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A method for simultaneous determination of 53 anti-infective drugs such as quinolones and sulfonamides in cosmetics was established by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/ MS). The samples were dispersed with saturated sodium chloride, extracted by ultrasound with 1% acetonitrile formate solution, and centrifuged. 0.1% Formic acid aqueous solution (containing 1 mmol/L ammonium acetate) and 0.1% formic acid methanol solution were chose as mobile phase, gradient elution was used, and electrospray ion source, positive ion multi-reaction monitoring mode (MRM) were used for determination with quantitative external standard method. The results show that the linear fitting of the 53 banned raw materials is good, with the correlation coefficient greater than 0.991 0, and the detection limit of 0.01-0.1 μg/g. The average recovery rates of sulfonamides and quinolones are 80.84% to 115.09% at low, medium, and high spiked mass concentrations. Among the 100 batches of samples screened, 1 batch is detected to contain sulfamethoxazole. The method has good sensitivity, selectivity and accuracy, and can be used for the determination of 53 anti-infective drugs in cosmetics. [ABSTRACT FROM AUTHOR]

Streptococcus equi subsp. zooepidemicus (SEZ) is an opportunistic pathogen of both humans and animals. Quorum sensing (QS) plays an important role in the regulation of bacterial group behaviors. The aim of this study was to characterize the LuxS in SEZ and evaluate its impact on biofilm formation, pathogenesis and gene expression. The wild-type SEZ and its LuxS mutant (DluxS) were examined for growth, biofilm formation, virulence factors, and transcriptomic profiles. Our results showed that LuxS deficiency did not affect SEZ hemolytic activity, adhesion or capsule production. For biofilm assay demonstrated that mutation in the luxS gene significantly enhances biofilm formation, produced a denser biofilm and attached to a glass surface. RAW264.7 cell infection indicated that DluxS promoted macrophage apoptosis and pro-inflammatory responses. In mice infection, there was no significant difference in mortality between SEZ and DluxS. However, the bacterial load in the spleen of mice infected with DluxS was significantly higher than in those infected with SEZ. And the pathological analysis further indicated that spleen damage was more severe in the DluxS group. Moreover, transcriptomics analysis revealed significant alterations in carbon metabolism, RNA binding and stress response genes in DluxS. In summary, this study provides the first evidence of AI-2/LuxS QS system in SEZ and reveals its regulatory effects on biofilm formation, pathogenicity and gene expression. [ABSTRACT FROM AUTHOR]

A systematic study was carried out on 638 wheat and paddy grains (including fresh and stored samples) collected in 2021 from Shanghai, China, to identify the major mycobiota and their toxigenic abilities. A total of 349 fungi, namely, 252 Fusarium, 53 Aspergillus, and 44 Alternaria, were characterized by morphological and molecular identification. Fusarium and Aspergillus were more frequently isolated in paddy with Fusarium sambucinum species complex and Aspergillus section flavi as the predominant species, respectively. The genus Alternaria was the most frequently isolated fungal species in wheat. The toxin-producing potentials of the identified fungi were further evaluated in vitro. Deoxynevalenol (DON) was produced by 34.5% of Fusarium isolates and zearalenone (ZEN) was produced by 47.6% of them, and one isolate also processed the abilities for fumonisin B1 (FB1), B2 (FB2), and B3 (FB3) productions. Aflatoxin B1 (AFB1), B2 (AFB2), and G1 (AFG1) were only generated by Aspergillus section flavi, with the production rate of 65.5%, 27.6%, and 13.8%, respectively. Alternariol (AOH) was the most prevalent Alternaria toxin, which could be produced by 95.5% of the isolates, followed by alternariol monomethyl ether (AME) (72.7%), altenuene (ALT) (52.3%), tenuazonic acid (TeA) (45.5%), tentoxin (TEN) (29.5%), and altenusin (ALS) (4.5%). A combinational analysis of mycobiota and toxigenic ability allowed us to provide comprehensive information about the production mechanisms of mycotoxins in wheat and paddy in a specific geographic area, and will be helpful for developing efficient prevention and control programs. [ABSTRACT FROM AUTHOR]

The study aims to examine the associations between social contact pattern changes and mental health status, including depression, anxiety, and loneliness, among Chinese adults in the context of coronavirus disease 2019 (COVID-19). Data on social contact patterns before and after the outbreak of COVID-19 were obtained from 3511 participants. Mental health (ie, depression, anxiety, and loneliness) was assessed by the 9-item Patient Health Questionnaire, Dark Future Scale, and the 9-scale Three-Item Loneliness Scale, respectively. Poisson regression analyses revealed that the participants who had increased in-person communication were more likely to have mental disorders [depression: prevalence ratio (PR)=1.13, 95% confidence interval (CI): 1.02, 1.26; anxiety: PR=1.15, 95% CI: 1.01, 1.30]. The current study concluded that the in-person communication increase before and after the outbreak of COVID-19 was associated with mental disorders among Chinese adults. [ABSTRACT FROM AUTHOR]

Introduction: Delayed neurocognitive recovery (DNR) is a common post-surgical complication among the elderly. Cognitive frailty (CF) is also an age-related medical syndrome. However, little is known about the association between CF and DNR. Therefore, this study aimed to study whether CF is associated with DNR in elderly patients undergoing elective noncardiac surgery, as well as to explore the potential risk factors for DNR in frail elderly individuals and construct a prediction model. Methods: This prospective cohort study administered a battery of cognitive and frailty screening instruments for 146 individuals (≥65 years old) scheduled for elective noncardiac surgery. Screening for CF was performed at least one day before surgery, and tests for the presence of DNR were performed seven days after surgery. The association between CF and DNR was investigated. Moreover, the study subjects were randomly divided into a modeling group (70%) and a validation group (30%). Univariate and multivariate logistic regression was performed to analyze the modeling group data and identify the independent risk factors for DNR. The R software was used to construct DNR's nomogram model, verifying the model. Results: In total, 138 individuals were eligible. Thirty-three cases were diagnosed with DNR (23.9%). No significant difference in the number of patients with CF was observed between the DNR and non-DNR groups (P > 0.05). Multivariate analysis after adjusting relevant risk factors showed that only the judgment of line orientation (JLOT) test score significantly affected the incidence of DNR. After internal validation of the constructed DNR prediction model, the area under the curve (AUC) of the forecast probability for the modeling population (n=97) for DNR was 0.801, and the AUC for the validation set (n = 41) was 0.797. The calibration curves of both the modeling and validation groups indicate that the prediction model has good stability. Conclusion: Cognitive frailty is not an independent risk factor in predicting DNR after noncardiac surgery in frail elderly individuals. The preoperative JLOT score is an independent risk factor for DNR in frail elderly individuals. The prediction model has a good degree of discrimination and calibration, which means that it can individually predict the risk probability of DNR in frail elderly individuals. [ABSTRACT FROM AUTHOR]

In this paper, a miniaturized Vivaldi antenna for C- to X-bands is proposed and fabricated. An H-Shaped Resonator (HSR) and transverse slot structures are employed in this design, which improve the gain through the entire band, especially at the high frequency band. These simulated results show that the modified Vivaldi antenna has a maximum gain increment of 4 dBi and peak gain of 9.9 dBi. Furthermore, the modified Vivaldi antenna has narrower half-power beam width (HPBW), higher front-to-back ratio (FBR) and better radiation characteristics. The measured results are in good agreement with the simulated ones. [ABSTRACT FROM AUTHOR]

In the embryonic CNS, development ofmyelin-forming oligodendrocytes is limited by bone morphogenetic proteins, which constitute one arm of the transforminggrowth factor-β (Tgfβ) familyand signal canonically via Smads 1/5/8.Tgfβ ligands andActivins comprisethe otherarmandsignal via Smads 2/3, but their roles in oligodendrocyte development are incompletely characterized. Here, we report that Tgfβ ligands and activin B (ActB) act in concert in the mammalian spinal cord to promote oligodendrocyte generation andmyelination. Inmouse neural tube, newly specified oligodendrocyte progenitors (OLPs) are first exposed to Tgfβ ligands in isolation, then later in combinationwith ActB during maturation. In primary OLP cultures, Tgfβ1 and ActB differentially activate canonical Smad3 and non-canonicalMAP kinase signaling. Both ligands enhance viability, andTgfβ1 promotes proliferationwhileActBsupportsmaturation. Importantly, co-treatment strongly activates both signaling pathways, producing an additive effect on viability and enhancing both proliferation and differentiation such that mature oligodendrocyte numbers are substantially increased. Co-treatment promotes myelination in OLPneuron co-cultures, and maturing oligodendrocytes in spinal cord white matter display strong Smad3 and MAP kinase activation. In spinal cords of ActB-deficient Inhbb-l- embryos, apoptosis in the oligodendrocyte lineage is increased andOLPnumbers transiently reduced, butnumbers, maturation and myelination recover during the first postnatal week. Smad3-l- mice display a more severe phenotype, including diminished viability and proliferation, persistently reduced mature and immature cell numbers, and delayed myelination. Collectively, these findings suggest that, in mammalian spinal cord, Tgfβ ligands and ActB together support oligodendrocyte development and myelin formation. [ABSTRACT FROM AUTHOR]

Multiple sclerosis is an inflammatory demyelinating disease of the brain and spinal cord with a presumed autoimmune etiology. Conduction block in demyelinated axons underlies early neurological symptoms, whereas axonal transection is believed responsible for more permanent later deficits. Approved treatments for the disease are immunoregulatory and reduce the rate of lesion formation and clinical exacerbation, but are only partially effective in preventing the onset of disability in multiple sclerosis patients. Approaches that directly protect myelin-producing oligodendrocytes and enhance remyelination may improve long-term outcomes and reduce the rate of axonal transection. Studies in genetically modified animals have improved our understanding of mechanisms underlying central nervous system pathology in multiple sclerosis models, and have identified pathways that regulate oligodendrocyte viability and myelin repair. However, although clinical trials are ongoing, many have been unsuccessful, and no treatments are yet approved that target these areas in multiple sclerosis. In this review, we examine avenues for oligodendrocyte protection and endogenous myelin repair in animal models of demyelination and remyelination, and their relevance as therapeutics in human patients. © 2011 Mount Sinai School of Medicine [ABSTRACT FROM AUTHOR]