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1.
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
2.
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.

3.
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
4.
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
5.
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
6.
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
7.
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
8.
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.

9.
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.

10.
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
11.
Am J Trop Med Hyg ; 101(4): 899-904, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31392948

RESUMO

Universal immunoprophylaxis against hepatitis B virus (HBV) is regarded as a key element to prevent perinatal HBV infection. The aim of the present study was to investigate the changes in the hepatitis B surface antigen (HBsAg)- and hepatitis B envelope antigen (HBeAg)-positive rates in native and immigrant pregnant women, to realize the impact of immigrants, and to identify any weaknesses 30 years after the implementation of hepatitis B vaccination in Taiwan. A total of 20,020 test results of HBsAg and HBeAg in pregnant women-2,915 (14.6%) immigrant women and 17,105 native Taiwanese-from 1996 to 2015 were analyzed for changes during this 20-year retrospective cohort study. Native Taiwanese have a higher HBsAg-positive rate than immigrant women (P < 0.001). However, the HBsAg-positive rates decreased by 0.6% per year among native women, but did not decrease significantly (only by 0.18% per year) among immigrant women. The overall HBsAg-positive rate remained at high levels, 4.8% in the year 2015. The HBeAg-positive rate decreased significantly, by 0.22% per year, in the total women as well as by 0.23% per year in the native women (all P < 0.001); by contrast, the HBeAg-positive rate in immigrants decreased at a slower rate (0.10% per year), without a significant decreasing trend (P = 0.300). Higher HBeAg (+)/HBsAg (+) rate was found for the immigrants than for the native women (P < 0.001). To quickly and effectively lower the risk of vertical transmission, new approaches combined with vaccination may be needed in the post-immunization era.


Assuntos
Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Vacinação , Adolescente , Adulto , Emigrantes e Imigrantes , Feminino , Hepatite B/prevenção & controle , Hepatite B/virologia , Humanos , Programas de Imunização , Pessoa de Meia-Idade , Grupos Populacionais , Gravidez , Estudos Retrospectivos , Estudos Soroepidemiológicos , Taiwan/epidemiologia , Adulto Jovem
12.
J Food Drug Anal ; 27(2): 439-450, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987715

RESUMO

In this study the recently developed technique of thermal desorption electrospray ionization/mass spectrometry (TD-ESI/MS) was applied to the rapid analysis of multiple controlled substances. With the reallocation of mass spectral resources [from a standard ESI source coupled with liquid chromatography (LC) to an ambient TD-ESI source], this direct-analysis technique allows the identification of a wider range of illicit drugs through a dual-working mode (pretreatment-free qualitative screening/conventional quantitative confirmation). Through 60-MRM (multiple reaction monitoring) analysis-in which the MS/MS process was programmed to sequentially scan 60 precursor ion/product ion transitions and, thereby, identify 30 compounds (two precursor/product ion transitions per compound)-of a four-component (drug) standard, the signal intensity ratios of each drug transition were comparable with those obtained through 8-MRM analysis, demonstrating the selectivity of TD-ESI/MS for the detection of multiple drugs. The consecutive analyses of tablets containing different active components occurred with no cross-contamination or interference from sample to sample, demonstrating the reliability of the TD-ESI/MS technique for rapid sampling (two samples min-1). The active ingredients in seized drug materials could be detected even when they represented less than 2 mg g-1 of the total sample weight, demonstrating the sensitivity of TD-ESI/MS. Combining the ability to rapidly identify multiple drugs with the "plug-and-play" design of the interchangeable ion source, TD-ESI/MS has great potential for use as a pretreatment-free qualitative screening tool for laboratories currently using LC-MS/MS techniques to analyze illicit drugs.


Assuntos
Contaminação de Alimentos/análise , Drogas Ilícitas/análise , Cromatografia Líquida , Contaminação de Medicamentos , Humanos , Espectrometria de Massas
13.
Kaohsiung J Med Sci ; 34(7): 409-414, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30063014

RESUMO

The measurement of serum osmolality, and the calculation of osmolal gap (OG) from a calculated osmolality are widely used in clinical and emergency medicine. In this study, the possible effects of blood glucose on OG were investigated by freezing point depression and vapor pressure methods. The concentrations of sodium, glucose, blood urea nitrogen and osmolalities of 2640 samples were measured. There were two methods for calculating serum osmolality: freezing point depression method (n = 2399) and vapor pressure method (n = 241). The OG was positively associated with glucose in glucose 110-450 mg/dL (r = 0.191, p < 0.001) and glucose > 450 mg/dL (r = 0.372, p < 0.001), but not in glucose < 110 mg/dL (r = 0.017, p = 0.711) in freezing point depression method. However, OG had no correlation with glucose regardless of glucose level in vapor pressure method. In freezing point depression method, compared with the groups of glucose <110 and 110-450 mg/dL, the group with glucose >450 mg/dL had higher OG (p < 0.001) and higher prevalence of OG > 10 mOsm/Kg H2O (p < 0.001). Our study demonstrated that OG is impacted by increasing blood glucose concentration using freezing point depression method, special attention should be made to blood glucose concentrations when using freezing point depression method to determine OG.


Assuntos
Glicemia/metabolismo , Congelamento , Concentração Osmolar , Pressão de Vapor
14.
J Trace Elem Med Biol ; 48: 1-7, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29773167

RESUMO

Chromium poisoning can cause renal failure and death. Chromium intoxication may be managed using L-ascorbic acid (vitamin C) therapy. However, the evidence supporting the effectiveness of this treatment is insufficient, and the mechanism of action has not been clarified in renal cells. In this study, our results showed that the optimal regimen of L-ascorbic acid therapy in human epithelial renal proximal tubule cells, HK-2 cells, was 30 µg/mL. Supplementation of L-ascorbic acid with 30 µg/mL and within 8 h of chromium intoxication (K2Cr2O7, Cr6+) was effective to inhibit renal tubular cell damage by blocking generation of free radicals, cell apoptosis, and autophagy. Intracellular chromium concentrations were estimated using electrothermal atomic absorption spectrometry. Treatment of L-ascorbic acid within 8 h of chromium intoxication significantly decreased the entry of chromium into the cells. Moreover, concomitant administration of L-ascorbic acid with repeatedly dosing at 8-hourly intervals had a better protective effect at lower concentration of L-ascorbic acid when compared to single dosing of L-ascorbic acid at an early time point of chromium intoxication. These findings might help physicians develop effective therapy strategies in renal failure.


Assuntos
Ácido Ascórbico/farmacologia , Intervenção Educacional Precoce , Túbulos Renais/efeitos dos fármacos , Dicromato de Potássio/antagonistas & inibidores , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Túbulos Renais/patologia , Estresse Oxidativo/efeitos dos fármacos , Dicromato de Potássio/efeitos adversos
15.
Biol Trace Elem Res ; 186(2): 330-336, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29589268

RESUMO

Trace elements can influence glucose metabolism and be related to oxidative stress in type 2 diabetes mellitus. Moreover, trace elements play important roles in the nephrotic complications of these patients. Nevertheless, few investigations have been made into the changes in the levels of trace elements in diabetic patients at various stages of chronic kidney disease (CKD). The aims of this present study were to determine the levels of some important trace elements in diabetic patients during the early stages of CKD and to identify the relationship between these elements and CKD progression in type 2 diabetic patients. One hundred and forty-eight type 2 diabetic patients with chronic kidney diseases were recruited into this study. The subjects were grouped into four stages (1, 2, 3a, 3b) of CKD, according to their urine protein levels and estimated glomerular filtration rates (eGFRs). The levels of serum zinc and iron exhibited a statistically significant decreasing trend (P trend = 0.032 and 0.047, respectively) from stage 1 to stage 3b after adjustment for age, gender, smoking, alcohol consumption, education, hypertension, and body mass index. The other tested elements, including copper, magnesium, selenium, chromium, and manganese, did not display any significant trends upon proceeding from stage 1 to stage 3b. Thus, serum zinc and iron appear to be useful markers when evaluating the early progression of CKD in type 2 diabetic patients.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Insuficiência Renal Crônica/sangue , Oligoelementos/sangue , Idoso , Diabetes Mellitus Tipo 2/complicações , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Humanos , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Proteinúria/urina , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/patologia , Índice de Gravidade de Doença , Zinco/sangue
16.
Oncotarget ; 9(9): 8738-8745, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29492233

RESUMO

Hyperuricemia has been associated with low heart rate variability (HRV), however whether there is an association between uric acid (UA) and HRV changes after hemodialysis (HD) is unknown. The aim of this study was to investigate the role of UA in HRV changes before and after HD in non-diabetic patients. Ninety-six non-diabetic patients under maintenance HD were enrolled. HRV was examined to assess changes before and after HD. A change in HRV (ΔHRV) was calculated as post-HD HRV minus pre-HD HRV. Compared to the patients with a UA level ≦ 7 mg/dL, those with a UA level > 7 mg/dL had lower ∆high frequency (HF)% (p = 0.027). UA was negatively associated with ∆HF% (r = -0.247, p = 0.015) and ∆low frequency (LF)/HF (r = -0.236, p = 0.021) in the non-diabetic patients undergoing HD. Furthermore, in multivariate analysis after adjustments for demographic, clinical, and biochemical characteristics and medications, UA was independently associated with ∆HF% (per 1 mg/dL, unstandardized coefficient ß = -2.892; 95% CI, -5.066 to -0.717; p = 0.010) and ∆LF/HF (per 1 mg/dL, unstandardized coefficient ß = -0.165; 95% CI, -0.291 to -0.038; p = 0.011). Hyperuricemia contributed to lesser HF% and LF/HF increase after HD in the non-diabetic patients, reflecting a state of impaired sympatho-vagal equilibrium in non-diabetic HD patients with hyperuricemia. Lowering UA levels may have the potential to improve increased HRV in non-diabetic HD patients.

17.
Food Chem ; 252: 189-197, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29478531

RESUMO

Ambient mass spectrometry using an interchangeable thermal desorption/electrospray ionization source (TD-ESI) is a relatively new technique that has had only a limited number of applications to date. Nevertheless, this direct-analysis technique has potential for wider use in analytical chemistry (e.g., in the rapid direct detection of contaminants, residues, and adulterants on and in food) when operated in dual-working mode (pretreatment-free qualitative screening and conventional quantitative confirmation) after switching to a TD-ESI source from a conventional ESI source. Herein, we describe the benefits and challenges associated with the use of a TD-ESI source to detect adulterants on traditional Chinese pastries (TCPs), as a proof-of-concept for the detection of illegal colorants. While TD-ESI can offer direct (i.e., without any sample preparation) qualitative screening analyses for TCPs with adequate sensitivity within 30 s, the use of TD-ESI for semi-quantification is applicable only for homogeneous matrices (e.g., tang yuan).


Assuntos
Corantes de Alimentos/análise , Contaminação de Alimentos/análise , Contaminação de Alimentos/legislação & jurisprudência , Espectrometria de Massas por Ionização por Electrospray/métodos , Temperatura , Análise de Alimentos , Qualidade dos Alimentos , Fatores de Tempo
18.
Anal Chim Acta ; 1010: 44-53, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29447670

RESUMO

Thermal desorption electrospray ionization/mass spectrometry (TD-ESI-MS) employing a quickly interchangeable ionization source is a relatively new ambient ionization mass spectrometric technique that has had, to date, only a limited number of applications related to food safety control. With reallocation of resources, this direct-analysis technique has had wider use in food analysis when operated in dual-working mode (pretreatment-free qualitative screening and conventional quantitative confirmation) after switching to an ambient ionization source from a traditional atmospheric pressure ionization source. Herein, we describe the benefits and challenges associated with the use of a TD-ESI source to detect adulterants in processed vegetables (PVs), as a proof-of-concept for the detection of basic colorants. While TD-ESI can offer direct qualitative screening analyses for PVs with detection capabilities lower than those provided with liquid chromatography/UV detection within 30 s, the use of TD-ESI for semi-quantification is applicable only for homogeneous food matrices.


Assuntos
Análise de Alimentos , Corantes de Alimentos/análise , Contaminação de Alimentos/análise , Temperatura , Verduras/química , Espectrometria de Massas por Ionização por Electrospray
19.
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
20.
Oncotarget ; 8(55): 94407-94416, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29212237

RESUMO

The association between DM and left ventricular diastolic dysfunction, assessed using the ratio of peak early transmitral filling wave velocity (E) to early diastolic velocity of mitral annulus (Ea), with cardiovascular (CV) outcomes in patients with chronic kidney disease (CKD) remains uncertain. This study included 356 CKD stage 3-5 patients underwent echocardiography. All patients were classified into four groups based on the presence of DM and E/Ea ≤ or > 9. CV events included CV death, hospitalization for heart failure, unstable angina or nonfatal myocardial infarction, sustained ventricular arrhythmia, transient ischemic attack, and stroke. There were 58 CV events during the mean observation period of 25.0 months. A combination of the presence of DM and E/Ea > 9 (vs. a combination of non-DM and E/Ea ≤ 9) was associated with CV events in unadjusted model (hazard ratio [HR], 6.990; 95% confidence interval [CI], 2.753-17.744; p < 0.001), and in a multivariate adjusted model (HR, 3.037; 95% CI, 2.088-7.177; p = 0.025). In the patients without DM, the E/Ea ratio (p = 0.033) improved the prediction of CV events, compared to the E/Ea ratio (p = 0.018), left atrial diameter (p = 0.016) and left ventricular mass index (p = 0.001) in the patients with DM. The combination of DM and left ventricular diastolic dysfunction was associated with CV events in patients with CKD stage 3-5. Assessments of DM status and E/Ea ratio may facilitate identifying high-risk patient population of unfavorable CV outcomes.

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