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Poxviruses are often thought to evolve relatively slowly because they are double-stranded DNA pathogens with proofreading polymerases. However, poxviruses have highly adaptable genomes and can undergo relatively rapid genotypic and phenotypic change, as illustrated by the recent increase in human-to-human transmission of monkeypox virus. Advances in deep sequencing technologies have demonstrated standing nucleotide variation in poxvirus populations, which has been underappreciated. There is also an emerging understanding of the role genomic architectural changes play in shaping poxvirus evolution. These mechanisms include homologous and nonhomologous recombination, gene duplications, gene loss, and the acquisition of new genes through horizontal gene transfer. In this review, we discuss these evolutionary mechanisms and their potential roles for adaption to novel host species and modulating virulence.

Myxoma virus (MYXV) causes localized cutaneous fibromas in its natural hosts, tapeti and brush rabbits; however, in the European rabbit, MYXV causes the lethal disease myxomatosis. Currently, the molecular mechanisms underlying this increased virulence after cross-species transmission are poorly understood. In this study, we investigated the interaction between MYXV M156 and the host protein kinase R (PKR) to determine their crosstalk with the proinflammatory nuclear factor kappa B (NF-κB) pathway. Our results demonstrated that MYXV M156 inhibits brush rabbit PKR (bPKR) more strongly than European rabbit PKR (ePKR). This moderate ePKR inhibition could be improved by hyperactive M156 mutants. We hypothesized that the moderate inhibition of ePKR by M156 might incompletely suppress the signal transduction pathways modulated by PKR, such as the NF-κB pathway. Therefore, we analyzed NF-κB pathway activation with a luciferase-based promoter assay. The moderate inhibition of ePKR resulted in significantly higher NF-κB–dependent reporter activity than complete inhibition of bPKR. We also found a stronger induction of the NF-κB target genes TNFα and IL-6 in ePKR-expressing cells than in bPKR-expressing cells in response to M156 in both transfection and infections assays. Furthermore, a hyperactive M156 mutant did not cause ePKR-dependent NF-κB activation. These observations indicate that M156 is maladapted for ePKR inhibition, only incompletely blocking translation in these hosts, resulting in preferential depletion of short–half-life proteins, such as the NF-κB inhibitor IκBα. We speculate that this functional activation of NF-κB induced by the intermediate inhibition of ePKR by M156 may contribute to the increased virulence of MYXV in European rabbits.

Rivers are well known as one of the most threatened aquatic environments, whose structure and water quality can be deeply impacted by intensive anthropogenic activities. Despite the fact that anthropogenic influences on river ecosystems could indeed be deduced from the composition and chemistry of fluvial dissolved organic matter (DOM), sources of anthropogenic loading to DOM are still poorly explored. Here, by uniting fluorescence excitation-emission matrices (EEM) and principal component absolute coefficient, four sources of DOM from seventeen rivers in major drainage basins of China could be identified, i.e., originating from municipal sewage, domestic wastewater, livestock wastewater, and natural origins, and thus being defined as MS-DOM, DW-DOM, LW-DOM, NO-DOM, respectively. Based on the random forest model, special nodes in EEM could be traced from four sources, respectively. According to parallel factor analysis, DOM mainly contained protein-like, microbial humic-like, and fulvic-like fluorescence substances, among which protein-like was dominant in MS-DOM and DW-DOM, microbial humic-like in LW-DOM, and fulvic-like in NO-DOM. Based on key peaks and essential nodes in EEM, the identifying source indices were first proposed, which could be introduced to simply distinguish the different anthropogenic-derived sources of fluvial DOM. It was associated with intensity ratios of the key peaks and the essential nodes of EEM spectra from four sources, i.e., municipal sewage (MS-SI: Ex/Em = 280/(335, 410) nm), domestic wastewater (DW-SI: Ex/Em = 280/(340, 410) nm), livestock wastewater (LW-SI: Ex/Em = 235/(345, 380) nm), and natural origins (NO-SI: Ex/Em = 260/(380, 430) nm). By statistical analysis, the high identifying source indices of municipal sewage (>0.5) and natural origins (>0.4) values could be related to MS-DOM and NO-DOM, respectively. The identifying source indices of domestic wastewater with 0.1–0.3 might be linked to DW-DOM and the identifying source indices of livestock wastewater with 0.3–0.4 to LW-DOM. Compared with conventional optical indices, the novel identifying source indices showed remarkable discrimination for the sources of fluvial DOM with different forms of anthropogenic disturbances. Hence the innovative approach could be relatively convenient and accurate to evaluate water quality or pollution risk in river ecosystems. [ABSTRACT FROM AUTHOR]

Prolonged and excessive accumulation of β2-microglobulin (β2m) in the blood can lead to various kidney-related and other diseases. Currently, the most effective method of removing β2m from the blood is hemoperfusion. Although some traditional hemoperfusion adsorbents such as cellulose and polystyrene microspheres have been used for the removal of β2m, their selectivity still needs improvement. Immunosorbents have been developed to address this issue, but high cost and limited application are concerns. TiO2 nanotube arrays (TNTAs) have shown great potential in adsorption-related biomedical applications. In this study, we designed and developed a novel TNTA-based hemoperfusion adsorbent for the removal of β2m, which has demonstrated good biocompatibility, selectivity, and reusability. We investigated the β2m adsorption capacities of TNTAs with different pore sizes. The results indicate that TNTAs with a pore size matching the size of β2m exhibit higher adsorption capacity while also having lower adsorption capacity for albumin, showing the importance of pore size on the selectivity of adsorbents. Additionally, green regeneration of TNTAs is achieved via the photocatalytic activity originating from TiO2. Even after five cycles, the adsorption capacity of TNTAs remained above 70%. Our work demonstrates that inorganic materials with ordered pores are capable to be candidates for hemoperfusion, possessing advantages over traditional organic materials such as high stability, security, and low cost. [ABSTRACT FROM AUTHOR]

To identify the influences of anthropogenic activities on the composition, spatial distribution, sources, and transformation mechanism of sedimentary fulvic acid (FA) fractions from different reaches of an urban river were tracked via excitation-emission matrix (EEM) fluorescence spectroscopy with parallel factor (PARAFAC) analysis and two-dimensional correlation spectroscopy (2D-COS). Sediment samples were collected from Baitapu River (BR) along gradients with human activities (e.g., rural, town, and urban sections) in Shenyang, northeast China, from which FA fractions were extracted and then determined via EEM fluorescence spectroscopy. According to optical indices, the autochthonous sources of sedimentary FA fractions in BR were more significant than the terrestrial sources. Among the sections, the contribution from autochthonous sources decreased in the following order: Rural > Urban > Town. Six components of sedimentary FA fractions were identified via EEM–PARAFAC: C1 comprised tryptophan-like (TRL) compounds; C2 was associated with microbial humic-like (MHL) compounds; C3, C4, and C5 were associated with FA-like (FAL) compounds; and C6 comprised humic acid-like (HAL) compounds. The proportion of sedimentary FA fractions decreased in the following order: MHL + FAL + HAL (humus, 77.37–88.90%) > TRL (protein, 11.10–22.63%) for the three sections, showing that humus dominated. The town section exhibited the highest sedimentary FA fractions (5328.87 ± 1315.82 Raman unit [R.U.]), followed by the urban (4146.49 ± 535.75 R.U.) and rural (2510.56 ± 611.00 R.U.) sections. Three pollution sources were determined via principal component analysis (i.e., the dominant industrial source, domestic wastewater, and agricultural effluent). Additionally, the results from 2D-COS revealed that sedimentary FA fractions tended to stabilize as the protein-like component was transformed into the HAL component. Furthermore, we used the structural equation model to validate the critical environmental variables affecting the FA fraction transformation. The results can elucidate the influences of human activities on the dynamics of sedimentary FA fractions in urban rivers. [ABSTRACT FROM AUTHOR]

Fluorescence tracing, known for its precision, rapid application, and cost-effectiveness, faces challenges due to the microbial degradation of dissolved organic matter (DOM) in aquatic environments, altering its original spectral fingerprint. This study conducted a 15-day microcosm experiment to examine the effects of biodegradation on the spectral properties of DOM from various sources: livestock excrement (EXC), urban sewage (URB), industrial wastewater (IND), and riparian topsoil (tDOM). Our findings show that while the spectral structures of DOM from different sources change during 15 days of microbial degradation, these changes do not overlap or interfere with each other. However, distinguishing between tDOM and URB in the presence of both IND and EXC is only possible at high resolution. Spectral index calculations revealed significant fluctuations and interference in FI and BIX indices among samples from different sources due to microbial degradation. In contrast, the HIX index exhibited independent fluctuations and remained a reliable spectral index for tracing. LEfSe (Linear discriminant analysis Effect Size) identified characteristic bio-indicators (CBI) for each DOM source. The CBI for tDOM and URB differed significantly; tDOM showed a marked CBI only within the first four days of microbial degradation, with a sharp decline in abundance thereafter, while URB's CBI remained abundant for 12 days. Similarly, IND's CBI maintained high relative abundance for the first 12 days. EXC's CBI was unique, showing a distinct and stable community only after six days of degradation, likely due to its high bioavailability and initial rapid microbial utilization. This study addresses the temporal variability in spectral tracing techniques caused by pollutant biodegradation. We developed a combined spectral-biological tracing technique using the "three-dimensional to two-dimensional" method along with bio-indicators, enhancing the accuracy and timeliness of spectral tracing., Competing Interests: Declaration of Competing Interest ☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. ☐ The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:, (Copyright © 2024. Published by Elsevier Inc.)

Prolonged and excessive accumulation of β 2 -microglobulin (β 2 m) in the blood can lead to various kidney-related and other diseases. Currently, the most effective method of removing β 2 m from the blood is hemoperfusion. Although some traditional hemoperfusion adsorbents such as cellulose and polystyrene microspheres have been used for the removal of β 2 m, their selectivity still needs improvement. Immunosorbents have been developed to address this issue, but high cost and limited application are concerns. TiO 2 nanotube arrays (TNTAs) have shown great potential in adsorption-related biomedical applications. In this study, we designed and developed a novel TNTA-based hemoperfusion adsorbent for the removal of β 2 m, which has demonstrated good biocompatibility, selectivity, and reusability. We investigated the β 2 m adsorption capacities of TNTAs with different pore sizes. The results indicate that TNTAs with a pore size matching the size of β 2 m exhibit higher adsorption capacity while also having lower adsorption capacity for albumin, showing the importance of pore size on the selectivity of adsorbents. Additionally, green regeneration of TNTAs is achieved via the photocatalytic activity originating from TiO 2 . Even after five cycles, the adsorption capacity of TNTAs remained above 70%. Our work demonstrates that inorganic materials with ordered pores are capable to be candidates for hemoperfusion, possessing advantages over traditional organic materials such as high stability, security, and low cost.