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1.
Sci Rep ; 13(1): 4714, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949108

RESUMO

There are few reports of intravenous unit-dose tranexamic acid (TXA) on the relationship between visible blood loss (VBL) and hidden blood loss (HBL) in posterior lumbar interbody fusion (PLIF). Therefore, the objective of this randomized, prospective, double-blind, single center study was to investigate the effect of intravenous unit-dose TXA on VBL and HBL in patients who underwent PLIF. Among 100 patients, 11 were excluded due to failue to comply with the study, 1 was excluded due to non-conpliance with the study, and 88 were eligible for inclusion in the study. 46 patients who treated with PLIF received unit-dose of TXA (1 g/100 mL) intravenously 15 min before skin incision after general anesthesia (observation group) and 42 patients were given 100 mL of normal saline (control group). The operation time, intraoperative blood loss, postoperative drainage, VBL, HBL, blood transfusion rate, and adverse events were recorded in the two groups. Besides, activated partial prothrombin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen (FIB), platelets (PLT), red blood cells (RBC), hemoglobin (HB), hematocrit (HCT), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) on the 1st postoperative day; and RBC, HB, HCT, CRP, ESR on the 4th postoperative day were recorded. All 88 patients successfully completed the operation, the incision healed well, and there was no deep vein thrombosis of the lower extremity after operation. The intraoperative blood loss, postoperative drainage, VBL, HBL, and blood transfusion rate in the observation group were lower than those in the control group, and the differences were statistically significant (p < 0.05). There was no significant difference in operation time between the two groups (p > 0.05). There was no significant difference in postoperative APTT, PT, TT, FIB, PLT, RBC, HB, HCT, CRP and ESR between the two groups (p > 0.05). Intravenous unit-dose TXA is safe and feasible in PLIF, and it can effectively reduce perioperative VBL and HBL.


Assuntos
Antifibrinolíticos , Hemostáticos , Ácido Tranexâmico , Humanos , Antifibrinolíticos/uso terapêutico , Estudos Prospectivos , Perda Sanguínea Cirúrgica/prevenção & controle , Proteína C-Reativa , Hemorragia Pós-Operatória/tratamento farmacológico
2.
Mar Drugs ; 21(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36827147

RESUMO

Fucoxanthin and fatty acids are active substances that are beneficial to the growth and immunity of humans and aquatic animals. However, relatively few species have been exploited for fucoxanthin and fatty acids in the industry. At the same time, due to its low extract content, poor stability, high production cost, and serious seasonal and regional limitations, the industry cannot normally meet the greater demand of the international market. Therefore, this experiment seeks to improve the fucoxanthin and fatty acid content of C. weissflogii by adjusting the nitrogen concentration in the culture medium. It was found that when the nitrogen concentration was 150 mg L-1, the cell number was 1.5 × 106 cell mL-1, and the average biomass was 0.75 g L-1. The mean value of carotenoid concentration was 2.179 mg L-1. The average concentration of fucoxanthin was 1.547 mg g-1. When the nitrogen concentration was 75 mg L-1, the fatty acid content reached its highest. By adjusting the concentration of nitrogen, the contents of fucoxanthin and fatty acids were increased. The results provided a theoretical basis for commercial extraction of fucoxanthin and fatty acids and further promoted the industrialization of fucoxanthin and fatty acids.


Assuntos
Diatomáceas , Ácidos Graxos , Animais , Humanos , Ácidos Graxos/farmacologia , Xantofilas/farmacologia , Carotenoides/farmacologia , Nitrogênio/farmacologia
4.
Heliyon ; 8(11): e11808, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36458293

RESUMO

Aeromagnetic survey of multi-rotor UAV is widely used in small and medium-sized mineral resources survey, engineering investigation, non-explosive detection and other fields due to its advantages of high safety, low cost and convenient operation. The original data of UAV aeromagnetic survey includes interference from external environment, interference from UAV platform and interference from airborne electromagnetic equipment. The interference is mainly shown as striping anomaly along the direction of the survey line in the aeromagnetic anomaly map, which affects the accuracy of aeromagnetic compensation and information detection of geological anomaly body, thus affecting the accuracy of interpretation of geological anomaly body. In this paper, the algorithm of Variational Modal Decomposition (VMD) is introduced to filter and preprocess the aeromagnetic data to obtain high quality aeromagnetic data. At the same time, the source and characteristics of the errors are predicted according to the interference size and spectrum characteristics of the Modal function errors, which provides a reference for the optimization of aeromagnetic system.

5.
Environ Sci Technol ; 56(16): 11256-11265, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35900360

RESUMO

Increasing worldwide demand for beef products promotes international beef trade. Cattle raising and beef products as significant sources of methane (CH4) emissions have received widespread concerns. However, the factors driving CH4 emissions embodied in the global beef trade have not been quantified. Here, we evaluate international beef trade-induced CH4 emissions and assess the contribution of the five driving factors to changes in CH4 emissions embodied in the beef trade from 2000 to 2018. We show that driven by increasing population and meat demands, the global beef trade-induced CH4 emissions increased continuously in the past two decades, with total emissions of 9337.3 Gg in 2018. The drivers that could potentially reduce trade-related emissions are emission intensities in beef exporting countries and beef importing countries' selections of their beef suppliers. Together, these two driving factors reduced CH4 emissions by 923.5 Gg from 2012 to 2018. Results suggest that efforts should be made to reduce the emission intensity via improving cattle feed and feeding practices in beef exporting countries. Beef importing countries could also contribute to CH4 emission reduction by selecting those beef exporting countries with low emission intensities.


Assuntos
Comportamento Alimentar , Metano , Animais , Bovinos
6.
Environ Sci Technol ; 56(11): 6978-6987, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35271270

RESUMO

Urbanization perturbs air pollutants from a dynamic and thermodynamic perspective, which has inspired extensive investigations in China due to rapid urban land expansion in the past four decades. However, knowledge gaps remain in the long-term and nationwide responses to air pollutants to urbanization. The evolution of tropospheric ozone associated with urban land expansion across China was assessed from 1980 to 2017 using a coupled WRF-Chem model based on a recently updated land use change (LUC) data set. The results revealed that urban-land expansion drove growing ozone trends for this period and contributed about 3-9% to its summer maximum concentrations during the 2010s in major urban agglomerations across China. The association between a long-term change in summer O3 concentrations and LUC after excluding the effect of precursor emissions and meteorological conditions and causes of interannual (short-term) variations in O3 concentrations induced by urban-land expansion were also explored by examining the relationships between ozone fluctuations and meteorological variables.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental/métodos , Ozônio/análise
7.
Environ Pollut ; 298: 118859, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35063539

RESUMO

Rapid urbanization and industrialization in the eastern seaboard region of China enhance the widespread use of organophosphorus flame retardants (OPFRs). The present study set up a coupled WRF-CMAQ-SMOKE and multi-compartment exchange modeling framework to assess the environmental fate and cycling of OPFRs and their contamination in the Bohai and Yellow Seas' marine food web. The framework predicts meteorological conditions, optimized air emissions, and concentrations of OPFRs in air, seawaters, marine sediment, and the food web. The model was implemented to simulate the temporal and spatial fluctuations of Tris (2-chloroisopropyl) phosphate (TCPP), the most dominant congener of OPFRs in China, in the Bohai and the Yellow Sea ecosystems on a spatial resolution of 10 km. Results revealed the effects of source proximity, atmospheric transport and deposition, and the changes in meteorology on TCPP's temporal-spatial distribution across different areas of coastal waters. The model also captures TCPP levels in commercial fish species in the Bohai Sea. The detailed temporal-spatial characteristics of TCPP with the mesoscale resolution provide useful information and a new tool for the environmental and health consequences of mariculture, urban and industrial emission mitigation in coastal regions for emerging chemicals, and fishery industry development.


Assuntos
Retardadores de Chama , Animais , China , Ecossistema , Monitoramento Ambiental , Retardadores de Chama/análise , Oceanos e Mares , Organofosfatos/análise , Compostos Organofosforados/análise
8.
Zootaxa ; 5027(3): 301-331, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34811168

RESUMO

Deleaster Erichson is an oxyteline genus with only 12 species worldwide, but its members have very distinctive appearance and bear primitive characters, which are particularly critical in understanding the evolution of Oxytelinae. Here we review the species in China and provide a new record species, Deleaster bactrianus Semenov, to Chinese fauna of this genus. Additionally, we describe the first complete mitochondrial genome of Deleaster.


Assuntos
Besouros , Genoma Mitocondrial , Distribuição Animal , Animais , China , Besouros/genética
9.
iScience ; 24(11): 103255, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34755094

RESUMO

The bioaccumulation of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), known as dioxins, in fatty meat is one of primary pathways of entry into the human body, but levels of human exposure to dioxins in fatty meat subject to global trade are unknown. We show high dioxin estimated dietary intake (EDI) via pork consumption in Europe, the United States, and China, owing to stronger dioxin environmental contamination and high pork consumption in these countries. The dioxin risk transfer embodied in pork trade is mostly significant in high-latitude countries and regions of Canada, Russia, and Greenland because these regions with low dioxin environmental levels import large amounts of pork meat from more severely dioxin-contaminated Europe and the United States. We demonstrate that global pig feed trading decreases the exposure of pork consumers to dioxins via the import of feed from countries with low dioxin environmental contamination by pig breeding countries.

10.
Sci Total Environ ; 795: 148807, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34237535

RESUMO

To stop the spread of COVID-19 (2019 novel coronavirus), China placed lockdown on social activities across China since mid-January 2020. The government actions significantly affected emissions of atmospheric pollutants and unintentionally created a nationwide emission reduction scenario. In order to assess the impacts of COVID-19 on fine particular matter (PM2.5) levels, we developed a "conditional variational autoencoder" (CVAE) algorithm based on the deep learning to discern unsupervised PM2.5 anomalies in Chines cities during the COVID-19 epidemic. We show that the timeline of changes in number of cities with unsupervised PM2.5 anomalies is consistent with the timeline of WHO's response to COVID-19. Using unsupervised PM2.5 anomaly as a time node, we examine changes in PM2.5 before and after the time node to assess the response of PM2.5 to the COVID-19 lockdown. The rate of decrease of PM2.5 around the time node in northern China is 3.5 times faster than southern China, and decreasing PM2.5 levels in southern China is 3.5 times of that in northern China. Results were also compared with anomalous PM2.5 occurring in Chinese's Spring Festival from 2017 to 2019, PM2.5 anomalies during around Chinese New Year in 2020 differ significantly from 2017 to 2019. We demonstrate that this method could be used to detect the response of air quality to sudden changes in social activities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Epidemias , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise , SARS-CoV-2
11.
Zootaxa ; 4861(1): zootaxa.4861.1.2, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33055867

RESUMO

The Anotylus nitidifrons group (Coleoptera: Staphylinidae: Oxytelinae) is studied and five new species are described from China: Anotylus sculptifrons Wang Zhou, sp. nov. (Hubei, Yunnan), A. corrugifrons Wang Zhou, sp. nov. (Guangxi), A. applanatifrons Wang Zhou, sp. nov. (Zhejiang), A. declivisculptilis Wang Zhou, sp. nov. (Guangxi), A. scabrifrons Wang Zhou, sp. nov. (Sichuan). The taxonomic history of Anotylus nitidifrons group is briefly reviewed and another Chinese species is redescribed. Color plates and line-drawing are provided for all new species and other two species known from China. A key to the Chinese species of Anotylus nitidifrons group is included in the paper.


Assuntos
Besouros , Distribuição Animal , Estruturas Animais , Animais , China , Tamanho do Órgão
12.
Sci Total Environ ; 722: 137755, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32199359

RESUMO

PKU-FUEL is a recently developed gridded global emission inventory for multiple air pollutants that uses a bottom-up approach. The inventory includes data collected monthly for the period of 1960 to 2014 and at a 0.1° × 0.1° latitude/longitude resolution. In an effort to evaluate and improve this emission inventory, the PKU-FUEL Sulfur Dioxide (SO2) emission inventory was compared to other currently available and widely used global SO2 emission inventories constructed based on bottom-up and top-down approaches, including CEDS and OMI-HTAP. While PKU-FUEL is capable of capturing SO2 emissions across the globe and particularly in Asia, it misses 41 industrial point sources globally, accounting for 9.3% of Ozone Monitoring Instrument (OMI) remote sensing-measured industrial point sources. Most of these missing point sources are identified in Latin America, the Middle East (~60%), and some remote places. To improve the PKU-FUEL SO2 inventory, we applied OMI-measured emissions to sources missing from PKU-FUEL. GEOS-Chem model simulations were performed to evaluate original and improved PKU-FUEL SO2 inventories against measured SO2 concentrations across the world. Results were further compared to GEOS-Chem modeled SO2 concentrations using the CEDS inventory. We show that the modeled SO2 concentrations determined using both CEDS and improved PKU-FUEL inventories to a large extent corroborate sampled data and that the improved PKU-FUEL performs better for those regions lacking monitoring data.

13.
Environ Pollut ; 261: 114186, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32092627

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are formed by the incomplete combustion of fossil fuels and forest or biomass burning. PAHs undergo long-range atmospheric transport, as evidenced by in situ observations across the Arctic. However, monitored atmospheric concentrations of PAHs indicate that ambient PAH levels in the Arctic do not follow the declining trend of worldwide anthropogenic PAH emissions since the 2000s, suggesting missing sources of PAHs in the Arctic or other places across the Northern Hemisphere. To trace origins and causes for the increasing trend of PAHs in the Arctic, the present study reconstructed PAH emissions from forest fires in the northern boreal forest derived by combining forest carbon stocks and MODIS burned area. We examined the statistical relationships of forest biomass, MODIS burned area, emission factors, and combustion efficiency with different PAH congeners. These relationships were then employed to construct PAH emission inventories from forest biomass burning. We show that for some PAH congeners, for example, benzo[a]pyrene (BaP)-the forest-fire-induced air emissions are almost one order of magnitude higher than previous emission inventories in the Arctic. A global-scale atmospheric chemistry model, GEOS-Chem, was used to simulate air concentrations of BaP, a representative PAH congener primarily emitted from biomass burning, and to quantify the response of BaP to wildfires in the northern boreal forest. The results showed that BaP emissions from wildfires across the northern boreal forest region played a significant role in the contamination and interannual fluctuations of BaP in Arctic air. A source-tagging technique was applied in tracking the origins of BaP pollution from different northern boreal forest regions. We also show that the response of BaP pollution at different Arctic monitoring sites depends on the intensity of human activities.


Assuntos
Poluentes Atmosféricos/análise , Incêndios , Hidrocarbonetos Policíclicos Aromáticos/análise , Regiões Árticas , Monitoramento Ambiental , Taiga
14.
Zootaxa ; 4351(1): 1-79, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29245535

RESUMO

The Anotylus sculpturatus species group is one of the relatively well-defined assemblages within the very large genus Anotylus Thomson, 1859 of the subfamily Oxytelinae (Coleoptera: Staphylinidae). This paper briefly examines the species group classification of the genus Anotylus and concentrates mainly on the taxonomy of Anotylus sculpturatus group. The paper reviews the Chinese fauna of 13 species, with seven new species described here: Anotylus benisculptilis sp. nov., A. nigelisculptilis sp. nov. and A. brevisculptilis sp. nov. from Sichuan, A. varisculptilis sp. nov. from Yunnan and Sichuan, A. nitelisculptilis sp. nov. from Sichuan, Ningxia, Gansu and Shaanxi, A. rectisculptilis sp. nov. from Zhejiang, and A. extrasculptilis sp. nov. from Yunnan. Lectotypes are designated for Anotylus chinkiangensis (Bernhauer, 1938) and A. subsericeus (Bernhauer, 1938). Color figures and line-drawings are provided for all the new species and most of the earlier known species from China. A preliminary key to the species groups of Anotylus and a key to the species of Anotylus sculpturatus group, mainly focused on Chinese fauna, are also included in the paper, so as to benefit the classification and identification in the future.


Assuntos
Besouros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Tamanho do Órgão
15.
Angew Chem Int Ed Engl ; 54(46): 13655-8, 2015 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-26457665

RESUMO

The formation of carbon-carbon bonds through the functionalization of aromatic carbon-nitrogen bonds is a highly attractive synthetic strategy in the synthesis of aromatic molecules. In this paper, we report a novel aromatic carbon-nitrogen bond functionalization reaction by using a simple dearomatization strategy. Through this process para-substituted anilines serve as a potential aryl source in the construction of a range of functionalized aromatic molecules, such as quaternary carbon centers, α-keto esters, and aldehydes.

16.
Biochem Biophys Res Commun ; 459(4): 617-22, 2015 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-25749344

RESUMO

Despite the effectiveness of the anti-CD20 chimeric antibody (mAb), rituximab, in treating B-cell lymphomas, its efficacy remains variable and often modest. Hu8E4 is an anti-CD20 humanized antibody which exhibits markedly higher antitumor activity compared with rituximab. Previous studies have indicated that rituximab and almost all known anti-CD20 murine mAbs recognize the A170/P172 motif within the large extracellular loop of CD20. In this study, we demonstrated that hu8E4 also recognized the A170/P172 motif, suggesting that the epitopes recognized by rituximab and hu8E4 are very similar. Based on this, three single mutations (D57E, Y102K and Y102T) at the heavy chain variable region that can improve the affinity of rituximab were transferred to hu8E4. The results showed that D57E and Y102T but not Y102K successfully enhanced the binding of hu8E4 to CD20. Out of these hu8E4 mutants, hu8E4D57E exhibited the highest affinity. The in vitro and in vivo antitumor activity of hu8E4D57E was further investigated. Our data indicated that hu8E4D57E was as effective as hu8E4 in mediating CDC and inducing apoptosis in B-lymphoma cells, but it was more potent in ADCC than hu8E4. Importantly, hu8E4D57E was shown to be significantly more effective than Hu8E4 in prolonging the survival of SCID mice bearing disseminated B-lymphoma cells, suggesting that it might be a promising therapeutic agent for B-cell lymphomas. Moreover, this study also suggests that the mutations that can improve the affinity of rituximab may be transferred to other anti-CD20 murine mAbs to enhance their binding to CD20.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Antígenos CD20/imunologia , Epitopos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais Humanizados/genética , Citotoxicidade Celular Dependente de Anticorpos , Apoptose , Epitopos/química , Humanos , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Homologia de Sequência de Aminoácidos
17.
Org Lett ; 14(14): 3596-9, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22780335

RESUMO

The oxidative dearomatization of para-substituted o-alkynylanilines afforded 2-alkynyl cyclohexadienimines, which can act as active substrates for reaction with electron-rich styrenes. The reaction is metal-controlled. Bi(OTf)3-catalyzed reactions afforded 3,4-dihydro-cyclopenta[c,d]indoles, and AgOTf-catalyzed reactions provided tricyclic pyrrole derivatives.

18.
J Org Chem ; 75(5): 1760-3, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20136158

RESUMO

An efficient aqueous oxidative cyclization mediated by the combination of iodosobenzene with tetra-(n-butyl)ammonium iodide provides a new convenient and useful route to functionalized fused dihydrofuran derivatives in moderate to excellent yields with high diastereoselectivities.


Assuntos
Furanos/síntese química , Iodo/química , Ciclização , Furanos/química , Modelos Moleculares , Estrutura Molecular , Oxirredução , Estereoisomerismo , Relação Estrutura-Atividade , Água/química
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