Antibacterial activity and mechanism of sanguinarine against Staphylococcus aureus by interfering with the permeability of the cell wall and membrane and inducing bacterial ROS production

Staphylococcus aureus (SA) is representative of gram-positive bacteria. Sanguinarine chloride hydrate (SGCH) is the hydrochloride form of sanguinarine (SG), one of the main extracts of Macleaya cordata (M. cordata). There are few reports on its antibacterial mechanism against SA. Therefore, in this study, we investigated the in vitro antibacterial activity and mechanism of SGCH against SA. The inhibitory zone, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were measured, and the bactericidal activity curve was plotted. In addition, the micromorphology, alkaline phosphatase (AKP) activity, Na+K+, Ca2+Mg2+-adenosine triphosphate (ATP) activity, intracellular reactive oxygen species (ROS), and fluorescein diacetate (FDA) were observed and detected. The results showed that the inhibitory zone of SGCH against SA was judged as medium-sensitive; the MIC and MBC were 128 and 256 μg/mL, respectively; in the bactericidal activity curve, SGCH with 8 × MIC could completely kill SA within 24 h. SGCH was able to interfere with the integrity and permeability of the SA cell wall and membrane, as confirmed by the scanning electron microscopy (SEM) images, the increase in extracellular AKP and Na+ K+, Ca2+ Mg2+-ATP activities as well as the fluorescein diacetate (FDA) staining experiment results. Moreover, a high concentration of SGCH could induce SA to produce large amounts of ROS. In summary, these findings revealed that SGCH has a preferable antibacterial effect on SA, providing an experimental and theoretical basis for using SG as an antibiotic substitute in animal husbandry and for the clinical control and treatment of diseases caused by SA

Methodology and experiences of rapid advice guideline development for children with COVID-19: responding to the COVID-19 outbreak quickly and efficiently

BACKGROUND: Rapid Advice Guidelines (RAG) provide decision makers with guidance to respond to public health emergencies by developing evidence-based recommendations in a short period of time with a scientific and standardized approach. However, the experience from the development process of a RAG has so far not been systematically summarized. Therefore, our working group will take the experience of the development of the RAG for children with COVID-19 as an example to systematically explore the methodology, advantages, and challenges in the development of the RAG. We shall propose suggestions and reflections for future research, in order to provide a more detailed reference for future development of RAGs. RESULT: The development of the RAG by a group of 67 researchers from 11 countries took 50 days from the official commencement of the work (January 28, 2020) to submission (March 17, 2020). A total of 21 meetings were held with a total duration of 48 h (average 2.3 h per meeting) and an average of 16.5 participants attending. Only two of the ten recommendations were fully supported by direct evidence for COVID-19, three recommendations were supported by indirect evidence only, and the proportion of COVID-19 studies among the body of evidence in the remaining five recommendations ranged between 10 and 83%. Six of the ten recommendations used COVID-19 preprints as evidence support, and up to 50% of the studies with direct evidence on COVID-19 were preprints. CONCLUSIONS: In order to respond to public health emergencies, the development of RAG also requires a clear and transparent formulation process, usually using a large amount of indirect and non-peer-reviewed evidence to support the formation of recommendations. Strict following of the WHO RAG handbook does not only enhance the transparency and clarity of the guideline, but also can speed up the guideline development process, thereby saving time and labor costs

Methodology and experiences of rapid advice guideline development for children with COVID-19: responding to the COVID-19 outbreak quickly and efficiently.

BACKGROUND Rapid Advice Guidelines (RAG) provide decision makers with guidance to respond to public health emergencies by developing evidence-based recommendations in a short period of time with a scientific and standardized approach. However, the experience from the development process of a RAG has so far not been systematically summarized. Therefore, our working group will take the experience of the development of the RAG for children with COVID-19 as an example to systematically explore the methodology, advantages, and challenges in the development of the RAG. We shall propose suggestions and reflections for future research, in order to provide a more detailed reference for future development of RAGs. RESULT The development of the RAG by a group of 67 researchers from 11 countries took 50 days from the official commencement of the work (January 28, 2020) to submission (March 17, 2020). A total of 21 meetings were held with a total duration of 48 h (average 2.3 h per meeting) and an average of 16.5 participants attending. Only two of the ten recommendations were fully supported by direct evidence for COVID-19, three recommendations were supported by indirect evidence only, and the proportion of COVID-19 studies among the body of evidence in the remaining five recommendations ranged between 10 and 83%. Six of the ten recommendations used COVID-19 preprints as evidence support, and up to 50% of the studies with direct evidence on COVID-19 were preprints. CONCLUSIONS In order to respond to public health emergencies, the development of RAG also requires a clear and transparent formulation process, usually using a large amount of indirect and non-peer-reviewed evidence to support the formation of recommendations. Strict following of the WHO RAG handbook does not only enhance the transparency and clarity of the guideline, but also can speed up the guideline development process, thereby saving time and labor costs

Identification of Mycobacterium tuberculosis-Specific Th1, Th17 and Th22 Cells Using the Expression of CD40L in Tuberculous Pleurisy

Important advances have been made in the immunodiagnosis of tuberculosis (TB) based on the detection of Mycobacterium tuberculosis (MTB)-specific T cells. However, the sensitivity and specificity of the immunological approach are relatively low because there are no specific markers for antigen-specific Th cells, and some of the Th cells that do not produce cytokines can be overlooked using this approach. In this study, we found that MTB-specific peptides of ESAT-6/CFP-10 can stimulate the expression of CD40L specifically in CD4+ T cells but not other cells from pleural fluid cells (PFCs) in patients with tuberculous pleurisy (TBP). CD4+CD40L+ but not CD4+CD40L− T cells express IFN-γ, IL-2, TNF-α, IL-17 or IL-22 after stimulation with MTB-specific peptides. In addition, CD4+CD40L+ T cells were found to be mostly polyfunctional T cells that simultaneously produce IFN-γ, IL-2 and TNF-α and display an effector or effector memory phenotype (CD45RA−CD45RO+CCR7−CD62L−ICOS−). To determine the specificity of CD4+CD40L+ T cells, we incubated PFCs with ESTA-6/CFP-10 peptides and sorted live CD4+CD40L+ and CD4+CD40L− T cells by flow cytometry. We further demonstrated that sorted CD4+CD40L+, but not CD4+CD40L− fractions, principally produced IFN-γ, IL-2, TNF-α, IL-17 and IL-22 following restimulation with ESTA-6/CFP-10 peptides. Taken together, our data indicate that the expression of CD40L on MTB-specific CD4+ T cells could be a good marker for the evaluation and isolation of MTB-specific Th cells and might also be useful in the diagnosis of TB

Régularisation spatiale de représentations distribuées de mots

Stimulée par l’usage intensif des téléphones mobiles, l’exploitation conjointe des don-nées textuelles et des données spatiales présentes dans les objets spatio-textuels (p. ex. tweets)est devenue la pierre angulaire à de nombreuses applications comme la recherche de lieux d’attraction. Du point de vue scientifique, ces tâches reposent de façon critique sur la représentation d’objets spatiaux et la définition de fonctions d’appariement entre ces objets. Dans cet article,nous nous intéressons au problème de représentation de ces objets. Plus spécifiquement, confortés par le succès des représentations distribuées basées sur les approches neuronales, nous proposons de régulariser les représentations distribuées de mots (c.-à-d. plongements lexicaux ou word embeddings), pouvant être combinées pour construire des représentations d’objets,grâce à leurs répartitions spatiales. L’objectif sous-jacent est de révéler d’éventuelles relations sémantiques locales entre mots ainsi que la multiplicité des sens d’un même mot. Les expérimentations basées sur une tâche de recherche d’information qui consiste à retourner le lieu physique faisant l’objet (sujet) d’un géo-texte montrent que l’intégration notre méthode de régularisation spatiale de représentations distribuées de mots dans un modèle d’appariement de base permet d’obtenir des améliorations significatives par rapport aux modèles de référence

Efficient Photoluminescence of Mn 2+ -Doped ZnS Quantum Dots Sensitized by Hypocrellin A

Mn 2+ -doped ZnS semiconductor quantum dots reveal remarkably intense photoluminescence with the 4 T 1 (4G) f 6 A 1 (6S) transition. In this study, following growth doping technique, Mn 2+ -doped ZnS quantum dots (ZnS:Mn 2+ QDs) with high-quality optical properties and narrow size distribution were synthesized successfully. The dopant emission has been optimized with various reaction parameters, and it has been found that the percentage of introduced dopant, reaction temperature, and time as well as the pH of a reaction mixture are key factors for controlling the intensity. Photoluminescence emission (PL) measurements of ZnS:Mn 2+ QDs show Mn 2+ d-d orange luminescence along with band-edge blue luminescence. Moreover, the electron transfer from singlet states of hypocrellin A (HA) to colloidal ZnS:Mn 2+ QDs has been examined by absorption spectra and fluorescence quenching. The absorption spectrum gave an evidence of the increases in the extinction coefficient and the red-shift of the absorption maxima in the absorption spectra of HA in the presence of ZnS:Mn 2+ QDs, demonstrating the occurrence of surface interactions between the sensitizer and the particle surface. Fluorescence quenching by ZnS:Mn 2+ QDs also suggested that there were a complex association between HA and ZnS:Mn 2+ QDs, which was necessary for observing the heterogeneous electron-transfer process at the interface of sensitizer-semiconductor

Identification of M.tuberculosis-Specific Th1 Cells Expressing CD69 Generated in vivo in Pleural Fluid Cells from Patients with Tuberculous Pleurisy

Th1 cell-mediated immune responses at the site of active infection are important to restrict the growth of M.tuberculosis (MTB) and for the spontaneous resolution of patients with tuberculous pleurisy (TBP). In the present study, we found that without any stimulation, CD4 + T cells in pleural fluid cells (PFCs) from patients with TBP expressed significantly higher levels of CD69 than PBMCs from patients with tuberculosis (TB) or healthy donors. CD4 + CD69 + T cells expressed T-bet and IL-12Rb2. After stimulation with MTB-specific antigens, CD4 + CD69 + T cells expressed significantly higher levels of IFN-c, IL-2 and TNF-a than CD4 + CD69 2 T cells, demonstrating that CD4 + CD69 + T cells were MTB-specific Th1 cells. In addition, CD4 + CD69 + T cells were mostly polyfunctional Th1 cells that simultaneously produced IFN-c, IL-2, TNF-a and displayed an effector or effector memory phenotype (CD45RA 2 CCR7 2 CD62L 2 CD27 2). Moreover, the percentages of CD4 + CD69 + T cells were significantly and positively correlated with polyfunctional T cells. Interestingly, sorted CD4 + CD69 + but not CD4 + CD69 2 fractions by flow cytometry produced IFN-c, IL-2 and TNF-a that were significantly regulated by CD4 + CD25 + Treg cells. Taken together, based on the expression of CD69, we found a direct quantitative and qualitative method to detect and evaluate the in vivo generated MTB-specific polyfunctional CD4 + T cells in PFCs from patients with TBP. This method can b

Experimental Study on the Treatment of 1, 4 butanediol Mixed Wastewater by Ferro-carbon Micro-electrolysis

The mixed wastewater of 1, 4 butanediol was tested with iron filings and carbon powder as catalyst by aeration to provide oxygen. The effects of carbon powder, pH value and reaction time on wastewater treatment were studied. The optimal experimental condition was that the mesh number of activated carbons was 20, the pH value was 5, the reaction time was 30min, and the Chemical Oxygen Demand (COD) removal efficiency reached 36.2%. At the same time, The response surface method was used to analyze and optimize the experimental results, and the relation formula of each influencing factor on removal efficiency was established, and the order of influence degree of each factor on removal efficiency (pH> activated carbon mesh number > reaction time) was obtained, in which pH had the greatest influence on the treatment rate of ferro-carbon micro-electrolysis treatment of 1, 4-butanediol wastewater

Efficient Photoluminescence of Mn2+-Doped ZnS Quantum Dots Sensitized by Hypocrellin A

Mn2+-doped ZnS semiconductor quantum dots reveal remarkably intense photoluminescence with the 4T1(4G) f6A1(6S) transition. In this study, following growth doping technique, Mn2+-doped ZnS quantum dots (ZnS:Mn2+ QDs) with high-quality optical properties and narrow size distribution were synthesized successfully. The dopant emission has been optimized with various reaction parameters, and it has been found that the percentage of introduced dopant, reaction temperature, and time as well as the pH of a reaction mixture are key factors for controlling the intensity. Photoluminescence emission (PL) measurements of ZnS:Mn2+ QDs show Mn2+ d-d orange luminescence along with band-edge blue luminescence. Moreover, the electron transfer from singlet states of hypocrellin A (HA) to colloidal ZnS:Mn2+ QDs has been examined by absorption spectra and fluorescence quenching. The absorption spectrum gave an evidence of the increases in the extinction coefficient and the red-shift of the absorption maxima in the absorption spectra of HA in the presence of ZnS:Mn2+ QDs, demonstrating the occurrence of surface interactions between the sensitizer and the particle surface. Fluorescence quenching by ZnS:Mn2+ QDs also suggested that there were a complex association between HA and ZnS:Mn2+ QDs, which was necessary for observing the heterogeneous electron-transfer process at the interface of sensitizer-semiconductor

Research on the spatial correlation and formation mechanism between traditional villages and rural tourism

Abstract In recent years, the survival and development of traditional villages in China have been serious challenges. Rural tourism is regarded as an important way to solve rural problems, and the combination of rural culture and tourism has become a new power point for rural development. Therefore, it is necessary to explore the spatial distribution structure between traditional villages and rural tourism. In this paper, rural tourism was represented by the rural tourism characteristic village (RTCV), and Henan Province, China, was taken as a study area to analyze the distribution pattern and spatial correlation of rural tourism and traditional village (TV) and discuss the relationship between the spatial correlation and regional natural environment and socioeconomic factors. The results show that the coupling of the spatial correlation between RTCVs and TVs in Henan was clear. They could be divided into 5 regions based on geographical factors. In addition, the research summarized 4 typical spatial structures between TVs and RTCVs in Henan based on the regional symbiosis theory, and the spatial pattern formation mechanism of TVs and RTCVs was discussed based on three driving mechanisms. The spatial structure of the two can provide reference value for other developing countries and regions to achieve sustainable rural development