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1.
Arch Environ Contam Toxicol ; 79(2): 246-257, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32607658

ABSTRACT

In this work, rare minnow (Gobiocypris rarus) was applied as a sentinel organism and set in cages at control and test sampling sites in Donghu Lake for 4 weeks in March, June, September, and December 2016 to assess the biological toxicity of in situ water. Sampling for active biomonitoring and physicochemical variables was performed weekly. The control was obtained from the outdoor pool of the Institute of Hydrobiology, China. Superoxide dismutase, lipoperoxidation, metallothioneins, acetylcholinesterase activity, and Vtg mRNA expression were determined as biomarkers during the field exposure period. Survival and growth also were monitored to evaluate the overall physiological condition of the fish. The seasonal changes of organic pollutants and trace metals (As, Hg, Cr, Cu, Zn, Cd, Pb) in surface water were determined. The integrated biomarker response (IBR) index was applied to summarize biomarker responses and correlate stress levels with concentrations of organic pollutants and trace metals in the surface water. Results indicated that complex pollution by persistent organic pollutants and heavy metals was present in Donghu Lake and that the in situ exposed organisms were stressed. Moreover, the complex pollution of Donghu Lake in summer and autumn was more serious than that in spring and winter. Active biomonitoring combined with IBR analysis enabled good discrimination among different exposure seasons. The proposed protocol with caged rare minnow revealed marked biological effects caused by the investigated Lake and a useful approach that can easily be extended to monitor water pollution.


Subject(s)
Cyprinidae/physiology , Environmental Monitoring , Water Pollutants, Chemical/metabolism , Animals , China , Cyprinidae/growth & development , Environmental Pollution/analysis , Lakes/chemistry , Mercury/analysis , Metallothionein , Metals, Heavy/analysis , Water Pollutants, Chemical/analysis
2.
ACS Appl Mater Interfaces ; 12(25): 28539-28549, 2020 Jun 24.
Article in English | MEDLINE | ID: mdl-32492327

ABSTRACT

In this work, we reported a multi-responsive luminescent hydrogel with properties of encryption, naked eye sensing of glucose, shape memory, self-healing, and antibacterial activity. The hydrogel (GA/CCS/DNSA/Eu3+) was obtained by mixing phenylboronic acid-modified gelatin (GA-DBA), catechol-modified carboxymethyl chitosan (CCS-PCA), 3,5-dinitrosalicylic acid (DNSA), and Eu3+ ions through a facile heating-cooling process. The resultant hydrogel exhibits reversible luminescence and color and phase changes in response to temperature, acid/base, salt, and redox stimuli. Based on the multiple responsiveness, information encryption and decryption, naked eye sensing of glucose, remarkable shape memory, and enhanced mechanical properties of the as-prepared hydrogel were realized. In addition, the self-healing capacity was also achieved due to the dynamic bonds in GA/CCS/DNSA/Eu3+ hydrogels. Specifically, the GA/CCS/DNSA/Eu3+ hydrogels possess antibacterial activity owing to the bacteriostasis of the CCS-PCA and DNSA/Eu3+ complex. Thus, GA/CCS/DNSA/Eu3+ hydrogels have potential applications in the fields of anticounterfeiting, wearable devices, biomedicine, sensing, etc.


Subject(s)
Anti-Bacterial Agents/chemistry , Hydrogels/chemistry , Lanthanoid Series Elements/chemistry , Boronic Acids/chemistry , Catechols/chemistry , Gelatin/chemistry , Luminescence , Prostheses and Implants
3.
Anal Chim Acta ; 1110: 11-18, 2020 May 08.
Article in English | MEDLINE | ID: mdl-32278385

ABSTRACT

The analysis of siliceous matrix samples may adopt a two-step pretreatment, which includes melting with ammonium hydrogen fluoride and redissolving with nitric acid. However, the residual of substrate silicon unfavorable to the determination of trace elements in the samples due to serious matrix effects. Here, a new digestion method using simultaneously both ammonium bifluoride and nitric acid under normal pressure was developed for high-purity quartz sand sample. The digestion pretreatment is a two step process: melting/dissolving with both ammonium bifluoride and nitric acid at 200 °C for 2 h, and evaporating the solution at 250 °C to dryness. As confirmed by XRD analysis, silicates in the sample were converted to (NH4)3SiF6NO3 in the melting/dissolving step. TGA analysis shows that the generated (NH4)3SiF6NO3 could be decomposed and evaporated completely at 250 °C, which ensured a complete removal of silicon by the followed evaporation of the solution at 250 °C. As a result, the followed ICP-OES and ICP-MS analysis needed a solution dilution of only 100 times for the determination of Ca, Mg, Al, Rb, Ba, REE and other trace elements. The new method was applied to the analysis of three certified reference materials, and the results were well consistent with the standard value with RSD% values between 0.62% and 9.73%. Therefore, this method can be applied to the analysis of trace elements in high purity silica-based samples, with the advantages of time-saving, small dilution factor (only 100 times) and low detection limit.

4.
Dalton Trans ; 49(9): 2827-2832, 2020 Mar 03.
Article in English | MEDLINE | ID: mdl-32065177

ABSTRACT

Preparing luminescence-stable lanthanide materials in a facile manner has always been an intriguing challenge. Herein we report an easy approach to the preparation of a heat-set lanthanide-based metallogel (H6L/Tb gel) with stable luminescence from 5,5',5''-(1,3,5-triazine-2,4,6-triyl)tris(azanediyl) triisophthalate (H6L) as a Tb3+ coordinating ligand. The heat-set H6L/Tb gel exhibits luminescence that mostly retains its intensity in the 0-90 °C temperature range and under mechanical stimulus. In addition, the H6L/Tb xerogel is also luminescent in aqueous solution. UV-vis and FT-IR spectroscopy and XRD studies reveal that the stable luminescence of the H6L/Tb gel depends on heat-set-induced strong hydrogen bonding, π-π stacking, and metal-ligand interactions. This study provides a heat-set approach to the preparation of luminescence-stable metallogel materials, such metallogels are potentially useful in anti-counterfeiting and sensing fields, among others.

5.
Acta Cir Bras ; 34(8): e201900805, 2019.
Article in English | MEDLINE | ID: mdl-31618405

ABSTRACT

PURPOSE: To investigate the effect of sevoflurane preconditioning on ischemia/reperfusion (I/R)-induced pulmonary/hepatic injury. METHODS: Fifty-one Wistar rats were randomly grouped into sham, I/R, and sevoflurane groups. After reperfusion, the structural change of the lung was measured by Smith score, the wet and dry weights (W/D) were determined, malondialdehyde (MDA) myeloperoxidase (MPO) content was determined colorimetrically and by fluorescence, respectively, and matrix metalloprotein-9 (MMP-9) mRNA was quantified by RT-PCR. Biopsy and morphological analyses were performed on liver tissue, activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were determined, and tumor necrosis factor-alpha (TNF-α) level was determined. RESULTS: The sham group showed no changes in tissue structure. Structural lesions in the sevoflurane and I/R groups were mild and severe, respectively. Smith score, W/D, MDA, MPO, and MMP mRNA showed the same trend, and were increased in the I/R group and recovered in the sevoflurane group, compared with the sham group (both P<0.05). AST and ALT were significantly increased compared to the sham group (AST: 655±52.06 vs . 29±9.30 U/L; ALT: 693±75.56 vs . 37±6.71 U/L; P<0.05). In the sevoflurane group, AST and ALT levels were significantly decreased (464±47.71 and 516±78.84 U/L; P<0.001). TNF-α presented similar results. CONCLUSION: The protection of lung and liver by sevoflurane may be mediated by inhibited leukocyte recruitment and MMP-9 secretion.


Subject(s)
Anesthetics, Inhalation/therapeutic use , Ischemic Preconditioning/methods , Liver/blood supply , Lung/blood supply , Reperfusion Injury/prevention & control , Sevoflurane/therapeutic use , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Disease Models, Animal , Ischemia/prevention & control , Liver/drug effects , Liver/pathology , Lung/drug effects , Lung/pathology , Male , Malondialdehyde/analysis , Peroxidase/analysis , Rats , Rats, Wistar , Reperfusion Injury/drug therapy , Tumor Necrosis Factor-alpha/blood
6.
Acta cir. bras ; 34(8): e201900805, 2019. tab, graf
Article in English | LILACS | ID: biblio-1038124

ABSTRACT

Abstract Purpose To investigate the effect of sevoflurane preconditioning on ischemia/reperfusion (I/R)-induced pulmonary/hepatic injury Methods Fifty-one Wistar rats were randomly grouped into sham, I/R, and sevoflurane groups. After reperfusion, the structural change of the lung was measured by Smith score, the wet and dry weights (W/D) were determined, malondialdehyde (MDA) myeloperoxidase (MPO) content was determined colorimetrically and by fluorescence, respectively, and matrix metalloprotein-9 (MMP-9) mRNA was quantified by RT-PCR. Biopsy and morphological analyses were performed on liver tissue, activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were determined, and tumor necrosis factor-alpha (TNF-α) level was determined. Results The sham group showed no changes in tissue structure. Structural lesions in the sevoflurane and I/R groups were mild and severe, respectively. Smith score, W/D, MDA, MPO, and MMP mRNA showed the same trend, and were increased in the I/R group and recovered in the sevoflurane group, compared with the sham group (both P<0.05). AST and ALT were significantly increased compared to the sham group (AST: 655±52.06 vs . 29±9.30 U/L; ALT: 693±75.56 vs . 37±6.71 U/L; P<0.05). In the sevoflurane group, AST and ALT levels were significantly decreased (464±47.71 and 516±78.84 U/L; P<0.001). TNF-α presented similar results. Conclusion The protection of lung and liver by sevoflurane may be mediated by inhibited leukocyte recruitment and MMP-9 secretion.


Subject(s)
Animals , Male , Rats , Reperfusion Injury/prevention & control , Anesthetics, Inhalation/therapeutic use , Ischemic Preconditioning/methods , Liver/blood supply , Lung/blood supply , Aspartate Aminotransferases/blood , Reperfusion Injury/drug therapy , Tumor Necrosis Factor-alpha/blood , Peroxidase/analysis , Alanine Transaminase/blood , Disease Models, Animal , Sevoflurane/therapeutic use , Ischemia/prevention & control , Liver/drug effects , Liver/pathology , Lung/drug effects , Lung/pathology , Malondialdehyde/analysis
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