Lauinoids A-X: Labdane-type diterpenoids with anti-inflammatory activity from Croton laui.

Croton laui (Euphorbiaceae) is a traditional medicinal plant used by the Li ethnic group in China to treat headaches, stomachaches, and diphtheria. To understand the pharmacological basis of its medicinal use, an extensive investigation of the ethanolic extract of the bark of C. laui was performed. After repeated chromatography, twenty-four undescribed labdane-type diterpenoids, lauinoids A-X (1-24), and five known analogs (25-29) were isolated. Their structures and absolute configurations were established using a combination of spectroscopic analyses, electronic circular dichroism, nuclear magnetic resonance calculations, and single-crystal X-ray diffraction. Among them, compounds 1-3 exhibited an 11(12 â†’ 13)-abeo-16-nor-labdane skeleton, which originated putatively from 9 through a plausible pathway that involves a semipinacol rearrangement process. Compounds 11 and 12 belong to the rare class of 14,15-dinor-labdane diterpenoids. Compounds 18 and 28 exhibited substantial inhibitory effects by suppressing lipopolysaccharide-induced NO production in RAW 264.7 macrophages, with IC50 values of 3.37 ± 0.23 and 5.82 ± 0.28 µM, respectively. This study has greatly expanded the chemical diversity of labdane diterpenoids from C. laui and will guide future research on this ethnomedicinal plant.

Drymariamides A-J, Antiadipogenic Cyclopeptides Incorporating Noncanonical Amino Acids from Drymaria cordata.

Herein, we report an extensive phytochemical study on the whole plant of Drymaria cordata, which led to the isolation of ten new orbitides, named drymariamides A-J (1-10). Compounds 2, 3, and 5 incorporate rare residues of noncanonical amino acids of kynurenine (Kyn) or 3a-hydroxypyrroloindoline (HPI). Their structures with absolute configurations were elucidated by a combination of spectroscopic analysis, advanced Marfey's method, X-ray diffraction, and electronic circular dichroism analysis. Compounds 1-10 exhibited antiadipogenic effects in 3T3-L1 adipocytes, and the most potent compound 7 showed an EC50 value of 1.17 ± 0.19 µM.

Mitochondrial ferritin upregulation reduced oxidative stress and blood-brain-barrier disruption by maintaining cellular iron homeostasis in a neonatal rat model of germinal matrix hemorrhage.

Germinal matrix hemorrhage (GMH) is a devasting neurological disease in premature newborns. After GMH, brain iron overload associated with hemoglobin degradation contributed to oxidative stress, causing disruption of the already vulnerable blood-brain barrier (BBB). Mitochondrial ferritin (FTMT), a novel mitochondrial outer membrane protein, is crucial in maintaining cellular iron homeostasis. We aimed to investigate the effect of FTMT upregulation on oxidative stress and BBB disruption associated with brain iron overload in rats. A total of 222 Sprague-Dawley neonatal rat pups (7 days old) were used to establish a collagenase-induced GMH model and an iron-overload model of intracerebral FeCl2 injection. Deferiprone was administered via gastric lavage 1 h after GMH and given daily until euthanasia. FTMT CRISPR Knockout and adenovirus (Ad)-FTMT were administered intracerebroventricularly 48 h before GMH and FeCl2 injection, respectively. Neurobehavioral tests, immunofluorescence, Western blot, Malondialdehyde measurement, and brain water content were performed to evaluate neurobehavior deficits, oxidative stress, and BBB disruption, respectively. The results demonstrated that brain expressions of iron exporter Ferroportin (FPN) and antioxidant glutathione peroxidase 4 (GPX4) as well as BBB tight junction proteins including Claudin-5 and Zona Occulta (ZO)-1 were found to be decreased at 72 h after GMH. FTMT agonist Deferiprone attenuated oxidative stress and preserved BBB tight junction proteins after GMH. These effects were partially reversed by FTMT CRISPR Knockout. Iron overload by FeCl2 injection resulted in oxidative stress and BBB disruption, which were improved by Ad-FTMT mediated FTMT overexpression. Collectively, FTMT upregulation is neuroprotective against brain injury associated with iron overload. Deferiprone reduced oxidative stress and BBB disruption by maintaining cellular iron homeostasis partially by the upregulating of FTMT after GMH. Deferiprone may be an effective treatment for patients with GMH.

(-)-Epigallocatechin gallate alleviates chronic unpredictable mild stress-induced depressive symptoms in mice by regulating the mTOR autophagy pathway and inhibiting NLRP3 inflammasome activation.

Depression is a global public health issue that is widely studied due to the large number of people it affects and its serious consequences. Clinical studies have shown that regular tea consumption may reduce depression risk. (-)-Epigallocatechin gallate (EGCG), the main tea polyphenol, was observed to alleviate depression, but the underlying mechanism has not been elucidated. In this study, chronic unpredictable mild stress (CUMS) was used to induce depression-like behavior in mice, and behavioral tests, such as sucrose preference test and forced swim test, were performed. Then, ELISA, western blot and QT-PCR tests were used to assess the expression of the key components of the NLRP3 inflammasome and its downstream inflammatory effectors (e.g., IL-1ß, IL-18), autophagy markers (Beclin-1, LC3, P62) and apoptosis markers (Bax, Bcl-2) in mouse brain tissues. Changes in serum lipid levels were also assessed. EGCG alleviated CUMS-induced depression-like behavioral changes in mice, reduced activation of the NLRP3 inflammasome, inhibited the mTOR signaling pathway, restored autophagy levels, reduced apoptosis marker expression and attenuated abnormal changes in blood lipid levels. Our study demonstrates that EGCG exerts antidepressive effects through multiple mechanisms, providing new insight into the pathological mechanism of depression and laying the foundation for the development of new therapeutic measures.

Effect of forchlorfenuron and thidiazuron on kiwifruits' internal qualities, optical properties and their relationship during growth.

Forchlorfenuron (1-(2-chloropyridin-4-yl)-3-phenylurea, CPPU) and thidiazuron (N-Phenyl-N'-1,2,3-thiadiazol-5-ylurea, TDZ) are two widely used plant growth regulators in kiwifruit cultivation. They can promote fruit size, but it is unclear whether they have same effect on internal qualities, optical properties and cell structure of kiwifruit, and whether the kiwifruits treated with CPPU and TDZ can be identified based on optical properties. To answer these questions, the kiwifruits treated with 20 mg/L CPPU and 2 mg/L TDZ solutions were used as samples, and the untreated kiwifruits were used as control to investigate the optical properties (absorption coefficient µa and reduced scattering coefficient µs'), internal qualities (soluble solids content (SSC), firmness and moisture content) and microstructure of pulp tissue during the growth. Moreover, the relationship between the optical properties and internal qualities were analyzed, and the potential for identifying the kiwifruits treated with CPPU and TDZ based on optical properties was evaluated. The results showed that CPPU and TDZ increased the SSC and reduced the firmness of kiwifruits, but had some different effects on the moisture content and cell size. CPPU and TDZ did not influence the change trend of µa and µs' with wavelength, but affected their values and the relationship with internal qualities. In general, the mean µa of the kiwifruits treated with CPPU and with TDZ was the largest and the smallest at the absorption peaks (980 nm, 1190 nm and 1420 nm), respectively. The linear discriminant analysis modeling results showed that the spectra of µa with µs' had greater potential in identifying the kiwifruits treated with CPPU/TDZ with accuracy of 75.76 %.

Optimized Extraction, Identification and Anti-Biofilm Action of Wu Wei Zi (Fructus Schisandrae Chinensis) Extracts against Vibrio parahaemolyticus.

The pathogenicity of foodborne Vibrio parahaemolyticus is a major concern for global public health. This study aimed to optimize the liquid-solid extraction of Wu Wei Zi extracts (WWZE) against Vibrio parahaemolyticus, identify its main components, and investigate the anti-biofilm action. The extraction conditions optimized by the single-factor test and response surface methodology were ethanol concentration of 69%, temperature at 91 °C, time of 143 min, and liquid-solid ratio of 20:1 mL/g. After high performance liquid chromatography (HPLC) analysis, it was found that the main active ingredients of WWZE were schisandrol A, schisandrol B, schisantherin A, schisanhenol, and schisandrin A-C. The minimum inhibitory concentration (MIC) of WWZE, schisantherin A, and schisandrol B measured by broth microdilution assay was 1.25, 0.625, and 1.25 mg/mL, respectively, while the MIC of the other five compounds was higher than 2.5 mg/mL, indicating that schisantherin A and schizandrol B were the main antibacterial components of WWZE. Crystal violet, Coomassie brilliant blue, Congo red plate, spectrophotometry, and Cell Counting Kit-8 (CCK-8) assays were used to evaluate the effect of WWZE on the biofilm of V. parahaemolyticus. The results showed that WWZE could exert its dose-dependent potential to effectively inhibit the formation of V. parahaemolyticus biofilm and clear mature biofilm by significantly destroying the cell membrane integrity of V. parahaemolyticus, inhibiting the synthesis of intercellular polysaccharide adhesin (PIA), extracellular DNA secretion, and reducing the metabolic activity of biofilm. This study reported for the first time the favorable anti-biofilm effect of WWZE against V. parahaemolyticus, which provides a basis for deepening the application of WWZE in the preservation of aquatic products.

How Does Environmental Information Disclosure Affect Public Health? Evidence from the New Ambient Air Quality Standards.

Using a quasi-natural experiment of the implementation of the new Ambient Air Quality Standards in China, this paper assessed the impact of environmental information disclosure on public health. Our empirical results showed that environmental information disclosure (EID) largely improved both physical health and mental health. Moreover, we further investigated the air pollution channel, and the empirical results showed that EID could reduce the concentration of PM2.5, which could cause an increase in public health as the concentration of PM2.5 decreases. In addition, in terms of individual characteristics, the impact of EID was larger for men, people living in the countryside and people older than 60. In terms of the heterogeneity of cities, the impact of EID was larger in cities with higher public environmental concerns, and the impact of EID was more pronounced in core cities. For regional heterogeneity, the impact of EID on physical health was more pronounced in more developed regions, whereas the impact EID on mental health was higher in less developed regions.

Antagonistic activity and mode of action of trypacidin from marine-derived Aspergillus fumigatus against Vibrio parahaemolyticus.

This study aimed to investigate the antagonistic activity and mode of action of trypacidin from marine-derived Aspergillus fumigatus against Vibrio parahaemolyticus. Results indicated that the minimal inhibitory concentration and minimal bactericidal concentration of trypacidin against V. parahaemolyticus were 31.25 and 62.5 µg/mL, respectively, which was better than that of streptomycin sulfate. Trypacidin remarkably inhibited the growth of V. parahaemolyticus and had a strong destructive effect on cell wall permeability and integrity, cell membrane permeability, and morphological alterations. Its potential as an antibacterial agent for aquatic products must be further explored.

Antibacterial Molecules from Marine Microorganisms against Aquatic Pathogens: A Concise Review.

Antibiotic resistance and residues in aquaculture are a growing concern worldwide and consequently identifying favorable antibacterial compounds against aquatic pathogenic bacteria are gained more attention. Active compounds derived from marine microorganisms have shown great promise in this area. This review is aimed to make a comprehensive survey of anti-aquatic pathogenic bacterial compounds that were produced by marine microorganisms. A total of 79 compounds have been reported, covering literature from 1997 to 2021. The compounds are included in different structural classes such as polyketides, terpenoids, nitrogen compounds and others, and some of them present the potential to be developed into agents for the treatment of aquatic pathogenic bacteria.

Kindness is rewarded! The impact of corporate social responsibility on Chinese market reactions to the COVID-19 pandemic.

This study takes the COVID-19 outbreak as a quasi-natural experiment to investigate whether corporate social responsibility (CSR) performance can help firms mitigate drops in their share prices. The results show that CSR ratings are positively associated with cumulative abnormal return (CAR) during the COVID-19 outbreaks periods. Further, the positive role of CSR is more significant for non-state-owned enterprises (non-SOE) and those located in regions with lower levels of marketization.

Bioassay-guided isolation and characterization of antibacterial compound from Aspergillus fumigatus HX-1 associated with Clam.

This study aimed to identify a symbiotic fungus strain HX-1 with anti-Vibrio harveyi activity and isolate and identify the active compound. The HX-1 strain was identified as Aspergillus fumigatus according to the morphological characteristics and internal transcribed spacer (ITS) sequence analysis. The compound was isolated from the fermentation product of HX-1 strain through ethyl acetate extraction, silica gel and Sephadex LH-20 column chromatography, and semi-preparative HPLC techniques using an antibacterial-guided fractionation method. According to its physicochemical properties and spectral characteristics, the compound was identified as trypacidin having the same anti-V. harveyi activity as streptomycin sulfate, with the minimum inhibitory concentration of 31.25 µg/mL.

Structurally diverse steroids with nitric oxide inhibitory activities from Aglaia lawii leaves.

Eleven previously uncharacterized steroids, along with three analogs were isolated from Aglaia lawii leaves. Their structures were definitely characterized by the methods of NMR, MS, IR, ECD and X-ray crystallography study. Among these unreported compounds, 3-epi-dyscusin C, 3-epi-lansisterone E and (Z)-2α-hydroxyaglawone were C-21 pregnane steroids incorporating a highly oxygenated ring A, while others were Δ5-3ß-hydroxy-7-ketosteroids bearing different ring D and C-17 aliphatic chains. All isolates were evaluated for nitric oxide (NO) inhibitory activities. 3-Epi-dyscusin C, 3-epi-lansisterone E, (Z)-2α-hydroxyaglawone and 17(20)E-dyscusin B showed significant anti-inflammatory activities with IC50 values of NO inhibition less than 10 µM (in the range from 4.47 ± 0.36 to 7.67 ± 0.46 µM).

Four new steroids from the leaves and twigs of Dysoxylum pallens and their cytotoxic activities.

Four previously undescribed steroids, identified as (3S,7S,8S,9S,10R,13S,14S,16S,17R,20S)-7α-methoxy-ergosta-5,24(28)-dien-3ß,16ß,20-triol (1), ergosta-5,24(28)-dien-3ß,7α,16ß-triol (2), ergosta-5,25-dien-3ß,7α,16ß,20-tetrol (3) and 7α,16ß,24α-trihydroxy-varninasterol (4), as well as five known analogues (5-9), were isolated from the leaves and twigs of Dysoxylum pallens Hiern (Meliaceae). Their structures were elucidated based on extensive spectroscopic analysis such as HR-ESI-MS, 1D and 2D NMR, UV, and IR. The absolute configuration of compound 1 was determined by X-ray diffraction analysis. Selected compounds were evaluated for their cytotoxic activities. Compounds 1, 2, and 8 exhibited moderate cytotoxic activity against HL-60, Hela, and HepG2 tumor cell lines with IC50 ranged from 11.09 to 17.51 µM.

Development of a high-resolution emission inventory of agricultural machinery with a novel methodology: A case study for Yangtze River Delta region.

Recent increased use of agricultural machines elevated the atmospheric pollutant emissions in the Yangtze River Delta (YRD) region in eastern China. Given the potentially large environmental and health impacts in busy seasons with enhanced machinery usage, it is important to accurately estimate the magnitude, spatial and temporal distributions of the emissions. We developed a novel method to estimate the real-world in-use agricultural machinery emissions, by combining satellite data, land and soil information, and in-house investigation. The machinery usage was determined based on the spatial distribution, growing and rotation pattern of the crops. The varied requirement of machinery power by heterogeneous soil texture, which was ignored in the previous studies, was considered in our methodology. The spatiotemporal pattern of machinery usage was determined based on the explored quantitative correlation between the local agricultural activity duration and the geographic location of the activity. A "grid-based" (30 × 30 m) inventory with daily emissions was then obtained, achieving significant improvement on spatial and temporal resolution. It substantially diminished the bias of previous inventories based on the machinery population or power installation census data. The emissions of NOX, PM2.5, CO and THC were estimated at 36300, 2000, 36900 and 8430 metric tons in YRD, with the majority contribution from Anhui and Jiangsu. Ten cities locating in northern and central Anhui and Jiangsu contributed the largest machinery emissions, accounting for 60% of the total emissions in YRD. Harvesting was found to have the largest emissions, followed by tilling and planting. Regarding the crops, the emissions from wheat and rice related machinery usage were the largest. In the busy seasons (spring and autumn), larger daily NOX and PM2.5 emissions were found from machinery than on-road vehicles in 42% of counties in Anhui and Jiangsu, highlighting the necessity of careful strategy making on controls of priority emission source.

Design of an InP/ZnO core-shell nanocone array solar cell with efficient broadband light absorption enhancement.

We design a standing semiconductor-dielectric core-shell nanocone array (CSNCA) that can not only concentrate the incident light into the structure, but also confine most of the concentrated light to the semiconductor (indium phosphide) core region, which remarkably enhances the light absorption of the more material-saving semiconductor core. We find guided resonance features along the radial and FP-resonant features along the axial direction by analyzing the electric field patterns at the absorption spectrum peaks. The CSNCA can support multiple higher-order HE modes, in comparison to the bare nanocone array (BNCA). Results based on detailed balance analysis demonstrate that the core-shell design gives rise to higher short-circuit current and open-circuit voltage, and thus higher power conversion efficiency. Detailed research is focused on the 1 µm high CSNCAs, and a remarkable power conversion efficiency enhancement (42.2%) is gained compared with the BNCAs.

Aspidoptoids A-D: Four New Diterpenoids from Aspidopterys obcordata Vine.

Four new diterpenoids, named aspidoptoids A-D (1-4), together with two known analogues (5-6) were isolated from Aspidopterys obcordata vine. Aspidoptoids A-B (1-2) are the first examples of phenylethylene-bearing 20-nor-diterpenoids of which aspidoptoid B (2) possesses a rare 3,10-oxybridge. Their structures and absolute configuration were determined by extensive spectroscopic analyses (IR, HRESIMS, 1D and 2D NMR) and electronic circular dichroism (ECD) calculation. In addition, all the isolates were evaluated for their cytotoxic activities and inhibitory effects on the nitric oxide (NO) production.

Zika Virus Induced More Severe Inflammatory Response Than Dengue Virus in Chicken Embryonic Livers.

Dengue (DENV) and Zika virus (ZIKV) are important flaviviruses in tropical and subtropical regions, causing severe Dengue Hemorrhagic Fever (DHF)/Dengue Shock Syndrome (DSS) and microcephaly, respectively. The infection of both viruses during pregnancy were reported with adverse fetal outcomes. To investigate the effects of ZIKV and DENV infections on fetal development, we established an infection model in chicken embryos. Compared with DENV-2, the infection of ZIKV significantly retarded the development of chicken embryos. High viral loads of both DENV-2 and ZIKV was detected in brain, eye and heart 7 and 11 days post-infection, respectively. Interestingly, only ZIKV but not DENV-2 was detected in the liver. Even both of them induced apparent liver inflammation, ZIKV infection showed a more severe inflammatory response than DENV-2 infection based on the inflammation scores and the gene expression levels of IL-1ß, TNF, IL-6, and TGFß-2 in liver. Our results demonstrated that ZIKV induced more severe inflammatory response in chicken embryo liver compared to DENV-2, which might partially attribute to viral replication in liver cells. Clinicians should be aware of the potential liver injury associated with ZIKV infection in patients, especially in perinatal fetuses.

Broadband light absorption enhancement in randomly rotated elliptical nanohole arrays for photovoltaic application.

Semiconducting nanohole arrays have been considered as a promising candidate for high-efficiency solar cells. In this paper, the optical absorption property of randomly rotated elliptical nanohole arrays consisting of 1×1, 2×2, and 4×4 cells has been investigated. It is found that the average ultimate efficiency of the arrays increases with the increase of the size of the supercell. The 4×4 array has the highest ultimate efficiency, and the efficiency of the 4×4 array is less sensitive to the parameters of the random rotation angle than that of the 1×1 and 2×2 arrays. The comparison of absorption spectra of the three arrays shows that the number of absorption peaks of the 1×1 array is the least, but the peak is the highest and narrowest, and that of the 4×4 array is the most, but the peak is the lowest and broadest. The spatial Fourier spectroscopy analysis of the array shows that the 4×4 arrays have the most Fourier spectrum components and the largest absorption mode density. The enhancement of optical absorption of the 4×4 array is attributed to the folding of energy bands, the increase of the energy density of states caused by large supercells, and the overcoupling between incident light and Bloch resonant modes in the structure. The improved stability of the ultimate efficiency of the 4×4 arrays is because the distribution of the energy density of states of the 4×4 arrays with different random parameters tends to be the same, which leads to almost the same absorption efficiency of the different 4×4 arrays.

Synthesis and structure characterization of sulfated galactomannan from fenugreek gum.

Sulfated derivatives of the galactomannan family have multiple biological activities. In the present study, sulfated galactomannan from fenugreek gum (SFG) were prepared by chlorosulfuric acid/pyridine (CSA/Py) method. In order to acquire the derivatives with the highest degree of substitution (DS), the experiment optimum conditions of the sulfation were determined by Box-Behnken design (BBD). The quadratic regression model analysis confirmed that reaction time was the most significant parameter for the impact of DS. Under the selected conditions, maximum DS was obtained as 0.490. Results of FT-IR and X-ray photoelectron spectroscopy (XPS) indicated the present of SO3- group. In 13C NMR spectroscopy, the original C-6 peaks did not disappear completely and the newly peaks appeared at δ 63.2 and 64.0 illustrating the incomplete substitution were predominantly on C-6 position. After sulfation, size exclusion chromatography combined with multi-angle laser light scattering (SEC-MALLS) detected all the weight average molecular mass (MW) of sulfated derivatives decrease rapidly. The introduction of the electrostatic interaction of negatively charged SO3- groups and the decrease in MW could have a significant effect on its biological activity.

Oxidative stress and NF-κB signaling are involved in LPS induced pulmonary dysplasia in chick embryos.

Inflammation or dysbacteriosis-derived lipopolysaccharides (LPS) adversely influence the embryonic development of respiratory system. However, the precise pathological mechanisms still remain to be elucidated. In this study, we demonstrated that LPS exposure caused lung maldevelopment in chick embryos, including higher embryo mortality, increased thickness of alveolar gas exchange zone, and accumulation of PAS+ immature pulmonary cells, accompanied with reduced expression of alveolar epithelial cell markers and lamellar body count. Upon LPS exposure, pulmonary cell proliferation was significantly altered and cell apoptosis was inhibited as well, indicating a delayed progress of pulmonary development. LPS treatment also resulted in reduced CAV-1 expression and up-regulation of Collagen I, suggesting increased lung fibrosis, which was verified by Masson staining. Moreover, LPS induced enhanced Nrf2 expression in E18 lungs, and the increased reactive oxygen species (ROS) production was confirmed in MLE-12 cells in vitro. Antioxidant vitamin C restored the LPS induced down-regulation of ABCA3, SP-C and GATA-6 in MLE-12 cells. Furthermore, LPS induced activation of NF-κB signaling in MLE-12 cells, and the LPS-induced decrease in SP-C expression was partially abrogated by blocking NF-κB signaling with Bay-11-7082. Bay-11-7082 also inhibited LPS-induced increases of ROS and Nrf2 expression. Taken together, we have demonstrated that oxidative stress and NF-κB signaling are involved in LPS induced disruption of pulmonary cell development in chick embryos.