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Introduction: A series of significant ecological construction projects in the southern hilly region have brought about substantial changes to the ecological status and comprehensive zoning of the region. Hunan Province, with its strategic significance, was chosen as a representative research subject in the southern hilly region. Methods: We conducted a dynamic evaluation of the ecological status change and comprehensive zoning of Hunan Province from a structure-function perspective by applying the transfer matrix, Theil-Sen, Mann-Kendall, and ecosystem service trade-offs or synergies methods. The research goal was to integrate and harmonize structural complexity and functional diversification, providing valuable insights for optimizing both ecological background and territorial background. Results: The main results are as follows: (1) The structural changes of ecosystems were mainly concentrated in settlement and Cropland ecosystems. While the area of bulti-up ecosystems has increased significantly, from 1.34% in 2000 to 2.72% in 2020. Cropland ecosystems marking a decrease of 1.39%, with a continued conversion of Cropland into construction land ecosystems. (2) Ecosystem function changes have introduced instability. Over time, NPP exhibited an oscillating trend of increase followed by a decrease. Spatially, there was a sharp decline in peripheral building land, and the regions of declining NPP displayed a lateral U-shaped distribution. (3) The overall trend in ecosystem service changes was positive. Quantitatively, GP and CS experienced an ascending-then-decreasing pattern, while HQ showed a weak decline and WY increased annually. At the county scale, there was noticeable spatial heterogeneity. Human socio-economic activities and environmental protection policies exert a significant impact on the ecological conditions within the study area. (4) Regarding the national territory space function partition, urban functional zones have primarily catered to residential functions and were mainly distributed in the Changsha-Zhuzhou-Xiangtan area. Discussion: Ecological functional zones were mainly centered on ecological functions, and most were located in the mountainous areas of western and southern Hunan Province. The agricultural function areas were mainly to serve production functions and were mainly located in the Dongting Lake Plain, the nearshore plain of the mainstream and tributary systems of the rivers of Xiang, Zi, Yuan, and Li. In general, the changes in ecosystem structure and function in the study area reflect changes in ecological conditions. In the future, ecosystem diversity, stability, and sustainability should be improved from an integrated structure-function perspective. [ABSTRACT FROM AUTHOR]

The renin–angiotensin system (RAS) and hypoxia have a complex interaction: RAS is activated under hypoxia and activated RAS aggravates hypoxia in reverse. Renin is an aspartyl protease that catalyzes the first step of RAS and tightly regulates RAS activation. Here, we outline kidney renin expression and release under hypoxia and discuss the putative mechanisms involved. It is important that renin generally increases in response to acute hypoxemic hypoxia and intermittent hypoxemic hypoxia, but not under chronic hypoxemic hypoxia. The increase in renin activity can also be observed in anemic hypoxia and carbon monoxide-induced histotoxic hypoxia. The increased renin is contributed to by juxtaglomerular cells and the recruitment of renin lineage cells. Potential mechanisms regulating hypoxic renin expression involve hypoxia-inducible factor signaling, natriuretic peptides, nitric oxide, and Notch signaling-induced renin transcription. [ABSTRACT FROM AUTHOR]

To evaluate the effect of Nirmatrelvir‐ritonavir therapy and coronavirus disease 2019 (COVID‐19) vaccination on clinical outcomes of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) Omicron infection, we retrospectively analyzed the clinical data of 762 adult patients with confirmed Omicron BA2.2 variant infection, of them 488 patients received standard therapy and 274 patients received Nirmatrelvir‐ritonavir therapy. Subjects were matched by propensity score matching using R language, the baseline factors were balanced by the nearest‐neighbor matching method and were compared, together with the factors including progression to severe/critical disease, viral clearance time, length of hospital stay, and virological rebound of SARS‐CoV‐2 infection. Nirmatrelvir‐ritonavir therapy significantly accelerated viral clearance at Days 14 and 28 during hospitalization, but it had no impact on disease progression, length of hospital stay, or infection rebound. In contrast, COVID‐19 vaccination before admission was positively correlated with the viral clearance rate and negatively correlated with disease progression in a dose‐dependent way. COVID‐19 vaccination reduced the probability of infection rebound. Other factors such as the number of comorbidities, pneumonia on‐admission, and high D2 levels were positively correlated with disease progression. Our study strongly recommended booster COVID‐19 vaccination for the elderly population, particularly patients with comorbidities to prevent critical disease. [ABSTRACT FROM AUTHOR]

Aims: In patients with renal disease, high serum phosphate shows a relationship with cardiovascular risk. We speculate that high phosphate (HP) impairs arterial vasodilation via the endothelium and explore potential underlying mechanisms. Methods: Isolated vessel relaxation, endothelial function, glomerular filtration rate (GFR), oxidative stress status and protein expression were assessed in HP diet mice. Mitochondrial function and protein expression were assessed in HP‐treated human umbilical vein endothelial cells (HUVECs). Results: High phosphate (1.3%) diet for 12 weeks impaired endothelium‐dependent relaxation in mesenteric arteries, kidney interlobar arteries and afferent arterioles; reduced GFR and the blood pressure responses to acute administration of acetylcholine. The PPARα/LKB1/AMPK/eNOS pathway was attenuated in the endothelium of mesenteric arteries from HP diet mice. The observed vasodilatory impairment of mesenteric arteries was ameliorated by PPARα agonist WY‐14643. The phosphate transporter PiT‐1 knockdown prevented HP‐mediated suppression of eNOS activity by impeding phosphorus influx in HUVECs. Endothelium cytoplasmic and mitochondrial reactive oxygen species (ROS) were increased in HP diet mice. Moreover HP decreased the expression of mitochondrial‐related antioxidant genes. Finally, mitochondrial membrane potential and PGC‐1α expression were reduced by HP treatment in HUVECs, which was partly restored by AMPKα agonist. Conclusions: HP impairs endothelial function by reducing NO bioavailability via decreasing eNOS activity and increasing mitochondrial ROS, in which the AMPK‐related signalling pathways may play a key role. [ABSTRACT FROM AUTHOR]

Aims: Reduced A Disintegrin And Metalloproteinase with a ThromboSpondin type 1 motif member 13 (ADAMTS13) levels are observed in kidney disease. We test whether recombinant human ADAMTS13 (rhADAMTS13) mitigates renal injury in chronic kidney disease (CKD) and the potential mechanisms. Methods: CKD was established 3 months after ischaemia/reperfusion (IR). ADAMTS13 and von Willebrand factor (vWF) levels, renal function and morphological changes were analysed. Afferent arteriolar responses to angiotensin II (Ang II) and acetylcholine (ACh) were measured. Oxidative stress‐related molecules were detected. Results: Higher vWF and lower ADAMTS13 levels were observed in CKD mice, which were markedly attenuated by rhADAMTS13. rhADAMTS13 alleviated renal dysfunction, as documented by decreased blood urea nitrogen (BUN), serum creatinine, kidney injury molecule‐1 (KIM‐1) and neutrophil gelatinase‐associated lipocalin (NGAL) levels in CKD mice. Moreover, rhADAMTS13 attenuated transforming growth factor (TGF)‐β1/Smad3 activation. Plasma vWF: ADAMTS13 ratio showed positive correlations with malondialdehyde (MDA), hydrogen peroxide (H2O2) and proteinuria, and correlated inversely with superoxide dismutase (SOD) and catalase (CAT). Finally, rhADAMTS13 inhibited reactive oxygen species (ROS) levels and improved microvascular functional disorders, accompanied by the inhibition of glycogen synthase kinase (GSK) 3β hyperactivity and upregulation of nuclear factor erythroid 2‐related factor 2 (Nrf2) expression. Conclusions: Acute kidney injury (AKI) reduces the expression of ADAMTS13 that contributes to progressive CKD, microvascular dysfunction, oxidative stress, inhibition of Nrf2 activity and renal histopathological damage. All of which can be alleviated by administration of rhADAMTS13. [ABSTRACT FROM AUTHOR]

T cells play a critical role in coronavirus diseases. How they do so in COVID-19 may be revealed by analyzing the epigenetic chromatin accessibility of cis- and trans-regulatory elements and creating transcriptomic immune profiles. We performed single-cell assay for transposase-accessible chromatin (scATAC) and single-cell RNA (scRNA) sequencing (seq) on the peripheral blood mononuclear cells (PBMCs) of severely ill/critical patients (SCPs) infected with COVID-19, moderate patients (MPs), and healthy volunteer controls (HCs). About 76,570 and 107,862 single cells were used, respectively, for analyzing the characteristics of chromatin accessibility and transcriptomic immune profiles by the application of scATAC-seq (nine cases) and scRNA-seq (15 cases). The scATAC-seq detected 28,535 different peaks in the three groups; among these peaks, 41.6 and 10.7% were located in the promoter and enhancer regions, respectively. Compared to HCs, among the peak-located genes in the total T cells and its subsets, CD4+ T and CD8+ T cells, from SCPs and MPs were enriched with inflammatory pathways, such as mitogen-activated protein kinase (MAPK) signaling pathway and tumor necrosis factor (TNF) signaling pathway. The motifs of TBX21 were less accessible in the CD4+ T cells of SCPs compared with those in MPs. Furthermore, the scRNA-seq showed that the proportion of T cells, especially the CD4+ T cells, was decreased in SCPs and MPs compared with those in HCs. Transcriptomic results revealed that histone-related genes, and inflammatory genes, such as NFKBIA, S100A9, and PIK3R1, were highly expressed in the total T cells, CD4+ T and CD8+ T cells, both in the cases of SCPs and MPs. In the CD4+ T cells, decreased T helper-1 (Th1) cells were observed in SCPs and MPs. In the CD8+T cells, activation markers, such as CD69 and HLA class II genes (HLA-DRA, HLA-DRB1, and HLA-DRB5), were significantly upregulated in SCPs. An integrated analysis of the data from scATAC-seq and scRNA-seq showed some consistency between the approaches. Cumulatively, we have generated a landscape of chromatin epigenetic status and transcriptomic immune profiles of T cells in patients with COVID-19. This has provided a deeper dissection of the characteristics of the T cells involved at a higher resolution than from previously obtained data merely by the scRNA-seq analysis. Our data led us to suggest that the T-cell inflammatory states accompanied with defective functions in the CD4+ T cells of SCPs may be the key factors for determining the pathogenesis of and recovery from COVID-19. [ABSTRACT FROM AUTHOR]

To utilize its rich aromatics, lignin, a high-volume waste and environmental hazard, was depolymerized in supercritical ethanol over various zeolites types with different acidity and pore structures. Targeting at high yield/selectivity of aromatics such as phenols, microporous Beta, Y, and ZSM-5 zeolites were first examined in lignin ethanolysis, followed by zeolites with similar micropore size but different acidity. Further comparisons were made between zeolites with fin-like and worm-like mesoporous structures and their microporous counterparts. Despite depolymerization complexity and diversified ethanolysis products, strong acidity was found effective to cleave both C–O–C and C–C linkages of lignin while mild acidity works mainly in ether bond breakdown. However, when diffusion of gigantic molecules is severe, pore size, particularly mesopores, becomes more decisive on phenol selectivity. These findings provide important guidelines on future selection and design of zeolites with appropriate acidity and pore structure to promote lignin ethanolysis or other hydrocarbon cracking processes. [ABSTRACT FROM AUTHOR]

Human endometrium decidualization, which involves endometrial stromal proliferation and differentiation, is a prerequisite for embryo implantation, thus successful pregnancy. The Forkhead Box M1 (FoxM1), previously known as HNF-3, HFH-11, MPP2, Win, and Trident, is a transcriptional factor that plays crucial roles in cell proliferation and cell cycle progression. However, the molecular mechanism of FoxM1 during human endometrial decidualization remains unexplored. In this study, we first found FoxM1 is dynamically expressed in human endometrium during menstrual cycle. Employing a human endometrial stromal cell (HESC) line, we then demonstrated that FoxM1 inhibition downregulates cyclin B1 expression, delaying G2/M phase transition during HESC proliferation. Additionally, loss of FoxM1 expression blocks the differentiation of HESCs in response to estrogen, progesterone, and dbcAMP. Applying chromatin immunoprecipitation (ChIP) technique and luciferase assay, we further approved that FoxM1 can transcriptionally active signal transducer and activator of transcription 3 (STAT3), ensuring normal HESC differentiation. Besides enriching our knowledge on molecular basis underlying stromal decidualization, these findings help to shed light on the potential molecular causes for the endometrial disorders in humans. [ABSTRACT FROM AUTHOR]

Silicon-rich anodes are desired to leverage the energy capacity of lithium-ion batteries (LIBs) towards critical markets. We prepared new silicon-rich composite anodes with a nanofiber-in-microfiber architecture using a co-axial electrospinning setup. A polyvinyl alcohol (PVA) solution that allows high silicon content serves as the central stream, which holds silicon nanoparticles into short, branched composite nanofibers. These nanofibers were wrapped by long, ductile microfibers made of polyacrylonitrile (PAN) that is supplied in the sheath fluid. After carbonization, the received carbon/silicon composites were tested as the anode of LIBs, in which the silicon-rich nanofibers host the majority of lithium ions while their thin carbon skin originated from PVA promotes the conductivity and charge transfer. The outside PAN-derived microfibers provide needed structural support for those encapsulated silicon-rich nanofibers, making the final composites also an integrated, three-dimensional current collector. The nanofibrous morphology and the void space in between help accommodate the notorious volume expansion issues during lithiation/delithiation. The new composites were confirmed on their nanofiber-in-microfiber configuration. With a Si content of 40%, this unique fibrous anode material achieves ∼900 mAh g−1 specific capacity and ∼90% capacity retention from cycle 50 to cycle 250 by effectively balancing some major challenges associated with silicon-rich anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

• Solid crystallization of dry nanogels into mesoporous ZSM-5 at ambient pressure. • Hierarchical pore structure created by jointing nanocrystals into single zeolites. • Low temperature hydrogenation/deoxygenation of Pd/Meso-ZSM-5 catalyst. • Improved conversion and anti-coking performance in guaiacol hydrodeoxygenation. • Saturated/unsaturated product regulated by hydrodeoxygenation temperature. Mesoporous structure is important to promote mass transport and active site utilization of zeolites when used in reactions involving bulky molecules. However, their conventional hydrothermal synthesis is energy and labor intensive, requiring high-pressure operation, and lengthy heating a huge amount of alkaline liquid. We successfully synthesized new mesoporous zeolites, Meso-ZSM-5, via solid-state crystallization of dry aluminosilicate nanogels. Neighbor developing nanocrystals further joint at edges, creating connected, inter-lattice mesoscale pathway in the finished single crystalline zeolites. Palladium was further loaded on these zeolites to form a bi-functional catalyst (Pd/Meso-ZSM-5). When used in the hydrodeoxygenation (HDO) of guaiacol, a major bio-oil compound with disappointing conversion and severe coking issue over many HDO catalysts, Pd/Meso-ZSM-5 exhibits superior guaiacol conversion and product distribution when compared with those supported on conventional microporous ZSM-5 counterparts. This is attributed to the improved diffusion and accessibility of active sites inside Meso-ZSM-5 with its unique hierarchically porous structure. Ring saturated hydrocarbons are largely produced at 200 °C when hydrogenation dominates while alkaylated aromatics become major HDO products as deoxygenation becomes favorable at 250 °C. These encouraging results may ignite the wide use of these mesoporous zeolites in many other reactions in both traditional fossil fuel and emerging renewable energy fields. [ABSTRACT FROM AUTHOR]