ABSTRACT
Herein, an improved subtraction model was proposed to characterise the polar stationary phases in supercritical fluid chromatography (SFC). Fifteen stationary phases were selected, including two types of aromatic columns, Waters Torus and Viridis series columns, as well as silica and amino columns. Ethylbenzene and Torus 1-AA were defined as the reference solute and column, respectively. Identifying the interaction with the maximum contribution to retention in SFC separation and using it as the initial term is a key step in modelling. The dipole, or induced dipole interaction (θ'P), replaced the hydrophobic interaction (η'H) as the starting term. The improved model was expressed as logα=η'H+ß'A+α'B+κ'C+θ'P+ε'E+σ'S, where the term ε'E indicated that anion exchange interaction was intentionally supplemented. A 7-step modelling process, including bidirectional fitting and residual analysis, was proposed. The obtained column parameters had reasonable physical significance, with the adjusted determination coefficient (R2adj) greater than 0.999 and the standard error (SE) less than 0.029. Methodological validation was further performed using the other four columns and 12 solutes that were not involved in the modelling. The result revealed good predictions of solutes' retention, as demonstrated by R2adj from 0.9923 to 0.9979 and SE from 0.0636 to 0.1088. This study indicated the feasibility of using the improved subtraction model to characterise polar stationary phases in SFC, with the most crucial being the determination of an initial term, followed by the addition of a new descriptor and the selection of an appropriate reference column. The study expanded the application scope of the subtraction model in SFC, which will help gain an in-depth understanding of the SFC separation mechanism.
Subject(s)
Chromatography, Supercritical Fluid , Hydrophobic and Hydrophilic Interactions , Chromatography, Supercritical Fluid/methods , Models, Chemical , Benzene Derivatives/chemistry , Silicon Dioxide/chemistryABSTRACT
Sleep is a vital component of health; however, sleep issues are particularly prominent among college students. Identifying protective factors for sleep among college students is of paramount importance. To investigate the mechanisms behind the association between the presence of meaning in life (PML) and sleep quality, we conducted two questionnaire surveys (separated by an interval of 6 months) with 5660 college students to collect longitudinal data. The results show that PML predicted sleep quality and that this relationship was influenced by the mediating effect of depression and the chain mediating effect of coping style and depression; further, the search for meaning in life played a moderating role in the chain mediation model. This study offers new theoretical perspectives on the protective factors of sleep quality and provides empirical insights useful for improving sleep health among college students.
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Background: The microbiome plays a pivotal role in mediating immune deviation during the development of early-life viral infections. Recurrent infections in children are considered a risk factor for disease development. This study delves into the metagenomics of the microbiome in children suffering from severe infections, seeking to identify potential sources of these infections. Aims: The aim of this study was to identify the specific microorganisms and factors that significantly influence the treatment duration in patients suffering from severe infections. We sought to understand how these microbial communities and other variables may affect the treatment duration and the use of antibiotics of these patients with severe infections. Method: Whole-genome shotgun sequencing was conducted on samples collected from children aged 0-14 years with severe infections, admitted to the Pediatrics Department of Xiamen First Hospital. The Kraken2 algorithm was used for taxonomic identification from sequence reads, and linear mixed models were employed to identify significant microorganisms influencing treatment duration. Colwellia, Cryptococcus, and Citrobacter were found to significantly correlate with the duration of clinical treatment. Further analysis using propensity score matching (PSM) and rank-sum test identified clinical indicators significantly associated with the presence of these microorganisms. Results: Using a linear mixed model after removed the outliers, we identified that the abundance of Colwellia, Cryptococcus, and Citrobacter significantly influences the treatment duration. The presence of these microorganisms is associated with a longer treatment duration for patients. Furthermore, these microorganisms were found to impact various clinical measures. Notably, an increase in hospitalization durations and medication costs was observed in patients with these microorganisms. In patients with Colwellia, Cryptococcus, and Citrobacter, we discover significant differences in platelets levels. We also find that in patients with Cryptococcus, white blood cells, hemoglobin, and neutrophils levels are lower. Conclusion: These findings suggest that Colwellia, Cryptococcus, and Citrobacter, particularly Cryptococcus, could potentially contribute to the severity of infections observed in this cohort, possibly as co-infections. These microorganisms warrant further investigation into their pathogenic roles and mechanisms of action, as their presence in combination with disease-causing organisms may have a synergistic effect on disease severity. Understanding the interplay between these microorganisms and pathogenic agents could provide valuable insights into the complex nature of severe pediatric infections and guide the development of targeted therapeutic strategies.
ABSTRACT
In the last decade, the separation application based on aromatic stationary phases has been demonstrated in supercritical fluid chromatography (SFC). In this paper, four aromatic stationary phases involving aniline (S-aniline), 1-aminonaphthalene (S-1-ami-naph), 1-aminoanthracene (S-1-ami-anth) and 1-aminopyrene (S-1-ami-py) were synthesized based on full porous particles (FPP) silica, which were not end-capped for providing extra electrostatic interaction. Retention mechanism of these phases in SFC was investigated using a linear solvation energy relationship (LSER) model. The aromatic stationary phases with five positive parameters (a, b, s, e and d+) can provide hydrogen bonding, π-π, dipole-dipole and cation exchange interactions, which belong to the moderate polar phases. The LSER results obtained using routine test solutes demonstrated that the aforementioned interactions of four aromatic stationary phases were influenced by the type and bonding density of the ligand, but to a certain extent. Furthermore, the LSER data verified that the S-1-ami-anth column based on full porous particles silica had higher cation exchange capacity (d+ value), compared to the commercialized 1-AA column (based on the ethylene-bridged hybrid particles). The relationship between the d+ value and SFC additive was quantitatively proved so as to regulate electrostatic interaction reasonably. This value was greatly increased by phosphoric acid, slightly increased by trifluoroacetic acid and formic acid, but significantly reduced by ammonium formate and diethylamine. Taking the S-1-ami-naph column as an example, better peek shape of the flavonoids was obtained after the addition of 0.1 % phosphoric acid in MeOH while isoquinoline alkaloids were eluted successfully within 11 min after adding 0.1 % diethylamine in MeOH. Combined with the unique π-π interaction and controllable electrostatic interaction, the aromatic stationary phases in this study have been proven to have expandable application potential in SFC separation.
Subject(s)
Chromatography, Supercritical Fluid , Phosphoric Acids , Chromatography, Supercritical Fluid/methods , Silicon Dioxide/chemistry , Cations , Aniline Compounds , DiethylaminesABSTRACT
BACKGROUND: Asthma is the most common allergic disease characterized by an inflammatory response in the airways. Mechanismly, urban particulate matter (PM) is the most widely air pollutant associated with increased asthma morbidity and airway inflammation. Current research found that vitamin D is an essential vitamin with anti-inflammatory, antioxidant and other medical efficacy. Inadequate or deficient vitamin D often leads to the pathogenesis and stability of asthma. NGF exacerbates airway inflammation in asthma by promoting smooth muscle cell proliferation and inducing the Th2 immune response. Activation of the Nrf2/HO-1 signaling pathway can exert a protective effect on the inflammatory response in bronchial asthma. However, the specific mechanism of this pathway in PM-involved asthmatic airway smooth muscle cells remains unclear. METHODS: Mice were sensitized and challenged with Ovalbumin (OVA) to establish an asthma model. They were then exposed to either PM, vitamin D or a combination of both, and inflammatory responses were observed. Including, acetylcholine stimulation at different concentrations measured airway hyperresponsiveness in mice. Bronchoalveolar lavage fluid (BALF) and serum were collected for TNF-α, IL-1ß, IL-6, and Nerve growth factor (NGF) analysis. Additionally, lung tissues underwent histopathological examination to observe alveolar structure and inflammatory cell infiltration. Specific ELISA kits were utilized to determine the levels of the inflammatory factors TNF-α, IL-1ß, IL-6, and Nerve growth factor (NGF). Nrf2/HO-1 signaling pathways were examined by western blot analysis. Meanwhile, we constructed a cell system with low HO-1 expression by lentiviral transfection of airway smooth muscle cells. The changes of Nrf2, HO-1, and NGF were observed after the treatment of OVA, PM, and Vit D were given. RESULTS: The in vivo results showed that vitamin D significantly alleviated pathological changes in lung tissue of PM-exposed mice models. Mechanismly, vitamin D decreased substantial inflammatory cell infiltration in lung tissue, as well as the number of inflammatory cells in BALF. Furthermore, vitamin D reduced the heightened inflammatory factors including of TNF-α, IL-1ß, IL-6, and NGF caused by PM exposure, and triggered the activity of nucleus Nrf2 and HO-1 in PM-exposed asthmatic mice. Notably, knockdown HO-1 weakens the Vitamin D- mediated inhibition to pollution toxicity in asthma. Importantly, in vitro experiments on OVA-stimulated mice airway smooth muscle cells, the results showed that OVA and PM, respectively, reduced Nrf2/HO-1 and increased NGF's expression, while vitamin D reversed the process. And in the HO-1 knockdown cell line of Lenti-si-HO-1 ASMCs, OVA and PM reduced Nrf2's expression, while HO-1 and NGF's expression were unchanged. CONCLUSIONS: The above results demastrate that vitamin D downregulated the inflammatory response and the expression of NGF by regulating the Nrf2/HO-1 signaling pathways in airway smooth muscle cells, thereby showing potent anti-inflammatory activity in asthma.
Subject(s)
Asthma , Particulate Matter , Mice , Animals , Particulate Matter/toxicity , NF-E2-Related Factor 2/metabolism , Vitamin D/pharmacology , Vitamin D/therapeutic use , Tumor Necrosis Factor-alpha/metabolism , Interleukin-6/metabolism , Nerve Growth Factor/metabolism , Nerve Growth Factor/pharmacology , Nerve Growth Factor/therapeutic use , Asthma/chemically induced , Asthma/drug therapy , Lung/pathology , Inflammation , Signal Transduction , Bronchoalveolar Lavage Fluid , Anti-Inflammatory Agents/pharmacology , Vitamins/therapeutic use , Ovalbumin , Disease Models, Animal , Mice, Inbred BALB C , Cytokines/metabolismABSTRACT
The development of an approach based on simultaneous supercritical fluid extraction-sample cleanup, followed by supercritical fluid chromatography/tandem mass spectrometry (SFE-SFC-MS/MS) was as a tool for the extraction, separation and characterization of indole alkaloids of Uncaria rhynchophylla. A two-step SFE method was designed. A mixture of the U. rhynchophylla sample and an adsorbent named C18SCX with the ratio of 1:1 (w/w) was placed into an extraction cell. The extraction temperature was 40 °C and the pressure was 25 Mpa. In the first step, 10 % EtOH as the co-solvent was used to extract for 60 min, which was considered as a cleanup process to remove non-alkaloid components. In the second step, 0.1 % DEA was added to 10 % EtOH and it extracted for 60 min to obtain the desired extract. By introducing an additional adsorbent, the specificity of SFE towards alkaloids was greatly improved. An SFC-MS/MS method was then utilized for analysis of the SFE extract. Using 2-EP as stationary phase with the gradient elution of 0-10 min, 5-25 % EtOH (+0.05 % DEA) in CO2, column temperature 40 °C, and back pressure 13.8 Mpa, 10 peaks were separated within 8 min. Further MS/MS analysis confirmed that nine of the 10 peaks in the SFE extract were indole alkaloids. This study developed a supercritical fluid-based method specifically towards extraction and analysis of alkaloids, which is helpful to the study of alkaline compounds in complex samples.
ABSTRACT
We report on a novel, to the best of our knowledge, active probe for scanning near-field optical microscopy (SNOM). A fluorescent nanosphere, acting as the secondary source, is grafted in an electrostatic manner at the apex of a polymer tip integrated into the extremity of an optical fiber. Thanks to the high photostability and sensitivity of the secondary source, the near-field interaction with a gold nanocube is investigated. It is shown that the spatial resolution is well defined by the size of the fluorescent nanosphere. The polarization-dependent near-field images, which are consistent with the simulation, are ascribed to the local excitation rate enhancement. Meanwhile, measurement of the distance-dependent fluorescence lifetime of the nanosphere provides strong evidence that the local density of states is modified so that extra information on nano-emitters can be extracted during near-field scanning. This advanced active probe can thus potentially broaden the range of applications to include nanoscale thermal imaging, biochemical sensors, and the manipulation of nanoparticles.
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Introduction: Suicide is a major social and public health problem in the world. It is important to identify protective and risk factors for suicide. This study aimed to investigate the relationship between self-compassion and suicide risk. Methods: 1143 college students were surveyed by using Chinese Self-Compassion Scale (CSCS), Depression Anxiety Stress Scale-21 Chinese Version (DASS-21), Connor-Davidson Resilience Scale (CD-RISC), and Suicidal Behaviors Questionnaire-Revised (SBQ-R). Results: Negative self-compassion had a significant positive predictive effect on college students' suicide risk; in the model of negative self-compassion affecting suicide risk, negative emotions played a mediating role and the mediating role was moderated by resilience. Specifically, compared with low resilience, students with high resilience have a weaker ability to predict suicide risk by negative emotions. Discussion: Negative self-compassion is a risk factor for suicide risk, reducing negative self-compassion (self-judgment, isolation, and over-identification) and enhancing resilience has a guiding effect on suicide prevention and intervention.
ABSTRACT
The present paper illustrates the versatility of the supercritical fluid chromatography (SFC) since, for the first time, four spirooxindole alkaloids (SOAs) including two pairs of isomers were separated by using two types of reversed-phase/ ion chromatography (RP/IC) mixed-mode stationary phases. Two mixed-mode stationary phases (C8SAX and C8SCX) was simultaneously provided dispersive and electrostatic interactions, which were suitable for the separation of such alkaloids. This study tried to provide an in-depth understanding of the SFC separation mechanism of the mixed-mode stationary phase through investigation of the impact of changes in mobile phase composition on alkaloids' retention behavior. On C8SAX, due to the strong electrostatic repulsion, there was a very narrow elution window of the alkaloids, of which behaviors were hardly affected by adding diethylamine in mobile phase. When adding formic acid or acidic ammonium formate, the prolonged retention time of alkaloids was presented because of the shielded effect of formate anions on the electrostatic repulsion. In particular, better peak shape and improved resolution were obtained by using acidic ammonium formate due to the deactivation of silanol groups by ammonium cations. On the other hand, both formic acid and acidic ammonium formate can strengthen the electrostatic attraction of C8SCX, causing difficult elution of the alkaloids. Ammonium cations from either the protonated diethylamine or the ionized ammonium formate, were considered as counter ions to effectively mask the electrostatic attraction of C8SCX, to significantly reduce the retention of alkaloids, but improve the resolution. Finally, utilizing two developed SFC methods, i.e., C8SAX with EtOH+ 10 mM acidic ammonium formate in CO2, or C8SCX with EtOH+0.1% diethylamine in CO2, the baseline separation of corynoxeine and isocorynoxeine, rhynchophylline and isorhynchophylline was achieved within 5 min.
Subject(s)
Alkaloids , Ammonium Compounds , Chromatography, Supercritical Fluid , Chromatography, Supercritical Fluid/methods , Carbon Dioxide , Anions/chemistry , Cations/chemistry , Alkaloids/analysisABSTRACT
A new type of hexafluorobutanol (HFB) primary alcohol ethoxylate (AEO)-based supramolecular solvent (SUPRAS) with density higher than water was prepared for the first time. HFB acted as AEO micelle-forming agent and density-regulating agent for SUPRAS formation. The prepared SUPARS was applied as extraction solvent for vortex-assisted direct microextraction of malachite green (MG) and crystal violet (CV) from lake sediment followed by high-performance liquid chromatographic determination. In the present work, SUPRASs prepared from AEO with different carbon chains as the amphiphiles and various coacervation agents were investigated. SUPARS formed from MOA-3 and HFB provided better extraction efficiency in comparison with other SUPRASs. Parameters influencing the extraction recovery of target analytes including the type and volume of AEO, volume of HFB, and vortex time were investigated and optimized. Under optimized conditions, linearity in the range of 2.0-400 µg g-1 for MG and 2.0-500 µg g-1 for CV with a correlation coefficient higher than 0.9947 was obtained. Limits of detection of 0.5 µg g-1 and relative standard deviations in the range of 0.9-5.8% were obtained. Compared to conventional extraction techniques for analysis of analytes in solid samples, the proposed method reduced sample usage and eliminated a primary extraction process by using a toxic organic solvent. The proposed method is simple, fast, and green and can be used for the analysis of target analytes in solid samples.
ABSTRACT
This paper reports on a new strategy for obtaining homogeneous dispersion of grafted quantum dots (QDs) in a photopolymer matrix and their use for the integration of single-photon sources by two-photon polymerization (TPP) with nanoscale precision. The method is based on phase transfer of QDs from organic solvents to an acrylic matrix. The detailed protocol is described, and the corresponding mechanism is investigated and revealed. The phase transfer is done by ligand exchange through the introduction of mono-2-(methacryloyloxy) ethyl succinate (MES) that replaces oleic acid (OA). Infrared (IR) measurements show the replacement of OA on the QD surface by MES after ligand exchange. This allows QDs to move from the hexane phase to the pentaerythritol triacrylate (PETA) phase. The QDs that are homogeneously dispersed in the photopolymer without any clusterization do not show any significant broadening in their photoluminescence spectra even after more than 3 years. The ability of the hybrid photopolymer to create micro- and nanostructures by two-photon polymerization is demonstrated. The homogeneity of emission from 2D and 3D microstructures is confirmed by confocal photoluminescence microscopy. The fabrication and integration of a single-photon source in a spatially controlled manner by TPP is achieved and confirmed by auto-correlation measurements.
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In this paper, an off-line combination method of supercritical fluid extraction and supercritical fluid chromatography was developed for the selective extraction and isolation of diphenylheptanes and flavonoids from Alpinia officinarum Hance. The enrichment of target components was successfully achieved using supercritical fluid extraction with the following conditions (8% ethanol as co-solvent at 45°C and 30 MPa for 30 min). Taking full advantage of the complementarity of supercritical fluid chromatography stationary phases, a two-step preparative supercritical fluid chromatography strategy was constructed. The extract was firstly divided into seven fractions on a Diol column (250 × 20 mm internal diameter, 10 µm) within 8 min by gradient elution increasing from 5% to 20% modifier (methanol) at 55 ml/min and 15 MPa. Then the seven fractions were separated by using a 1-AA or a DEA column (250 × 19 mm internal diameter, 5 µm) at 50 ml/min and 13.5 MPa. This two-step strategy showed superior separation ability for structural analogs. As a result, seven compounds, including four diphenylheptanes and three flavonoids with high purity, were successfully obtained. The developed method is also helpful for the extraction and isolation of other structural analogs of traditional Chinese medicines.
Subject(s)
Alpinia , Chromatography, Supercritical Fluid , Chromatography, Supercritical Fluid/methods , Alpinia/chemistry , Flavonoids , Solvents/chemistry , Methanol/chemistryABSTRACT
Abundant chemical components are key to ensure the evaluation accuracy of fingerprint analysis of traditional Chinese medicines (TCMs). A two-step extraction method combining supercritical fluid extraction (SFE) and water ultrasonic extraction was established for the quality evaluation of Perilla frutescens (L.) Britt. Weakly polar components were extracted under optimal SFE conditions (15% co-solvent (EtOH : n-hexane = 1 : 14, (v/v)), 40 °C, 250 bar, and 30 min), and polar components were subsequently extracted by an ultrasonic step (100% water as solvent, 40 °C, and 45 min). Then, HPLC methods were established, which were validated to be accurate, stable, and reliable. In this work, 25 batches of samples were evaluated and the data were analysed by similarity analysis (SA) and hierarchical cluster analysis (HCA). The similarity values of SFE extracts and aqueous extracts were respectively 0.616-0.999, and 0.252-0.997, proving the importance of the extraction method for the accuracy of the subsequent fingerprint analysis results. For the HCA, 25 samples were divided into two categories (leaves and stems), among which four batches of leaves with less similarity were considered as stems, indicating that quality differences of P. frutescens depending on medicinal parts and origin exist. The two-step extraction method developed in this work has been proved to be suitable for the quality evaluation of TCMs with complex compositions.
Subject(s)
Perilla frutescens , Perilla frutescens/chemistry , Chromatography, High Pressure Liquid/methods , Plant Extracts/analysis , Plant Extracts/chemistry , Solvents/chemistry , WaterABSTRACT
The separation of structural analogues in natural products has always been one of the challenges in separation science, where supercritical fluid chromatography (SFC) with chiral stationary phases (CSPs) is an unconventional but potential solution. In this study, a preparative two-dimensional chiral SFC (2D cSFC) method that was established with two kinds of CSPs was applied in the isolation of the aliphatic acid derivatives in Piper kadsura (P. kadsura). The RPLC unseparated peaks of two samples A and B of P. kadsura were evenly scattered on the CSP-1 column while they clustered into two groups on the CSP-2 column by SFC. There was impressively complementary selectivity between CSP-1 and CSP-2, which were used for construction of 2D cSFC. The first dimension (1D) separation with CSP-1 fractionated the sample A into six parts by a heart-cutting method and the sample B into nine parts for a comprehensive 2D analysis; then 29 and 71 peaks were respectively found in these parts in the second dimension (2D) separation with CSP-2. Further through 2D preparative separation, 19 high purity components were obtained, and the chemical structures of two of them were confirmed, including a novel unsaturated aliphatic acid compound (8Z,10Z)-12-methoxyheptadeca-8,10-dienoic acid and a known octadecadienoic acid lactone Lactariolide. The 2D cSFC method presented the superiority of separating the achiral compounds of complex samples.
Subject(s)
Chromatography, Supercritical Fluid/methods , Drugs, Chinese Herbal/chemistry , Fatty Acids/isolation & purification , Piper/chemistry , Chromatography, High Pressure Liquid , Fatty Acids/analysis , Fatty Acids/chemistry , StereoisomerismABSTRACT
The aims of the study were to assess the contribution of resilience, coping style, and COVID-19 stress on the quality of life (QOL) in frontline health care workers (HCWs). The study was a cross-sectional surveyperformed among 309 HCWs in a tertiaryhospital during the outbreak of COVID-19 in China. Data were collected through an anonymous, self-rated questionnaire, including demographic data, a 10-item COVID-19 stress questionnaire, Generic QOL Inventory-74, Connor-Davidson Resilience Scale, and the Simplified Coping Style Questionnaire. Hierarchical regression was used to analyse the relationship between the study variables and the QOL. Among the 309 participants, resilience and active coping were positively correlated with the QOL (P<0.001), whereas, working in confirmed case wards, COVID-19 stress, and passive coping were negatively correlated with the QOL (P<0.001). Resilience and the active coping were negatively correlated with COVID-19 stress (P<0.001). Resilience, coping style,and COVID-19 stressaccounted for 32%, 13%, and 8% of the variance in predicting the Global QOL, respectively. In conclusion, working in confirmed COVID-19 case wards and COVID-19 stress impaired the QOL in HCWs. Psychological intervention to improve the resilience and coping style, and reduce COVID-19 stress are important in improving the QOL and mental health of HCWs.
Subject(s)
COVID-19 , Resilience, Psychological , Adaptation, Psychological , COVID-19/epidemiology , Cross-Sectional Studies , Health Personnel/psychology , Humans , Quality of Life , SARS-CoV-2ABSTRACT
The integration of nanoparticles (NPs) into photonic devices and plasmonic sensors requires selective patterning of these NPs with fine control of their size, shape, and spatial positioning. In this article, we report on a general strategy to pattern different types of NPs. This strategy involves the functionalization of photopolymers before their patterning by two-photon laser writing to fabricate micro- and nanostructures that selectively attract colloidal NPs with suitable ligands, allowing their precise immobilization and organization even within complex 3D structures. Monolayers of NPs without aggregations are obtained and the surface density of NPs on the polymer surface can be controlled by changing either the time of immersion in the colloidal solution or the type of amine molecule chemically grafted on the polymer surface. Different types of NPs (gold, silver, polystyrene, iron oxide, colloidal quantum dots, and nanodiamonds) of different sizes are introduced showing a potential toward nanophotonic applications. To validate the great potential of our method, we successfully demonstrate the integration of quantum dots within a gold nanocube with high spatial resolution and nanometer precision. The promise of this hybrid nanosource of light (plasmonic/polymer/QDs) as optical nanoswitch is illustrated through photoluminescence measurements under polarized exciting light.
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In this work, a new generation of hydrophobic deep eutectic solvents (DESs) was prepared using eugenol (as hydrogen bond donor) and benzyltriethylammonium bromide, benzyltributylammonium bromide, benzyltriethylammonium chloride and benzyltributylammonium chloride (as hydrogen bond acceptor) in different molar ratios. These DESs were applied to vortex-assisted dispersive liquid-liquid microextraction of Sudan dyes from food samples, followed by high-performance liquid chromatographic determination. The influencing parameters, including the type of DES, amount of DES, extraction time, solution pH and salt addition, were investigated and optimized. Under the optimized conditions, a linear range of 2-1000 ng mL-1 with determination coefficients of <0.999 was obtained. Limits of detection and limits of quantification were in the range of 0.5 to 1 ng mL-1 and 2 to 3 ng mL-1, respectively. The proposed method was successfully used in the determination of Sudan dyes in chili sauce, chili powder and ketchup, and satisfactory recoveries of between 89.9 and 119.3% were obtained, with relative standard deviations in the range of 0.1-6.8%. The proposed method is simple, green and efficient, and can be applied to determine Sudan dyes in complex matrices.
Subject(s)
Coloring Agents/isolation & purification , Food Analysis/methods , Liquid Phase Microextraction/methods , Solvents/chemistry , Chromatography, High Pressure Liquid/methods , Hydrophobic and Hydrophilic Interactions , Limit of Detection , Reference Standards , Spectroscopy, Fourier Transform InfraredABSTRACT
BACKGROUND: The pandemic of coronavirus disease (Covid-19) seriously impacts the health and well-being of all of us. AIMS: We aim to assess the psychological impact of Covid-19 on frontline health care workers (HCWs), including anxiety, depression and stress of threat of the disease. METHOD: The study was a cross-sectional survey among the frontline HCWs in a hospital at Jinan, China. Data were collected through an anonymous, self-rated questionnaire, including basic demographic data, a 10-item Covid-19 stress questionnaire, the Self-Rating Anxiety Scale (SAS) and the Self-Rating Depression Scale (SDS). The risk and rate of anxiety, depression and stress of Covid-19 were estimated. RESULTS: Among the 309 participants, there were 88 (28.5%) with anxiety and 172 (56.0%) with depression. Multivariate logistic regression analyses showed that age ⩽ 30 years, age > 30 to 45 years, working in confirmed case isolation wards, and worrying about disinfection measures being not sufficient were independently associated with anxiety with an odds ratio (95% confidence interval, CI) of 4.4 (1.6-12.2), 3.1 (1.1-8.8), 2.3 (1.4-4.0) and 2.5 (1.5-4.3), respectively; age ⩽ 30 years, age > 30 to 45 years, nurse and worrying about disinfection measure being not sufficient were independently associated with depression with an odds ratio (95% CI) of 3.8 (1.8-7.8), 2.7 (1.3-5.7), 2.5 (1.1-5.6) and 2.1 (1.3-3.5), respectively. CONCLUSIONS: A high prevalence of anxiety and depression was found among frontline HCWs during the COVID-19 outbreak. More psychological care should be given to young staffs and nurses. Measures to prevent professional exposure is important for HCWs' physical and mental health.
Subject(s)
COVID-19 , Population Health , Adult , Anxiety/epidemiology , Cross-Sectional Studies , Depression/epidemiology , Disease Outbreaks , Health Personnel , Humans , Middle Aged , SARS-CoV-2ABSTRACT
Salvia miltiorrhiza injection (SMI) is a classical traditional Chinese medicine, which plays an active role in the treatment of many diseases such as promoting blood circulation, removing blood stasis, reducing inflammatory reaction, and improving acute lung injury (ALI). Previous studies have shown that matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are involved in the pathophysiological process of ALI. However, the relationship between SMI and MMPs/TIMPs remains unclear. In this study, Wistar rats were randomly divided into control group (NC), Salvia miltiorrhiza group (SM), lipopolysaccharide group (LPS), and Salvia miltiorrhiza treatment group (Tsm). The four groups were subdivided into four time points (2, 6, 12, and 24 hours), and specimens were collected after animal sacrifice at each time point. Serum TNF-α and IL-6 levels were detected by ELISA. The degree of lung injury was determined by lung tissue hematoxylin-eosin staining, lung wet/dry weight (W/D) ratio, and lung permeability index. The changes in lung MMPs/TIMPs protein and mRNA were detected by Western blot and real-time quantitative PCR. The results showed that rats injected with LPS experience acute lung injury, and the ratio of MMPs/TIMPs in lung tissues increased gradually with time. In the Tsm group, the ratio of MMPs/TIMPs decreased gradually, and likewise, the balance was gradually restored, while indicators related to lung injury were gradually declined. These data suggest that SMI alleviates LPS-induced acute lung injury; this protective effect may be related to regulation of the balance of MMPs/TIMPs ratio.
ABSTRACT
Hybrid plasmonic nano-emitters based on the combination of quantum dot emitters (QD) and plasmonic nanoantennas open up new perspectives in the control of light. However, precise positioning of any active medium at the nanoscale constitutes a challenge. Here, we report on the optimal overlap of antenna's near-field and active medium whose spatial distribution is controlled via a plasmon-triggered 2-photon polymerization of a photosensitive formulation containing QDs. Au nanoparticles of various geometries are considered. The response of these hybrid nano-emitters is shown to be highly sensitive to the light polarization. Different light emission states are evidenced by photoluminescence measurements. These states correspond to polarization-sensitive nanoscale overlap between the exciting local field and the active medium distribution. The decrease of the QD concentration within the monomer formulation allows trapping of a single quantum dot in the vicinity of the Au particle. The latter objects show polarization-dependent switching in the single-photon regime.