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1.
J Dairy Sci ; 107(6): 3400-3412, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38135045

RESUMO

Hypothyroidism has been found to have an effect on the nutritional composition of human milk during pregnancy. This study aims to explore the combined influence of rheological properties, macronutrient content, particle size, and the zeta potential of milk fat globules, as well as the composition of milk fat globule membrane (MFGM) proteins on the quality of human milk in gestational hypothyroidism. The study revealed that human milk from the group with hypothyroidism during pregnancy (AHM) was less viscoelastic and stable when compared with normal pregnancy group human milk (NHM). Furthermore, the particle size and macronutrient content of NHM were found to be larger than that of AHM. In contrast, the zeta potential of AHM was greater than that of NHM. The sodium dodecyl sulfate-PAGE results disclosed that the composition of MFGM proteins in these 2 groups were generally the same, but the content of AHM was lower than that of NHM. In conclusion, this study confirms that hypothyroidism during pregnancy can have a significant effect on the quality of human milk.


Assuntos
Hipotireoidismo , Leite Humano , Reologia , Feminino , Humanos , Gravidez , Leite Humano/química , Hipotireoidismo/veterinária , Glicolipídeos
2.
Front Endocrinol (Lausanne) ; 15: 1422470, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39170736

RESUMO

Objectives: To explore the relationship between estradiol (E2) and the incidence of hyperuricemia (HUA) in adult women and to explore whether glucolipid metabolism disorders play a mediating role in mediating this relationship. Methods: A total of 2,941 participants aged 20-65 years were included in the National Health and Nutrition Examination Survey (NHANES) 2013-2016. Multivariate logistic regression analysis was performed to evaluate the correlations of E2 with HUA. Multivariate linear regression analysis was performed to evaluate the associations between E2 and triglyceride (TG), total cholesterol (TC), and the triglyceride-glucose index (TyG). The restricted cubic spline (RCS) model was used to further explore the association between E2 and HUA and between TG, TC, and TyG and HUA. Mediation analyses were performed to examine whether TC, TG, and TyG mediated the relationship between E2 and HUA. Results: After adjusting for covariates, logistic regression revealed that ln(E2) was significantly associated with HUA in the female subgroup (p = 0.035) and that the incidence of HUA tended to increase with decreasing ln(E2) (p for trend = 0.026). Linear regression showed that E2 was significantly associated with TC (p = 0.032), TG (p = 0.019), and TyG (p = 0.048). The RCS model showed that ln(E2) was linearly correlated with the incidence of HUA (p-overall = 0.0106, p-non-linear = 0.3030). TC and TyG were linearly correlated with HUA (TC: p-overall = 0.0039, p-non-linear = 0.4774; TyG: p-overall = 0.0082, p-non-linear = 0.0663), whereas TG was non-linearly correlated with HUA. Mediation analyses revealed that TC, TG, and TyG significantly mediated the relationship between ln(E2) and HUA (TC, indirect effect: -0.00148, 7.5%, p = 0.008; TG, indirect effect: -0.00062, 3.1%, p = 0.004; TyG, indirect effect: -0.00113, 5.6%, p = 0.016). Conclusion: In conclusion, this study demonstrated that compared with women aged 20-45 years, women aged 45-55 years and 55-65 years had lower E2 levels and a greater incidence of HUA. E2 levels and the incidence of HUA were negatively associated in female individuals but not in male individuals. In addition, TC, TG, and TyG, which are markers of glucolipid metabolism, played a mediating role in the association between E2 and HUA.


Assuntos
Colesterol , Estradiol , Hiperuricemia , Inquéritos Nutricionais , Triglicerídeos , Humanos , Feminino , Hiperuricemia/epidemiologia , Hiperuricemia/sangue , Pessoa de Meia-Idade , Adulto , Estradiol/sangue , Triglicerídeos/sangue , Idoso , Colesterol/sangue , Adulto Jovem , Glicemia/metabolismo , Glicemia/análise , Masculino , Incidência , Estudos Transversais
3.
J Agric Food Chem ; 72(2): 1391-1404, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38177996

RESUMO

Temperature fluctuations occurring during the cold chain logistics of salmon contribute to lipid oxidation. This study aimed to simulate cold chain interruption through freeze-thaw operations and evaluate the lipidomics data from salmon samples subjected to different numbers of freeze-thaw cycles by using rapid evaporative ionization mass spectrometry (REIMS) combined with an intelligent surgical knife (iKnife). The results indicated significant differences in the relative abundance of characteristic ions among the samples (p < 0.05). A total of 34 ions with variable importance for the projection values ≥1 were identified as potential biomarkers, including m/z 719.4233 ([PCC36:5-NH(CH3)3]-), m/z 337.3134 ([FAC22:1]-), m/z 720.4666 ([PEC35:6-H]-), m/z 309.2780 ([FAC20:1]-), m/z 777.4985 ([PCC40:4-NH(CH3)3]-), m/z 745.4421 ([PCC38:6-NH(CH3)3]-/[PEC38:6-NH3]-), m/z 747.4665 ([PCC38:5-NH(CH3)3]-/[PEC38:5-NH3]-), etc. The degree of lipid oxidation was found to be associated with the number of freeze-thaw cycles, exhibiting the most significant alterations in the relative abundance of lipid ions in the 8T samples. Additionally, sensory evaluation by the CIE-L*a*b* method and volatile analysis by headspace solid-phase microextraction gas chromatography-mass spectrometry demonstrated significant differences (p < 0.05) in color and odor among the salmon samples, with a correlation to the number of freeze-thaw cycles. The primary compounds responsible for alterations in salmon odor were aldehydes with lower odor thresholds. In summary, the iKnife-REIMS method accurately differentiated salmon muscle tissues based on varying levels of lipid oxidation, thus expanding the application of REIMS.


Assuntos
Refrigeração , Salmão , Animais , Espectrometria de Massas/métodos , Lipídeos , Íons , Microextração em Fase Sólida
4.
Food Chem X ; 23: 101705, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39229614

RESUMO

Freezing is one of the most commonly used preservation methods for Bluefin tuna (Thunnus orientalis). However, repeated freezing and thawing would inevitably occur due to the temperature fluctuation, leading to the microstructure damage, lipid oxidation and protein integrity decline of tuna muscle without notable visual appearance change. In this study, we used a rapid evaporative ionization mass spectrometry (REIMS) technique for the real-time determination of the extent of repeated freezing and thawing cycles in tuna fillets. We found significant variance in the relative abundance of fatty acids between bluefin tuna and its fresh counterpart following freeze-thaw cycles. Meanwhile, the difference is statistically significant (p < 0.05). The quality of tuna remains largely unaffected by a single freeze-thaw cycle but significantly deteriorates after freeze-thaw cycles (freeze-thaw count ≥2), and the relative fatty acid content of the ionized aerosol analysis in the REIMS system positively correlated with the number of freeze-thaw cycles. Notably, palmitic acid (C 16:0, m/z 255.23), oleic acid (C 18:1, m/z 281.24), and docosahexaenoic acid (C 22:6, m/z 327.23) displayed the most pronounced changes within the spectrum of fatty acid groups.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38330520

RESUMO

Paralytic shellfish poisoning (PSP) is the most widespread and harmful form of shellfish poisoning with high mortality rate. In this study, a combined desorption electrospray ionization mass spectrometry (DESI-MS) and ultra-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-QqQ/MS) method was established for the detection of PSPs in urine. The method was optimized using a spray solution of methanol and water (1:1, v/v) containing 0.1 % FA, at a flow rate of 2.5 µL·min-1 and an applied voltage of 3 kV. The limit of detection (LOD) for PSPs detection by DESI-MS was in the range of 87-265 µg·L-1, which basically meets the requirements for the rapid screening of PSPs. The LOD for UPLC-QqQ/MS was in the range of 2.2-14.9 µg·L-1, with a limit of quantification (LOQ) of 7.3-49.7 µg·L-1, thus fulfilling the quantitative demand for PSPs in urine. Finally, after spiking the urine samples of six volunteers with PSPs to a concentration of 100 µg·L-1, DESI-MS successfully and efficiently detected the positive samples. Subsequently, UPLC-QqQ/MS was employed for precise quantification, yielding results in the range of 84.6-95.1 µg·L-1. The experimental findings demonstrated that the combination of DESI-MS and UPLC-QqQ/MS enables high-throughput, rapid screening of samples and accurate quantification of positive samples, providing assurance for food safety and human health.


Assuntos
Intoxicação por Frutos do Mar , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Intoxicação por Frutos do Mar/diagnóstico , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massa com Cromatografia Líquida , Limite de Detecção
6.
J Agric Food Chem ; 72(15): 8859-8870, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564481

RESUMO

In this study, an enzymatic reaction was developed for synthesizing pure triacylglycerols (TAG) with a high content of palmitoleic acid (POA) using fish byproduct oil. The characteristics of synthesized structural TAGs rich in POA (POA-TAG) were analyzed in detail through ultrahigh-performance liquid chromatography Q Exactive orbitrap mass spectrometry. Optimal conditions were thoroughly investigated and determined for reaction systems, including the use of Lipozyme TL IM and Novozym 435, 15 wt % lipase loading, substrate mass ratio of 1:3, and water content of 2.5 and 0.5 wt %, respectively, resulting in yields of 67.50 and 67.45% for POA-TAG, respectively. Multivariate statistical analysis revealed that TAG 16:1/16:1/20:4, TAG 16:1/16:1/16:1, TAG 16:1/16:1/18:1, and TAG 16:0/16:1/18:1 were the main variables in Lipozyme TL IM and Novozym 435 enzyme-catalyzed products under different water content conditions. Finally, the fate of POA-TAG across the gastrointestinal tract was simulated using an in vitro digestion model. The results showed that the maximum release of free fatty acids and apparent rate constants were 71.44% and 0.0347 s-1, respectively, for POA-TAG lipids, and the physical and structural characteristics during digestion depended on their microenvironments. These findings provide a theoretical basis for studying the rational design of POA-structural lipids and exploring the nutritional and functional benefits of POA products.


Assuntos
Ácidos Graxos Monoinsaturados , Óleos de Peixe , Água , Triglicerídeos/química , Óleos de Peixe/química , Digestão
7.
Food Chem ; 460(Pt 1): 140532, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39053283

RESUMO

Larimichthys crocea (LYC) holds significant economic value as a marine fish species. However, inaccuracies in labeling its origin can adversely affect consumer interests. Herein, a laser assisted rapid evaporative ionization mass spectrometry (LA-REIMS) and machine learning (ML) was developed for geographical authentication. When compared to iKnife, the LA demonstrated to be superior owing to reduced thermal damage to sample tissue, enhanced automation, and ease of use. Analysis of LYC from six distinct geographical origins across China revealed a total of 798 ions, which were then subjected to six classifiers to establish ML models. Following hyperparameter optimization and feature engineering, the Chi2(15%)-KNN model exhibited the highest training and testing accuracy, achieving 98.4 ± 0.9% and 98.5 ± 1.4%, respectively. This LA-REIMS/ML methodology offers a rapid, accurate, and intelligent solution for tracing the origin of LYC, thereby providing valuable technical support for the establishment of traceability systems in the aquatic product industry.


Assuntos
Aprendizado de Máquina , Animais , China , Espectrometria de Massas/métodos , Lasers , Alimentos Marinhos/análise , Peixes/classificação , Geografia
8.
Front Cardiovasc Med ; 10: 1185890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600060

RESUMO

Background: Ischemic stroke (IS) is one of the most common serious secondary diseases of atrial fibrillation (AF) within 1 year after its occurrence, both of which have manifestations of ischemia and hypoxia of the small vessels in the early phase of the condition. The fundus is a collection of capillaries, while the retina responds differently to light of different wavelengths. Predicting the risk of IS occurring secondary to AF, based on subtle differences in fundus images of different wavelengths, is yet to be explored. This study was conducted to predict the risk of IS occurring secondary to AF based on multi-spectrum fundus images using deep learning. Methods: A total of 150 AF participants without suffering from IS within 1 year after discharge and 100 IS participants with persistent arrhythmia symptoms or a history of AF diagnosis in the last year (defined as patients who would develop IS within 1 year after AF, based on fundus pathological manifestations generally prior to symptoms of the brain) were recruited. Fundus images at 548, 605, and 810 nm wavelengths were collected. Three classical deep neural network (DNN) models (Inception V3, ResNet50, SE50) were trained. Sociodemographic and selected routine clinical data were obtained. Results: The accuracy of all DNNs with the single-spectral or multi-spectral combination images at the three wavelengths as input reached above 78%. The IS detection performance of DNNs with 605 nm spectral images as input was relatively more stable than with the other wavelengths. The multi-spectral combination models acquired a higher area under the curve (AUC) scores than the single-spectral models. Conclusions: The probability of IS secondary to AF could be predicted based on multi-spectrum fundus images using deep learning, and combinations of multi-spectrum images improved the performance of DNNs. Acquiring different spectral fundus images is advantageous for the early prevention of cardiovascular and cerebrovascular diseases. The method in this study is a beneficial preliminary and initiative exploration for diseases that are difficult to predict the onset time such as IS.

9.
Food Chem ; 429: 136986, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37516053

RESUMO

The illegal adulteration of non-dairy cream in milk fat cream during the manufacturing process of baked goods has significantly hindered the robust growth of the dairy industry. In this study, a method based on rapid evaporative ionization mass spectrometry (REIMS) lipidomics pattern recognition integrated with machine learning algorithms was established. A total of 26 ions with importance were picked using multivariate statistical analysis as salient contributing features to distinguish between milk fat cream and non-dairy cream. Furthermore, employing discriminant analysis, decision trees, support vector machines, and neural network classifiers, machine learning models were utilized to classify non-dairy cream, milk fat cream, and minute quantities of non-dairy cream adulterated in milk fat cream. These approaches were enhanced through hyperparameter optimization and feature engineering, yielding accuracy rates at 98.4-99.6%. This artificial intelligent method of machine learning-guided REIMS pattern recognition can accurately identify adulteration of whipped cream and might help combat food fraud.


Assuntos
Aprendizado de Máquina , Leite , Animais , Leite/química , Espectrometria de Massas , Algoritmos , Análise Discriminante
10.
J Agric Food Chem ; 71(20): 7937-7946, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37166010

RESUMO

Comprehensive screening for functional substances from natural resources is always a hot research topic. Eicosapentaenoic acid- (EPA) and docosahexaenoic acid (DHA)-structured phospholipids (PLEPA/DHA) have versatile cardiovascular benefits as well as superior bioavailability. Herein, the abundance of PLEPA/DHA in 16 aquatic products was specifically and selectively screened using a recently developed precursor ion scan-driven hydrophilic interaction chromatography-mass spectrometry (PreIS-HILIC/MS) method with the fatty acyl moieties of EPA (m/z 301.6) and DHA (m/z 327.6) locked. The aim focused on the characteristics and differences in the varieties and contents of EPA/DHA-structured phosphatidylcholine (PCEPA/DHA) and EPA/DHA-structured phosphatidylethanolamine (PEEPA/DHA) molecular species. A total of 80 PLEPA/DHA molecules were identified in these natural sources, including 47 PCEPA/DHA and 33 PEEPA/DHA. After analysis, PC 16:0/20:5 and PC 16:0/22:6 are present in all aquatic products and at high levels. Antarctic krill was found to be the best resource of PLEPA/DHA in total (2574.69 µg·g-1), followed by mackerel (2330.11 µg·g-1), salmon (2109.91 µg·g-1), and Farrer's scallop (1883.59 µg·g-1), while abalone contained the lowest level of PLEPA/DHA (310.44 µg·g-1). Besides, sea cucumber and sea bass contained the highest contents of EPA-structured and DHA-structured ether phospholipids, respectively, which could be highly recommended as dietary sources of special functional phospholipids. Finally, the multiple discrepancies between the 16 aquatic products were revealed by multivariate statistical analysis. These findings improve the awareness of the composition and content of PLEPA/DHA contained in aquatic products, providing a reference for their integrated development.


Assuntos
Ácido Eicosapentaenoico , Fosfolipídeos , Ácido Eicosapentaenoico/química , Fosfolipídeos/química , Ácidos Docosa-Hexaenoicos , Espectrometria de Massas em Tandem , Lecitinas
11.
Food Res Int ; 156: 111307, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35651067

RESUMO

As a high-value processed aquatic product, wet-aged tuna has gradually become a popular food, but its lipidomics characteristics during the aging process have not been investigated. Herein, the lipidomics phenotypic data of tuna at different wet-aging stages were acquired using iKnife rapid evaporative ionization mass spectrometry, in which the dominant lipid components, including fatty acid (FA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylinositol (PI), were structurally identified. Principal component analysis, permutation test, heatmap, and circos plot analysis were performed to characterize lipids in wet-aged tuna, among which FAC18:1, docosahexaenoic acid (DHA), and PIC18:0/22:6 were the most contributing components for determining the wet-aging stage of tuna. The results indicated that iKnife-REIMS is accurate (86.5%), reliable, and could be used in the real-time detection of tuna meat during different wet-aging stages.


Assuntos
Lipidômica , Atum , Animais , Ácidos Graxos , Espectrometria de Massas/métodos , Carne/análise
12.
Front Nutr ; 9: 1034868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386960

RESUMO

Trichiurus lepturus (hairtail) is an important economic component of China's marine fishing industry. However, due to the difficulty in identifying the appearance of hairtail from different geographical distributions, hairtails with geographical indication trademarks were imitated by general varieties. In this study, the texture characteristics, color, basic nutrients, amino acids, mineral, fatty acids, and volatile flavor substances were used as indicators for multivariate statistical analysis to determine whether three origins of hairtails from the habitats of Zhoushan (East China Sea, T.Z), Hainan (South China Sea, T.N), and Qingdao (Yellow Sea, T.Q) in the market could be distinguished. The findings revealed that there were significant differences in amino acids composition, mineral composition, fatty acid composition in lipids, and volatile flavor substances among the hairtails of three origins (P < 0.05), but no differences in color, texture, protein content. T.Z had moisture, crude fat, essential amino acids (EAA), flavor amino acids (FAA), unsaturated fatty acids (UFA), and docosahexaenoic acids and dicosapentaenoic acids (ΣEPA + DHA) contents of 74.33, 5.4%, 58.25 mg⋅g-1, 46.20 mg⋅g-1, 66.84 and 19.38%, respectively, and the contents of volatile alcohols, aldehydes and ketones were 7.44, 5.30, and 5.38%, respectively. T.N contains moisture, crude fat, EAA, FAA, UFA and ΣEPA + DHA as 77.69, 2.38%, 64.76 mg⋅g-1, 52.44 mg⋅g-1, 65.52 and 29.45%, respectively, and the contents of volatile alcohols, aldehydes and ketones as 3.21, 8.92, and 10.98%, respectively. T.Q had the contents of moisture, crude fat, EAA, FAA, UFA, and ΣEPA + DHA 79.69, 1.43%, 60.9 mg⋅g-1, and 49.42 mg⋅g-1, respectively. The contents of unsaturated fatty acid and ΣEPA + DHA were 63.75 and 26.12%, respectively, while the volatile alcohols, aldehydes, and ketones were 5.14, 5.99, and 7.85%, respectively. Partial least squares-discriminant analysis (PLS-DA) multivariate statistical analysis showed that volatile flavor compounds could be used as the most ideal indicators for tracing the source of hairtail. In conclusion, the findings of this study can distinguish the three hairtail origins using some basic indicators, providing ideas for hairtail geographical identification.

13.
J Agric Food Chem ; 70(25): 7786-7795, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35696488

RESUMO

The price of mammalian milk from different animal species varies greatly due to differences in their yield and nutritional value. Therefore, the authenticity of dairy products has become a hotspot issue in the market due to the replacement or partial admixture of high-cost milk with its low-cost analog. Herein, four common commercial varieties of milk, including goat milk, buffalo milk, Holstein cow milk, and Jersey cow milk, were successfully profiled and differentiated from each other by rapid evaporative ionization mass spectrometry (REIMS) combined with chemometric analysis. This method was developed as a real-time lipid fingerprinting technique. Moreover, the established chemometric algorithms based on multivariate statistical methods mainly involved principal component analysis, orthogonal partial least squares-discriminant analysis, and linear discriminant analysis as the screening and verifying tools to provide insights into the distinctive molecules constituting the four varieties of milk. The ions with m/z 229.1800, 243.1976, 257.2112, 285.2443, 299.2596, 313.2746, 341.3057, 355.2863, 383.3174, 411.3488, 439.3822, 551.5051, 577.5200, 628.5547, 656.5884, 661.5455, 682.6015, and 684.6146 were selected as potential classified markers. The results of the present work suggest that the proposed method could serve as a reference for recognizing dairy fraudulence related to animal species and expand the application field of REIMS technology.


Assuntos
Quimiometria , Leite , Animais , Bovinos , Análise Discriminante , Feminino , Lipídeos/análise , Mamíferos , Espectrometria de Massas/métodos , Leite/química
14.
Food Chem ; 383: 132432, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35182874

RESUMO

Minced shrimp is popular seafood due to its delicious flavor and nutritional value. However, the biological species of raw material of minced shrimp are not distinguished by naked eyes after processing. Thus, an in situ and real-time minced shrimp authentication method was established using iKnife rapid evaporative ionization mass spectrometry (REIMS) based lipidomics. The samples were analyzed under ambient ionization without any tedious preparation step. Seven economic shrimp samples were tested, whose phenotypes were used to develop a real-time recognition model. A total of 19 fatty acids and 45 phospholipid molecular species were efficiently identified and statistically analyzed by multivariate statistical analysis. The results showed that the seven shrimp species were well distinguished, and the most contributing ions at m/z 255.2, 279.2, 301.2, 327.2, 699.5, 742.5, etc., were revealed by variable importance in projection. The proposed iKnife REIMS showed excellent performance in minced shrimp authentication.


Assuntos
Lipidômica , Alimentos Marinhos , Animais , Crustáceos , Ácidos Graxos/química , Espectrometria de Massas/métodos , Fosfolipídeos/química , Alimentos Marinhos/análise
15.
Food Chem ; 347: 129011, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482489

RESUMO

In this study, a steam explosion pretreatment method was established to prepare tuna bone powder. The conditions were optimized such that steam pressure of 0.6 MPa, reaction time of 5 min, and sample weight of 100 g. The result showed that steam explosion pretreatment would not change the chemical structure of bone powder, however, the median particle size (D50) of the steam explosion pretreated tuna bone powder (SE-TBP) (13.186 µm) was significantly smaller than that of normal biological calcium tuna bone powder (N-TBP) (169.762 µm). The calcium absorption rate (79.75 ± 2.33%) and utilization rate (78.75% ± 2.85%) of the mice fed with SE-TBP were both higher than those of fed with CaCO3 or N-TBP with the same calcium equivalent in the feed. The steam explosion pretreatment method could obtain ideal tuna bone powder in a shorter time, provide a method for deep processing and utilization of tuna bone by-product.


Assuntos
Osso e Ossos/química , Cálcio da Dieta/farmacocinética , Produtos Pesqueiros/análise , Manipulação de Alimentos/métodos , Vapor , Atum , Animais , Disponibilidade Biológica , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula
16.
RSC Adv ; 9(60): 35189-35196, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35530677

RESUMO

Efficient C-ZnS/ZnMoO4@MoS2 and C-ZnS/MoS2 nanocomposite photocatalysts, using ZIF-8 derived C-ZnO as a precursor were successfully synthesized using a simple one-pot procedure. This is the first application that involves transforming ZIF-8 into C-ZnMoO4 for photocatalysis. The C-ZnS/ZnMoO4@MoS2 and C-ZnS/MoS2 heterostructures were characterized by X-ray diffraction, UV-vis, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, photocurrent measurements, scanning electron microscopy and transmission electron microscopy. The ZM2 sample of C-ZnS/ZnMoO4@MoS2 exhibited enhanced photocatalytic activity of about 2.9 times as high as that of ZIF-8 derived C-ZnO in the reduction of tetracycline hydrochloride, and also showed obvious photocatalytic activity 1.81 and 3.33 times as high as that of a ZM3 sample of C-ZnS/MoS2 and ZIF-8 derived C-ZnO in the degradation of RhB, respectively. The improved photodegradation activity is a result of the heterogenous structure and the tighter contact between C-ZnS and C-ZnMoO4 compared with the physical contact of general heterogenous photocatalysts. The C-ZnS/ZnMoO4@MoS2 heterostructure photocatalyst is expected to be a new type of nanomaterial for the degradation of pollutants from wastewater.

17.
RSC Adv ; 9(22): 12689-12695, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-35515824

RESUMO

Recently, engineering metal-organic frameworks (MOFs) into metal oxides by solid state thermal decomposition has attracted wide attention for photocatalytic applications. Here, a series of C-doped ZnO materials decorated with Au nanoparticles (Au/C-ZnO) were constructed via controlled pyrolysis of ZIF-8 adsorbing different amounts of HAuCl4·4H2O. In this pyrolysis process, ZIF-8 was transformed into C-doped ZnO according to the EDX and XPS analysis. Meanwhile, HAuCl4·4H2O was transformed into Au nanoparticles that were uniformly dispersed on the surface of C-ZnO as seen in TEM images. The photocatalytic activity of as-prepared catalysts was evaluated by the degradation of methyl orange under UV-vis light irradiation. It was found that the photocatalytic activity of Au/C-ZnO was better than C-ZnO and pure ZnO. Furthermore, Au/C-ZnO exhibited high photocatalytic stability. After three consecutive cycles, there was no noticeable deactivation in the reaction. This unusual photocatalytic activity was attributed to the synergistic effect of C-doping and Au NPs.

18.
Biomed Environ Sci ; 21(1): 75-84, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18478982

RESUMO

OBJECTIVE: To investigate the social mental state of drug addicts in a compulsive drug abuse treatment center; evaluate the effectiveness of integrated program for the prevention of abuse relapse and improvement of drug addicts' psychological health. METHODS: The study subjects were addicts from the Wuhan Compulsive Drug Abuse Treatment Center between October 2003 and June 2004, who satisfied the inclusion criteria. A non-randomized control-intervention study design was adopted. Volunteers willing to take part in intervention were put into the intervention group with their full awareness and willingness to prevent drug abuse relapse. The control group was composed of the addicts who were willing to prevent relapse and to be followed up after their discharge. RESULTS: The effectiveness of the integrated intervention program in promoting addicts' psychological health: before the intervention, the scores of Self-Rating Anxiety Scale (SAS), the positive and negative dimensionalities of Simple Coping Style Questionnaire (SCSQ) and Chinese Perceived Stress Scales (CPSS) had no significant differences between the intervention group and the control group. After the intervention, except that the SCSQ's positive dimensionality in the intervention group was significantly higher than that in the control group, other indices in the intervention group were lower. Before and after the intervention, the psychological health level in both the groups was lower than that in the normal population; there were significant differences between addicts and normal subjects in regards with all of the indices above. CONCLUSION: Drug abuse was associated closely with addicts' social mental factors. The integrated intervention program can alleviate anxiety and stress, reduce co-morbid mental disorders and effectively improve their coping style. In conclusion, the program can promote addicts' psychological health significantly.


Assuntos
Saúde Mental , Transtornos Relacionados ao Uso de Substâncias/terapia , Adaptação Psicológica , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Estresse Psicológico , Transtornos Relacionados ao Uso de Substâncias/psicologia
19.
Food Chem ; 269: 89-95, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100488

RESUMO

A selective and sensitive procedure for determining seven hazardous microcystins in Margarya melanioides, using tandem mass spectrometry, is presented. The product ion m/z 135.2 was selected as representative for precursor ion scanning and used to increase overall sensitivity of this shotgun method. The method was validated, and recoveries ranged from 69.3 to 87.9%, with the relative standard deviation less than 10%. Limits of detection and quantitation were less than 3.1 and 9.3 ng·mL-1, respectively. A total of 60 samples were tested using this method. 38 samples were found to be contaminated with microcystins, among which there are 31 samples whose estimated daily intake (EDI) was 0-7.8 times higher than the tolerable daily intake (TDI). This method would be useful for carrying out direct, ultra-rapid quantification of microcystins in foods, and is of significant interest for environmental and food safety applications.


Assuntos
Gastrópodes/química , Microcistinas/análise , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão , Gastrópodes/metabolismo , Microcistinas/metabolismo
20.
J Agric Food Chem ; 66(24): 6246-6253, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29806465

RESUMO

A rapid evaporative ionization mass spectrometry (REIMS) method was developed for lipidomics tracking of Ctenopharyngodon idellus during in vitro multiple-stage digestion. The REIMS conditions were optimized such that the temperature of the heating probe was 500 °C, sample amount was 30 mg, and the flow rate of auxiliary solvent was 100 µL min-1. The results showed that the phospholipids were detected with variety and quantity in the crude and multiple-stage digested samples. The enzymatic effect on the phospholipids is varied depending on the phospholipid classes, and the hydrolysis rate of phospholipids increased as the degree of unsaturation of the acyl chain increased. The principal component analysis (PCA) indicated that the ions at m/ z 809.61, 811.63, and 857.52 were the most noticeable species digested during the process. This method exhibited great potential in fast lipidomics profiling for inspecting the characteristics of nutritional lipid absorption digestion in human gastrointestin.


Assuntos
Carpas/metabolismo , Digestão , Fosfolipídeos/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Fosfolipídeos/química , Alimentos Marinhos/análise , Temperatura
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