Search Results (7,384)

Acute hepatopancreatic necrosis disease (AHPND) is one of the most important diseases in the global shrimp industry. The emergence of mutant AHPND-associated V. parahaemolyticus (Vp_AHPND) strains has raised concerns regarding potential misdiagnosis and unforeseen pathogenicity. In this study, we report the first emergence of a type II (pirA⁻, pirB⁺) natural mutant, Vp_AHPND (strain 20-082A3), isolated from cultured Penaeus vannamei in Korea. Phenotypic and genetic analyses revealed a close relationship between the mutant strain 20-082A3 and the virulent Korean Vp_AHPND strain 19-021-D1, which caused an outbreak in 2019. Detailed sequence analysis of AHPND-associated plasmids showed that plasmid pVp_20-082A3B in strain 20-082A3 was almost identical (>99.9%) to that of strain 19-021-D1. Moreover, strains 20-082A3 and 19-021-D1 exhibited the same multilocus sequence type (ST 413) and serotype (O1:Un-typeable K-serogroup), suggesting that the mutant strain is closely related to and may have originated from the virulent strain 19-021-D1. Similar to previous reports on the natural mutant Vp_AHPND, strain 20-082A3 did not induce AHPND-related symptoms or cause mortality in the shrimp bioassay. The emergence of a mutant strain which is almost identical to the virulent Vp_AHPND highlights the need for surveillance of the pathogen prevalent in Korea. Further investigations to elucidate the potential relationship between ST 413 and recent Korean Vp_AHPND isolates are needed. Full article

Chrysanthemum morifolium cv. Fubaiju (CMF) is regarded as one of the three most renowned varieties of white Chrysanthemum in China, and different extraction methods have significant effects on its composition and activities. Therefore, six extractions were used in this study to assess the effects on extracts. The basic chemical composition showed that hot water extract (Hw) had the highest total phenolic content, alkali water immersion-assisted hot water extract (Al) had the highest content of protein, and enzyme-assisted hot water extract (Enz) had the highest content of carbohydrate. The UPLC-Q-Exactive-MS results evinced the presence of 19 small-molecule compounds, including chlorogenic acid, caffeic acid, tuberonic acid glucoside, luteolin-7-O-rutinoside, and other substances. In addition, the antioxidant test found that the Hw exhibited the best 1,1-diphenyl-2-picrylhydrazyl (DPPH) (82.05 ± 1.59 mM TE/mg) and 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) (61.91 ± 0.27 mM TE/mg) scavenging ability. The anti-glycation test demonstrated that Enz possessed the most pronounced inhibitory effect on glycation products, including fructosamine and advanced glycation end products (AGEs). Additionally, the Enz also exhibited the most significant inhibitory effect on the protein oxidation product N’-formylkynurenine. The correlation analysis revealed that there was a close relationship between antioxidant properties and glycation resistance of extracts, and tuberonic acid glucoside, 1,3-di-O-caffeoylquinic acid, 1,4-Dicaffeoylquinic acid, quercetin-7-O-β-D-glucopyranoside, and isochlorogenic acid B were key small molecule components that affected activities. In summary, the extracts of CMF can be regarded as an excellent antioxidant and anti-glycosylation agent. Full article

Juglanin (kaempferol 3-O-α-L-arabinofuranoside) is a flavonol glycoside occurring in many plants, including its commercial sources Juglans regia, Polygonum aviculare and Selliguea hastata. Recent extensive studies have explored the potential of using juglanin in various pathological conditions, including cardiovascular disorders, central nervous and skeletal system disorders, metabolic syndrome, hepatic injury, and cancers. The results indicated a wide range of effects, like anti-inflammatory, anti-oxidant, anti-fibrotic, anti-thrombotic, anti-angiogenic, hepatoprotective, hypolipidemic, hypoglycemic, anti-apoptotic (normal cells), and pro-apoptotic (cancer cells). The health-promoting properties of juglanin can be attributed to its influence on many signaling pathways, associated with SIRT1, AMPK, Nrf2, STING, TLR4, MAPKs, NF-κB, AKT, JAK, and their downstream genes. This review primarily summarizes the current knowledge of molecular mechanisms, pharmacokinetics, biocompatibility, and human use safety of juglanin. In addition, the most promising new plant sources and other existing challenges and prospects have also been reviewed and discussed, aiming to provide direction and rationale for the further development and broader pharmaceutical application of juglanin. Full article

Background: The development of the global economy has led to changes in air pollution patterns. The haze phenomenon characterized by high concentrations of particulate matter 2.5 (PM2.5) has changed to complex pollution, and photochemical pollution characterized by ozone (O₃) has become increasingly prominent. Ozone pollution and its impact on human health has become an important topic that needs to be studied urgently. Objective: To investigate the effects of ozone on oxidative stress and inflammation in the nasal mucosa of a rat model. Methods: Thirty-two healthy female Sprague–Dawley rats, eight in each group, were divided into four groups using the randomized numeric table method: normal control group (NC group), normal rats with a low level of ozone inhalation exposure (NEL group, 0.5 ppm), medium ozone inhalation exposure (NEM group, 1 ppm), and high ozone inhalation exposure (NEH group, 2 ppm). The ozone inhalation exposure groups were placed in the ozone inhalation exposure system and exposed to different concentrations of ozone for 2 h each day for 6 weeks. Nasal secretion was measured, and nasal lavage and nasal mucosa were collected. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured by colorimetric assay, and the nasal mucosa was analyzed by Western blot. Western blot (WB) was used to detect the expression of NF-κB p65 nuclear protein in nasal mucosa. The mRNA expression of NF-κB target genes IL-6 and IL-8 and tumor necrosis factor-α (TNF-α) was detected by real-time quantitative PCR (qRT-PCR), and the protein content of pro-inflammatory factors IL-6, IL-8, and TNF-α was detected by ELISA in serum and nasal lavage fluid. The nasal mucosa of rats was stained with hematoxylin-eosin (HE) to observe the pathological changes in the nasal mucosa. The data were analyzed by SPSS 20.0 software. Results: The amount of nasal secretion increased significantly in all groups after ozone exposure compared with that in the NC group. The MDA content of the nasal mucosa was significantly increased in the ozone-exposed group compared with the NC group, and the activity levels of SOD and GSH-Px in the nasal mucosa were lower in the ozone-exposed group than in the NC group. The mRNA expression of IL-6, IL-8, and TNF-α in the nasal mucosa of the ozone-exposed group was elevated, and the protein content of TNF-α, IL-6, and IL-8 in the nasal lavage fluid was elevated, and the content increased with the increase in ozone concentration. The expression of NF-κB p65 intracellular protein in the nasal mucosa of each ozone-exposed group was higher than that of the normal group, and the content increased with the increase in ozone concentration. Conclusions: Ozone inhalation exposure promotes oxidative stress and the release of inflammatory factors TNF-α, IL-6, and IL-8, leading to pathological damage of the nasal mucosa, the degree of which increases with increasing concentration. This pathological process may be related to the activation of the transcription factor NF-κB by ozone in the nasal mucosa of rats, which increases the expression of its target genes. Full article

Monoamine oxidases (MAOs), mitochondrial enzymes that constantly produce hydrogen peroxide (H₂O₂) as a byproduct of their activity, have been recently acknowledged as contributors to oxidative stress in cardiometabolic pathologies. The present study aimed to assess whether MAOs are mediators of valvular oxidative stress and interact in vitro with angiotensin 2 (ANG2) to mimic the activation of the renin–angiotensin system. To this aim, valvular tissue samples were harvested from 30 patients diagnosed with severe primary mitral regurgitation and indication for surgical repair. Their reactive oxygen species (ROS) levels were assessed by means of a ferrous oxidation xylenol orange (FOX) assay, while MAO expression was assessed by immune fluorescence (protein) and qRT-PCR (mRNA). The experiments were performed using native valvular tissue acutely incubated or not with angiotensin 2 (ANG2), MAO inhibitors (MAOI) and the angiotensin receptor blocker, irbesartan (Irb). Correlations between oxidative stress and echocardiographic parameters were also analyzed. Ex vivo incubation with ANG2 increased MAO-A and -B expression and ROS generation. The level of valvular oxidative stress was negatively correlated with the left ventricular ejection fraction. MAOI and Irb reduced valvular H₂O_2. production. In conclusion, both MAO isoforms are expressed in pathological human mitral valves and contribute to local oxidative stress and ventricular functional impairment and can be modulated by the local renin–angiotensin system_. Full article

Chromogranin B (CgB) is involved in the control of the cardiovascular system through the regulation of catecholamine release. Whether CgB can exert direct actions on the endothelium has not yet been clarified. Here, we aimed to investigate the effects of CgB on cell viability, mitochondrial membrane potential, reactive oxygen species (ROS), glutathione (GSH), nitric oxide (NO) release, and the cytosolic calcium concentration ([Ca²⁺]c) in human vascular endothelial cells (HUVECs) cultured under both physiological and peroxidative conditions. In HUVECs, experiments were conducted to establish the proper concentration and timing of CgB stimulation. Thereafter, specific assays were used to evaluate the response of HUVECs cultured in physiologic or oxidative stress conditions to CgB in the presence or absence of β-adrenergic receptor agonists and antagonists and intracellular pathways blockers. Analysis of cell viability, mitochondrial membrane potential, and NO release revealed that CgB was able to cause increased effects in HUVECs cultured in physiological conditions. Additionally, the same analyses performed in HUVECs cultured with H₂O₂, showed protective effects exerted by CgB, which was also able to counteract ROS release and maintain GSH levels. Furthermore, CgB played a dual role on the [Ca²⁺]c depending on the physiological or peroxidative cell culturing conditions. In conclusion, our data provide new information about the direct role of CgB in the physiological regulation of endothelial function and highlight its potential as a protective agent against peroxidative conditions, such as those found in cardiovascular diseases. Full article

Background: Shigellosis is the leading cause of diarrheal deaths worldwide and is particularly dangerous in children under 5 years of age in low- and middle-income countries. Additionally, the rise in antibiotic resistance has highlighted the need for an effective Shigella vaccine. Previously, we have used the Multiple Antigen-Presenting System (MAPS) technology to generate monovalent and quadrivalent Salmonella MAPS vaccines that induce functional antibodies against Salmonella components. Methods: In this work, we detail the development of several monovalent vaccines using O-specific polysaccharides (OSPs) from four dominant serotypes, S. flexneri 2a, 3a, and 6, and S. sonnei. We tested several rhizavidin (rhavi) fusion proteins and selected a Shigella-specific protein IpaB. Quadrivalent MAPS were made with Rhavi-IpaB protein and tested in rabbits for immunogenicity. Results: Individual MAPS vaccines generated robust, functional antibody responses against both IpaB and the individual OSP component. Antibodies to IpaB were effective across Shigella serotypes. We also demonstrate that the OSP antibodies generated are specific to each homologous Shigella O type by performing ELISA and bactericidal assays. We combined the components of each MAPS vaccine to formulate a quadrivalent MAPS vaccine which elicited similar antibody and bactericidal responses compared to their monovalent counterparts. Finally, we show that the quadrivalent MAPS immune sera are functional against several clinical isolates of the serotypes used in the vaccine. Conclusions: This quadrivalent MAPS Shigella vaccine is immunogenicity and warrants further study. Full article

Whole genome sequencing (WGS) has the potential to greatly enhance AMR (Anti-microbial Resistance) surveillance. To characterize the prevalent pathogens and dissemination of various AMR-genes, 73 clinical isolates were obtained from blood and respiratory tract specimens, were characterized phenotypically by VITEK-2 (bioMerieux), and 23 selected isolates were genotypically characterized by WGS (Illumina). AST revealed high levels of resistance with 50.7% XDR, 32.9% MDR, and 16.4% non-MDR phenotype. A total of 11 K. pneumoniae revealed six sequence types, six K-locus, and four O-locus types, with ST437, KL36, and O4 being predominant types, respectively. They carried ESBL genes CTX-M-15 (90.9%), TEM-1D (72.7%), SHV-11 (54.5%), SHV-1, SHV-28, OXA-1, FONA-5, and SFO-1; NDM-5 (72.7%) and 63.6%OXA48-like carbapenamases; 90.9%OMP mutation; dfrA12, sul-1, ermB, mphA, qnrB1, gyrA831, and pmrB1 for other groups. Virulence gene found were Yerisiniabactin (90.9%), aerobactin, RmpADC, and rmpA2. Predominant plasmid replicons were Col(pHAD28), IncFII, IncFIB(pQil), and Col440. A total of seven XDR A. baumannii showed single MLST type(2) and single O-locus type(OCL-1); with multiple AMR-genes: blaADC-73, blaOXA-66, blaOXA-23, blaNDM-1, gyrA, mphE, msrE, and tetB. Both S. aureus tested were found to be ST22, SCCmec IVa(2B), and spa type t309; multiple AMR-genes: blaZ, mecA, dfrC, ermC, and aacA-aphD. Non-MDR Enterococcus faecalis sequenced was ST 946, with multiple virulence genes. This study documents for the first-time prevalent virulence genes and MLST types, along with resistance genes circulating in our center. Full article

This study investigates the impact of language contact on three generations of bilingual Spanish and Uruguayan Portuguese speakers in Rivera City, Uruguay, located on the Uruguayan–Brazilian border. Focusing on the confirmed presence of the Portuguese-like/b/and/v/phonemic distinction, and the lower frequency of the Montevideo Spanish-like approximantized stops in Riverense Spanish (RS), the research examines the production of <v> and <b> in 29 female Rivera Spanish bilinguals belonging to different age groups. More specifically, the aim was to see if the previously observed differential use of language-specific phonological variants could be accounted for by using precise measurements of relative intensity, duration, and voicing coupled with a distributional analysis of realizations derived from auditory coding. At the same time, their production is compared to that of 30 monolingual Montevideo Spanish (MS) speakers, who served as the control group, offering a first description of the production of <v> and <b> within this distinct Rioplatense Spanish variety. Riverense’s higher overall relative intensity, duration, and voicing values support auditory coding results, providing evidence of the expected phonological differences between both Uruguayan Spanish varieties. In particular, an exclusive presence of fricative/v/and less approximantization of/b/in RS speech exposed the influence of Portuguese in Rivera bilinguals and their divergence from MS. In addition, as predicted, the findings reveal a higher presence of Portuguese-like productions of [v] and [b] in older bilinguals when compared to younger generations. This illustrates a continuum from Portuguese-like forms to Spanish-like forms, which is confirmed by both acoustic and distributional analyses. Finally, evidence of the existence of innovative forms resulting from mixing Portuguese and Spanish phonological systems in RS are presented. This study’s findings contribute to sociolinguistics and bilingualism by exposing cross-linguistic influence in a border setting with rigorous analytical methods that offer reliable results and go beyond a basic analysis based on auditory identification. Full article

High-entropy perovskite materials (HEPMs), characterized by their multi-element composition and highly disordered structure, can incorporate multiple rare earth elements at the A-site, producing perovskites with enhanced CO₂ resistance, making them stay high performance and structurally stable in the CO₂ atmosphere. However, this modification may result in reduced oxygen permeability. In this study, we investigated La_0.2Pr_0.2Nd_0.2Ba_0.2Sr_0.2Co_0.8Fe_0.2O_3-δ (L_0.2M_1.8) high-entropy perovskite materials, focusing on enhancing their oxygen permeability in both air and CO₂ atmospheres through strategic design modifications at the B-sites and A/B-sites. We prepared Ni-substituted La_0.2Pr_0.2Nd_0.2Ba_0.2Sr_0.2Co_0.7Fe_0.2Ni_0.1O_3-δ (L_0.2M_1.7N_0.1) HEPMs by introducing Ni elements at the B-site, and further innovatively introduced A-site defects to prepare La_0.2Pr_0.2Nd_0.2Ba_0.2Sr_0.2Co_0.7Fe_0.2Ni_0.1O_3-δ (L_0.1M_1.7N_0.1) materials. In a pure CO₂ atmosphere, the oxygen permeation flux of the L_0.1M_1.7N_0.1 membrane can reach 0.29 mL·cm⁻²·min⁻¹. Notably, the L_0.1M_1.7N_0.1 membrane maintained a good perovskite structure after stability tests extending up to 120 h under 20% CO₂/80% He atmosphere. These findings suggest that A-site-defect high-entropy perovskites hold great promise for applications in CO₂ capture, storage, and utilization. Full article

This study presents a simple, low-cost, and efficient route to obtain zinc oxide by adopting the thermal decomposition method of zinc acetate at 300 (Gr@ZnO_300), 400 (Gr@ZnO_400), 500 (Gr@ZnO_500), and 600 °C (Gr@ZnO_600) for 1 h. The diffraction patterns collected for the samples indicated the majority formation of the hexagonal phase (P63mc) for zinc oxide and residual amounts for graphitic carbon, which has a hexagonal structure of space group P63/mmc. The images collected by scanning electron microscopy (SEM) revealed the formation of sub-microcrystals with elongated rod-shaped morphology, with dimensions between 0.223 and 1.09 μm. The optical and colourimetric properties of the obtained materials indicate the presence of graphitic carbon in the samples, corroborating the analysis by XRD and Raman spectroscopy, with an optical bandgap close to 3.21 eV, and energies of the valence (E_VB) and conduction (E_CB) bands of 2.89 eV and −0.31 eV, respectively. The photocatalytic performance at 20 min of exposure time under UV light of all prepared samples in the decolourisation of rhodamine B (RhB) dye solutions follows the order Gr@ZnO_300 (95.6%) > Gr@ZnO_600 (92.8%) > Gr@ZnO_400 (84.0%) > Gr@ZnO_500 (78.1%), where the photocatalytic performance of Gr@ZnO_300 sample was 16.5 times more effective than the photolysis test. Moreover, the results confirmed that the best performance was archived at pH = 10, and the holes (h⁺) and superoxide (O₂^•−) radicals are the main species involved in the discolouration of RhB dye molecules in an aqueous medium. Finally, the reusability experiment shows high stability of the Gr@ZnO_300 sample as a solid photocatalyst and cycling capability, which obtained total discolouration of RhB of a solution under five cycling experiments of 60 min of exposure to UV light at room temperature. Full article

Sillenite materials have been the focus of intense research in recent years due to their unique properties and distinct structure with the I23 space group. This electronic structure has reflected high-quality applications and results for some environmental processes such as photocatalysis. This paper investigates the synthesis of a new sillenite, Bi₁₂SnO_20, and its characteristics, emphasizing its potential for photocatalytic applications. The sillenite Bi₁₂SnO₂₀ has been synthesized through the co-precipitation method by mixing the appropriate ratio of Bi and Sn ions. The obtained particles after precipitation and drying were characterized by thermogravimetric analysis (TGA) and then calcined at different temperatures based on this analysis. The phase has been identified by structural analysis using X-ray diffraction (XRD), and its morphology after identification was carried out by scanning electron microscopy (SEM). The calcination temperature has been found to have a critical role in obtaining the phase, where the phase was found to be formed at temperatures between 310 and 400 °C and changed to other phases within higher temperatures. The physicochemical properties of this sillenite were also studied by Fourier-transform infrared spectroscopy (FTIR) and UV Visible Spectrometer (UV-Vis). To study the obtained phases at different calcination temperatures, performance testing was performed under visible light to remove different contaminants, which are Tetracycline, Bisphenol A, and Rhodamine B. The phase Bi₁₂SnO₂₀ obtained at 350 °C with a catalyst dose of 1 g/L showed the highest performance for removing these pollutants with concentrations of 20 mg/L, with an efficiency of almost 100% within 2 h. This work will be useful as an important resource and strategy for the development of this sillenite material in its pure phase. Full article

To investigate and compare the changes in muscle quality of hooked, trawl-net, and radar-net hairtail (Trichiurus haumela, HH, TH, and RH) during thermal processing, the physicochemical properties of three kinds of hairtail were determined under heating at 30, 50, 70 and 90 °C for 10 min. Additionally, the muscle tissues were observed via Oil Red O (ORO) staining, Masson staining, and scanning electron microscopy (SEM). The results showed that with increased heating temperature, pH, L*, b*, chewiness, and gumminess in hairtail muscle increased, while a* and shearing force decreased. The springiness, relative contents of hydrophobic and disulfide bonds, myosin surface hydrophobicity, and TCA-soluble peptide content increased first and then decreased. However, the relative contents of ionic and hydrogen bonds showed an opposite trend. Histological observations revealed that heating disrupted hairtail muscle tissue, manifested by the blurriness and disorder of myofibrils and breakage of myofibrillar bundle membranes. The RH muscle exhibited the highest chewiness, gumminess, and chemical force levels, accompanied by the lowest content of TCA-soluble peptide. Furthermore, the RH muscle presented the greatest fat droplet content, diffusivity, and integrity of collagen and myofibers. Correlation analysis revealed a close correlation between muscle quality and protein function in HH, TH, and RH. This study provides a theoretical basis for the difference in muscle quality in three different types of hairtail. Full article

Ophiocordyceps sinensis (Berk.) is a complex is formed by Hepialidae larvae and Hirsutella sinensis. Infestation by H. sinensis, interaction with host larvae, and fruiting body development are three crucial processes affecting the formation of O. sinensis. However, research on the molecular mechanism of O. sinensis formation has been hindered by the lack of effective genetic transformation protocols. Therefore, Agrobacterium tumefaciens-mediated transformation (ATMT) was adopted to genetically transform two H. sinensis strains and optimize the transformation conditions. The results revealed that the most suitable Agrobacterium strain for H. sinensis transformation was AGL1, and that the surfactant Triton X-100 could also induce ATMT, although less effectively than acetosyringone (AS). In addition, the endogenous promoters of H. sinensis genes had a stronger ability to drive the expression of the target gene than did the exogenous promoter. The optimal transformation conditions were as follows: AS and hygromycin B concentrations of 100 μM and 50 μg/mL, respectively; A. tumefaciens OD₆₀₀ of 0.4; cocultivation at 18 °C for 24 h; and H. sinensis used within three passages. The results lay a foundation for the functional study of key regulatory genes involved in the formation of O. sinensis. Full article

A novel surface plasmon resonance (SPR) refractive index (RI) sensor based on the D-type dual-mode photonic crystal fiber (PCF) is proposed. The sensor employs a side-polished few-mode PCF that facilitates the transmission of the fundamental and second-order modes, with an integrated microfluidic channel positioned directly above the fiber core. This design minimizes the distance to the analyte and maximizes the interaction between the optical field and the analyte, thereby enhancing the SPR effect and resonance loss for improved sensing performance. Au-TiO₂ dual-layer material was coated on the surface of a microfluidic channel to enhance the penetration depth of the core evanescent field and tune the resonance wavelength to the near-infrared band, meeting the special needs of chemical and biomedical detection fields. The finite element method was utilized to systematically investigate the coupling characteristics between various modes and surface plasmon polariton (SPP) modes, as well as the impact of structural parameters on the sensor performance. The results indicate that the LP_{11b_y} mode exhibits greater wavelength sensitivity than the HE_{11_y} mode, with a maximum sensitivity of 33,000 nm/RIU and an average sensitivity of 8272.7 nm/RIU in the RI sensing range of 1.25–1.36, which is higher than the maximum sensitivity of 16,000 nm/RIU and average sensitivity of 5666.7 nm/RIU for the HE_{11b_y} mode. It is believed that the proposed PCF-SPR sensor features both high sensitivity and high resolution, which will become a critical device for wide RI detection in mid-infrared fields. Full article