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BACKGROUND: Macrophage-derived foam cells are a hallmark of atherosclerosis. Scavenger receptors, including lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (OLR-1), are the principal receptors responsible for the uptake and modification of LDL, facilitating macrophage lipid load and the uptake of oxidized LDL by arterial wall cells. Krüppel-like factor 15 (KLF15) is a transcription factor that regulates the expression of genes by binding to the promoter during transcription. Therefore, this study aimed to investigate the precise role of macrophage KLF15 in atherogenesis. METHODS: We used two murine models of atherosclerosis: mice injected with an adeno-associated virus (AAV) encoding the Asp374-to-Tyr mutant version of human PCSK9, followed by 12 weeks on a high-fat diet (HFD), and ApoE-/-- mice on a HFD. We subsequently injected mice with AAV-KLF15 and AAV-LacZ to assess the role of KLF15 in the development of atherosclerosis in vivo. Oil Red O, H&E, and Masson's trichome staining were used to evaluate atherosclerotic lesions. Western blots and RT-qPCR were used to assess protein and mRNA levels, respectively. RESULTS: We determined that KLF15 expression was downregulated during atherosclerosis formation, and KLF15 overexpression prevented atherosclerosis progression. KLF15 expression levels did not affect body weight or serum lipid levels in mice. However, KLF15 overexpression in macrophages prevented foam cell formation by reducing OLR-1-meditated lipid uptake. KLF15 directly targeted and transcriptionally downregulated OLR-1 levels. Restoration of OLR-1 reversed the beneficial effects of KLF15 in atherosclerosis. CONCLUSION: Macrophage KLF15 transcriptionally downregulated OLR-1 expression to reduce lipid uptake, thereby preventing foam cell formation and atherosclerosis. Thus, our results suggest that KLF15 is a potential therapeutic target for atherosclerosis.
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Aterosclerose , Células Espumosas , Humanos , Camundongos , Animais , Células Espumosas/metabolismo , Pró-Proteína Convertase 9/metabolismo , Macrófagos/metabolismo , Aterosclerose/patologia , Lipoproteínas LDL/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismoRESUMO
The available methods of chemical synthesis have arguably contributed to the prevalence of aromatic rings, such as benzene, toluene, xylene, or pyridine, in modern pharmaceuticals. Many such sp2-carbon-rich fragments are now easy to synthesize using high-quality cross-coupling reactions that click together an ever-expanding menu of commercially available building blocks, but the products are flat and lipophilic, decreasing their odds of becoming marketed drugs. Converting flat aromatic molecules into saturated analogues with a higher fraction of sp3 carbons could improve their medicinal properties and facilitate the invention of safe, efficacious, metabolically stable, and soluble medicines. In this study, we show that aromatic and heteroaromatic drugs can be readily saturated under exceptionally mild rhodium-catalyzed hydrogenation, acid-mediated reduction, or photocatalyzed-hydrogenation conditions, converting sp2 carbon atoms into sp3 carbon atoms and leading to saturated molecules with improved medicinal properties. These methods are productive in diverse pockets of chemical space, producing complex saturated pharmaceuticals bearing a variety of functional groups and three-dimensional architectures. The rhodium-catalyzed method tolerates traces of dimethyl sulfoxide (DMSO) or water, meaning that pharmaceutical compound collections, which are typically stored in wet DMSO, can finally be reformatted for use as substrates for chemical synthesis. This latter application is demonstrated through the late-stage saturation (LSS) of 768 complex and densely functionalized small-molecule drugs.
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Ródio , Catálise , Ródio/química , Preparações Farmacêuticas/química , Preparações Farmacêuticas/síntese química , Hidrogenação , Estrutura MolecularRESUMO
CD7-targeted chimeric antigen receptor T-cell (CAR-T) therapy has shown promising initial complete remission (CR) rates in patients with refractory or relapsed (r/r) T-cell acute lymphoblastic leukaemia and lymphoblastic lymphoma (T-ALL/LBL). To enhance the remission duration, consolidation with allogeneic haematopoietic stem cell transplantation (allo-HSCT) is considered. Our study delved into the outcomes of 34 patients with r/r T-ALL/LBL who underwent allo-HSCT after achieving CR with autologous CD7 CAR-T therapy. These were compared with 124 consecutive T-ALL/LBL patients who received allo-HSCT in CR following chemotherapy. The study revealed that both the CAR-T and chemotherapy cohorts exhibited comparable 2-year overall survival (OS) (61.9% [95% CI, 44.1-78.1] vs. 67.6% [95% CI, 57.5-76.9], p = 0.210), leukaemia-free survival (LFS) (62.3% [95% CI, 44.6-78.4] vs. 62.0% [95% CI, 51.8-71.7], p = 0.548), non-relapse mortality (NRM) rates (32.0% [95% CI, 19.0-54.0] vs. 25.3% [95% CI, 17.9-35.8], p = 0.288) and relapse incidence rates (8.8% [95% CI, 3.0-26.0] vs. 15.8% [95% CI, 9.8-25.2], p = 0.557). Patients aged ≤14 in the CD7 CAR-T group achieved high 2-year OS and LFS rates of 87.5%. Our study indicates that CD7 CAR-T therapy followed by allo-HSCT is not only effective and safe for r/r T-ALL/LBL patients but also on par with the outcomes of those achieving CR through chemotherapy, without increasing NRM.
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Antígenos CD7 , Transplante de Células-Tronco Hematopoéticas , Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Indução de Remissão , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Imunoterapia Adotiva/métodos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Receptores de Antígenos Quiméricos/uso terapêutico , Recidiva , Taxa de Sobrevida , Transplante Homólogo , Resultado do TratamentoRESUMO
Patients with acute myocardial infarction complicated with diabetes are more likely to develop myocardial ischemia/reperfusion (I/R) injury (MI/RI) during reperfusion therapy. Both HMGB1 and RAGE play important roles in MI/RI. However, the specific mechanisms of HMGB1 associated with RAGE are not fully clarified in diabetic MI/RI. This study aimed to investigate whether the HMGB1-RAGE axis induces diabetic MI/RI via regulating autophagy and apoptosis. A db/db mouse model of MI/RI was established, where anti-HMGB1 antibody and RAGE inhibitor (FPS-ZM1) were respectively injected after 10â¯min of reperfusion. The results showed that treatment with anti-HMGB1 significantly reduced the infarct size, serum LDH, and CK-MB level. Similar situations also occurred in mice administrated with FPS-ZM1, though the HMGB1 level was unchanged. Then, we found that treatment with anti-HMGB1 or FPS-ZM1 performed the same effects in suppressing the autophagy and apoptosis, as reflected by the results of lower LAMP2 and LC3B levels, increased Bcl-2 level, reduced BAX and caspase-3 levels. Moreover, the Pink1/Parkin levels were also inhibited at the same time. Collectively, this study indicates that the HMGB1-RAGE axis aggravated diabetic MI/RI via apoptosis and Pink1/Parkin mediated autophagy pathways, and inhibition of HMGB1 or RAGE contributes to alleviating those adverse situations.
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Benzamidas , Diabetes Mellitus Experimental , Proteína HMGB1 , Traumatismo por Reperfusão Miocárdica , Animais , Camundongos , Apoptose , Autofagia , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Proteína HMGB1/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Cellular senescence (CS), a state of permanent growth arrest, is intertwined with tumorigenesis. Due to the absence of specific markers, characterizing senescence levels and senescence-related phenotypes across cancer types remain unexplored. Here, we defined computational metrics of senescence levels as CS scores to delineate CS landscape across 33 cancer types and 29 normal tissues and explored CS-associated phenotypes by integrating multiplatform data from ~20 000 patients and ~212 000 single-cell profiles. CS scores showed cancer type-specific associations with genomic and immune characteristics and significantly predicted immunotherapy responses and patient prognosis in multiple cancers. Single-cell CS quantification revealed intra-tumor heterogeneity and activated immune microenvironment in senescent prostate cancer. Using machine learning algorithms, we identified three CS genes as potential prognostic predictors in prostate cancer and verified them by immunohistochemical assays in 72 patients. Our study provides a comprehensive framework for evaluating senescence levels and clinical relevance, gaining insights into CS roles in cancer- and senescence-related biomarker discovery.
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Neoplasias da Próstata , Microambiente Tumoral , Senescência Celular/genética , Genômica , Humanos , Imunoterapia , Masculino , Neoplasias da Próstata/genética , Microambiente Tumoral/genéticaRESUMO
Mycorrhizal associations are key mutualisms that shape the structure of forest communities and multiple ecosystem functions. However, we lack a framework for predicting the varying dominance of distinct mycorrhizal associations in an integrated proxy of multifunctionality across ecosystems. Here, we used the datasets containing diversity of mycorrhizal associations and 18 ecosystem processes related to supporting, provisioning, and regulating services to examine how the dominance of ectomycorrhiza (EcM) associations affects ecosystem multifunctionality in subtropical mountain forests in Southwest China. Meanwhile, we synthesized the prevalence of EcM-dominant effects on ecosystem functioning in forest biomes. Our results demonstrated that elevation significantly modified the distributions of EcM trees and fungal dominance, which in turn influenced multiple functions simultaneously. Multifunctionality increased with increasing proportion of EcM associations, supporting the ectomycorrhizal-dominance hypothesis. Meanwhile, we observed that the impacts of EcM dominance on individual ecosystem functions exhibited different relationships among forest biomes. Our findings highlight the importance of ectomycorrhizal dominance in regulating multifunctionality in subtropical forests. However, this ectomycorrhizal feedback in shaping ecosystem functions cannot necessarily be generalized across forests. Therefore, we argue that the predictions for ecosystem multifunctionality in response to the shifts of mycorrhizal composition could vary across space and time.
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Florestas , Micorrizas , Micorrizas/fisiologia , Clima Tropical , China , Ecossistema , Modelos Biológicos , Árvores/microbiologia , Árvores/fisiologia , Biodiversidade , AltitudeRESUMO
Lidar is an effective remote sensing method to obtain the vertical distribution of aerosols, and how to select the aerosol extinction-backscattering ratio (AE-BR) during the inversion process is a key step to guarantee the accuracy of the lidar inversion of aerosol optical thickness (AOD) and aerosol extinction coefficient profile (AECP). In this paper, an inversion algorithm for AOD and AECP based on a genetic BP (GA-BP) neural network is proposed. Simultaneous measurements are carried out using CE318 sun photometer and lidar, and the mapping relationship between the lidar echo signal and AOD is established based on the genetic BP (GA-BP) neural network method, which achieves the accurate inversion of AOD with an absolute error mean value of 0.0156. Based on the AOD output from the GA-BP neural network, the real-time best AE- BR to improve the inversion accuracy of AECP. Finally, practical tests show that the method achieves accurate inversion of AOD, determines the range of AE-BR from 20-50sr, realizes real-time dynamic correction of AECP, and has strong generalization ability and applicability in practical situations.
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The specific pathophysiological pathways through which diabetes exacerbates myocardial ischemia/reperfusion (I/R) injury remain unclear; however, dysregulation of immune and inflammatory cells, potentially driven by abnormalities in their number and function due to diabetes, may play a significant role. In the present investigation, we simulated myocardial I/R injury by inducing ischemia through ligation of the left anterior descending coronary artery in mice for 40 min, followed by reperfusion for 24 h. Previous studies have indicated that protein kinase Cß (PKCß) is upregulated under hyperglycemic conditions and is implicated in the development of various diabetic complications. The Y4 RNA fragment is identified as the predominant small RNA component present in the extracellular vesicles of cardio sphere-derived cells (CDCs), exhibiting notable anti-inflammatory properties in the contexts of myocardial infarction and cardiac hypertrophy. Our investigation revealed that the administration of Y4 RNA into the ventricular cavity of db/db mice following myocardial I/R injury markedly enhanced cardiac function. Furthermore, Y4 RNA was observed to facilitate M2 macrophage polarization and interleukin-10 secretion through the suppression of PKCß activation. The mechanism by which Y4 RNA affects PKCß by regulating macrophage activation within the inflammatory environment involves the inhibition of ERK1/2 phosphorylation In our study, the role of PKCß in regulating macrophage polarization during myocardial I/R injury was investigated through the use of PKCß knockout mice. Our findings indicate that PKCß plays a crucial role in modulating the inflammatory response associated with macrophage activation in db/db mice experiencing myocardial I/R, with a notable exacerbation of this response observed upon significant upregulation of PKCß expression. In vitro studies further elucidated the protective mechanism by which Y4 RNA modulates the PKCß/ERK1/2 signaling pathway to induce M2 macrophage activation. Overall, our findings suggest that Y4 RNA plays an anti-inflammatory role in diabetic I/R injury, suggesting a novel therapeutic approach for managing myocardial I/R injury in diabetic individuals.
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Modelos Animais de Doenças , Macrófagos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica , Proteína Quinase C beta , Transdução de Sinais , Animais , Proteína Quinase C beta/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/genética , Macrófagos/metabolismo , Macrófagos/enzimologia , Masculino , Interleucina-10/metabolismo , Interleucina-10/genética , Camundongos , Cardiomiopatias Diabéticas/enzimologia , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/fisiopatologia , Células Cultivadas , Fenótipo , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Miócitos Cardíacos/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Ativação de Macrófagos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Função Ventricular Esquerda , FosforilaçãoRESUMO
BACKGROUND: This study investigated the molecular mechanism of long intergenic non-protein coding RNA 1605 (LINC01605) in the process of tumor growth and liver metastasis of pancreatic ductal adenocarcinoma (PDAC). METHODS: LINC01605 was filtered out with specificity through TCGA datasets (related to DFS) and our RNA-sequencing data of PDAC tissue samples from Renji Hospital. The expression level and clinical relevance of LINC01605 were then verified in clinical cohorts and samples by immunohistochemical staining assay and survival analysis. Loss- and gain-of-function experiments were performed to estimate the regulatory effects of LINC01605 in vitro. RNA-seq of LINC01605-knockdown PDAC cells and subsequent inhibitor-based cellular function, western blotting, immunofluorescence and rescue experiments were conducted to explore the mechanisms by which LINC01605 regulates the behaviors of PDAC tumor cells. Subcutaneous xenograft models and intrasplenic liver metastasis models were employed to study its role in PDAC tumor growth and liver metastasis in vivo. RESULTS: LINC01605 expression is upregulated in both PDAC primary tumor and liver metastasis tissues and correlates with poor clinical prognosis. Loss and gain of function experiments in cells demonstrated that LINC01605 promotes the proliferation and migration of PDAC cells in vitro. In subsequent verification experiments, we found that LINC01605 contributes to PDAC progression through cholesterol metabolism regulation in a LIN28B-interacting manner by activating the mTOR signaling pathway. Furthermore, the animal models showed that LINC01605 facilitates the proliferation and metastatic invasion of PDAC cells in vivo. CONCLUSIONS: Our results indicate that the upregulated lncRNA LINC01605 promotes PDAC tumor cell proliferation and migration by regulating cholesterol metabolism via activation of the mTOR signaling pathway in a LIN28B-interacting manner. These findings provide new insight into the role of LINC01605 in PDAC tumor growth and liver metastasis as well as its value for clinical approaches as a metabolic therapeutic target in PDAC.
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BACKGROUND: Timely and complete restoration of blood flow is the most effective intervention for patients with acute myocardial infarction. However, the efficacy is limited by myocardial ischemia-reperfusion (MI/R) injury. PDE4 (phosphodiesterase-4) hydrolyzes intracellular cyclic adenosine monophosphate and it has 4 subtypes A-D. This study aimed to delineate the role of PDE4B (phosphodiesterase-4 subtype B) in MI/R injury. METHODS: Mice were subjected to 30-minute coronary artery ligation, followed by 24-hour reperfusion. Cardiac perfusion was assessed by laser Doppler flow. Vasomotor reactivities were determined in mouse and human coronary (micro-)arteries. RESULTS: Cardiac expression of PDE4B, but not other PDE4 subtypes, was increased in mice following reperfusion. PDE4B was detected primarily in endothelial and myeloid cells of mouse and human hearts. PDE4B deletion strikingly reduced infarct size and improved cardiac function 24-hour or 28-day after MI/R. PDE4B in bone marrow-derived cells promoted MI/R injury and vascular PDE4B further exaggerated this injury. Mechanistically, PDE4B mediated neutrophil-endothelial cell interaction and PKA (protein kinase A)-dependent expression of cell adhesion molecules, neutrophil cardiac infiltration, and release of proinflammatory cytokines. Meanwhile, PDE4B promoted coronary microcirculatory obstruction and vascular permeability in MI/R, without affecting flow restriction-induced thrombosis. PDE4B blockade increased flow-mediated vasodilatation and promoted endothelium-dependent dilatation of coronary arteries in a PKA- and nitric oxide-dependent manner. Furthermore, postischemia administration with piclamilast, a PDE4 pan-inhibitor, improved cardiac microcirculation, suppressed inflammation, and attenuated MI/R injury in mice. Incubation with sera from patients with acute myocardial infarction impaired acetylcholine-induced relaxations in human coronary microarteries, which was abolished by PDE4 inhibition. Similar protection against MI/R-related coronary injury was recapitulated in mice with PDE4B deletion or inhibition, but not with the pure vasodilator, sodium nitroprusside. CONCLUSIONS: PDE4B is critically involved in neutrophil inflammation and microvascular obstruction, leading to MI/R injury. Selective inhibition of PDE4B might protect cardiac function in patients with acute myocardial infarction designated for reperfusion therapy.
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Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Humanos , Inflamação/metabolismo , Microcirculação , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Neutrófilos/metabolismoRESUMO
Assembling a heterostructure is an effective strategy for enhancing the electrocatalytic activity of hybrid materials. Herein, CoFe-layered double hydroxide and Co-metal-organic framework (CoFe-LDH/Co-MOF) hollow heterostructure nanorod arrays are synthesized. First, [Co(DIPL)(H3BTC)(H2O)2]n [named as Co-MOF, DIPL = 2,6-di(pyrid-4-yl)-4-phenylpyridine, H3BTC = 1,3,5-benzenetricarboxylic acid] crystalline materials with a uniform hollow structure were prepared on the nickel foam. The CoFe-LDH/Co-MOF composite perfectly inherits the original hollow nanorod array morphology after the subsequent electrodeposition process. Optimized CoFe-LDH/Co-MOF hollow heterostructure nanorod arrays display excellent performance in oxygen evolution reaction (OER) with ultralow overpotentials of 215 mV to deliver current densities of 10 mA cm-2 and maintain the electrocatalytic activity for a duration as long as 220 h, ranking it one of the non-noble metal-based electrocatalysts for OER. Density functional theory calculations validate the reduction in free energy for the rate-determining step by the synergistic effect of Co-MOF and CoFe-LDH, with the increased charge density and noticeable electron transfer at the Co-O site, which highlights the capability of Co-MOF to finely adjust the electronic structure and facilitate the creation of active sites. This work establishes an experimental and theoretical basis for promoting efficient water splitting through the design of heterostructures in catalysts.
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Birefringent crystals, which can modulate and polarize light, play a vital role in the development of optical sensors and optoelectronic devices. Herein, we synthesized a new birefringent crystal [(C10N2H10)(HI2O6)(HIO3)(IO3)] with large birefringence by integrating the large π-conjugated 4,4'-bipyridine group with two types of iodates anions ([IO3]- and [HI2O6]-) characterized by high polarizability anisotropy and strong stereochemically active lone pairs (SCALP). The crystal exhibits a large measured birefringence of 0.171 at 550 nm, surpassing most organic-inorganic hybrid iodate birefringent materials reported in the literature. Theoretical analyses reveal that the optical properties of the crystal arise primarily from the synergistic interactions between the π-conjugated 4,4'-bipyridine group and I-O groups. This research presents an effective method for the strategic integration of large π-conjugated organic cations into iodates, facilitating the design of novel birefringent materials and encouraging further exploration of superior birefringent substances.
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The pursuit of highly efficient electrocatalysts for the alkaline hydrogen evolution reaction (HER) is of paramount importance for water splitting. However, it is still a formidable task in Mo2C-based materials because of the agglomeration and strong Mo-H binding of Mo2C units. Herein, a novel CeOCl-CeO2/Mo2C heterostructure nesting within a three-dimensional porous nitrogen-doped carbon matrix has been designed and used for catalyzing HER via simultaneous morphology and heterointerface engineering. As expected, the optimal CeOCl-CeO2(0.2)/Mo2C@3DNC exhibits impressive HER activity, with a low overpotential of 156 mV at a current density of 10 mA cm-2 coupled with a slight Tafel slope of 62.20 mV dec-1. Introducing a Ce promoter, that is CeOCl and CeO2, would endow the interface with an internal electric field and electron redistribution between CeOCl-CeO2 and Mo2C induced by the heterogeneous work function difference. Moreover, experimental investigation and density functional calculations confirm that the CeOCl-CeO2/Mo2C heterointerface can downshift the d-band center of the active Mo center, weakening the strength of the Mo-H coupling. This proposed concept, engineering Ce-based promoters into active entities involved in the heterostructure to modulate intermediate adsorption, offers a great opportunity for the design of superior electrocatalysts for energy conversion.
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Rising temperatures can increase the risk of mental disorders. As climate change intensifies, the future disease burden due to mental disorders may be underestimated. Using data on the number of daily emergency department visits for mental disorders at 30 hospitals in Beijing, China during 2016-2018, the relationship between daily mean temperature and such visits was assessed using a quasi-Poisson model integrated with a distributed lag nonlinear model. Emergency department visits for mental disorders attributed to temperature changes were projected using 26 general circulation models under four climate change scenarios. Stratification analyses were then conducted by disease subtype, sex, and age. The results indicate that the temperature-related health burden from mental disorders was projected to increase consistently throughout the 21st century, mainly driven by high temperatures. The future temperature-related health burden was higher for patients with mental disorders due to the use of psychoactive substances and schizophrenia as well as for women and those aged <65 years. These findings enhance our knowledge of how climate change could affect mental well-being and can be used to advance and refine targeted approaches to mitigating and adapting to climate change with a view on addressing mental disorders.
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Mudança Climática , Serviço Hospitalar de Emergência , Transtornos Mentais , Humanos , Transtornos Mentais/epidemiologia , Pequim/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Pessoa de Meia-Idade , Masculino , Adulto , Idoso , Adulto Jovem , Adolescente , Temperatura , China/epidemiologia , Visitas ao Pronto SocorroRESUMO
China is the largest global orchard distribution area, where high fertilization rates, complex terrain, and uncertainties associated with future climate change present challenges in managing non-point source pollution (NPSP) in orchard-dominant growing areas (ODGA). Given the complex processes of climate, hydrology, and soil nutrient loss, this study utilized an enhanced Soil and Water Assessment Tool model (SWAT-CO2) to investigate the impact of future climate on NPSP in ODGA in a coastal basin of North China. Our investigation focused on climate-induced variations in hydrology, nitrogen (N), and phosphorus (P) losses in soil, considering three Coupled Model Intercomparison Project phase 6 (CMIP6) climate scenarios: SSP1-2.6, SSP2-4.5, and SSP5-8.5. Research results indicated that continuous changes in CO2 levels significantly influenced evapotranspiration (ET) and water yield in ODGA. Influenced by sandy soils, nitrate leaching through percolation was the principal pathway for N loss in the ODGA. Surface runoff was identified as the primary pathway for P loss. Compared to the reference period (1971-2000), under three future climate scenarios, the increase in precipitation of ODGA ranged from 15% to 28%, while the growth rates of P loss and surface runoff were the most significant, both exceeding 120%. Orchards in the northwest basin proved susceptible to nitrate leaching, while others were more sensitive to N and P losses via surface runoff. Implementing targeted strategies, such as augmenting organic fertilizer usage and constructing terraced fields, based on ODGA's response characteristics to future climate, could effectively improve the basin's environment.
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Mudança Climática , Poluição Difusa , Fósforo , China , Fósforo/análise , Poluição Difusa/prevenção & controle , Poluição Difusa/análise , Nitrogênio/análise , Solo/química , Agricultura/métodos , Monitoramento Ambiental/métodos , Modelos TeóricosRESUMO
Four new isocoumarin derivatives 12-O-acetyl-isocitreoisocoumarinol (1), (+)-(10R)-O-acetyl-diaportinol (2-a), (-)-(10S)-O-acetyl-diaportinol (2-b), peyroisocoumarin E (3) and new stereoconfigurations of three isocoumarin derivatives desmethyldichlorodiaportinol A (4), threo-monochlorodiaportinol A (5-a), erytheo-monochlorodiaportinol A (5-b), together with nine known ones (6-14), were separated from the rice fermentation of endophytic fungus Diaporthe arengae M2 isolated from Camellia oleifera. The structures of new compounds were determined by extensive spectroscopic analyses including nuclear magnetic resonance (NMR) and high resolution electrospray ionization mass spectroscopy (HR-ESI-MS). Compounds 4, 7, 8, 12, 13 exhibited definite inhibition against five strains of bacteria with the MIC values range from 16 µg/mL to 64 µg/mL.
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Global warming is altering the frequency of extreme rainfall events and introducing uncertainties for non-point source pollution (NPSP). This research centers on orchard-influenced planting areas (OIPA) in the Wulong River Watershed of Shandong Province, China, which are known for their heightened nitrogen (N) and phosphorus (P) pollution. Leveraging meteorological data from both historical (1989-2018) and projected future periods (2041-2100), this research identified five extreme rainfall indices (ERI): R10 (moderate rain), R20 (heavy rain), R50 (rainstorm), R95p (Daily rainfall between the 95th and 99th percentile of the rainfall), and R99p (>99th percentile). Utilizing an advanced watershed hydrological model, SWAT-CO2, this study carried out a comparison between ERI and average conditions and evaluated the effects of ERI on the hydrology and nutrient losses in this coastal watershed. The findings revealed that the growth multiples of precipitation in the OIPA for five ERI varied between 16 and 59 times for the historical period and 14 to 65 times for future climate scenarios compared to the average conditions. The most pronounced increases in surface runoff and total phosphorus (TP) loss were observed with R50, R95p, and R99p, showing growth multiples as high as 352 and 330 times, and total nitrogen (TN) growth multiples varied between 4.6 and 30.3 times. The contribution rates of R50 and R99p for surface runoff and TP loss in the OIPA during all periods exceeded 55%, however, TN exhibited the opposite trend, primarily due to the dominated NO3-N leaching in the sandy soil. This research revealed how the OIPA reacts to different ERI and pinpointed essential elements influencing water and nutrient losses.
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Hidrologia , Nitrogênio , Fósforo , Chuva , Fósforo/análise , Nitrogênio/análise , Nutrientes/análise , China , Rios/química , Monitoramento AmbientalRESUMO
In an era of growing environmental, socioeconomic, and market uncertainties, understanding the adaptive strategies of smallholder farmers is paramount for sustainable agricultural productivity and environmental management efforts. We adopted a mixed-methods approach to investigate the adaptive strategies of smallholders in Northwest Cambodia. Our methodology included downscaled climate projections to project future climate conditions and scenarios, household surveys to collect detailed demographic and socioeconomic data, crop monitoring and record-keeping to gather data on productivity and profitability, and semi-structured interviews to obtain qualitative insights on constraints and adaptation. Our analyses revealed that all smallholders are increasingly vulnerable to climate change which projections reveal will result in more intense and extreme weather events. Specifically, 92% of respondents reported reductions in household income, and 63% indicated the necessity to cut household expenses, which negatively affect agricultural productivity, as evidenced by 33% of respondents reporting declining crop yields and 10% experiencing food shortages. We also uncovered significant differences in farming strategies to mitigate vulnerability among distinct household clusters. Some households prioritise maximising yields through high-expense production strategies, while others focus on optimising inputs to enhance profit-margins, indirectly minimising their environmental impact. These varying strategies have different implications for poverty, food security, and the environment, but were doing very little to mitigate overall vulnerability. To enhance the adaptive capacity of smallholders, policies should target interventions that balance economic growth with environmental sustainability, tailored to the specific needs of different farmer and household types. Promoting the adoption of climate-resilient agricultural practices, investing in water management infrastructure, enhancing access to timely and accurate climate information, and implementing social protection measures are strongly recommended.
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BACKGROUND: Optimizing biochar application is vital for enhancing crop production and ensuring sustainable agricultural production. A 3-year field experiment was established to explore the effects of varying the biochar application rate (BAR) on crop growth, quality, productivity and yields. BAR was set at 0, 10, 50 and 100 t ha-1 in 2018; 0, 10, 25, 50 and 100 t ha-1 in 2019; and 0, 10, 25 and 30 t ha-1 in 2020. Crop quality and growth status and production were evaluated using the dynamic technique for order preference by similarity to ideal solution with the entropy weighted method (DTOPSIS-EW), principal component analysis (PCA), membership function analysis (MFA), gray relation analysis (GRA) and the fuzzy Borda combination evaluation method. RESULTS: Low-dose BAR (≤ 25 t ha-1 for cotton; ≤ 50 t ha-1 for sugar beet) effectively increased biomass, plant height, leaf area index (LAI), water and fertility (N, P and K) productivities, and yield. Biochar application increased the salt absorption and sugar content in sugar beet, with the most notable increases being 116.45% and 20.35%, respectively. Conversely, BAR had no significant effect on cotton fiber quality. The GRA method was the most appropriate for assessing crop growth and quality. The most indicative parameters for reflecting cotton and sugarbeet growth and quality status were biomass and LAI. The 10 t ha-1 BAR consistently produced the highest scores and was the most economically viable option, as evaluated by DTOPSIS-EW. CONCLUSION: The optimal biochar application strategy for improving cotton and sugar beet cultivation in Xinjiang, China, is 10 t ha-1 biochar applied continuously. © 2024 Society of Chemical Industry.
Assuntos
Beta vulgaris , Carvão Vegetal , Produção Agrícola , Fertilizantes , Gossypium , Beta vulgaris/química , Beta vulgaris/crescimento & desenvolvimento , Carvão Vegetal/química , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , China , Produção Agrícola/métodos , Fertilizantes/análise , BiomassaRESUMO
Dearomative partial reduction is an extraordinary approach for transforming benzenoid arenes and has been well-known for many decades, as exemplified by the dehydrogenation of Birch reduction and the hydroarylation of Crich addition. Despite its remarkable importance in synthesis, this field has experienced slow progress over the last half-century. However, a revival has been observed with the recent introduction of electrochemical and photochemical methods. In this Minireview, we summarize the recent advancements in dearomative partial reduction of benzenoid arenes, including dihydrogenation, hydroalkylation, arylation, alkenylation, amination, borylation and others. Further, the intriguing utilization of dearomative partial reduction in the synthesis of natural products is also emphasized. It is anticipated that this Minireview will stimulate further progress in arene dearomative transformations.