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1.
Waste Manag ; 172: 43-50, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37708811

ABSTRACT

The safe disposal of waste cathode ray tubes (CRTs) has always been a serious problem due to the stable microstructure of toxic lead (Pb) located in glass. Thousands of researches have been trying to explore environmental and efficient ways to dispose of waste CRTs. To recycle lead from waste CRT funnel glass effectively, a mechanochemical reduction method has been developed in this research. Aluminum was used as a reductant, and the hydrochloric acid solution was used in the leaching process to separate lead from the solution. After mechanochemical ball milling with aluminum, lead ion in CRT funnel glass was transferred into nano-sized element lead. Lead recovery from CRT funnel glass increased significantly as compared to non-activated leaded glass. Approximately 40 % of lead was leached after mechanical activation without aluminum, while over 96 % of lead in the CRT funnel glass could be recovered after mechanochemical reduction with aluminum. Lead chloride (PbCl2) can be recycled from the leaching solution after cooling crystallization. Nano-sized Pb formation and the structural changes of leaded CRT funnel glass by mechanochemical reduction process contributed to obvious improvement in lead recovery. This research provided a high-efficiency and feasible approach for recovering lead in form of PbCl2 crystal from leaded glass.


Subject(s)
Cathode Ray Tube , Electronic Waste , Powders , Aluminum , Lead , Electronic Waste/analysis , Glass/chemistry
2.
Chemosphere ; 212: 540-547, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30165280

ABSTRACT

In this research, mechanochemical reduction was carried out to remediate Cr(VI) contaminated soil, and the reduction effectiveness was evaluated by analyzing the corresponding leachable fraction obtained through the toxicity characteristic leaching procedure (TCLP) proposed by the EPA. The results indicated that mechanochemical reduction can efficiently reduce the Cr(VI) concentration in the leachate. Under a milling time of 2 h, milling speed of 500 rpm, ball-to-powder weight ratio of 14 and Na2S dosage of 5%, the Cr(VI) leaching concentration significantly decreased from 663.98 mg L-1 to 0.84 mg L-1, much lower than the regulatory limit of 5 mg L-1. In addition, the significant decrease in Cr(VI) was mainly due to the reduction of Cr(VI) to Cr(III), as supported by X-ray photoelectron spectroscopy (XPS). The mechanochemical reduction with mechanism proposed in this experiment may involve two major processes: solidification and reduction (stabilization).


Subject(s)
Chromium/chemistry , Environmental Pollution/analysis , Environmental Restoration and Remediation/methods , Soil Pollutants/chemistry , Soil/chemistry , Sulfides/chemistry , Soil Pollutants/analysis
3.
Anal Chim Acta ; 1014: 64-70, 2018 Jul 19.
Article in English | MEDLINE | ID: mdl-29523253

ABSTRACT

Antipsychotics are the drugs most often involved in drug poisoning cases, and therefore, therapeutic drug monitoring (TDM) is necessary for safe and effective medication administration of these drugs. In this study, a coffee ring effect-based surface-enhanced Raman spectroscopy (CRE-SERS) method was developed and successfully used to monitor antipsychotic poisoning by using urine samples for the first time. The established method exhibited excellent SERS performance since more hot spots were obtained in the "coffee ring". Using the optimized CRE-SERS method, the sensitivity was improved one order more than that of the conventional method with reasonable reproducibility. The antipsychotic drug clozapine (CLO) spiked into urine samples at 0.5-50 µg mL-1 was quantitatively detected, at concentrations above the thresholds for toxicity. The CRE-SERS method allowed CLO and its metabolites to be ultimately distinguished from real poisoning urine samples. The coffee-ring effect would provide more opportunities for practical applications of the SERS-based method. The frequent occurrence of drug poisoning may have created a new area for the application of the CRE-SERS method. It is anticipated that the developed method will also have great potential for other drug poisoning monitoring.


Subject(s)
Antipsychotic Agents/urine , Clozapine/urine , Animals , Antipsychotic Agents/poisoning , Clozapine/poisoning , Male , Rats , Rats, Sprague-Dawley , Spectrum Analysis, Raman , Surface Properties
4.
Kaohsiung J Med Sci ; 33(8): 369-378, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28811005

ABSTRACT

The study aims to explore how microRNA-146a/b (miR-146a/b) regulates the function of endothelial progenitor cells (EPCs) in acute ischemic stroke in mice. Eighty male SPF C57BL/6J mice were evenly divided into the model-6 h, model-12 h, model-24 h (mice suffered from middle cerebral artery occlusion [MCAO] for 6 h, 12 h and model-24 h) and normal groups. EPCs were transfected and assigned into the control, MCAO, MCAO-miR-146a, MCAO-miR-146b and MCAO-miR-146a/b groups. The qRT-PCR was used to detect miR-146a/b expression in EPCs. Expressions of tumor necrosis factor receptor-associated factor 6 (TRAF6) and interleukin-1 receptor-associated kinase 1 (IRAK1) were detected using western blotting. Cell proliferation and migration of EPCs were testified using CCK-8 assay and scratch test, respectively. Angiogenesis ability of EPCs was observed under microscope. MiR-146a and miR-146b expressions were lower in the model groups than the normal group. There were up-regulated TRAF6 and IRAK1 expressions in the model-6 h, model-12 h and model-24 h groups compared with the normal group. And there were down-regulated TRAF6 and IRAK1 expressions in the MCAO-miR-146a, MCAO-miR-146b and MCAO-miR-146a/b groups than in the MCAO group. Compared with the control group, the proliferation, migration and angiogenesis ability of EPCs were significantly lower in the MCAO group, but higher in the MCAO-miR-146a, MCAO-miR-146b and MCAO-miR-146a/b groups. Besides, the miR-146a/b group showed more enhancement than the MCAO-miR-146a and MCAO-miR-146b groups. MiR-146a/b could down-regulate the TRAF6 and IRAK1 expressions and promote proliferation, migration and angiogenesis ability of EPCs, which was important for recovery of patients with hyperacute ischemic stroke.


Subject(s)
Brain Ischemia/genetics , Endothelial Progenitor Cells/metabolism , Interleukin-1 Receptor-Associated Kinases/genetics , MicroRNAs/genetics , Stroke/genetics , TNF Receptor-Associated Factor 6/genetics , Animals , Brain Ischemia/metabolism , Brain Ischemia/pathology , Brain Ischemia/therapy , Cell Movement , Cell Proliferation , Cerebrovascular Disorders/surgery , Disease Models, Animal , Endothelial Progenitor Cells/cytology , Gene Expression Regulation , Humans , Interleukin-1 Receptor-Associated Kinases/metabolism , Male , Mice , Mice, Inbred C57BL , MicroRNAs/metabolism , Middle Cerebral Artery/surgery , Neovascularization, Physiologic/genetics , Plasmids/chemistry , Plasmids/metabolism , Signal Transduction , Stroke/metabolism , Stroke/pathology , Stroke/therapy , TNF Receptor-Associated Factor 6/metabolism , Transfection
6.
Zhonghua Xin Xue Guan Bing Za Zhi ; 40(1): 8-13, 2012 Jan.
Article in Chinese | MEDLINE | ID: mdl-22490626

ABSTRACT

OBJECTIVE: To compare the effects of valsartan combined with amlodipine or hydrochlorothiazide regimen on blood pressure variation and plasma nitric oxide (NO) and endothelin (ET) in elderly hypertensive patients. METHODS: A total of 61 elderly patients with grade 2 or 3 hypertension were randomized into valsartan + amlodipine (the amlodipine group, n = 31) or valsartan + hydrochlorothiazide (the hydrochlorothiazide group, n = 30) group. Blood lipids, fasting plasma glucose and uric acid were determined before the treatment. 24-hour dynamic blood pressure, NO and ET were monitored at baseline, 8 and 16 weeks after treatment. RESULTS: 24 hours blood pressure and daytime blood pressure were similar between two groups at all 3 time points. At 16 weeks, morning systolic blood pressure surge was significantly lower in amlodipine group than in hydrochlorothiazide group [(22.6 ± 8.8) mm Hg (1 mm Hg = 0.133 kPa) vs. (26.3 ± 13.7) mm Hg, P < 0.05]. 24 hours systolic blood pressure variability (SBPV) decreased progressively in both groups [the amlodipine group: (12.5 ± 2.8) mm Hg vs. (10.2 ± 2.2) mm Hg vs. (8.8 ± 1.6) mm Hg, P < 0.01; the hydrochlorothiazide group: (12.5 ± 2.5) mm Hg vs. (10.7 ± 2.2) mm Hg vs. (9.6 ± 2.0) mm Hg, P < 0.01]. Daytime SBPV also decreased progressively in both groups [the amlodipine group: (12.2 ± 3.0) mm Hg vs. (10.1 ± 2.3) mm Hg vs. (8.4 ± 1.9) mm Hg, P < 0.01; the hydrochlorothiazide group: (11.8 ± 2.7) mm Hg vs. (10.4 ± 1.9) mm Hg vs. (9.6 ± 2.2) mm Hg, P < 0.01]. 24 hours diastolic blood pressure variability (DBPV) was significantly reduced post therapy in the amlodipine group [(15.5 ± 3.4) mm Hg vs. (13.0 ± 3.5) mm Hg vs. (12.3 ± 2.5), P < 0.01] but not in the hydrochlorothiazide group. NO increased progressively [(27.3 ± 13.6) µmol/L vs. (47.2 ± 16.3) µmol/L vs. (69.5 ± 18.9) µmol/L in the amlodipine group, P < 0.01; (33.5 ± 13.9) µmol/L vs. (49.7 ± 21.9) µmol/L vs. (66.7 ± 24.7) µmol/L in the hydrochlorothiazide group, P < 0.01] and ET decreased progressively [(45.3 ± 8.0) ng/L vs. (37.4 ± 3.9) ng/L vs. (34.2 ± 4.4) ng/L in the amlodipine group, P < 0.01; (46.6 ± 10.4) ng/L vs. (37.0 ± 5.4) ng/L vs. (36.1 ± 8.2) ng/L in the hydrochlorothiazide group, P < 0.01] in both groups. CONCLUSION: Valsartan in combination with amlodipine or hydrochlorothiazide can both effectively lower BPV in elderly hypertensive patients and improve the vascular endothelial function and the former regimen is more suitable for elderly hypertensive patients.


Subject(s)
Hypertension/drug therapy , Hypertension/physiopathology , Tetrazoles/therapeutic use , Valine/analogs & derivatives , Aged , Amlodipine/therapeutic use , Blood Pressure/drug effects , Drug Therapy, Combination , Female , Humans , Hydrochlorothiazide/therapeutic use , Male , Middle Aged , Treatment Outcome , Valine/therapeutic use , Valsartan
7.
Zhonghua Yi Xue Za Zhi ; 89(40): 2862-6, 2009 Nov 03.
Article in Chinese | MEDLINE | ID: mdl-20137670

ABSTRACT

OBJECTIVE: To explore the effects of atrial natriuretic peptide (ANP) upon the activities of Na(+), K(+)-ATPase, Ca(2+)-ATPase and mRNA expression levels of Na(+), K(+)-ATPase alpha(1)-subunit and plasma membrane Ca(2+)-ATPase isoform 1 (PMCA1) in cultured thoracic aortic vascular smooth muscle cells (ASMCs) isolated from spontaneously hypertensive rats (SHR). METHODS: ASMCs isolated from 14-week-old male SHR and Wistar-Kyoto (WKY) rats were interference-cultured in different doses of ANP and Angiotensin II (AngII). The contents of ANP and AngII in supernatant from ASMCs were measured by radioimmunoassay. The activities of the above two ATPases were measured by biochemistry and enzymology. RT-PCR assay was employed to determine the relative levels of Na(+), K(+)-ATPase alpha(1)-subunit and PMCA1 mRNA in ASMCs. RESULTS: The ANP level of supernatant in SHR ASMCs was significantly lower than those from WKY control [(7.3 +/- 2.4) pg x 10(-6) cells vs (19.3 +/- 3.3) pg x 10(-6) cells, P < 0.01] while the content of AngII in SHR ASMCs was significantly higher than those from WKY control [(57 +/- 4) pg x 10(-6) cells vs (44 +/- 4) pg x 10(-6) cells, P < 0.01]. The activity of Na(+), K(+)-ATPase [(4.3 +/- 0.8) micromol x h(-1) x mg(-1) vs (5.3 +/- 1.0) micromol x h(-1) x mg(-1)], Ca(2+)-ATPase [(3.2 +/- 0.7) micromol x h(-1) x mg(-1) vs (4.5 +/- 0.7) micromol x h(-1) x mg(-1)] in ASMCs from SHR were significantly lower than those from WKY control (both P < 0.01). The mRNA expression of Na(+), K(+)-ATPase alpha(1)-subunit (0.524 +/- 0.025 vs 0.704 +/- 0.116), PMCA1 (0.193 +/- 0.030 vs 0.547 +/- 0.045) significantly decreased in ASMCs from SHR versus the WKY control (both P < 0.01). As compared with SHR control, exogenous ANP improved obviously the activities of Na(+), K(+)-ATPase, Ca(2+)-ATPase and expression of alpha(1)-subunit, PMCA1 mRNA in a does-dependent manner (P < 0.05-P < 0.01). Exogenous AngII (1 x 10(-9), 1 x 10(-8), 1 x 10(-7) mol/L) significantly repressed activities of Ca(2+)-ATPase and attenuated the expression of PMCA1 mRNA (P < 0.05-P < 0.01). Only AngII (1 x 10(-7) mol/L) significantly inhibited the activity of Na(+), K(+)-ATPase and attenuated the expression of Na(+), K(+)-ATPase alpha(1)-subunit mRNA (both P < 0.05). ANP antagonized the effects of AngII (1 x 10(-7) mol/L) upon the activities of two ATPases and the expression of Na(+), K(+)-ATPase alpha(1)-subunit PMCA1 mRNA (P < 0.05-P < 0.01). AngII (1 x 10(-7) mol/L) increased the Na(+), K(+)-ATPase activity and the expression of Na(+), K(+)-ATPase alpha(1)-subunit mRNA, repressed the Ca(2+)-ATPase activity and the expression of PMCA1 mRNA in ASMCs from WKY rat (P < 0.05-P < 0.01). ANP antagonized the effects of AngII (1 x 10(-7) mol/L) upon the activity of Ca(2+)-ATPase and the expression of PMCA1 mRNA (P < 0.05-P < 0.01), but did not antagonize the effects of AngII (1 x 10(-7) mol/L) upon the activity of Na(+), K(+)-ATPase and the expression of alpha(1)-subunit mRNA in ASMCs from WKY rats (P > 0.05). CONCLUSION: The decreased activities of Na(+), K(+)-ATPase and Ca(2+)-ATPase may be related to the abnormal autocrine of ANP and AngII in ASMC of SHR. ANP can antagonize the effects of AngII upon the activities of two ATPases and the expression of Na(+), K(+)-ATPase alpha(1)-subunit PMCA1 mRNA.


Subject(s)
Atrial Natriuretic Factor/pharmacology , Gene Expression/drug effects , Ion Pumps/drug effects , Myocytes, Smooth Muscle/metabolism , Animals , Aorta/cytology , Ion Pumps/metabolism , Male , Muscle, Smooth, Vascular/metabolism , Rats , Rats, Inbred SHR , Rats, Inbred WKY
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