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1.
Adv Healthc Mater ; 9(17): e2001023, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32729260

RESUMO

The pulse is a key biomedical signal containing various human physiological and pathological information highly related to cardiovascular diseases. Pulse signals are often collected from the radial artery based on Traditional Chinese Medicine, or by using flexible pressure sensors. However, the wrist wrapped with a flexible pressure sensor exhibits unstable signals under hand motion because of the concave surface of the wrist. By contrast, fingertips have a convex surface and therefore show great promises in stable and long-term pulse monitoring. Despite the promising potential, the fingertip pulse signal is weak, calling for highly sensitive detecting devices. Here, a highly sensitive and flexible iontronic pressure sensor with a linear sensitivity of 13.5 kPa-1 , a swift response, and remarkable stability over 5000 loading/unloading cycles is developed. This sensor enables stable and high-resolution detection of pulse waveform under both static condition and finger motion. Fingertip pulse waveforms from subjects of different genders, age, and health conditions are collected and analyzed, suggesting that fingertip pulse information is highly similar to that of the radial artery. This work justifies that fingertip is an ideal platform for pulse signals monitoring, which would be a competitive alternative to existing complex health monitoring systems.


Assuntos
Dedos , Pulso Arterial , Feminino , Frequência Cardíaca , Humanos , Masculino , Monitorização Fisiológica , Movimento (Física)
2.
Crit Rev Food Sci Nutr ; 58(5): 711-725, 2018 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27624057

RESUMO

In practice, food products tend to be contaminated with food-borne pathogens at a low inoculum level. However, the huge potential risk cannot be ignored because microbes may initiate high-speed growth suitable conditions during the food chain, such as transportation or storage. Thus, it is important to perform predictive modeling of microbial single cells. Several key aspects of microbial single-cell modeling are covered in this review. First, based on previous studies, the techniques of microbial single-cell data acquisition and growth data collection are presented in detail. In addition, the sources of microbial single-cell variability are also summarized. Due to model microbial growth, traditional deterministic mathematical models have been developed. However, most models fail to make accurate predictions at low cell numbers or at the single-cell level due to high cell-to-cell heterogeneity. Stochastic models have been a subject of great interest; and these models take into consideration the variability in microbial single-cell behavior.


Assuntos
Microbiologia de Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Modelos Biológicos , Análise de Célula Única
3.
Chem Commun (Camb) ; 53(59): 8376, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28702552

RESUMO

Correction for 'A new AIE multi-block polyurethane copolymer material for subcellular microfilament imaging in living cells' by Yu-qing Niu et al., Chem. Commun., 2017, DOI: .

5.
Int J Biol Macromol ; 102: 1195-1201, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28431945

RESUMO

A fucosylated chondroitin sulfate (FCS-pg) with highly repeated structure from Pearsonothuria graeffei was subjected to a in vitro fermentation model to investigate its fermentability and effects on human gut microflora. High performance liquid chromatography (HPLC) measurement found FCS-pg can be fermented to short chain fatty acids (SCFAs) by gut microflora from partial human fecal samples. 16S rRNA gene-based polymerase chain reaction-based denaturing gradient gel electrophoresis (PCR-DGGE) profiling and real-time quantitative PCR analysis showed that FCS-pg mainly increased the proportions of Clostridium cluster XI, Bacteriodes prevotella group, Bifidobacterium genus, Clostridium cluster I and Clostridium cluster XIVab, whereas the numbers of the Enterobacteriaceae and Lactobacillus decreased. These results indicated that FCS-pg was mainly fermented by Bacteroides, Bifidobacterium and Clostridium. It increased the content of probiotics bacteria in achieving health-enhancing effect, was slightly different than most sulfated polysaccharides from marine animals. The current study provides useful new information on the mechanism of absorption and functional activity on FCS-pg within the gastrointestinal tract of the human body.


Assuntos
Sulfatos de Condroitina/metabolismo , Fermentação , Microbioma Gastrointestinal , Pepinos-do-Mar/química , Animais , Humanos
6.
Mar Drugs ; 14(9)2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27657094

RESUMO

Fucosylated chondroitin sulfate (fCS) from sea cucumber Isostichopus badionotus (fCS-Ib) with a chondroitin sulfate type E (CSE) backbone and 2,4-O-sulfo fucose branches has shown excellent anticoagulant activity although has also show severe adverse effects. Depolymerization represents an effective method to diminish this polysaccharide's side effects. The present study reports a modified controlled Fenton system for degradation of fCS-Ib and the anticoagulant activity of the resulting fragments. Monosaccharides and nuclear magnetic resonance (NMR) analysis of the resulting fragments indicate that no significant chemical changes in the backbone of fCS-Ib and no loss of sulfate groups take place during depolymerization. A reduction in the molecular weight of fCS-Ib should result in a dramatic decrease in prolonging activated partial thromboplastin time and thrombin time. A decrease in the inhibition of thrombin (FIIa) by antithromin III (AT III) and heparin cofactor II (HCII), and the slight decrease of the inhibition of factor X activity, results in a significant increase of anti-factor Xa (FXa)/anti-FIIa activity ratio. The modified free-radical depolymerization method enables preparation of glycosaminoglycan (GAG) oligosaccharides suitable for investigation of clinical anticoagulant application.

7.
J Food Sci ; 81(3): E610-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26869019

RESUMO

Slightly acidic electrolyzed water (SAEW) has been recognized as an effective bactericidal agent with free chlorine, but its limitations include its instability and its great dependence on equipment. Newly developed circulating electrolyzed water (CEW) with a higher available chlorine concentration (ACC) could successfully overcome these limitations. In this study, SAEW (ACC of 20 mg/L), CEW1 (ACC of 200 mg/L), and CEW2 (ACC of 20 mg/L) were evaluated for changes in properties (pH, oxidization reduction potential [ORP], and ACC) during storage in open or closed glass bottles under light or dark conditions at room temperature (approximately 20 °C) and after washing pork and lettuce. Additionally, the washed pork and lettuce were evaluated for total viable counts, pH and general appearance. The results showed that CEW1 with a higher ACC has better stability than SAEW with a lower ACC for the storage and washing experiments, and CEW still remained stable after dilution with distilled water. The property indices of EW were greatly affected for the pork-washing experiments compared with the lettuce-washing experiments, probably due to the existence of alkaline and organic materials on the surface of pork. Furthermore, EWs were more effective for inactivating microbes in lettuce than in pork, while there was no significant difference in tissue pH and the general appearance of pork and lettuce. These findings indicated that CEW with a higher ACC shows potential for reducing foodborne pathogens on pork and lettuce without effects on their physicochemical characteristics, and it can be applied in a diluted form.


Assuntos
Cloro , Desinfetantes/química , Eletrólise , Microbiologia de Alimentos , Viabilidade Microbiana , Água/química , Animais , Cloro/análise , Cloro/farmacologia , Desinfetantes/farmacologia , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Lactuca/microbiologia , Carne/microbiologia , Suínos
8.
J Food Prot ; 79(1): 148-52, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26735042

RESUMO

The objectives of this study were to develop a probability model of Staphylococcus aureus enterotoxin A (SEA) production as affected by water activity (a(w)), pH, and temperature in broth and assess its applicability for milk. The probability of SEA production was assessed in tryptic soy broth using 24 combinations of a(w) (0.86 to 0.99), pH (5.0 to 7.0), and storage temperature (10 to 30°C). The observed probabilities were fitted with a logistic regression to develop a probability model. The model had a concordant value of 97.5% and concordant index of 0.98, indicating that the model satisfactorily describes the probability of SEA production. The model showed that a(w), pH, and temperature were significant factors affecting the probability of toxin production. The model predictions were in good agreement with the observed values obtained from milk. The model may help manufacturers in selecting product pH and a(w) and storage temperatures to prevent SEA production.


Assuntos
Enterotoxinas/biossíntese , Staphylococcus aureus/metabolismo , Água/fisiologia , Animais , Bovinos , Enterotoxinas/química , Modelos Logísticos , Leite/microbiologia , Staphylococcus aureus/química , Temperatura , Água/análise , Água/metabolismo
9.
Food Funct ; 5(1): 123-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24292561

RESUMO

Iron deficiency anemia (IDA) is the one of the most common nutritional problems and is encountered all over the world. This study analysed the effects of squid ink melanin-Fe (SM-Fe) on IDA in rats. Forty weanling SD male rats were used and thirty-two rats were fed an iron-deficient diet for 4 weeks. Then SM-Fe (dosages of iron is 6 mg kg(-1) BW) was given to the IDA rats once a day for 3 weeks by intragastric administration, with FeCl3 and FeSO4 (dosages of iron is 6 mg kg(-1) BW) as positive controls. While the IDA model group and the control group were administrated distilled deionized water each day for 3 weeks. The content of haemoglobin (Hb), serum iron (SI), total iron binding capacity (TIBC), serum ferritin (SF), transferrin receptor (sTfR), erythropoietin (EPO), and iron content in the liver and spleen were measured. The results showed that the content of Hb, SI, SF, EPO, iron content in the liver and spleen were significantly increased in the iron supplement groups (SM-Fe, FeCl3 and FeSO4) compared with the model group (P < 0.05), while TIBC and sTfR were significantly decreased in the iron supplement groups compared with the model group (P < 0.05). In comparison with the FeCl3 and FeSO4 groups, a higher bioavailability of iron and fewer side effects were observed in the SM-Fe group. The present study indicated that SM-Fe is an effective source of iron supplement for IDA rats and might be exploited as a new iron fortifier.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Ferro/sangue , Melaninas/administração & dosagem , Anemia Ferropriva/metabolismo , Animais , Decapodiformes , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Masculino , Melaninas/química , Ratos , Ratos Sprague-Dawley , Receptores da Transferrina/metabolismo
10.
ACS Appl Mater Interfaces ; 5(24): 12784-8, 2013 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-24283473

RESUMO

Detection of H2O2 is important for the applications in environmental protection, pharmaceutical industries, food production, and clinical control. Current colorimetric assay of H2O2 based on enzyme or nanomaterials always needs TMB or other peroxidase substrate as coloration species. Furthermore, the corresponding response time including incubation process is in order of minute. In this study, we report on the synthesis of heavily Ti(3+)-doped TiO2 composed of spherelike nanoparticles by pulsed laser ablation method. This TiO2 can directly detect H2O2 without using TMB or any other peroxidase substrate and is free from incubation process. In addition, the detection sensitivity is compatible with or better than that of the natural enzyme or other nanomaterials. Hence, the self-doped TiO2 nanoparticles provide a novel, direct, ultrafast approach for H2O2 assay application.


Assuntos
Colorimetria , Peróxido de Hidrogênio/análise , Titânio/química , Benzidinas/química , Benzidinas/metabolismo , Lasers , Nanopartículas Metálicas/química , Peroxidase/metabolismo
11.
J Agric Food Chem ; 56(13): 4937-42, 2008 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-18557622

RESUMO

A creative and sensitive method has been developed for the determination of triterpene glycosides concentrations in sea cucumber ( Stichopus japonicus) and related products by using d-quinovose (6-deoxyglucose) as the measurement standard by reverse-phase high-performance liquid chromatography (HPLC) and variable-wavelength detection. d-quinovose, which is a unique monosaccharide in holostane triterpene glycosides, was liberated by acid hydrolysis and precolumn derivatized by 1-phenyl-3-methyl-5-pyrazolone (PMP). PMP-quinovose was analyzed by HPLC with 22% acetonitrile in 0.05 M KH2PO4 aquatic solution (pH 5.2) as mobile phase. The calibration curves of d-quinovose were linear within the range of 6.56-164 mg/L (r(2) > 0.995). The contents of triterpene glycosides in various S. japonicus products were determined after appropriate pretreatment methods. The concentration of triterpene glycosides was calculated by the formula C = C(qui) x alpha (alpha = 8.5). The result showed that this method was a simple, rapid, and stable method for the determination of triterpene glycosides in S. japonicus products.


Assuntos
Glicosídeos/análise , Pepinos-do-Mar/química , Triterpenos/análise , Animais , Cromatografia Líquida de Alta Pressão , Pepinos-do-Mar/metabolismo , Alimentos Marinhos/análise , Manejo de Espécimes
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