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1.
Foods ; 13(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38790766

RESUMO

BACKGROUND: Metabolic changes in donkey meat during the early postmortem period have not been previously reported. METHODS: The LC-MS-based metabolomics technique was conducted to understand the metabolic profiles and identify the key metabolites of donkey meat in the first 48 h postmortem. RESULTS: The pH values showed a decreasing trend followed by an increasing trend. Shear force was the lowest at 4 h and the highest at 24 h (p < 0.05). For the metabolome, some candidate biomarker metabolites were identified, such as adenine, inosine, n-acetylhistidine, citric acid, isocitrate, and malic acid. Predominant metabolic pathways, such as citrate cycle (TCA cycle), alanine, aspartate and glutamate metabolism, and purine metabolism, were affected by aging time. Overabundant n-acetylhistidine was identified in LT, declined at 12 h postmortem aging, and then increased. This may explain the significantly lower pH at 12 h postmortem. Adenine was higher at 4 h postmortem, then declined. Decreased ADP may indicate a fast consumption of ATP and subsequent purine metabolism in donkey meat. CONCLUSIONS: The results of this study provided new insights into early postmortem aging of donkey meat quality.

2.
Int J Biol Macromol ; 253(Pt 7): 127076, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37769780

RESUMO

Biodegradable, biomass derived kombucha cellulose films with increased mechanical strength from 9.98 MPa to 18.18 MPa were prepared by vortex fluidic device (VFD) processing. VFD processing not only reduced the particle size of kombucha cellulose from approximate 2 µm to 1 µm, but also reshaped its structure from irregular to round. The increased mechanical strength of these polysaccharide-derived films is the result of intensive micromixing and high shear stress of a liquid thin film in a VFD. This arises from the incorporation at the micro-structural level of uniform, unidirectional strings of kombucha cellulose hydrolysates, which resulted from the topological fluid flow in the VFD. The biodegradability of the VFD generated polymer films was not compromised relative to traditionally generated films. Both films were biodegraded within 5 days.


Assuntos
Alginatos , Celulose , Ágar/química , Celulose/química , Biomassa , Fenômenos Físicos
3.
Tob Induc Dis ; 21: 104, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581174

RESUMO

INTRODUCTION: The widespread popularity of e-cigarettes is considered an important public health concern. However, only some studies have investigated the prevalence of e-cigarette use in Shanghai, China. Research on the perceived harmfulness of e-cigarettes and public support for e-cigarette regulations in China is limited. This study aimed to estimate e-cigarette awareness, prevalence, and associated factors among adults in Shanghai, China. METHODS: This study used data from a representative survey conducted in Shanghai, China, in 2019. The survey was conducted at 64 surveillance points in Shanghai, China, using a multistage, stratified, cluster-randomized sampling design, recruiting community-based Chinese adults aged ≥15 years. Based on the principles outlined in the Global Adult Tobacco Survey (GATS) China Project, data were collected by conducting face-to-face interviews in households. Of the 3200 selected households, 3060 people completed the individual survey. The overall response rate was 97.4%. RESULTS: In all, 72.3% of the respondents had heard of e-cigarettes. The respondents who had used e-cigarettes at some point in their life, used them in the last 12 months, and used them currently were 5.8%, 2.6%, and 1.3%, respectively. Among adult residents who had heard of e-cigarettes, 38.2% thought they were less harmful than traditional cigarettes. The respondents who perceived e-cigarettes as more harmful than traditional cigarettes were less likely to have ever used e-cigarettes (AOR=0.2; 95% CI: 0.1-0.5, p=0.0015) and more likely to support incorporating e-cigarettes into the regulation of smoking control (AOR=3.9; 95% CI: 1.8-8.6, p=0.0008). CONCLUSIONS: Our findings reveal that the awareness about e-cigarettes was high, and the prevalence of e-cigarette use was similar to the findings from previous studies in China. The harmful perception of e-cigarettes warrants further attention from public health practitioners.

4.
Biosensors (Basel) ; 13(6)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37366944

RESUMO

There is a constant need to maintain the quality of consumed food. In retrospect to the recent pandemic and other food-related problems, scientists have focused on the numbers of microorganisms that are present in different food items. As a result of changes in certain environmental factors such as temperature and humidity, there is a constant risk for the growth of harmful microorganisms, such as bacteria and fungi, in consumed food. This questions the edibility of the food items, and constant monitoring to avoid food poisoning-related diseases is required. Among the different nanomaterials used to develop sensors to detect microorganisms, graphene has been one of the primary materials due to its exceptional electromechanical properties. Graphene sensors are able to detect microorganisms in both a composite and non-composite manner, due to their excellent electrochemical characteristics such as their high aspect ratios, excellent charge transfer capacity and high electron mobility. The paper depicts the fabrication of some of these graphene-based sensors, and their utilization to detect bacteria, fungi and other microorganisms that are present in very small amounts in different food items. In addition to the classified manner of the graphene-based sensors, this paper also depicts some of the challenges that exist in current scenarios, and their possible remedies.


Assuntos
Técnicas Biossensoriais , Grafite , Nanoestruturas , Grafite/química , Técnicas Biossensoriais/métodos , Nanoestruturas/química
5.
Front Chem ; 11: 1044953, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846852

RESUMO

Breast cancer is the second most common cancer around the world. Triple-negative breast cancer (TNBC) is characterized by the absence of three receptors: progesterone, estrogen, and human epidermal growth factor-2 receptor (HER2). Various synthetic chemotherapies have gained attention but they caused unwanted side effects. Therefore, some secondary therapies are now becoming famous against this disease. For instance, natural compounds have been extensively researched against many diseases. However, enzymatic degradation and low solubility remain a major concern. To combat these issues, various nanoparticles have been synthesized and optimized from time to time, which increases its solubility and hence therapeutic potential of a particular drug increases. In this study, we have synthesized Poly D,L-lactic-co-glycolic acid (PLGA) loaded thymoquinone (TQ) nanoparticle (PLGA-TQ-NPs) and then coated them by chitosan (CS) (PLGA-CS-TQ-NPs), which was characterized by different methods. Size of non-coated NPs was 105 nm with PDI value of 0.3 and the size of coated NPs was 125 nm with PDI value of 0.4. Encapsulation efficiency (EE%) and Drug loading (DL%) was found to be 70.5 ± 2.33 and 3.38 for non-coated and 82.3 ± 3.11 and 2.66 for coated NPs respectively. We have also analysed their cell viability against MDA-MB-231 and SUM-149 TNBC cell lines. The resultant, nanoformulations exhibit anti-cancerous activity in a dose and time-dependent manner for MDA-MB-231 and SUM-149 cell lines with an IC50 value of (10.31 ± 1.15, 15.60 ± 1.25, 28.01 ± 1.24) and (23.54 ± 1.24, 22.37 ± 1.25, 35 ± 1.27) for TQ free, PLGA-TQ-NPs and PLGA-CS-TQ-NPs respectively. For the first time, we have developed a nanoformulations of PLGA loaded TQ coated with CS NPs (PLGA-CS-TQ-NPs) against TNBC which led to their enhanced anti-cancerous effects.

6.
J Sci Food Agric ; 103(8): 4157-4163, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36594434

RESUMO

BACKGROUND: The processing of sweet potatoes generates a waste by-product rich in sweet potato protein (SPP). OBJECTIVE: In this study, the effects of the concentrations of Alcalase and Ficin, hydrolysis time and pH value on the foaming properties of SPP hydrolysates (SPPHs) determined via gas sparging method were investigated. RESULTS: The results showed that SPPH prepared by Alcalase exhibited a significantly higher foaming expansion (the highest of 576%) than that of the SPP (462%) but displayed a weaker liquid volume stability compared with SPPH hydrolyzed by Ficin. The molecular weight of SPPH prepared by Alcalase was distributed in 10-30 kDa. A good microbiological quality of the SPPH prepared by Alcalase in pH 13 has been confirmed, and it is suitable for food application with respect to its microbiological safety profile. CONCLUSIONS: SPPH (pH 13) could be further safely applied in food, especially as a food additive at low concentrations to create a better organic plant-based foaming agent for the food industry. © 2023 Society of Chemical Industry.


Assuntos
Ipomoea batatas , Hidrolisados de Proteína , Hidrolisados de Proteína/química , Ficina , Ipomoea batatas/metabolismo , Subtilisinas/química , Hidrólise
7.
Nanomaterials (Basel) ; 12(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36234412

RESUMO

The advent of nanotechnology has initiated a profound revolution in almost all spheres of technology. The electronics industry is concerned with the ongoing miniaturization of devices and as such requires packaging technologies that will make the devices more compact and resilient. 3D packaging, system in package, and system on chip are the various packaging techniques that utilize nanoscale components for their implementation. The active components of the ICs have kept pace with Moore's law, but the passive components have proven an impediment in the race for miniaturization. Moreover, the toxic effects and nano-scale problems associated with conventional soldering techniques have entailed the active involvement of nanotechnology in the search for answers. Recent advances in these fields and the diverse nanomaterials which are being employed to resolve these issues have been discussed in detail.

8.
J Agric Food Chem ; 70(17): 5396-5407, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35452224

RESUMO

N-l-Lactoyl phenylalanine (N-l-lactoyl-Phe) has been identified as a taste-active contributor in many fermented foods. However, its preparation, taste property, and content in foodstuffs are little known to date. In the current study, two preparation technologies of N-l-lactoyl-Phe including heating and enzymatic methods were investigated. Other investigations include its taste property and quantification in several fermented foods. The results indicated that the heating preparation and enzymatic preparation only produced N-l-lactoyl-Phe instead of N-d-lactoyl-Phe in the presence of l-lactate/d-lactate and l-phenylalanine (Phe). A high yield (58.0% ± 0.7%) of N-l-lactoyl-Phe was achieved under the following conditions: Phe, lactate, CaO, and water at molar ratios of 1:8:0.3:9 kept at 100 °C for 3 h. With nine enzymes, a maximum yield of 21.2% ± 0.3% was achieved in the aqueous solution under mild operating conditions: 0.18 M Phe, 0.90 M lactate, 5 g/L Debitrase HYW 20, pH 8, and 55 °C for 24 h. The sensory evaluation revealed that N-l-lactoyl-Phe in water enhanced the salty and umami intensity. It also enhanced the thickness, mouthfulness, and continuity of salt solution, model broth, and chicken broth, revealing that N-l-lactoyl-Phe was a kokumi-active compound. The kokumi thresholds of N-l-lactoyl-Phe in these solutions were 50, 50, and 25 mg/L, respectively. N-l-Lactoyl-Phe was quantified in traditional Chinese fermented foods as 30.12 ± 0.28 mg/kg in preserved pickles, 14.11 ± 0.14 mg/kg in soybean paste, 4.87 ± 0.16 mg/kg in fermented bean, 0.71 ± 0.11 mg/kg in rice vinegar, and 20.34 ± 0.18 mg/kg in soy sauce. These results revealed the potential of N-l-lactoyl-Phe as a taste enhancer, presenting a new opportunity for the food industry.


Assuntos
Alimentos de Soja , Paladar , Ácido Láctico , Fenilalanina , Água
9.
Nanomaterials (Basel) ; 12(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35335764

RESUMO

This paper presents a substantial review of the fabrication and implementation of graphene-PDMS-based composites for wearable sensing applications. Graphene is a pivotal nanomaterial which is increasingly being used to develop multifunctional sensors due to their enhanced electrical, mechanical, and thermal characteristics. It has been able to generate devices with excellent performances in terms of sensitivity and longevity. Among the polymers, polydimethylsiloxane (PDMS) has been one of the most common ones that has been used in biomedical applications. Certain attributes, such as biocompatibility and the hydrophobic nature of PDMS, have led the researchers to conjugate it in graphene sensors as substrates or a polymer matrix. The use of these graphene/PDMS-based sensors for wearable sensing applications has been highlighted here. Different kinds of electrochemical and strain-sensing applications have been carried out to detect the physiological signals and parameters of the human body. These prototypes have been classified based on the physical nature of graphene used to formulate the sensors. Finally, the current challenges and future perspectives of these graphene/PDMS-based wearable sensors are explained in the final part of the paper.

10.
Sensors (Basel) ; 21(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064254

RESUMO

This paper presents a comprehensive review of the detection of aflatoxin compounds using carbon allotrope-based sensors. Although aflatoxin M1 and its derivative aflatoxin B1 compounds have been primarily found in milk and other food products, their presence above a threshold concentration causes disastrous health-related anomalies in human beings, such as growth impairment, underweight and even carcinogenic and immunosuppressive effects. Among the many sensors developed to detect the presence of these compounds, the employment of certain carbon allotropes, such as carbon nanotubes (CNTs) and graphene, has been highly preferred due to their enhanced electromechanical properties. These conductive nanomaterials have shown excellent quantitative performance in terms of sensitivity and selectivity for the chosen aflatoxin compounds. This paper elucidates some of the significant examples of the CNTs and graphene-based sensors measuring Aflatoxin M1 (ATM1) and Aflatoxin B1 (AFB1) compounds at low concentrations. The fabrication technique and performance of each of the sensors are shown here, as well as some of the challenges existing with the current sensors.


Assuntos
Grafite , Nanotubos de Carbono , Aflatoxina B1/análise , Aflatoxina M1/análise , Animais , Contaminação de Alimentos/análise , Humanos , Leite/química
11.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923790

RESUMO

This paper deals with recent progress in the use of laser-induced graphene sensors for the electrochemical detection of glucose molecules. The exponential increase in the exploitation of the laser induction technique to generate porous graphene from polymeric and other naturally occurring materials has provided a podium for researchers to fabricate flexible sensors with high dynamicity. These sensors have been employed largely for electrochemical applications due to their distinct advantages like high customization in their structural dimensions, enhanced characteristics and easy roll-to-roll production. These laser-induced graphene (LIG)-based sensors have been employed for a wide range of sensorial applications, including detection of ions at varying concentrations. Among the many pivotal electrochemical uses in the biomedical sector, the use of these prototypes to monitor the concentration of glucose molecules is constantly increasing due to the essentiality of the presence of these molecules at specific concentrations in the human body. This paper shows a categorical classification of the various uses of these sensors based on the type of materials involved in the fabrication of sensors. The first category constitutes examples where the electrodes have been functionalized with various forms of copper and other types of metallic nanomaterials. The second category includes other miscellaneous forms where the use of both pure and composite forms of LIG-based sensors has been shown. Finally, the paper concludes with some of the possible measures that can be taken to enhance the use of this technique to generate optimized sensing prototypes for a wider range of applications.


Assuntos
Técnicas Biossensoriais , Grafite , Técnicas Eletroquímicas , Glucose , Humanos , Lasers
12.
J Food Sci ; 85(6): 1699-1706, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32458467

RESUMO

The eight biogenic amines (BA), which are histamine (HIS), tryptamine, putrescine, 2-phenylethylamine, cadaverine, tyramine, spermidine, and spermine, were determined in Chub Mackerel under different storage conditions after being freshly caught. The storage time and temperature were varied and the guts either present or removed. This study describes a reverse-phase high-performance liquid chromatography (HPLC) with a fluorescence detector following precolumn derivation with dansyl chloride method for the determination of BA in in Chub Mackerel samples. HIS represented the highest content of BA regardless of the storage temperature and time. During a 24-hr period, the content of HIS reached its highest level of 6,466.63 mg/kg at the storage temperature of 30 °C, whereas it only reached 28.73 mg/kg in 24 hr when the storage temperature was 0 °C, which is way below the standard acceptable threshold level (400 mg/kg). The storage times for the content of HIS to exceed the standard threshold level for HIS at different storage temperatures of 0, 4, 10, 15, 20, and 25 °C were 12, 5, 4 days, 48, 36, 15, and 14 hr, respectively. However, these times were significantly shortened when the viscera was removed from freshly-caught fish before storage. This study not only provides data for monitoring the content of BA, especially HIS, to ensure the safe storage and consumption of freshly-caught Chub Mackerel, but also presents a cost-effective method to extend the storage time of freshly-caught Chub Mackerel. PRACTICAL APPLICATION: This study not only provides data for monitoring the content of BA, especially HIS, to ensure the safe storage and consumption of freshly-caught Chub Mackerel, but also presents a cost-effective method, which is gut-removal during storage, to extend the storage time of freshly-caught Chub Mackerel.


Assuntos
Aminas Biogênicas/análise , Armazenamento de Alimentos/métodos , Carne/análise , Animais , Cadaverina/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa , Histamina/análise , Perciformes
13.
China CDC Wkly ; 2(22): 399-403, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34594666

RESUMO

WHAT IS ALREADY KNOWN ON THIS TOPIC?: The average secondhand smoke exposure rate was 68.1% in China in 2018. The World Health Organization suggests that legislation must be used to achieve a 100% smoke-free environment and protect nonsmokers from secondhand smoke. WHAT IS ADDED BY THIS REPORT?: This study showed that the implementation of the Amendment Regulations on Smoking Control in Public Places of Shanghai had a significant effect on reducing the exposure rate of secondhand smoke. The rate in 2018 was 46.7%, which was significantly lower than that (58.5%) before implementation in 2016. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Considering the high exposure and the harm of secondhand smoke in China, it is necessary to promote smoke-free legislation and enforce tobacco control measures.

14.
Foods ; 8(12)2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817474

RESUMO

Muffins are popular bakery products. However, they generally contain high amounts of sugar. The over-consumption of muffins may therefore result in a high calorie intake and could lead to increased health risks. For this reason, muffins were prepared substituting sucrose with two levels of a base of stevia (Stevianna®). In addition, cocoa powder and vanilla were added to the muffin formulation with and without Stevianna® to mask any potential off flavors. Results illustrate that muffins with 50% Stevianna® replacement of sucrose were similar to the control samples in terms of volume, density and texture. However, replacement of sugar with 100% Stevianna® resulted in reductions in height (from 41 to 28 mm), volume (from 63 to 51 mL), and increased firmness (by four-fold) compared to the control sample. Sugar replacement significantly reduced the in vitro predictive glycemic response of muffins (by up to 55% of the control sample). This work illustrates the importance of sugar in maintaining muffin structure as well as controlling the rate of glucose release during simulated digestions.

16.
Virus Res ; 128(1-2): 9-17, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17531344

RESUMO

The development of effective antiviral drugs against hepatitis C virus (HCV) continues to be needed, since neither vaccines nor broadly effective therapeutic agents are available. HCV RNA-dependent RNA polymerase (NS5B) is strictly required for viral replication and thus represents an attractive target. Here, aqueous extracts from five traditional Chinese medicines were tested for their ability to inhibit NS5B activity by reporter assays using cell-based NS5B activity detecting systems. Among them, aqueous extract from Fructus Ligustri Lucidi exhibited a promising result, dose-dependent inhibition of the luciferase activity, an indicator of intracellular NS5B activity (p<0.001), in the absence of cytotoxicity. Further Quantitative RT-PCR assays and Western blot analysis showed aqueous extract from Fructus Ligustri Lucidi inhibited intracellular NS5B-catalyzed RNA synthesis dose-dependently (p<0.001) without affecting intracellular NS5B expression. Subsequent in vitro NS5B assays revealed that this extract could directly inhibit NS5B activity. Taken together, these results indicated that Fructus Ligustri Lucidi might offer a promising source of antiviral drugs against HCV NS5B. Purification of the active compound(s) and antiviral effect are clearly required in the future.


Assuntos
Hepacivirus/efeitos dos fármacos , Medicina Tradicional Chinesa , Extratos Vegetais/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Proteínas não Estruturais Virais/antagonistas & inibidores , Linhagem Celular Tumoral , Hepacivirus/enzimologia , Humanos , Luciferases/efeitos dos fármacos , Luciferases/metabolismo , RNA Viral/biossíntese
17.
Virus Res ; 114(1-2): 23-34, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15992957

RESUMO

A novel coronavirus (CoV) has recently been identified as the aetiological agent of severe acute respiratory syndrome (SARS). Nucleocapsid (N) proteins of the Coronaviridae family have no discernable homology, but they share a common nucleolar-cytoplasmic distribution pattern. There are three putative nuclear localization signal (NLS) motifs present in the N. To determine the role of these putative NLSs in the intracellular localization of the SARS-CoV N, we performed a confocal microscopy analysis using rabbit anti-N antisera. In this report, we show that the wild type N was distributed mainly in the cytoplasm. The N-terminal of the N, which contains the NLS1 (aa38-44), was localized to the nucleus. The C-terminus of the N, which contains both NLS2 (aa257-265) and NLS3 (aa369-390) was localized to the cytoplasm and the nucleolus. Results derived from analysis of various deletion mutations show that the region containing amino acids 226-289 is able to mediate nucleolar localization. The deletion of two hydrophobic regions that flanked the NLS3 recovered its activity and localized to the nucleus. Furthermore, deletion of leucine rich region (220-LALLLLDRLNRL) resulted in the accumulation of N to the cytoplasm and nucleolus, and when fusing this peptide to EGFP localization was cytoplasmic, suggesting that the N may act as a shuttle protein. Differences in nuclear/nucleolar localization properties of N from other members of coronavirus family suggest a unique function for N, which may play an important role in the pathogenesis of SARS.


Assuntos
Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Sinais de Localização Nuclear , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Animais , Chlorocebus aethiops , Proteínas do Nucleocapsídeo de Coronavírus , Citometria de Fluxo , Deleção de Genes , Humanos , Microscopia Confocal , Proteínas do Nucleocapsídeo/genética , Coelhos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , Transfecção , Células Vero
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