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1.
Artigo em Inglês | MEDLINE | ID: mdl-35389820

RESUMO

The objective of this study was to assess the association of exposure to metal mixtures with semen quality and sperm DNA integrity of coke oven workers (n = 96). Urinary six metals (cadmium, lead, arsenic, zinc, selenium, and copper) were quantified using inductively coupled-mass spectrometry. Semen quality parameters included sperm concentration, sperm concentration, sperm motility, sperm morphology, and sperm viability. Sperm DNA fragmentation and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) adducts served as biomarkers for assessing sperm DNA integrity. Bayesian kernel machine regression with the hierarchical variable selection process was used for analyzing both individual and joint effects of the metal mixture on the outcomes of semen samples, while adjusting for age, smoking, alcohol consumption, job length, and body mass index. The metal mixture was associated with reduced sperm concentration, motility, viability, and normal morphology. It was novel that a dose-response relationship was observed between exposure of the metal mixture and semen quality. Among the metals tested, cadmium had a reverse relationship with sperm motility, viability, and normal morphology, and a non-linear relationship with sperm viability and sperm motility. The metal mixture and individual metals were not associated with sperm DNA fragmentation and 8-oxodGuo. In conclusion, exposure to metal mixtures and cadmium may exert an association with semen quality and had no association with sperm DNA breakages.


Assuntos
Análise do Sêmen , Motilidade dos Espermatozoides , 8-Hidroxi-2'-Desoxiguanosina , Teorema de Bayes , Cádmio/análise , DNA , Humanos , Masculino , Metais/análise , Sêmen , Espermatozoides
2.
Langmuir ; 37(23): 7147-7155, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34081475

RESUMO

We disclose a straightforward approach to fabricate nanocomposites for efficient capture of Cr(VI) from an aqueous solution through the self-assembly of poly(ethyleneimine)-modified graphitic carbon nitride nanosheets (PEI-g-C3N4 NSs) and lysozyme fibrils (LFs). The as-made PEI-g-C3N4 NSs@LFs exhibited mesoporous structures with a high specific surface area of 39.6 m2 g-1, a large pore volume of 0.25 cm3 g-1, several functional groups (e.g., -N, -NH, -NH2, and -COOH), and a zero-point charge at pH 9.1. These merits allow the PEI-g-C3N4 NSs@LFs to further enhance their physical adsorption and electrostatic attraction with the negatively charged Cr(VI) species of HCrO4- and CrO42-, which is beneficial for the uptake of Cr(VI), >80%, from an aqueous solution in a wide pH range. Interestingly, X-ray photoelectron spectra indicate that the PEI-g-C3N4 NSs@LFs converted Cr(VI) to Cr(III) through visible-light-induced photoreduction. The adsorption of Cr(VI) on the surface of PEI-g-C3N4 NSs@LFs was found to obey the Freundlich isotherm model, signifying that they have a heterogeneous surface for the multilayer uptake of Cr(VI). In contrast, the PEI-g-C3N4 NSs and LFs as Cr(VI) adsorbents followed the Langmuir isotherm model. Adsorption kinetic studies showed that the uptake of Cr(VI) through the PEI-g-C3N4 NSs@LFs was highly correlated with a pseudo-first-order model, suggesting that physisorption dominates the interaction of Cr(VI) and the PEI-g-C3N4 NSs@LFs. In real-life applications, the PEI-g-C3N4 NSs@LFs were used for the detoxification of the total chromium in the industrial effluent and sludge samples.

3.
Helicobacter ; 23(2): e12460, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29315971

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection causes elevation of lipid peroxidation product malondialdehyde (MDA) and this association may be due to the bacterium causing reactive oxygen species-mediated damage to DNA in the gastric epithelium. The aim of this study was to investigate the gastric juice MDA levels in relation to H. pylori infection and associated gastric diseases. METHODS: Gastric juice samples were obtained from 117 patients undergoing endoscopy, and gastric juice MDA levels were determined by high-performance liquid chromatography (HPLC) system. We compared the MDA levels between patients with and without H. pylori infection and assessed the differences of MDA levels between chronic gastritis, gastric intestinal metaplasia, and gastric cancer postsurgical resection. RESULTS: Malondialdehyde levels in gastric juice were significantly higher in chronic gastritis patients with H. pylori infection than in those without H. pylori infection (P < .0001). In patients without H. pylori infection, patients with gastric intestinal metaplasia and gastric cancer postsurgical resection had significantly higher gastric juice MDA level than patients with chronic gastritis. As a whole, patients with gastric intestinal metaplasia and gastric cancer postsurgical resection also had significantly higher MDA levels in gastric juice as compared to patients with chronic gastritis (P < .01). However, the difference of gastric juice MDA levels between gastric intestinal metaplasia and gastric cancer postsurgical resection was not significant. CONCLUSION: Malondialdehyde in gastric juice could be used as a potential diagnostic biomarker for H. pylori infection and associated gastric diseases. The gastric juice MDA levels increased proportionally with the severity of gastric diseases.


Assuntos
Suco Gástrico/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori/patogenicidade , Malondialdeído/metabolismo , Idoso , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Gastrite/metabolismo , Gastrite/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiologia
4.
Analyst ; 142(24): 4737-4743, 2017 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-29124255

RESUMO

In this study, a microdialysis (MD) technique was combined with high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for continuous monitoring of the dynamic variations of arsenic species in a microbe-inoculated culture broth. After optimizing the analytical system, retrodialysis was applied to assess the probe recovery and analytical performance of the proposed method. The mean probe recoveries of four arsenic species were in the range from 57.0 to 81.8%. The limit of detection (LOD) for arsenic was in the range of 0.6-1.8 ng mL-1 and 0.032 µM for MDA, respectively. The accuracy was assessed by an addition/recovery test with a satisfactory value of 98.07-109.08% for arsenic species and 93.57-108.15% for MDA, respectively. To evaluate the practical applicability of this method, we monitored, continuously for 72 h, the dynamic variations of the concentrations of the four arsenic species in a standardized bacterial sample (ATCC 25922). After adding the arsenic species into the bacteria-inoculated broth, we found that the concentration of As3+ decreased over time, whereas As5+ increased in concentration. In addition, malondialdehyde (MDA) was also monitored to evaluate the effect of oxidative damage of the arsenic species on the studied microbial system. Our analyses revealed that the dynamic variations of the arsenic species and MDA could be observed continuously during the microbial growth period. This economical and eco-friendly method might also be helpful for monitoring the transformations of other metal species, oxidation processes, and the bioremediation ability of microbial systems.


Assuntos
Arsênio/metabolismo , Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Microdiálise , Biotransformação , Limite de Detecção , Malondialdeído , Estresse Oxidativo
5.
Curr Opin Clin Nutr Metab Care ; 18(6): 588-92, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26406393

RESUMO

PURPOSE OF REVIEW: Chromium, zinc, and magnesium are involved in insulin signal transduction, glucose metabolism, and cellular antioxidative defense. This review details the statuses of chromium, zinc, and magnesium in type 1 diabetes patients. RECENT FINDINGS: Blood levels of trace elements (especially magnesium and zinc) were lower in type 1 diabetes patients than in controls and were even lower in type 1 diabetes patients with poor glycemic control. Studies with mouse models have shown that chromium and magnesium supplementation alleviated diabetes-induced complications and improved glycemic control. SUMMARY: Many studies indicated positive correlations between decreased levels of serum chromium, zinc, and magnesium and poor glycemic control. The supplementation of type 1 diabetes patients with zinc, magnesium, and chromium may help to control diabetes and prevent diabetes-related oxidative injuries, but require further study.


Assuntos
Glicemia/metabolismo , Cromo , Diabetes Mellitus Tipo 1/sangue , Magnésio , Estado Nutricional , Oligoelementos , Zinco , Animais , Cromo/sangue , Cromo/deficiência , Complicações do Diabetes/sangue , Diabetes Mellitus Tipo 1/complicações , Suplementos Nutricionais , Humanos , Magnésio/sangue , Deficiência de Magnésio/sangue , Estresse Oxidativo , Oligoelementos/sangue , Oligoelementos/deficiência , Zinco/sangue , Zinco/deficiência
6.
Rapid Commun Mass Spectrom ; 29(2): 163-70, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25641491

RESUMO

RATIONALE: Conventional mass spectrometry is encumbered by laborious and inconvenient sample pretreatment. Ambient thermal desorption electrospray ionization mass spectrometry (TD-ESI-MS) is most noted for its rapid, simple, and sensitive detection capabilities. In this study, TD-ESI-MS was used to rapidly characterize residual pesticides on the surfaces of fruits and vegetables. METHODS: A direct sampling probe was used to obtain analytes from sample surfaces. MS and MS/MS analyses were performed on fruits and vegetables via TD-ESI-MS. External calibration curves and reproducibility tests were performed using liquid pesticide standards. Pesticide decay and distribution on samples was studied, as well as the removal of residual pesticides via soaking in water or detergent baths. RESULTS: Since sample pretreatment was unnecessary, an analysis was completed in approximately 15 s or less, with no visible sample damage. Mass spectra were obtained for 22 pesticides. Linear calibrations (R(2) from 0.9414-0.999) had limits of detection as low as 0.5 µg·L(-1), with satisfactory reproducibilities for liquids and solids. Pesticides on sample surfaces decayed over 2 weeks under ambient conditions. Residual pesticides localized at the fruit peel. Detergent baths removed more pesticide than water baths. CONCLUSIONS: TD-ESI-MS was used to rapidly screen residual pesticides in liquids and solids. Pesticides were found on fruits and vegetables, where the decay, distribution, and removal of pesticides on samples were also explored. Due to short analysis times, the technique allows for high-throughput analyses for applications in food and environmental safety.


Assuntos
Frutas/química , Resíduos de Praguicidas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Verduras/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Água
7.
Int J Environ Health Res ; 25(4): 405-17, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25269935

RESUMO

The objective of the study was to examine the associations between environmentally relevant low metal concentrations and semen quality parameters in men. The concentrations of zinc (Zn), copper (Cu), cadmium (Cd), arsenic (As), selenium (Se), and lead (Pb) in the seminal plasma and urine were measured from 196 male human subjects in Taiwan. Urinary Cd concentrations were negatively associated with sperm viability (p = 0.006). Seminal plasma Cu concentrations of the normal group (≥ 15 × 10(6)/ml) were significantly lower than those of the abnormal group (p = 0.023). However, the linear regression analysis showed a weak association between Cu concentration and sperm concentration, along with other semen parameters. No significant relationship between other metals (As, Pb, Zn, and Se) and semen quality was observed.


Assuntos
Poluentes Ambientais/toxicidade , Metais/toxicidade , Análise do Sêmen , Sêmen/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Adulto , Idoso , Arsênio/sangue , Arsênio/toxicidade , Arsênio/urina , Poluentes Ambientais/sangue , Poluentes Ambientais/urina , Humanos , Masculino , Metais/sangue , Metais/urina , Metais Pesados/sangue , Metais Pesados/toxicidade , Metais Pesados/urina , Pessoa de Meia-Idade , Selênio/sangue , Selênio/toxicidade , Selênio/urina , Contagem de Espermatozoides , Taiwan , Adulto Jovem
8.
Chemosphere ; 351: 141170, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219989

RESUMO

The present study highlights heavy metal tolerance, EPS production, and biosorption capacity of four hydrothermal vent bacterial strains, namely Exiguobacterium aquaticum, Mammaliicoccus sciuri, Micrococcus luteus, and Jeotgalicoccus huakuii against As, Cd, Cr, Cu, Co, Pb and Ni. The biosorption assay showed high removal efficiency of As (83%) by E. aquaticum, Cd (95%) by M. sciuri, Cu (94%) by M. luteus, and Ni (89%) by J. huakuii and their produced EPS with these metals in aqueous solution were 84%, 85%, 98%, and 91%, respectively. The maximum EPS yield was attained by optimized medium composition consisting of 1% Xylose, and 1% NaCl at pH 7. In metal-amended conditions, the four bacterial strains showed induced EPS production in the initial concentrations. SEM with EDX and CLSM images showed that the growth and EPS production of bacterial strains were affected by metal ion concentrations. A phenol sulphuric acid method and BCA assay were used to identify both the carbohydrate and total protein content of four extracted EPS. A DPPH assay revealed that EPS influences free radical scavenging and has a highly enhanced synergistic effect with its antioxidant activity. FT-IR analysis of four extracted EPS showed the shifting of peaks in the functional groups of EPS before and after adsorption of metal ions. At pH 5 and after 60 min contact time metal removal efficiency and adsorption capacity increased as calculated for As, Cd, Cu, and Ni by four extracted EPS: (86%, 20 mg/g), (74%, 19 mg/g), (94%, 60 mg/g) and (89%, 32 mg/g) and (89%, 16 mg/g), (85%, 16 mg/g), (96%, 22 mg/g) and (91%, 16 mg/g), respectively. The Langmuir compared to the Freundlich model was found to better represent the adsorption by EPS providing maximum adsorption capacities for As (34.65 mg/g), Cd (52.88 mg/g), Cu (24.91 mg/g), and Ni (58.38 mg/g).


Assuntos
Fontes Hidrotermais , Metais Pesados , Cádmio/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Metais Pesados/análise , Bactérias/metabolismo , Íons , Adsorção , Concentração de Íons de Hidrogênio , Cinética
9.
Int J Biol Macromol ; 276(Pt 1): 133767, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38986989

RESUMO

To address the increasing demand for sensitive and selective sample preparation methods for metal analysis; preconcentration of intended analyte from complex sample matrices before analysis is required to improve the performance of analysis instruments. In this study, we have engineered a sustainable and portable syringe-based hand-operable three-dimensionally (3D) printed sample pretreatment apparatus equipped with a replaceable bio-based thin- film metal sorbent. This device effectively addresses the challenges of sample matrix interference in metal analysis. A metal sorbent film composed of chitosan (CS) and polydopamine (PDA) leveraged the diverse functional groups in the CS/PDA matrix to significantly enhance the extraction efficiency for various metals. Our approach demonstrated excellent analytical performance, with coefficients of determination (R2) of 0.9982 for copper (Cu) and 0.996 for chromium (Cr). The method achieved low limits of detection (LOD) of 0.3 µg L-1 for Cr and 0.7 µg L-1 for Cu. Precision and practicality assessments using actual urine samples yielded satisfactory relative standard deviations (RSD%) ranging from of 1.6 %-8.5 % for both metals, indicating minimal interference from the sample matrix. Moreover, our approach exhibited robust performance even after seven consecutive extraction and desorption cycles, highlighting its sustainability and practical applicability for laboratory and on-site sample pretreatment.


Assuntos
Quitosana , Indóis , Polímeros , Impressão Tridimensional , Quitosana/química , Polímeros/química , Indóis/química , Cobre/química , Humanos , Limite de Detecção , Cromo/isolamento & purificação , Cromo/análise , Cromo/urina , Adsorção , Metais/química , Miniaturização
10.
Anal Chim Acta ; 1310: 342672, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811131

RESUMO

BACKGROUND: This study tackles the critical challenges in metal analysis by presenting an innovative miniaturized metal extraction device prototype. This device features a functional nanocomposite (FNC) enhanced 3D-printed polylactic acid (PLA) metal extractant (FNC@3D PLA). The research is motivated by the constraints of traditional solid-phase extraction (SPE) methods, specifically their limitations in handling competitive metal ion environments and matrix interference during inductively coupled plasma mass spectrometry (ICP-MS) analysis. The designed prototype aims to overcome these challenges and enhance the extraction efficiency of diverse metals. RESULTS: The FNC, designed to incorporate various functional groups critical for metal ion extraction efficiency, was meticulously engineered through the reaction of acid-treated and delaminated graphitic carbon nitride nanosheets (Thiol-gCN NSs) with 3-mercaptopropyl trimethoxysilane (MPTMS). The competitive metal ion extraction efficiency of FNC@3D PLA was demonstrated, showcasing notable limit of detection values of 3.2 ± 0.7 ng mL-1 and 8.57 ± 3.05 ng mL-1 for Cu and Ag, respectively. Furthermore, the miniaturized 3D-printed metal-preconcentration setup incorporating FNC@3D PLA exhibited favorable intraday relative standard deviation (RSD) percentage (%) values ranging from 1.23 to 8.6 for both Cu and Ag. Interday RSD % between 1.41 and 8.14 were observed under spiked real urine sample conditions. The sustainability and robustness of the proposed approach were underscored by substantial recovery % values exhibited by FNC@3D PLA, even after eight consecutive regeneration processes. SIGNIFICANCE: This study significantly contributes to the advancement of analytical methodologies by providing a reliable and efficient platform for metal extraction and preconcentration in practical metal analysis applications. Developed FNC@3D PLA system demonstrates its potential to address the challenges associated with SPE in metal analysis, especially in complex sample matrices. We believe implications of this research can be extended to various fields, from environmental monitoring to clinical diagnostics, where accurate and reliable metal analysis is paramount.

11.
Analyst ; 138(11): 3271-9, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23612246

RESUMO

In this study, we employed a novel on-line method, push/pull perfusion hollow-fiber liquid-phase microextraction (PPP-HF-LPME), to extract 4-tert-butylphenol, 2,4-di-tert-butylphenol, 4-n-nonylphenol, and 4-n-octylphenol from river and tap water samples; we then separated and quantified the extracted analytes through high-performance liquid chromatography (HPLC). Using this approach, we overcame the problem of fluid loss across the porous HF membrane to the donor phase, permitting on-line coupling of HF-LPME to HPLC. In our PPP-HF-LPME system, we used a push/pull syringe pump as the driving source to perfuse the acceptor phase, while employing a heating mantle and an ultrasonic probe to accelerate mass transfer. We optimized the experimental conditions such as the nature of the HF supported intermediary phase and the acceptor phase, the composition of the donor and acceptor phases, the sample temperature, and the sonication conditions. Our proposed method provided relative standard deviations of 3.1-6.2%, coefficients of determination (r(2)) of 0.9989-0.9998, and limits of detection of 0.03-0.2 ng mL(-1) for the analytes under the optimized conditions. When we applied this method to analyses of river and tap water samples, our results confirmed that this microextraction technique allows reliable monitoring of alkylphenols in water samples.


Assuntos
Microextração em Fase Líquida/métodos , Sistemas On-Line , Fenóis/análise , Fenóis/isolamento & purificação , Água/química , Cromatografia Líquida de Alta Pressão , Microextração em Fase Líquida/instrumentação , Reprodutibilidade dos Testes , Solventes/química , Seringas , Temperatura
12.
Anal Methods ; 15(47): 6531-6540, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37990560

RESUMO

We established an innovative and easy-to-use methodology for selenium (Se) extraction and determination from real water samples utilizing a magnetic nanocomposite adsorbent (MNC-SPE) aided by an inductively coupled plasma mass spectrometry (ICP-MS) approach. The MNC-SPE adsorbent was fabricated by hybridizing Fe3O4 nanoparticles on the surface of carbon nitride nanosheets (GCN NSs) that were coated with 1-hexyl-3-methylimidazolium hexafluorophosphate ionic liquid (P-IL). A variety of techniques were used to thoroughly analyze the structural and chemical characteristics of MNC-SPE, and appear to have a great number of diverse active surface functional units (imidazole ring and -NH3+). In order to optimize the key factors affecting the Se extraction, parameters including the adsorbent dosage, contact time, eluent type, eluent volume, eluent time, and reusability of adsorbent were extensively studied. The proposed approach was validated under the optimal reaction conditions, and it showed good linearity between 0.15 and 100 pg µL-1 with a significant R2 value (R2 = 0.9994) toward Se metal. Besides, the Se limit of detection (LOD) and limit of quantification (LOQ) are 0.063 pg µL-1 and 0.147 pg µL-1, respectively. Further, by utilizing tap and river water samples, the applicability of the validated method was tested; the approach showed high Se recovery values in the range of 87.6-115.5% for the spiked real-world samples and the interday and intraday precision (RSD%) values of the approach were 4.8% (n = 6). The MNC-SPE can be regenerated and reused for four consecutive extraction-desorption cycles by employing 0.5 M NaOH eluent.

13.
Toxicol Appl Pharmacol ; 259(2): 177-86, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22245127

RESUMO

Nickel compounds are known to be toxic and carcinogenic in kidney and lung. In this present study, we investigated the roles of reactive oxygen species (ROS) and mitochondria in nickel (II) acetate-induced cytotoxicity and apoptosis in the HK-2 human renal cell line. The results showed that the cytotoxic effects of nickel (II) involved significant cell death and DNA damage. Nickel (II) increased the generation of ROS and induced a noticeable reduction of mitochondrial membrane potential (MMP). Analysis of the sub-G1 phase showed a significant increase in apoptosis in HK-2 cells after nickel (II) treatment. Pretreatment with N-acetylcysteine (NAC) not only inhibited nickel (II)-induced cell death and DNA damage, but also significantly prevented nickel (II)-induced loss of MMP and apoptosis. Cell apoptosis triggered by nickel (II) was characterized by the reduced protein expression of Bcl-2 and Bcl-xL and the induced the protein expression of Bad, Bcl-Xs, Bax, cytochrome c and caspases 9, 3 and 6. The regulation of the expression of Bcl-2-family proteins, the release of cytochrome c and the activation of caspases 9, 3 and 6 were inhibited in the presence of NAC. These results suggest that nickel (II) induces cytotoxicity and apoptosis in HK-2 cells via ROS generation and that the mitochondria-mediated apoptotic signaling pathway may be involved in the positive regulation of nickel (II)-induced renal cytotoxicity.


Assuntos
Acetatos/toxicidade , Apoptose/efeitos dos fármacos , Túbulos Renais Proximais/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Acetatos/antagonistas & inibidores , Acetilcisteína/farmacologia , Apoptose/fisiologia , Caspases/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Citometria de Fluxo , Humanos , Túbulos Renais Proximais/metabolismo , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias/metabolismo , Compostos Organometálicos/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
14.
Toxicol Appl Pharmacol ; 262(3): 232-7, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22569360

RESUMO

Arsenic ingestion has been linked to increasing global prevalence of and mortality from cardiovascular disease (CVD); arsenic can be removed from drinking water to reduce related health effects. Lactate dehydrogenase (LDH) is used for the evaluation of acute arsenic toxicity in vivo and in vitro, but it is not validated for the evaluation of long-term, chronic arsenic exposure. The present study examined the long-term effect of chronic arsenic exposure on CVD and serum LDH levels, after consideration of arsenic metabolism capacity. A total of 380 subjects from an arseniasis-endemic area and 303 from a non-endemic area of southwestern Taiwan were recruited in 2002. Various urinary arsenic species were analyzed using high-performance liquid chromatography (HPLC) and hydride generation systems. Fasting serum was used for quantitative determination of the total LDH activity. A significant dose-response relationship was observed between arsenic exposure and LDH elevation, independent of urinary arsenic profiles (P<0.001). Furthermore, abnormal LDH elevation was associated with CVD mortality after adjustment for Framingham risk scores for 10-year CVD and arsenic exposure (hazard ratio, 3.98; 95% confidence interval, 1.07-14.81). LDH was elevated in subjects with arsenic exposure in a dose-dependent manner. LDH is a marker of arsenic toxicity associated with CVD mortality. Results of this study have important implications for use in ascertaining long-term arsenic exposure risk of CVD.


Assuntos
Arsênio/efeitos adversos , Doenças Cardiovasculares/mortalidade , Exposição Ambiental/efeitos adversos , L-Lactato Desidrogenase/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Arsênio/urina , Doenças Cardiovasculares/induzido quimicamente , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan/epidemiologia
15.
Anal Chim Acta ; 1231: 340418, 2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36220291

RESUMO

This study reports a facile approach for the fabrication of chitosan (CS, biopolymer)- and l-histidine (L-His, biomolecule)-stabilized self-assembled silicon nanoparticles (SiNPs) for sensing Cu2+ ions. Approached method yielded 3.8 ± 0.04 nm size CS/L-His-SiNPs particles, with high stability against harsh pH and temperature conditions. Besides, CS/L-His-SiNPs highly selective to Copper amongst different metal ions tested (Fe3+, Mg2+, Al3+, Cr3+, Cr6+, Cu2+, Mn2+, Cd2+, Pb2+, Zn2+, Hg2+, Ca2+, Li2+, Po42-, As3+, As5+). As compared to the blank-SiNPs (LOD = 96.49 ± 0.223 µM) and CS-SiNPs (LOD = 33.35 ± 1.004 µM); L-His ligand, enhanced the sensitivity of the CS/L-His-SiNPs toward Cu2+ with remarkable LOD value of 55.02 ± 0.42 nM. Applicability of CS/L-His-SiNPs was evaluated by coating CS/L-His-SiNPs on thin layer chromatography (TLC) sheets, CS/L-His-SiNPs-TLC sheets exhibited significant sensing capacity toward Cu2+ ions, with a detection range of 4.0-900 µM, making them suitable for on-site analysis of Cu2+ ions from both environmental and clinical samples. Finally, Cu2+ sensing practicality of CS/L-His-SiNPs-TLC sheets were challenged against real human urine samples. Expressively, CS/L-His-SiNPs-TLC sheets could be regenerated using ethylenediaminetetraacetic acid (EDTA), without losing their photostability, and can be reused further.


Assuntos
Quitosana , Mercúrio , Nanopartículas , Cádmio , Cromatografia em Camada Fina , Cobre/química , Ácido Edético/química , Histidina , Humanos , Íons , Chumbo , Ligantes , Nanopartículas/química , Silício
16.
Bioresour Technol ; 351: 127018, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35307519

RESUMO

Current study aims to synthesize chitosan/polyvinyl alcohol (CS/PVA), poly(ethyleneimine), and Fe3O4 impregnated beads for co-removal of Cr(VI) and toxic azo-dyes from wastewater. The mesoporous PEI@AC@Fe3O4 exhibits magnetism and enhanced physisorption by higher specific-porosity (2.1 nm) from Cr(VI) radii (0.044 nm). Moreover, surface functional groups (-OH, -NH, -NH2, -COOH etc.), especially amines enhance ionic bonding due to positive zeta potential. Hence, it is unique for anionic dyes removal under a wide pH range. It showed maximum adsorption capacity 98, 85.5, 85.8, and 91%, or 199.8, 148, 167, 176.5 mg g-1 respectively for Cr(VI), tartrazine, sunset yellow, and erythrosine. Surface adsorption of Cr(VI) and its transition into Cr(III) was confirmed by EDX. Langmuir isotherm and pseudo-first-order kinetics best fit the adsorption of Cr(VI) and azo-dyes confirming their monolayer physisorption on adsorbent surface. Synthesized adsorbent examined in wastewater purification prototype for efficient removal of different simulated wastewaters confirms its potential for real-world applications.


Assuntos
Quitosana , Corantes de Alimentos , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Cromo/análise , Corantes , Concentração de Íons de Hidrogênio , Cinética , Águas Residuárias , Poluentes Químicos da Água/análise
17.
Biol Trace Elem Res ; 200(7): 3060-3069, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34581971

RESUMO

Several hormones and elements are involved in the homeostasis of glucose metabolism during pregnancy. This present study determined the differences among the factors involved in glucose regulation for pregnant women with and without an abnormal glucose challenge test (GCT), but without gestational diabetes mellitus, during the second trimester of gestation and the postpartum period. One hundred and six pregnant women who had received routine prenatal and postpartum examinations at our hospital were recruited. Sugar-related tests and the levels of pregnancy-associated hormones and 25-OH-vitamin D were performed using a clinical autoanalyzer; six elements were assessed using graphite furnace atomic absorption spectrometry or inductively coupled plasma mass spectrometry. The women in the abnormal GCT group (n = 27) featured significantly higher levels of 25-OH-vitamin D (p = 0.006) and copper (p < 0.001) than those in the normal GCT group (n = 79). After adjusting for possible pregnancy factors, abnormal GCT remained the significant contributing factor for the elevated levels of 25-OH-vitamin D and copper during gestation (p = 0.046 and 0.002, respectively). Furthermore, significant positive correlations existed between 25-OH-vitamin D and glucose after a 50-g GCT (p = 0.001), 25-OH-vitamin D and HbA1C (p = 0.004), serum copper and glucose after a 50-g GCT (p = 0.003), and serum copper and HbA1C (p < 0.001). We conclude that blood 25-OH-vitamin D and copper are strongly correlated with glucose levels during gestation; these two factors are potential clinical predictors for maternal impaired glucose tolerance and, indirectly, for reducing perinatal risks and neonatal complications.


Assuntos
Diabetes Gestacional , Vitamina D , Glicemia/metabolismo , Cobre , Feminino , Teste de Tolerância a Glucose , Hormônios , Humanos , Recém-Nascido , Gravidez , Gestantes , Vitaminas
18.
J Microbiol Immunol Infect ; 54(6): 1122-1129, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34244117

RESUMO

BACKGROUND: The emergence of carbapenem-non-susceptible Enterobacteriaceae (CnSE) infections is a public health threat. This study investigated the risk factors and clinical impact of bacteremia due to CnSE. MATERIAL AND METHODS: The study was conducted at three hospitals in southern Taiwan between January 1, 2017, and October 31, 2019. Only the first episode of CnSE bacteremia from each adult was included. For one episode of CnSE bacteremia, two subsequent bacteremic episodes due to carbapenem-susceptible Enterobacteriaceae isolates in each hospital were included as the controls. RESULTS: Among a total of 641 episodes of monomicrobial Enterobacteriaceae bacteremia were noted, 47 (7.3%) of which were of CnSE bacteremia. Ninety-four episodes of carbapenem-susceptible Enterobacteriaceae (CSE) bacteremia were selected as the controls for further analyses. In the multivariate analysis, hypertension (odds ratio [OR], 4.21; P = 0.005), Pitt bacteremia score (OR, 1.61; P = 0.002), and nosocomial bacteremia (OR, 3.30; P = 0.01) were associated with carbapenem nonsusceptibility among Enterobacteriaceae bacteremia. The most abundant CnSE isolate was Klebsiella pneumoniae (91.5%), followed by Klebsiella oxytoca (6.4%) and Escherichia coli (2.1%). Patients with CnSE bacteremia had a higher overall in-hospital mortality rate than those with CSE bacteremia (53.2% vs. 23.4%, P = 0.001). Moreover, in the multivariate analysis, the in-hospital mortality was significantly associated with higher Pitt bacteremia score (OR, 1.38; P = 0.02) and marginally associated with CnSE infections (OR, 2.44; P = 0.06). CONCLUSION: Among adults with Enterobacteriaceae bacteremia, carbapenem nonsusceptibility, male sex, and the presence of hypertension or chronic kidney disease indicate a poor prognosis during hospitalization.


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Carbapenêmicos/farmacologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/epidemiologia , Enterobacteriaceae/classificação , Infecções por Enterobacteriaceae/epidemiologia , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Masculino , Testes de Sensibilidade Microbiana , Razão de Chances , Fatores de Risco , Taiwan/epidemiologia
19.
Infect Drug Resist ; 14: 689-697, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658807

RESUMO

BACKGROUND: Reducing the effectiveness of broad-spectrum cephalosporins against Enterobacteriaceae infections has been recognized. This study aimed to investigate risk factors and clinical significance of third-generation cephalosporin nonsusceptibility (3GC-NS) among the cases of monomicrobial Enterobacteriaceae bacteremia (mEB) at regional or district hospitals. METHODS: The study was conducted at three hospitals in southern Taiwan between Jan. 2017 and Oct. 2019. Only the first episode of mEB from each adult (aged ≥20 years) was included. The primary outcome was in-hospital crude mortality. RESULTS: Overall there were 499 episodes of adults with mEB included, and their mean age was 74.5 years. Female predominated, accounting for 53% of all patients. Escherichia coli (62%) and Klebsiella pneumoniae (21%) were two major causative species. The overall mortality rate was 15% (73/499), and patients infected by 3GC-NS isolates (34%, 172/499) had a higher mortality rate than those by 3GC-susceptible isolates (66%, 327/499) (21% vs 11%, P=0.005). By the multivariate analysis, 3GC-NS was the only independent prognostic determinant (adjusted odds ratio [AOR], 1.78; P=0.04). Of note, male (AOR 2.02, P=0.001), nosocomial-acquired bacteremia (AOR 2.77, P<0.001), and usage of nasogastric tube (AOR 2.01, P=0.002) were positively associated with 3GC-NS, but P. mirabilis bacteremia (AOR 0.28, P=0.01) and age (AOR 0.98, P=0.04) negatively with 3GC-NS. CONCLUSION: For adults with Enterobacteriaceae bacteremia, 3GC-NS signifies a significant prognostic impact. Efforts to rapid identification of such antimicrobial resistance profiles should be incorporated into antimicrobial stewardship programs to achieve favorable outcomes.

20.
Environ Pollut ; 266(Pt 2): 115204, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32745991

RESUMO

A major health scandal involving DEHP-tainted (di-2-ethylhexyl phthalate) foodstuffs occurred in Taiwan in 2011. We investigated temporal relationships between urinary DEHP metabolites and biomarkers of oxidative stress in two cohorts of potentially affected children during that food scandal. One cohort was collected from Kaohsiung Medical University Hospital in southern Taiwan between May and June of 2011 (the KMUH cohort). This cohort was followed up at 2, 6, and 44 months. The other cohort was collected from a nationwide health survey conducted by Taiwan's National Health Research Institutes (the NHRI cohort) for potentially affected people between August 2012 and January 2013. Both cohorts only included children 10 years old and younger who had provided enough urine for analysis of urinary DEHP oxidative metabolites and two markers of oxidative stress: 8-oxo-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA). The KMUH cohort had a simultaneous and significant decrease in urinary DEHP metabolites, 8-OHdG, and MDA, with the lowest concentrations found at the 6-month follow up and maintained until the 44-month follow up, consistent with those from NHRI cohort at ∼15-18 months post-scandal (p > 0.05). There were decreases in both DEHP metabolites and oxidative stress markers across the populations, but no association was observed between DEHP metabolites and oxidative stress markers in individuals in the two cohorts. Continued follow-up is needed to determine long-term health consequences in these children.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Biomarcadores , Criança , Seguimentos , Humanos , Estresse Oxidativo , Taiwan
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