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The zeolitic imidazolate frameworks (ZIFs) are chemically and thermally stable microporous materials that are being considered as ideal supports for the uniform encapsulation of noble metal nanoparticles. Our theoretical investigations started from the adsorption of the molecular precursor Au(CO)Cl in both ZIF-8 and ZIF-90; surprisingly, pore-B, with the diameter less than 2.2 A in the two ZIFs, dramatically expanded as an energetically most favorable site for the location of Au(CO)Cl, whereas the well-known pore-A, with a diameter of about 3.5 A, is less favorable. Then, ab initio molecular dynamics simulations showed that the confined Aun cluster has a transition from two-dimensional to three-dimensional structures when n is larger than 12 in both ZIFs. Interestingly, the aldehyde groups in ZIF-90 were computed to be the main binding sites for Au clusters, whereas the imidazole rings were identified as the binding sites in ZIF-8. Compared to ZIF-90, the binding of Au clusters in ZIF-8 was stronger, acco...

The content of neuron specific enolase (NSE) in serum is considered to be an essential indicator of small cell lung cancer (SCLC). Here, a novel label-free electrochemical immunoassay for the detection of NSE based on the three dimensionally macroporous reduced graphene oxide/polyaniline (3DM rGO/PANI) film has been proposed. The 3DM rGO/PANI film was constructed by electrochemical co-deposition of GO and aniline into the interspaces of a sacrificial silica opal template modified Au slice. During the co-deposition, GO was successfully reduced by aniline and PANI could be deposited on the surfaces of rGO sheets. The ratio of rGO and PANI in the composite was also optimized to achieve the maximum electrochemical performance. The 3DM rGO/PANI composite provided larger specific surface area for the antibody immobilization, exhibited enhanced conductivity for electron transfer, and more important was that PANI acted as the electroactive probe for indicating the NSE concentration. Under the optimal conditions, a linear current response of PANI to NSE concentration was obtained over 0.5 pg mL-1-10.0 ng mL-1 with a detection limit of 0.1 pg mL-1. Moreover, the immunosensor showed excellent selectivity, good stability, satisfactory reproducibility and regeneration, and was employed to detect NSE in clinical serum specimens.

Background and Objectives: The relationship between omega-3 index and type 2 diabetes (T2D) is not well established. It is unclear if the change of omega-3 index will affect T2D. Aiming of the present systematic review was to elucidate the correlation between omega-3 index and T2D. Methods and Study Design: A comprehensive search on PubMed, EMBASE and Web of Science (from 1948 to May 2021) was conducted. The overall effect size (standard mean difference) was combined using a random-effect model. Results: Eight eligible case-control studies were identified, and there were 1,357 patients with T2D and 1,616 non-diabetic controls. The result showed that the omega-3 index was significantly lower in diabetic cases than that in controls (SMD= -1.31; 95% confidence interval (CI): -1.40, -1.22), but with significant heterogeneity (I2 = 99.0%). In subgroup analysis based on race, a negative correlation was found in Asians (SMD = ˗1.71; 95% CI: -1.82, -1.60), and heterogeneity was substantially decreased (I2=0). Conclusions: omega-3 index is negatively correlated with T2D, which indicated that increased dietary intake of omega-3 fatty acids might have beneficial on T2D prevention.

The micro-morphology of catalyst played an important role in the selective catalytic reduction of nitrogen oxide. For the first time, this work investigated the relationship among catalytic activity, catalyst–catalyst distance, and catalyst–reductant distance. Three metal–organic frameworks with different morphologies were applied in the catalysis. When catalyst–catalyst distance was decreased from 3.436 to 2.890 A, the activity was increased from 59.5 to 92.3% at 250 °C. Even without ammonia reductant, when catalyst–reductant distance was decreased from 3.033 to 2.620 A, the activity was increased from 7.5 to 78.1% at 350 °C. In this case, organic/carbon played as the reductant. Moreover, the relationship successfully predicted the activity of a catalyst with a known catalyst–reductant​ distance. A shorter catalyst–catalyst and catalyst–reductant​ distances facilitated electron and material transfers between reductant and nitric oxide, thus increasing the activity. After all, main results of this work helped to understand the interaction on interface between catalyst and reductant, which was in favor of catalyst design and application.

Citrus polymethoxyflavones (PMFs) have been of increasing interest due to their extensive biological activities. In the present study, a total of eight PMFs were isolated from the peel of Citrus reticulata 'Chachi' (CRC). They were individually identified as 5-hydroxy-6,7,8,4'-tetramethoxyflavone (1), 5,6,7,3',4'-pentamethoxyflavanone (2), 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone (3), 3,5,6,7,8,3',4'- heptamethoxyflavone (4), 5,6,7,8,3',4'-hexamethoxyflavone (5), 5,6,7,8,4'-pentamethoxyflavone (6), 6,7,8,3',4'-pentamethoxyflavanone (7) and 5,6,7,3',4'-pentamethoxyflavone (8) by nuclear magnetic resonance and mass spectroscopic analysis. 6,7,8,3',4'-Pentamethoxyflavanone was isolated from the peel of CRC for the first time. The content of PMFs was firstly quantified in both the peel of CRC and PMF-rich extract by HPLC analysis. Furthermore, the biological activities of PMF compounds were investigated. 3,5,6,7,8,3',4'-Heptamethoxyflavone demonstrated potent sterol regulatory element-binding proteins inhibition activity and 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone exhibited strong antiproliferative activity against tumor cell lines. The isolated PMF compounds could also significantly inhibit NO production and the effect varied mainly depending on the number of methoxy groups.

Ardisiae Japonicae Herba is a well-known traditional Chinese medicine for the treatment of bronchitis conjunctivitis, pneumonia, and trauma. In this work, a high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method was first established for the separation and structural identification of the chemical constituents in Ardisiae Japonicae Herba. A total of 15 compounds including coumarins, flavonoid glycosides, and catechins were identified or tentatively characterized based on their chromatographic behaviors and mass spectral fragmentation and by comparisons with the reference standards. Furthermore, a simple high-performance liquid chromatography with diode array detection method was developed for the simultaneous determination of five major constituents. Results obtained from method validation, including linearity, precision, repeatability, stability, and recovery, showed that the established method was reliable and accurate. Bergenin and quercitrin were found to be the most abundant constituents and could be served as chemical markers for quality control of Ardisiae Japonicae Herba.

The present study was designed to develop and validate a rapid, sensitive, and reliable ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) method for the simultaneous determination of five major active constituents in the traditional Chinese medicinal preparation Xingxiong injection (XXI) in rat plasma, including quercetin 3-O-rutinoside (QCR), kaempferol 3-O-rutinoside (KFR), isorhamnetin 3-O-rutinoside (ISR), bilobalide (BB), and ligustrazine (LGT). The plasma samples were pretreated by protein precipitation with acetonitrile. The chromatographic separation was achieved on a Waters Symmetry C18 analytical column (2.1 mm × 100 mm, 3.5 μm) with a mobile phase of 0.1% aqueous formic acid (A)-acetonitrile (B). Quantitation of the five bioactive constituents was achieved. Naringin was used as the internal standard (IS). All the calibration curves showed good linearity (r > 0.996) over the concentration range, with the lowest limit of quantification (LLOQ) between 2-18 ng·mL-1. The intra- and inter-day accuracy and precision of the analytes were both within acceptable limits. Moreover, satisfactory extraction recoveries (90.92%-104.03%) were obtained by protein precipitation. The validated method was successfully applied to a pharmacokinetic study of XXI in rats after intravenous administration at three doses. The pharmacokinetic parameters of the five compounds varied in a dose-dependent manner within the tested dosage range. The present study was the first report of pharmacokinetic study for XXI.

The thermodynamically stable metal organic framework UiO-66-NH2 has experimentally been demonstrated as an ideal platform to isolate metal clusters within its nanocages; however, the electronic structures and the dynamics of the encapsulated metal clusters are still unclear. Ab initio molecular dynamics simulations combined with density functional theory-based methods were employed to search the stable structures of Pdn@UiO-66-NH2 composites, and their electronic properties were analyzed in detail. We found that the thermodynamics of the composites are highly correlated with charge transfer between the Pdn cluster and the UiO-66-NH2 framework, as well as the deformation energy of the framework. In addition, both ab initio molecular dynamics simulations and density functional theory calculations show that the small Pd clusters can easily diffuse into the tetrahedral cage of UiO-66-NH2 from the octahedral cage through the window connecting these two types of cages, with a small energy barrier.

Deep eutectic solvents (DESs) are emerging as alternatives to conventional ionic liquids and organic solvents due to their unique advantages. In the present study, the tuneability of DESs as tailor-made solvents to efficiently extract polar and non-polar bioactive compounds from Platycladi Cacumen was detailedly investigated. Totally 12 types of choline chloride-, betaine-, and l-proline-based DESs were synthesized for initial screening, and extraction conditions was optimized by single-factor experiment. Experiments with different DESs and principal components analysis demonstrated that the extractability of both flavonoid glycosides and aglycones was greater with certain designed DESs than conventional solvents. In addition, the water content in DESs led to significantly different extraction yields of flavonoid compounds. The target compounds were recovered from DESs by macroporous resin LX-38 with a satisfactory yield between 77.44% and 98.92%. The knowledge acquired in this study could contribute to further DES application in extraction of bioactive compounds from natural sources.

A new compound, methylbergenin (1), was isolated from the whole plants of Ardisia japonica (Thunb.) Bl. (Myrsinaceae), along with eight known compounds: demethoxybergenin (2), bergenin (3), afzelin (4), quercitrin (5), bauerenol (6), bauerenone (7), α-spinasterol (8) and chondrillasterone (9). Compounds 1, 7 and 9 were isolated from A. japonica for the first time. The structure of compound 1 was determined on the basis of NMR (1D and 2D) and mass spectroscopic analysis. The absolute configuration of 1 was assessed by single-crystal X-ray diffraction. Compounds 1, 4, 5, 7 and 9 showed potential inhibitory effects against nitric oxide production in LPS stimulated RAW 264.7 murine macrophages. In addition, Compounds 7 and 9 exhibited cytotoxicity against A549 and HepG-2 cells.

Citri Reticulatae Pericarpium, mainly including the pericarp of Citrus reticulata Blanco and the pericarp of Citrus reticulata 'Chachi', has been consumed daily as food and dietary supplement for centuries. In this study, GC-MS based metabolomics was employed to compare comprehensively the volatile constituents in Citrus reticulata Blanco and Citrus reticulata 'Chachi'. Principal component analysis and orthogonal partial least squares discrimination analysis indicated that samples could be distinguished effectively from one another. Fifteen metabolites were finally identified for use as chemical markers in discrimination of Citri Reticulatae Pericarpium samples. The antimicrobial activity against Gram-negative and Gram-positive bacteria of the volatile oil from Citrus reticulata Blanco and Citrus reticulata 'Chachi' was investigated preliminarily.

Phosphate is one of the main contaminations in water, so an effective method of decreasing or removing phosphate is needed. The main purpose of this paper is to synthesize CaFe-LDHs and MgFe-LDHs from the mixture of calcined dolomite and ferric chloride to remove orthophosphate and pyrophosphate. The study showed that removal of orthophosphate was attributed to the precipitation by Ca2+ and adsorption by MgFe-LDHs, where the former played a main role. As for pyrophosphate, it was mainly removed by precipitation at the initial pyrophosphate concentration ranging from 3.228 to 17.04 mmol/L. When the initial concentrations became relatively higher, the removal efficiency of pyrophosphate decreased because the complexation effects by Fe3+, Ca2+ and Mg2+ took place.

A growing number of studies have demonstrated the role of quantitative electroencephalography in assessing brain function in neuro-intensive care units. Still, few studies have examined patients with large hemisphere infarction. Thirty patients with large hemisphere infarction were included in this preliminary study, and the patients were divided into the death group (twelve patients) and survival group (eighteen patients). Electroencephalography monitored the patients, and a computerized tomography inspection was performed. The quantitative electroencephalography of the alpha-beta/delta-theta ratio change index was calculated and used to predict the prognosis of early large hemisphere infarction patients. The relationship between three months modified Rankin Scale, and alpha-beta/delta-theta ratio change index was analyzed. The death group had negative changes for alpha-beta/delta-theta ratio change index (-0.0140 ± 0.0193), while there was an opposite trend in the survival group, the median is 0.004 (-0.0067, 0.0137). The death group’s brain function decreased more severely and rapidly than the survival group (P = 0.004). The highest diagnostic value (AUC value 0.815, P < 0.001) was observed when the alpha-beta/delta-theta ratio change index dropped and exceeded -0.008. The area under the GCS curve was 0.674, but its predictive ability was low (P = 0.094). The correlation analysis result showed that the 3-month modified Rankin Scale was negatively correlated with the alpha-beta/delta-theta ratio change index (r = -0.489, P = 0.006). The alpha-beta/delta-theta ratio change index is considered an indicator for predicting the prognosis of large hemisphere infarction. Therefore, the alpha-beta/delta-theta ratio change index may be a reliable quantitative EEG parameter that predicts the early prognosis of patients with acute large hemispheric infarction.

Selection of suitable labeled constituents is vital for the quality standardization of herbal medicines (HMs). However, discovery of labeled constituents that can account for the whole efficacy of original HMs is a challenging issue. Taking tanshinones extract (TE) as an example, a strategy to establish reasonable quality control method using effective compounds combination (ECC) as labeled constituents was proposed. The strategy consists of three core steps, including chemical profiling of TE, discovery and in vivo process research of ECC, and quality standardization based on ECC. Using this strategy, a combination of four tanshinones (tanshinones IIA, cryptotanshinone, tanshinone I and dihydrotanshinone I), which was as effective as TE in cell models and in a rat model of myocardial ischemia-reperfusion, was identified as ECC in TE. Furthermore, quality standardization of TE was established based on proposed ECC using single standard for determination of multiple components (SSDMC) method. In conclusion, the presently developed ECC-based approach not only offers new insight into the understanding of the holistic effects of HMs, but also provides efficacy-associated labeled constituents for quality control of botanicals.

Large amount of phosphorous is the main factor for eutrophication. Removal of orthophosphate and pyrophosphate with CaFe-Cl-LDHs was explored in the paper. And the aim of this paper was to investigate the different mechanisms of orthophosphate and pyrophosphate removal by CaFe-Cl-LDHs. The results displayed that the removal process was precipitation-dissolution between Ca2+ and orthophosphate or pyrophosphate, which was fitted with the pseudo-second-order equation well; when Ca2+ was not enough, pyrophosphate had a competitive advantage over orthophosphate; as the concentration of pyrophosphate increased, precipitate was formed by Ca2+ and . The simultaneous removal of orthophosphate and pyrophosphate on CaFe-Cl-LDHs was also evaluated to provide information for the treatment of domestic and industrial wastewaters.

Deep eutectic solvents (DESs) are emerging as green and sustainable solvents for efficient extraction of bioactive compounds or drugs. This work aimed to comprehensively evaluate the potential and effectiveness of DESs for extraction of different types of natural compounds from biomass. Five Chinese herbal medicines including Berberidis Radix, Epimedii Folium, Notoginseng Radix et Rhizoma, Rhei Rhizoma et Radix, and Salviae Miltiorrhizae Radix et Rhizoma were selected to assess the efficiency of DESs on extraction of alkaloids, flavonoids, saponins, anthraquinones, and phenolic acids, respectively. Totally 43 types of choline chloride-, betaine-, and l-proline-based DESs with different polarity, viscosity, composition, and solubilization abilities were tailored to test their extraction efficiency, and the operation conditions were statistically optimized using response surface methodology to produce the most efficient process. In this work, DES solvents were first introduced to extract alkaloids and anthr...

A new method involving a coupling reaction and vacuum distillation (RVD) was introduced to prepare the β-CD cross-linking polymeric adsorbent (PCDRVD). The preparation conditions, including the molar ratio of cross-linking agent and β-CD, dosage of the solvent, reaction time, and vacuum distillation temperature and time, were investigated in detail. Compared with a product prepared at normal pressure, PCDRVD possessed a lower content of β-CD, a higher content of carboxyl groups, a lower adsorption selectivity, and a higher efficiency as well as adsorption capacity to remove dyes methylene blue (MB), and Rhodamine B (RhB), methyl orange (MO). The PCDRVD was characterised by FT-IR, TG, and SEM, and was employed for the adsorption of MB and RhB from an aqueous solution. Results showed that the adsorption quantity of MB (Qe,MB) was higher than that of Qe,RhB, except in the acidic medium. The equilibrium data followed the Langmuir isotherm model, and the calculated Qm,MB and Qm,RhB were 250.0 mg/g and 231.5 mg/g, respectively. The adsorption kinetics fitted the pseudo-second-order model. It was inferred that PCDRVD exhibited a high adsorption capacity for both dyes due to its more homogeneous polymeric network formed during RVD and the higher content of carboxyl groups. The differences between Qe,MB and Qe,RhB were mainly attributed to the size of MB and RhB.

Key Points Question Which community preventive measures were implemented in a Chinese city to address the coronavirus disease 2019 (COVID-19) pandemic, and were they associated with limited community transmission? Findings This retrospective case series included 7 imported COVID-19 cases and 800 individuals at high risk. After the implementation of community measures, no locally acquired case of COVID-19 with indirect links to confirmed cases was identified in the community. Meaning The findings of this study suggest that the implementation of community containment strategies by a multidisciplinary team may limit the community transmission of COVID-19., This case series study examines measures implemented in a community in China to restrict the spread of coronavirus disease 2019., Importance A new outbreak of pneumonia caused by severe acute respiratory syndrome coronavirus 2 in Wuhan, China, is spreading rapidly around the globe. Limited information on control in community settings is available. Objective To detail measures enacted within a community to prevent the spread of coronavirus disease 2019 (COVID-19) and to evaluate the spread of COVID-19 associated with implementation of the program. Design, Setting, and Participants This case series study details the implementation of prevention measures in a specific community setting among community-dwelling individuals exposed to or at risk of COVID-19 in Haiyu, Shenzhen, China, from January 23 to April 10, 2020. Exposures Community containment strategies for tracking, quarantine, and management were strictly, cooperatively, and effectively implemented by a team that included a general practitioner, a community manager, and public safety bureau officials. Main Outcomes and Measures Number of locally acquired cases with indirect links to confirmed COVID-19 cases. Diagnosis with COVID-19 was confirmed when throat swab samples tested positive for severe acute respiratory syndrome coronavirus 2 on reverse transcription–polymerase chain reaction. Results Approximately 34 686 individuals live in Haiyu, including 2382 residents aged 65 years or older. Seven individuals with COVID-19 acquired outside the community (age, 20-70 years; 3 [42%] women) were moved from quarantine to a hospital for standard isolation treatment. A total of 20 people who were asymptomatic and who had had direct contact with these individuals were closely observed by health care workers at a nearby hotel. Additionally, 800 individuals considered to be at higher risk were moved from quarantine to home isolation for 14 days. There were no locally acquired cases of COVID-19 with indirect links reported in the Haiyu community from the time that the study began on January 23, 2020, to April 10, 2020. Conclusions and Relevance These findings suggest that cooperation among the authorities of multiple sectors allowed for the implementation of preventive measures that were associated with limited community transmission.