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1.
Microb Pathog ; : 104067, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32061915

RESUMO

Helicobater pylori (H. pylori) is the most important bacteria known to be associated with various gastroduodenal diseases. virB11 gene is a structural gene of tfs3a genes cluster in the plasticity region of H. pylori. In this study, the structure and biology of virB11 gene were analyzed and elucidated with bioinformatics analysis. After cloning, expression and purification, VirB11 protein was generated for the cytotoxicity to GES-1 cells and the anti-VirB11 protein antibody production for localization and interaction proteins analysis. The results showed that VirB11 protein is a hydrophilic protein, mainly locates in cell membrane. IL-8 productions from GES-1 cells co-culture with VirB11 protein were increased gradually with time (p < 0.001). The interaction proteins of VirB11 protein were F0F1 ATP synthase subunit alpha, ATP synthase subunit beta and isocitrate dehydrogenase. We demonstrate that VirB11 protein possesses cytotoxicity and potentially plays important roles in ATP metabolism to provide energy in the course of H. pylori infection.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117994, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31951941

RESUMO

A cysteamine functionalized core shelled nanoparticles (Au@Ag-CysNPs) was presented for simultaneous and rapid detection of sodium thiocyanate (STC) and benzoic acid (BA) preservatives in liquid milk using surface-enhanced Raman spectroscopy (SERS) technique. A spectrum covering 350-2350 cm-1 region was selected to detect STC with concentrations ranging from 0.5 to 10 mg/L and BA with concentrations ranging from 15 to 240 mg/L in milk samples. Characterization of nanoparticles using high-resolution TEM confirmed that the successful synthesis of Au@AgNPs with core (gold) size of 28 nm and shell (silver) thickness of about 5 nm was grafted with 120 µL of 0.1 nM cysteamine hydrochloride. Results showed that Au@Ag-CysNPs could be used to detect STC up to 0.03 mg/L with a limit of quantification (LOQ) of 0.039 mg/L and a coefficient of determination (R2) of 0.9833 in the milk sample. For detecting BA, it could be screened up to 9.8 mg/L with LOQ of 10.2 mg/L and R2 of 0.9903. The proposed substrate was also highly sensitive and the employed method involved only minor sample pretreatment steps. It is thus hoped that the new substrate could be used in the screening of prohibited chemicals in complex food matrices in future studies.

3.
Analyst ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31951224

RESUMO

In this study, a 4-aminobenzenethiol-functionalized core-shell silver-coated gold nanoparticle (Au@Ag-4ABT NP) system was designed for the rapid sensing of carbendazim (CBZ) using a combination of naked-eye colorimetry and surface-enhanced Raman spectroscopy (SERS) dual-channel approach. Under alkaline conditions, the deprotonated CBZ species could interact with Ag surfaces via the N-Ag-O and N-Ag-N bonds. As a result, the neighboring Au@Ag-4ABT NPs would come closer through π-π interactions inducing the aggregation of Au@Ag-4ABT NPs. The aggregation of nanoparticles caused changes in the optical properties of the colloidal system, allowing observation with naked eyes, while the generation of more localized surface plasmon resonance "hotspots" between the adjacent Au@Ag nanoparticles permitted monitoring by the SERS technique. The proposed method showed effective sensitivity toward CBZ with limit of detection and limit of quantitation values of 37 and 122 ppb, respectively. In addition, the proposed dual-channel assay could serve as a simple and rapid method for sensing CBZ in tap water, cauliflower, and pear juice within 30 min.

4.
Cell Death Dis ; 11(1): 32, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949130

RESUMO

Circular RNAs (circRNAs) have been identified play a vital role in various different types of cancer via sponging miRNAs (microRNAs). However, their role in lung adenocarcinoma (LUAD) remains largely unclear. In this study, we systematically characterized the circRNA expression profiles in the LUAD cancer tissues and paired adjacent non-cancerous tissues. Three circRNAs were found to be significantly upregulated. Among them, has-circRNA-002178 was further confirmed to be upregulated in the LUAD tissues, and LUAD cancer cells. Subsequently, we also found has-circRNA-002178 could enhance PDL1 expression via sponging miR-34 in cancer cells to induce T-cell exhaustion. More importantly, circRNA-002178 could be detected in exosomes of plasma from LUAD patients and could serve as biomarkers for LUAD early diagnosis. Finally, we found circRNA-002178 could be delivered into CD8+ T cells to induce PD1 expression via exosomes. Taken together, our study revealed that circRNA-002178 could act as a ceRNA to promote PDL1/PD1 expression in lung adenocarcinoma.

5.
World J Surg Oncol ; 18(1): 9, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931816

RESUMO

OBJECTIVE: Provide an updated and comprehensive evaluation of the prognostic value of the albumin-fibrinogen ratio (AFR) and the fibrinogen-prealbumin ratio (FPR) for patients with cancer. MATERIALS AND METHODS: Four databases (PubMed, Web of Science, Cochrane Library, and WanFang) were searched. The primary endpoints were overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS). Pooled data were synthesized using StataMP 14 and expressed as hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: This update examined 19 studies (7282 cases) that assessed the correlation of AFR with cancer prognosis. Pooled univariate and multivariate analyses indicated significant correlations of low AFR with poor OS (HR 2.18, 95%CI 1.87-2.55 and HR 1.75, 95%CI 1.54-2.00, respectively), poor DFS (HR 1.89, 95%CI 1.54-2.32 and HR 1.51, 95%CI 1.29-1.76, respectively), and poor PFS (HR 1.68, 95%CI 1.42-1.99 and HR 1.48, 95%CI 1.16-1.88, respectively). Pooled univariate and multivariate analyses of 6 studies (2232 cases) indicated high FPR significantly correlated with poor OS (HR 2.37, 95%CI 2.03-2.77 and HR 1.97, 95%CI 1.41-2.77, respectively). One study reported that high FPR correlated with poor DFS (univariate analysis: HR 2.20, 95%CI 1.35-3.57; multivariate analysis: HR 1.77, 95%CI 1.04-2.99) and one study reported a correlation of high FPR with poor PFS in univariate analysis alone (HR 1.79, 95%CI 1.11-2.88). CONCLUSION: A low AFR and a high FPR correlated with increased risk of cancer mortality and recurrence. AFR and FPR may be promising prognostic markers for cancers.

6.
Mol Ther ; 28(1): 293-303, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31611143

RESUMO

Stargardt disease (STGD) is an autosomal recessive retinal disorder caused by a monogenic ABCA4 mutation. Currently, there is no effective therapy to cure Stargardt disease. The replacement of mutated ABCA4 with a functional gene remains an attractive strategy. In this study, we have developed a non-viral gene therapy using nanoparticles self-assembled by a multifunctional pH-sensitive amino lipid ECO and a therapeutic ABCA4 plasmid. The nanoparticles mediated efficient intracellular gene transduction in wild-type (WT) and Abca4-/- mice. Specific ABCA4 expression in the outer segment of photoreceptors was achieved by incorporating a rhodopsin promoter into the plasmids. The ECO/pRHO-ABCA4 nanoparticles induced substantial and specific ABCA4 expression for at least 8 months, 35% reduction in A2E accumulation on average, and a delayed Stargardt disease progression for at least 6 months in Abca4-/- mice. ECO/plasmid nanoparticles constitute a promising non-viral gene therapy platform for Stargardt disease and other visual dystrophies.

7.
Food Chem ; 310: 125923, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31837530

RESUMO

The design of a novel and reliable plasmonic platform for detecting multiple chemical contaminants in the complex matrix is an exciting topic in the food industry. Herein, a high-performance surface-enhanced Raman scattering (SERS) two-dimensional (2D) nanodot array was designed through liquid-liquid interfacial self-assembly of the core-shell nanoparticles (Au@Ag NPs) and exploited for assessment of dual-fungicides in pear, apple, and orange juices. The 2D Au@Ag nanodot array delivered good uniformity and reproducibility with the substrate-to-substrate relative standard deviation values of 10.51%. This substrate could be used for detecting thiram and thiabendazole in aqueous solutions with the limit of detection of 0.0011 and 0.051 ppm, respectively. Furthermore, satisfactory recoveries ranging from 76-134% for the juices were obtained, demonstrating that the high-throughput 2D Au@Ag nanodot arrays are promising for their applications as sensitive SERS platforms for monitoring chemical contaminants in food products, especially in the beverage industry.

8.
Ultrason Sonochem ; 60: 104733, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31514109

RESUMO

The effects of multi-frequency ultrasound assisted freezing on the freezing rate, microstructure, quality properties (drip loss, firmness, total calcium content, l-ascorbic acid content and total phenol content) of potatoes were studied. The results indicated that the freezing effects of multi-frequency ultrasound was better than those of single-frequency ultrasound. Multi-frequency ultrasound could significantly increase the freezing rate and preserve the quality of frozen samples better. With increase in the number of ultrasonic frequencies, the freezing effect was more obvious. In addition, scan electron microscopy (SEM) images showed that the ice crystals formed by the multi-frequency ultrasonic treatment were fine and uniformly distributed, which caused less damage to the frozen potato samples. From the analysis of the quality attributes, the nutritional values of the samples after multi-frequency ultrasonic treatment was higher, but attention should be paid to the negative influence of the hydroxyl radical generated by the multi-frequency ultrasound.

9.
Analyst ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31820748

RESUMO

Raman spectroscopy has been employed for studying the hydrogen bonding states of water molecules for decades, however, Raman imaging data contain thousands of spectra, making it challenging to obtain information on water with different hydrogen bonds. In the current study, a novel method combining confocal Raman microscopy (CRM) imaging with the iterative curve fitting algorithms was developed to determine the distribution of water contents at the cellular level and water states with different hydrogen bonds in apple tissues. Raman imaging data ranging from 2700 to 3800 cm-1 were acquired from whole cells in the apple tissue, which were then decomposed into seven sub-peaks using the fixed-position Gaussian iterative curve fitting (FPGICF) algorithm. The content and hydrogen bonding states of cellular water were calculated as the area sum of the OH stretching vibration and the area ratio of DA-OH over DDAA-OH stretching vibration or the number of hydrogen bonds of each water molecule, respectively. Finally, the area of each sub-peak, the area sum of the OH stretching vibration, and the area ratio of DA-OH over DDAA-OH stretching vibration were used to visualize the distribution of each sub-peak, water contents and water states with different hydrogen bonds, respectively. In addition, it was found that the number of hydrogen bonds of each water molecule could also be considered as a criterion to describe the hydrogen bond states of water in apple tissues. The availability of such information should provide new insights for future study of cellular water in other food materials.

10.
World J Clin Cases ; 7(22): 3698-3710, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31799294

RESUMO

BACKGROUND: Hypertension is prevalent in the general population and is regarded as the second leading cause of renal damage and dysfunction, outnumbered only by diabetes. However, the mechanisms remain unclear. AIM: To investigate podocyte injury induced by hypertension in the early course without massive proteinuria or renal dysfunction. METHODS: The hypertension group comprised 18 patients with hypertension accompanied by microalbuminuria, diagnosed with hypertensive renal injury according to biopsy results. For a comparison of pathological changes in renal tissue, control group 1 comprised 10 healthy volunteers, and control group 2 comprised 16 patients who underwent surgery for renal trauma. RESULTS: The hypertension group had significantly higher blood pressure (P = 0.000) and microalbuminuria (P = 0.000) compared with control group 1. In the hypertension group, urinary podocytes were detected following positive staining of podocyte-specific nephrin and/or CD2-associated protein (CD2AP) in urine sediment. Podocyte foot process fusion and a significant decrease in nephrin and/or CD2AP expression in glomeruli were observed in the hypertension group compared with control group 2. This indicated that hypertension caused podocyte injury and detachment from the glomerular basement membrane, which was consistent with urinary detection of podocytes. CONCLUSION: Our results suggest that podocyturia appears early in the course of hypertensive renal injury, and may be a sensitive marker for early prediction of hypertensive renal injury.

11.
Rev Med Virol ; : e2087, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811676

RESUMO

Coxsackievirus A6 (CV-A6) has been associated with increasingly occurred sporadic hand-foot-mouth disease (HFMD) cases and outbreak events in many countries. In order to understand epidemiological characteristics of CV-A6, we collected the information describing HFMD caused by CV-A6 to describe the detection rate, severe rate and onychomadesis rate, which is defined as one or more nails defluvium, caused by CV-A6 from 2007 to 2017. The results showed that there was an outbreak of CV-A6 every other year, and overall trend of the epidemic of CA6-associated HFMD was increasing in China. The detection rate of CV-A6 in other countries was 32.0% (95% CI: 25.0%~40.0%) before 2013 and 28.0% (95% CI: 20.0%~36.0%) after 2013, respectively. Although the severe rate of HFMD caused by CV-A6 was low (0.10%, 95% CI: 0.01%~0.20%), CV-A6 can cause a high incidence of onychomadesis (28.0%, 95%CI: 21.9%-34.3%). Thus, it would be worthwhile to research and develop an effective multivalent vaccine for CV-A6 to achieve a more powerful prevention of HMFD.

12.
J Pain Res ; 12: 3127-3133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31814754

RESUMO

Purpose: Our study aims to investigate the distribution of pain symptoms and the association between pain symptoms and clinical parameters in patients with adenomyosis. Patients and methods: The clinical and pathological data of 291 patients diagnosed with adenomyosis in the Obstetrics and Gynecology Department of Peking Union Medical College Hospital from March 2012 to September 2015 were collected, and analyzed in regard to the pain symptoms. Results: The median age at disease onset was 34 years. 71.8% of the patients had pain symptoms (pain group) and 28.2% had no pain symptoms (painless group). Patients with symptoms accompanied by dysmenorrhea accounted for 68%, among which 30.3% were mild, 36.9% were moderate, and 32.8% severe, while 56.1% presented with progressive pain. Through comparison, significant differences were identified between the pain and painless groups with regard to age at diagnosis (P=0.009), age at onset of disease (P=0.008), and level of pre-surgical CA125 (P<0.001), as well as proportion of patients with rectal irritation (P=0.008), elevated CA125 level (P<0.001), thickened myometrial layer (P<0.001) and concurrent endometriosis (P=0.001). In the multivariable analysis, an elevated level of pre-surgical CA125 (P<0.001) and thickened posterior myometrial layer (P=0.023) were both independent risk factors for the morbidity of pain symptoms. Similar results except for the difference in rectal irritation were noticed when we made further comparison between the dysmenorrhea and non-dysmenorrhea groups in adenomyosis patients. Conclusion: Our research analyzes the clinical features related to pain symptoms in patients with adenomyosis, which may provide clues for the possible presurgical diagnosis of adenomyosis, as well as references for pain management of adenomyosis.

13.
Dis Markers ; 2019: 4796598, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827634

RESUMO

Background: Geriatric Nutritional Risk Index (GNRI) has been widely used to assess the nutritional status in a variety of human pathological conditions, but the prognostic value of the GNRI in malignancies has not been evinced. Methods: Relevant studies updated on Jul 27, 2019, were retrieved in available databases, including PubMed, Web of Science, Cochrane library, Chinese CNKI, and Chinese Wan-fang. Hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted and pooled by using STATA 14. Results: A total of 15 studies involving 8,046 subjects were included in this meta-analysis. Meta-analysis results evinced that low GNRI was associated with poor OS (HR = 1.95, 95% CI: 1.49-2.56, p ≤ 0.001), poor CSS (HR = 1.81, 95% CI: 1.49-2.19, p ≤ 0.001), poor DFS (HR = 1.67, 95% CI: 1.28-2.17, p ≤ 0.001), and poor PFS (HR = 1.68, 95% CI: 1.28-2.21, p ≤ 0.001), and the correlation of GNRI with OS was not changed when stratified by possible confounding factors, suggesting that malignancy patients with low GNRI would suffer from reduced survival rate and increased recurrence rate. Moreover, low GNRI was also associated with postoperative complications in malignancies. Conclusions: In summary, GNRI is associated poor prognosis in human malignancies, and GNRI should be used as a predictive indicator of adverse outcomes during malignancy treatment.

14.
J Synchrotron Radiat ; 26(Pt 6): 2075-2080, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31721753

RESUMO

The upgrade of the laser pump time-resolved X-ray probes, namely time-resolved X-ray absorption spectroscopy (TR-XAS) and X-ray diffraction (TR-XRD), implemented at the Beijing Synchrotron Radiation Facility, is described. The improvements include a superbunch fill, a high-efficiency fluorescence collection, an efficient spatial overlap protocol and a new data-acquisition scheme. After upgrade, the adequate TR-XAS signal is now obtained in a 0.3 mM solution, compared with a 6 mM solution in our previous report. Furthermore, to extend application in photophysics, the TR-XAS probe is applied on SrCoO2.5 thin film. And for the first time, TR-XAS is combined with TR-XRD to simultaneously detect the kinetic trace of structural changes in thin film.

15.
Theranostics ; 9(23): 6885-6900, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31660075

RESUMO

Cancer remains a daunting and cureless disease, which is responsible for one-sixth of human deaths worldwide. These mortality rates have been expected to rise in the future due to the side effects of conventional treatments (chemotherapy, radiotherapy, and surgery), which can be addressed by applying nanomedicine. In order to escape from biological barriers, such nanomedicine should be mimicked and designed to be stealthy while navigating in the bloodstream. To achieve this, scientists take advantage of erythrocytes (red blood cells; RBCs) as drug carriers and develop RBC membrane (RBCm) coating nanotechnology. Thanks to the significant advances in nanoengineering, various facile surface functionalization methods can be applied to arm RBCm with not only targeting moieties, but also imaging agents, therapeutic agents, and nanoparticles, which are useful for theranostic nanomedicine. This review focuses on refunctionalization of erythrocyte-based nanomedicine for enhancing cancer-targeted drug delivery.

16.
Ann Transl Med ; 7(16): 388, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31555702

RESUMO

Background: The aim of this prospective study was to screen and combine effective biomarkers to improve their diagnostic performance in detecting intestinal barrier dysfunction in patients after major abdominal surgery. Methods: Patients undergoing major abdominal surgery were enrolled after signing informed consent in this study. The serum concentrations of α-GST, DAO, D-lactate, citrulline and I-FABP were detected 24 hours before and after surgery. The diagnostic performance of five biomarkers on intestinal barrier dysfunction was assessed using logistic regression models and receiver operating characteristic (ROC) curve analyses. Results: Thirty-nine patients with major abdominal surgery were enrolled in and successfully completed this study. ROC analysis revealed that the sensitivities of D-lactate, citrulline and I-FABP were very high (0.91, 0.91 and 1.00, respectively), but the specificities of these biomarkers were less than 0.70. The sensitivity of DAO was very low [0.25; 95% confidence interval (CI), 0.05-0.57], but its specificity was high (0.92; 95% CI, 0.75-0.99). The accuracies of D-lactate and I-FABP were very high, and the areas under the curves (AUCs) of the biomarkers were 0.84 (95% CI, 0.68-0.93) and 0.81 (95% CI, 0.65-0.92), respectively. Different combinations of five biomarkers were also analysed. The sensitivity, specificity and AUC values of the combination of I-FABP, citrulline and D-lactate were 1.00, 0.74 and 0.89, respectively. These results were similar to those derived from the combination of α-GST, DAO, D-lactate, citrulline and I-FABP (P=1.000). Conclusions: The combination of serum D-lactic acid, citrulline and I-FABP greatly improved the diagnostic performance for identifying intestinal barrier dysfunction in patients after major abdominal surgery.

17.
Clin Nutr ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31542246

RESUMO

OBJECTIVES: The aim of this study was to systematically assess the nutrition care procedures in nutrition guidelines for cancer patients and identify gaps limiting evidence-based practise. METHODS: A systematic search of databases and websites was conducted to identify nutrition guidelines for cancer patients. The quality of the eligible guidelines was evaluated by using the Appraisal of Guidelines for Research and Evaluation (AGREE II). The Measurement Scale of Rate of Agreement (MSRA) was used to assess the scientific agreement of formulated recommendations for nutrition care procedures in the guidelines (2017-2019), and evidence supporting these recommendations was extracted and analysed. RESULTS: Seventeen nutrition guidelines for cancer patients were identified. Only European Society for Clinical Nutrition and Metabolism (ESPEN) and Australian guidelines have a total quality score of more than 60%, which is worthy of clinical recommendation. Twelve guidelines (2017-2019) were included to further analyse the heterogeneity and causes of nutrition care procedures, and we found that the content and tools of nutrition screening and assessment, the application of immune nutrients, and the selection of nutritional support pathways were heterogeneous. The main reasons for the heterogeneity of nutrition care procedures were insufficient attention to nutrition risk screening, differences in recommendations for nutrition assessment, immune nutrients and nutritional support, unreasonable citation of screening and assessment evidence, preference of developers, and lack of evidence of high-quality research on energy and nitrogen demand. In addition, the fairness and propensity of the guidelines for the selection of evidence for different cancer patients are also potential reasons for the heterogeneity of nutritional care procedures. CONCLUSIONS: The quality of the nutrition guidelines for cancer patients was highly variable. The nutrition care procedures were heterogeneous among the different guidelines in the last 3 years. Specific improvement of the factors leading to the heterogeneity of nutrition care procedures will be a reasonable and effective way for developers to upgrade the nutrition care procedures in the guidelines for cancer patients.

18.
Environ Sci Pollut Res Int ; 26(29): 29763-29779, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407264

RESUMO

Dibutyl phthalate (DBP), a persistent environmental pollutant, can induce neural tube abnormal development in animals. The possible effects of DBP exposure on human neural tube defects (NTDs) remain elusive. In this study, the distribution of DBP in the body fluid of human NTDs was detected by GC-MS. Then, chick embryos were used to investigate the effects of DBP on early embryonic development. Oxidative stress indicators in chick embryos and the body fluid of human NTDs were detected by ELISA. The cell apoptosis and total reactive oxygen species (ROS) level in chick embryos were detected by whole-mount TUNEL and oxidized DCFDA, respectively. The study found that the detection ratio of positive DBP and its metabolites in maternal urine was higher in the NTD population than that in normal controls. 8-hydroxy-2 deoxyguanosine (8-OHDG) and malondialdehyde (MDA) were evidently upregulated and superoxide dismutase (SOD) was observably downregulated in amniotic fluid and urine. Animal experiments indicated that DBP treatment induced developmental toxicity in chick embryos by enhancing the levels of oxidative stress and cell apoptosis. MDA was increased and SOD was decreased in DBP-treated embryos. Interestingly, the supplement of high-dose choline (100 µg/µL), not folic acid, could partially restore the teratogenic effects of DBP. Our data collectively suggest that the incidence of NTDs is closely associated with DBP exposure. This study may provide new insight for NTD prevention.


Assuntos
Galinhas/metabolismo , Colina/metabolismo , Dibutilftalato/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Defeitos do Tubo Neural/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Líquidos Corporais/metabolismo , Embrião de Galinha , Galinhas/crescimento & desenvolvimento , Dibutilftalato/urina , Poluentes Ambientais/urina , Feminino , Ácido Fólico/metabolismo , Humanos , Exposição Materna/efeitos adversos , Teratogênese/efeitos dos fármacos
19.
Food Chem ; 301: 125240, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387040

RESUMO

Cold plasma is an emerging technology increasingly applied in the agri-food industry. For fruit and vegetables, enzymatic browning is a common phenomenon, causing quality deterioration. The objective of this study was to illustrate the effect of microscale atmospheric-pressure plasma jet (µAPPJ) plasma on the horseradish peroxidase (HRP). Results showed that after plasma treatment for 10 min, the residual activity of HRP was decreased to around 17%, and modification of secondary and tertiary structures were confirmed. The atomic force microscope (AFM) analysis revealed that the aggregation of enzyme protein was enhanced with prolonging treatment time. It was concluded that the activity of HRP could be reduced with destruction of structures and deformation of microstructure induced by µAPPJ plasma. The current study attempted to provide new idea for inhibiting browning enzymes of fruit and vegetables with plasma technology through deeper understanding of the interaction mechanism of plasma active species with enzymes.


Assuntos
Temperatura Baixa , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Gases em Plasma/farmacologia , Pressão Atmosférica
20.
Food Chem ; 300: 125143, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326674

RESUMO

Tropomyosin (TM), a myofibrillar protein, is a major allergen in most crustaceans including king pawn (Litopenaeus vannamei). In this study, the structural modifications and allergenic response of TM in fresh king prawn as induced by cold argon plasma jet (CAPJ) were examined. The result showed that the level of α-helix structures declined as treatment time progressed, while the level of ß-sheets and random coils increased. The free sulfhydryl groups decreased as CAPJ treatment progressed due to the formation of disulphide bonds while surface hydrophobicity increased until equilibrium values. In addition, after 15 min of plasma exposure, the maximum reduction recorded for IgE and IgG binding capacities were 17.6% and 26.87% respectively as revealed by ELISA test. These findings correlated with the occurrence of protein unfolding and denaturation, evident by complementary structural analyses conducted. The study indicates that non-thermal plasma maybe a promising tool for developing hypoallergenic food products.


Assuntos
Alérgenos/química , Imunoglobulina E/imunologia , Penaeidae/imunologia , Gases em Plasma/química , Tropomiosina/química , Tropomiosina/imunologia , Animais , Argônio , Ensaio de Imunoadsorção Enzimática , Hipersensibilidade Alimentar , Humanos , Penaeidae/química
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