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A new COVID-19 epidemic model with media coverage and quarantine is constructed. The model allows for the susceptibles to the unconscious and conscious susceptible compartment. First, mathematical analyses establish that the global dynamics of the spread of the COVID-19 infectious disease are completely determined by the basic reproduction number R0. If R0 ≤ 1, then the disease free equilibrium is globally asymptotically stable. If R0 > 1, the endemic equilibrium is globally asymptotically stable. Second, the unknown parameters of model are estimated by the MCMC algorithm on the basis of the total confirmed new cases from February 1, 2020 to March 23, 2020 in the UK. We also estimate that the basic reproduction number is R0 = 4.2816(95%CI: (3.8882, 4.6750)). Without the most restrictive measures, we forecast that the COVID-19 epidemic will peak on June 2 (95%CI: (May 23, June 13)) (Figure 3a) and the number of infected individuals is more than 70% of UK population. In order to determine the key parameters of the model, sensitivity analysis are also explored. Finally, our results show reducing contact is effective against the spread of the disease. We suggest that the stringent containment strategies should be adopted in the UK.

An epidemic model with incomplete treatment and vaccination for the newborns and susceptibles is constructed. We establish that the global dynamics are completely determined by the basic reproduction number R0. If R0≤1, then the disease-free equilibrium is globally asymptotically stable. If R0>1, the endemic equilibrium is globally asymptotically stable. Some numerical simulations are also given to explain our conclusions.

The large flying fox (Pteropus vampyrus) is named after its fox-like face and noted for being one of the largest bats. Here, we reported the complete mitogenome sequence ofP. vampyrus,which was 16,554 bp and composed of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one control region, with a base composition of lower G+C content (41.5%). Like other bats, all genes were located on H-strand except for eight tRNA andND6genes. Most protein-coding genes started with an ATG codon except forND2, ND3,andND5, which initiated with ATA or ATT instead, and terminated with the typical stop codon (TAA/TAG) or a single T or an unexpected codon of AGG. Within the control region, 6 bp repeat (TACGCA) was appeared only nine times, much lower than other publishedPteropusspecies. These results provided basic information for researchingPteropus vampyruson genetics, phylogeny, and adaptive evolution. [ABSTRACT FROM AUTHOR]

TheFalco cherrug(Saker falcon) is a large bird of prey. In this article, the complete mitochondrial genome ofF. cherrughas been determined for the first time. The mitogenome (18,059 bp) comprised 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region. Most protein-coding genes started with an ATG or ATA codon except forCOI, which initiated with nontypical start codon of GTG instead, and terminated with the typical stop codon (TAA/TAG/AGA/AGG) or a single T. Two tandem repeats were identified in the control region, which was almost identical toFalco peregrinus, and the length of these two repeats are 204 bp and 291 bp, respectively. [ABSTRACT FROM AUTHOR]

Astatotilapia burtoniis a species of fish in the Cichlidae family.Astatotilapia burtonihas been used as a model organism to research the behaviors and physical systems of cichlids. Here, we reported the complete mitogenome sequence ofA. burtoni, which was 16,583 bp and composed of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region, with a base composition of lower G + C content (45.5%). Similar toAstatotilapia calliptera, all genes were located on H-strand except for eight tRNAs andND6genes. Most protein-coding genes started with an ATG codon except forCOX1, ATP6andND3, which initiated with GTG or ATC instead, and terminated with the typical stop condon (TAA/TAG)or a single T. In this article, 12 protein-coding genes of other 10 closely species were used to construct the species phylogenetic tree to convince the mitogenome sequences. These results provided basic information for researchingA. burtonion genetics, phylogeny and adaptive evolution. [ABSTRACT FROM AUTHOR]

To investigate therapeutic target for ligustrazine during liver fibrosis in an ethanol-induced biliary atresia rat model and transforming growth factor- β (TGF- β ) induced hepatic stellate cell activation cell model, and the underlying mechanism, a total of 30 rats were randomly assigned into five groups ( n = 6 per group): control, sham, ethanol-induced biliary atresia model, model plus pirfenidone, and model plus ligustrazine groups. The liver changes were assessed using H&E and Masson staining and transmission electron microscopy. Expression of miR-145 and mRNA and protein levels of TGF- β /smads pathway-related proteins were detected. HSC-T6 cells were infected with LV-miR or rLV-miR-145 in the presence or absence of SMAD3 inhibitor SIS3 and treated with 2.5 ng/ml TGF- β 1 and then with ligustrazine. Collected cells were subjected to detect the expression of miR-145 and mRNA and protein expression levels of TGF- β /smads pathway-related proteins. Ligustrazine rescued liver fibrogenesis and pathology for ethanol-caused bile duct injury, revealed by decreased α -smooth muscle actin and collagen I expression and liver tissue and cell morphology integrity. Further experiments showed that ligustrazine inhibited intrinsic and phosphorylated Smad2/3 protein expression and modification. Similar results were obtained in cells. In addition, ligustrazine altered miR-145 expression in both animal and cell models. Lentivirus mediated miR-145 overexpression and knockdown recombinant virus showed that miR-145 enhanced the TGF- β /Smad pathway, which led to hepatic stellate cell activation, and ligustrazine blocked this activation. This work validated that ligustrazine-regulated miR-145 mediated TGF- β /Smad signaling to inhibit the progression of liver fibrosis in a biliary atresia rat model and provided a new therapeutic strategy for liver fibrosis. SIGNIFICANCE STATEMENT: With an ethanol-induced biliary atresia rat model, ligustrazine was found to rescue liver fibrogenesis and pathology for ethanol caused bile duct injury, revealed by decreased α -smooth muscle actin and collagen I expression and liver tissue and cell morphology integrity. Furthermore, we found ligustrazine upregulated miR-145 expression and inhibited TGF- β /SMAD signaling pathway both in vivo and in vitro. In addition, overexpression and knockdown of miR-145 confirmed that miR-145 is involved in the ligustrazine inhibition of liver fibrosis through the TGF-β/SMAD signaling pathway., (Copyright © 2022 by The American Society for Pharmacology and Experimental Therapeutics.)