RESUMO
This study aimed to prepare effervescent tablets of traditional Chinese medicine Xianganfang with fresh juice using a semi-solid 3D printer with three cartridge holders to seperate acid and alkali source by drug paste through model design to avoid sticking impact and premature effervescence during the tableting in the conventional preparation process. The powder of Xianganfang including fresh juice of Phyllanthus emblica and licorice extract was obtained by vacuum freeze-drying with 50% mannitol as cryoprotectant. Then, the formulation of 3D-printed effervescent tablets was investigated. Further 5% HPMC hydroalcoholic gel was mixed with sodium bicarbonate and freeze-dried Xianganfang powder to prepare alkali source and drug paste respectively while 30% PVP ethanol solution was mixed with tartaric acid to prepare acid source paste; these three pastes had good printability. The pastes of drug, acid, and alkali were loaded into three syringe cartridges separately and numbered as "3," "5," and "7," according to cartridge holders of the 3D printer, and printed in the order of "537,353,735" for separating acid and alkali by drug to avoid premature effervescence. And the basic printing parameters were optimized. The tablets were evaluated by the appearance, tablet weight variation, hardness, disintegration time, friability, pH, and stability. The physicochemical properties all conformed to the Chinese Pharmacopoeia 2020 edition. The content of the active ingredient gallic acid was 0.769 ± 0.019 mg/g. This study provided a new method to prepare effervescent tablets of traditional Chinese medicine with fresh juice using 3D printing technology.
Assuntos
Excipientes , Tecnologia Farmacêutica , Álcalis , Liberação Controlada de Fármacos , Excipientes/química , Pós , Comprimidos/química , Tecnologia Farmacêutica/métodosRESUMO
Conifers are considered to prefer to take up ammonium (NH4+ ) over nitrate (NO3- ). However, this conclusion is mainly based on hydroponic experiments that separate roots from soils. It remains unclear to what extent mature conifers can use nitrate compared to ammonium under field conditions where both roots and soil microbes compete for nitrogen (N). We conducted an in situ whole mature tree nitrogen-15 (15 N) labeling experiment (15 NH4+ vs 15 NO3- ) over 15 d to quantify ammonium and nitrate uptake and assimilation rates in four 40-yr-old monoculture coniferous plantations (Pinus koraiensis, Pinus sylvestris, Picea koraiensis and Larix olgensis, respectively). For the whole tree, 15 NO3- contributed 39% to 90% to total 15 N tracer uptake among four plantations during the study period. At day 3, the 15 NO3- accounted for 77%, 64%, 62% and 59% by Larix olgensis, Pinus koraiensis, Pinus sylvestris and Picea koraiensis, respectively. Our study indicates that mature coniferous trees assimilated nitrate as efficiently as ammonium from soils even at low soil nitrate concentration, in contrast to the results from hydroponic experiments showing that ammonium uptake dominated over nitrate. This implies that mature conifers can adapt to increasing availability of nitrate in soil, for example, under the context of globalization of N deposition and global warming.
Assuntos
Compostos de Amônio , Traqueófitas , Florestas , Nitratos/análise , Nitrogênio/análise , Solo , ÁrvoresRESUMO
The effects of nitrogen (N) deposition on forests largely depend on its fate after entering the ecosystem. While several studies have addressed the forest fate of N deposition using 15 N tracers, the long-term fate and redistribution of deposited N in tropical forests remains unknown. Here, we applied 15 N tracers to examine the fates of deposited ammonium ( NH 4 + ) and nitrate ( NO 3 - ) separately over 3 years in a primary and a secondary tropical montane forest in southern China. Three months after 15 N tracer addition, over 60% of 15 N was retained in the forests studied. Total ecosystem retention did not change over the study period, but between 3 months and 3 years following deposition 15 N recovery in plants increased from 10% to 19% and 13% to 22% in the primary and secondary forests, respectively, while 15 N recovery in the organic soil declined from 16% to 2% and 9% to 2%. Mineral soil retained 50% and 35% of 15 N in the primary and secondary forests, with retention being stable over time. The total ecosystem retention of the two N forms did not differ significantly, but plants retained more 15 NO 3 - than 15 NH 4 + and the organic soil more 15 NH 4 + than NO 3 - . Mineral soil did not differ in 15 NH 4 + and 15 NO 3 - retention. Compared to temperate forests, proportionally more 15 N was distributed to mineral soil and plants in these tropical forests. Overall, our results suggest that atmospherically deposited NH 4 + and NO 3 - is rapidly lost in the short term (months) but thereafter securely retained within the ecosystem, with retained N becoming redistributed to plants and mineral soil from the organic soil. This long-term N retention may benefit tropical montane forest growth and enhance ecosystem carbon sequestration.
Assuntos
Ecossistema , Nitrogênio , China , Florestas , Solo , ÁrvoresRESUMO
Nitrification is a crucial step in ecosystem nitrogen (N) cycling, but scaling up from plot-based measurements of gross nitrification to catchments is difficult. Here, we employed a newly developed method in which the oxygen isotope anomaly (Δ17O) of nitrate (NO3-) is used as a natural tracer to quantify in situ catchment-scale gross nitrification rate (GNR) for a temperate forest from 2014 to 2017 in northeastern China. The annual GNR ranged from 71 to 120 kg N ha-1 yr-1 (average 94 ± 10 kg N ha-1 yr-1) over the 4 years in this forest. This result and high stream NO3- loss (4.2-8.9 kg N ha-1 yr-1) suggest that the forested catchment may have been N-saturated. At the catchment scale, the total N output of 10.7 kg N ha-1 yr-1, via leaching and gaseous losses, accounts for 56% of the N input from bulk precipitation (19.2 kg N ha-1 yr-1). This result indicates that the forested catchment is still retaining a large fraction of N from atmospheric deposition. Our study suggests that estimating in situ catchment-scale GNR over several years when combined with other conventional flux estimates can facilitate the understanding of N biogeochemical cycling and changes in the ecosystem N status.
Assuntos
Ecossistema , Rios , China , Monitoramento Ambiental , Florestas , Nitratos , NitrogênioRESUMO
The individual identification of group-housed pigs plays an important role in breeding process management and individual behavior analysis. Recently, livestock identification methods based on the side view or face image have strict requirements on the position and posture of livestock, which poses a challenge for the application of the monitoring scene of group-housed pigs. To address the issue above, a Weber texture local descriptor (WTLD) is proposed for the identification of group-housed pigs by extracting the local features of back hair, skin texture, spots, and so on. By calculating the differential excitation and multi-directional information of pixels, the local structure features of the main direction are fused to enhance the description ability of features. The experimental results show that the proposed WTLD achieves higher recognition rates with a lower feature dimension. This method can identify pig individuals with different positions and postures in the pig house. Without limitations on pig movement, this method can facilitate the identification of individual pigs with greater convenience and universality.
Assuntos
Face , Sus scrofa , Animais , Monitorização Fisiológica , SuínosRESUMO
To explore the feasibility of preparing traditional Chinese medicine using 3 D printing technology and reduce warpage commonly occurs in large-size tablets, we investigated the prescription, warpage optimization and influence factors of 3 D printing Jiuxiang Jianpi Yangwei (JJY) tablets. The procedures used conformed to the requirements of the 2015 edition of the Chinese Pharmacopeia. The results of the prescription screening showed that 75% ethanol and HPMC (9%) could be adhesives. Meanwhile, stevia (0.5%) and citric acid (0.5%) improved the taste of the 3 D printed JJY tablets. To ensure the quality and appearance of the printed tablets, the best parameters were as follows: drying at room temperature, 40% of the filling density, a 3 mm model height, two outer ring numbers and a printing speed of 15 mm/s. The optimized printed tablets had a smooth appearance, suitable hardness, with the weight uniformity in accordance with the Pharmacopeia. We also prepared personalized JJY cartoon tablets (which contained images of a big-headed pig and a small yellow duck) which were designed to increase the compliance of children when taking their medications. In conclusion, this study reported that 3 D printing technology has great potential for preparing traditional Chinese medicines, and it provided guidance for 3 D printing tablets without warpage.
Assuntos
Química Farmacêutica , Medicamentos de Ervas Chinesas/administração & dosagem , Impressão Tridimensional , Tecnologia Farmacêutica , Estudos de Viabilidade , Dureza , Adesão à Medicação , Farmacopeias como Assunto , Medicina de Precisão , Comprimidos/normasRESUMO
With the rapid outbreak of COVID-19, traditional Chinese medicine(TCM) has been playing an active role against the epidemic. However, the screening of TCM is limited by the development cycle and laboratory conditions, which greatly limits the screening speed. This study established optimization docking models and virtual screening to discovery potential active herbs for the prevention and treatment of the novel coronavirus based on molecular docking technology. The crystal structures of 3 CL protease(Mpro) and papain-like protease(PLP) were obtained from PDB database and homologous modeling respectively, and were used to conduct virtual screening of TCMD 2009 database by CDOCKER program. The ingredients scored in the top 100 were selected respectively, and the candidate herbs were ranked by the numbers of hit molecules. Based on Mpro inhibitors screening, 12 322 potential active components were obtained, and the representative active components included aster pentapeptide A, ligustrazine, salvianolic acid B, etc., and Zingiberis Rhizoma Recens, Asteris Radix et Rhizoma, Notoginseng Radix et Rhizoma, Chuanxiong Rhizoma, Salviae Miltiorrhizae Radix et Rhizoma, Zingiberis Rhizoma, Dianthi Herba, Rhei Radix et Rhizoma, Cistanches Herba were obtained. While 11 294 potential active ingredients were obtained by PLP inhibitor screening, representative active ingredients included gingerketophenol, ginkgol alcohol, ferulic acid, etc., and Codonopsis Radix, Notopterygii Rhizoma et Radix, Zingiberis Rhizoma Recens, Ginkgo Semen, Chuanxiong Rhizoma, Trichosanthis Fructus, Paeoniae Radix Alba, Psoraleae Fructus, Sophorae Flavescentis Radix, Notoginseng Radix et Rhizoma, Angelicae Sinensis Radix were chosen. By combining the diagnosis and treatment scheme of Hunan province's and angiotensin converting enzyme 2(ACE2) inhibitors screening from literature, present study also discussed the rational application of candidate herbs to this epidemic situation. Trichosanthis Fructus obtained by PLP inhibitors screening and Fritillaria verticillata obtained by ACE2 inhibitors screening were parts of the Sangbei Zhisou Powder and Xiaoxianxiong Decoction, which might be applicable to the syndromes of cough and dyspnea. Rhei Radix et Rhizoma screened by Mpro and Trichosanthis Fructus screened by PLP were contained in Maxing Shigan Decoction and Xuanbai Chengqi Decoction, and could be applied to the syndromes of epidemic virus blocking lung. Mori Folium, Lonicerae Japonicae Flos and Forsythiae Fructus obtained by ACE2 inhibitors screening were included in the Sangju Decoction and Yinqiaosan, which might be applicable to the syndromes of warm pathogen attacking lung and cough and dyspnea. The results of this study are intended to provide a reference for the further development of traditional Chinese medicine to deal with the new epidemic.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Pneumonia Viral/tratamento farmacológico , Enzima de Conversão de Angiotensina 2 , COVID-19 , Avaliação Pré-Clínica de Medicamentos , Humanos , Simulação de Acoplamento Molecular , Pandemias , Peptidil Dipeptidase A , SARS-CoV-2 , Tratamento Farmacológico da COVID-19RESUMO
Since the outbreak of 2019-nCoV, the epidemic has developed rapidly and the situation is grim. LANCET figured out that the 2019-nCoV is closely related to "cytokine storm". "Cytokine storm" is an excessive immune response of the body to external stimuli such as viruses and bacteria. As the virus attacking the body, it stimulates the secretion of a large number of inflammatory factors: interleukin(IL), interferon(IFN), C-X-C motif chemokine(CXCL) and so on, which lead to cytokine cascade reaction. With the exudation of inflammatory factors, cytokines increase abnormally in tissues and organs, interfering with the immune system, causing excessive immune response of the body, resulting in diffuse damage of lung cells, pulmonary fibrosis, and multiple organ damage, even death. Arachidonic acid(AA) metabolic pathway is principally used to synthesize inflammatory cytokines, such as monocyte chemotactic protein 1(MCP-1), tumor necrosis factor(TNF), IL, IFN, etc., which is closely related to the occurrence, development and regression of inflammation. Therefore, the inhibition of AA metabolism pathway is benefit for inhibiting the release of inflammatory factors in the body and alleviating the "cytokine storm". Based on the pharmacophore models of the targets on AA metabolic pathway, the traditional Chinese medicine database 2009(TCMD 2009) was screened. The potential herbs were ranked by the number of hit molecules, which were scored by pharmacophore fit value. In the end, we obtained the potential active prescriptions on "cytokine storm" according to the potential herbs in the "National novel coronavirus pneumonia diagnosis and treatment plan(trial version sixth)". The results showed that the hit components with the inhibitory effect on AA were magnolignan â , lonicerin and physcion-8-O-ß-D-glucopy-ranoside, which mostly extracted from Magnoliae Officinalis Cortex, Zingiberis Rhizoma Recens, Lonicerae Japonicae Flos, Rhei Radix et Rhizoma, Salviae Miltiorrhizae Radix et Rhizoma, Scutellariae Radix, Gardeniae Fructus, Ginseng Radix et Rhizoma, Arctii Fructus, Dryopteridis Crassirhizomatis Rhizoma, Paeoniaeradix Rubra, Dioscoreae Rhizoma. Finally the anti-2019-nCoV prescriptions were analyzed to obtain the potential active prescriptions on AA metabolic pathway, Huoxiang Zhengqi Capsules, Jinhua Qinggan Granules, Lianhua Qingwen Capsules, Qingfei Paidu Decoction, Xuebijing Injection, Reduning Injection and Tanreqing Injection were found that may prevent 2019-nCoV via regulate cytokines. This study intends to provide reference for clinical use of traditional Chinese medicine to resist new coronavirus.
Assuntos
Ácido Araquidônico/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Citocinas/imunologia , Medicamentos de Ervas Chinesas/farmacologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Betacoronavirus , COVID-19 , Humanos , Medicina Tradicional Chinesa , Redes e Vias Metabólicas , Pandemias , SARS-CoV-2 , Tratamento Farmacológico da COVID-19RESUMO
The impacts of anthropogenic nitrogen (N) deposition on forest ecosystems depend in large part on its fate. However, our understanding of the fates of different forms of deposited N as well as the redistribution over time within different ecosystems is limited. In this study, we used the 15 N-tracer method to investigate both the short-term (1 week to 3 months) and long-term (1-3 yr) fates of deposited NH4+ or NO3- by following the recovery of the 15 N in different ecosystem compartments in a larch plantation forest and a mixed forest located in northeastern China. The results showed similar total ecosystem retention for deposited NH4+ and NO3- , but their distribution within the ecosystems (plants vs. soil) differed distinctly particularly in the short-term, with higher 15 NO3- recoveries in plants (while lower recoveries in organic layer) than found for 15 NH4+ . The different short-term fate was likely related to the higher mobility of 15 NO3- than 15 NH4+ in soils instead of plant uptake preferences for NO3- over NH4+ . In the long-term, differences between N forms became less prevalent but higher recoveries in trees (particularly in the larch forest) of 15 NO3- than 15 NH4+ tracer persisted, suggesting that incoming NO3- may contribute more to plant biomass increment and forest carbon sequestration than incoming NH4+ . Differences between the two forests in recoveries were largely driven by a higher 15 N recovery in the organic layer (both N forms) and in trees (for 15 NO3- ) in the larch forest compared to the mixed forest. This was due to a more abundant organic layer and possibly higher tree N demand in the larch forest than in the mixed forest. Leachate 15 N loss was minor (<1% of the added 15 N) for both N forms and in both forests. Total 15 N recovery averaged 78% in the short-term and decreased to 55% in the long-term but with increasing amount of 15 N label (re)-redistributed into slow turn-over pools (e.g., trees and mineral soil). The different retention dynamics of deposited NH4+ and NO3- may have implications in environmental policy related to the anthropogenic emissions of the two N forms.
Assuntos
Ecossistema , Florestas , China , Nitrogênio , Solo , ÁrvoresRESUMO
Denitrification removes fixed nitrogen (N) from the biosphere, thereby restricting the availability of this key limiting nutrient for terrestrial plant productivity. This microbially driven process has been exceedingly difficult to measure, however, given the large background of nitrogen gas (N2) in the atmosphere and vexing scaling issues associated with heterogeneous soil systems. Here, we use natural abundance of N and oxygen isotopes in nitrate (NO3 (-)) to examine dentrification rates across six forest sites in southern China and central Japan, which span temperate to tropical climates, as well as various stand ages and N deposition regimes. Our multiple stable isotope approach across soil to watershed scales shows that traditional techniques underestimate terrestrial denitrification fluxes by up to 98%, with annual losses of 5.6-30.1 kg of N per hectare via this gaseous pathway. These N export fluxes are up to sixfold higher than NO3 (-) leaching, pointing to widespread dominance of denitrification in removing NO3 (-) from forest ecosystems across a range of conditions. Further, we report that the loss of NO3 (-) to denitrification decreased in comparison to leaching pathways in sites with the highest rates of anthropogenic N deposition.
Assuntos
Desnitrificação , Ecossistema , Florestas , Microbiota , Nitratos/metabolismoRESUMO
CBR703 was reported to inhibit bacterial RNA polymerase (RNAP) and biofilm formation, considering it to be a good candidate for further optimization. While synthesized derivatives of CBR703 did not result in more-active RNAP inhibitors, we observed promising antibacterial activities. These again correlated with a significant cytotoxicity toward mammalian cells. Furthermore, we suspect the promising effects on biofilm formation to be artifacts. Consequently, this class of compounds can be considered unattractive as antibacterial agents.
Assuntos
Amidinas/farmacologia , Antibacterianos/farmacologia , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Hidroxilaminas/farmacologia , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Linhagem Celular , Escherichia coli/enzimologia , Escherichia coli/genética , Células HEK293 , Humanos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , RNA Bacteriano/biossíntese , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , Staphylococcus aureus/genética , Relação Estrutura-Atividade , Transcrição Gênica/efeitos dos fármacosRESUMO
BACKGROUND: The aqueous extract of the dried buds of Syzygium aromaticum (SAAE) have the potential to alleviate Helicobacter pylori infection, but the specific molecular mechanism has not been fully elucidated. PURPOSE: This study aimed to investigate the underlying mechanisms of SAAE on H. pylori pathogenicity. METHODS: The inhibitory kinetics and anti-H. pylori adhesive capacity assays were conducted to examine the effects of SAAE on the growth and adhesive capability of H. pylori. The H. pylori outer membrane vesicles (OMVs) were purified from the culture supernatant through high-speed centrifugation, filtration, and two rounds of ultracentrifugation. Their characteristics and protein composition were then identified using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and qualitative proteomics study. Subsequently, the effect of SAAE on the pathogenicity of H. pylori OMVs was investigated using the Griess reagent assay, enzyme-linked immunosorbent assay (ELISA), quantitative proteomics study, TEM, and western blotting assay. RESULTS: SAAE exhibited inhibitory effects on H. pylori growth and adhesion. The isolated H. pylori OMVs showed particle size of 27-242 nm and Zeta potential of -9.67 ± 0.53 mV. A total of 599 proteins were identified in the OMVs. Proteomics study indicated that the differential expressed proteins induced by OMVs with or without SAAE commonly enriched in P53 and autophagy pathways. Besides, SAAE counteracted the increased production of pro-inflammatory cytokines and attenuated the induction of cell autophagy caused by H. pylori OMVs. Furthermore, SAAE normalized the abnormal regulation of downstream targets (AIFM2 and IGFBP3) in the P53 signaling pathway caused by H. pylori OMVs. CONCLUSION: SAAE can inhibit the growth and adhesion of H. pylori, reduce the inflammation and autophagy induced by H. pylori OMVs, and combated the abnormal regulation of P53 signaling pathway caused by H. pylori OMVs. These findings may help elucidate the mechanisms through which SAAE reduces the pathogenicity of H. pylori.
Assuntos
Helicobacter pylori , Extratos Vegetais , Syzygium , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Syzygium/química , Humanos , Aderência Bacteriana/efeitos dos fármacos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Proteômica , Proteína Supressora de Tumor p53/metabolismo , Antibacterianos/farmacologia , Autofagia/efeitos dos fármacosRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Phellodendron chinense C.K.Schneid(P. chinense Schneid) is known in TCM as Huang Bo, is traditionally used to support gastrointestinal function and alleviate stomach-related ailments, including gastric ulcer bleeding and symptoms of gastroesophageal reflux disease. Helicobacter pylori (H. pylori) is classified by the WHO as a Group 1 carcinogen. However, the specific activity and mechanism of action of P. chinense Schneid against H. pylori infection remain unclear. It has been noted that Huangjiu processing may alter the bitter and cold properties of P. chinense Schneid, but its effect on antimicrobial activity requires further investigation. Additionally, it remains uncertain whether berberine is the sole antimicrobial active component of P. chinense Schneid. AIM OF STUDY: This study aims to elucidate the anti-H. pylori infection activity of P. chinense Schneid, along with its mechanism of action and key antimicrobial active components. MATERIALS AND METHODS: Phytochemical analysis was carried out by UPLC-MS/MS. HPLC was employed to quantify the berberine content of the extracts. Antimicrobial activity was assessed using the micro broth dilution method. Morphology was observed using SEM. The impact on urease activity was analyzed through in vitro urease enzyme kinetics. RT-qPCR was employed to detect the expression of virulence genes, including adhesin, flagellum, urease, and cytotoxin-related genes. The adhesion effect was evaluated by immunofluorescence staining and agar culture. RESULTS: P. chinense Schneid exhibited strong antimicrobial activity against both antibiotic-sensitive and resistant H. pylori strains, with MIC ranging from 40 to 160 µg/mL. Combination with amoxicillin, metronidazole, levofloxacin, and clarithromycin did not result in antagonistic effects. P. chinense Schneid induced alterations in bacterial morphology and structure, downregulated the expression of various virulence genes, and inhibited urease enzyme activity. In co-infection systems, P. chinense Schneid significantly attenuated H. pylori adhesion and urease relative content, thereby mitigating cellular damage caused by infection. Huangjiu processing enhanced the anti-H. pylori activity of P. chinense Schneid. Besides berberine, P. chinense Schneid contained seven other components with anti-H. pylori activity, with palmatine exhibiting the strongest activity, followed by jatrorrhizine. CONCLUSIONS: This study sheds light on the potential therapeutic mechanisms of P. chinense Schneid against H. pylori infection, demonstrating its capacity to disrupt bacterial structure, inhibit urease activity, suppress virulence gene transcription, inhibit adhesion, and protect host cells. The anti-H. pylori activity of P. chinense Schneid was potentiated by Huangjiu processing, and additional components beyond berberine were identified as possessing strong anti-H. pylori activity. Notably, jatrorrhizine, a core component of P. chinense Schneid, exhibited significant anti-H. pylori activity, marking a groundbreaking discovery.
Assuntos
Antibacterianos , Berberina , Helicobacter pylori , Phellodendron , Extratos Vegetais , Helicobacter pylori/efeitos dos fármacos , Phellodendron/química , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Berberina/farmacologia , Testes de Sensibilidade Microbiana , Urease/metabolismo , Humanos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologiaRESUMO
High reactive nitrogen (N) emissions due to anthropogenic activities in China have led to an increase in N deposition and ecosystem degradation. The Chinese government has strictly regulated reactive N emissions since 2010, however, determining whether N deposition has reduced requires long-term monitoring. Here, we report the patterns of N deposition at a rural forest site (Qingyuan) in northeastern China over the last decade. We collected 456 daily precipitation samples from 2014 to 2022 and analysed the temporal dynamics of N deposition. NH4+-N, NO3--N, and total inorganic N (TIN) deposition ranged from 10.5 ± 3.5 (mean ± SD), 6.1 ± 1.6, and 16.6 ± 4.7 kg N ha-1 year-1, respectively. Over the measurement period, TIN deposition at Qingyuan decreased by 55 %, whereas that in comparable sites in East Asia declined by 14-34 %. We used a random forest model to determine factors influencing the deposition of NH4+-N, NO3--N, and TIN during the study period. NH4+-N deposition decreased by 60 % because of decreased agricultural NH3 emissions. Furthermore, NO3--N deposition decreased by 42 %, due to reduced NOx emissions from agricultural soil and fossil fuel combustion. The steep decline in N deposition in northeastern China was attributed to reduced coal consumption, improved emission controls on automobiles, and shifts in agricultural practices. Long-term monitoring is needed to assess regional air quality and the impact of N emission control regulations.
RESUMO
Chasing the active impurity: In the validation of a screening hit it was discovered that a polymeric trace impurity was responsible for the biological activity. Such a side product can be formed with similar compounds. During the investigations it was discovered that the negatively charged macromolecule interacts very efficiently with the protein surface of E.â coli RNAP via electrostatic interactions.
Assuntos
Ácidos Carboxílicos/química , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Inibidores Enzimáticos/química , Ácidos Carboxílicos/metabolismo , Cromatografia Líquida de Alta Pressão , DNA/química , DNA/metabolismo , RNA Polimerases Dirigidas por DNA/isolamento & purificação , RNA Polimerases Dirigidas por DNA/metabolismo , Inibidores Enzimáticos/metabolismo , Escherichia coli/enzimologia , Ligação Proteica , Estrutura Terciária de Proteína , Eletricidade EstáticaRESUMO
Twenty-seven 1,5-disubstituted-pyridin-2(1H)-one derivatives were synthesized and evaluated for their anti-cancer and anti-fibrosis activity by A549 and NIH3T3 cell viability assays, respectively. To study the selectivity between the cancer and fibrosis cell lines, pharmacophore models (F1-F4) were built in advance for compounds with pyridin-2(1H)-one scaffold, which revealed the relationship between the occupation of the aromatic sub-site F4 and potent anti-cancer activity. The relationship between structure and anti-cancer activity for all target compounds is also reported herein: 1-Phenyl-5-((m-tolylamino)methyl)pyridine-2(1H)-one (22) displayed both potency and selectivity (IC50=0.13 mM) toward the A549 cell line through the inhibition of translation initiation, especially by eIF3a suppression, and can be treated as a lead for the design of novel eIF3a regulators and anti-lung cancer agents.
Assuntos
Antineoplásicos/farmacologia , Fator de Iniciação 3 em Eucariotos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Piridonas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Desenho de Fármacos , Fator de Iniciação 3 em Eucariotos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose/tratamento farmacológico , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/patologia , Camundongos , Células NIH 3T3 , Piridonas/síntese química , Piridonas/química , Relação Estrutura-AtividadeRESUMO
Since wetland construction projects are becoming more commonplace, meaningful follow-up studies are needed to evaluate how these systems change over time. To that end, the objective of our study was to examine the temporal changes in plant community composition and water chemistry in two constructed wetlands. We investigated two wetland sites that were constructed in 2003 in northern Otsego County, NY, a county that is largely dominated by agriculture. Site 1 was previously an active cow pasture and site 2 was previously a wet meadow surrounded by agricultural fields. No active plant introduction was made during the construction; however, both sites were located in areas with many remnant wetlands and were connected to through-flowing streams. In 2004 (Year 1) and 2010 (Year 7), the plant community composition and nitrogen retention were assessed. We found that both sites experienced site-wide declines in plant species richness, including the loss of upland and facultative upland species and the unanticipated loss of facultative wetland and some obligate species. We propose that high water levels, which, at their maximum depth were >1.5 m deeper than in Year 1, maintained by landowners in the years after the initial survey, may have been responsible for the unexpected loss of wetland species. We also found that site 1 exhibited considerable nitrogen retention in both Year 1 and Year 7; however, N concentrations were low at site 2 in both years.
Assuntos
Biodiversidade , Plantas/classificação , Áreas Alagadas , New York , Nitrogênio/análiseRESUMO
OBJECTIVE: To evaluate the results of the active follow-up among registered cancer patients in 2002 - 2005 in urban areas of Beijing. METHODS: A number of 63 997 cancer patients diagnosed during 2002 - 2005 were selected from the surveillance database of Beijing Office for Cancer Prevention and Control. By matching the identity information of the patients with the death surveillance database built by the vital statistic department in Beijing, 29 223 patients were confirmed to be alive.1149 cases were removed from the study due to lack of exact key variables, such as address and telephone numbers. 28 074 patients were, at last, included in the active follow-up study. The investigators and the inspectors, who accepted standard training program, investigated each patient's status of census register and survival condition by phone calling, household interview and visits at local police station or residential committee. The loss ratio of follow-up and the constituent ratio of the withdrawal reasons were calculated. RESULTS: Among the 28 074 patients selected in active follow-up, 21 696 patients were followed successfully; 1453 of whom didn't have the census register of Beijing, which accounted for 6.70%. Out of the other 20 243 Beijing residents, 4715 patients (23.29%) were already dead and 84.22% (3971/4715) of them replenished the failure to report by passive follow-up. Among all the 4715 dead cases, 4405 (93.43%) patients were died from cancer. The follow-up study helped to replenish the vital statistics in different districts, the ratio ranged from 4.87% and 8.85%. 6378 patients were withdrawn from the study. The loss ratio was 22.72% (6378/28 074), and the total loss ratio was 12.03% ((6378 + 1149)/(63 997 - 1453)). Of these withdrawal cases, 3041 (47.68%) were lost to follow-up in that the investigators can't find the patients or the relatives of the patients according to the registered phone number or address information. The other reasons included: the patients removed to other areas (1199 cases, 18.80%), the patients and their family members were temporarily not at home (127 cases, 1.99%), the patients and their family members rejected to answer the interview (292 cases, 4.58%), and other reasons (1719 cases, 26.95%). CONCLUSION: The method of active follow-up towards registered cancer patients can replenish the missing information which could not be collected from passive follow-up procedure; and therefore effectively improve the quality of data in cancer registration.
Assuntos
Neoplasias/epidemiologia , Neoplasias/prevenção & controle , China/epidemiologia , Seguimentos , Humanos , Neoplasias/mortalidade , Estatísticas VitaisRESUMO
Chitin, the major structural polysaccharide in arthropods such as insects and mites, is a linear polymer of N-acetylglucosamine units. The growth and development of insects are intimately coupled with chitin biosynthesis. The membrane-bound ß-glycosyltransferase chitin synthase is known to catalyze the key polymerization step of N-acetylglucosamine. However, the additional proteins that might assist chitin synthase during chitin biosynthesis are not well understood. Recently, fatty acid binding protein (Fabp) has been suggested as a candidate that interacts with the chitin synthase Krotzkopf verkehrt (Kkv) in Drosophila melanogaster. Here, using split-ubiquitin membrane yeast two-hybrid and pull-down assays, we have demonstrated that the Fabp-B splice variant physically interacts with Kkv in vitro. The global knockdown of Fabp in D. melanogaster using RNA interference (RNAi) induced lethality at the larval stage. Moreover, in tissue-specific RNAi experiments, silenced Fabp expression in the epidermis and tracheal system caused a lethal larval phenotype. Fabp knockdown in the wings resulted in an abnormal wing development and uneven cuticular surface. In addition to reducing the chitin content in the first longitudinal vein of wings, Fabp silencing also caused the loss of procuticle laminate structures. This study revealed that Fabp plays an important role in chitin synthesis and contributes to a comprehensive understanding of the complex insect chitin biosynthesis.
Assuntos
Quitina Sintase , Drosophila melanogaster , Acetilglucosamina , Animais , Quitina , Quitina Sintase/genética , Drosophila melanogaster/genética , Proteínas de Ligação a Ácido Graxo/genética , Insetos , Larva/genética , Interferência de RNA , Ubiquitinas/genéticaRESUMO
Resource integration of coal enterprises is conducive to reducing pollution and carbon emissions, thus alleviating environmental problems such as global warming. Government regulation has a great influence on enterprise behavior. Therefore, it is necessary to analyze the strategies of government and coal enterprises in resource integration. Based on the perspective of government regulation, this paper discusses how to guide and restrict coal enterprises to conduct resource integration behavior, and whether the government supervises this behavior. First, through empirical research, government regulations of coal enterprises are given practical policy implications. Second, using evolutionary game and simulation technology, from the perspective of government regulation, we explore the complex behavioral interaction mechanism between the dominant and inferior coal enterprises, the mechanism between the government and coal enterprises, and analyze the impact of key factors on the dynamic evolution process. Finally, the sensitivity analysis of the selected parameters is discussed in details, which provides useful decision-making suggestions for the government and enterprises. In addition, this paper further analyzes the impact of different government policies on coal enterprises' green innovation strategies. Results demonstrate that (1) when the power gap between enterprises is large, the probability of dominant enterprises choosing resource integration converges to 1, while the probability of inferior enterprises converges to 0. Therefore, government regulations are invalid for inferior enterprises; (2) the combination of government regulations can help improve the efficiency of coal enterprises' strategic choices. With the increase in the intensity of government rewards and punishments, the probability of enterprise resource integration evolves from 0 to 1; (3) excessive government regulations make the choice between the government and coal companies tend to swing, because the probability of the two is between 0 and 1. Therefore, excessive government regulations cannot effectively achieve resource integration and government regulation. (4) The government subsidy strategy is less effective than the government's pollution penalty strategy in promoting the green innovation of enterprises. Our research shows that the government should choose different policy combinations and intensities to regulate resource integration according to the market power of coal enterprises, which provides theoretical reference and practical guidance for the government to regulate corporate resource integration behavior.