Intramuscular vitamin A injection in newborn lambs enhances antioxidant capacity and improves meat quality

IntroductionVitamin A (VA) and its metabolite, retinoic acid (RA) possess several biological functions. This report investigated whether neonatal intramuscular VA injection affected antioxidative activity and meat quality in longissimus dorsi (LD) muscle of lambs.MethodsLambs were injected with 0 (control) or 7,500 IU VA palmitate into the biceps femoris muscle on day 2 after birth. At 3, 12, and 32 weeks of age, blood samples were collected in the jugular vein for serum levels of RA and muscle samples were collected in the biceps femoris for analysis of relative mRNA expression of enzyme contributors to retinoid metabolism. All animals were harvested at 32 weeks of age and muscle samples were collected to explore the role of VA on the meat quality and antioxidant capacity of lambs.Results and discussionOur results indicated that VA increased the redness, crude protein, and crude fat (p < 0.05), without affecting moisture, ash, and amino acid composition in LD muscle (p > 0.05). In addition, VA increased catalase (CAT) activity and decreased malondialdehyde (MDA) levels in LD muscle (p < 0.05). Meanwhile, greater levels of CAT and NRF2 mRNA and protein contents with VA treatment were observed in LD muscle (p < 0.05), partly explained by the increased level of RA (p < 0.05). Collectively, our findings indicated that VA injection at birth could improve lamb meat quality by elevating the redness, crude protein, crude fat, and antioxidative capacity in LD muscle of lambs

The psychological impact of the COVID-19 epidemic on college students in China

A COVID-19 epidemic has been spreading in China and other parts of the world since December 2019. The epidemic has brought not only the risk of death from infection but also unbearable psychological pressure. We sampled college students from Changzhi medical college by using cluster sampling. They responded to a questionnaire packet that included the 7-item Generalized Anxiety Disorder Scale (GAD-7) and those inquiring the participants’ basic information. We received 7,143 responses. Results indicated that 0.9% of the respondents were experiencing severe anxiety, 2.7% moderate anxiety, and 21.3% mild anxiety. Moreover, living in urban areas (OR = 0.810, 95% CI = 0.709 - 0.925), family income stability (OR = 0.726, 95% CI = 0.645 - 0.817) and living with parents (OR = 0.752, 95% CI = 0.596 - 0.950) were protective factors against anxiety. Moreover, having relatives or acquaintances infected with COVID-19 was a risk factor for increasing the anxiety of college students (OR = 3.007, 95% CI = 2.377 - 3.804). Results of correlation analysis indicated that economic effects, and effects on daily life, as well as delays in academic activities, were positively associated with anxiety symptoms (P \u3c .001). However, social support was negatively correlated with the level of anxiety (P \u3c .001). It is suggested that the mental health of college students should be monitored during epidemics

Transcriptional Activity of the FUT1 Gene Promoter Region in Pigs

This study aims to provide a theoretical basis on the regulatory mechanism of the α-l,2-fucosyltransferase (FUT1) gene in pigs by analyzing the transcriptional activity of its promoter region. On the basis of the previously obtained promoter sequence, primers upstream and downstream of the gene were designed using the restriction endonucleases KpnI and HindIII respectively, and the recombinant plasmids of the pGL3-promoter were constructed by inserting promoter sequences with partially missing regions. The resultant mutants were observed by transient transfection assay into HEK293 cells, and the transcriptional activity of the promoter region was determined by luciferase activity. The 5'-flanking region of the FUT1 gene (−1150 to +50 bp) exhibited promoter activity. The −1150-bp to −849-bp region showed negative regulation of the gene. The recombinant plasmid pGL3-898 showed the strongest luciferase activity, and the activity showed a decreasing trend when the deleted region was increased. Recombinant plasmids were successfully constructed, verified, and the positive and negative regulation areas and core promoter region were detected, providing a deeper insight into the transcriptional regulatory mechanism of the FUT1 gene

Development of a Strategy for Enhancing the Biomass Growth and Lipid Accumulation of <i>Chlorella</i> sp. UJ-3 Using Magnetic Fe₃O₄ Nanoparticles

In this study, magnetic Fe3O4 nanoparticles (NPs) were used as an effective enhancer to increase the biomass and total lipid production of Chlorella sp. UJ-3. It was found that the biomass of algal cells increased significantly when they were exposed to low concentrations of Fe3O4 NPs (20 mg/L), while the best total lipid content of algal cells was achieved when they were exposed to high concentrations of Fe3O4 NPs (100 mg/L). Therefore, we established a strategy to promote the growth and lipid accumulation of microalgae by initially exposing the algal cells to low concentrations of Fe3O4 NPs and then treating them with an increased concentration of Fe3O4 NPs after 12 days of culture. For this strategy, the biomass and total lipid production of algal cells increased by 50% and 108.7%, respectively, compared to the untreated control. The increase in lipid production and change in the fatty acid composition of Chlorella cells were found to help them to cope with the increased number of reactive oxygen species produced due to oxidative stress in alga cells after the addition of Fe3O4 NPs. This study provided a highly efficient way to improve the lipid production of microalgae using nanoparticles

Review of Biomass Chemical Looping Gasification in China

Biomass chemical looping gasification (BCLG) is a novel and promising technology for syngas production, in which lattice oxygen in oxygen carriers (OCs) reacts with biomass. OCs can continuously supply oxygen for biomass gasification using a redox cycle between different reactors, and the reduced OC can serve as a good catalyst for biomass tar and char cracking, improving the gasification efficiency. The notable advantages of BCLG have attracted attention around the world, particularly in China. Chinese researchers have become the major drivers of the development of BCLG technologies. The experience gained from the experimental tests of BCLG in China is valuable for the further development of BCLG. In this review, we mainly focus on the biomass feedstock, the OC, the tar yield, the reactor, and the results of the BCLG tests in Chinese studies. On the basis of those findings, we summarize the criteria for biomass and the OCs in BCLG, and potential directions for reactor development are briefly discussed. In general, the mechanism of BCLG has been investigated in many studies, and the effects of the operating conditions are relatively wellunderstood. However, there are still few reports on BCLG units that have potential for industrial application. The controllable composition of syngas is worthy of further investigation, and this is required for downstream utilization. Additionally, as a result of the low pollutant emission, chemical looping gasification of solid wastes might be available in the future

Stereoselective and Site-Specific Allylic Alkylation of Amino Acids and Small Peptides via a Pd/Cu Dual Catalysis

We report a stereo­selective and site-specific allylic alkylation of Schiff base activated amino acids and small peptides via a Pd/Cu dual catalysis. A range of noncoded α,α-dialkyl α-amino acids were easily synthesized in high yields and with excellent enantio­selectivities (up to >99% ee). Furthermore, a direct and highly stereo­selective synthesis of small peptides with enantio­pure α-alkyl or α,α-dialkyl α-amino acids residues incorporated at specific sites was accomplished using this dual catalyst system

Analysis of two-dimensional electrophoresis highlighting differentially expressed proteins in duodenal tissues of <i>E</i>. <i>coli</i> F18-resistant and -susceptible individuals.

<p>Analysis of two-dimensional electrophoresis highlighting differentially expressed proteins in duodenal tissues of <i>E</i>. <i>coli</i> F18-resistant and -susceptible individuals.</p

Network of interactions of differentially expressed proteins.

<p>Note: Each circle represents a protein (red, differential protein; blue, linking protein). The area of each circle represents the value of degree, i.e. the extent of interactions between one protein and other proteins.</p

Differential expression of VCL, TF, HSP27 and ACTB proteins in duodenal tissue between <i>E</i>. <i>coli</i> F18-resistant and -susceptible groups, analyzed by western blot.

<p>Each image shows three samples from individual animals.</p

Hydrogen-Bond-Activated Palladium-Catalyzed Allylic Alkylation via Allylic Alkyl Ethers: Challenging Leaving Groups

C–O bond cleavage of allylic alkyl ether was realized in a Pd-catalyzed hydrogen-bond-activated allylic alkylation using only alcohol solvents. This procedure does not require any additives and proceeds with high regioselectivity. The applicability of this transformation to a variety of functionalized allylic ether substrates was also investigated. Furthermore, this methodology can be easily extended to the asymmetric synthesis of enantiopure products (99% ee)