Inhibitory effects and molecular mechanisms of tetrahydrocurcumin against human breast cancer MCF-7 cells

Background: Tetrahydrocurcumin (THC), an active metabolite of curcumin, has been reported to have similar biological effects to curcumin, but the mechanism of the antitumor activity of THC is still unclear. Methods: The present study was to investigate the antitumor effects and mechanism of THC in human breast cancer MCF-7 cells using the methods of MTT assay, LDH assay, flow cytometry analysis, and western blot assay. Results: THC was found to have markedly cytotoxic effect and antiproliferative activity against MCF-7 cells in a dose-dependent manner with the IC50 for 24 h of 107.8 μM. Flow cytometry analysis revealed that THC mediated the cell-cycle arrest at G0/G1 phase, and 32.8% of MCF-7 cells entered the early phase of apoptosis at 100 μM for 24 h. THC also dose-dependently led to apoptosis in MCF-7 cells via the mitochondrial pathway, as evidenced by the activation of caspase-3 and caspase-9, the elevation of intracellular ROS, a decrease in Bcl-2 and PARP expression, and an increase in Bax expression. Meanwhile, cytochrome C was released to cytosol and the loss of mitochondria membrane potential (Δψm) was observed after THC treatment. Conclusion: THC is an excellent source of chemopreventive agents in the treatment of breast cancer and has excellent potential to be explored as antitumor precursor compound

Characteristics and purification of Himalayan salt by high temperature melting

Himalayan rock salt contains a variety of minerals and trace elements, which is conducive to human health. The solutions of black rock salt and rose salt are alkaline, and the content of water insoluble matter is 0.34 and 0.083%, respectively. The element composition of water insoluble matter in rock salt is determined and analyzed. It is found that the main component of two kinds of rock salt water insoluble matter is soil. Due to the presence of water insoluble matter in rock salt, according to the different specific gravity of molten sodium chloride and insoluble matter, rock salt was purified by high-temperature melting method. Rose salt is mainly studied during purification. The results showed that the content of insoluble matter in rose salt decreased from 0.083 to 0.0024% after holding at 950°C for 40 min; the contents of arsenic, barium, and lead decreased to 0.0032, 0.61, and 0.21 mg·kg−1, respectively; the content of sodium increased to 39.24%, the contents of calcium, magnesium, and iron reached to 2,200, 855, and 1.31 mg·kg−1, respectively

Effect of population migration and socioeconomic factors on the COVID-19 epidemic at county level in Guangdong, China

Coronavirus disease 2019 (COVID-19) has become a major public health concern worldwide. In this study, we aimed to analyze spatial clusters of the COVID-19 epidemic and explore the effects of population emigration and socioeconomic factors on the epidemic at the county level in Guangdong, China. Data on confirmed cases, population migration, and socioeconomic factors for 121 counties were collected from 1 December 2019 to 17 February 2020, during which there were a total of 1,328 confirmed cases. County-level infected migrants of Guangdong moving from Hubei were calculated by integrating the incidence rate, population migration data of Baidu Qianxi, and the resident population. Using the spatial autocorrelation method, we identified high-cluster areas of the epidemic. We also used a geographical detector to explore infected migrants and socioeconomic factors associated with transmission of COVID-19 in Guangdong. Our results showed that: 1) the epidemic exhibited significant positive global spatial autocorrelation; high–high spatial clusters were mainly distributed in the Pearl River Estuary region; 2) city-level population migration data corroborated with the incidence rate of each city in Hubei showed significant association with confirmed cases; 3) in terms of potential factors, infected migrants greatly contributed to the spread of COVID-19, which has strong ability to explain the COVID-19 epidemic; besides, the companies, transport services, residential communities, restaurants, and community facilities were also the dominant factors in the spread of the epidemic; 4) the combined effect produced by the intersecting factors can increase the explanatory power. The infected migrant factor interacted strongly with the community facility factor with the q value of 0.895. This indicates that the interaction between infected migrants and community facilities played an important role in transmitting COVID-19 at the county level

Recovery of Vanadium from H2SO4-HF Acidic Leaching Solution of Black Shale by Solvent Extraction and Precipitation

The recovery of vanadium from sulfuric and hydrofluoric mixed acid solutions generated by the direct leaching of black shale was investigated using solvent extraction and precipitation methods. The process consisted of reduction, solvent extraction, and stripping, followed by precipitation and calcination to yield vanadium pentoxide. The influence of various operating parameters on the extraction and recovery of vanadium was studied. Vanadium (IV) was selectively extracted using a mixture of 10% (v/v) di(2-ethylhexyl)phosphoric acid and 5% (v/v) tri-n-butylphosphate in sulfonated kerosene. Using six extraction and five stripping stages, the extraction efficiency for vanadium was 96.7% and the stripping efficiency was 99.7%. V2O5 with a purity of 99.52% was obtained by oxidation of the loaded strip solution and precipitation of ammonium polyvanadate at pH 1.8 to 2.2, followed by calcination of the dried precipitate at 550 °C for 2 h. It was concluded that the combination of solvent extraction and precipitation is an efficient method for the recovery of vanadium from a multi-element leach solution generated from black shale

Novel Downhole Electromagnetic Flowmeter for Oil-Water Two-Phase Flow in High-Water-Cut Oil-Producing Wells

First, the measuring principle, the weight function, and the magnetic field of the novel downhole inserted electromagnetic flowmeter (EMF) are described. Second, the basic design of the EMF is described. Third, the dynamic experiments of two EMFs in oil-water two-phase flow are carried out. The experimental errors are analyzed in detail. The experimental results show that the maximum absolute value of the full-scale errors is better than 5%, the total flowrate is 5–60 m3/d, and the water-cut is higher than 60%. The maximum absolute value of the full-scale errors is better than 7%, the total flowrate is 2–60 m3/d, and the water-cut is higher than 70%. Finally, onsite experiments in high-water-cut oil-producing wells are conducted, and the possible reasons for the errors in the onsite experiments are analyzed. It is found that the EMF can provide an effective technology for measuring downhole oil-water two-phase flow

Surface Confinement of FeNiCo Nanoparticles by Bicontinuous Conductive Networks toward Overall Water Splitting

The development of low-cost and high-performance dual-function electrocatalysts for stable water electrolysis is crucial for realizing a sustainable energy supply. Herein, the conductive carbon layer confined ultrasmall FeNiCo trimetallic nanoparticles are successfully synthesized directly on a carbon cloth surface. The outer carbon shell can act as a protective armor and confinement structure to anchor and confine the nanoparticles. The ultrathin carbon coating layer effectively shortens the charge diffusion pathways, while the direct contact between active nanoparticles and the current collector enhances the electron conductivity. Therefore, the average size of the metal nanoparticles is only 8.8 nm, which greatly increases the effective surface area and enhances the exposure of active sites. Thus, the optimized 0.25C@FeNiCo/CC and 0.75C@FeNiCo/CC composites reveal onset overpotentials of 46 and 236 mV in HER/OER, respectively. The cell voltage for water electrolysis is only 1.59 V at 20 mA cm–2 with high stability for 40 h. This rational design strategy of carbon-supported ultrasmall multimetal nanoparticles and fast electron/ion transfer pathways provides an effective strategy for design of highly efficient bifunctional electrocatalysts for overall water splitting

Comparative Secretome Analysis of Magnaporthe oryzae Identified Proteins Involved in Virulence and Cell Wall Integrity

Plant fungal pathogens secrete numerous proteins into the apoplast at the plant–fungus contact sites to facilitate colonization. However, only a few secretory proteins were functionally characterized in Magnaporthe oryzae, the fungal pathogen causing rice blast disease worldwide. Asparagine-linked glycosylation 3 (Alg3) is an α-1,3-mannosyltransferase functioning in the N-glycan synthesis of N-glycosylated secretory proteins. Fungal pathogenicity and cell wall integrity are impaired in Δalg3 mutants, but the secreted proteins affected in Δalg3 mutants are largely unknown. In this study, we compared the secretomes of the wild-type strain and the Δalg3 mutant and identified 51 proteins that require Alg3 for proper secretion. These proteins were predicted to be involved in metabolic processes, interspecies interactions, cell wall organization, and response to chemicals. Nine proteins were selected for further validation. We found that these proteins were localized at the apoplastic region surrounding the fungal infection hyphae. Moreover, the N-glycosylation of these proteins was significantly changed in the Δalg3 mutant, leading to the decreased protein secretion and abnormal protein localization. Furthermore, we tested the biological functions of two genes, INV1 (encoding invertase 1, a secreted invertase) and AMCase (encoding acid mammalian chinitase, a secreted chitinase). The fungal virulence was significantly reduced, and the cell wall integrity was altered in the Δinv1 and Δamcase mutant strains. Moreover, the N-glycosylation was essential for the function and secretion of AMCase. Taken together, our study provides new insight into the role of N-glycosylated secretory proteins in fungal virulence and cell wall integrity