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Avian leukosis virus subgroup J (ALV-J), a member of the genus Alpharetrovirus, possesses a small genome and exploits a vast array of host factors during its replication cycle. To identify host factors required for ALV-J replication and potentially guide the development of key therapeutic targets for ALV-J prevention, we employed a chicken genome-wide CRISPR/Cas9 knockout library to screen host factors involved in ALV-J infection within DF-1 cells. This screening revealed 42 host factors critical for ALV-J infection. Subsequent knockout assays showed that the absence of the genes encoding cycle-regulatory proteins, namely, Cables1, CDK1, and DHFR, significantly inhibited ALV-J replication. Notably, Cables1 knockout cell lines displayed the most pronounced inhibitory effect. Conversely, overexpression assays confirmed that Cables1 significantly promotes ALV-J replication. Immunoprecipitation assays further indicated that Cables1 specifically interacts with the viral protein p15 (viral protease) among all ALV-J proteins, enhancing ALV-J p15 polyubiquitination. Additionally, we identified 26 lysine residues of ALV-J p15 as key sites for ubiquitination, and their replacement with arginine attenuated the replication ability of ALV-J in both in vitro and in vivo assays. This study demonstrates that Cables1 is a critical replication-dependent host factor of ALV-J by enhancing p15 ubiquitination and thereby promoting viral replication. Overall, these findings contribute to a deeper understanding of the ALJ-V replication mechanism and offer a potential target for the prevention and control of ALV-J infection.
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Hearing loss is the third leading cause of human disability. Age-related hearing loss, one type of acquired sensorineural hearing loss, is largely responsible for this escalating global health burden. Noise-induced, ototoxic, and idiopathic sudden sensorineural are other less common types of acquired hearing loss. The etiology of these conditions is complex and multi-factorial involving an interplay of genetic and environmental factors. Oxidative stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing loss. Short non-coding RNA sequences known as microRNAs (miRNAs) have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic response. Sensory hair cell death is a central histopathological finding in sensorineural hearing loss. As these cells do not regenerate in humans, it underlies the irreversibility of human age-related hearing loss. Ovid EMBASE, Ovid MEDLINE, Web of Science Core Collection, and ClinicalTrials. gov databases over the period August 1, 2018 to July 31, 2023 were searched with "hearing loss," "hypoxamiRs," "hypoxia," "microRNAs," "ischemia," and "oxidative stress" text words for English language primary study publications or registered clinical trials. Registered clinical trials known to the senior author were also assessed. A total of 222 studies were thus identified. After excluding duplicates, editorials, retractions, secondary research studies, and non-English language articles, 39 primary studies and clinical trials underwent full-text screening. This resulted in 11 animal, in vitro, and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative review. MiRNAs miR-34a and miR-29b levels increase with age in mice. These miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferator-activated receptor gamma coactivator-1-alpha (SIRT1/PGC-1α), SIRT1/p53, and SIRT1/hypoxia-inducible factor 1-alpha signaling pathways resulting in increased apoptosis. Furthermore, hypoxia and oxidative stress had a similar adverse apoptotic effect, which was inhibited by resveratrol and a myocardial inhibitor-associated transcript, a miR-29b competing endogenous mRNA. Gentamicin reduced miR-182-5p levels and increased cochlear oxidative stress and cell death in mice - an effect that was corrected by inner ear stem cell-derived exosomes. There is ongoing work seeking to determine if these findings can be effectively translated to humans.
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BACKGROUND: Postoperative pulmonary complications (PPCs) are common in patients who undergo colorectal surgery. Studies have focused on how to accurately diagnose and reduce the incidence of PPCs. Lung ultrasound has been proven to be useful in preoperative monitoring and postoperative care after cardiopulmonary surgery. However, lung ultrasound has not been studied in abdominal surgeries and has not been used with wearable devices to evaluate the influence of postoperative ambulation on the incidence of PPCs. AIM: To investigate the relationship between lung ultrasound scores, PPCs, and postoperative physical activity levels in patients who underwent colorectal surgery. METHODS: In this prospective observational study conducted from November 1, 2019 to August 1, 2020, patients who underwent colorectal surgery underwent daily bedside ultrasonography from the day before surgery to postoperative day (POD) 5. Lung ultrasound scores and PPCs were recorded and analyzed to investigate their relationship. Pedometer bracelets measured the daily movement distance for 5 days post-surgery, and the correlation between postoperative activity levels and lung ultrasound scores was examined. RESULTS: Thirteen cases of PPCs was observed in the cohort of 101 patients. The mean (standard deviation) peak lung ultrasound score was 5.32 (2.52). Patients with a lung ultrasound score of ≥ 6 constituted the high-risk group. High-risk lung ultrasound scores were associated with an increased incidence of PPCs after colorectal surgery (logistic regression coefficient, 1.715; odds ratio, 5.556). Postoperative movement distance was negatively associated with the lung ultrasound scores [Spearman's rank correlation coefficient (r), -0.356, P < 0.05]. CONCLUSION: Lung ultrasound effectively evaluates pulmonary condition post-colorectal surgery. Early ambulation and respiratory exercises in the initial two PODs will reduce PPCs and optimize postoperative care in patients undergoing colorectal surgery.
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Three new cyclopentanoid monoterpenes, neopiscrocins A-C (1-3), together with 14 known compounds (4-17), were isolated from the roots of Picrorhiza scrophulariiflora. The structres of these compounds were elucidated on the basis of their spectroscopic data. All compounds were evaluated for cytotoxicity against six human tumor cell lines (PC9, PANC1, HCT-116, Hep-G2, BGC-823, and MCF-7), hepatoprotective activity and anti-inflammatory activity.
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The tumor microenvironment (TME) promotes metabolic reprogramming and dysfunction in immune cells. Here, we examined the impact of the TME on phospholipid metabolism in CD8+ T cells. In lung cancer, phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were lower in intratumoral CD8+ T cells than in circulating CD8+ T cells. Intratumoral CD8+ T cells exhibited decreased expression of phospholipid phosphatase 1 (PLPP1), which catalyzes PE and PC synthesis. T cell-specific deletion of Plpp1 impaired antitumor immunity and promoted T cell death by ferroptosis. Unsaturated fatty acids in the TME stimulated ferroptosis of Plpp1-/- CD8+ T cells. Mechanistically, programmed death-1 (PD-1) signaling in CD8+ T cells induced GATA1 binding to the promoter region Plpp1 and thereby suppressed Plpp1 expression. PD-1 blockade increased Plpp1 expression and restored CD8+ T cell antitumor function but did not rescue dysfunction of Plpp1-/- CD8+ T cells. Thus, PD-1 signaling regulates phospholipid metabolism in CD8+ T cells, with therapeutic implications for immunotherapy.
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Linfócitos T CD8-Positivos , Ferroptose , Receptor de Morte Celular Programada 1 , Transdução de Sinais , Microambiente Tumoral , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Animais , Camundongos , Transdução de Sinais/imunologia , Ferroptose/imunologia , Microambiente Tumoral/imunologia , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/genética , Linhagem Celular TumoralRESUMO
BACKGROUND: Lipid droplet (LD)-laden microglia is a key pathological hallmark of multiple sclerosis. The recent discovery of this novel microglial subtype, lipid-droplet-accumulating microglia (LDAM), is notable for increased inflammatory factor secretion and diminished phagocytic capability. Lipophagy, the autophagy-mediated selective degradation of LDs, plays a critical role in this context. This study investigated the involvement of microRNAs (miRNAs) in lipophagy during demyelinating diseases, assessed their capacity to modulate LDAM subtypes, and elucidated the potential underlying mechanisms involved. METHODS: C57BL/6 mice were used for in vivo experiments. Two weeks post demyelination induction at cervical level 4 (C4), histological assessments and confocal imaging were performed to examine LD accumulation in microglia within the lesion site. Autophagic changes were observed using transmission electron microscopy. miRNA and mRNA multi-omics analyses identified differentially expressed miRNAs and mRNAs under demyelinating conditions and the related autophagy target genes. The role of miR-223 in lipophagy under these conditions was specifically explored. In vitro studies, including miR-223 upregulation in BV2 cells via lentiviral infection, validated the bioinformatics findings. Immunofluorescence staining was used to measure LD accumulation, autophagy levels, target gene expression, and inflammatory mediator levels to elucidate the mechanisms of action of miR-223 in LDAM. RESULTS: Oil Red O staining and confocal imaging revealed substantial LD accumulation in the demyelinated spinal cord. Transmission electron microscopy revealed increased numbers of autophagic vacuoles at the injury site. Multi-omics analysis revealed miR-223 as a crucial regulatory gene in lipophagy during demyelination. It was identified that cathepsin B (CTSB) targets miR-223 in autophagy to integrate miRNA, mRNA, and autophagy gene databases. In vitro, miR-223 upregulation suppressed CTSB expression in BV2 cells, augmented autophagy, alleviated LD accumulation, and decreased the expression of the inflammatory mediator IL-1ß. CONCLUSION: These findings indicate that miR-223 plays a pivotal role in lipophagy under demyelinating conditions. By inhibiting CTSB, miR-223 promotes selective LD degradation, thereby reducing the lipid burden and inflammatory phenotype in LDAM. This study broadens the understanding of the molecular mechanisms of lipophagy and proposes lipophagy induction as a potential therapeutic approach to mitigate inflammatory responses in demyelinating diseases.
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Autofagia , Catepsina B , Doenças Desmielinizantes , Gotículas Lipídicas , Lisofosfatidilcolinas , Camundongos Endogâmicos C57BL , MicroRNAs , Microglia , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Microglia/metabolismo , Microglia/patologia , Camundongos , Gotículas Lipídicas/metabolismo , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/patologia , Catepsina B/metabolismo , Catepsina B/genética , Lisofosfatidilcolinas/metabolismo , Modelos Animais de Doenças , Masculino , Regulação da Expressão Gênica , Linhagem CelularRESUMO
AIM: To analyze and compare the differences among ocular biometric parameters in Han and Uyghur populations undergoing cataract surgery. METHODS: In this hospital-based prospective study, 410 patients undergoing cataract surgery (226 Han patients in Tianjin and 184 Uyghur patients in Xinjiang) were enrolled. The differences in axial length (AL), anterior chamber depth (ACD), keratometry [steep K (Ks) and flat K (Kf)], and corneal astigmatism (CA) measured using IOL Master 700 were compared between Han and Uyghur patients. RESULTS: The average age of Han patients was higher than that of Uyghur patients (70.22±8.54 vs 63.04±9.56y, P<0.001). After adjusting for age factors, Han patients had longer AL (23.51±1.05 vs 22.86±0.92 mm, P<0.001), deeper ACD (3.06±0.44 vs 2.97±0.37 mm, P=0.001), greater Kf (43.95±1.40 vs 43.42±1.69 D, P=0.001), steeper Ks (45.00±1.47 vs 44.26±1.71 D, P=0.001), and higher CA (1.04±0.68 vs 0.79±0.65, P=0.025) than Uyghur patients. Intra-ethnic male patients had longer AL, deeper ACD, and lower keratometry than female patients; however, CA between the sexes was almost similar. In the correlation analysis, we observed a positive correlation between AL and ACD in patients of both ethnicities (rHan =0.48, rUyghur =0.44, P<0.001), while AL was negatively correlated with Kf (rHan =-0.42, rUyghur =-0.64, P<0.001) and Ks (rHan =-0.38, rUyghur =-0.66, P<0.001). Additionally, Kf was positively correlated with Ks (rHan =0.89, rUyghur =0.93, P<0.001). CONCLUSION: There are differences in ocular biometric parameters between individuals of Han ethnicity in Tianjin and those of Uyghur ethnicity in Xinjiang undergoing cataract surgery. These ethnic variances can enhance our understanding of ocular diseases related to these parameters and provide guidance for surgical procedures.
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Diabetic foot ulcers often become infected, leading to treatment complications and increased risk of loss of limb. Therapeutics to manage infection and simultaneously promote healing are needed. Here we report on the development of a Janus liposozyme that treats infections and promotes wound closure and re-epithelialization. The Janus liposozyme consists of liposome-like selenoenzymes for reactive oxygen species (ROS) scavenging to restore tissue redox and immune homeostasis. The liposozymes are used to encapsulate photosensitizers for photodynamic therapy of infections. We demonstrate application in methicillin-resistant Staphylococcus aureus-infected diabetic wounds showing high ROS levels for antibacterial function from the photosensitizer and nanozyme ROS scavenging from the liposozyme to restore redox and immune homeostasis. We demonstrate that the liposozyme can directly regulate macrophage polarization and induce a pro-regenerative response. By employing single-cell RNA sequencing, T cell-deficient Rag1-/- mice and skin-infiltrated immune cell analysis, we further reveal that IL-17-producing γδ T cells are critical for mediating M1/M2 macrophage transition. Manipulating the local immune homeostasis using the liposozyme is shown to be effective for skin wound repair and tissue regeneration in mice and mini pigs.
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Homeostase , Oxirredução , Espécies Reativas de Oxigênio , Cicatrização , Animais , Camundongos , Homeostase/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pé Diabético/tratamento farmacológico , Pé Diabético/metabolismo , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/imunologia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/químicaRESUMO
Patchouli oil has exhibited remarkable efficacy in the treatment of colitis. However, its volatility and potential irritancy are often drawbacks when extensively used in clinical applications. Oil gel is a semisolid and thermoreversible system that has received extensive interest for its solubility enhancement, inhibition of bioactive component recrystallization, and the facilitation of controlled bioactive release. Therefore, we present a strategy to develop an oil gel formulation that addresses this multifaceted problem. Notably, a patchouli oil gel formulation was designed to solidify and trap patchouli oil into a spatially stable crystal-particle structure and colonic released delivery, which has an advantage of the stable structure and viscosity. The patchouli oil gel treatment of zebrafish with colitis improved goblet cells and decreased macrophages. Additionally, patchouli oil gel showed superior advantages for restoring the tissue barrier. Furthermore, our investigative efforts unveiled patchouli oil's influence on TRP channels, providing evidence for its potential role in mechanisms of anti-inflammatory action. While the journey continues, these preliminary revelations provide a robust foundation for considering the adoption of patchouli oil gel as a pragmatic intervention for managing colitis.
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Colite , Géis , Peixe-Zebra , Animais , Géis/química , Colite/tratamento farmacológico , Colite/patologia , Colite/induzido quimicamente , Sistemas de Liberação de Medicamentos , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Camundongos , Humanos , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Óleos/químicaRESUMO
Infectious bursal disease (IBD) is an acute and fatal immunosuppressive disease caused by infectious bursal disease virus (IBDV). As an obligate intracellular parasite, IBDV infection is strictly regulated by host factors. Knowledge on the antiviral activity and possible mechanism of host factors might provide the theoretical basis for the prevention and control of IBD. In this study, RNA-sequencing results indicated that many host factors were induced by IBDV infection, among which the expression levels of OASL (2´,5´-oligadenylate synthetase-like protein) was significantly upregulated. OASL overexpression significantly inhibited IBDV replication, whereas OASL knockdown promoted IBDV replication. Interestingly, the antiviral ability of OASL was independent of its canonical enzymatic activity, i.e., OASL targeted viral protein VP2 for degradation, depending on the autophagy receptor p62/SQSTM1 in the autophagy pathway. Additionally, the 316 lysine (K) of VP2 was the key site for autophagy degradation, and its replacement with arginine disrupted VP2 degradation induced by OASL and enhanced IBDV replication. Importantly, our results for the first time indicate a unique and potent defense mechanism of OASL against double-stranded RNA virus by interaction with viral proteins, which leads to their degradation. IMPORTANCE: OASL (2´,5´-oligadenylate synthetase-like protein) exhibits broad-spectrum antiviral effects against single-stranded RNA viruses in mammals, potentially serving as a promising target for novel antiviral strategies. However, its role in inhibiting the replication of double-stranded RNA viruses (dsRNA viruses), such as infectious bursal disease virus (IBDV), in avian species remains unclear. Our findings indicated a unique and potent defense mechanism of OASL against dsRNA viruses. It has been previously shown in mammals that OASL inhibits virus replication through increasing interferon production. The groundbreaking aspect of our study is the finding that OASL has the ability to interact with IBDV viral protein VP2 and target it for degradation and thus exerts its antiviral effect. Our results reveal the interaction between avian natural antiviral immune response and IBDV infection. Our study not only enhances our understanding of bird defenses against viral infections but can also inform strategies for poultry disease management.
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2',5'-Oligoadenilato Sintetase , Autofagia , Infecções por Birnaviridae , Galinhas , Vírus da Doença Infecciosa da Bursa , Proteínas Estruturais Virais , Replicação Viral , Vírus da Doença Infecciosa da Bursa/fisiologia , Animais , Infecções por Birnaviridae/virologia , Infecções por Birnaviridae/metabolismo , Proteínas Estruturais Virais/metabolismo , Proteínas Estruturais Virais/genética , 2',5'-Oligoadenilato Sintetase/metabolismo , 2',5'-Oligoadenilato Sintetase/genética , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/metabolismo , Interações Hospedeiro-Patógeno , Células HEK293 , Humanos , Linhagem CelularRESUMO
Mitigation of nitrous oxide (N2O) emissions in full-scale wastewater treatment plant (WWTP) has become an irreversible trend to adapt the climate change. Monitoring of N2O emissions plays a fundamental role in understanding and mitigating N2O emissions. This paper provides a comprehensive review of direct and indirect N2O monitoring methods. The techniques, strengths, limitations, and applicable scenarios of various methods are discussed. We conclude that the floating chamber technique is suitable for capturing and interpreting the spatiotemporal variability of real-time N2O emissions, due to its long-term in-situ monitoring capability and high data acquisition frequency. The monitoring duration, location, and frequency should be emphasized to guarantee the accuracy and comparability of acquired data. Calculation by default emission factors (EFs) is efficient when there is a need for ambiguous historical N2O emission accounts of national-scale or regional-scale WWTPs. Using process-specific EFs is beneficial in promoting mitigation pathways that are primarily focused on low-emission process upgrades. Machine learning models exhibit exemplary performance in the prediction of N2O emissions. Integrating mechanistic models with machine learning models can improve their explanatory power and sharpen their predictive precision. The implementation of the synergy of nutrient removal and N2O mitigation strategies necessitates the calibration and validation of multi-path mechanistic models, supported by long-term continuous direct monitoring campaigns.
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Monitoramento Ambiental , Óxido Nitroso , Águas Residuárias , Óxido Nitroso/análise , Águas Residuárias/análise , Águas Residuárias/química , Monitoramento Ambiental/métodos , Eliminação de Resíduos Líquidos/métodosRESUMO
Two new iridoid glycosides, piasezkiiosides A (1) and B (2), were isolated from aqueous extract of the whole plant of Rehmannia piasezkii. Their structures were established from the spectroscopic data, chemical transformation, and X-ray diffraction analysis. Compound 1 exhibited weak hepatoprotective activity against APAP-induced HepG2 cell damage.
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Glicosídeos Iridoides , Rehmannia , Glicosídeos Iridoides/farmacologia , Glicosídeos Iridoides/química , Glicosídeos Iridoides/isolamento & purificação , Humanos , Células Hep G2 , Estrutura Molecular , Rehmannia/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificaçãoRESUMO
BACKGROUND: Hypertension is one of the most common chronic diseases with a low control rate globally. The effect of communication skills training contributing to hypertension control remains uncertain. The aim of the present study was to assess the effectiveness of an educational intervention based on the Calgary-Cambridge guide in improving hypertensive management. METHODS: A cluster randomized controlled trial enrolled 27 general practitioners (GPs) and 540 uncontrolled hypertensive patients attending 6 community health centers in Chengdu, China. GPs allocated to the intervention group were trained by an online communication course and two face-to-face workshops based on Calgary-Cambridge guides. The primary outcome was blood pressure (BP) control rates and reductions in systolic and diastolic BP from baseline to 3 months. The secondary outcome was changes in GPs' communication skills after one month, patients' knowledge and satisfaction after 3 months. Bivariate analysis and the regression model assessed whether the health provider training improved outcomes. RESULTS: After the communication training, the BP control rate was significantly higher (57.2% vs. 37.4%, p < 0.001) in the intervention groups. Compared to the control group, there was a significant improvement in GP's communication skills (13.0 vs 17.5, p < 0.001), hypertensive patients' knowledge (18.0 vs 20.0, p < 0.001), and systolic blood pressure (139.1 vs 134.7, p < 0.001) after 3 months of follow-up. Random effects least squares regression models showed significant interactions between the intervention group and time period in the change of GP's communication skills (Parameter Estimated (PE): 0.612, CI:0.310,0.907, p = 0.006), hypertensive patient's knowledge (PE:0.233, CI: 0.098, 0.514, p < 0.001), satisfaction (PE:0.495, CI: 0.116, 0.706, p = 0.004), SBP (PE:-0.803, CI: -1.327, -0.389, p < 0.001) and DBP (PE:-0.918, CI: -1.694, -0.634, p < 0.001), from baseline to follow-up. CONCLUSION: Communication training based on the Calgary-Cambridge guide for GPs has shown to be an efficient way in the short term to improve patient-provider communication skills and hypertension outcomes among patients with uncontrolled BPs. TRIAL REGISTRATION: The trial was registered on Chinese Clinical Trials Registry on 2019-04-03. (ChiCTR1900022278).
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Medicina Geral , Hipertensão , Humanos , Medicina de Família e Comunidade , Pressão Sanguínea , ComunicaçãoRESUMO
In the context of global climate change, sudden rainstorms and typhoons induce fluctuations in hydraulic shocks to wastewater treatment plants (WWTPs) in coastal areas, causing two challenges of stable effluent quality and low-carbon operation. We established a quantitative evaluation method for resistance of wastewater treatment processes to hydraulic shocks based on the water-energy-carbon nexus using operational data from a WWTP in southeast coastal China from July 2018 to December 2022. The effects of hydraulic shocks on the operational stability of the anaerobic-anoxic-oxic-membrane bioreactor (A2/O-MBR) process were analyzed following five steps. The results showed that the gray water footprint (GWF) of the process was 9.3% lower than that of the A2/O process. The energy footprint (ENF) and carbon footprint (CF) were approximately 2.1 times and 1.7 times higher than those of the A2/O process, respectively. The resistance to hydraulic shocks of the A2/O-MBR process is approximately 5.5 times higher than that of the A2/O process. In conclusion, the A2/O-MBR process exhibits higher process operational stability when subjected to hydraulic shocks, which is more conducive to the efficient and stable operation of WWTPs in rainstorm and typhoon-prone areas. The evaluation methodology provides qualitative technical support for selecting upgrading processes for WWTPs in different regions.
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In arid regions, montane lakes are valuable water sources and play important ecological roles. However, recent human-induced inputs of organic pollutants are threatening lake ecology in such regions and becoming a matter of great concern. To investigate pollutant histories and sources, we measured polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in a dated sediment core that spans the last â¼350 years, from montane Lake Issyk-Kul (Kyrgyzstan, Central Asia). Results showed that organic pollutants were delivered to Lake Issyk-Kul in four stages and that their concentrations increased from Stage I (â¼1670-1800 CE) to Stage IV (â¼2000-2010 CE). Furthermore, we tracked the sources of sedimented PAHs using their ratios combined with n-alkanes data. Ratios of PAHs Ant/(Ant + Phe), Flt/(Flt + Pyr) and Bap/BghiP indicated that inputs during Stage II (â¼1800-1970 CE) and Stage III (â¼1970-2000 CE) came mainly from high-temperature combustion of coal and vehicle emissions. PAHs in Stage I and Stage IV, however, were mainly derived from low-temperature combustion and petrogenic sources. Diagnostic PAH ratios, combined with the natural n-alkane ratio (NARï¼0) and unresolved complex mixtures (UCM), showed that the sources of PAHs in Stage I were mainly from erosion of bedrock and partly influenced by forest wildfires, different from the source during Stage IV, which was mainly from refined petroleum caused by accidental spills. Our assessment of the contamination history of the lake indicates that toxicity risk to the waterbody from sediment PAHs is low, but recent discharges arising from traffic deserve attention.
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Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Lagos/química , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Quirguistão , Alcanos/análiseRESUMO
Biomarkers n-alkanes and pertinent indices in lake sediments are frequently used to infer past changes in climate and environmental conditions in and around lakes. Interpretation of n-alkane records can be confounded by a lack of understanding of the multiple factors that control n-alkanes in sediments. Here, we studied n-alkanes in sediment cores from two alpine lakes, Lakes Son-Kul and Issyk-Kul, and from terminal Lake Balkhash, in arid Central Asia to identify natural and human-mediated influences on sediment n-alkane profiles. Altitudinal differences in climate, as well as in lake trophic status, proved to be important drivers of n-alkane compositional differences in the lake sediments. In the alpine lakes, the distribution of n-alkanes was biased toward long-chain components (n-C29, n-C31, and n-C33), and showed higher carbon preference index (CPIH) values, which come from dense terrestrial plant communities, promoted by greater precipitation. In contrast, n-alkanes in the core from the terminal lake displayed higher proportions of short-chain n-alkanes (n-C17, n-C19, and n-C21) because a greater proportion of the organic matter (OM) input to the sediments was derived from algae, a consequence of higher temperatures and trophic status. In recent decades, increasing nutrient inputs from human activities have caused greater accumulation of short-chain n-alkanes in sediments of alpine, oligotrophic Lake Issyk-Kul. In Lake Balkhash, n-C20 and n-C22 alkanes are exceptionally abundant, suggesting large contributions from microbial reworking of terrestrial OM. In all three study lakes, ∑(n-C29-n-C33) was elevated in sediments that correspond to periods of intense agricultural exploitation. Moreover, expansion of agriculture from low to high altitudes resulted in both synchronous and asynchronous peaks in ∑ (n-C29-n-C33) in the studied cores, suggesting the n-alkanes faithfully record the history of agricultural expansion. These findings provide insights into applications of n-alkane proxies and the response of the lake system to climate and anthropogenic impacts.
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The subgroup J avian leukosis virus (ALV-J), a retrovirus, uses its gp85 protein to bind to the receptor, the chicken sodium hydrogen exchanger isoform 1 (chNHE1), facilitating viral invasion. ALV-J is the main epidemic subgroup and shows noteworthy mutations within the receptor-binding domain (RBD) region of gp85, especially in ALV-J layer strains in China. However, the implications of these mutations on viral replication and transmission remain elusive. In this study, the ALV-J layer strain JL08CH3-1 exhibited a more robust replication ability than the prototype strain HPRS103, which is related to variations in the gp85 protein. Notably, the gp85 of JL08CH3-1 demonstrated a heightened binding capacity to chNHE1 compared to HPRS103-gp85 binding. Furthermore, we showed that the specific N123I mutation within gp85 contributed to the enhanced binding capacity of the gp85 protein to chNHE1. Structural analysis indicated that the N123I mutation primarily enhanced the stability of gp85, expanded the interaction interface, and increased the number of hydrogen bonds at the interaction interface to increase the binding capacity between gp85 and chNHE1. We found that the N123I mutation not only improved the viral replication ability of ALV-J but also promoted viral shedding in vivo. These comprehensive data underscore the notion that the N123I mutation increases receptor binding and intensifies viral replication.
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Vírus da Leucose Aviária , Leucose Aviária , Doenças das Aves Domésticas , Animais , Vírus da Leucose Aviária/genética , Vírus da Leucose Aviária/química , Mutação , Galinhas , Isoformas de Proteínas/genética , Proteínas do Envelope Viral/genéticaRESUMO
Monoculture is widely practiced to increase crop productivity, but long-term adaptation has drawbacks as it increases the depletion of soil nutrients and reduces soil quality, especially in dryland areas. Conversion from traditional maize monoculture to intercropping improves sustainable production. However, maize/peanut intercropping, especially rotation of planting strips impacts of maize/peanut intercropping in dryland on carbon (C) budgets and economic benefits remain unclear. In this study, a 5-year field experiment was conducted to evaluate the influence of maize/peanut intercropping with rotation of planting strips on soil health, indirect CO2-eq greenhouse gas emissions, and ecosystem C inputs. Four intercropping treatments viz. maize monoculture, peanut monoculture, maize/peanut intercropping, and maize/peanut rotation-intercropping were tested from 2018 to 2022. Maize/peanut rotation intercropping significantly improved the land equivalent ratio followed by intercropping and monoculture. Rotation-intercropping also improved economic benefits over intercropping and monoculture which were mainly associated with increased peanut yield where the border rows contributed the maximum, followed by the middle rows. Moreover, rotation-intercropping significantly increased the soil organic C and nitrogen (N) content. Rotation-intercropping decreased indirect CO2-eq greenhouse gas emissions and ecosystem C inputs by 3.11% and 18.04%, whereas increased ecosystem C outputs and net ecosystem C budget by 10.38% and 29.14%, respectively, over the average of monoculture. On average for intercropping and monoculture, rotation-intercropping increased ecosystem C emission efficiency for economic benefits by 51.94% and 227.27% in 2021 and 2022, respectively, showing the highest C utilization efficiency than other treatments. In the long run, maize/peanut rotation-intercropping can be practiced in dryland agriculture to achieve sustainable agriculture goals.
Assuntos
Ecossistema , Gases de Efeito Estufa , Arachis , Zea mays , Dióxido de Carbono , Agricultura , Solo , ChinaRESUMO
Thoroughly exploring carbon emissions within Urban Rail Transit (URT) systems is crucial for effectively reducing emissions while satisfying increasing energy demands. This study evaluated the spatiotemporal characteristics of carbon emissions in China's URT sector. Tapio decoupling and the Logarithmic Mean Divisia Index, used to scrutinize decoupling states and identify principal contributing factors, respectively, revealed the following: (1) Total emissions increased by 217 %, with significant spatiotemporal heterogeneity from 2015 to 2022. Type I and Type II cities accounted for >85 % of emissions but exhibited lower carbon intensity. (2) Most URT cities showed expansion-negative decoupling between economic growth and carbon emissions. Developed regions show strong decoupling, and the overall decoupling status improved in 2021-2022. (3) Emissions growth was influenced by energy intensity and economic activity, and transportation intensity was the main inhibitor for Type I cities and a driving force for other cities. Finally, recommendations for carbon emission reduction in the URT industry are proposed.