Genetic characterization and molecular epidemiological analysis of enterovirus C99 in China.

Enterovirus C99 (EV-C99) is a newly identified EV serotype within the species Enterovirus C. Few studies on EV-C99 have been conducted globally. More information and research on EV-C99 are needed to assess its genetic characteristics, phylogenetic relationships, and associations with enteroviral diseases. Here, the phylogenetic characteristics of 11 Chinese EV-C99 strains have been reported. The full-length genomic sequences of these 11 strains show 79.4-80.5% nucleotide identity and 91.7-94.3% amino acid (aa) identity with the prototype EV-C99. A maximum likelihood phylogenetic tree constructed based on the entire VP1 coding region identified 13 genotypes (A-M), revealing a high degree of variation among the EV-C99 strains. Phylogeographic analysis showed that the Xinjiang Uygur Autonomous Region is an important source of EV-C99 epidemics in various regions of China. Recombination analysis revealed inter-serotype recombination events of 16 Chinese EV-C99 strains in 5' untranslated regions and 3D regions, resulting in the formation of a single recombination form. Additionally, the Chinese strain of genotype J showed rich aa diversity in the P1 region, indicating that the genotype J of EV-C99 is still going through variable dynamic changes. This study contributes to the global understanding of the EV-C99 genome sequence and holds substantial implications for the surveillance of EV-C99.

Identification and genetic characterization of a recently identified enterovirus C116 in China.

Enterovirus C116 (EV-C116) is a new member of the enterovirus C group which is closely associated with several infectious diseases. Although sporadic studies have detected EV-C116 in clinical samples worldwide, there is currently limited information available. In this study, two EV-C-positive fecal specimens were detected in apparently healthy children, which harbored low abundance, through meta-transcriptome sequencing. Based on the prototypes of several EV-Cs, two lineages were observed. Lineage 1 included many types that could not cause EV-like cytopathic effect in cell culture. Three genogroups of EV-C116 were divided in the maximum likelihood tree, and the two strains in this study (XZ2 and XZ113) formed two different lineages, suggesting that EV-C116 still diffuses worldwide. Obvious inter-type recombination events were observed in the XZ2 strain, with CVA22 identified as a minor donor. However, another strain (XZ113) underwent different recombination situations, highlighting the importance of recombination in the formation of EV-Cs biodiversity. The EV-C116 strains could propagate in rhabdomyosarcoma cell cultures at low titer; however, EV-like cytopathic effects were not observed. HEp-2, L20B, VERO, and 293T cell lines did not provide an appropriate environment for EV-C116 growth. These results challenge the traditional recognition of the uncultured nature of EV-C116 strains and explain the difficulty of clinical detection.

Inflammatory damage caused by Echovirus 30 in the suckling mouse brain and HMC3 cells.

Echovirus 30 (E30), a member of the species B Enterovirus family, is a primary pathogen responsible for aseptic meningitis and encephalitis. E30 is associated with severe nervous system diseases and is a primary cause of child illness, disability, and even mortality. However, the mechanisms underlying E30-induced brain injury remain poorly understood. In this study, we used a neonatal mouse model of E30 to investigate the possible mechanisms of brain injury. E30 infection triggered the activation of microglia in the mouse brain and efficiently replicated within HMC3 cells. Subsequent transcriptomic analysis revealed inflammatory activation of microglia in response to E30 infection. We also detected a significant upregulation of polo-like kinase 1 (PLK1) and found that its inhibition could limit E30 infection in a sucking mouse model. Collectively, E30 infection led to brain injury in a neonatal mouse model, which may be related to excessive inflammatory responses. Our findings highlight the intricate interplay between E30 infection and neurological damage, providing crucial insights that could guide the development of interventions and strategies to address the severe clinical manifestations associated with this pathogen.

Efficacy and safety of tetrandrine in treatment of rheumatoid arthritis: a meta analysis. / æ±‰é˜²å·±ç”²ç´ æ²»ç–—ç±»é£Žæ¹¿å ³èŠ‚ç‚Žæœ‰æ•ˆæ€§å’Œå®‰å ¨æ€§çš„meta分析.

OBJECTIVES: To explore the efficacy and safety of tetrandrine in the treatment of rheumatoid arthritis. METHODS: Randomized controlled studies of tetrandrine in the treatment of rheumatoid arthritis were searched in China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), World Wide Web Database, SinoMed, PubMed, Springer, Web of Science, the Cochrane Central Register of Controlled Trails database. A meta-analysis was conducted using R software version 3.5.3 to evaluate the clinical outcomes, including the total effective rate, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), visual analog scale (VAS) for pain, disease activity score (DAS), tender joint count (TJC), swollen joint count (SJC), and morning stiffness duration, as well as adverse events of RA patients. RESULTS: A total of 10 articles were included in the study. The meta-analysis indicated that tetrandrine significantly improved the total effective rate (OR=3.27, 95%CI: 2.01-5.37, P<0.01), ESR (SMD=1.12, 95%CI: 0.06-2.19, P<0.05), CRP (SMD=0.75, 95%CI: 0.28-1.22, P<0.01), VAS (SMD=0.55, 95%CI: 0.21-0.89, P<0.01), SJC (SMD=0.85, 95%CI: 0.40-1.31, P<0.01), TJC (SMD=1.16, 95%CI: 0.58-1.74, P<0.01), and morning stiffness (SMD=1.09, 95%CI: 0.68-1.50, P<0.01). However, no statistical significance was found in RF (SMD=1.70, 95%CI: －1.10-4.51, P>0.05) and DAS (SMD=0.26, 95%CI: －0.59-1.11, P>0.05). The overall incidence of adverse events associated with tetrandrine treatment for rheumatoid arthritis was 20% (95%CI: 12%-27%, I2=60%, P<0.05), with mild severity and favorable outcomes. CONCLUSIONS: Tetrandrine is effective in the treatment of RA patients with a mild degree of adverse events.

Pathological Characteristics of Echovirus 30 Infection in a Mouse Model.

Echovirus 30 (E30), a member of species B enterovirus, is associated with outbreaks of aseptic meningitis and has become a global health emergency. However, the pathogenesis of E30 remains poorly understood due to the lack of appropriate animal models. In this study, we established a mouse infection model to explore the pathogenicity of E30. The 2-day-old IFNAR-/- mice infected with E30 strain WZ16 showed lethargy and paralysis, and some died. Obvious pathological changes were observed in the skeletal muscle, brain tissue, and other tissues, with the highest viral load in the skeletal muscles. Transcriptome analysis of brain and skeletal muscle tissues from infected mice showed that significant differentially expressed genes were enriched in complement response and neuropathy-related pathways. Using immunofluorescence assay, we found that the viral double-stranded RNA (dsRNA) was detected in the mouse brain region and could infect human glioma (U251) cells. These results indicated that E30 affects the nervous system, and they provide a theoretical basis for understanding its pathogenesis. IMPORTANCE Echovirus 30 (E30) infection causes a wide spectrum of diseases with mild symptoms, such as hand, foot, and mouth disease (HFMD), acute flaccid paralysis, and aseptic meningitis and other diseases, especially one of the most common pathogens causing aseptic meningitis outbreaks. We established a novel mouse model of E30 infection by inoculating neonatal mice with clinical isolates of E30 and observed the pathological changes induced by E30. Using the E30 infection model, we found complement responses and neuropathy-related genes in the mice tissues at the transcriptome level. Moreover, we found that the viral dsRNA localized in the mouse brain and could replicate in human glioma cell line U251 rather than in the neuroblastoma cell line, SK-N-SH.

Relationship of biglycan and decorin expression with clinicopathological features and prognosis in patients with oral squamous cell carcinoma.

OBJECTIVE: This study focused on investigating relation between biglycan (BGN) and decorin (DCN) expression and prognostic outcome for oral squamous cell carcinoma (OSCC) cases. MATERIAL AND METHODS: BGN and DCN mRNA and protein expression was detected by qRT-PCR and Western-blotting (WB) assays from 31 OSCC samples as well as healthy samples. This work harvested 101 paraffin-embedded OSCC together with 30 healthy samples, and conducted immunohistochemical (IHC) staining for assessing pathological changes. Association of DCN with BGN within OSCC was explored by Spearman's analysis. Survival rate was explored by Kaplan-Meier (KM) approach. Multivariate analysis was conducted by Cox regression. RESULTS: WB and qRT-PCR results showed BGN up-regulation (p < 0.001, p < 0.0001) whereas DCN down-regulation (p < 0.0001, p < 0.0001) with fresh OSCC tissues; the expression of BGN and DCN associated with the OSCC histopathological grade. IHC results suggested elevated BGN level (p < 0.0001) whereas DCN down-regulation (p < 0.0001) with paraffin embedded OSCC tissues. The expression of BGN and DCN associated with histopathologic grades and tumor stage of OSCC. The result of Spearman's analysis demonstrated significant association between the expression of BGN and DCN in OSCC. Survival analysis revealed that patients with higher BGN/lower DCN level showed poor overall survival (OS) as well as tumor-specific survival (TSS). Multivariate analysis proved that BGN and DCN independently predicted the prognosis of OS and TSS. CONCLUSION: BGN and DCN expression levels can be adopted for predicting OSCC prognostic outcome.

Effects of temperature on microstructures of MSA-type electroplating solution: a coarse-grained molecular dynamics simulation.

In this study, we employ coarse-grained molecular dynamics simulations to explore the microstructure of MSA (methanesulfonic acid)-type electroplating solution, containing Sn(MSA)2 as the primary salt, MSA as the stabilizer, amphiphilic alkylphenol ethoxylate (APEO) as surfactants and cinnamaldehyde (CA) as the brightener agents, as well as water as the solvent. Our simulation indicates that temperature variations can significantly affect the structural properties of the electroplating solution and the adsorption behavior of its key components onto the substrate. Specifically, at low temperatures, the primary salt ions aggregate into ionic clusters, and the amphiphilic APEO surfactants and CA molecules form micelles composed of hydrophobic cores and hydrophilic shells, which reduces the uniformity of the solution and hinders the adsorption of ions, CA and surfactants onto the substrate. Appropriately increasing the temperature can weaken the aggregation of these components in bulk solution due to the accelerated molecular movements and arouse their adsorption. However, on further increasing the temperature, the elevated kinetic energy of the components thoroughly overwhelms the adsorption interactions, and therefore, the ions, surfactants, and CA desorb from the substrate and redissolve into the solution. We systematically analyze the complex interactions between these components at different temperatures and clarify the mechanism of the non-monotonic dependence of adsorption strength on the temperature at the molecular level. Our simulations demonstrate that there is low-temperature scope for reprocessing/recycling and intermediate-temperature scope for substrate-adsorptions of the key components. This study confers insights into a fundamental understanding of the microscopic mechanism for electroplating and can provide guidance for the development of precise electroplatings.

Evaluation of CK19 and VEGF gene expression, ki67 antigen, p53 protein, C-erb-B2, and their relationship in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is one of the ten most common malignant tumors globally. This study aimed to evaluate the expression changes of Cytokeratin 19 (CK19), vascular endothelial growth factor (VEGF), P53, ki67, and c-ert-B2 in OSCC patients. For this purpose, 30 patients were selected as the case group and 30 healthy individuals as the control group. The expression of CK19 and VEGF genes in their blood serum was measured. Also, the expression of ki67, P53, and c-ert-B2 markers in squamous cell carcinoma was evaluated using immunohistochemistry. T-test was used to analyze the data. The results showed that the presence of CK19 marker in people with OSCC was positive in 17 out of 30 patients and VEGF marker in 23 out of 30 patients. The mean of ki67 positive, P53 positive, and Cerb-B2 positive cells were 399.4, 221.4, and 26.8, respectively. The correlation test between the indices showed a statistical correlation between the incidence of ki67 and P53 (r = 91.5% and p = 0.02). While statistical correlation was not seen between the incidence of ki67 and Cerb-B2 index (r = -1.7% and p = 0.97) and P53 and C-erb-B2 index (r = -13% and p = 0.8) (p <0.05). In general, the expression of VEGF and CK19 genes is higher in patients with OSCC than in healthy individuals. Therefore, examining the expression level of these two biomarkers in the blood of OSCC patients can be considered as a diagnostic screening method in the early stages of the disease. The immunohistochemical study of squamous cell carcinoma can also be used as a diagnostic screening test in the early stages of the disease.

A transferrable range-separated force field for water: Combining the power of both physically-motivated models and machine learning techniques.

An accurate, transferrable, and computationally efficient potential energy surface is of paramount importance for all molecular mechanics simulations. In this work, by using water as an example, we demonstrate how one can construct a reliable force field by combining the advantages of both physically motivated and data-driven machine learning methods. Different from the existing water models based on molecular many-body expansion, we adopt a separation scheme that is completely based on distances, which is more convenient for generic molecular systems. The geometry dependence of atomic charges and dispersion coefficients are also introduced to improve the accuracy of the long-range part of the potential. The new potential provides a physically interpretable energy decomposition, and it is more accurate than the conventional physically motived potentials. Most importantly, through this study, we show that the information we learn from small clusters can be extrapolated into larger systems, thus providing a general recipe for the intermolecular force field development at the coupled-cluster singles and doubles plus perturbative triples level of theory in the future.

NUDT1: A potential independent predictor for the prognosis of patients with oral squamous cell carcinoma.

OBJECTIVE: The current study was aimed to investigate the association of nudix hydrolase 1 (NUDT1) levels with the prognosis of oral squamous cell carcinoma (OSCC) patients. MATERIAL AND METHODS: Western immunoblotting and qRT-PCR were used to detect the protein and mRNA levels of NUDT1 in 31 cases of OSCC and normal tissues. The paraffin-embedded 62 cases of OSCC and 18 normal tissues were collected, and the pathological alterations were assessed by immunohistochemistry. The prognosis of all patients was followed up. Kaplan-Meier method was used to analyze the survival rate, and Cox regression was used for multivariate analysis. RESULTS: Both the protein and gene levels of NUDT1 were statistically increased (P = .0007 and P < .0001) in the OSCC tissue and had a significant association with the histopathologic grades of OSCC (P < .0001 and P = .0223). Immunohistochemistry detection of NUDT1 in 62 human OSCC tissues and 18 normal control tissues showed that NUDT1 expression was significantly increased in OSCC tissue and showed a strong association with histopathologic grades (P < .0001) and tumor stage (P = .005). Patients with high NUDT1 expression exhibited poorer overall survival rate (OS) and tumor-specific survival rate (TSS) than those with low NUDT1 expression (P < .0001 and P = .0008), and NUDT1 was independent prognostic factors for OS and TSS (P < .0001 and P < .001). CONCLUSION: The expression level of NUDT1 might be used to predict the prognosis of OSCC patients.

Effect of Retro-Inverso Isomer of Bradykinin on Size-Dependent Penetration of Blood-Brain Tumor Barrier.

Retro-inverso bradykinin (RI-BK) has better metabolic stability and higher affinity for the BK type 2 (B2) receptor, compared with bradykinin. At low doses, RI-BK can selectively enhance the permeability of the blood-brain tumor barrier (BBTB) without harming normal brain tissue. In this study, gold nanoparticles (GNPs) of size ranging from 5 to 90 nm are synthesized to assess the optimal size of nanocarriers that achieves maximum brain accumulation after the treatment of RI-BK. The ability of the GNPs to cross the BBTB is tested in a rat C6 glioma tumor model. The results of inductively coupled plasma-mass spectrometry and transmission electron microscopy indicate that GNPs with size of 70 nm achieve maximum permeability to the glioma. The present study supports the conclusion that RI-BK can enhance the permeability of BBTB and provides fundamental information for further development of nanomedicines or nanoprobes for glioma therapy.

Unexpectedly Enhanced Solubility of Aromatic Amino Acids and Peptides in an Aqueous Solution of Divalent Transition-Metal Cations.

We experimentally observed considerable solubility of tryptophan (Trp) in a CuCl_{2} aqueous solution, which could reach 2-5 times the solubility of Trp in pure water. Theoretical studies show that the strong cation-π interaction between Cu^{2+} and the aromatic ring in Trp modifies the electronic distribution of the aromatic ring to enhance significantly the water affinity of Trp. Similar solubility enhancement has also been observed for other divalent transition-metal cations (e.g., Zn^{2+} and Ni^{2+}), another aromatic amino acid (phenylalanine), and three aromatic peptides (Trp-Phe, Phe-Phe, and Trp-Ala-Phe).

Maize Leaf Disease Recognition Based on Improved Convolutional Neural Network ShuffleNetV2.

The occurrence of maize diseases is frequent but challenging to manage. Traditional identification methods have low accuracy and complex model structures with numerous parameters, making them difficult to implement on mobile devices. To address these challenges, this paper proposes a corn leaf disease recognition model SNMPF based on convolutional neural network ShuffleNetV2. In the down-sampling module of the ShuffleNet model, the max pooling layer replaces the deep convolutional layer to perform down-sampling. This improvement helps to extract key features from images, reduce the overfitting of the model, and improve the model's generalization ability. In addition, to enhance the model's ability to express features in complex backgrounds, the Sim AM attention mechanism was introduced. This mechanism enables the model to adaptively adjust focus and pay more attention to local discriminative features. The results on a maize disease image dataset demonstrate that the SNMPF model achieves a recognition accuracy of 98.40%, representing a 4.1 percentage point improvement over the original model, while its size is only 1.56 MB. Compared with existing convolutional neural network models such as EfficientNet, MobileViT, EfficientNetV2, RegNet, and DenseNet, this model offers higher accuracy and a more compact size. As a result, it can automatically detect and classify maize leaf diseases under natural field conditions, boasting high-precision recognition capabilities. Its accurate identification results provide scientific guidance for preventing corn leaf disease and promote the development of precision agriculture.

Construction of an abnormal glycosylation risk model and its application in predicting the prognosis of patients with head and neck cancer.

Head and neck squamous cell carcinoma (HNSCC) is the most common malignant tumor of the head and neck, and the incidence rate is increasing year by year. Protein post-translational modification, recognized as a pivotal and extensive form of protein modification, has been established to possess a profound association with tumor occurrence and progression. This study employed bioinformatics analysis utilizing transcriptome sequencing data, patient survival data, and clinical data from HNSCC to establish predictive markers of genes associated with glycosylation as prognostic risk markers. The R procedure WGCNA was employed to construct a gene co-expression network using the gene expression profile and clinical characteristics of HNSCC samples. Multiple Cox Proportional Hazards Regression Model (Cox regression) and LASSO analysis were conducted to identify the key genes exhibiting the strongest association with prognosis. A risk score, known as the glycosylation-related genes risk score (GLRS), was subsequently formulated utilizing the aforementioned core genes. This scoring system facilitated the classification of samples into high-risk and low-risk categories, thereby enabling the prediction of patient prognosis. The association between GLRS and clinical variables was examined through both univariate and multivariate Cox regression analysis. The validation of six core genes was accomplished using quantitative real-time polymerase chain reaction (qRT-PCR). The findings demonstrated noteworthy variations in risk scores among subgroups, thereby affirming the efficacy of GLRS in prognosticating patient outcomes. Furthermore, a correlation has been observed between the risk-scoring model and immune infiltration. Moreover, significant disparities exist in the expression levels of diverse immune checkpoints, epithelial-mesenchymal transition genes, and angiogenic factors between the high and low-risk groups.

Effects of glycine 64 substitutions in RNA-dependent RNA polymerase on ribavirin sensitivity and pathogenicity of coxsackievirus A6.

Hand, foot, and mouth disease (HFMD) caused by a group of enteroviruses is a global public health problem. In recent years, coxsackievirus A6 (CVA6) has emerged as an important HFMD agent. Previous studies have shown that mutations of glycine 64 in RNA-dependent RNA polymerase (3D polymerase), which is central to viral replication, cause phenotypic changes such as ribavirin resistance, increased replication fidelity, and virulence attenuation in poliovirus and enterovirus A71. In this study, we constructed CVA6 mutants with G64R, G64S, and G64T substitutions by site-directed mutagenesis in full-length cDNA of an infectious CVA6 strain cloned in pcDNA3.1. Viral RNA was obtained by in vitro transcription, and the rescued virus strains were propagated in RD cells. Sequencing after six passages revealed that G64S and G64T mutations were stably inherited, whereas G64R was genetically unstable and reversed to the wild type. Comparison of the biological characteristics of the wild-type and mutant CVA6 strains in an in vivo model (one-day-old ICR mice) revealed that the pathogenicity of CVA6-G64S and CVA6-G64T was significantly reduced compared to wild-type CVA6. In vitro experiments indicated the mutant CVA6-G64S and CVA6-G64T strains had increased resistance to 0.8 mM ribavirin and a decreased replication rate in the presence of 0.8 mM guanidine hydrochloride. Our results show that mutation of residue 64 reduces CVA6 susceptibility to ribavirin and increases CVA6 susceptibility to guanidine hydrochloride, together with increased replication fidelity and attenuated viral pathogenicity, thus laying a foundation for the development of safe and effective live attenuated CVA6 vaccine.

Synergetic association between coxsackievirus A16 genotype evolution and recombinant form shifts.

Coxsackievirus A16 (CVA16) is a major pathogen that causes hand, foot, and mouth disease (HFMD). The recombination form (RF) shifts and global transmission dynamics of CVA16 remain unknown. In this retrospective study, global sequences of CVA16 were retrieved from the GenBank database and analyzed using comprehensive phylogenetic inference, RF surveys, and population structure. A total of 1,663 sequences were collected, forming a 442-sequences dataset for VP1 coding region analysis and a 345-sequences dataset for RF identification. Based on the VP1 coding region used for serotyping, three genotypes (A, B, and D), two subgenotypes of genotype B (B1 and B2), and three clusters of subgenotype B1 (B1a, B1b, and B1c) were identified. Cluster B1b has dominated the global epidemics, B2 disappeared in 2000, and D is an emerging genotype dating back to August 2002. Globally, four oscillation phases of CVA16 evolution, with a peak in 2013, and three migration pathways were identified. Europe, China, and Japan have served as the seeds for the global transmission of CVA16. Based on the 3D coding region of the RFs, five clusters of RFs (RF-A to -E) were identified. The shift in RFs from RF-B and RF-C to RF-D was accompanied by a change in genotype from B2 to B1a and B1c and then to B1b. In conclusion, the evolution and population dynamics of CVA16, especially the coevolution of 3D and VP1 genes, revealed that genotype evolution and RF replacement were synergistic rather than stochastic.

Identification of leaf diseases in field crops based on improved ShuffleNetV2.

Rapid and accurate identification and timely protection of crop disease is of great importance for ensuring crop yields. Aiming at the problems of large model parameters of existing crop disease recognition methods and low recognition accuracy in the complex background of the field, we propose a lightweight crop leaf disease recognition model based on improved ShuffleNetV2. First, the repetition number and the number of output channels of the basic module of the ShuffleNetV2 model are redesigned to reduce the model parameters to make the model more lightweight while ensuring the accuracy of the model. Second, the residual structure is introduced in the basic feature extraction module to solve the gradient vanishing problem and enable the model to learn more complex feature representations. Then, parallel paths were added to the mechanism of the efficient channel attention (ECA) module, and the weights of different paths were adaptively updated by learnable parameters, and then the efficient dual channel attention (EDCA) module was proposed, which was embedded into the ShuffleNetV2 to improve the cross-channel interaction capability of the model. Finally, a multi-scale shallow feature extraction module and a multi-scale deep feature extraction module were introduced to improve the model's ability to extract lesions at different scales. Based on the above improvements, a lightweight crop leaf disease recognition model REM-ShuffleNetV2 was proposed. Experiments results show that the accuracy and F1 score of the REM-ShuffleNetV2 model on the self-constructed field crop leaf disease dataset are 96.72% and 96.62%, which are 3.88% and 4.37% higher than that of the ShuffleNetV2 model; and the number of model parameters is 4.40M, which is 9.65% less than that of the original model. Compared with classic networks such as DenseNet121, EfficientNet, and MobileNetV3, the REM-ShuffleNetV2 model not only has higher recognition accuracy but also has fewer model parameters. The REM-ShuffleNetV2 model proposed in this study can achieve accurate identification of crop leaf disease in complex field backgrounds, and the model is small, which is convenient to deploy to the mobile end, and provides a reference for intelligent diagnosis of crop leaf disease.

Evolution, recombination and geographic spreading of global Coxsackievirus A6.

BACKGROUND: The increasing incidence of hand, foot, and mouth disease (HFMD) associated with Coxsackievirus A6 (CVA6) has become a very significant public health problem. The aim of this study is to investigate the recombination, geographic transmission, and evolutionary characteristics of the global CVA6. METHODS: From 2019 to 2022, 73 full-length CVA6 sequences were obtained from HFMD patients in China and analyzed in combination with 1032 published whole genome sequences. Based on this dataset, the phylogenetic features, recombinant diversity, Bayesian phylodynamic characteristics, and key amino acid variations in CVA6 were analyzed. RESULTS: The four genotypes of CVA6, A, D, E, and F, are divided into 24 recombinant forms (RFs, RF-A - RF-X) based on differences in the P3 coding region. The eastern China region plays a key role in the dissemination of CVA6 in China. VP1-137 and VP1-138 are located in the DE loop on the surface of the CVA6 VP1 protein, with the former being a highly variable site and the latter having more non-synonymous substitutions. CONCLUSIONS: Based on whole genome sequences, this study contributes to the CVA6 monitoring, early warning, and the pathogenic mechanism by studying recombination diversity, geographical transmission characteristics, and the variation of important amino acid sites.

Molecular switch for tuning ions across nanopores by an external electric field.

Active control of ion transport in nanoscale channels is attracting increasing attention. Recently, experimental and theoretical results have verified that depending on the charged surface of nanopores, the solution inside nanopores can contain either negative or positive ions, which does not happen in macroscale channels. However, the control of the surface chemistry of synthetic nanopores is difficult and the design of nanotubes with novel recognition mechanisms that regulate the ionic selectivity of negative and positive charges remains a challenge. We present here a design for an ion-selective nanopore that is controllable by external charges. Our molecular dynamics simulations show that this remarkable selectivity can be switched from predominantly negative to positive ions and that the magnitude of the ionic flux can be varied by changing the distance of the external charges. The results suggest that the hydration structures around ions play a prominent role in the selectivity process, which is tuned by the external charge. These studies may be useful for developing ways to control the behavior, properties and chemical composition of liquids and provide possible technical applications for nanofluidic field effect transistors.

Coxsackievirus A6 Infection Causes Neurogenic Pathogenesis in a Neonatal Murine Model.

Coxsackievirus A6 (CVA6), a member of species A enterovirus, is associated with outbreaks of hand-foot-and-mouth disease and causes a large nationwide burden of disease. However, the molecular pathogenesis of CVA6 remains unclear. In the present study, we established a suckling Institute of Cancer Research (ICR) mouse infection model to explore the neural pathogenicity of CVA6. Five-day-old mice infected with CVA6 strain F219 showed lethargy and paralysis, and died 5 or 6 days after infection via IM injection. Cerebral edema and neuronal cell swelling were observed in the infected brain tissue, and we found that the CVA6 VP1 antigen could co-localize with GFAP-positive astrocytes in infected mouse brain using an immunofluorescence assay. CVA6 strain F219 can also infect human glioma (U251) cells. Transcriptome analysis of brain tissues from infected mice and infected U251 cells showed that significantly differentially expressed genes were enriched in antiviral and immune response and neurological system processes. These results indicate that CVA6 could cause neural pathogenesis and provide basic data for exploring the mechanism of how host-cell interactions affect viral replication and pathogenesis. Importance: Coxsackievirus A6 (CVA6) surpasses the two main pathogens, enterovirus 71 (EV-A71) and coxsackievirus A16 (CVA16), which are the leading pathogens causing HFMD in many provinces of China. In our study, CVA6 infection caused neurogenic pathogenesis in a neonatal murine model, manifesting as cerebral edema and neuronal cell swelling, CVA6 VP1 antigen could co-localize with GFAP-positive astrocytes in the infected mouse brain. Based on CVA6-infected brain tissue and U251 cell transcriptome analysis, we found upregulated antiviral and immune response-related genes such as Zbp1, Usp18, Oas2, Irf7, Ddx60, Ifit3, Ddx58, and Isg15, while the neurological system process-related genes were downregulated, including Fcrls, Ebnrb, Cdk1, and Anxa5.