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1.
Angew Chem Int Ed Engl ; 63(20): e202403083, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38502273

RESUMO

Dopant-free hole transport materials (HTMs) are ideal materials for highly efficient and stable n-i-p perovskite solar cells (PSCs), but most current design strategies for tailoring the molecular structures of HTMs are limited to single strategy. Herein, four HTMs based on dithienothiophenepyrrole (DTTP) core are devised through dual-strategy methods combining conjugate engineering and side chain engineering. DTTP-ThSO with ester alkyl chain that can form six-membered ring by the S⋅⋅⋅O noncovalent conformation lock with thiophene in the backbone shows good planarity, high-quality film, matching energy level and high hole mobility, as well as strong defect passivation ability. Consequently, a remarkable power conversion efficiency (PCE) of 23.3 % with a nice long-term stability is achieved by dopant-free DTTP-ThSO-based PSCs, representing one of the highest values for un-doped organic HTMs based PSCs. Especially, the fill factor (FF) of 82.3 % is the highest value for dopant-free small molecular HTMs-based n-i-p PSCs to date. Moreover, DTTP-ThSO-based devices have achieved an excellent PCE of 20.9 % in large-area (1.01 cm2) devices. This work clearly elucidates the structure-performance relationships of HTMs and offers a practical dual-strategy approach to designing dopant-free HTMs for high-performance PSCs.

2.
Environ Sci Technol ; 57(28): 10319-10330, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37369363

RESUMO

Liquid crystal display (LCD) screens can release many organic pollutants into the indoor environment, including liquid crystal monomers (LCMs), which have been proposed as a novel class of emerging pollutants. Knowing the release pathways and mechanisms of LCMs from various components of LCD screens is important to accurately assess the LCM release and reveal their environmental transport behavior and fate in the ambient environment. A total of 47, 43, and 33 out of 64 target LCMs were detected in three disassembled parts of waste smartphone screens, including the LCM layer (LL), light guide plate (LGP), and screen protector (SP), respectively. Correlation analysis confirmed LL was the source of LCMs detected in LGP and SP. The emission factors of LCMs from waste screen, SP, and LGP parts were estimated as 2.38 × 10-3, 1.36 × 10-3, and 1.02 × 10-3, respectively. A mechanism model was developed to describe the release behaviors of LCMs from waste screens, where three characteristics parameters of released LCMs, including average mass proportion (AP), predicted subcooled vapor pressures (PL), and octanol-air partitioning coefficients (Koa), involving coexistence of absorption and adsorption mechanisms, could control the diffusion-partitioning. The released LCMs in LGP could reach diffusion-partition equilibrium more quickly than those in SP, indicating that LCM release could be mainly governed through SP diffusions.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Cristais Líquidos , Poluentes Atmosféricos/análise , Smartphone , Monitoramento Ambiental
3.
Bioorg Chem ; 140: 106765, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37582330

RESUMO

Janus kinases (JAKs) play a critical role in modulating the function and expression of inflammatory cytokines related to rheumatoid arthritis (RA). Herein, we report the design, synthesis, and structure-activity relationships (SARs) of a series of novel quinazoline derivatives as JAK inhibitors. Among these inhibitors, compound 11n showed high potency against JAKs (JAK1/JAK2/JAK3/TYK2, IC50 = 0.40, 0.83, 2.10, 1.95 nM), desirable metabolic characters, and excellent pharmacokinetic properties. In collagen-induced arthritis (CIA) models, compound 11n exhibited significant reduction in joint swelling with good safety, which could be served as a potential therapeutic candidate for the treatment of inflammatory diseases.


Assuntos
Artrite Reumatoide , Inibidores de Janus Quinases , Humanos , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/uso terapêutico , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Janus Quinases , Relação Estrutura-Atividade , Artrite Reumatoide/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
4.
Altern Ther Health Med ; 29(8): 545-551, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37678852

RESUMO

Context: Clinicians can use stem cells to repair kidney injury. The kidneys' exosome secretions hold the secret to this therapeutic impact. Exosomes from urine-derived stem cells can prevent and treat glomerular damage that diabetes can cause, but the underlying process has remained a mystery. Objective: The study aimed to investigate the protective impact of exosomes from urine-derived stem cells (USCs) against diabetic nephropathy (DN) and to determine the mechanisms involved. Design: The research team performed an animal study. Setting: The study took place at the Affiliated Hospital of Jiujiang University in Jiujiang, Jiangxi, China. Animals: The animals were rats, SD male rats, weighing 200-220g, 40 animals, purchased from Weitong Lihua Experimental Animal Technology Co., Ltd. (certificate number: SCXK (Beijing) 2021-0006). Intervention: Except for a control group, the rats in the groups had induced DN. The five groups, with 10 rats each, were: (1) the negative control group, which received 0.2 ml of PBS solution; (2) the DN group, a second negative control group, which received 0.2 ml of PBS solution, (3) the inhibitor group, an intervention group that received 20 mg/kg of autophagy inhibitor; (4) the exosomes group, an intervention group that received 100 ug/kg of exosomes; and (5) the exosomes + inhibitor group, an intervention group that received 100 ug/kg of exosomes + 20 mg/kg of autophagy inhibitor. From week 8, for four weeks the team injected the inhibitor, exosomes, and exosomes + inhibitor groups with the appropriate treatments using the rats' tail veins. Outcome Measures: The research team: (1) examined the USCs in the exosomes of stem cells; (2) assessed the rats' weights and fasting blood glucose (FBG), using a blood glucose meter; (3) used Coomassie brilliant blue (CBB) staining to determine the amount of protein in the rats' urine and assessed their biochemical indexes; and (4) used Western blot (WB) and a quantitative polymerase chain reaction (Q-PCR) to detect autophagy and the signal transduction pathway. Results: Human exosomes from USCs alleviated injury in the rats that DN caused by reducing urinary-protein levels, serum creatinine (SCR), blood urea nitrogen (BUN), glomerular cell accumulation, and kidney weights. In rats with induced DN, the exosomes + inhibitor significantly reduced the activation of the mTOR signaling pathway, reduced the autophagy of their kidney cells, increased the protein expression of Bcl-2 in the kidney tissues, and lessened the damage to glomerular cells. Conclusions: Human urine-derived stem cell exosomes can significantly reduce the activation of the mTOR signaling pathway, reduce the autophagy of rats' kidney cells, increase the protein expression of LC3B in kidney tissues, and reduce the damage to glomerular cells. By blocking the mTOR signaling pathway, human urogenic exosomes can alleviate the signs and symptoms of DN.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Exossomos , Humanos , Ratos , Masculino , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Glicemia , Exossomos/química , Exossomos/metabolismo , Ratos Sprague-Dawley , Diabetes Mellitus Experimental/induzido quimicamente , Rim , Serina-Treonina Quinases TOR/efeitos adversos , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Células-Tronco/química , Células-Tronco/metabolismo
5.
J Microsc ; 284(3): 244-255, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34494267

RESUMO

The adhesion between asphalt binder and aggregate is very important to the performance and durability of asphalt pavement. In order to explore the characterisation of modified asphalt binder in microstructure during aging and rejuvenation, the virgin asphalt binder and three kinds of modified asphalt binder (styrene-butadiene-styrene block copolymer (SBS), rubber powder and high viscosity and high elasticity [HVHE] modifier) in different aging and rejuvenation condition were prepared. The micromorphology and surface adhesion were measured by atomic force microscopy. The average roughness value was used as the index to evaluate the micromorphology of asphalt binder. The surface adhesion was used as the index to evaluate the adhesion properties of asphalt binder. Results show that the "bee" structure of SBS-modified asphalt binder increased slightly after long-term aging, and the recovery effect of aromatics oil was the closest to that of the unaged one. The rubber powder-modified asphalt binder and HVHE-modified asphalt binder showed the spot structure. And no matter for short-term aging or long-term aging, aromatics oil had the best recovery effect on micro morphology. The adhesion of the three modified asphalts would decrease gradually after aging. The effects of three kinds of rejuvenator on the adhesion of SBS-modified asphalt binder and rubber powder-modified asphalt binder were different. Rejuvenator, aromatic oil and warm mix asphalt mixture (WMA) additive could rejuvenate the loss of adhesion of HVHE-modified asphalt binder to a certain extent.

6.
J Org Chem ; 86(2): 1987-1999, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33378195

RESUMO

We report here an alternatively catalytic aminotrifluoromethylation of alkenes using PhICF3Cl as a bifunctional reagent along with ZnI2 as a dual catalyst. A combined catalytic strategy was established for the intramolecular aminotrifluoromethylation of 4-pentenamines. As a result, a set of 2-trifluoroethyl-pyrrolidines was obtained in a high selectivity. Mechanism studies revealed that the reaction included an iodine anion-catalyzed radical chlorotrifluoromethylation of alkenes and a sequential Lewis acid-promoted aminocyclization of the resulting chlorotrifluoromethylated intermediates.

7.
Water Sci Technol ; 79(11): 2068-2078, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31318344

RESUMO

A simple and efficient route was used to prepare an amphiphilic copolymer (poly(propylene glycol)-co-poly(ethylene glycol)-co-poly(propylene glycol)) (PPG-co-PEG-co-PPG) by one-pot polymerization reaction. This copolymer was used as the hydrophilic additive in preparation of poly(vinylidene fluoride) (PVDF) ultrafiltration membranes via immersion-precipitation process. Surface characteristics of the membranes were confirmed by contact angle measurements, zeta potential, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and atomic force microscopy. During filtration experiments, the modified membranes showed better permeation and antifouling performances compared to PVDF membranes with bovine serum albumin, sodium alginate and yeast. After hydraulic stirring cleaning with deionized water, water flux recovery and rejection ratio of the modified membranes were higher than those of pristine PVDF membrane, and the flux recovery ratio was maximized at 94.29%. It was suggested that PPG-co-PEG-co-PPG copolymer was anchored in the PVDF membrane through the two hydrophobic ends of PPG blocks, while the hydrophilic intermediate of the PEG block segregated onto the membrane or pore surface during the membrane preparation process. The synthesized method of amphiphilic PPG-co-PEG-co-PPG copolymer paved a novel way to solve the problems of less compatibility between the copolymer and membrane matrix and instability with water molecules in the ultrafiltration process.


Assuntos
Membranas Artificiais , Ultrafiltração/métodos , Permeabilidade , Polivinil
8.
Development ; 142(17): 2951-61, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26253401

RESUMO

Vessel formation has been extensively studied at the tissue level, but the difficulty in imaging the endothelium with cellular resolution has hampered study of the morphogenesis and behavior of endothelial cells (ECs) in vivo. We are using endothelial-specific transgenes and high-resolution imaging to examine single ECs in zebrafish. By generating mosaics with transgenes that simultaneously mark endothelial nuclei and membranes we are able to definitively identify and study the morphology and behavior of individual ECs during vessel sprouting and lumen formation. Using these methods, we show that developing trunk vessels are composed of ECs of varying morphology, and that single-cell analysis can be used to quantitate alterations in morphology and dynamics in ECs that are defective in proper guidance and patterning. Finally, we use single-cell analysis of intersegmental vessels undergoing lumen formation to demonstrate the coexistence of seamless transcellular lumens and single or multicellular enclosed lumens with autocellular or intercellular junctions, suggesting that heterogeneous mechanisms contribute to vascular lumen formation in vivo. The tools that we have developed for single EC analysis should facilitate further rigorous qualitative and quantitative analysis of EC morphology and behavior in vivo.


Assuntos
Endotélio/citologia , Endotélio/embriologia , Morfogênese , Análise de Célula Única/métodos , Peixe-Zebra/embriologia , Animais , Polaridade Celular , Embrião não Mamífero/citologia , Células Endoteliais/citologia , Endotélio/irrigação sanguínea , Imageamento Tridimensional , Junções Intercelulares , Espaço Intracelular/metabolismo , Fusão de Membrana , Neovascularização Fisiológica , Reprodutibilidade dos Testes , Tronco/irrigação sanguínea , Tronco/embriologia , Vacúolos/metabolismo
9.
Angew Chem Int Ed Engl ; 57(14): 3701-3705, 2018 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-29430811

RESUMO

Recently, smart surfaces with switchable wettability have aroused much attention. However, only single surface chemistry or the microstructure can be changed on these surfaces, which significantly limits their wetting performances, controllability, and applications. A new surface with both tunable surface microstructure and chemistry was prepared by grafting poly(N-isopropylacrylamide) onto the pillar-structured shape memory polymer on which multiple wetting states from superhydrophilicity to superhydrophobicity can be reversibly and precisely controlled by synergistically regulating the surface microstructure and chemistry. Meanwhile, based on the excellent controllability, we also showed the application of the surface as a rewritable platform, and various gradient wettings can be obtained. This work presents for the first time a surface with controllability in both surface chemistry and microstructure, which starts some new ideas for the design of novel superwetting materials.

10.
Bioorg Med Chem ; 24(18): 4281-4290, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27448775

RESUMO

Aberrant c-Met activation has been implicated in multiple tumor oncogenic processes and drug resistance. In this study, a series of imidazo[4,5-b]pyrazine derivatives was designed and synthesized, and their inhibitory activities were evaluated in vitro. Structure-activity relationship (SAR) was investigated systematically and docking analysis was performed to elucidate the binding mode, leading to the identification of the most promising compound 1D-2 which exhibited significant inhibitory effect on both enzymatic (IC50=1.45nM) and cellular (IC50=24.7nM in H1993 cell line) assays, as well as exquisite selectivity and satisfactory metabolic stability in human and rat liver microsomes.


Assuntos
Imidazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Pirazinas/farmacologia , Animais , Células CACO-2 , Humanos , Imidazóis/síntese química , Imidazóis/química , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirazinas/síntese química , Pirazinas/química , Ratos , Relação Estrutura-Atividade
11.
J Am Soc Nephrol ; 26(4): 864-75, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25214579

RESUMO

The cilium is a signaling platform of the vertebrate cell. It has a critical role in polycystic kidney disease and nephronophthisis. Cilia have been detected on endothelial cells, but the function of these organelles in the vasculature remains incompletely defined. In this study, using genetic and chemical genetic tools in the model organism zebrafish, we reveal an essential role of cilia in developmental vascular integrity. Embryos expressing mutant intraflagellar transport genes, which are essential and specific for cilia biogenesis, displayed increased risk of developmental intracranial hemorrhage, whereas the morphology of the vasculature remained normal. Moreover, cilia were present on endothelial cells in the developing zebrafish vasculature. We further show that the involvement of cilia in vascular integrity is endothelial autonomous, because endothelial-specific re-expression of intraflagellar transport genes in respective mutants rescued the intracranial hemorrhage phenotype. Finally, whereas inhibition of Hedgehog signaling increased the risk of intracranial hemorrhage in ciliary mutants, activation of the pathway rescued this phenotype. In contrast, embryos expressing an inactivating mutation in pkd2, one of two autosomal dominant cystic kidney disease genes, did not show increased risk of developmental intracranial hemorrhage. These results suggest that Hedgehog signaling is a major mechanism for this novel role of endothelial cilia in establishing vascular integrity.


Assuntos
Cílios/fisiologia , Endotélio Vascular/fisiologia , Proteínas Hedgehog/metabolismo , Hemorragias Intracranianas/etiologia , Animais , Células Endoteliais/citologia , Mecanotransdução Celular , Canais de Cátion TRPP/fisiologia , Peixe-Zebra
12.
Emerg Infect Dis ; 21(5): 864-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25897805

RESUMO

During May-August 2013, a malaria outbreak comprising 874 persons in Shanglin County, China, was detected among 4,052 persons returning from overseas. Ghana was the predominant destination country, and 92.3% of malarial infections occurred in gold miners. Preventive measures should be enhanced for persons in high-risk occupations traveling to malaria-endemic countries.


Assuntos
Ouro , Malária/epidemiologia , Malária/transmissão , Mineradores , Viagem , Adolescente , Adulto , Animais , Anopheles/parasitologia , Criança , China/epidemiologia , Surtos de Doenças , Feminino , Geografia , Gana/epidemiologia , Humanos , Malária/diagnóstico , Malária/parasitologia , Masculino , Pessoa de Meia-Idade , Plasmodium malariae , Adulto Jovem
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1735-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26601400

RESUMO

Portable X-ray fluorescence (PXRF) spectrometer as a new type of equipment for quick test has a prominent prospect, but there are also shortcomings of detection range and limition, therefore this paper studied the suitability of PXRF spectrometer in monitoring soil environmental qualities of heavy metals included Cr, Ni, Cu, Zn, Pb, Cd, As and Hg, the aim of this paper is to screen elements which can be detected by this kind of instrument and evaluate the accuracy of test results. The research method is to test heavy metals contaminated soil samples by PXRF spectrometer, evaluate the accuracy of test results of PXRF compared with inductively coupled plasma mass(ICP-MS), then establish linear regression relationship between analysis results of PXRF and ICP-MS method. The results show that, (1) When measuring the soil environmental quality, PXRF spectrometer is appropriate to measure the content of Pb, Zn, Cr and Cu, except Ni, Cd, As and Hg. (2) Compared with the test value of ICP-MS, the test value of Pb and Zn is lower, the test value of Cu is higher, the test value of Cr is too high, all the results of PXRF spectrometer should be linear corrected according to standard analysis method. In conclusion, PXRF spectrometer is suitable for monitoring environmental quality of soil which is polluted by heavy metal such as Pb, Zn, Cr and Cu, it is an analysis means with characteristics of simple and rapid, accurate and reliable. The innovation of this article is that reasonable avoiding the shortcomings of PXRF spectrometer as using the instrument to monitor soil environmental quality, at last improved the application value of test results.

14.
J Diabetes Res ; 2024: 5550812, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774257

RESUMO

Objective: This study is aimed at investigating diagnostic biomarkers associated with lipotoxicity and the molecular mechanisms underlying diabetic nephropathy (DN). Methods: The GSE96804 dataset from the Gene Expression Omnibus (GEO) database was utilized to identify differentially expressed genes (DEGs) in DN patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted using the DEGs. A protein-protein interaction (PPI) network was established to identify key genes linked to lipotoxicity in DN. Immune infiltration analysis was employed to identify immune cells with differential expression in DN and to assess the correlation between these immune cells and lipotoxicity-related hub genes. The findings were validated using the external dataset GSE104954. ROC analysis was performed to assess the diagnostic performance of the hub genes. The Gene set enrichment analysis (GSEA) enrichment method was utilized to analyze the key genes associated with lipotoxicity as mentioned above. Result: In this study, a total of 544 DEGs were identified. Among them, extracellular matrix (ECM), fatty acid metabolism, AGE-RAGE, and PI3K-Akt signaling pathways were significantly enriched. Combining the PPI network and lipotoxicity-related genes (LRGS), LUM and ALB were identified as lipotoxicity-related diagnostic biomarkers for DN. ROC analysis showed that the AUC values for LUM and ALB were 0.882 and 0.885, respectively. The AUC values for LUM and ALB validated in external datasets were 0.98 and 0.82, respectively. Immune infiltration analysis revealed significant changes in various immune cells during disease progression. Macrophages M2, mast cells activated, and neutrophils were significantly associated with all lipotoxicity-related hub genes. These key genes were enriched in fatty acid metabolism and extracellular matrix-related pathways. Conclusion: The identified lipotoxicity-related hub genes provide a deeper understanding of the development mechanisms of DN, potentially offering new theoretical foundations for the development of diagnostic biomarkers and therapeutic targets related to lipotoxicity in DN.


Assuntos
Biomarcadores , Biologia Computacional , Nefropatias Diabéticas , Perfilação da Expressão Gênica , Mapas de Interação de Proteínas , Humanos , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/diagnóstico , Biomarcadores/metabolismo , Lumicana/genética , Lumicana/metabolismo , Ontologia Genética , Redes Reguladoras de Genes , Bases de Dados Genéticas , Transdução de Sinais
15.
Geobiology ; 22(1): e12582, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38385600

RESUMO

We challenge the prevailing view that the end-Permian extinction impeded the Triassic evolution of sponges. Here, we report a deep-water community dominated by abundant keratose sponges in the lowest Triassic strata from Southwest China. The sponge fossils occur as dark elliptical imprints in mudstone with distinct oscula on their tops. The structure of preserved fibers suggests closest affinity with the extant Dictyoceratida, an aspiculate demosponge. The exceptional preservation plays a crucial role in retaining their exquisite structures. Sedimentary, taphonomic, pyrite framboid, and trace elemental analyses indicate that the sponges proliferated in an oxygen-poor habitat, demonstrating the high tolerance of sponges to severe conditions. Sponge proliferation is a signal of environmental upheaval but they also stabilized the ecosystem, driving the first phase of biotic recovery after the end-Permian extinction.


Assuntos
Ceratose , Oligoelementos , Humanos , Ecossistema , Fósseis , China , Biodiversidade
16.
Front Microbiol ; 15: 1290248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873145

RESUMO

Introduction: The impact of nitrogen (N) deposition on the soil N-transforming process in grasslands necessitates further investigation into how N input influences the structural composition and diversity of soil N-cycling microbial communities across different grassland types. Methods: In this study, we selected two types of grassland soils in northwest Liaoning, temperate steppe and warm-temperate shrub, and conducted short-term N addition experiments using organic N, ammonium N, and nitrate N as sources with three concentration gradients to simulate N deposition. Illumina MiSeq sequencing technology was employed to sequence genes associated with N-cycling microbes including N-fixing, ammonia-oxidizing and denitrifying bacteria, and ammonia-oxidizing archaea. Results and discussion: The results revealed significant alterations in the structural composition and diversity of the N-cycling microbial community due to N addition, but the response of soil microorganisms varied inconsistent among different grassland types. Ammonium transformation rates had a greater impact on soils from temperate steppes while nitrification rates were more influential for soils from warm-temperate shrubs. Furthermore, the influence of the type of N source on soil N-cycling microorganisms outweighed that of its quantity applied. The ammonium type of nitrogen source is considered the most influential driving factor affecting changes in the structure of the microbial community involved in nitrogen transformation, while the amount of low nitrogen applied primarily determines the composition of soil bacterial communities engaged in nitrogen fixation and nitrification. Different groups of N-cycling microorganisms exhibited distinct responses to varying levels of nitrogen addition with a positive correlation observed between their composition, diversity, and environmental factors examined. Overall findings suggest that short-term nitrogen deposition may sustain dominant processes such as soil-N fixation within grasslands over an extended period without causing significant negative effects on northwestern Liaoning's grassland ecosystems within the next decade.

17.
ACS Nano ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115190

RESUMO

Organic-inorganic hybrid metal halide perovskite solar cells have been considered as one of the most promising next-generation photovoltaic technologies. Nevertheless, perovskite defects and Li+ ionic migration will seriously affect the power conversion efficiency and stability of the formal device. Herein, we designed two crown ether derivatives (PC12 and PC15) with different cavity diameters, which selectively bind to different metal cations. It is found that PC15 in perovskite precursor solution can actively regulate the nucleation and crystallization processes and passivate the uncoordinated Pb2+ ions, while PC12 at the interface between the perovskite layer and hole-transporting layer can effectively inhibit the migration of Li+ ions and reduce nonradiative recombination losses. Therefore, PC12 and PC15 can act as "lubricant" and defect passivators, as well as inhibitors of ion migration, when they are synergistically applied at the surface and bulk of perovskite layer. Consequently, the optimized device achieved a champion efficiency of 24.8% with significantly improved humidity, thermal, and light stability.

18.
Zhen Ci Yan Jiu ; 49(2): 171-176, 2024 Feb 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38413038

RESUMO

OBJECTIVES: To compare the clinical effect between two acupoint regimens of moxibustion on knee osteoarthritis (KOA), and observe the influences on the serum content of interleukin 1α (IL-1α), interleukin-17A (IL-17A), tumor necrosis factor α (TNF-α), bone gla protein (BGP) and osteoprotegerin (OPG). METHODS: KOA patients were randomly divided into an observation group (40 cases, 2 cases dropped off) and a control group (40 cases, 3 cases dropped off). In the observation group, moxibustion was applied to Xiyan (EX-LE5), Dubi (ST35), Zusanli (ST36), Dazhu (BL11), Xuanzhong (GB39) and Yongquan (KI1) on the affected side. In the control group, EX-LE5, ST35 and ST36 were selected on the affected side. One session of treatment took 30 min in each group, delivered 3 times a week and the duration of treatment was 4 weeks. The scores of Western Ontario and McMaster University (WOMAC) and visual analogue scale (VAS) were observed and the serum content of IL-1α, IL-17A, TNF-α, BGP and OPG of the two groups were measured before and after treatment. RESULTS: Compared with those before treatment, the WOMAC score, VAS score and the serum content of IL-1α, IL-17A and TNF-α were decreased (P<0.05), and the content of BGP and OPG were increased (P<0.05) after treatment. Compared with the control group, the WOMAC score, VAS score and the serum content of IL-1α and TNF-α in the observation group were lower (P<0.05), and the content of BGP and OPG were higher (P<0.05). The total effective rate of the observation group was 89.5% (34/38), and that of the control group was 83.8% (31/37), with no statistically significant difference. CONCLUSIONS: Moxibustion therapy of "nourishing the kidney and benefiting the marrow" can relieve joint pain, improve joint function, reduce the level of inflammatory factors and ameliorate bone metabolic indicators. The effect of the acupoint regimen in this moxibustion therapy is better than that of the local acupoint selection.


Assuntos
Moxibustão , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/terapia , Interleucina-17 , Medula Óssea , Fator de Necrose Tumoral alfa , Resultado do Tratamento , Pontos de Acupuntura , Rim
19.
Mol Pharm ; 10(4): 1360-7, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23391334

RESUMO

Targeting the increased Fe(3+) content in tumors, we propose a novel molecular platform integrated cancer iron chelation therapy for (1)H-magnetic resonance imaging (MRI) detection of ß-galactosidase (ß-gal) activity. Following this idea, we have designed, synthesized, and characterized a series of ß-d-galactosides conjugated with various chelators and demonstrated the feasibility of this concept for assessing ß-gal activity in solution by (1)H-MRI T1 and T2 relaxation mapping.


Assuntos
Terapia por Quelação/métodos , Ferro/farmacologia , Neoplasias/tratamento farmacológico , beta-Galactosidase/metabolismo , Antineoplásicos/farmacologia , Biomarcadores/metabolismo , Quelantes/química , Colorimetria , Humanos , Hidrólise , Ferro/química , Cinética , Óperon Lac , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Modelos Químicos
20.
Front Microbiol ; 14: 1205574, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448571

RESUMO

Introduction: Soil microbial communities are critical in regulating grassland biogeochemical cycles and ecosystem functions, but the mechanisms of how environmental factors affect changes in the structural composition and diversity of soil microbial communities in different grassland soil types is not fully understood in northwest Liaoning, China. Methods: We investigated the characteristics and drivers of bacterial and fungal communities in 4 grassland soil types with 11 sites across this region using high-throughput Illumina sequencing. Results and Discussion: Actinobacteria and Ascomycota were the dominant phyla of bacterial and fungal communities, respectively, but their relative abundances were not significantly different among different grassland soil types. The abundance, number of OTUs, number of species and diversity of both bacterial and fungal communities in warm and temperate ecotone soil were the highest, while the warm-temperate shrub soil had the lowest microbial diversity. Besides, environmental factors were not significantly correlated with soil bacterial Alpha diversity index. However, there was a highly significant negative correlation between soil pH and Shannon index of fungal communities, and a highly significant positive correlation between plant cover and Chao1 index as well as Observed species of fungal communities. Analysis of similarities showed that the structural composition of microbial communities differed significantly among different grassland soil types. Meanwhile, the microbial community structure of temperate steppe-sandy soil was significantly different from that of other grassland soil types. Redundancy analysis revealed that soil total nitrogen content, pH and conductivity were important influencing factors causing changes in soil bacterial communities, while soil organic carbon, total nitrogen content and conductivity mainly drove the differentiation of soil fungal communities. In addition, the degree of connection in the soil bacterial network of grassland was much higher than that in the fungal network and soil bacterial and fungal communities were inconsistently limited by environmental factors. Our results showed that the microbial community structure, composition and diversity of different grassland soil types in northwest Liaoning differed significantly and were significantly influenced by environmental factors. Microbial community structure and the observation of soil total nitrogen and organic carbon content can predict the health changes of grassland ecosystems to a certain extent.

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