Effect of microstructure in mesoporous adsorbents on the adsorption of low concentrations of VOCs: An experimental and simulation study.

This study evaluated the adsorption of five volatile organic compounds (VOCs) on Opoka, precipitated silica, and palygorskite, to elucidate the effect of their pore size on VOCs adsorption. The adsorption capacity of these adsorbents is not only highly correlated with their surface area and pore volume, but also notably improved by the presence of micropores. The variation in adsorption capacity for different VOCs was primarily influenced by their boiling point and polarity. Palygorskite, which had the smallest total pore volume (0.357 cm3/g) but the largest micropore volume (0.043 cm3/g) among the three adsorbents, exhibited the highest adsorption capacity for all tested VOCs. Additionally, the study constructed slit pore models of palygorskite with micropores (0.5 and 1.5 nm) and mesopores (3.0 and 6.0 nm), calculated and discussed the heat of adsorption, concentration distribution, and interaction energy of VOCs adsorbed on different pore models. The results revealed that the adsorption heat, concentration distribution, total interaction energy, and van der Waals energy decrease with increasing pore size. The concentration of VOCs in 0.5 nm pore was nearly three times that in 6.0 nm pore. This work can also provide guidance for further research on using adsorbents with mixed microporous and mesoporous structures to control VOCs.

Identification of an α-Oxoamine Synthase and a One-Pot Two-Step Enzymatic Synthesis of α-Amino Ketones.

Alb29, an α-oxoamine synthase involved in albogrisin biosynthesis in Streptomyces albogriseolus MGR072, was characterized and responsible for the incorporation of l-glutamate to acyl-coenzyme A substrates. Combined with Alb29 and Mgr36 (an acyl-coenzyme A ligase), a one-pot enzymatic system was established to synthesize seven α-amino ketones. When these α-amino ketones were fed into the alb29 knockout strain Δalb29, respectively, the albogrisin analogs with different side chains were observed.

[Effects of Different Rotation Patterns of Oil-Rice on Methane and Nitrous Oxide Emissions in Rice Fields].

A field experiment was carried out to investigate the effects of different rice-rape rotation systems on methane and nitrous oxide emissions, which were measured using the static chamber/gas chromatography method, prediction of their global warming potentials (GWP), and greenhouse gas intensity (GHGI) in paddy fields. The results showed that the average cumulative emissions of CH4from a double cropping paddy field, single season rice field (including middle or late), rape field, and leisure land were 135.25, 55.64, 5.05, and 1.89 kg ·hm-2, respectively. The CH4 emission during the rice season accounted for 91.8%-98.5% of the annual CH4 emission in different rotation years, and the contents of dissolved organic carbon in paddy soil exhibited a significantly positive correlation with CH4 emission. The CH4 emission in conventional late rice paddy was 18.7% higher than that of hybrid late rice paddy (P<0.05). The average cumulative emissions of N2O from double cropping paddy field, single season rice field (including middle or late), rape field, and leisure land were 0.94, 0.64, 1.38, and 0.24 kg ·hm-2, respectively. Out of the total annual N2O emission, 57.2% to 70.2% was from the rape field; 17.8% and 30.6% was due to the winter fallow treatments with previous crop type of double corpping rice and single season rice, respectively. There was no significant difference in N2O emission between hybrid rice and conventional rice paddy fields. The GWP of double cropping rice-winter fallow and double cropping rice-rape was higher than that of rice-rape and rice-winter fallow, and the GWP of CH4 in rice season accounted for 71.2% to 90.9% of the annual GWP of rotation. The highest treatment of GHGI was rice-rice-rape, and the treatment of rice-oil and rice-winter slack was lower. According to the comprehensive environmental and economic benefits, the late hybrid rice-rape patterns should be selected to reduce greenhouse gases in multiple cropping rice fields of South China.

Rice OsHSFA3 Gene Improves Drought Tolerance by Modulating Polyamine Biosynthesis Depending on Abscisic Acid and ROS Levels.

Drought is a serious problem, which causes heavy yield losses for rice. Heat-shock factors (HSFs) had been implicated in tolerance to drought and high temperature. However, there has not been much functional characterization and mechanism clarification in rice. Previously, we found an HSF gene, OsHSFA3, was highly related with drought tolerance after screening from 10,000 different samples. Herein, we cloned the OsHSFA3 from rice and overexpressed it in Arabidopsis thaliana to study its regulatory mechanism of drought tolerance. Phenotypic and physiological assays of the transgenic Arabidopsis lines showed that overexpression of OsHSFA3 confers drought tolerance by reducing water loss and reactive oxygen species (ROS) levels, whereas it increases abscisic acid (ABA) levels. However, enzymatic antioxidants such as activity levels of superoxide dismutase, peroxidase and catalase were not significantly different between wild type and transgenic lines. Instead, we observed a significant increase in polyamine content, which was correlated with increased AtADC1, AtADC2, SPDS1 and SPMS expression levels. In silico and in vivo analyses confirmed that OsHSFA3 is a nuclear-localized gene. In addition, OsHSFA3 can bind to the promoter of AtADC1 and OsADC via a yeast one-hybrid assay. Overall, this study reveals that OsHSFA3 improves drought tolerance in Arabidopsis not only by increasing ABA levels, but also by modulating polyamine levels to maintain ROS homeostasis, therefore it could be a strong candidate to develop drought-tolerant rice cultivars.

Characterization and Nonenzymatic Transformation of Three Types of Alkaloids from Streptomyces albogriseolus MGR072 and Discovery of Inhibitors of Indoleamine 2,3-Dioxygenase.

The known benzonaphthyridine alkaloid, albogrisin A (1), and six new compounds, including two pyrazinone stereoisomers, albogrisin B (2)/B' (2'), together with four 4H-pyrroloquinolinones, two diastereoisomers, albogrisin C (3)/C' (3'), and their methyl esters, albogrisin D (4)/D' (4'), were isolated from mangrove-derived Streptomyces albogriseolus MGR072. 2 and 2' are converted into 1 in acidic aqueous solution but into 3/3' and 4/4' in 0.05% trifluoroacetic acid acetonitrile. 4 and 4' are new indoleamine 2,3-dioxygenase 1 inhibitors.

Evolution of the burden of active hepatitis C virus infection in England from September 2015 to September 2016: a repeated cross-sectional analysis.

OBJECTIVE: To evaluate the impact of treatment with new direct-acting antivirals (DAAs) on the prevalent hepatitis C virus (HCV) population in England. DESIGN: A repeated cross-sectional analysis. SETTING: Four secondary care hospitals in England. PARTICIPANTS: Patients who, in 2015 and/or 2016, had chronic HCV infection and were alive were eligible, regardless of the type of HCV intervention received. OUTCOME MEASURES: Data including intravenous drug use (IVDU) status, HCV genotype, cirrhosis status, HCV treatment history, vital status and treatment outcomes were collected at two time points in 2015 and 2016 using electronic case report forms. RESULTS: There were 1605 and 1355 patients with active chronic HCV in 2015 and 2016, respectively. Between 2015 and 2016, the proportion of patients with current IVDU increased (10.3% vs 14.5%, respectively), while that of patients with cirrhosis (28.2% vs 22.4%) and treatment-experienced patients (31.2% vs 27.1%) decreased. Among patients whose treatment outcome was known by 2016, high cure rates were observed, with an overall sustained virological response rate of 93.2%. From 2015 to 2016, there was a progressive increase in the proportion of treated patients who were non-cirrhotic, with current IVDU and non-liver transplant recipients. CONCLUSIONS: The characteristics of patients with HCV remaining in contact with specialised care evolved with a changing landscape of treatment and related health policy. With increasing access to DAAs in UK, high cure rates were achieved in the study cohort.

Metal-free oxidative radical cascade addition/oxobutylation of unactivated alkenes with acetone towards 3-(3-oxobutyl)indolines.

A direct oxobutylation of N-allyl anilines with acetone was developed under metal-free and acid-free conditions. This reaction tolerates a series of functional groups to provide 3-(3-oxobutyl) functionalized indolines in moderate to good yields.

Metal-free radical cascade chloromethylation of unactivated alkenes: synthesis of polychloro-substituted indolines.

The di- and trichloromethylation of N-allyl anilines was developed under metal-free conditions, leading to a variety of di- and trichloromethylated indolines in moderate to good yields. This procedure used the commercially available chemical feedstocks CH2Cl2, CHCl3 and CCl4 as the di- and trichloromethyl sources.

New C13 lipids from the marine-derived fungus Trichoderma harzianum.

Chemical examination of the fermentation broth of a sponge-associated fungus Trichoderma harzinum HMS-15-3 led to the isolation of four pairs of new C13 lipid enantiomers namely harzianumols A-H (1a-4b). Their structures were elucidated on the basis of extensive spectroscopic (IR, MS, 1D, and 2D NMR) data analysis, including the modified Mosher's method for the assignment of their absolute configurations. The new compounds were evaluated for antihyperlipidemic effects in HepG2 cells.

In vivo metabolism study of xiamenmycin A in mouse plasma by UPLC-QTOF-MS and LC-MS/MS.

Xiamenmycin A is an antifibrotic leading compound with a benzopyran skeleton that is isolated from mangrove-derived Streptomyces xiamenensis. As a promising small molecule for fibrotic diseases, less information is known about its metabolic characteristics in vivo. In this study, the time-course of xiamenmycin A in mouse plasma was investigated by relative quantification. After two types of administration of xiamenmycin A at a single dose of 10 mg/kg, the plasma concentrations were measured quantitatively by LC-MS/MS. The dynamic changes in the xiamenmycin A concentration showed rapid absorption and quick elimination in plasma post-administration. Four metabolites (M1-M4) were identified in blood by UPLC-QTOF-MS, and xiamenmycin B (M3) is the principal metabolite in vivo, as verified by comparison of the authentic standard sample. The structures of other metabolites were identified based on the characteristics of their MS and MS/MS data. The newly identified metabolites are useful for understanding the metabolism of xiamenmycin A in vivo, aiming at the development of an anti-fibrotic drug candidate for the therapeutic treatment of excessive fibrotic diseases.

Effect of traditional Chinese medicine on oligoasthenospermatism: a narrative review.

OBJECTIVE: To summarize the treatment of oligoasthenospermatism (OAS) with Traditional Chinese Medicine (TCM). METHODS: The literature describing OAS treatment with TCM in the past 4 years was searched. Three studies were reviewed, evaluated, and summarized. The etiology and pathogenesis, pattern differentiation, medicine administration, and combination of TCM with Western Medicine were all examined. RESULTS: TCM had an advantage in treating OAS and had fewer adverse events than conventional treatments. CONCLUSION: Although TCM has an advantage in treating OAS and fewer adverse events, the efficacy of TCM and modern medicine on OAS is unsatisfactory.

Hybrid gold-gadolinium nanoclusters for tumor-targeted NIRF/CT/MRI triple-modal imaging in vivo.

Multimodal imaging is highly desirable for accurate diagnosis because it can provide complementary information from each imaging modality. In this study, we prepared hybrid gold-gadolinium nanoclusters (NCs), which are ultrasmall, stable, biocompatible, and suitable for triple-modal NIRF/CT/MRI imaging. Upon intravenously injected, the hybrid NCs are effectively accumulated in tumor tissues and quickly clear by renal excretion, indicating their capacity of tumor targeting and low body residues. Notably, the ultrasmall hybrid NCs would penetrate into the solid tumor for capturing its heterostructure and do not induce potential toxicity in vivo. Hence, the well-defined hybrid gold-gadolinium NCs provide a versatile nanoprobe for cancer targeted imaging and diagnosis in vivo.