development of therapeutic agents targeting these channels.


Asunto(s)
Canales de Potasio Éter-A-Go-Go , Imipramina , Fenómenos Electrofisiológicos , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Canales de Potasio Éter-A-Go-Go/química , Canales de Potasio Éter-A-Go-Go/genética , Imipramina/química , Imipramina/farmacología , Unión Proteica , Animales , Dominios Proteicos , Ratones , Xenopus
6.
Viruses ; 15(9)2023 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-37766275

RESUMEN

Coxsackievirus A5 (CV-A5) is a re-emerging enterovirus that causes hand, foot, and mouth disease in children under five years of age. CV-A5-M14-611 is a mouse-adapted strain that can infect orally and lead to the death of 14-day-old mice. Here, recombinants based on CV-A5-M14-611 were constructed carrying three reporter genes in different lengths. Smaller fluorescent marker proteins, light, oxygen, voltage sensing (iLOV), and nano luciferase (Nluc) were proven to be able to express efficiently in vitro. However, the recombinant with the largest insertion of the red fluorescence protein gene (DsRed) was not rescued. The construction strategy of reporter viruses was to insert the foreign genes between the C-terminus of VP1 and the N-terminus of 2A genes and to add a 2A protease cleavage domain at both ends of the insertions. The iLOV-tagged or Nluc-tagged recombinants, CV-A5-iLOV or CV-A5-Nluc, exhibited a high capacity for viral replication, genetic stability in cells and pathogenicity in mice. They were used to establish a rapid, inexpensive and convenient neutralizing antibody assay and greatly facilitated virus neutralizing antibody titration. Living imaging was performed on mice with CV-A5-Nluc, which exhibited specific bioluminescence in virus-disseminated organs, while fluorescence induced by CV-A5-iLOV was weakly detected. The reporter-gene-tagged CV-A5 can be used to study the infection and mechanisms of CV-A5 pathogenicity in a mouse model. They can also be used to establish rapid and sensitive assays for detecting neutralizing antibodies.


Asunto(s)
Infecciones por Coxsackievirus , Enterovirus , Niño , Ratones , Animales , Humanos , Preescolar , Enterovirus/genética , Luciferasas , Genes Reporteros , Fluorescencia , Anticuerpos Neutralizantes
7.
Toxics ; 11(7)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37505529

RESUMEN

For persistent organic pollutants, a concern of environmental supervision, predicted no-effect concentrations (PNECs) are often used in ecological risk assessment, which is commonly derived from the hazardous concentration of 5% (HC5) of the species sensitivity distribution (SSD). To address the problem of a lack of toxicity data, the objectives of this study are to propose and apply two improvement ideas for SSD application, taking polycyclic aromatic hydrocarbons (PAHs) as an example: whether the chronic PNEC can be derived from the acute SSD curve; whether the PNEC may be calculated by HC10 to avoid solely statistical extrapolation. In this study, the acute SSD curves for eight PAHs and the chronic SSD curves for three PAHs were constructed. The quantity relationship of HC5s between the acute and chronic SSD curves was explored, and the value of the assessment factor when using HC10 to calculate PNEC was derived. The results showed that, for PAHs, the chronic PNEC can be estimated by multiplying the acute PNEC by 0.1, and the value of the assessment factor corresponding to HC10 is 10. For acenaphthene, anthracene, benzo[a]pyrene, fluoranthene, fluorene, naphthalene, phenanthrene, and pyrene, the chronic PNECs based on the acute HC10s were 0.8120, 0.008925, 0.005202, 0.07602, 2.328, 12.75, 0.5731, and 0.05360 µg/L, respectively.

8.
Sci Total Environ ; 893: 164918, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37327899

RESUMEN

With the widespread use of pesticides, the coexistence of multiple low-residue pesticides in environmental media has increased significantly, and the "cocktail" effect caused by this phenomenon has garnered increasing attention. However, owing to the scarcity of information regarding the modes of action (MOAs) of chemicals, the application of concentration addition (CA) models for evaluating and predicting the toxicity of mixture with similar MOAs is limited. Additionally, the joint toxicity laws of complex mixture systems to different toxicity endpoints in organisms remain unclear, and effective methods to test the mixture toxicity on lifespan and reproductive inhibition are lacking. Therefore, in this study, the similarity of pesticide MOAs was characterized using molecular electronegativity-distance vector (MEDV-13) descriptors based on eight pesticides (aldicarb, methomyl, imidacloprid, thiamethoxam, dichlorvos, dimethoate, methamidophos and triazophos). Additionally, the methods of lifespan and reproduction inhibition microplate toxicity analysis of elegans (EL-MTA and ER-MTA) were established to test the lifespan and reproduction inhibition toxicity of Caenorhabditis elegans. Finally, a unified scale synergistic-antagonistic heatmap (SAHscale) method was proposed to explore the combined toxicity of the mixtures on the lifespan, reproduction, and mortality of nematodes. The results showed that the MEDV-13 descriptors could effectively characterize the similarity in MOAs. The lifespan and reproductive ability of Caenorhabditis elegans were significantly inhibited when the pesticide exposure concentration was one order of magnitude lower than the lethal dose. The sensitivity of lifespan and reproductive endpoints to mixtures was dependent on the concentration ratio. The same rays in the mixture had consistent toxicity interactions on the lifespan and reproductive endpoints of Caenorhabditis elegans. In conclusion, we demonstrated the feasibility of MEDV-13 in characterizing the similarity of MOAs, and provided a theoretical basis for exploring the mechanism of chemical mixtures by studying their apparent toxicity of mixtures on nematode lifespan and reproduction endpoints.


Asunto(s)
Nematodos , Plaguicidas , Animales , Caenorhabditis elegans , Plaguicidas/toxicidad , Relación Dosis-Respuesta a Droga , Dimetoato
9.
J Mater Chem B ; 11(28): 6491-6515, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37337868

RESUMEN

Ionic liquids (ILs) are composed of asymmetric cationic and anionic moieties and are used as green solvents. Their non-toxic nature, favorable biocompatibility and adjustable structure facilitate wide biomedical applications. ILs promote the generation of various nanohybrids that exhibit multiple functions and novel/improved properties with respect to their precursors. Generally, nanostructures have a large specific surface area and abundant functional groups which enable loading and incorporation of ILs through physical interactions or chemical bonding. According to their main skeleton structures, IL-based nanohybrids may be divided into five categories, i.e., poly(ionic liquid)s (PILs), IL-inorganic nanohybrids, IL-metal organic framework nanohybrids (IL-MOF nanohybrids), ILs/carbon materials and ionic materials. These IL-based nanohybrids exhibit various specific features, including thermal responsive behavior, metal chelating, photothermal conversion and antibacterial capabilities. Taking advantage of these characteristics, IL-based nanohybrids may overcome the shortcomings of conventional medicines/drugs and exhibit promising prospects in biomedicine to facilitate controlled drug release, bactericidal treatment and thermotherapy. The present review presents the state-of-the-art progress made in the studies of IL-based nanohybrids in terms of their classifications, structure characteristics, versatile functionalities and biomedical and pharmaceutical applications. The challenges and future perspectives in the developments and applications of IL-based nanohybrids in biomedicine are discussed.


Asunto(s)
Líquidos Iónicos , Estructuras Metalorgánicas , Líquidos Iónicos/química , Solventes/química , Iones , Antibacterianos/farmacología
10.
Sheng Li Xue Bao ; 75(3): 351-359, 2023 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-37340644

RESUMEN

To explore the changes of cold sensitivity after exposure to acute hypoxia and its mechanisms, Sprague-Dawley rats were divided into normoxia control group (21% O2, 25 °C), 10% O2 hypoxia group (10% O2, 25 °C), 7% O2 hypoxia group (7% O2, 25 °C), normoxia cold group (21% O2, 10 °C) and hypoxia cold group (7% O2, 10 °C). Cold foot withdrawal latency and preference temperature of each group were measured, skin temperatures were estimated using an infrared thermographic imaging camera, body core temperature was recorded by wireless telemetry system, immunohistochemical staining was used to detect the expression of c-Fos in the lateral parabrachial nucleus (LPB). The results showed that acute hypoxia significantly prolonged the latency of cold foot withdrawal and significantly enhanced the intensity of cold stimulation for foot withdrawal, and the rats under hypoxia preferred cold temperature. Cold exposure (10 °C) for 1 h significantly enhanced the expression of c-Fos in LPB of rats in normoxia, while hypoxia inhibited cold-induced c-Fos expression. Acute hypoxia significantly increased the skin temperature of feet and tails, decreased the skin temperature of interscapular region, and decreased the body core temperature of rats. These results indicate that acute hypoxia can significantly blunt cold sensitivity through the inhibition of LPB, suggesting actively keeping warm measures should be taken at the early stage after ascent to high altitude to prevent the upper respiratory infection and acute mountain sickness.


Asunto(s)
Núcleos Parabraquiales , Ratas , Animales , Ratas Sprague-Dawley , Núcleos Parabraquiales/fisiología , Temperatura , Frío , Hipoxia , Proteínas Proto-Oncogénicas c-fos
11.
Viruses ; 15(4)2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37113008

RESUMEN

Outbreaks of hand, foot and mouth disease (HFMD) have occurred frequently in the Asian-Pacific region over the last two decades, caused mainly by the serotypes in Enterovirus A species. High-quality monoclonal antibodies (mAbs) are needed to improve the accuracy and efficiency of the diagnosis of enteroviruses associated HFMD. In this study, a mAb 1A11 was generated using full particles of CV-A5 as an immunogen. In indirect immunofluorescence and Western blotting assays, 1A11 bound to the viral proteins of CV-A2, CV-A4, CV-A5, CV-A6, CV-A10, CV-A16, and EV-A71 of the Enterovirus A and targeted VP3. It has no cross-reactivity to strains of Enterovirus B and C. By mapping with over-lapped and truncated peptides, a minimal and linear epitope 23PILPGF28 was identified, located at the N-terminus of the VP3. A BLAST sequence search of the epitope in the NCBI genus Enterovirus (taxid: 12059) protein database indicates that the epitope sequence is highly conserved among the Enterovirus A species, but not among the other enterovirus species, first reported by us. By mutagenesis analysis, critical residues for 1A11 binding were identified for most serotypes of Enterovirus A. It may be useful for the development of a cost-effective and pan-Enterovirus A antigen detection for surveillance, early diagnosis and differentiation of infections caused by the Enterovirus A species.


Asunto(s)
Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , Humanos , Enterovirus/genética , Epítopos , Infecciones por Enterovirus/diagnóstico , Infecciones por Enterovirus/epidemiología , Enterovirus Humano A/genética , Antígenos Virales , China/epidemiología
12.
Environ Int ; 175: 107940, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37119652

RESUMEN

The research framework combining global sensitivity analysis (GSA) with quantitative high-throughput screening (qHTS), called GSA-qHTS, provides a potentially feasible way to screen for important factors that induce toxicities of complex mixtures. Despite its value, the mixture samples designed using the GSA-qHTS technique still have a shortage of unequal factor levels, which leads to an asymmetry in the importance of elementary effects (EEs). In this study, we developed a novel method for mixture design that enables equal frequency sampling of factor levels (called EFSFL) by optimizing both the trajectory number and the design and expansion of the starting points for the trajectory. The EFSFL has been successfully employed to design 168 mixtures of 13 factors (12 chemicals and time) that each have three levels. By means of high-throughput microplate toxicity analysis, the toxicity change rules of the mixtures are revealed. Based on EE analysis, the important factors affecting the toxicities of the mixtures are screened. It was found that erythromycin is the dominant factor and time is an important non-chemical factor in mixture toxicities. The mixtures can be classified into types A, B, and C mixtures according to their toxicities at 12 h, and all the types B and C mixtures contain erythromycin at the maximum concentration. The toxicities of the type B mixtures increase firstly over time (0.25 âˆ¼ 9 h) and then decrease (12 h), while those of the type C mixtures consistently increase over time. Some type A mixtures produce stimulation that increases with time. With the present new approach to mixture design, the frequency of factor levels in mixture samples is equal. Consequently, the accuracy of screening important factors is improved based on the EE method, providing a new method for the study of mixture toxicity.


Asunto(s)
Vibrio , Eritromicina/farmacología , Mezclas Complejas , Ensayos Analíticos de Alto Rendimiento
13.
Chemosphere ; 326: 138341, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36925008

RESUMEN

The environmental and ecological consequences of nanoplastics (NPs) draw increasing research interests and social concerns. However, the in situ and real-time detection of NPs from living organisms and transferring media remains as a major technical obstacle for scientific investigation. Herein we report a novel time-gated imaging (TGI) strategy capable of real-time visualizing the intake of NPs by an individual living organism, which is based on the polystyrene NPs labelled with lanthanide up-conversion luminescence. The limit of detection (LOD) of the TGI apparatus was 600 pg (SNR = 3) in a field of view of 2.4 × 3.8 mm. Taking Daphnia magna as the aquatic model, we investigated the dynamics of uptake and accumulation of NPs (500 µg/L) for 24 h, and the subsequent excretion process (in clean medium) for 48 h, and quantitively analyzed the distribution and the overall mass of NPs deposited in D. magna. The uptake of NPs via filter-feeding occurred in a few minutes, whereas a longer accumulation was found, in a timescale of several hours. And similar behaviors (bi-phase elimination) were also seen in the excretion, indicating the migration of NPs into the circulatory system. The average mass of NPs accumulated in an individual D. magna was ∼12 ng after 24 h exposure, indicating that D. magna as a filter feeder tends to retain NPs. The observed NPs accumulation in D. magna exemplifies the potential risk of aquatic ecosystem on exposure to NP contamination.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Animales , Daphnia , Poliestirenos , Ecosistema , Luminiscencia , Imagen Óptica , Contaminantes Químicos del Agua/toxicidad
14.
Front Mol Biosci ; 10: 1106832, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36793784

RESUMEN

The purple non-sulfur bacterium Rhodobacter sphaeroides was selected as a biological model to investigate its response to the toxicity of 1-alkyl-3-methylimidazolium bromide ([Cnmim]Br), a type of ionic liquid (IL), with different alkyl chain lengths (n describes the number of carbon atoms in the alkyl chain). The inhibition of bacterial growth by [Cnmim]Br was positively correlated with n. Morphological characterization revealed that [Cnmim]Br caused cell membrane perforation. The signal amplitude of the electrochromic absorption band shift of endogenous carotenoids showed a negatively linear correlation with n, and the amplitude of the blue-shift of the B850 band in light-harvesting complex 2 showed a positively linear correlation with n. Furthermore, an increase in blocked ATP synthesis and increase in antioxidant enzyme activity were observed in chromatophores treated with ILs containing longer alkyl chains. In summary, the purple bacterium can be developed as a model to monitor ecotoxicity and examine the mechanism of IL toxicity.

15.
Virus Res ; 328: 199074, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36805409

RESUMEN

Hand, foot and mouth disease (HFMD) is caused by a variety of serotypes in species A of the Enterovirus genus, including recently re-emerged Coxsackievirus A2 (CV-A2), CV-A4 and CV-A5. For development of diagnostic reagents, for surveillance, and the development of multivalent vaccines against HFMD, the antigenicity of HFMD-associated enteroviruses warrants investigation. The purified virions of CV-A4 were inoculated into Balb/c mice and hybridomas were obtained secreting monoclonal antibodies (mAbs) directed against CV-A4 and cross-reacting with other closely related species A enteroviruses. The mAbs were characterized by ELISA, Western blotting and in vitro neutralizing assays. The majority of mAbs was non-neutralizing, with only 2% of the mAbs neutralizing CV-A4 specifically. Most of mAbs bound to linear VP1 epitopes of CV-A4. Interestingly, four types of mAbs were obtained which bound specifically to CV-A4 or were broadly to CV-A4/-A2, CV-A4/-A5 and CV-A4/-A2/-A5, respectively. Mapping with overlapping or single-amino-acid mutant peptides revealed that the four types of mAbs all bound to the first 15 amino acids at the N-terminus of the VP1. This region of picornaviruses is functionally important as it is involved in uncoating and releasing of viral RNA into the cytosol. The binding footprints of four type mAbs are composed of conserved and variable residues and are different from each other. The newly discovered broadly cross-reactive mAbs reflect the high homology of CV-A4/ CV-A2/CV-A5. The results also demonstrate that it is possible and beneficial to develop the diagnostic reagents to detect rapidly the main pathogens of enteroviruses associated with HFMD cause by CV-A4/CV-A2/CV-A5.


Asunto(s)
Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , Animales , Ratones , Anticuerpos Monoclonales , Epítopos , Enterovirus/genética , Antígenos Virales , China/epidemiología , Enterovirus Humano A/genética
16.
Anal Chem ; 95(4): 2523-2531, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36657481

RESUMEN

Exosomes are recognized as noteworthy biomarkers playing unprecedented roles in intercellular communication and disease diagnosis and treatment. It is a prerequisite to obtain high-purity exosomes for the comprehension of exosome biochemistry and further illustration of their functionality/mechanisms. However, the isolation of nanoscale exosomes from endogenous proteins is particularly challenging for small-volume biological samples. Herein, a Dean-flow-coupled elasto-inertial microfluidic chip (DEIC) was developed. It consists of a spiral microchannel with dimensional confined concave structures and facilitates elasto-inertial separation of exosomes with lower protein contaminants from cell culture medium and human serum. The presence of 0.15% (w/v) poly-(oxyethylene) controls the elastic lift force acting on suspended nanoscale particles and makes it feasible for field-free purification of integrity exosomes with a 70.6% recovery and a 91.4% removal rate for proteins. As a proof of concept, the technique demonstrated the individual-vesicle-level biomarker (EpCAM and PD-L1) profiling in combination with simultaneous aptamer-mediated analysis to disclose the sensibility for immune response. Overall, DEIC enables the collection of high-purity exosomes and exhibits potential in integration with downstream analyses of exosomes.


Asunto(s)
Exosomas , Humanos , Exosomas/química , Microfluídica/métodos , Técnicas de Cultivo de Célula , Proteínas/análisis
17.
Emerg Microbes Infect ; 12(1): e2147022, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36373411

RESUMEN

Coxsackievirus A10 (CV-A10) has become one of the major pathogens of hand, foot and mouth disease (HFMD), and studies on the vaccine and animal model of CV-A10 are still far from complete. Our study used a mouse-adapted CV-A10 strain, which was lethal for 14-day-old mice, to develop an infected mouse model. Then this model was employed to establish an actively immunized-challenged mouse model to evaluate the efficacy of a formaldehyde-inactivated CV-A10 vaccine, which was prepared from a Vero cell-adapted strain. CV-A10 vaccine at a dose of 0.5 or 2.0 µg was inoculated intraperitoneally in neonatal Kunming mice on the third and ninth day. Then the mice were challenged on day 14. The survival rate of mice immunized with 0.5 or 2.0 µg vaccine were 90% and 100%, respectively, while all Alum-inoculated mice died. Compared to those in the two vaccinated groups, the Alum-inoculated mice showed severe pathological damage, strong viral protein expression and high viral loads. The antisera from vaccinated mice showed high level of neutralizing antibodies against CV-A10. Meanwhile, three potential T cell epitopes located at the carboxyl-terminal regions of the VP1 and VP3 were identified and exhibited CV-A10 serotype-specific. The humoral and cellular immunogenicity analysis showed that immunization with two doses of the vaccine elicited CV-A10 specific neutralizing antibody and T cell response in BALB/c mice. Collectively, these findings indicated that this actively immunized-challenged mouse model will be invaluable in future studies on CV-A10 pathogenesis and evaluation of vaccine candidates.


Asunto(s)
Enterovirus Humano A , Enfermedad de Boca, Mano y Pie , Vacunas Virales , Ratones , Animales , Enfermedad de Boca, Mano y Pie/prevención & control , Anticuerpos Antivirales , Anticuerpos Neutralizantes , Vacunas de Productos Inactivados , Enterovirus Humano A/genética
18.
Sci Total Environ ; 855: 158981, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36155044

RESUMEN

Some personal care products (PCPs) and their chemical components showed a hormetic effect in the freshwater photobacterium Vibrio qinghaiensis sp. -Q67 (Q67) after long-term exposure. However, how hormesis transfers between chemical components and PCP mixture, and which chemical component plays a major role remain unknown. To this end, according to the seven compounds detected in one skin lotion (SK5) and their concentration ratios, many mixture rays were constructed to simulate the SK5. Of these seven compounds, three presented monotonic concentration-response curves (CRC) to Q67 at 0.25 and 12 h (called a S-shaped compound). The other four compounds showed hormetic CRCs after 12 h and monotonic CRCs at 0.25 h (called a J-shaped compound). Based on their mixture ratios, we designed one ternary mixture ray of all S-shaped compounds, one quaternary mixture ray of all J-shaped compounds, and four quaternary mixture rays of one J-shaped and three S-shaped compounds. It was shown that SK5 could be approximately simulated by the mixture ray of the seven compounds detected in SK5 and only the mixture rays containing at least one hormesis-inducing compound produced hormesis to Q67 at 12 h. Based on the concentration ratios of various compounds and comparison of four hormetic characteristic parameters to those of various mixture rays, it was found that the compound betaine (BET) is a key compound affecting the hormesis of mixtures. Additionally, we studied the hormesis mechanism of BET on Q67 via quorum sensing (QS). This preliminarily indicated that the autoinducer-2 triggered the QS pathway. This study elucidated the transfer pattern of hormesis into mixtures, which would be an efficient method to identifying the potential components that affect hormesis transfer in mixtures. We expect that this study will provide new insights into hormesis and its mixtures.


Asunto(s)
Cosméticos , Hormesis
19.
Environ Pollut ; 315: 120378, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36220575

RESUMEN

The environmental pollution caused by toxic chemicals such as pesticides has become a global problem. The mixture of dichlorvos (DIC), dimethoate (DIM), aldicarb (ALD) poses potential risks to the environment and human health. To fully explore the interaction of complex mixtures on Caenorhabditis elegans behavioral toxicity endpoint. This study created a synergistic-antagonistic heatmap (SAHmap) based on the combination index to systematically describe the toxicological interaction prospect of the mixture system. It was shown that the three pesticides and their binary as well as ternary mixture rays have significant concentration-response relationship on three behavioral endpoints of nematodes, From the perspective of synergistic-antagonistic heatmaps, all the mixture rays in the DIC-DIM mixture system showed strong synergism on the three behavioral and lethal endpoints. In the ternary mixture system, the five mixture rays showed different interaction between the behavioral endpoint and the lethal endpoint, and showed slight synergism to two behavioral endpoints as a whole. The emergence of synergism should arouse our attention to these hazardous chemicals. In addition, the use of SAHmap and the significant linear correlation among three behavioral endpoints further improved the efficiency of the study on the behavioral toxicity of pesticide mixtures to Caenorhabditis elegans.


Asunto(s)
Plaguicidas , Animales , Humanos , Plaguicidas/toxicidad , Caenorhabditis elegans , Diclorvos/toxicidad , Dimetoato/toxicidad
20.
J Gastrointest Oncol ; 13(4): 1805-1817, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36092341

RESUMEN

Background: Although studies have reported that certain sleep characteristics, such as sleep duration and sleep apnea, are linked to the risk of colorectal cancer (CRC), this link remains contentious because of the limited evidence from individual studies. Furthermore, evidence indicated that shift work involving circadian disruption as a probable human carcinogen. This systematic review and meta-analysis aimed to examine the associations between sleep duration, sleep apnea, and shift work with the risk of colorectal neoplasms, including CRC and colorectal adenoma (CRA). Methods: We conducted a comprehensive literature search in PubMed, Embase, and Web of Science databases. The inclusion criteria were determined using PICOS principles. Observational studies reporting associations of sleep duration, sleep apnea, or shift work with risk of CRC or CRA were included. We assessed the risk of bias on the basis of the Newcastle-Ottawa Scale. Results: A total of 18 observational studies were included. Of these studies, nine studies reported the effect of sleep duration on risk of colorectal neoplasms, five reported the effect of sleep apnea, and six reported the effect of shift work. The relative risk (RR) for colorectal neoplasms was 1.06 [95% confidence interval (CI): 0.94, 1.20] in the short sleep duration group compared with the moderate sleep duration group. Long sleep duration was associated with an increased risk of colorectal neoplasms (RR: 1.33, 95% CI: 1.07, 1.65). The pooled results showed that sleep apnea was associated with an increased risk of colorectal neoplasms (RR: 1.75, 95% CI: 1.56, 1.97). Furthermore, results showed that the association between shift work and the risk of colorectal neoplasms was not significant (RR: 1.06, 95% CI: 0.95, 1.17). No publication bias was observed in all the analyses (all P>0.05). The sensitivity analysis showed that no individual study substantially influenced the pooled RRs for colorectal neoplasms and CRC. Conclusions: Our findings suggest the significant positive association of long sleep duration and sleep apnea with risk of colorectal neoplasms and CRC. Given that sleep characteristics may be a potentially modifiable risk factor for colorectal neoplasms, further understanding of its role in carcinogenesis will provide valuable insight for cancer prevention.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA