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1.
Front Oncol ; 12: 837525, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35530307

RESUMO

Background: Programmed death 1 (PD-1) and the ligand of PD-1 (PD-L1) are central targets for immune-checkpoint therapy (ICT) blocking immune evasion-related pathways elicited by tumor cells. A number of PD-1 inhibitors have been developed, but the efficacy of these inhibitors varies considerably and is typically below 50%. The efficacy of ICT has been shown to be dependent on the gut microbiota, and experiments using mouse models have even demonstrated that modulation of the gut microbiota may improve efficacy of ICT. Methods: We followed a Han Chinese cohort of 85 advanced non-small cell lung cancer (NSCLC) patients, who received anti-PD-1 antibodies. Tumor biopsies were collected before treatment initiation for whole exon sequencing and variant detection. Fecal samples collected biweekly during the period of anti-PD-1 antibody administration were used for metagenomic sequencing. We established gut microbiome abundance profiles for identification of significant associations between specific microbial taxa, potential functionality, and treatment responses. A prediction model based on random forest was trained using selected markers discriminating between the different response groups. Results: NSCLC patients treated with antibiotics exhibited the shortest survival time. Low level of tumor-mutation burden and high expression level of HLA-E significantly reduced progression-free survival. We identified metagenomic species and functional pathways that differed in abundance in relation to responses to ICT. Data on differential enrichment of taxa and predicted microbial functions in NSCLC patients responding or non-responding to ICT allowed the establishment of random forest algorithm-adopted models robustly predicting the probability of whether or not a given patient would benefit from ICT. Conclusions: Overall, our results identified links between gut microbial composition and immunotherapy efficacy in Chinese NSCLC patients indicating the potential for such analyses to predict outcome prior to ICT.

3.
Front Cell Dev Biol ; 10: 836887, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35450295

RESUMO

Mesenchymal stem/stromal cells derived from placenta (PMSCs) are an attractive source for regenerative medicine because of their multidifferentiation potential and immunomodulatory capabilities. However, the cellular and molecular heterogeneity of PMSCs has not been fully characterized. Here, we applied single-cell RNA sequencing (scRNA-seq) and assay for transposase-accessible chromatin sequencing (scATAC-seq) techniques to cultured PMSCs from human full-term placenta. Based on the inferred characteristics of cell clusters, we identify several distinct subsets of PMSCs with specific characteristics, including immunomodulatory-potential and highly proliferative cell states. Furthermore, integrative analysis of gene expression and chromatin accessibility showed a clearer chromatin accessibility signature than those at the transcriptional level on immunomodulatory-related genes. Cell cycle gene-related heterogeneity can be more easily distinguished at the transcriptional than the chromatin accessibility level in PMSCs. We further reveal putative subset-specific cis-regulatory elements regulating the expression of immunomodulatory- and proliferation-related genes in the immunomodulatory-potential and proliferative subpopulations, respectively. Moreover, we infer a novel transcription factor PRDM1, which might play a crucial role in maintaining immunomodulatory capability by activating PRDM1-regulon loop. Collectively, our study first provides a comprehensive and integrative view of the transcriptomic and epigenomic features of PMSCs, which paves the way for a deeper understanding of cellular heterogeneity and offers fundamental biological insight of PMSC subset-based cell therapy.

4.
Carbohydr Polym ; 289: 119419, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35483837

RESUMO

There is a growing interest in the synthesis of electrically conductive cellulose nanocrystal (CNC) for advanced applications, such as supercapacitor, batteries, sensor, and printed electronics. CNC is recognized as an attractive template for the fabrication of functional nanomaterials. Since CNC possesses many attractive properties, it is a sustainable template to prepare conductive nanomaterials, by either coating it with a conductive material or transforming it into carbon nanorods. This review summarizes the utilization of a sustainable and low-cost CNC to produce conductive nanocomposites via an environmentally friendly process. Electroconductive CNCs with enhanced electrical properties, lower electrical percolation threshold, and better mechanical properties can be produced and are attractive systems for many new applications.


Assuntos
Nanocompostos , Nanopartículas , Metabolismo dos Carboidratos , Celulose/química , Condutividade Elétrica , Nanocompostos/química , Nanopartículas/química
5.
Waste Manag ; 144: 313-323, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35427903

RESUMO

The livestock industry has developed rapidly in recent decades, but the improper treatment of livestock manure, especially slurry, causes environmental pollution. Treatment technologies are considered to be effective in alleviating nitrogen (N) and phosphorus (P) losses from livestock slurry. Here, we used published research data to conduct a meta-analysis of the recovery efficiencies of N and P of five mainstream treatment technologies, including ammonia stripping, air scrubbing, membrane filtration, microalgae cultivation and struvite crystallization. Additionally, the agronomic effects of the recovered products of these treatment technologies were evaluated. The results showed that all technologies exhibited clear recovery effects on N and P. The N recovery efficiencies ranged from 57% to 86%, and those of P ranged from 64% to 87%. Struvite crystallization was the most efficient treatment technology for both N and P recovery; moreover, the ammonia stripping and microalgae cultivation technologies were less efficient. The pH levels and temperatures are the main factors that influence ammonia stripping, struvite crystallization and microalgae cultivation, while membrane filtration and air scrubbing are mainly affected by the membrane types and properties. When the equal amount of N or P input to fields, the recovered products (ammonium sulfate and struvite crystals) may achieve a similar crop yield, relative to commercial N or P fertilizers. Our findings can provide deep suggestions and parameters for designing proper treatment technologies to reduce nutrient discharge from livestock slurry in regions with high livestock density and also for identifying the research gaps that should be paid more attention in the future.


Assuntos
Nitrogênio , Fósforo , Amônia/análise , Animais , Gado , Esterco/análise , Nitrogênio/análise , Fósforo/análise , Estruvita/química , Tecnologia
6.
Biochem Biophys Res Commun ; 608: 14-22, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35381424

RESUMO

The characteristics of neonatal immune cells display intrinsic differences compared with adult immune cells. Therefore, a comprehensive analysis of key gene expression regulation is required to understand the response of the human fetal immune system to infections. Here, we applied single-cell RNA sequencing (scRNA-seq) and single-cell sequencing assay for transposase-accessible chromatin (scATAC-seq) to systematically profile umbilical cord blood (UCB) nucleated cells and peripheral blood mononuclear cells (PBMCs) to identify their composition and differentially expressed genes. The immune cells in neonatal UCB demonstrated the expression of key genes, such as HBG2, NFKBIA, JUN, FOS, and TNFAIP3. In contrast, natural killer and T cells, which are constituents of adult PBMCs, exhibited high cytotoxic gene expression. Furthermore, we obtained similar results from the data of scATAC-seq by identifying the status of chromatin accessibility of key genes. Therefore, scRNA-seq and scATAC-seq of neonatal UCB nucleated cells and adult PBMCs could serve as an invaluable resource for elucidating the regulatory mechanisms of responses of distinct immune cell types and further identifying the differences between neonatal and adult immune responses to predict the potential underlying mechanism for neonatal immune tolerance.


Assuntos
Sangue Fetal , Análise de Célula Única , Adulto , Cromatina/metabolismo , Humanos , Tolerância Imunológica/genética , Recém-Nascido , Leucócitos Mononucleares/metabolismo , Análise de Célula Única/métodos , Transposases/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-35388301

RESUMO

Background: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) has poor prognosis and high mortality rate. Curcumae Rhizoma, a classic Chinese medicinal herb, is often used to treat tumors. Methods: Active ingredients of Curcumae Rhizoma were extracted from the Traditional Chinese Medicine Database and Analysis Platform (TCMSP) database, and potential targets were predicted by the TCMSP database and Swiss Target Prediction database. The key drug targets were filtered by intersecting predicted targets, DEGs, and genes in important modules from WGCNA. Besides, the key drug targets were used to construct a network of "herb-active ingredient-target-disease" interactions and subjected to enrichment analysis and protein-protein interaction (PPI) analysis. The hub targets based on PPI analysis was evaluated by the KMplotter database. Results: Three active ingredients of Curcumae Rhizoma were collected with OB ≥ 30% and DL ≥ 0.18, including hederagenin, wenjine, and bisdemethoxycurcumin. The key drug targets were mainly enriched in cell cycle checkpoint, DNA integrity checkpoint, and peptidyl-serine modification. Besides, Curcumae Rhizoma treatment of HBV-related HCC mainly involved the p53 signaling pathway and arachidonic acid metabolism. Finally, ESR1 and PTGS2 were identified as hub targets from PPI analysis. ESR1 was found to be correlated with survival in liver cancer patients with hepatitis. Conclusion: Based on WGCNA and network pharmacological analysis, our results illustrated that Curcumae Rhizoma might work through regulating multitargets and multipathways in HBV-related HCC.

8.
Adv Sci (Weinh) ; : e2200910, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35404518

RESUMO

The ability to quantitatively monitor various cellular activities is critical for understanding their biological functions and the therapeutic response of cells to drugs. Unfortunately, existing approaches such as fluorescent staining and impedance-based methods are often hindered by their multiple time-consuming preparation steps, sophisticated labeling procedures, and complicated apparatus. The cost-effective, monolithic gallium nitride (GaN) photonic chip has been demonstrated as an ultrasensitive and ultracompact optical refractometer in a previous work, but it has never been applied to cell studies. Here, for the first time, the so-called GaN chipscope is proposed to quantitatively monitor the progression of different intracellular processes in a label-free manner. Specifically, the GaN-based monolithic chip enables not only a photoelectric readout of cellular/subcellular refractive index changes but also the direct imaging of cellular/subcellular ultrastructural features using a customized differential interference contrast (DIC) microscope. The miniaturized chipscope adopts an ultracompact design, which can be readily mounted with conventional cell culture dishes and placed inside standard cell incubators for real-time observation of cell activities. As a proof-of-concept demonstration, its applications are explored in 1) cell adhesion dynamics monitoring, 2) drug screening, and 3) cell differentiation studies, highlighting its potential in broad fundamental cell biology studies as well as in clinical applications.

9.
Nanoscale ; 14(13): 5163-5173, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35312742

RESUMO

Bending multi-walled carbon nanotubes (MWCNTs) into rings and structuring them into aerogels is difficult. In this study, cellulose nanofiber (CNF)-MWCNT composite fibers with chain-ring structures were prepared by covalently interconnecting carboxylated CNF and aminated MWCNT by dehydration condensation, solving the problems of the formation of MWCNT aerogels and their phase separation during the compounding process and providing CNF-based aerogels with electrical conductivity. The covalently interconnected aerogels (CAs) had hierarchical porous structures with mechanical resilience and chain-ring fibers, which drove the CNF and MWCNT to form a continuous homogeneous network resulting in a high compression resistance of 269.02 kPa. The CA-based flexible all-solid-state supercapacitor had a quality specific capacitance of 114.8 F g-1, a capacitance retention rate of 94.78% and a Coulomb efficiency of 100%. The CA-based flexible sensor can sense different pressures with a stable response for 1000 cycles. This first study of pulling and bending MWCNT through CNF is expected to inspire more applications of MWCNTs in the fields of flexible supercapacitors and sensors.

10.
Int J Nanomedicine ; 17: 1309-1322, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35345787

RESUMO

Purpose: Osteosarcoma is considered as the most common primary malignant bone tumor in children and adolescents, and the treatments including chemotherapy and surgery were far from satisfactory. Localized tumor treatments by hydrogels incorporating combined chemotherapeutic drugs have recently emerged as superior approaches for enhanced anti-tumor effects and reduced systemic toxicity. Methods: A novel injectable thermosensitive poly (lactide-co- glycolide)-poly (ethylene glycol)-poly(lactide-co-glycolide) triblock copolymer hydrogel containing doxorubicin and cisplatin for the localized chemotherapy of osteosarcoma were synthesized and characterized. The in vitro drug release properties of the drugs-loaded hydrogels were investigated. To study the anti-tumor efficacy of hydrogels depots in vitro, the cytotoxicity and apoptosis rate against Saos-2 and MG-63 cells were evaluated by MTT, Annexin V and PCR methods. The in vivo synergistic anti-tumor efficacy of the multi-drugs co-loaded hydrogels was investigated by human osteosarcoma xenografts. Additionally, the systemic toxic side effects were evaluated by ex vivo histological analysis of the major organs of the mice. Results: The PLGA-PEG-PLGA copolymer solution underwent a sol-gel transition at appropriate temperature and degraded in the PBS, presenting a friendly biocompatibility in vitro. The in vitro cell viability tests demonstrated that DOX and CDDP co-loaded hydrogels exhibited synergistic anti-proliferation effect, due to the sustained release of drugs from the drugs-loaded hydrogel. The treatment with DOX and CDDP co-loaded hydrogel led to the highest efficiency in inhibiting the tumor growth, enhanced tumor necrosis rate and increased regulation of the apoptosis-related gene expressions, indicating a synergistic anti-tumor efficacy in vivo. Additionally, ex vivo histological analysis of the nude mice exhibited low systemic toxicity. Conclusion: The combination treatment of osteosarcoma by localized, sustained co-delivery of DOX and CDDP by PLGA-PEG-PLGA hydrogel may serve as a promising strategy for efficient clinical treatment of osteosarcoma.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Adolescente , Animais , Neoplasias Ósseas/tratamento farmacológico , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Hidrogéis , Camundongos , Camundongos Nus , Osteossarcoma/tratamento farmacológico
11.
ACS Sens ; 7(3): 849-855, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35230822

RESUMO

Salinity is an indispensable parameter for various applications such as biomedical diagnostics, environmental chemical analysis, marine monitoring, etc. Miniaturized salinity sensors have significant potential in portable applications in various scenarios and designs with highly desirable features of convenience, reliability, economy, and high sensitivity and also the capability of real-time measurements. Herein, we demonstrate a highly refractive index-sensitive sensor based on a microscale III-nitride chip that consists of a light emitter and a photodetector. This highly monolithically integrated chip shows an excellent sensitivity of salinity of 2606 nA/(mol/L) (or 446 nA/%) and a response time of 0.243 s. In addition, wireless communication technologies can be easily integrated with the sensing device, which enables automatic remote control for data collection and postprocessing. Remarkably, a polymer-based antifouling coating on the surface of the sensing chip has been established to significantly improve its long-term stability in mimicked marine water. The demonstrated ultrasensitive, ultracompact, cost-effective, fast response, wireless-compatible, and easy-to-use features endow the current device with a huge potential for in situ salinity sensing under varying environmental conditions.


Assuntos
Refratometria , Salinidade , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes , Tecnologia sem Fio
12.
J Agric Food Chem ; 70(12): 3862-3871, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35230117

RESUMO

This study aimed at exploring dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides from silkworm pupae proteins by in silico analysis and in vitro assessments. In silico analysis of 274 silkworm pupae proteomes indicated that DPP-IV inhibitory peptides can be released from silkworm pupae proteins. In vitro assessments revealed that pepsin and bromelain led to better production of DPP-IV inhibitory peptides from silkworm pupae protein. Notably, peptide fractions (<1 kDa) from pepsin- and bromelain-treated hydrolysates exhibited more potent DPP-IV inhibitory activities. Two novel DPP-IV inhibitory peptides (Leu-Pro-Pro-Glu-His-Asp-Trp-Arg and Leu-Pro-Ala-Val-Thr-Ile-Arg) were identified by LC-MS/MS with IC50 values of 261.17 and 192.47 µM, respectively. Enzyme kinetics data demonstrated that these two peptides displayed a mixed-type DPP-IV inhibition mode, which was further validated by molecular docking data. Overall, in silico analysis combined with in vitro assessments can serve as an effective and rapid approach for discovery of DPP-IV peptides from silkworm pupae proteins.


Assuntos
Bombyx , Inibidores da Dipeptidil Peptidase IV , Animais , Bombyx/metabolismo , Cromatografia Líquida , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Simulação de Acoplamento Molecular , Peptídeos/química , Pupa/metabolismo , Espectrometria de Massas em Tandem
13.
ACS Appl Mater Interfaces ; 14(11): 12976-12983, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35282676

RESUMO

Cells live in a highly dynamic environment where their physical connection and communication with the outside are achieved through receptor-ligands binding. Therefore, a precise knowledge of the interaction between receptors and ligands is critical for our understanding of how cells execute different biological duties. Interestingly, recent evidence has shown that the mobility of ligands at the cell-extracellular matrix (ECM) interface significantly affects the adhesion and spreading of cells, while the underlying mechanism remains unclear. Here, we present a modeling investigation to address this critical issue. Specifically, by adopting the Langevin dynamics, the random movement of ligands was captured by assigning a stochastic force along with a viscous drag on them. After that, the evolution of adhesion and subsequent spreading of cells were analyzed by considering the force-regulated binding/breakage of individual molecular bonds connecting polymerizing actin bundles inside the cell to the ECM. Interestingly, a biphasic relationship between adhesion and ligand diffusivity was predicted, resulting in maximized cell spreading at intermediate mobility of ligand molecules. In addition, this peak position was found to be dictated by the aggregation of ligands, effectively reducing their diffusivity, and how fast bond association/dissociation can occur. These predictions are in excellent agreement with our experimental observations where distinct ligand mobility was introduced by tuning the interactions between the self-assembly polymer coating and the surface.


Assuntos
Actinas , Matriz Extracelular , Actinas/metabolismo , Adesão Celular , Movimento Celular , Matriz Extracelular/metabolismo , Ligantes , Polímeros/metabolismo
14.
Angew Chem Int Ed Engl ; 61(21): e202201563, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35178851

RESUMO

Cobalt (CoII ) ions have been an attractive candidate for the biomedical modification of orthopedic implants for decades. However, limited research has been performed into how immobilized CoII ions affect the physical properties of implant devices and how these changes regulate cellular behavior. In this study we modified biocompatible poly(vinyl alcohol) with terpyridine and catechol groups (PVA-TP-CA) to create a stable surface coating in which bioactive metal ions could be anchored, endowing the coating with improved broad-spectrum antibacterial activity against Escherichia coli and Staphylococcus aureus, as well as enhanced surface stiffness and cellular mechanoresponse manipulation. Strengthened by the addition of these metal ions, the coating elicited enhanced mechanosensing from adjacent cells, facilitating cell adhesion, spreading, proliferation, and osteogenic differentiation on the surface coating. This dual-functional PVA-TP-CA/Co surface coating offers a promising approach for improving clinical implantation outcomes.


Assuntos
Polímeros , Álcool de Polivinil , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli , Íons/farmacologia , Osteogênese , Polímeros/farmacologia , Propriedades de Superfície , Titânio/farmacologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-35069764

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effects of a modified Xiaohua Funing decoction (Xfd) on acute liver failure (ALF) and determine whether the protective mechanisms are related to alterations in the gut microbiota. METHODS: An animal model of ALF was induced by intraperitoneal injection of D-galactosamine (D-Gal, 0.5 g/kg) and lipopolysaccharide (LPS, 100 µg/kg). Male BALB/c mice were randomly divided into the following 4 groups: the control group (saline, Con), model group (D-Gal/LPS, Mod), silymarin pretreatment group (200 mg/kg, Sil), and modified Xfd pretreatment group (650 mg/kg, Xfd). The Sil and Xfd groups received the respective intervention orally for 14 days and 2 h before D-Gal/LPS treatment. The liver injury markers included alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and liver histology. 16S rRNA gene sequencing was performed to assess the effects on the caecum content. RESULTS: D-Gal/LPS treatment caused severe ALF, illustrating that the ALF model was successfully established. The administration of Sil and Xfd greatly reduced the serum ALT and AST levels and improved the pathological signs of liver injury. However, no significant difference was found between the two groups. In contrast to the Mod group, the Sil and Xfd groups showed a shift toward the Con group in terms of the gut microbiota structure. The abundances of Firmicutes and Bacteroidetes and the Bacteroidetes/Firmicutes ratio in the Mod group significantly differed from those in the Con group. The Sil and Xfd groups showed restoration of the disordered microbiota. Significantly increased relative abundances of Lachnospiraceae_NK4A136_group and Candidatus_Saccharimonas and a markedly decreased Muribaculaceae abundance were found in the Sil and Xfd mice compared with those in the Mod mice (P < 0.01, P < 0.05). Interestingly, a negative correlation was observed between the abundances of the gut microbiota constituents, specifically Clostridia_UCG-014, and ALT and AST levels. CONCLUSION: In summary, our results indicate that Xfd may protect the liver and modify the gut microbiota in ALF mice.

16.
Nat Genet ; 54(1): 52-61, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980918

RESUMO

The gut microbiome has been implicated in a variety of physiological states, but controversy over causality remains unresolved. Here, we performed bidirectional Mendelian randomization analyses on 3,432 Chinese individuals with whole-genome, whole-metagenome, anthropometric and blood metabolic trait data. We identified 58 causal relationships between the gut microbiome and blood metabolites, and replicated 43 of them. Increased relative abundances of fecal Oscillibacter and Alistipes were causally linked to decreased triglyceride concentration. Conversely, blood metabolites such as glutamic acid appeared to decrease fecal Oxalobacter, and members of Proteobacteria were influenced by metabolites such as 5-methyltetrahydrofolic acid, alanine, glutamate and selenium. Two-sample Mendelian randomization with data from Biobank Japan partly corroborated results with triglyceride and with uric acid, and also provided causal support for published fecal bacterial markers for cancer and cardiovascular diseases. This study illustrates the value of human genetic information to help prioritize gut microbial features for mechanistic and clinical studies.


Assuntos
Sangue/metabolismo , Microbioma Gastrointestinal/genética , Estudos de Coortes , Fezes/microbiologia , Variação Genética , Estudo de Associação Genômica Ampla , Ácido Glutâmico/sangue , Humanos , Análise da Randomização Mendeliana , Metagenoma , Triglicerídeos/sangue
17.
J Nat Prod ; 85(1): 127-135, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35040320

RESUMO

Eight new cadinane sesquiterpenoids (1-8), along with two known compounds (9 and 10), were isolated from infected stems of the semi-mangrove plant, Hibiscus tiliaceus. The structures of compounds 1-8 were elucidated through the analysis of their 1D and 2D NMR and MS data, and their absolute configurations were determined by comparing their experimental and calculated ECD spectra and by single-crystal X-ray diffraction. The two confused known compounds (9 and 10) were resolved using single-crystal X-ray crystallography. Compounds 1-3 have novel norsesquiterpene carbon skeletons arising from a ring contraction rearrangement. All obtained isolates were evaluated against the HepG2 and Huh7 cell lines, and compounds 1b, 2b, 4, 6, and 8 showed cytotoxic activity toward both cell lines, with IC50 values ranging from 3.5 to 6.8 µM.


Assuntos
Hibiscus/química , Caules de Planta/química , Sesquiterpenos Policíclicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/isolamento & purificação , Análise Espectral/métodos
18.
Sci Total Environ ; 816: 151557, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-34762946

RESUMO

Nitrogen (N) management is essential for food security. The North China Plain is an important food producing region, but also a hotspot of N losses to the environment. This results in water, soil, and air pollution. In this study, we aim to quantify the relative contribution of different crops and animals to N losses, by taking the Quzhou county as a typical example in the North China Plain. We developed and applied a new version of the NUtrient flows in Food chains, Environment, and Resource use (NUFER) model. Our model is based on updated information for N losses in Quzhou. Our results show that N losses to the environment from crop and animal production in Quzhou were approximately 9 kton in 2017. These high N losses can be explained by the low N use efficiency in food production because of poor N management. For crop production, wheat, maize, and vegetables contributed 80% to N losses. Ammonia emissions and N leaching have dominant shares in these N losses. Pigs and laying hens were responsible for 74% of N losses from animal production. Ammonia emissions to air and direct discharges of manure to water were the main contributors to these N losses. Effective reduction of N losses requires improving the nutrient management in crop (wheat, maize, vegetables) and animal (pigs, laying hens) production. Our work could support the Agricultural Green Development in the North China Plain.


Assuntos
Fertilizantes , Nitrogênio , Agricultura , Animais , Galinhas , China , Produtos Agrícolas , Fertilizantes/análise , Nitrogênio/análise , Solo , Suínos
19.
J Environ Manage ; 305: 114360, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34954680

RESUMO

The adsorption/desorption behaviors of semi-volatile organic compounds (SVOCs: 1,2,3,4-tetrachlorobenzene (TCB) and phenol) in vapor phase by activated carbon (AC) were investigated by the experiments and density functional theory calculation. Investigations showed that at 100-160 °C, the adsorption capacities of TCB and phenol on AC were in the range of 176.6-342.0 mg/g and 24.0-66.4 mg/g, respectively. Increasing the temperature inhibited the SVOCs adsorption. TCB tended to be adsorbed on AC surface by monolayer, whereas the phenol was multilayer adsorption. The stronger interaction between SVOCs and active sites resulted in a higher desorption temperature (TCB: 255-689 °C; phenol: 200-369 °C). The SVOCs adsorption on AC was fitted well by the pseudo-first-order kinetic model, their lower concentration and larger molecular structure influenced the AC external mass transfer and intraparticle diffusion. TCB and phenol were adsorbed on graphite layer by a parallel manner, their highest adsorption energies were -75.59 kJ/mol and -55.00 kJ/mol, respectively. Oxygen-containing groups altered the charge distribution of the atoms at the edge of the graphite layer, which improved the SVOCs adsorption through enhancement of electrostatic interactions and formation of hydrogen bonds. The carboxyl and lactone groups played a critical role in improving the TCB adsorption capacity, while the carboxyl was important for phenol adsorption.


Assuntos
Carvão Vegetal , Compostos Orgânicos Voláteis , Adsorção , Cinética , Fenol , Fenóis
20.
J Environ Manage ; 302(Pt A): 113960, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34700076

RESUMO

The rapid specialization of livestock production in China has contributed to spatially decoupled crop and livestock production, leading to various environmental pollution issues. Some regional agro-environmental policies have recently promoted the coupling of specialized crop and livestock farms through cooperation. However, the environmental and economic performances of such cooperation remain unclear. This study investigated multiple environmental footprints of two contrasting production systems: cooperative crop-livestock systems (CCLS) and decoupled specialized livestock systems (DSLS), using survey data of 87 ruminant farms in Northwest China. Results show that farms in CCLS had lower net greenhouse gas (GHG) emissions (12-29%), lower reactive nitrogen (Nr) emissions (21-40%), lower phosphorus footprints (PF) (41-54%), and used less cropland (24-31%) per kg animal product, compared to those in DSLS. The large differences in GHG emissions between the two systems were mainly related to enteric fermentation and resource production (used for feed production). The differences in Nr emissions and PF were mainly related to manure management. Net profits per kg animal product were higher in CCLS (13-35%) than in DSLS, and most profits originated from lower purchasing costs of feed and young livestock. Net profits and environmental footprints were negatively correlated, suggesting an environmental and economic win-win situation for CCLS. The possible obstacles to recoupling specialized crop and livestock farms through cooperation have been discussed, including farm size, contract stability, and local policies. Our study provides science-based evidence to support policymakers and specialized farms to close nutrient loops between crop and livestock production sectors through regional cooperation.


Assuntos
Gases de Efeito Estufa , Gado , Animais , Fazendas , Esterco , Nitrogênio
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