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1.
Am J Reprod Immunol ; : e13261, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32356306

RESUMO

PROBLEM: The state of self-renewal and self-maintain of decidual macrophages would be important for immune homeostasis at the maternal-fetal interface. The roles of interleukin (IL)-24 derived from decidual stromal cells (DSCs) on decidual macrophages have not been explored. METHOD OF STUDY: IL-24 expression in DSCs was interfered by lentivirus and the transcription levels of IL24 in DSCs were verified by Real Time (RT)-PCR. The levels of IL-24 receptors were determined by flow cytometry assays. The effect of recombination human IL-24 (rhIL-24) on the differentiation and apoptosis of macrophages was analyzed by flow cytometry in vitro. The viability of macrophages was detected by Cell Counting Kit-8 assays. RESULTS: The growth of DSCs was not affected obviously only by IL-24 knockdown while the growth of knockdown DSCs was inhibited significantly after co-cultured with decidual macrophages. The levels of IL-24 receptors (IL-20R1 and IL-22R1) was medium to high expressed on decidual macrophages and human macrophage cell line U937. The differentiation of decidual macrophages treated by rhIL-24 or co-cultured with IL-24 knockdown DSCs was not affected. Both apoptosis and viability of U937 cells were promoted by rhIL-24. The ratio of Bcl-2/Bax was down-regulated and Ki-67 was up-regulated by IL-24 treatment. The expression of Bcl-2/Bax was up-regulated while Ki-67 was down-regulated in U937 cells after co-cultured by IL-24 knockdown DSCs. CONCLUSIONS: IL-24 secreted by DSCs promotes the renewal and homeostasis of decidual macrophages possibly via downregulating the ratio of Bcl-2/Bax and upregulating of the expression of Ki-67 in early pregnancy.

2.
J Chromatogr Sci ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32390045

RESUMO

A simple and rapid pipette-tip solid-phase extraction (PT-SPE) procedure with derivatization prior to gas chromatography triple quadrupole mass spectrometry analysis is developed for the simultaneous determination of amphetamine (AMP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) in urine samples. The PT-SPE procedure using self-made sorbent could extract drugs within 6 min from 100-µL urine samples, requiring low solvent-consumption (<2.0 mL). Besides, the self-made pipette tip could be reused at least five times. Under optimized conditions, the recoveries of four amphetamines at spiked levels (low, medium and high) ranged from 87.7 to 110.4%, with relative standard deviations < 9.5%. The limit of detections and limit of quantifications for AMP, MA, MDA and MDMA were in the range of 2.52-8.25 ng⋅mL-1 and 8.4-27.5 ng⋅mL-1, respectively. Validation results show that the proposed method is suitable for the quantitation of amphetamines and has been successfully applied in the urine samples of suspected drug abusers.

3.
Clin Lab ; 66(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32390382

RESUMO

BACKGROUND: There is increasing evidence that matrix metalloproteinase 14 (MMP-14) is involved in tumor progression and prognosis. MMP-14 exhibits different expression in patients with various cancers, suggesting that it may be considered as a potential prognostic biomarker for cancer. METHODS: Therefore, this meta-analysis was performed to elucidate the prognostic value and association of MMP-14 over-expression in several types of cancers. Eligible studies based on eligibility criteria from various online databases were searched. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) for overall survival (OS) were analyzed to determine the prognostic value of MMP-14 using STATA software 12.0. RESULTS: We identified sixteen applicable studies in this meta-analysis comprising 2,766 samples. Over-expression MMP-14 was significantly correlated with a poor overall survival (OS) outcome in multiple cancers (HR: 2.22; 95% CI: 1.72 - 2.87). Moreover, high levels of MMP-14 were markedly associated with tumor progression and metastasis (HR: 1.83; 95% CI: 1.36 - 2.46). MMP-14 expression was also associated with histological differentiation (OR: 0.37; 95% CI: 0.18 - 0.77). CONCLUSIONS: MMP-14 over-expression suggested aggressive biological behaviors and implied that MMP-14 may be a useful prognostic biomarker in human cancers.

4.
Ultrasound Med Biol ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32404297

RESUMO

This study aims to evaluate the difference in renal parenchyma stiffness assessed by measuring Young's modulus (YM) using a supersonic shear wave imaging (SSI) technique among healthy patients and patients with type 2 diabetes mellitus (DM) with and without diabetic kidney disease (DKD). We analyzed the correlations of YM with clinical information and conventional ultrasound parameters. All patients (N ==) were divided into three groups: (i) healthy patients (patients without kidney disease or type 2 DM, N = 31); (ii) patients with type 2 DM without kidney disease (N = 38); and (iii) patients with DKD (N = 55). Conventional and SSI ultrasound examinations were performed in all individuals for both kidneys. Then, we recorded renal length, width, parenchyma thickness, interlobar arterial resistive index (RI) and values of mean, mininum and maximum YM. The mean values of these parameters for the left and right kidneys were calculated for statistical analysis. Statistical significance was considered at p < 0.05. Among all ultrasound parameters, the mean YM demonstrated the largest area under the receiver operating characteristic (ROC) curve (0.860). The areas under the ROC curve (AUCs) for renal length, width, parenchyma thickness, interlobar arterial RI, minimum YM and maximum YM were 0.493, 0.616, 0.507, 0.733, 0.848 and 0.794, respectively. The corresponding cutoff value of mean YM was 31.73 kPa, with a sensitivity of 85.5% and a specificity of 71.0%. The mean YM in patients with type 2 DM without kidney disease (31.44 ± 3.83 kPa) was significantly higher than that in the healthy group (26.45 ± 4.32 kPa) and lower than that in the DKD group (37.60 ± 6.56 kPa). Patients with type 2 DM without kidney disease were considered as stage 0 of DKD. Thus, the mean YM in the control group was significantly lower than that in the stage 0, 2, 3, 4 and 5 subgroups. The mean YM in the stage 0-2 subgroups was lower than that in the stage 5 group, and the mean YM in the stage 0 group was lower than that in the stage 4 group. In the DKD group, the mean YM had a positive correlation with cystine-c (r = 0.634), urea (r = 0.596), creatine (r = 0.690), uric acid (r = 0.263), albumin/creatinine ratio (r = 0.428) and the presence or absence of diabetic retinopathy (r = 0.354). The mean YM also had a negative correlation with the estimated glomerular filtration rate (r = -0.657). SSI is a non-invasive method with which to diagnose DKD and has a performance superior to that of conventional ultrasound. In addition, SSI may provide a secondary index for the staging of DKD and the monitoring of renal damage in type 2 DM patients.

5.
J Agric Food Chem ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32407080

RESUMO

Se-enriched green tea, with an increasing consumption, is the shoot of tea plants which grown naturally in a seleniferous region. A label-free proteomic strategy based on UHPLC-Q-Orbitrap was applied to characterize and distinguish the difference between the Se-enriched and normal green tea with a total of 283 proteins identified and 264 proteins quantified in which 96 proteins were observed difference. The expressions of 10 proteins were up-regulated and 40 proteins were down-regulated (P < 0.05) in Se-enriched samples. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes pathway and Protein-protein interaction network analysis results indicated that these differentially expressed proteins significantly interacted and involved in secondary metabolites and inflammatory response biological processes. Furthermore, the expression of Me-JA and ethylene related genes changed significantly in Se-enriched green tea and catalase proteins were employed as center of the pathway that changed significantly in PPI network. These results associating with current knowledge of selenium in soil-plant cycling revealed the organic selenium was synthesized in green tea, which provided novel information of the Se-assimilation in Camellia sinensis and improved the understanding of Se-enriched green tea as a possible ideal selenium supplement in daily life.

6.
Microb Drug Resist ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32407190

RESUMO

We investigated the antibiotic-resistance phenotypes and molecularly characterized class 1 integron gene cassettes from 113 Pseudomonas aeruginosa isolates from patients. Primers specific for the class 1 integron integrase (intI1) gene were used to screen for these integrons using polymerase chain reactions (PCRs). The variable regions of the integrons were PCR-amplified and sequenced. Sputum was the most common specimen (69.9%; 79/113) followed by aseptic sites (21.2%; 24/113). Of the 113 isolates with phenotypic resistance to the tested antimicrobials, the highest resistances were to ciprofloxacin (CIP) (26.55%), imipenem (IPM) (23.89%), and meropenem (MEM) (23%). Carbapenem-sensitive P. aeruginosa (CS-PA) isolates displayed 23 patterns, and the predominant multidrug resistance phenotype was CIP-levofloxacin (7.23%, 6/83). Carbapenem-resistant P. aeruginosa (CR-PA) isolates displayed 12 patterns, and the predominant multidrug resistance phenotype was IPM-MEM (23.33%, 7/30). Class 1 integrons were detected in 14 (12.4%, 14/113) isolates, 7.22% (6/83) in CS-PA isolates, and 26.67% (8/30) in CR-PA isolates. Six gene cassette arrays were detected, the most prevalent being aacA4-blaOXA101-aadA5 in five isolates (4.4%, 5/113). Seventeen gene cassettes were detected. The most prevalent antibiotic-resistance gene cassettes were aacA4 (6.2%, 7/113), blaOXA-1, and blaOXA-101. Extended-spectrum ß-lactamase resistance genes were detected. Some of the genes carried were similar to those in other species, but some had shared characteristics among the P. aeruginosa isolates. Long-standing drug resistance genes appeared to be under elimination in P. aeruginosa, whereas integrons conferring resistance to commonly used clinical drugs such as ß-lactamases, fluoroquinolones, and even carbapenems, as well as some other gene elements, were found to be newly integrated.

7.
Sci Total Environ ; 729: 139031, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32387777

RESUMO

Two important strobilurin fungicides, kresoxim-methyl and pyraclostrobin, are widely used globally. Their effects on embryonic development and oxidative stress effects in the larvae and adult fish livers of zebrafish (Danio rerio) were assessed in our study. The hatching, mortality, and teratogenic rates were determined when the eggs of fish were exposed to kresoxim-methyl and pyraclostrobin for 24-144 h postfertilization (hpf). For further study, the effects of kresoxim-methyl and pyraclostrobin on antioxidant enzymes [catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD)], detoxification enzymes [carboxylesterase (CarE) and glutathione S-transferase (GST)] and the malondialdehyde (MDA) content of larval zebrafish (96 h) and male or female adult zebrafish livers (up to 28 d) were evaluated for potential toxicity mechanisms. The study of embryonic development revealed that both kresoxim-methyl and pyraclostrobin caused developmental toxicity (hatching inhibition, mortality, and teratogenic rates) increase with significant concentration- and time-dependent responses, and the 144-h median lethal values (LC50) of kresoxim-methyl and pyraclostrobin were 195.0 and 81.3 µg L-1, respectively. In the larval zebrafish study, both kresoxim-methyl and pyraclostrobin at the highest concentrations (100 µg L-1 and 15 µg L-1, respectively) significantly increased the CAT, POD and CarE activities and MDA content compared with those of the control group (P < 0.05). We further found that oxidative stress effects in adult zebrafish livers caused by long-term kresoxim-methyl and pyraclostrobin exposure differed with time and sex. Regarding the residues in natural waters, the potential adverse effects of kresoxim-methyl and pyraclostrobin would be relatively low for adult zebrafish but must not be overlooked for zebrafish embryos/larvae (hatching impairment). Our results from the detoxification enzyme study also initially indicated that adult zebrafish had a greater detoxification ability than larvae and that males had a greater detoxification ability than females.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32399841

RESUMO

The production of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) concentrate from cobia liver oil by acetone fractionation of fatty acid salts was investigated in this study. A three-level-three-factor Box-Behnken design was used to evaluate the effects of reaction time, amount of NaOH added, and acetone ratio on the responses (DHA and EPA content and recovery). The results showed that the amount of NaOH added was the most important factor in the process. The DHA content showed an inverse relation with EPA content and recovery, whereas its content increased proportionally with the amount of NaOH added. With a reaction time of 1.51 h, amount of NaOH added at 0.65 times the molar equivalent of free fatty acid (FFA), and acetone ratio at 13.92, a maximum recovery of DHA + EPA was 98.14%, and the obtained concentrate contained 71.23% DHA + EPA. Finally, the lipase-catalyzed esterification of the DHA + EPA concentrate with glycerol was carried out. The acetone fractionation of fatty acid salts is an efficient technique for producing DHA +EPA concentrate. The DHA +EPA concentrate can be used as starting materials for the production of functional lipids to provide n-3 polyunsaturated fatty acids to the consumers.

9.
BMC Infect Dis ; 20(1): 328, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32381049

RESUMO

BACKGROUND: Brain abscess due to the Nocardia genus is rare and usually found in immunocompromised patients. The most common subtype implicated is Nocardia farcinica while brain abscess due to Nocardia brasiliensis is comparatively rare. Diagnosis of brain abscess is based mainly on bacteriological culture from pus collected at the site of infection, and brain imaging. Stereotaxic aspiration or surgical resection combined with adequate duration of treatment with antibiotics to which the bacteria are sensitive represent effective treatment strategies. CASE PRESENTATION: We report a rare case of brain abscess caused by Nocardia brasiliensis in a non-immunocompromised patient. He admitted to our hospital twice with a headache. Stereotaxic aspiration was performed at the patient's first appointment at the hospital, and a craniotomy was used to excise the lesion during subsequent abscess recurrence. CONCLUSION: Early diagnosis, reasonable surgical intervention, and adequate duration of treatment with effective antibiotics are critical for treating brain abscess.

10.
Chem Commun (Camb) ; 56(41): 5476-5479, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32391821

RESUMO

Herein, iron-terpyridine complexes with the iron centers at different initial valence states were utilized as homogeneous catalysts for the degradation of phenol in water. The iron(iii)-terpyridine complex induced the formation of more high-valent iron-oxo centers and hydroxyl radicals than the iron(ii)-terpyridine complex, leading to a higher catalytic activity.

11.
Sci Rep ; 10(1): 8372, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32433520

RESUMO

The regeneration capacity of knee cartilage can be enhanced by applying periosteal grafts, but this effect varies depending on the different sources of the periosteal grafts applied for cartilage formation. Tibia periosteum can be used to enhance cartilage repair. However, long-term analysis has not been conducted. The endochondral ossification capacity of tibia periosteum during cartilage repair also needs to be investigated. In this study, both vascularized and non-vascularized tibia periosteum grafts were studied to understand the relationship between tissue perfusion of the periosteum graft and the effects on cartilage regeneration and bone formation. Furthermore, anti-ossification reagents were added to evaluate the efficacy of the prevention of bone formation along with cartilage regeneration. A critical-size cartilage defect (4 × 4 mm) was created and was covered with an autologous tibia vascularized periosteal flap or with a non-vascularized tibia periosteum patch on the knee in the rabbit model. A portion of the vascularized periosteum group was also treated with the anti-osteogenic reagents Fulvestrant and IL1ß to inhibit unwanted bone formation. Our results indicated that the vascularized periosteum significantly enhanced cartilage regeneration in the cartilage defect region in long-term treatment compared to the non-vascularized group. Furthermore, the addition of anti-osteogenic reagents to the vascularized periosteum group suppressed bone formation but also reduced the cartilage regeneration rate. Our study using vascularized autologous tissue to repair cartilage defects of the knee may lead to the modification of current treatment in regard to osteoarthritis knee repair.

12.
Small ; : e1907575, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32432833

RESUMO

Carbon nanotubes (CNTs) with hydrophobic and atomically smooth inner channels are promising for building ultrahigh-flux nanofluidic platforms for energy harvesting, health monitoring, and water purification. Conventional wisdom is that nanoconfinement effects determine water transport in CNTs. Here, using full-atomistic molecular dynamics simulations, it is shown that water transport behavior in CNTs strongly correlates with the electronic properties of single-walled CNTs (metallic (met) vs semiconducting (s/c)), which is as dominant as the effect of nanoconfinement. Three pairs of CNTs (i.e., (8,8)met , 10.85 Å vs (9,7)s/c , 10.88 Å; (9,8)s/c , 11.53 Å vs (10,7)met , 11.59 Å; and (9,9)met , 12.20 Å vs (10,8)s/c , 12.23 Å) are used to investigate the roles of diameter and metallicity. Specifically, the (9,8)s/c can restrict the hydrogen-bonding-mediated structuring of water and give the highest reduction in carbon-water interaction energy, providing an extraordinarily high water flux, around 250 times that of the commercial reverse osmosis membranes and approximately fourfold higher than the flux of the state-of-the-art boron nitrate nanotubes. Further, the high performance of (9,8)s/c is also reproducible when embedded in lipid bilayers as synthetic high-water flux porins. Given the increasing availability of high-purity CNTs, these findings provide valuable guides for realizing novel CNT-enhanced nanofluidic systems.

13.
Biosci Rep ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32441737

RESUMO

BACKGROUND: This study was designed to explore the regulatory mechanisms and influences of cotinine on deep vein thrombosis (DVT) in rats via the toll-like receptors / nuclear factor kappa binding (TLR-4/NF-κB) pathway. PATIENTS AND METHODS: In this experimental study, 30 SD rats were randomly assigned to control group, sham operation group, model group, cotinine (10 µg/kg) group, and model + cotinine (10 µg/kg) group. The TXB2, 6-keto-PGF1α, PAI, t-PA, TLR4, NF-κB, and p65 mRNA and protein expression and tissue changes were analyzed by ELISA, HE staining, RT-PCR, and Western Blot. RESULTS: There was no significant difference between the control and sham operation groups (P>0.05). The model and cotinine groups showed significantly higher mRNA and protein levels of TXB2, IL-6 and TNF-α, PAI, TLR-4, and NF-κB, and significantly lower levels of 6-keto-PGF1α and t-PA than the control and sham operation groups (P<0.05), and the model + cotinine group showed significantly higher mRNA and protein levels of TXB2, IL-6 and TNF-α, PAI, TLR-4, and NF-κB and significantly lower levels of 6-keto-PGF1α and t-PA than the model group (P<0.05). CONCLUSION: Cotinine can aggravate thrombus and inflammation in rats with DVT, and the mechanism may be associated with the activation of the TLR-4/NF-κB inflammatory signaling pathway.

14.
EBioMedicine ; 55: 102766, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32408110

RESUMO

BACKGROUND: The composition of the bile acid (BA) pool is closely associated with obesity and is modified by gut microbiota. Perturbations of gut microbiota shape the BA composition, which, in turn, may alter important BA signaling and affect host metabolism. METHODS: We investigated BA composition of high BMI subjects from a human cohort study and a high fat diet (HFD) obesity prone (HF-OP) / HFD obesity resistant (HF-OR) mice model. Gut microbiota was analysed by metagenomics sequencing. GLP-1 secretion and gene regulation studies involved ELISA, qPCR, Western blot, Immunohistochemistry, and Immunofluorescence staining. FINDINGS: We found that the proportion of non-12-OH BAs was significantly decreased in the unhealthy high BMI subjects. The HF-OR mice had an enhanced level of non-12-OH BAs. Non-12-OH BAs including ursodeoxycholate (UDCA), chenodeoxycholate (CDCA), and lithocholate (LCA) were decreased in the HF-OP mice and associated with altered gut microbiota. Clostridium scindens was decreased in HF-OP mice and had a positive correlation with UDCA and LCA. Gavage of Clostridium scindens in mice increased the levels of hepatic non-12-OH BAs, accompanied by elevated serum 7α-hydroxy-4-cholesten-3-one (C4) levels. In HF-OP mice, altered BA composition was associated with significantly downregulated expression of GLP-1 in ileum and PGC1α, UCP1 in brown adipose tissue. In addition, we identified that UDCA attenuated the high fat diet-induced obesity via enhancing levels of non-12-OH BAs. INTERPRETATION: Our study highlights that dysregulated BA signaling mediated by gut microbiota contributes to obesity susceptibility, suggesting modulation of BAs could be a promising strategy for obesity therapy.

15.
Eur J Haematol ; 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32421883

RESUMO

BACKGROUND: In multiple myeloma (MM), impact of specific chromosomal translocations involving IgH (14q21 locus, including t(4;14), t(11;14), and t(14;16) etc.) has been explored extensively. However, over 15% MM patients harboring IgH translocation with undefined partners have long been ignored. METHODS: A prospective non-randomized cohort study with a total of 715 newly-diagnosed MM cases was conducted, 13.6% of whom were t(14;undefined) positive. The whole cohort was divided into four groups: no IgH split (47.7%); t(14;undefined) (13.6%); t(11;14) (17.6%); and t(4;14) or t(14;16) group (21.1%). RESULTS: Median OS for the four groups were 84.2, not reached (NR), 58.7, and 44.2 months respectively, with p values for t(14;undefined) vs. no IgH split, t(11;14), and t(4;14)/t(14;16) groups of 0.197, 0.022 and 0.001, respectively. In bortezomib-based group, the survival advantage gained by t(14;undefined) group was much more significant compared to t(11;14) and t(4;14)/t(14;16) groups. Importantly, t(14;undefined) turned out to be an independent predictive factor for longer OS of MM patients in multivariate analysis, especially in the context of bortezomib-treatment. Similar results were also observed in the PUMCH external validation cohort. CONCLUSION: Collectively, our data confirmed and externally validated the favorable prognosis of the t(14;undefined) groups, especially in the era of novel agents.

16.
Food Chem ; 324: 126899, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353653

RESUMO

Baijiu, a conventional fermented beverage with thousands history, plays a crucial part in physical health of people and social culture in China. The application of high-throughput screening and confirmation of flavor components in the field of authenticity identification and potential function has attracted more and more attention and interest of researchers. With more attention to health, pesticides residues, phthalates, biogenic amines and other hazardous substances remained in Baijiu have also become the quality parameters concerned by consumers. This review aims to present updated and critical overview on the substances analysis of Baijiu by means of hyphenated chromatographic techniques based on various pretreatment approaches in recent years. Subsequently, the advance and main direction of Baijiu composition analysis were evaluated and prospected.

17.
Geroscience ; 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32418021

RESUMO

Aging is a complex physiological process associated with degenerative disorder of metabolism and immune function, which contributes to the occurrence of senile diseases. The gut microbiota affects systemic inflammation in aging processes probably through metabolism, but their relationship is still unclear. In this study, 16S-rRNA-sequencing technology, gas chromatography-time-of-flight mass spectrometry (GC-TOFMS)-based metabolic profiling, and immune factor analysis combined with advanced differential and association analysis were employed to investigate the correlation between the microbiome, metabolome, and immune factors in male Wistar rats across lifespan. Our findings showed significant changes in the ileum microbiome and serum metabolome compositions across aging process. A two-level strategy was applied to demonstrate that key metabolites associated with age such as 4-hydroxyproline, proline, and lysine were clustered together and positively correlated with beneficial microbes including Bifidobacterium, Lactobacillus, and Akkermansia. Function analysis explored association between serum metabolite class and specific gut bacteria's metabolism pathways. Further correlation analysis on all the alteration patterns provided an interaction network of main immune factors such as IL-10, IgA, IgM, and IgG with key gut bacteria and serum metabolites. This study offers new insights into the relationship between immune factors, serum metabolome, and the gut microbiome.

18.
J Agric Food Chem ; 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32419456

RESUMO

The current study developed an ultra-high performance liquid chromatography tandem mass spectrometry method to simultaneously analyze cascade metabolites of acrylamide in urine of rats and humans, including acrylamide, glycidamide, N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA), N-acetyl-S-(2-carbamoylethyl)-L-cysteine-sulfoxide, N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine and N-acetyl-S-(1-carbamoyl-2-hydroxyethyl)-L-cysteine. A tandem solid-phase extraction procedure was novelly used to purify all metabolites at one time from human urine. The rapid analysis showed high sensitivity with LOD and LOQ ranges of 0.1-0.8 ng/mL and 0.4-5.8 ng/mL, respectively, and achieved acceptable within-laboratory reproducibility (RSD<12.0%) and spiking recovery (92.2%-117.3%) within 8 min per sample. Approximately 70.7% and 63.0% of ingested acrylamide was recovered during the toxicokinetic analysis from urine of male and female rats, respectively. For non-smoking participants, the urinary levels of acrylamide and glycidamide were higher in men than women, whereas the urinary concentration of AAMA showed the opposite behavior. The current analysis provides methodological support of cascade metabolites of acrylamide for the dietary short-term internal exposure assessment of acrylamide.

19.
Food Chem ; 326: 126960, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32413752

RESUMO

In this study, intermolecular copigmentation between five primary wine monoglucosidic anthocyanins (cyanidin-3-O-glucoside, peonidin-3-O-glucoside, delphinidin-3-O-glucoside, petunidin-3-O-glucoside, and malvidin-3-O-glucoside) and three common wine phenolics (gallic acid, (-)-epicatechin, and quercetin-3-O-glucoside) were investigated through experimental and theoretical methods, and the influence of substituent pattern of anthocyanin B ring was studied emphatically. Chromatic and thermodynamic analysis showed there were great differences among these different pigment-copigment systems. Spatial conformations of the 15 copigmentation complexes were obtained through theoretical calculation, and diverse π-π stacking modes were observed. These results indicated that the substituent pattern of anthocyanin B ring had significant impact on its affinity to copigments, and more, the structures of pigments and copigments determined the color expression and stability of copigmentation together.

20.
Food Chem ; 326: 126969, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32438229

RESUMO

Biocompatible magnetic molecularly imprinted polymers (BMMIPs) were prepared with Zein for the first time, and were used to enrich tetracycline compounds selectively. Innovative combination of BMMIPs and electrochemistry to obtain lower detection line to satisfy industrial detection demands. Using Zein as the crosslinking agent, the polymers were synthesized on the surface of Fe3O4 particles. The scanning electron microscope, transmission electron microscope and X-ray diffraction technologies were used to characterize BMMIPs. Through optimization, BMMIPs attained large adsorption capacity (236.40 mg/g) with fast kinetics (40 min) and followed the Langmuir isotherm and pseudo-second-order kinetic models. BMMIPs had good recognition ability, the selective factors of oxytetracycline, chlortetracycline, doxycycline were 4.78, 4.23, and 3.39, respectively. Excellent linearity was attained in the range of 0.025-500 µg/mL, with low detection limits and low quantitation limits of 0.025 and 0.083 µg/mL. According to our exploring, BMMIPs was ideal materials for enrichment of tetracycline in complex biological samples.

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