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1.
Environ Pollut ; 341: 122899, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37967714

RESUMO

With the development of the economy, the problem of urban black odorous water bodies has become increasingly significant, having a serious impact on the environment. As important means of remediating aquatic environments, pollution source control and water replenishment are of great significance in improving water quality. This study takes the Qianshan River Basin in Zhuhai City as its study area to simulate their effects on the improvement of water quality. A coupled model of water quantity and quality in Qianshan River Basin was constructed using MIKE11to analyze the water quality compliance rate, with sewage interception rates of 85%, 90%, and 95%, and to investigate the effect of pollution source control on the improvement of the aquatic environment. Using different sewage interception rates, the amount of water replenishment was calculated in order to meet water quality standards, the water replenishment scheme was determined via river-specific and time-specific methods, and the model was used to analyze the replenishment effect of the scheme. The results show that increasing the sewage interception rate can significantly improve the COD compliance rate, and improve the NH3-N and TP compliance rate; however, the enhancement effect is not sufficiently significant. When a sewage interception rate of 95% is implemented, there are still five rivers with a low NH3-N compliance rate, and six rivers with low a TP compliance rate. Comparing the water replenishment effect under different sewage interception rates of 85% and 95%, the water replenishment program alongside a sewage interception rate of 95% can effectively improve the aquatic environment and the water quality essentially meets the standard under different rainfall conditions; this demonstrates that the program presented herein can be used as the aquatic environment remediation program of choice for the Qianshan River Basin.


Assuntos
Recuperação e Remediação Ambiental , Poluentes Químicos da Água , Qualidade da Água , Rios , Monitoramento Ambiental/métodos , Esgotos , China , Poluentes Químicos da Água/análise , Poluição da Água/análise
2.
Opt Lett ; 48(22): 5859-5862, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966737

RESUMO

Photonic digital-to-analog converters (PDACs) with segmented design can achieve better performance than conventional binary PDACs in terms of effective number of bits (ENOB) and spurious-free dynamic range (SFDR). However, segmented PDACs generally require an increased amount of laser sources. Here, a structure of bipolar segmented PDAC based on laser wavelength multiplexing and balanced detection is proposed. The number of lasers is reduced by a half compared to a conventional segmented design with the same nominal resolution. Moreover, ideal bipolar output with no direct-current bias can be achieved with balanced detection. A proof-of-concept setup with a sampling rate of 10 GSa/s is constructed by employing only four lasers. The PDAC consists of four unary weighted channels and four ternary weighted channels. The measured ENOB and SFDR are 4.6 bits and 37.0 dBc, respectively. Generation of high-quality linear frequency-modulated radar waveforms with an instantaneous bandwidth of 4 GHz is also demonstrated.

3.
Angew Chem Int Ed Engl ; 62(19): e202301479, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36896823

RESUMO

The carbon to CaC2 route is promising to provide a sustainable elementary unit, C2 H2 , for the organic synthesis industry, but the traditional thermal reaction process suffers from low carbon efficiency, harmful gas contamination, high temperature operation, and risky CO management. We herein report a high carbon efficiency (ca. 100 %) conversion of biochar to C2 H2 through an electrolytic synthesis of solid CaC2 in molten CaCl2 /KCl/CaO at 973 K. The main reactions are carbon reduction to CaC2 at the solid carbon cathode and oxygen evolution at an inert anode. Meanwhile, the electrolysis removes S and P from the solid cathode, avoiding the formation of CaS and Ca3 P2 in CaC2 and consequently eliminating H2 S and PH3 contamination in the finally produced C2 H2 .

4.
Artigo em Inglês | MEDLINE | ID: mdl-36613194

RESUMO

Layered double hydroxide (LDH)-doped chicken-manure biochar (CMB) with long-term stability was synthesized to immobilize Pb/Cd. MgAl-Cl-LDH-doped CMB (MHs) showed prominent long-term oxidation resistance and the least biodegradation sensitivity. Efficient Pb/Cd adsorption was observed on MHs, and the maximum adsorption capacities of Pb(II)/Cd(II) reached 1.95 mmol/g and 0.65 mmol/g, respectively. Precipitation and isomorphous substitution were identified as the key adsorption mechanisms, which formed highly stable Pb/Cd species (PbAl-CO3-LDH, Pb3(OH)2CO3, CdAl-Cl-LDH and CdCO3). Pb(II) and Cd(II) precipitated with CO32- in MHs; meanwhile, Mg(II) and Ca(II) in LDH layers were substituted by Pb(II) and Cd(II) respectively. Therefore, MHs had the potential for long-term stability of Pb/Cd. Moreover, complexation and electrostatic adsorption also contributed to the Pb/Cd immobilization to a certain extent. When 5% MHs (w/w) was applied to Pb/Cd contaminated smelting site soils, the soil pH increased from 5.9 to 7.3. After applying MHs for 25 d, the content of bioavailable Pb(II) and Cd(II) decreased by 98.8% and 85.2%, respectively, and the content of soluble Pb and Cd dropped by 99.5% and 96.7%. This study paves the way for designing a novel LDH doped CMB as efficient Pb/Cd immobilizers for smelting site soils.


Assuntos
Cádmio , Poluentes do Solo , Animais , Cádmio/química , Esterco , Galinhas , Chumbo , Hidróxidos , Carvão Vegetal/química , Solo/química , Poluentes do Solo/química
5.
Appl Biochem Biotechnol ; 195(3): 1644-1655, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36355336

RESUMO

Cisplatin broadly functions as a routine treatment for lung adenocarcinoma (LUAD) patients. However, primary and acquired cisplatin resistances frequently occur in the treatment of LUAD patients, seriously affecting the therapeutic effect of cisplatin in patients. We intended to illustrate the impact of let-7c-5p/cell division cycle 25A (CDC25A) axis on cisplatin resistance in LUAD. Expression of let-7c-5p and CDC25A was analyzed via quantitative real-time polymerase chain reaction. The interaction between the two was verified by dual-luciferase reporter detection. For detecting half-maximal inhibitory concentration value of cisplatin in LUAD cells and cell proliferation, we separately applied Cell Counting Kit-8 and colony formation assays. Furthermore, we measured cell apoptosis and cell cycle distribution via flow cytometry, as well as cell cycle-related protein expression via Western blot. Let-7c-5p was evidently downregulated in LUAD, while CDC25A was remarkably upregulated. Let-7c-5p upregulation arrested LUAD cells to proliferate, stimulated cell apoptosis, and arrested cell cycle in G0/G1 phase, thus enhancing sensitivity of LUAD cells to cisplatin. In terms of mechanism, CDC25A was directly targeted by let-7c-5p, and the influence of let-7c-5p overexpression on LUAD proliferation, apoptosis, cell cycle, and cisplatin resistance could be reversed by CDC25A upregulation. Let-7c-5p improved sensitivity of LUAD cells to cisplatin by modulating CDC25A, and let-7c-5p/CDC25A axis was an underlying target for the intervention of LUAD cisplatin resistance.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Humanos , Cisplatino/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Proliferação de Células , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismo , Fosfatases cdc25/farmacologia
6.
J Hazard Mater ; 445: 130519, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36493648

RESUMO

Trivalent chromium is generally assumed to form insoluble species, resulting in low mobility of Cr(III) in soils. Here, we report continuous distributions (0-19 m) of a high concentration of Cr(III) in the alkaline soils of a historically industrial site for producing Na2Cr2O7, CrO3, and Cr2O3, which challenges this abovementioned conventional wisdom. The thermodynamic equilibrium model showed the low possibility of Cr(III) originating from Cr(VI) reduction under the redox conditions of this study. The AF4-MALLS-ICP-MS and µ-XRF-XANES were used to identify the particle size distribution of Cr(III)-containing colloids and Cr(III) species in mobile colloids. In any soil layer, Cr(III) accounts for 71.1-94.3% of the total Cr in submicron soil colloids and is composed of submicron intrinsic Cr2O3 (55.2%-63.8%), Cr(OH)3 (0-33.0%), and Cr(III) adsorbed by ferrihydrite (0-19.0%) and clay montmorillonite (11.1%-21.1%) colloid. On the contrary, Cr(VI) was mainly distributed in bulk soil (> 2 µm) except for the topsoil, accounting for 62.6-90.0% of total Cr(VI). Organic matter content and soil texture are the most critical factors driving the mobilization of submicron colloids in soils by principal component analysis. Humic acid (HA) formed HA-corona on Cr2O3 surface and enhanced colloidal dispersion, thereby accelerating the long-distance mobilization of submicron Cr2O3 colloids in alkaline soil layers, whereas the heteroaggregation of clay colloid with Cr2O3 was only favorable for short-distance mobilization. Our findings help to re-recognize the potential migration risks of insoluble heavy metals in soils.


Assuntos
Poluentes do Solo , Solo , Argila , Cromo/análise , Substâncias Húmicas/análise , Oxirredução , Poluentes do Solo/análise , Coloides
7.
Water Res ; 221: 118799, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35780765

RESUMO

Iron in the form of (oxyhydr)oxides plays a profound role in the (im)mobilization of heavy metals in environmental geochemical processes occurring in the soil-groundwater system. Here, the influence of saltwater intrusion on Fe-(oxyhydr)oxide-mediated (im)mobilization of Ni(II) and Zn(II) in redox-fluctuating shallow aquifers was evaluated by chemical extraction, µ-XRF-XANES analysis, and 16S rRNA high-throughput sequencing. In phreatic water, the ferrihydrite-bound Ni/Zn (Fh-Ni/Zn) in soils contributed to a 12%-17% increase in carbonate-bound Ni/Zn (Cb-Ni/Zn) due to its own reductive dissolution, whereas the illite-adsorbed Ni/Zn (illite-Ni/Zn) only contributed 6%, 7%. The relative abundance of non-salt tolerant anaerobic Herbaspirillum and iron-reducing associated Ralstonia in soils accounted for nearly 50%. During the oxidation stage, the dissolved ferrihydrite reprecipitated to bind free Ni/Zn. However, saltwater invasion strongly weakened the dissolution-precipitation of ferrihydrite by inhibiting the growth of non-salt tolerant anaerobes and iron-reducing bacteria, and highlighted the contribution of illite-Ni/Zn. Under brackish water intrusion, illite-Zn contributed to a 12% increase in Cb-Zn, thereby surpassing the contribution of Fh-Zn (8%). Under seawater invasion, the dissolution-precipitation of ferrihydrite hardly occurred and the anaerobic salt-tolerant Bacillus (> 95%) prevailed. Therefore, the increase of Cb-Ni/Zn (7%-15%) in the reduction stages was contributed by illite-Ni/Zn. However, in the oxidation stages, the carbonate replaced the original role of reprecipitated ferrihydrite to bind the free Ni/Zn in solutions. These newly recognized mechanisms may be the key to predicting the mobility of toxic elements and developing appropriate remediation techniques of permeable reactive barriers under salinity stress.


Assuntos
Água Subterrânea , Solo , Ferro/análise , Oxirredução , Óxidos , RNA Ribossômico 16S , Zinco/análise
8.
Iran J Basic Med Sci ; 25(2): 193-197, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35655597

RESUMO

Objectives: Renal tubular damage is critical pathological feathers of diabetic nephropathy (DN). This study aimed to explore the protective activity and related mechanisms of crocin in renal epithelial cell injury induced by high glucose. Materials and Methods: Renal tubular epithelial HK-2 cells were cultured with D-glucose to establish an in vitro DN model. Cell viability was evaluated by CCK-8 assay. Apoptosis was detected by Annexin V-FITC kit. Oxidative stress was evaluated by colorimetry. RT-qPCR was carried out to determine the mRNA expressions of NF-E2-related factor 2 (Nrf2) and its pathway genes. Western blot was applied to determine the protein expressions of Nrf2 and related proteins. Results: High glucose (5.5, 30, and 50 mM D-glucose) decreased cell viability at 72 hr, which was attenuated by crocin (25 and 50 µM). Crocin also attenuated the high glucose (30 mM D-glucose) induced apoptosis of HK-2 cells, decreased MDA content, and increased SOD activity in culture media. Crocin increased mRNA levels of Nrf2, HO-1, and NQO1. Moreover, crocin increased protein expressions of Nrf2, Sirtuin 1 (SIRT1), and p-Akt (Ser473). Inhibition of Nrf2 using siRNA, and inhibitors of SIRT1 (nicotinamide, NAM, 20 µM) and PI3K/Akt (LY294002, 50 µM) all attenuated the protective effect of crocin. Nrf2 siRNA and NAM also partially attenuated the inhibitory effect on oxidative stress and increase in the Nrf2 protein by crocin treatment. Conclusion: Crocin protects renal epithelial cells against injury induced by high glucose, and the mechanism is associated with partial activation of the SIRT1-Nrf2 pathway.

9.
Am J Transl Res ; 14(3): 1901-1908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422950

RESUMO

OBJECTIVE: To explore the therapeutic efficacy of the levonorgestrel-releasing intrauterine system combined with turtle shell decocted pills for endometriosis and their effect on cellular immune function. METHODS: Clinical data of 118 patients with endometriosis admitted to Taizhou First People's Hospital from January 2019 to January 2020 were retrospectively analyzed. The patients were assigned into a single-drug group (n=68) and a combined traditional Chinese medicine group (n=50) according to treatment methods. The single-drug group was treated with the levonorgestrel-releasing intrauterine system, and the combined traditional Chinese medicine group was treated with additional turtle shell decocted pills for three cycles for a total of 12 weeks. Enzyme-linked immunosorbent assay was adopted to measure the concentration of Th1 cytokines (tumor necrosis factor (TNF)-α and interferon (IFN)-γ) and Th2 cytokines (interleukin (IL)-6 and IL-10), and the protein level of programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1). The levels of serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and estradiol (E2) were compared between the two groups. The response rate of treatment, the control rate of blood pressure and the incidence of adverse reactions were recorded in both groups. RESULTS: The response rate of treatment in the combined traditional Chinese medicine group was higher than that in the single-drug group (P<0.05). Compared to before treatment, the TNF-α and IFN-γ increased in both groups after treatment, and the expressions were higher in the combined traditional Chinese medicine group than in the single-drug group (all P<0.05). After treatment, the levels of IL-6, IL-10, PD-1, and PD-L1 decreased, and the decreases in the combined traditional Chinese medicine group were greater than those in the single-drug group (all P<0.05). Serum LH, FSH and E2 levels before and after the treatment in the two groups were not statistically different (all P>0.05). The incidence of treatment-related adverse reactions between the two groups of patients was also not statistically different (P>0.05). CONCLUSION: Turtle shell decocted pills can increase the clinical efficacy of levonorgestrel-releasing intrauterine system in the treatment of endometriosis, reduce levels of PD-1, and PD-L1 and improve cellular immune function. The pills do not affect the secretion of ovarian hormones or increase adverse reactions.

10.
Chemosphere ; 293: 133583, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35026201

RESUMO

The emerging animal-derived biochar (AB) has shown potential for mitigating the contamination of cationic heavy metals, but has no affinity to oxyanionic metals. In this study, we developed an AB/ferrihydrite composite with a AB/Fe mass ratio of 4.0 (ABF-4) for the simultaneous adsorption of cationic Pb(II)/Cd(II) and anionic As(III). ABF-4 is a type of hydroxyapatite-rich biochar coated with nanoscale iron hydroxide aggregates. The adsorption of Pb(II), Cd(II), and As(III) on ABF-4 were 2.64, 1.55, and 0.48 mmol/g, and were 135%, 150%, and 4500% higher than those of pure AB, respectively. The enhanced adsorption of Pb(II) and Cd(II) by ABF-4 is partially due to the increase in surface area and micropores. The nano-sized ferrihydrite on ABF might help form surface complexation with As(III) and oxidize As(III) to As(V). In multimetal systems, Pb(II) and Cd(II) can promote As(III) adsorption due to the formation of NaPb4(AsO4)3 precipitate and the ternary complex of arsenite and cadmium with ABF-4, whereas Cd(II) adsorption might be inhibited because of the surface coverage of Pb5(PO4)3Cl precipitate on ABF-4. However, the coexistence of Pb in soils does not influence the immobilization of Cd. The amendment of ABF-4 can considerably decrease the availability of Pb, Cd, and As in soils from Pb-Zn smelting sites. Hence, ABF-4 is a promising multifunctional material for the potential immobilization of multicomponent heavy metals.


Assuntos
Cádmio , Poluentes do Solo , Adsorção , Animais , Carvão Vegetal , Compostos Férricos , Chumbo , Solo , Poluentes do Solo/análise
11.
J Hazard Mater ; 424(Pt C): 127584, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736214

RESUMO

In this work, the mechanism of Pb(II)-mediated precipitation transformation to improve the removal of Cr(VI)-oxyanion on biogenic hydroxyapatite (BHAp) were investigated. The Pb(II)-preloading formed pyromorphite [Pb5(PO4)3Cl] precipitate on the BHAp surface (Pb@BHAp), thus causing an increase of 2.2 times in the uptake of Cr(VI) by Pb@BHAp at pH of 2.4. It was primarily due to the dissolution of Pb5(PO4)3Cl accompanied with the release of Pb(II), resulting in the rapid formation of crocoite (PbCrO4). Although the Ksp of Pb5(PO4)3Cl was approximately 23 orders of magnitude lower than that of PbCrO4, Pb(II)-mediated precipitation transformation could still occur. XRD and SEM-EDX analyses demonstrated that the process was a time-dependent that included rapid crystal precipitation in the initial 10 min and subsequent precipitate accumulation for several hours. The Pb(II) released from the dissolution of Pb5(PO4)3Cl was immediately immobilized by Cr(VI); therefore, it did not cause any retention risk of Pb(II) in the solution. Furthermore, a small quantity of Cr(VI) could be reduced to Cr(III) by BHAp, and Cr(III) could enter into the BHAp lattice for the exchange of Ca(II). This study provides a new insight into the resource utilization of Pb-bearing BHAp and a potential method for the successive removal of Pb(II) and Cr(VI).


Assuntos
Durapatita , Chumbo , Cromo
12.
Diabetes Metab Syndr Obes ; 14: 3461-3470, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34366677

RESUMO

OBJECTIVES: Bone may play a role in the modulation of insulin sensitivity. Insulin resistance can be caused by increased resistin. However, whether osteoclasts affect the insulin resistance via resistin remains unclear. In the present study, we show the expression of resistin in osteoclasts and the possible underlying role of resistin on glucose uptake-related insulin resistance in vitro. METHODS: Conditioned mediums (CM) were collected from Raw264.7 cells treated without (CCM) or with RANKL (CM3, treated with RANKL for 3 days; CM5, treated with RANKL for 5 days) and transfected with control or resistin siRNA (CMsiRNA). The osteoclast formation was examined by tartrate resistant acid phosphatase (TRAP) staining. C2C12 myoblasts were cultured with the CM or CMsiRNA. Glucose uptake was evaluated by 2-NBDG fluorescence intensity. Resistin expression was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay. Statistical analysis was performed by an independent two sample t-test or one-way ANOVA. RESULTS: The 2-NBDG fluorescence intensity was higher in C2C12 cells treated with CCM compared to those that received CM3 and CM5 (p < 0.05). Resistin mRNA and protein expressions were both increased in RAW264.7 cells treated with RANKL for 3 days and 5 days compared with those cells without RANKL administration. The 2-NBDG fluorescence intensities in C2C12 cells treated with CMsiRNA and CM5+Anti-resistin antibody were significantly higher than those cultured with CM5 (p < 0.05). CONCLUSION: Osteoclasts may promote glucose uptake-related insulin resistance by secreting resistin.

13.
Int J Endocrinol ; 2021: 5566019, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34007273

RESUMO

OBJECTIVES: Melatonin is an essential neuroendocrine hormone that participates in the regulation of sleep rhythm and cognitive function. This study aimed to determine serum melatonin levels with mild cognitive impairment (MCI) in patients with type 2 diabetes (T2DM). METHODS: A total of 247 T2DM patients were recruited in this retrospective study and divided into 75 subjects with MCI and 172 with normal cognition. Cognitive function was evaluated by the Montreal Cognitive Assessment (MoCA). Their blood sample was examined for the level of melatonin and other biochemical parameters. RESULTS: Melatonin concentration was decreased in MCI patients to non-MCI patients (P < 0.001). Melatonin level was negatively correlated with age (r = -0.202; P = 0.001), diabetes duration (r = -0.282; P < 0.001), serum HbA1c (r = -0.195; P = 0.002), hs-CRP (r = -0.324; P < 0.001), and TSH (r = -0.184; P = 0.004) levels and positively correlated with MoCA score, serum HDL-C (r = 0.145; P < 0.001), FT3 (r = 0.241; P < 0.001), and FT4 (r = 0.169; P = 0.008) levels. The multivariable analysis indicated that fewer years of formal education, longer diabetes duration, higher serum HbA1c, higher serum hs-CRP, and lower serum melatonin are the predisposing factors for MCI. CONCLUSION: Lower melatonin level was associated with cognitive impairment in patients with T2DM. Melatonin might serve as a potential protective molecule against cognitive dysfunction in T2DM.

14.
Int J Clin Pract ; 75(7): e14198, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33792117

RESUMO

BACKGROUND: The use of horse-riding simulators in the treatment of chronic low back pain has drawn considerable attention for its efficacy and acceptability to reduce chronic low back pain; because of the similarities in movements provided by equine-assisted therapies and the possible accessibility advantages. However, the results are conflicting. This study aimed to perform a meta-analysis of randomised controlled trials to assess the impact of treatments based on horse-riding simulators on chronic low back pain. METHODS: A systematic literature search up to January 2021 was performed and 11 studies were detected with 543 subjects with chronic low back pain at the baseline of the study, 257 of them were using horse-riding simulators, and 255 of them were inactive control group who continued their usual care, and similar kind of physical therapy (control). They reported a comparison between horse-riding simulators and control to reduce chronic low back pain. Mean differences (MD) with 95% confidence intervals (CIs) were calculated assessing the impact of treatments based on horse-riding simulators on chronic low back pain using the continuous method with a random or fixed-effect model. RESULTS: Significantly higher change-from-baseline pain outcomes was observed in Visual Analogue Scale (MD, -4.36; 95% CI, -6.24 to -2.30, P < .001), and Roland Morris Disability Questionnaire change-from-baseline (MD, -2.32; 95% CI, -3.52 to -1.12, P < .001) with horse-riding simulators compared with control. CONCLUSIONS: Using horse-riding simulators may lower the risk of chronic low back pain. This relationship forces us to recommend the use of horse-riding simulators to avoid any complications that could occur with chronic low back pain.


Assuntos
Dor Crônica , Terapia Assistida por Cavalos , Dor Lombar , Animais , Dor Crônica/terapia , Cavalos , Humanos , Dor Lombar/terapia , Medição da Dor , Modalidades de Fisioterapia , Escala Visual Analógica
15.
Chemosphere ; 276: 130089, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33743417

RESUMO

Prometryn is a herbicide that is widely used and frequently detected in aqueous environment and soil. Prometryn is chemically stable, biologically toxic, and easily to accumulate in living bodies, which can cause accumulate in the environment and acute and chronic toxicity to living creatures. In this study, factors affecting the degradation kinetics of prometryn chlorination were studied, including solution pH, bromide and ammonium concentrations, and temperature. Prometryn reacted quickly with aqueous chlorine following the pseudo-first-order kinetics. The maximum pseudo-first-order rate constant (kapp) appeared at pH 5 with the observed rate constant (kobs) as 190. 08 h-1; the minimum value of kapp reached at pH 9 with kobs as 5.26 h-1. The presence of Br- and increase of temperature both accelerated the degradation rate of prometryn during chlorination. The activation energy was calculated as 31.80 kJ/mol. Meanwhile 6 disinfection by-products (DBPs) were detected, namely: chloroform (CF), trichloroacetonitrile (TCAN), dichloroacetonitrile (DCAN), dichloroacetone, trichloronitromethane (TCNM), and trichloroacetone. Solution pH significantly affected the formation and distribution of DBPs. CF was the most formed carbonated DBP (C-DBP) with the maximum of 217.9 µg/L at pH 8, and its formation was significantly higher in alkaline conditions. For nitrogenated DBPs (N-DBPs), the yields of DCAN and TCAN were significantly higher in acidic conditions, while the maximum of TCNM achieved in neutral conditions. Because the toxicity of N-DBPs is higher than that of C-DBPs, the pH should be controlled in neutral or slight alkaline conditions during prometryn chlorination to effectively control DBP formation and reduce the related toxicity.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Desinfecção , Halogenação , Cinética , Prometrina , Poluentes Químicos da Água/análise
17.
Endocrine ; 67(3): 685-698, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31721088

RESUMO

PURPOSE: To comprehensively investigate the associations of subclinical thyroid dysfunction with BMD and fractures at various sites. METHODS: Comprehensive electronic and manual searches of databases were systematically conducted to identify prospective cohort studies from the inception of the databases to May 2019. The summary results for fractures and BMDs at various sites were calculated by relative risks (RRs) and weighted mean differences (WMDs) with corresponding 95% confidence intervals (CIs) using the random-effects model. RESULTS: Seventeen prospective cohorts from 24 studies were identified and 313,557 individuals were recruited in a final analysis. The summary RR indicated that subclinical hyperthyroidism was associated with an increased risk of any fracture (RR, 1.17; 95% CI, 1.08-1.26; P < 0.001), hip fracture (RR, 1.27; 95% CI, 1.09-1.48; P = 0.003), spine fracture (RR, 1.97; 95% CI, 1.31-2.97; P = 0.001), and non-spine fracture (RR, 1.19; 95% CI, 1.04-1.37; P = 0.014). However, there were no significant associations of subclinical hypothyroidism with the risk of any fractures (P = 0.166), hip fracture (P = 0.068), spine fracture (P = 0.818), and non-spine fracture (P = 0.277). Finally, subclinical hyperthyroidism was associated with lower distal forearm BMD in women, and ultradistal forearm BMD in both men and women, whereas subclinical hypothyroidism was associated with higher femur neck BMD in women. CONCLUSION: Subclinical hyperthyroidism could induce additional risk on fractures at any, hip, spine, and non-spine, whereas subclinical hypothyroidism did not have any impact on fractures. Moreover, BMD at the lower distal and ultradistal forearms might be affected by subclinical hyperthyroidism, and higher femur neck BMD could be affected by subclinical hypothyroidism.


Assuntos
Fraturas do Quadril , Hipertireoidismo , Doenças da Glândula Tireoide , Densidade Óssea , Feminino , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Humanos , Hipertireoidismo/complicações , Hipertireoidismo/epidemiologia , Masculino , Estudos Prospectivos
18.
Med Sci Monit ; 25: 5280-5288, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31309931

RESUMO

BACKGROUND Diabetic nephropathy (DN) is a disease characterized by oxidative stress and apoptosis of renal tubular epithelial cells driven by hyperglycemia. Apigenin is a flavonoid compound that possesses potent anti­apoptotic properties. The present study aimed to explore the protective effects and underlying mechanisms of apigenin on renal tubular epithelial cells exposed to hyperglycemia. MATERIAL AND METHODS Human renal epithelial cell HK-2 were incubated to D-glucose to establish in vitro DN model. The cell viability, lactate dehydrogenase (LDH) release, apoptosis and oxidative stress were evaluated. qRT-PCR was performed to determine the mRNA levels of NF-E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Western blot analysis was performed to measure the protein expressions of Nrf2. RESULTS In HK-2 cells, high glucose reduced cell viability in a concentration- and time-dependent manner. Apigenin suppressed the decrease in cell viability and increase in supernatant LDH release at 100 and 200 µM after 48-h treatment. Apigenin reduced apoptotic rate and pro-inflammatory cytokines production. Apigenin suppressed oxidative stress and increased mRNA expressions of Nrf2 and HO-1. Inhibition of Nrf2 using small interfering RNA (siRNA), or cotreatment with LY294002, an inhibitor of PI3K/Akt, abolished the protective effect on high glucose-induced injury, oxidative stress, and pro-inflammatory cytokines production by apigenin. LY294002 also attenuated the increase in Nrf2 protein by apigenin in high glucose-treated HK-2 cells. CONCLUSIONS Apigenin protects renal tubular epithelial cells against high glucose-induced injury through suppression of oxidative stress and inflammation via activation of the Nrf2 pathway.


Assuntos
Apigenina/farmacologia , Hiperglicemia/metabolismo , Túbulos Renais/efeitos dos fármacos , Antioxidantes/farmacologia , Apigenina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Flavonoides/farmacologia , Glucose/metabolismo , Heme Oxigenase-1/metabolismo , Hiperglicemia/tratamento farmacológico , Túbulos Renais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Substâncias Protetoras/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Huan Jing Ke Xue ; 40(4): 1797-1802, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087921

RESUMO

Colloid media are not only an important "sink" for pollutants in the aquatic environment, but also a crucial regulating unit for the biogeochemical cycle of pollutants. In this study, the distribution and environmental risk levels of ten typical pharmaceutically active compounds (PhACs) in the water phase of effluent-receiving rivers were investigated using cross-flow ultrafiltration, solid-phase extraction, and liquid chromatography-tandem mass spectrometry as the pretreatment and analysis methods. The results showed that the total concentrations of the ten PhACs in the dissolved phase and colloidal phase ranged from 27.2 to 168.1 ng·L-1 and 164.5 to 751.1 ng·g-1, respectively. Ibuprofen (IPF), roxithromycin (ROX), and erythromycin (ETM) are the dominating pollutants in the dissolved phase and colloidal phase, accounting for more than 80% of the total concentration. Strong adsorption properties for ROX, ketoconazole, ETM, and sertraline were found in the colloid phase, their colloid/water distribution coefficients (lgKcol) ranged from 3.2 to 4.0, and the percentage of PhACs absorbed to the colloidal phase reached 21.1%-34.5%. The risk assessment of acute and chronic toxicity to algae, daphnia, and fish showed that only IPF presented a high chronic risk to fish, while the risk levels of the other PhACs were at or below medium risk. It is worth noting that, in comparison with their acute risk, most PhACs have chronic negative effects on higher aquatic organisms.


Assuntos
Monitoramento Ambiental , Preparações Farmacêuticas/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , Ecotoxicologia , Esgotos , Águas Residuárias
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