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Human rhinoviruses (HRVs) are the predominant infectious agents for the common cold worldwide. The HRV-C species cause severe illnesses in children and are closely related to acute exacerbations of asthma. 3C protease, a highly conserved enzyme, cleaves the viral polyprotein during replication and assists the virus in escaping the host immune system. These key roles make 3C protease an important drug target. A few structures of 3Cs complexed with an irreversible inhibitor rupintrivir have been determined. These structures shed light on the determinants of drug specificity. Here we describe the structures of HRV-C15 3C in free and inhibitor-bound forms. The volume-decreased S1’ subsite and half-closed S2 subsite, which were thought to be unique features of enterovirus A 3C proteases, appear in the HRV-C 3C protease. Rupintrivir assumes an “intermediate” conformation in the complex, which might open up additional avenues for the design of potent antiviral inhibitors. Analysis of the features of the three-dimensional structures and the amino acid sequences of 3C proteases suggest new applications for existing drugs.

BACKGROUND: Predictors of recurrence in patients with lymph node-negative gastric cancer (GC) who have undergone curative resection have been widely investigated, but not the effects of predictors on timing of recurrence. OBJECTIVE: Determine the factors associated with early and late recurrence in patients with node-negative GC. DESIGN: Retrospective cohort. SETTING: Academic tertiary care center. PATIENTS AND METHODS: The study included patients with node-negative GC after curative resection between 2008 and 2018 at two institutions. Early and late recurrences were determined using a minimum P value approach to evaluate the optimal cutoff for recurrence-free survival (RFS). A competing risk model and landmark analysis were used to analyze factors associated with early and late recurrences. MAIN OUTCOME MEASURES: Recurrence-free survival and factors associated with survival. SAMPLE SIZE: 606. RESULTS: After a median follow-up of 70 months, 50 (8.3%) patients experienced recurrent disease. The optimal length of RFS for distinguishing between early (n=26) and late recurrence (n=24) was 24 months ( P =.0013). The median RFS in the early and late recurrence groups was 11 and 32 months, respectively. Diffuse tumors (hazard ratio 3.358, P =.014), advanced T stage (HR 8.804, P =.003), perineural invasion (HR 10.955, P P =.018) were independent predictors of early recurrence. Mixed tumor location (HR 5.586, P =.002), advanced T stage (HR 5.066, P P P CONCLUSIONS: Individualized therapeutic and follow-up strategies should be considered in future studies because of distinct patterns in predictors of early and late recurrence. LIMITATIONS: Retrospective design, small sample size. CONFLICT OF INTEREST: None.

The majority of outbreaks of the common cold are caused by rhinoviruses. The 2A protease (2Apro) of human rhinoviruses (HRVs) is known to play important roles in the propagation of the virus and the modulation of host signal pathways to facilitate viral replication. The 2Aprofrom human rhinovirus C15 (HRV-C15) has been expressed inEscherichia coliand purified by affinity chromatography, ion-exchange chromatography and gel-filtration chromatography. The crystals diffracted to 2.6 Å resolution. The structure was solved by molecular replacement using the structure of 2Aprofrom coxsackievirus A16 (CVA16) as the search model. The structure contains a conserved His–Asp–Cys catalytic triad and a Zn2+-binding site. Comparison with other 2Aprostructures from enteroviruses reveals that the substrate-binding cleft of 2Aprofrom HRV-C15 exhibits a more open conformation, which presumably favours substrate binding.

Acquired immune deficiency syndrome (AIDS) is mainly caused by the human immunodeficiency virus type-1 (HIV-1). To our knowledge, this is the first review focusing on the vital role of Pin1 in the infection of HIV-1 and the development of AIDS. We and others have demonstrated that Pin1, the only known cis-to-trans isomerase recognizing the pThr/pSer-Pro motifs in proteins, plays striking roles in several human diseases. Interestingly, recent evidence gradually indicates that Pin1 regulates several key steps of the life cycle of HIV-1, including the uncoating of the HIV-1 core, the reverse transcription of the RNA genome of HIV-1, and the integration of the HIV-1 cDNA into human chromosomes. Whereas inhibiting Pin1 suppresses all of these key steps and attenuates the replication of HIV-1, at the same time different PIN1 gene variants are correlated with the susceptibility to HIV-1 infection. Furthermore, Pin1 potentially promotes HIV-1 infection by activating multiple oncogenes and inactivating multiple tumor suppressors, extending the life span of HIV-infected cells. These descriptions suggest Pin1 as a promising therapeutic target for the prevention of HIV-1 and highlight the possibility of blocking the development of AIDS by Pin1 inhibitors.

Small molecule drugs obtained from synthetic compounds or natural products show their therapeutic effects by specifically binding to one or a few target proteins and modulating their functions. In contrast, undesirable drug-protein interactions may provoke harmful side effects. Furthermore, drug-protein interactions also play roles in drug activation, transport, metabolism and regulation of drug resistance. Therefore, systematically identifying binding proteins of a drug molecule is critical for understanding the mechanism of action of the drug at molecular level. In this review, we summarize current widely-used experimental approaches for proteome-wide target identification of small molecule drugs, including affinity purification, chemical proteomics and protein thermal stability based methods. The advance of these methods will quicken the pace of target deconvolution of small molecule drugs and hold promise for drug repositioning research. Moreover, these approaches also provide a powerful arsenal for exploring the signaling pathways of small molecule second messengers, signaling lipids and other regulatory metabolites.

This study aims to investigate the effects of sudden load changes (expected and unexpected imbalance) on the activity of muscles of the lumbar spine and their central motor control strategy in military personnel with or without chronic low back pain (LBP).Bilateral sudden imbalance was examined (2 × 2 factorial design).The 117th PLA Hospital, Hangzhou, ChinaTwenty-one male subjects with lower back pain and 21 male healthy control subjects were active members of the Nanjing Military Region land forces.Independent variables: LBP vs. healthy controls and imbalance anticipation (expected and unexpected imbalance).rapid reaction time (RRT) and intensity of rapid reaction (IRR) of bilateral lumbar (L3-L4) erector spinae (ES), lumbar (L5-S1) multifidus (MF), and abdominal external oblique muscles. Results Under expected or unexpected sudden imbalance conditions, subjects with LBP demonstrated significantly greater IRR than healthy controls in ipsilateral and contralateral ES and MF, respectively (P0.05 for all). IRR of contralateral ES was significantly larger than that of the ipsilateral ES. A significant group effect of RRT of both ipsilateral and contralateral ES muscles and a significant time expectation effect on RRT of contralateral MF muscles were also observed. RRT of the contralateral ES muscles was significantly lower than that of the ipsilateral ES muscles (P0.001).Sudden imbalance prolonged RRT of selected trunk muscles in patients with chronic LBP. The activation amplitude increased. The results may provide a theoretical basis for a study on the pathogenesis of chronic LBP.

The feeding crossbeam on the automatic aluminous-winding machine plays a supporting role in the preparation process of feeding pipe, the deformation of the feeding crossbeam have a direct impact on mechanical accuracy, it is difficult problem in model design, which is how to design a reasonable structure and make the crossbeam meets the requirements of strength and stiffness, as well achieve lightweight design. This article considers the complex force of crossbeam, and bases on the principle of virtual work and finite element theory, using ANASYS software to make a finite element model, the relation curves of the stress and the strain under the maximum load are summarized and the stress concentration area is found, The current study provides more reliable results to improve design.

Potent and selective chemical probes are valuable tools for discovery of novel treatments for human diseases. NF-κB-inducing kinase (NIK) is a key trigger in the development of liver injury and fibrosis. Whether inhibition of NIK activity by chemical probes ameliorates liver inflammation and injury is largely unknown. In this study, a small-molecule inhibitor of NIK, B022, was found to be a potent and selective chemical probe for liver inflammation and injury. B022 inhibited the NIK signaling pathway, including NIK-induced p100-to-p52 processing and inflammatory gene expression, both in vitro and in vivo Furthermore, in vivo administration of B022 protected against not only NIK but also CCl4-induced liver inflammation and injury. Our data suggest that inhibition of NIK is a novel strategy for treatment of liver inflammation, oxidative stress, and injury.-Ren, X., Li, X., Jia, L., Chen, D., Hou, H., Rui, L., Zhao, Y., Chen, Z. A small-molecule inhibitor of NF-κB-inducing kinase (NIK) protects liver from toxin-induced inflammation, oxidative stress, and injury.

Alternative splicing (AS) contributes to the complexity of the mammalian proteome and plays an important role in diseases, including infectious diseases. The differential AS patterns of these transcript sequences between the healthy (HS3A) and mastitic (HS8A) cows naturally infected by Staphylococcus aureus were compared to understand the molecular mechanisms underlying mastitis resistance and susceptibility. In this study, using the Illumina paired-end RNA sequencing method, 1352 differentially expressed genes (DEGs) with higher than twofold changes were found in the HS3A and HS8A mammary gland tissues. Gene ontology and KEGG pathway analyses revealed that the cytokine-cytokine receptor interaction pathway is the most significantly enriched pathway. Approximately 16k annotated unigenes were respectively identified in two libraries, based on the bovine Bos taurus UMD3.1 sequence assembly and search. A total of 52.62% and 51.24% annotated unigenes were alternatively spliced in term of exon skipping, intron retention, alternative 5' splicing and alternative 3' splicing. Additionally, 1,317 AS unigenes were HS3A-specific, whereas 1,093 AS unigenes were HS8A-specific. Some immune-related genes, such as ITGB6, MYD88, ADA, ACKR1, and TNFRSF1B, and their potential relationships with mastitis were highlighted. From Chromosome 2, 4, 6, 7, 10, 13, 14, 17, and 20, 3.66% (HS3A) and 5.4% (HS8A) novel transcripts, which harbor known quantitative trait locus associated with clinical mastitis, were identified. Many DEGs in the healthy and mastitic mammary glands are involved in immune, defense, and inflammation responses. These DEGs, which exhibit diverse and specific splicing patterns and events, can endow dairy cattle with the potential complex genetic resistance against mastitis.

Munc13-1 is an essential component of synaptic vesicle releasing machinery. Three rat Munc13-1 constructs were rationally designed based on homology and function, overexpressed in Escherichia coli, and purified to homogeneity with a final yield higher than 2 microg/ml of cell culture. The purified Munc13-1 recombinant proteins had distinct oligomeric states, monodispersity and homogeneity properties. Their secondary structural contents were analyzed by the circular dichroism method, and the sedimentation coefficients of these recombinant proteins were measured by analytical ultracentrifugation. The long helical bundle-like topology of Munc13-1 was first revealed by analysis of our data. In addition, these purified recombinant proteins provide ideal starting materials for further biochemical, biophysical, and structural studies on mammalian Munc13 proteins.

Centrins are four-EF-hand Ca(2+)-binding proteins, which belong to the CaM super family. The centrin from ciliate Euplotes Octocarinatus has been expressed in Escherichia coli, purified and crystallized using the hanging-drop method. Rod-like crystals were grown and diffracted to 2.0 angstroms. The crystals belong to space group P2(1)2(1)2(1) and the unit-cell parameters are a=34.442 angstroms, b=48.954 angstroms, c=72.583 angstroms.

THE amphisbaenians, lizards and snakes constitute a monophyletic group, the Squamata. Although amphisbaenians are known to have occurred in the Mesozoic1,2, their remains are rare and fragmentary. The oldest and most primitive known skull of an amphisbaenian is from the Eocene of North America3 and differs little from that of modern taxa4–9. A substantial structural gap exists between this skull and that of the several possible sister groups8,10. No derived features uniquely linking amphisbaenians to any other group of the Squamata have been recognized, so the relationship of amphisbaenians is uncertain11,12. We report here on the late Cretaceous lizard-like amphisbaenian represented by well-preserved cranial and postcranial material from the Bayan Mandahu redbeds of the Gobi Desert, Inner Mongolia, China. This material documents the oldest and most primitive amphisbaenian yet known, and permits a re-evaluation of the relationship between the amphisbaenians and other squamates.