Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 290
Filtrar
1.
J Hazard Mater ; 424(Pt B): 127441, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34673396

RESUMO

The natural ecosystem will continually deteriorate for decades by the leakage of Cs and Sr isotopes. The exploration of the new materials or techniques for the efficient treatment of radioactive wastewater is critically important. In this study, a dielectric barrier discharge (DBD) configuration was constructed to operate the non-thermal plasma (NTP). The NTP was incorporated into the synthesis of polyaluminum chloride (PAC) in two different procedures to intensify the synthesis of PAC (NTP-PAC) and enhance the further removal of Cs and Sr from wastewater. The employment of NTP in two procedures both had significantly changed the physicochemical characteristics of PAC materials, which facilitated the further adsorption application of NTP-PAC on the treatment of Cs+ and Sr2+. Different molecular, morphological, and adsorption characteristics were confirmed to the NTP-PAC materials. The heterogeneous adsorption of the NTP-PAC can be appropriately fitted by both the pseudo-first-order kinetic model and the Elovich model. Both physisorption and chemisorption reaction mechanisms were ensured for the heterogeneous adsorption of the NTP-PAC material towards Cs+ and Sr2+, which guaranteed the excellent adsorption performance of NTP-PAC materials compared to PAC. The electron collisions caused by NTP with alum pulp created highly reactive growth precursors and intensified the nucleation and hydrolysis polymerization of PAC. The employment of NTP explicitly broadens the reaction pathways between PAC and cationic contaminants in the aqueous environment, which expands the application area of PAC materials in environmental sustainability.

2.
Synth Syst Biotechnol ; 6(4): 292-301, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34584996

RESUMO

Spinosyns are natural broad-spectrum biological insecticides with a double glycosylated polyketide structure that are produced by aerobic fermentation of the actinomycete, Saccharopolyspora spinosa. However, their large-scale overproduction is hindered by poorly understood bottlenecks in optimizing the original strain, and poor adaptability of the heterologous strain to the production of spinosyn. In this study, we genetically engineered heterologous spinosyn-producer Streptomyces albus J1074 and optimized the fermentation to improve the production of spinosad (spinosyn A and spinosyn D) based on our previous work. We systematically investigated the result of overexpressing polyketide synthase genes (spnA, B, C, D, E) using a constitutive promoter on the spinosad titer in S. albus J1074. The supply of polyketide synthase precursors was then increased to further improve spinosad production. Finally, increasing or replacing the carbon source of the culture medium resulted in a final spinosad titer of ∼70 mg/L, which is the highest titer of spinosad achieved in heterologous Streptomyces species. This research provides useful strategies for efficient heterologous production of natural products.

3.
J Sep Sci ; 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34514725

RESUMO

Red and yellow pigments are the major ingredients of safflower, often used to color food and cosmetics. Carthamin was the main component of red pigment and hydroxysafflor yellow A and anhydrosafflower yellow B were representative components of yellow pigment. Plant metabolomics and semi-quantitative analysis were used to analyze the changes of pigment composition during the blooming period, especially these characteristic components. Carthamin, hydroxysafflor yellow A, anhydrosafflower yellow B, and other components were screened out as differential metabolites based on plant metabolomics. Then semi-quantitative analysis was used to quantify these three representative components of pigments. Experimental results showed that the content of pigments has dynamic changes along with flowering, in the early blooming period, yellow pigment accumulated much and red pigment was low in content. In the middle period, the accumulation rate of the yellow pigment slowed down and content was stabilized. In the next step, the content of yellow pigments gradually decreased, and the content of red pigments gradually increased. Later, the level of yellow pigment decreased significantly, and the accumulation rate of red pigment increased significantly. Last, the appearance color of safflower was red, with yellow parts barely visible, and accumulation of red pigment was the highest and of the yellow pigment was the lowest in content.

4.
Chemosphere ; 287(Pt 1): 132049, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34474390

RESUMO

Novel pre-coagulation-sedimentation integrated with ultraviolet activated sodium percarbonate (SPC) (Fe(III)-UV/SPC) processes are promising methods for ultrafiltration (UF) pretreatment to ensure the safety of rural drinking water and mitigate UF membrane fouling. The process of surface water purification using the integrated coagulation-advanced oxidation processes (AOPs)-UF system relies on the idea that pre-coagulation can remove hydrophobic macromolecular organic compounds, thus facilitating the oxidation of hydrophilic molecules or medium-sized macromolecules to improve the utilization efficiency of free radicals in AOPs. Compared with the UV/SPC process, the removal rates of UV254 and DOC in the Fe(III)-UV/SPC process (Fe(III) = 0.1 mM, SPC = 0.5 mM) were increased from 87.39 % to 41.45 %-93.56 % and 52.51 %, respectively. Furthermore, the dosage of SPC was reduced from 0.75 mM in UV/SPC process to 0.5 mM due to effects of pre-coagulation. The free radical quenching experiment showed that a significant radical sink of reactions with organic contaminants was formed by •OH and CO3•- in the UV/SPC process, rather than a single specific radical. The destruction of the cake layer structure, reduction in contaminant concentration, and appearance of many permeable holes on the membrane surface were the main reasons for the alleviation of UF membrane fouling. Finally, the trans-membrane pressure and reversible membrane resistance decreased from 22.33 kPa to 3.68 × 1011 m-1 to 18.28 kPa and 0.93 × 1011 m-1, respectively. These results provide new insights into the behavior of membrane fouling control and offer technical references for the long-term stable operation of the UF process.

5.
Chemosphere ; 283: 131180, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34467942

RESUMO

The raw water distribution systems (RWDSs) play key roles in urban water supply systems. The changes of disinfection byproducts (DBPs) precursors of trihalomethanes (THMs), haloacetic acids (HAAs) and halogenated acetaldehydes (HALs) in the RWDS in Taihu Basin were investigated by formation potentials. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) method and 454-pyrosequencing were employed to study the variation of molecular characteristics of low molecular weight-dissolved organic matter (LMW-DOM) and microbial communities of pipeline biofilms respectively, which played crucial roles in the variation of DBPs precursors. The results showed that both DBPs precursors and the molecular characteristics of LMW-DOM in the RWDS had changed. Moreover, the LMW-DOM could be an indicator due to the good positive correlation with precursors of HAAs and HALs. Specifically, the LMW-DOM showed continuous accumulation in the RWDS. The LMW-DOM tended to possess higher m/z and more CH2 or long alkyl chains while pre-chlorination controlled this trend. The LMW-DOM in the pre-chlorinated pipe section also possessed higher saturation. Additionally, lignins served as an important part of DBPs precursors and dominated the LMW-DOM. The microbial diversity decreased in the RWDS, and the abundance and diversity of the microbial community in the pre-chlorinated section were significantly lower than those in the no-chlorinated section. Finally, most DBPs precursors had positive correlation with dominant phylum and genus in RWDS. This study reveals variation of DBPs precursors, LMW-DOM and microbial pipeline biofilms as well, and provide important data for further research on raw water safety and stability in RWDSs.


Assuntos
Desinfetantes , Microbiota , Poluentes Químicos da Água , Purificação da Água , Desinfetantes/análise , Desinfecção , Halogenação , Trialometanos/análise , Água , Poluentes Químicos da Água/análise
6.
Cardiovasc Toxicol ; 21(12): 984-999, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34424481

RESUMO

Novel insights into epigenetic control of cardiac fibrosis are now emerging. Cardiac fibroblasts (CFs) activation into myofibroblasts and the production of extracellular matrix (ECM) is the key to cardiac fibrosis development, but the specific mechanism is not fully understood. In the present study, we found that DNMT1 hypermethylation reduces the expression of microRNA-152-3p (miR-152-3p) and promotes Wnt1/ß-catenin signaling pathway leading to CFs proliferation and activation. Cardiac fibrosis was produced by ISO, and the ISO was carried out according to the method described. CFs were harvested and cultured from SD neonatal rats and stimulated with TGF-ß1. Importantly, DNMT1 resulted in the inhibition of miR-152-3p in activated CFs and both DNMT1 and miR-152-3p altered Wnt/ß-catenin downstream protein levels. Over expression of DNMT1 and miR-152-3p inhibitors promotes proliferation of activating CFs. In addition, decreased methylation levels and over expression of miR-152-3p inhibited CFs proliferation. We determined that DNMT1 can methylate to miR-152-3p and demonstrated that expression of miR-152-3p inhibits CFs proliferation by inhibiting the Wnt1/ß-catenin pathway. Our results stand out together DNMT1 methylation regulates miR-152-3p to slow the progression of cardiac fibrosis by inhibiting the Wnt1/ß-catenin pathway.

7.
Nat Commun ; 12(1): 4669, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344873

RESUMO

Diseases are a manifestation of how thousands of proteins interact. In several diseases, such as cancer and Alzheimer's disease, proteome-wide disturbances in protein-protein interactions are caused by alterations to chaperome scaffolds termed epichaperomes. Epichaperome-directed chemical probes may be useful for detecting and reversing defective chaperomes. Here we provide structural, biochemical, and functional insights into the discovery of epichaperome probes, with a focus on their use in central nervous system diseases. We demonstrate on-target activity and kinetic selectivity of a radiolabeled epichaperome probe in both cells and mice, together with a proof-of-principle in human patients in an exploratory single group assignment diagnostic study (ClinicalTrials.gov Identifier: NCT03371420). The clinical study is designed to determine the pharmacokinetic parameters and the incidence of adverse events in patients receiving a single microdose of the radiolabeled probe administered by intravenous injection. In sum, we introduce a discovery platform for brain-directed chemical probes that specifically modulate epichaperomes and provide proof-of-principle applications in their use in the detection, quantification, and modulation of the target in complex biological systems.


Assuntos
Sistema Nervoso Central/metabolismo , Chaperonas Moleculares/metabolismo , Mapeamento de Interação de Proteínas/instrumentação , Proteoma/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Glioblastoma/diagnóstico , Glioblastoma/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Camundongos , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Sondas Moleculares/farmacologia , Sondas Moleculares/uso terapêutico , Tomografia por Emissão de Pósitrons
8.
J Surg Oncol ; 124(5): 767-779, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34263466

RESUMO

BACKGROUND AND AIMS: In this study, we aimed to develop a convenient web-based calculator to predict the overall survival (OS) of patients with Stage I esophageal cancer (EC). METHODS: Data of 1664 patients, between 2004 and 2015, were extracted from the Surveillance, Epidemiology, and End Results database. Least absolute shrinkage and selection operator regression was employed to sift variables; subsequently, Cox proportional hazards regression model was built. We applied the enhanced bootstrap validation to appraise the discrimination and calibration of the model. Clinical benefit was measured using decision curve analysis (DCA). Thereafter, a web-based calculator based on the model, which could be used to predict the 1-, 3-, and 5-year OS rates, was developed. RESULTS: Race, age, histologic type, grade, N stage, and therapeutic methods were selected. C-indices of the prediction model in the training and validation groups were 0.726 (95% confidence interval [CI], 0.679-0.773) and 0.724 (95% CI, 0.679-0.769), respectively. Calibration curves showed good agreement between the groups. The DCA demonstrated that the prediction model is clinically useful. CONCLUSIONS: The prediction model we developed showed a good performance in calculating the OS rates in patients with Stage I EC. The web-based calculator is available at https://championship.shinyapps.io/dynnomapp/.


Assuntos
Neoplasias Esofágicas/mortalidade , Internet/estatística & dados numéricos , Nomogramas , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Programa de SEER , Taxa de Sobrevida
9.
J Anat ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34235729

RESUMO

The rat is frequently used as a model to study the characteristics, aetiology and pathology of the Achilles tendon. However, though the structure of the human Achilles tendon has been extensively investigated, the anatomical structure of the rat Achilles tendon remains unclear, which impedes the ability to use rats to study Achilles tendinopathy. The purpose of this study was to reveal the structure of the rat Achilles tendon and to explore its similarities with the human Achilles tendon through an anatomical dissection of 80 rat Achilles tendons (40 female, 40 male). This study found that the subtendons of the rat Achilles tendon originating from the triceps surae muscle were twisted, and each subtendon also had its own torsion. The extent of these two types of torsion could be very different between rats. Alterations in this torsion may result in distinct stress fields in the Achilles tendon, which may play a critical role in the pathogenesis of Achilles tendinopathy. This study provides an important basis to support the use of rats as model animals to investigate the characteristics of the human Achilles tendon and Achilles tendinopathy.

10.
J Clin Lab Anal ; 35(8): e23859, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34251052

RESUMO

BACKGROUND: This study aimed to evaluate the urate-lowering effects of Yi-Suan-Cha and explore its underlying mechanisms in experimental hyperuricemia induced in rats. METHODS: Forty-eight male SD rats were randomly allocated into normal control, model, allopurinol, benzbromarone, low-dose Yi-Suan-Cha (0.2 g/ml), and high-dose Yi-Suan-Cha (0.4 g/ml) groups (n = 8 rats per group). Rat models of hyperuricemia were established through intragastric administration of adenine 25 mg/kg + potassium oxalate 300 mg/kg for 3 weeks. After the last administration, serum uric acid, creatinine, and urea nitrogen levels were measured. Renal histopathology was observed by hematoxylin-eosin staining. Xanthine oxidase level in serum and liver homogenates was measured by ELISA. The protein and mRNA expression of URAT1, ABCG2, OAT1, and GLUT9 in the kidney was detected by Western blotting and RT-PCR, respectively. RESULTS: The serum uric acid levels were significantly lowered in all medication groups than in the model group. The benzbromarone and both Yi-Suan-Cha groups showed clear kidney structures with no obvious abnormalities. Compared with the normal control group, the model group showed increased URAT1/GLUT9 protein expression and decreased ABCG2/OAT1 protein expression. Compared with the model group, both Yi-Suan-Cha groups showed decreased URAT1/GLUT9 protein expression and increased ABCG2/OAT1 protein expression. Compared with that in the normal control group, URAT1/GLUT9 mRNA expression increased in the model group. Compared with the model group, the low-dose and high-dose Yi-Suan-Cha groups showed decreased URAT1/GLUT9 mRNA expression and increased ABCG2/OAT1 mRNA expression. CONCLUSION: Yi-Suan-Cha may lower uric acid level by downregulating URAT1/GLUT9 expression and upregulating ABCG2/OAT1 expression.

11.
J Integr Plant Biol ; 63(9): 1639-1648, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34170614

RESUMO

Rice blast and bacterial blight are important diseases of rice (Oryza sativa) caused by the fungus Magnaporthe oryzae and the bacterium Xanthomonas oryzae pv. oryzae (Xoo), respectively. Breeding rice varieties for broad-spectrum resistance is considered the most effective and sustainable approach to controlling both diseases. Although dominant resistance genes have been extensively used in rice breeding and production, generating disease-resistant varieties by altering susceptibility (S) genes that facilitate pathogen compatibility remains unexplored. Here, using CRISPR/Cas9 technology, we generated loss-of-function mutants of the S genes Pi21 and Bsr-d1 and showed that they had increased resistance to M. oryzae. We also generated a knockout mutant of the S gene Xa5 that showed increased resistance to Xoo. Remarkably, a triple mutant of all three S genes had significantly enhanced resistance to both M. oryzae and Xoo. Moreover, the triple mutant was comparable to the wild type in regard to key agronomic traits, including plant height, effective panicle number per plant, grain number per panicle, seed setting rate, and thousand-grain weight. These results demonstrate that the simultaneous editing of multiple S genes is a powerful strategy for generating new rice varieties with broad-spectrum resistance.

12.
Chin J Nat Med ; 19(6): 422-431, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34092293

RESUMO

Colon cancer-related anemia (CCRA) is mainly caused by systemic inflammation, intestinal bleeding, iron deficiency and chemotherapy-induced myelosuppression in colon cancer. However, the best therapeutic schedule and related mechanism on CCRA were still uncertain. Studies on blood enrichment and anti-tumor effects of combined Danggui Buxue Decoction (DBD), Fe and rhEPO based on CCRA and gut microbiota modulation were conducted in this paper. Here, CCRA model was successfully induced by subcutaneous inoculation of CT-26 and i.p. oxaliplatin, rhEPO + DBD high dosage + Fe (EDF) and rhEPO + DBD high dosage (ED) groups had the best blood enrichment effect. Attractively, EDF group also showed antitumor activity. The sequencing results of gut microbiota showed that compared to P group, the relative abundances of Lachnospiraceae and opportunistic pathogen (Odoribacter) in ED and EDF groups were decreased. Interestingly, EDF also decreased the relative abundances of cancer-related bacteria (Helicobacter, Lactococcus, Alloprevotella) and imbalance-inducing bacteria (Escherichia-Shigella and Parabacteroides) and increased the relative abundances of butyrate-producing bacteria (Ruminococcaceae_UCG-014), however, ED showed the opposite effects to EDF, this might be the reason of the smaller tumor volume in EDF group. Our findings proposed the best treatment combination of DBD, rhEPO and Fe in CCRA and provided theoretical basis and literature reference for CCRA-induced intestinal flora disorder and the regulatory mechanism of EDF.


Assuntos
Anemia , Neoplasias do Colo , Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Anemia/tratamento farmacológico , Anemia/etiologia , Animais , Neoplasias do Colo/complicações , Neoplasias do Colo/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia
13.
Nat Commun ; 12(1): 3428, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103526

RESUMO

Dysregulated extravillous trophoblast invasion and proliferation are known to increase the risk of recurrent spontaneous abortion (RSA); however, the underlying mechanism remains unclear. Herein, in our retrospective observational case-control study we show that villous samples from RSA patients, compared to healthy controls, display reduced succinate dehydrogenase complex iron sulfur subunit (SDHB) DNA methylation, elevated SDHB expression, and reduced succinate levels, indicating that low succinate levels correlate with RSA. Moreover, we find high succinate levels in early pregnant women are correlated with successful embryo implantation. SDHB promoter methylation recruited MBD1 and excluded c-Fos, inactivating SDHB expression and causing intracellular succinate accumulation which mimicked hypoxia in extravillous trophoblasts cell lines JEG3 and HTR8 via the PHD2-VHL-HIF-1α pathway; however, low succinate levels reversed this effect and increased the risk of abortion in mouse model. This study reveals that abnormal metabolite levels inhibit extravillous trophoblast function and highlights an approach for RSA intervention.


Assuntos
Aborto Habitual/metabolismo , Vilosidades Coriônicas/metabolismo , Ácido Succínico/metabolismo , Aborto Habitual/enzimologia , Aborto Habitual/genética , Animais , Estudos de Casos e Controles , Hipóxia Celular , Linhagem Celular Tumoral , Ilhas de CpG/genética , Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação da Expressão Gênica , Glicólise , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metaboloma , Camundongos Endogâmicos C57BL , Gravidez , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-fos/metabolismo , Fatores de Risco , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética , Trofoblastos/metabolismo , Trofoblastos/patologia
14.
Environ Pollut ; 287: 117231, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34000672

RESUMO

The Yellow River is the second largest river in China. Carbon transport by the Yellow River has significant influence on riverine carbon cycles in Asia. During the wet season, the riverine carbon was mainly found in dissolved form, i.e., dissolved organic carbon (DOC), along the entire course of the river. The distinct spatial variations of DOC concentration were observed at different reaches of the mainstream (p < 0.01), while the highest mean DOC concentration was generally observed at midstream (4.13 ± 0.91 mg/L). Carbon stable isotope analysis δ13C and C: N ratio of DOC, evidenced the sources of DOC in headwater and upstream were primarily the terrestrial plants (94% and 61%), but it was changed to soil organic matter (SOM) in mid- and downstream (36% and 37%), and the contribution of sewage to DOC were also increased to 17% and 18%. In the whole mainstream of the Yellow River, water temperature (WT) had a significant impact on DOC concentration, and it could explain 67% of the DOC variance. However, in a large catchment, the driving mechanisms on the DOC variations in headwaters will not necessarily be those controlling DOC trends in downstream. The study firstly quantified, in headwater and upstream, the natural factors explained as much as 65% and 73% of the DOC variations, respectively. In mid- and downstream areas, DOC was significantly influenced by the amount of wastewater discharged by the industry and the use of chemical fertilizers (p < 0.05). These findings may facilitate a better assessment of global riverine carbon cycling and may help to reveal the importance of the balance between development and environmental sustainability with the changing DOC transport features in the Yellow River due to human disturbances.


Assuntos
Carbono , Monitoramento Ambiental , Carbono/análise , Isótopos de Carbono/análise , Humanos , Rios , Estações do Ano
15.
Sci Total Environ ; 789: 147867, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34052498

RESUMO

The projections of mean temperature, precipitation (P), and potential evapotranspiration (PET) reflect the probabilities of long-term changes of hydrologic processes and induced extreme events. In this paper, we investigated the future changes in some pivotal climatic variables (mean temperature, precipitation, and potential evapotranspiration) under 1.5 °C, 2.0 °C, and 3.0 °C specific warming levels (SWLs) across the Indus River Basin of South Asia. The seven global climate models output under seven different emission scenarios (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5) from the latest Sixth phase of Coupled Model Intercomparison Project (CMIP6) are used for this purpose. The Penman-Monteith approach is applied to estimate PET, and the water balance equation is for reflecting water surplus/deficit. Results indicate that except for precipitation, the greater increases in temperature and PET are inclined to happen with continued global warming. The highest increase in temperature is accounted for 14.6% (2.4 °C), and the enhanced PET is estimated at 5.2% higher than the reference period (1995-2014) under 3.0 °C SWL. While the precipitation is projected to increase by the highest 4.8% for 2.0 °C warming level. The differences in regional climate for an additional 0.5 °C (2.0-1.5 °C) and 1.0 °C (3.0-2.0 °C) of warming, the temperature is projected to increase by 0.4 °C and 0.9 °C in the entire IRB respectively. The highest increase in mean temperature (5.1%) and PET (2.4%) in the IRB are predicted to intensify for an additional 1.0 °C than that of 0.5 °C of warming, but precipitation is intended to decrease by 0.4%. Spatially, the increase in temperature, precipitation, and PET are dominated towards high elevation in the upper basin (north) under all the SWLs. The increased variability in climatological parameters across IRB depicts an evident occurrence of both wet events (upper basin) as well as dry events (lower basin) with the increase in global average temperature rise. However, these findings provide an insightful basis for water resource management as well as initiating mitigation and adaptation measures in the IRB related to water surplus (floods) and water deficit (droughts).


Assuntos
Mudança Climática , Rios , Ásia , Hidrologia , Temperatura
16.
Environ Res ; 199: 111299, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33984309

RESUMO

Water clarity, denoted by the Secchi disk depth (SDD), is one of the most important indicators for monitoring water quality. In the Songhua River basin (SHRB), few studies have used Landsat to monitor long-term (3-4 decades) changes in lake SDD and explore the impact of natural and human factors on SDD interannual variation at the watershed scale. Lakes in the SHRB are of great significance to local populations. Understanding the spatiotemporal dynamics of SDD could help policymakers manage, protect, and predict lake water quality. We utilized the Landsat red/blue band ratio in the Google Earth Engine to estimate the SDD of 77 lakes and generated annual mean SDD maps from 1990 to 2018. The results of the SDD interannual changes showed that the water quality in the SHRB has improved since 2005. Specifically, the SDD in the SHRB displayed a significant increasing trend (p < 0.05) from 0.29 m in 2005 to 0.37 m in 2018. Moreover, the number of lakes displaying a significant increasing trend for SDD increased from 18 between 1990 and 2005 to 31 between 2005 and 2018. We also found that use of chemical fertilizer significantly impacted lakes, followed by wastewater discharge and normalized difference vegetation index. Improvements in the quantity and ability of wastewater discharge treatment and increased vegetation cover have alleviated water pollution; however, the non-point pollution of agriculture still poses a threat to some lakes in the SHRB. Therefore, more efforts should be made to further improve the aquatic ecological environment of SHRBs.


Assuntos
Rios , Qualidade da Água , China , Monitoramento Ambiental , Humanos , Lagos , Água , Poluição da Água
17.
Front Immunol ; 12: 628358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025639

RESUMO

Irinotecan (CPT-11)-induced gastrointestinal toxicity strongly limits its anticancer efficacy. Glycyrrhiza uralensis Fisch., especially flavonoids, has strong anti-inflammatory and immunomodulatory activities. Herein, we investigate the protective effect of the total flavonoids of G. uralensis (TFGU) on CPT-11-induced colitis mice from the perspective of gut microbiota and fecal metabolism. The body weight and colon length of mice were measured. Our results showed that oral administration of TFGU significantly attenuated the loss of body weight and the shortening of colon length induced by CPT-11. The elevated disease activity index and histological score of colon as well as the up-regulated mRNA and protein levels of TNF-α, IL-1ß, and IL-6 in the colonic tissue of CPT-11-treated mice were significantly decreased by TFGU. Meanwhile, TFGU restored the perturbed gut microbial structure and function in CPT-11-treated mice to near normal level. TFGU also effectively reversed the CPT-11-induced fecal metabolic disorders in mice, mainly call backing the hypoxanthine and uric acid in purine metabolism. Spearman's correlation analysis further revealed that Lactobacillus abundance negatively correlated with fecal uric acid concentration, suggesting the pivotal role of gut microbiota in CPT-11-induced colitis. Since uric acid is a ligand of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, TFGU was further validated to inhibit the activation of NLRP3 inflammasome by CPT-11. Our findings suggest TFGU can correct the overall gut microbial dysbiosis and fecal metabolic disorders in the CPT-11-induced colitis mice, underscoring the potential of using dietary G. uralensis as a chemotherapeutic adjuvant.


Assuntos
Anti-Inflamatórios/farmacologia , Bactérias/efeitos dos fármacos , Colite/prevenção & controle , Colo/efeitos dos fármacos , Fezes/microbiologia , Flavonoides/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Glycyrrhiza uralensis , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Bactérias/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Disbiose , Flavonoides/isolamento & purificação , Glycyrrhiza uralensis/química , Inflamassomos/metabolismo , Mediadores da Inflamação/metabolismo , Irinotecano , Masculino , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Extratos Vegetais/isolamento & purificação
18.
J Thorac Dis ; 13(2): 1196-1204, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33717592

RESUMO

Background: Surgery remains the best option for treating early-stage non-small cell lung cancer (NSCLC), and lymph node dissection (LND) is an important step in this approach. However, the extent of LND in the general age population, especially in young patients, is controversial. This retrospective study aimed to investigate the correlation between systematic lymph node dissection (SLND) and prognosis in young (≤40 years) patients with stage IA NSCLC. Methods: Clinicopathological data of 191 patients aged ≤40 years who underwent surgical pulmonary resection for stage IA NSCLC between January 2010 and December 2016 were retrospectively collected. Of the patients, 104 received SLND (SLND group), while the other 87 patients underwent sampling or no LND (non-SLND group). The disease-free survival (DFS) and overall survival (OS) curves of the patients from each group were plotted using the Kaplan-Meier method, and the correlations of the patients' clinical factors with prognosis were also analyzed. Results: The median follow-up period was 55 months. During follow-up, 7 patients died, and recurrence or metastasis was detected in 16 patients. Kaplan-Meier analysis revealed no difference in DFS (P=0.132) between the SLND and non-SLND group, but a significant difference was found between the groups in OS (P=0.022). Additionally, there was no statistically pronounced difference in OS or DFS between male and female patients. Multivariate survival analysis showed that the type of SLND, as well as tumor size, is an independent prognostic factor for DFS (HR, 3.530; 95% CI, 1.120-11.119; P=0.031) and OS (HR, 13.076; 95% CI, 1.209-141.443; P=0.034). Conclusions: For young (age ≤40) stage IA NSCLC patients with pathological invasive adenocarcinoma, intraoperative SLND can improve the DFS and OS. Further studies are needed to verify the most optimal degree of LND in young patients.

19.
Sci Total Environ ; 771: 145186, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736148

RESUMO

Drought has a substantial socioeconomic impact under the changing climate. The estimation of population exposure to drought could be the pivotal signal to predict future water scarcity in the climate hotspot of South Asia. This study examines the changing population exposure to drought across South Asia using 20 climate model ensembles from the latest CMIP6 and demographic data under shared socioeconomic pathways (SSPs). Underpinning the latest version of the IPCC 6th Assessment Report (AR6), this paper focuses on the 2021-2040 (near-term), 2041-2060 (mid-term), and 2081-2100 (long-term) periods to project population exposure changes relative to the reference period (1995-2014) under four SSP-RCP scenarios. Drought events are detected by adopting the standardized precipitation evapotranspiration index (SPEI) and run theory method. Model validation suggests that CMIP6-GCM performs well in projecting climate variables and capturing drought events. The results show that the projected increases in frequent drought events and affected areal coverage are stronger during the early part of the century and weaker at the end under all scenario combinations. In relative terms, the projected increase in the number of people exposed to drought is dominant (>1.5-fold) in the near-term and mid-term periods but decreases in the long-term period. Compared to the reference period, the leading increase in population exposure (2.3-fold) is projected under the newly designed gap scenario (SSP3-7.0) in the mid-term period. A surprising decline in the number of exposed populations was estimated to be 18.8% under SSP5-8.5 by the end of the century. The mitigating effect of the predicted heavy precipitation will decrease droughts in the late future. Spatially, increasing exposure will become more pronounced across India and Afghanistan. Furthermore, the population change effect is mainly responsible for the exposure changes in South Asia. However, this study strongly recommends future 'plausible world' regional rivalry pathways (SSP3) scenario-combinations into consideration for policymaking in regard to water management as well as migration planning over South Asia.

20.
Sci Total Environ ; 778: 146271, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33721636

RESUMO

Lake eutrophication has attracted the attention of the government and general public. Chlorophyll-a (Chl-a) is a key indicator of algal biomass and eutrophication. Many efforts have been devoted to establishing accurate algorithms for estimating Chl-a concentrations. In this study, a total of 273 samples were collected from 45 typical lakes across China during 2017-2019. Here, we proposed applicable machine learning algorithms (i.e., linear regression model (LR), support vector machine model (SVM) and Catboost model (CB)), which integrate a broad scale dataset of lake biogeochemical characteristics using Multispectral Imager (MSI) product to seamlessly retrieve the Chl-a concentration. A K-means clustering approach was used to cluster the 273 normalized water leaving reflectance spectra [Rrs (λ)] extracted from MSI imagery with Case 2 Regional Coast Colour (CR2CC) processor into three groups. The pH, electrical conductivity (EC), total suspended matter (TSM) and dissolved organic carbon (DOC) from three clustering groups had significant differences (p < 0.05**), indicating that water quality parameters have an integrated impact on Rrs(λ)-spectra. The results of machine learning algorithms integrating demonstrated that SVM obtained a better degree of measured- and derived- fitting (calibration: slope = 0.81, R2 = 0.91; validation: slope = 1.21, R2 = 0.88). On the contrary, the documented nine Chl-a algorithms gave poor results (fitting 1:1 linear slope < 0.4 and R2 < 0.70) with synchronous train and test datasets. It demonstrated that machine learning provides a robust model for quantifying Chl-a concentration. Further, considering three Rrs(λ) clustering groups by k-means, Chl-a SVM model indicated that cluster 1 group gave a better retrieving performance (slope = 0.71, R2 = 0.78), followed by cluster 3 group (slope = 0.77, R2 = 0.64) and cluster 2 group (slope = 0.67, R2 = 0.50). These are related to the low TSM and high DOC levels for cluster-1 and cluster-3 Rrs(λ) spectra, which reduce the influence of particle in red bands for Rrs(λ) signal. Our results highlighted the quantification of lake Chl-a concentrations using MSI imagery and SVM, which can realize the large-scale monitoring and more appropriate for medium/low Chl-a level. The remote estimation of Chl-a based on artificial intelligence can provide an effective and robust way to monitor the lake eutrophication on a macro-scale; and offer a better approach to elucidate the response of lake ecosystems to global change.


Assuntos
Inteligência Artificial , Lagos , Algoritmos , China , Clorofila/análise , Clorofila A/análise , Ecossistema , Monitoramento Ambiental , Eutrofização
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...