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Rbfox proteins control alternative splicing and posttranscriptional regulation in mammalian brain and are implicated in neurological disease. These proteins recognize the RNA sequence (U)GCAUG, but their structures and diverse roles imply a variety of protein-protein interactions. We find that nuclear Rbfox proteins are bound within a large assembly of splicing regulators (LASR), a multimeric complex containing the proteins hnRNP M, hnRNP H, hnRNP C, Matrin3, NF110/NFAR-2, NF45, and DDX5, all approximately equimolar to Rbfox. We show that splicing repression mediated by hnRNP M is stimulated by Rbfox. Virtually all the intron-bound Rbfox is associated with LASR, and hnRNP M motifs are enriched adjacent to Rbfox crosslinking sites in vivo. These findings demonstrate that Rbfox proteins bind RNA with a defined set of cofactors and affect a broader set of exons than previously recognized. The function of this multimeric LASR complex has implications for deciphering the regulatory codes controlling splicing networks.
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Splicing de RNA , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Éxons , Células HEK293 , Humanos , Íntrons , Camundongos , Complexos Multiproteicos/metabolismo , Precursores de RNA/metabolismoRESUMO
The MYC proto-oncogene contributes to the pathogenesis of more than half of human cancers. Malignant transformation by MYC transcriptionally up-regulates the core pre-mRNA splicing machinery and causes misregulation of alternative splicing. However, our understanding of how splicing changes are directed by MYC is limited. We performed a signaling pathway-guided splicing analysis to identify MYC-dependent splicing events. These included an HRAS cassette exon repressed by MYC across multiple tumor types. To molecularly dissect the regulation of this HRAS exon, we used antisense oligonucleotide tiling to identify splicing enhancers and silencers in its flanking introns. RNA-binding motif prediction indicated multiple binding sites for hnRNP H and hnRNP F within these cis-regulatory elements. Using siRNA knockdown and cDNA expression, we found that both hnRNP H and F activate the HRAS cassette exon. Mutagenesis and targeted RNA immunoprecipitation implicate two downstream G-rich elements in this splicing activation. Analyses of ENCODE RNA-seq datasets confirmed hnRNP H regulation of HRAS splicing. Analyses of RNA-seq datasets across multiple cancers showed a negative correlation of HNRNPH gene expression with MYC hallmark enrichment, consistent with the effect of hnRNP H on HRAS splicing. Interestingly, HNRNPF expression showed a positive correlation with MYC hallmarks and thus was not consistent with the observed effects of hnRNP F. Loss of hnRNP H/F altered cell cycle progression and induced apoptosis in the PC3 prostate cancer cell line. Collectively, our results reveal mechanisms for MYC-dependent regulation of splicing and point to possible therapeutic targets in prostate cancers.
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Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H , Neoplasias da Próstata , Masculino , Humanos , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA/genética , Proteínas de Ligação a RNA/metabolismo , Éxons/genética , Processamento Alternativo/genética , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismoRESUMO
Alternative splicing (AS) is prevalent in cancer, generating an extensive but largely unexplored repertoire of novel immunotherapy targets. We describe Isoform peptides from RNA splicing for Immunotherapy target Screening (IRIS), a computational platform capable of discovering AS-derived tumor antigens (TAs) for T cell receptor (TCR) and chimeric antigen receptor T cell (CAR-T) therapies. IRIS leverages large-scale tumor and normal transcriptome data and incorporates multiple screening approaches to discover AS-derived TAs with tumor-associated or tumor-specific expression. In a proof-of-concept analysis integrating transcriptomics and immunopeptidomics data, we showed that hundreds of IRIS-predicted TCR targets are presented by human leukocyte antigen (HLA) molecules. We applied IRIS to RNA-seq data of neuroendocrine prostate cancer (NEPC). From 2,939 NEPC-associated AS events, IRIS predicted 1,651 epitopes from 808 events as potential TCR targets for two common HLA types (A*02:01 and A*03:01). A more stringent screening test prioritized 48 epitopes from 20 events with "neoantigen-like" NEPC-specific expression. Predicted epitopes are often encoded by microexons of ≤30 nucleotides. To validate the immunogenicity and T cell recognition of IRIS-predicted TCR epitopes, we performed in vitro T cell priming in combination with single-cell TCR sequencing. Seven TCRs transduced into human peripheral blood mononuclear cells (PBMCs) showed high activity against individual IRIS-predicted epitopes, providing strong evidence of isolated TCRs reactive to AS-derived peptides. One selected TCR showed efficient cytotoxicity against target cells expressing the target peptide. Our study illustrates the contribution of AS to the TA repertoire of cancer cells and demonstrates the utility of IRIS for discovering AS-derived TAs and expanding cancer immunotherapies.
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Neoplasias , Precursores de RNA , Masculino , Humanos , Precursores de RNA/metabolismo , Processamento Alternativo , Leucócitos Mononucleares/metabolismo , Receptores de Antígenos de Linfócitos T , Epitopos de Linfócito T , Imunoterapia , Antígenos de Neoplasias , Peptídeos/metabolismo , Neoplasias/genética , Neoplasias/terapiaRESUMO
China is home to the second largest population of children and adolescents in the world. Yet demographic shifts mean that the government must manage the challenge of fewer children with the needs of an ageing population, while considering the delicate tension between economic growth and environmental sustainability. We mapped the health problems and risks of contemporary school-aged children and adolescents in China against current national health policies. We involved multidisciplinary experts, including young people, with the aim of identifying actionable strategies and specific recommendations to promote child and adolescent health and wellbeing. Notwithstanding major improvements in their health over the past few decades, contemporary Chinese children and adolescents face distinct social challenges, including high academic pressures and youth unemployment, and new health concerns including obesity, mental health issues, and sexually transmitted infections. Inequality by gender, geography, and ethnicity remains a feature of health risks and outcomes. We identified a mismatch between current health determinants, risks and outcomes, and government policies. To promote the health of children and adolescents in China, we recommend a set of strategies that target government-led initiatives across the health, education, and community sectors, which aim to build supportive and responsive families, safe communities, and engaging and respectful learning environments. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.
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Política de Saúde , Adolescente , Criança , Feminino , Humanos , Masculino , Saúde do Adolescente , Saúde da Criança , China , População do Leste Asiático , Necessidades e Demandas de Serviços de SaúdeRESUMO
Genomic variants affecting pre-messenger RNA splicing and its regulation are known to underlie many rare genetic diseases. However, common workflows for genetic diagnosis and clinical variant interpretation frequently overlook splice-altering variants. To better serve patient populations and advance biomedical knowledge, it has become increasingly important to develop and refine approaches for detecting and interpreting pathogenic splicing variants. In this review, we will summarize a few recent developments and challenges in using RNA sequencing technologies for rare disease investigation. Moreover, we will discuss how recent computational splicing prediction tools have emerged as complementary approaches for revealing disease-causing variants underlying splicing defects. We speculate that continuous improvements to sequencing technologies and predictive modeling will not only expand our understanding of splicing regulation but also bring us closer to filling the diagnostic gap for rare disease patients.
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Doenças Raras , Transcriptoma , Humanos , Doenças Raras/diagnóstico , Doenças Raras/genética , Splicing de RNA , Proteínas , Aprendizado de Máquina , MutaçãoRESUMO
Genomic recombination is an important driving force for viral evolution, and recombination events have been reported for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the Coronavirus Disease 2019 pandemic, which significantly alter viral infectivity and transmissibility. However, it is difficult to identify viral recombination, especially for low-divergence viruses such as SARS-CoV-2, since it is hard to distinguish recombination from in situ mutation. Herein, we applied information theory to viral recombination analysis and developed VirusRecom, a program for efficiently screening recombination events on viral genome. In principle, we considered a recombination event as a transmission process of ``information'' and introduced weighted information content (WIC) to quantify the contribution of recombination to a certain region on viral genome; then, we identified the recombination regions by comparing WICs of different regions. In the benchmark using simulated data, VirusRecom showed a good balance between precision and recall compared to two competing tools, RDP5 and 3SEQ. In the detection of SARS-CoV-2 XE, XD and XF recombinants, VirusRecom providing more accurate positions of recombination regions than RDP5 and 3SEQ. In addition, we encapsulated the VirusRecom program into a command-line-interface software for convenient operation by users. In summary, we developed a novel approach based on information theory to identify viral recombination within highly similar sequences, providing a useful tool for monitoring viral evolution and epidemic control.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Teoria da Informação , Filogenia , Recombinação GenéticaRESUMO
Fibers, originating from nature and mastered by human, have woven their way throughout the entire history of human civilization. Recent developments in semiconducting polymer materials have further endowed fibers and textiles with various electronic functions, which are attractive in applications such as information interfacing, personalized medicine, and clean energy. Owing to their ability to be easily integrated into daily life, soft fiber electronics based on semiconducting polymers have gained popularity recently for wearable and implantable applications. Herein, we present a review of the previous and current progress in semiconducting polymer-based fiber electronics, particularly focusing on smart-wearable and implantable areas. First, we provide a brief overview of semiconducting polymers from the viewpoint of materials based on the basic concepts and functionality requirements of different devices. Then we analyze the existing applications and associated devices such as information interfaces, healthcare and medicine, and energy conversion and storage. The working principle and performance of semiconducting polymer-based fiber devices are summarized. Furthermore, we focus on the fabrication techniques of fiber devices. Based on the continuous fabrication of one-dimensional fiber and yarn, we introduce two- and three-dimensional fabric fabricating methods. Finally, we review challenges and relevant perspectives and potential solutions to address the related problems.
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The efficient interconversion of chemicals and electricity through electrocatalytic processes is central to many renewable-energy initiatives. The sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER)1-4 has long posed one of the biggest challenges in this field, and electrocatalysts based on expensive platinum-group metals are often required to improve the activity and durability of these reactions. The use of alloying5-7, surface strain8-11 and optimized coordination environments12 has resulted in platinum-based nanocrystals that enable very high ORR activities in acidic media; however, improving the activity of this reaction in alkaline environments remains challenging because of the difficulty in achieving optimized oxygen binding strength on platinum-group metals in the presence of hydroxide. Here we show that PdMo bimetallene-a palladium-molybdenum alloy in the form of a highly curved and sub-nanometre-thick metal nanosheet-is an efficient and stable electrocatalyst for the ORR and the OER in alkaline electrolytes, and shows promising performance as a cathode in Zn-air and Li-air batteries. The thin-sheet structure of PdMo bimetallene enables a large electrochemically active surface area (138.7 square metres per gram of palladium) as well as high atomic utilization, resulting in a mass activity towards the ORR of 16.37 amperes per milligram of palladium at 0.9 volts versus the reversible hydrogen electrode in alkaline electrolytes. This mass activity is 78 times and 327 times higher than those of commercial Pt/C and Pd/C catalysts, respectively, and shows little decay after 30,000 potential cycles. Density functional theory calculations reveal that the alloying effect, the strain effect due to the curved geometry, and the quantum size effect due to the thinness of the sheets tune the electronic structure of the system for optimized oxygen binding. Given the properties and the structure-activity relationships of PdMo metallene, we suggest that other metallene materials could show great promise in energy electrocatalysis.
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BACKGROUND: An accelerated epidemiological transition, spurred by economic development and urbanization, has led to a rapid transformation of the disease spectrum. However, this transition has resulted in a divergent change in the burden of infectious diseases between urban and rural areas. The objective of our study was to evaluate the long-term urban-rural disparities in infectious diseases among children, adolescents, and youths in China, while also examining the specific diseases driving these disparities. METHODS AND FINDINGS: This observational study examined data on 43 notifiable infectious diseases from 8,442,956 cases from individuals aged 4 to 24 years, with 4,487,043 cases in urban areas and 3,955,913 in rural areas. The data from 2013 to 2021 were obtained from China's Notifiable Infectious Disease Surveillance System. The 43 infectious diseases were categorized into 7 categories: vaccine-preventable, bacterial, gastrointestinal and enterovirus, sexually transmitted and bloodborne, vectorborne, zoonotic, and quarantinable diseases. The calculation of infectious disease incidence was stratified by urban and rural areas. We used the index of incidence rate ratio (IRR), calculated by dividing the urban incidence rate by the rural incidence rate for each disease category, to assess the urban-rural disparity. During the nine-year study period, most notifiable infectious diseases in both urban and rural areas exhibited either a decreased or stable pattern. However, a significant and progressively widening urban-rural disparity in notifiable infectious diseases was observed. Children, adolescents, and youths in urban areas experienced a higher average yearly incidence compared to their rural counterparts, with rates of 439 per 100,000 compared to 211 per 100,000, respectively (IRR: 2.078, 95% CI [2.075, 2.081]; p < 0.001). From 2013 to 2021, this disparity was primarily driven by higher incidences of pertussis (IRR: 1.782, 95% CI [1.705, 1.862]; p < 0.001) and seasonal influenza (IRR: 3.213, 95% CI [3.205, 3.220]; p < 0.001) among vaccine-preventable diseases, tuberculosis (IRR: 1.011, 95% CI [1.006, 1.015]; p < 0.001), and scarlet fever (IRR: 2.942, 95% CI [2.918, 2.966]; p < 0.001) among bacterial diseases, infectious diarrhea (IRR: 1.932, 95% CI [1.924, 1.939]; p < 0.001), and hand, foot, and mouth disease (IRR: 2.501, 95% CI [2.491, 2.510]; p < 0.001) among gastrointestinal and enterovirus diseases, dengue (IRR: 11.952, 95% CI [11.313, 12.628]; p < 0.001) among vectorborne diseases, and 4 sexually transmitted and bloodborne diseases (syphilis: IRR 1.743, 95% CI [1.731, 1.755], p < 0.001; gonorrhea: IRR 2.658, 95% CI [2.635, 2.682], p < 0.001; HIV/AIDS: IRR 2.269, 95% CI [2.239, 2.299], p < 0.001; hepatitis C: IRR 1.540, 95% CI [1.506, 1.575], p < 0.001), but was partially offset by lower incidences of most zoonotic and quarantinable diseases in urban areas (for example, brucellosis among zoonotic: IRR 0.516, 95% CI [0.498, 0.534], p < 0.001; hemorrhagic fever among quarantinable: IRR 0.930, 95% CI [0.881, 0.981], p = 0.008). Additionally, the overall urban-rural disparity was particularly pronounced in the middle (IRR: 1.704, 95% CI [1.699, 1.708]; p < 0.001) and northeastern regions (IRR: 1.713, 95% CI [1.700, 1.726]; p < 0.001) of China. A primary limitation of our study is that the incidence was calculated based on annual average population data without accounting for population mobility. CONCLUSIONS: A significant urban-rural disparity in notifiable infectious diseases among children, adolescents, and youths was evident from our study. The burden in urban areas exceeded that in rural areas by more than 2-fold, and this gap appears to be widening, particularly influenced by tuberculosis, scarlet fever, infectious diarrhea, and typhus. These findings underscore the urgent need for interventions to mitigate infectious diseases and address the growing urban-rural disparity.
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Doenças Transmissíveis , Escarlatina , Tuberculose , Criança , Adolescente , Humanos , Doenças Transmissíveis/epidemiologia , China/epidemiologia , DiarreiaRESUMO
Mitochondrial therapy is a promising new strategy that offers the potential to achieve precise disease diagnosis or maximum therapeutic response. However, versatile mitochondrial theranostic platforms that integrate biomarker detection and therapy have rarely been exploited. Here, we report a charge-reversal nanomedicine activated by an acidic microenvironment for mitochondrial microRNA (mitomiR) detection and ion-interference therapy. The transporter liposome (DD-DC) was constructed from a pH-responsive polymer and a positively charged phospholipid, encapsulating NaCl nanoparticles with coloading of the aggregation-induced emission (AIE) fluorogens AIEgen-DNA/G-quadruplexes precursor and brequinar (NAB@DD-DC). The negatively charged nanomedicine ensured good blood stability and high tumor accumulation, while the charge-reversal to positive in response to the acidic pH in the tumor microenvironment (TME) and lysosomes enhanced the uptake by tumor cells and lysosome escape, achieving accumulation in mitochondria. The subsequently released Na+ in mitochondria not only contributed to the formation of mitomiR-494 induced G-quadruplexes for AIE imaging diagnosis but also led to an osmolarity surge that was enhanced by brequinar to achieve effective ion-interference therapy.
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Compostos de Bifenilo , Quadruplex G , MicroRNAs , Nanopartículas , Neoplasias , Quinaldinas , Humanos , Cloreto de Sódio , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Mitocôndrias , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
Microdevices that offer hyperglycemia monitoring and controllable drug delivery are urgently needed for daily diabetes management. Herein, a theranostic separable double-layer microneedle (DLMN) patch consisting of a swellable GelMA supporting base layer for glycemia sensing and a phase-change material (PCM) arrowhead layer for hyperglycemia regulation has been fabricated. The Cu-TCPP(Fe)/glucose oxidase composite and 3,3',5,5'-tetramethylbenzidine coembedded in the supporting base layer permit a visible color shift at the base surface in the presence of glucose via a cascade reaction, allowing for the in situ detection of glucose in interstitial fluid. The PCM arrowhead layer is encapsulated with water monodispersity melanin nanoparticles from Sepia officinalis and metformin that is imparted with a near-infrared ray photothermal response feature, which is beneficial to the controllable release of metformin for suppression of hyperglycemia. By applying the DLMN patch to the streptozotocin-induced type 2 diabetic Sprague-Dawley rat model, the results demonstrated that it can effectively extract dermal interstitial fluid, read out glucose levels, and regulate hyperglycemia. This DLMN-integrated portable colorimetric sensor and self-regulated glucose level hold great promise for daily diabetes management.
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Steps of mRNA maturation are important gene regulatory events that occur in distinct cellular locations. However, transcriptomic analyses often lose information on the subcellular distribution of processed and unprocessed transcripts. We generated extensive RNA-seq data sets to track mRNA maturation across subcellular locations in mouse embryonic stem cells, neuronal progenitor cells, and postmitotic neurons. We find disparate patterns of RNA enrichment between the cytoplasmic, nucleoplasmic, and chromatin fractions, with some genes maintaining more polyadenylated RNA in chromatin than in the cytoplasm. We bioinformatically defined four regulatory groups for intron retention, including complete cotranscriptional splicing, complete intron retention in the cytoplasmic RNA, and two intron groups present in nuclear and chromatin transcripts but fully excised in cytoplasm. We found that introns switch their regulatory group between cell types, including neuronally excised introns repressed by polypyrimidine track binding protein 1 (PTBP1). Transcripts for the neuronal gamma-aminobutyric acid (GABA) B receptor, 1 (Gabbr1) are highly expressed in mESCs but are absent from the cytoplasm. Instead, incompletely spliced Gabbr1 RNA remains sequestered on chromatin, where it is bound by PTBP1, similar to certain long noncoding RNAs. Upon neuronal differentiation, Gabbr1 RNA becomes fully processed and exported for translation. Thus, splicing repression and chromatin anchoring of RNA combine to allow posttranscriptional regulation of Gabbr1 over development. For this and other genes, polyadenylated RNA abundance does not indicate functional gene expression. Our data sets provide a rich resource for analyzing many other aspects of mRNA maturation in subcellular locations and across development.
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Precursores de RNA , Splicing de RNA , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , Genes Controladores do Desenvolvimento , Íntrons/genética , Camundongos , Precursores de RNA/genética , Precursores de RNA/metabolismoRESUMO
Virus-encoded small RNAs (vsRNA) have been reported to play an important role in viral infection. Unfortunately, there is still a lack of an effective method for vsRNA identification. Herein, we presented vsRNAfinder, a de novo method for identifying high-confidence vsRNAs from small RNA-Seq (sRNA-Seq) data based on peak calling and Poisson distribution and is publicly available at https://github.com/ZenaCai/vsRNAfinder. vsRNAfinder outperformed two widely used methods namely miRDeep2 and ShortStack in identifying viral miRNAs with a significantly improved sensitivity. It can also be used to identify sRNAs in animals and plants with similar performance to miRDeep2 and ShortStack. vsRNAfinder would greatly facilitate effective identification of vsRNAs from sRNA-Seq data.
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MicroRNAs , Animais , RNA-Seq , MicroRNAs/genética , Análise de Sequência de RNA/métodosRESUMO
To investigate the progress of disparities in human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), gonorrhea, and syphilis among children and adolescents aged 6-22 years in China during 2013-2021. A total of 614 325 cases data were extracted from the Chinese Information System for Infectious Diseases Control and Prevention during 2013-2021. Puberty health education data were drew from the Student Health Surveillance in 2021. Disparity patterns and average annual percentage changes (AAPCs) in sexually transmitted infections (STIs) incidence or new cases in China were examined using descriptive statistics and joinpoint regression. The incidence across 345 cities was stratified by gross domestic product (GDP). Between 2013 and 2021, there were 614 325 reported cases of HIV/AIDS, gonorrhea, and syphilis among children and adolescents aged 6-22, with an annual average incidence of 24.0967 per 100 000. The expansion of HIV/AIDS has halted, yet the surge in gonorrhea and syphilis remains notably pronounced. The ratio of male to female AIDS incidence increased from 2.75 (2.60, 2.90) to 7.13 (6.68, 7.62), but that of syphilis changed from 0.33 (0.32, 0.34) to 0.56 (0.55, 0.57). Students and out-of-school individuals aged 13-15 experienced a notably high increase in STI cases, surpassing other age groups, with an average annual percentage increase of 29.2% and 26.3%, respectively. Nonstudents consistently had a higher incidence rate than students, with an IRR reaching 31.80 (31.24, 32.37) in 2021. A noticeable clustering pattern of new cases emerged in the southeastern region of the Heihe-Tengchong line, extending inland from the coastal areas. Districts and counties with lower rates of puberty sexual health education tended to have higher average STI incidence rates. At the prefecture and city levels, there was a noticeable upward trend on average STI incidence rates in cities with per capita GDPs. Strategies to address those disparities include promoting equitable health education, and widespread sexual health education, particularly in areas with limited access to education and experiencing rapid economic development. The effectiveness of sexual health education intervention needs to be further evaluated in well-designed studies.
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Gonorreia , Infecções Sexualmente Transmissíveis , Humanos , Adolescente , Masculino , Feminino , China/epidemiologia , Incidência , Criança , Adulto Jovem , Gonorreia/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções por HIV/epidemiologia , Sífilis/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Monitoramento EpidemiológicoRESUMO
Tetraparvovirus is an emerging parvovirus infecting a variety of mammals and humans, and associated with human diseases including severe acute respiratory infection and acute encephalitis syndrome. In the present study, a Tetraparvovirus ungulate 1 (formerly known as bovine hokovirus) strain HNU-CBY-2023 was identified and characterized from diseased Chinese Simmental from Hunan province, China. The nearly complete genome of HNU-CBY-2023 is 5346 nt in size and showed genomic identities of 85-95.5% to the known Tetraparvovirus ungulate 1 strains from GenBank, indicating a rather genetic variation. Phylogenetic and genetic divergence analyses indicated that Tetraparvovirus ungulate 1 could be divided into two genotypes (I and II), and HNU-CBY-2023 was clustered into genotype II. This study, for the first time, identified Tetraparvovirus ungulate 1 from domestic cattle from mainland China, which will be helpful to understand the prevalence and genetic diversity of Tetraparvovirus ungulate 1.
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Doenças dos Bovinos , Variação Genética , Genoma Viral , Genótipo , Infecções por Parvoviridae , Filogenia , Animais , Bovinos , China , Doenças dos Bovinos/virologia , Doenças dos Bovinos/epidemiologia , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Infecções por Parvoviridae/epidemiologia , Genoma Viral/genética , Parvovirinae/genética , Parvovirinae/isolamento & purificação , Parvovirinae/classificação , Análise de Sequência de DNA , DNA Viral/genética , População do Leste AsiáticoRESUMO
In nature, selective interactions between chiral amino acids and crystals are important for the formation of chiral biominerals and provide insight into the mysterious origin of homochirality. Here, we show that chiral amino acids with different hydrophilicities/hydrophobicities exhibit different chiral selectivity preferences in the dynamically growing gypsum [001] steps. Hydrophilic amino acids show a chiral selectivity preference for their d-isomers, whereas hydrophobic amino acids prefer their l-isomers. These differences in chiral recognition can be attributed to the different stereochemical matching between the hydrophilic and hydrophobic amino acids on the [001] steps of growing gypsum. These different chiral selectivities resulting from the amino acid hydrophilicity/hydrophobicity are confirmed by the experimental crystallization investigations from nano regulation on dynamic steps, to microscopic modification of gypsum morphology, and to macroscopic precipitation. Furthermore, as the hydrophilicity of amino acids increases, the disparity in chiral selection rises; conversely, the increase in the hydrophobicity of amino acids results in a decline in chiral selection. These insights improve our understanding of the interaction mechanism between amino acids and crystals and provide insights into the formation process of chiral biominerals and the origin of homochirality in nature.
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Polyvinyl chloride (PVC) waste plastic is a typical solid waste. In this paper, the dechlorination and carbonization behavior of PVC in ethanol-water/water system under different process parameters (temperature, residence time, solid-liquid ratio) was studied, and hydrothermal carbon was characterized by SEM, elemental analysis, TG-DTG, XPS, Py-GC/MS. The results show that temperature is the key to the hydrothermal dechlorination of PVC, and the dechlorination efficiency of PVC is the highest by parameter optimization (220°C-90 min-10% S/D-80% E/D), which can reach 96.33 %. With the removal of Cl, the surface of the PVC matrix changed from full and smooth flocculent to honeycomb with uniform pore size distribution. Thermogravimetric analysis shows that the combustion of hydrochar can be divided into three stages: HCl precipitation and volatile combustion, semi-coke and coke combustion, and fixed carbon combustion. The combustion parameters and kinetic parameters of hydrochar were measured, and it was found that the hydrothermal carbonization of PVC at higher temperatures and ethanol-water ratio could improve the combustion performance of hydrochar. The highest calorific value can reach 36.68 MJ/mol. Py-GC/MS analyzed the distribution of the pyrolysis products, and alkylbenzene and aliphatic were the main products of pyrolysis. The structural analysis of hydrochar showed that C-C and CC accounted for the largest proportion, accompanied by a small amount of C-O and CO and trace C-Cl. The possible reaction mechanism of the hydrothermal carbonization of PVC was analyzed based on the distribution of functional groups and compound composition. This work provides an effective and sustainable method for the recycling of refractory chlorinated plastics.
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Coque , Cloreto de Polivinila , Cloreto de Polivinila/química , Água , Temperatura , CarbonoRESUMO
The Yangtze River Delta (YRD), one of the most economically developed and industrialized regions in China, is confronted with challenges arising from rapid urbanization, particularly environmental pollution. The collection of surface water and sediment samples from forty-nine sites in the YRD was conducted to analyze 2378-substituted polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) congeners. The detected concentrations of PCDD/Fs were 0-5.3 pg TEQ/L in water and 0.12-1493 pg TEQ/g dw in sediment. The PCDD/Fs contamination in the sediment was widespread in the YRD. There were variations in the congener characteristics of PCDD/Fs in surface water and sediment. The proportion of OCDD was significantly lower in surface water samples compared to sediment, while the less chlorine-substituted homologs were found in larger proportions. To understand the partitioning and behavior of dioxins within the water-sediment system, we calculated the organic carbon normalized partition coefficients and fugacity fraction (ff) of PCDD/F congeners. The results revealed that the PCDD/Fs had not attained a state of distributional equilibrium, and the non-specific hydrophobic effect seemed minimally influential on their partitioning between sediment and water. The average ff values, which varied between 0.06 and 0.63, indicated differing migration directions for the PCDD/F congeners. Source identification analysis provided evidence that the dioxins in the river water were primarily attributed to industrial thermal processes. Iron and steel smelting, along with pesticide production and use, were likely responsible for the sediment contamination. This comprehensive analysis underscores the complex nature of PCDD/Fs pollution in the YRD and highlights the necessity for targeted environmental management strategies.
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Dibenzofuranos Policlorados , Monitoramento Ambiental , Sedimentos Geológicos , Dibenzodioxinas Policloradas , Rios , Poluentes Químicos da Água , China , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Dibenzodioxinas Policloradas/análise , Poluentes Químicos da Água/análise , Dibenzofuranos Policlorados/análise , Rios/química , Benzofuranos/análiseRESUMO
The performance of Electro-Fenton (EF) cathode materials is primarily assessed by H2O2 yield and Fe3+ reduction efficiency. This study explores the impact of pore structure in chitin-based porous carbon on EF cathode effectiveness. We fabricated mesoporous carbon (CPC-700-2) and microporous carbon (ZPC-700-3) using template and activation methods, retaining nitrogen from the precursors. CPC-700-2, with mesopores (3-5 nm), enhanced O2 diffusion and oxygen reduction, producing up to 778 mg/L of H2O2 in 90 min. ZPC-700-3, with a specific surface area of 1059.83 m2/g, facilitated electron transport and ion diffusion, achieving a Fe2+/Fe3+ conversion rate of 79.9%. EF systems employing CPC-700-2 or ZPC-700-3 as the cathode exhibited superior degradation performance, achieving 99% degradation of Rhodamine B, efficient degradation, and noticeable decolorization. This study provides a reference for the preparation of functionalized carbon cathode materials for efficient H2O2 production and effective Fe3+ reduction in EF systems.
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Although the Three Gorges Dam (TGD) is the world's largest hydroelectric dam, little is known about the spatial-temporal patterns and community assembly mechanisms of meio- and micro-eukaryotes and its two subtaxa (zooplankton and zoobenthos). This knowledge gap is particularly evident across various habitats and during different water-level periods, primarily arising from the annual regular dam regulation. To address this inquiry, we employed mitochondrial cytochrome c oxidase I (COI) gene-based environmental DNA (eDNA) metabarcoding technology to systematically analyze the biogeographic pattern of the three communities within the Three Gorges Reservoir (TGR). Our findings reveal distinct spatiotemporal characteristics and complementary patterns in the distribution of meio- and micro-eukaryotes. The three communities showed similar biogeographic patterns and assembly processes. Notably, the diversity of these three taxa gradually decreased along the river. Their communities were less shaped by stochastic processes, which gradually decreased along the longitudinal riverine-transition-lacustrine gradient. Hence, deterministic factors, such as seasonality, environmental, and spatial variables, along with species interactions, likely play a pivotal role in shaping these communities. Environmental factors primarily drive seasonal variations in these communities, while hydrological conditions, represented as spatial distance, predominantly influence spatial variations. These three communities followed the distance-decay pattern. In winter, compared to summer, both the decay and species interrelationships are more pronounced. Taken together, this study offers fresh insights into the composition and diversity patterns of meio- and micro-eukaryotes at the spatial-temporal level. It also uncovers the mechanisms behind community assembly in various environmental niches within the dam-induced river-reservoir systems. KEY POINTS: ⢠Distribution and diversity of meio- and micro-eukaryotes exhibit distinct spatiotemporal patterns in the TGR. ⢠Contribution of stochastic processes in community assembly gradually decreases along the river. ⢠Deterministic factors and species interactions shape meio- and micro-eukaryotic community.