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On March 30, 2013, a novel avian influenza A H7N9 virus that infects human beings was identified. This virus had been detected in six provinces and municipal cities in China as of April 18, 2013. We correlated genomic sequences from avian influenza viruses with ecological information and did phylogenetic and coalescent analyses to extrapolate the potential origins of the virus and possible routes of reassortment events. We downloaded H7N9 virus genome sequences from the Global Initiative on Sharing Avian Influenza Data (GISAID) database and public sequences used from the Influenza Virus Resource. We constructed phylogenetic trees and did 1000 bootstrap replicates for each tree. Two rounds of phylogenetic analyses were done. We used at least 100 closely related sequences for each gene to infer the overall topology, removed suspicious sequences from the trees, and focused on the closest clades to the novel H7N9 viruses. We compared our tree topologies with those from a bayesian evolutionary analysis by sampling trees (BEAST) analysis. We used the bayesian Markov chain Monte Carlo method to jointly estimate phylogenies, divergence times, and other evolutionary parameters for all eight gene fragments. We used sequence alignment and homology-modelling methods to study specific mutations regarding phenotypes, specifically addressing the human receptor binding properties. The novel avian influenza A H7N9 virus originated from multiple reassortment events. The HA gene might have originated from avian influenza viruses of duck origin, and the NA gene might have transferred from migratory birds infected with avian influenza viruses along the east Asian flyway. The six internal genes of this virus probably originated from two different groups of H9N2 avian influenza viruses, which were isolated from chickens. Detailed analyses also showed that ducks and chickens probably acted as the intermediate hosts leading to the emergence of this virulent H7N9 virus. Genotypic and potential phenotypic differences imply that the isolates causing this outbreak form two separate subclades. The novel avian influenza A H7N9 virus might have evolved from at least four origins. Diversity among isolates implies that the H7N9 virus has evolved into at least two different lineages. Unknown intermediate hosts involved might be implicated, extensive global surveillance is needed, and domestic-poultry-to-person transmission should be closely watched in the future. China Ministry of Science and Technology Project 973, National Natural Science Foundation of China, China Health and Family Planning Commission, Chinese Academy of Sciences.

The purpose of the study is to provide a method for mass production of nicotinamide mononucleotide (NMN) using an immobilized nicotinamide riboside kinase (NMRK). We synthesized a gene sequence comprising the gene encoding the enzyme. At the 3’ end of this NMRK-encoding gene, an optimized cellulose-binding domain (CBD) sequence was linked via a linker-encoding gene segment.Using the pET-32a plasmid as the vector and Escherichia coli BL21(DE3) as the host cell, the recombinant E. coli strain BL21/pET-32a-nmrk-1 was constructed and cultivated. This recombinant strain BL21/pET-32a-nmrk-1 secreted a significantly higher yield of the NMRK enzyme protein (32 mg/mL), and the secreted recombinant NMRK enzyme exhibited superior activity (80 U/g). Activated microcrystalline cellulose was mixed with the crude enzyme solution containing the recombinant NMRK enzyme. Following processing, the immobilized NMRK enzyme was obtained. This immobilized enzyme catalyzed the synthesis of NMN from 0.07 mol/L nicotinamide riboside (NR), achieving a conversion rate of 90% and a purity of 33%. The recombinant NMRK enzyme retained good activity after immobilization onto the carrier, enabling its reuse for more than 10 cycles. The initial activity of the immobilized NMRK enzyme was 540 U/g. After 11 cycles of use, the activity was 390 U/g, representing only a 27.8% decline in activity. This approach enhances the utilization efficiency of the NMRK enzyme while simultaneously reducing the production cost of NMN.

The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the world is still expanding. Thus, there is an urgent need to better understand this novel virus and find a way to control its spread. Like other coronaviruses, the nucleocapsid (N) protein is one of the most crucial structural components of SARS-CoV-2. This protein shares 90% homology with the severe acute respiratory syndrome coronavirus N protein, implying functional significance. Based on the evolutionary conservation of the N protein in coronavirus, we reviewed the currently available knowledge regarding the SARS-CoV-2 N protein in terms of structure, biological functions, and clinical application as a drug target or vaccine candidate.

Pseudorabies virus (PRV) has evolved various immune evasion mechanisms that target host antiviral immune responses. However, it is unclear whether and how PRV encoded proteins modulate the cGAS-STING axis for immune evasion. Here, we show that PRV tegument protein UL13 inhibits STING-mediated antiviral signaling via regulation of STING stability. Mechanistically, UL13 interacts with the CDN domain of STING and recruits the E3 ligase RING-finger protein 5 (RNF5) to promote K27-/K29-linked ubiquitination and degradation of STING. Consequently, deficiency of RNF5 enhances host antiviral immune responses triggered by PRV infection. In addition, mutant PRV lacking UL13 impaired in antagonism of STING-mediated production of type I IFNs and shows attenuated pathogenicity in mice. Our findings suggest that PRV UL13 functions as an antagonist of IFN signaling via a novel mechanism by targeting STING to persistently evade host antiviral responses.

A better understanding of dough rheology during processing is crucial in the bakery industry, since quality attributes of the final product are influenced by those properties. In this study, we investigated the effects of xylanase, α-amylase and cellulase on the rheological properties of bread dough enriched in oat bran. A DoughLAB was used to measure the mixing characteristics of dough. According to the results, adding a single enzyme did not significantly affect the water absorption, development time, or stability of oat bran dough. In contrast, when blended enzymes were used at high concentrations (10, 120, and 60 ppm), the water absorption, development time, and stability of the oat bran dough were significantly reduced compared to using the single enzyme (62.1%, 7.1 and 6.6 min). It was found that combining α-amylase, xylanase and cellulase resulted in better extensibility and stickiness (16.5 mm and 60.8 g) of oat bran dough than using these enzymes individually. As a result, α-amylase, xylanase and cellulase complemented each other in determining the rheology of bread dough.

High performance X-ray detector with ultra-high spatial and temporal resolution are crucial for biomedical imaging. This study reports a dynamic direct-conversion CMOS X-ray detector assembled with screen-printed CsPbBr 3 , whose mobility-lifetime product is 5.2 × 10 −4  cm 2  V –1 and X-ray sensitivity is 1.6 × 10 4  µC Gy air –1  cm –2 . Samples larger than 5 cm × 10 cm can be rapidly imaged by scanning this detector at a speed of 300 frames per second along the vertical and horizontal directions. In comparison to traditional indirect-conversion CMOS X-ray detector, this perovskite CMOS detector offers high spatial resolution (5.0 lp mm −1 ) X-ray radiographic imaging capability at low radiation dose (260 nGy). Moreover, 3D tomographic images of a biological specimen are also successfully reconstructed. These results highlight the perovskite CMOS detector’s potential in high-resolution, large-area, low-dose dynamic biomedical X-ray and CT imaging, as well as in non-destructive X-ray testing and security scanning. Biomedical X-ray imaging requires high spatial and temporal resolution of the detectors. Liu et al. report a screen-printed perovskite direct-conversion X-ray CMOS imager with a spatial resolution of 5 lp mm −1 and a speed of 300 fps for low-dose 2D radiography and 3D computed tomography imaging.

Coronavirus disease 2019 (COVID-19) was first identified in late 2019 in Wuhan, Hubei Province, China and spread globally in months, sparking worldwide concern. However, it is unclear whether super-spreading events occurred during the early outbreak phase, as has been observed for other emerging viruses. Here, we analyse 208 publicly available SARS-CoV-2 genome sequences collected during the early outbreak phase. We combine phylogenetic analysis with Bayesian inference under an epidemiological model to trace person-to-person transmission. The dispersion parameter of the offspring distribution in the inferred transmission chain was estimated to be 0.23 (95% CI: 0.13–0.38), indicating there are individuals who directly infected a disproportionately large number of people. Our results showed that super-spreading events played an important role in the early stage of the COVID-19 outbreak. Although SARS-CoV-2 has spread rapidly, the contribution of super-spreading events to transmission is unclear. Here, the authors show that the number of secondary infections arising from an individual infection in the early phase of the outbreak was highly skewed, indicating that super-spreading events occurred.

Over 50% cancer bears TP53 mutation, the highly stabilized mutant p53 protein drives the tumorigenesis and progression. Mutation of p53 not only cause loss-of-function and dominant-negative effects (DNE), but also results in the abnormal stability by the regulation of the ubiquitin-proteasome system and molecular chaperones that promote tumorigenesis through gain-of-function effects. The accumulation of mutant p53 is mainly regulated by molecular chaperones, including Hsp40, Hsp70, Hsp90 and other biomolecules such as TRIM21, BAG2 and Stat3. In addition, mutant p53 forms prion-like aggregates or complexes with other protein molecules and result in the accumulation of mutant p53 in tumor cells. Depleting mutant p53 has become one of the strategies to target mutant p53. This review will focus on the mechanism of mutant p53 stabilization and discuss how the strategies to manipulate these interconnected processes for cancer therapy.

: Diquat has replaced paraquat in agricultural areas as a herbicide but has led to extensive poisoning. Unlike paraquat, which targets the lungs, diquat primarily targets the kidneys. Autopsies and animal experiments suggest that interstitial kidney damage is the most critical renal lesion. Diquat is a nonselective chemical widely used for terrestrial and aquatic plants after the ban on paraquat. Although diquat is known to affect the kidneys mainly, no study has reported renal biopsy in patients with diquat poisoning. : We investigated the histopathologic feature in a young man with diquat poisoning who developed acute kidney injury by renal biopsy. : Autopsy and animal experiments suggest that interstitial kidney inflammation is the most critical renal lesion. Surprisingly, our results showed that lipid degeneration and acute tubular injury with limited interstitial inflammation were the dominant histologic findings in this patient. : Based on a renal biopsy, this was the first study describing the characteristics of the kidney affected by diquat poisoning. Our findings might provide information for managing patients who develop AKI due to diquat poisoning.