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1.
Food Chem ; 339: 128078, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152871

RESUMO

The purpose of this work was to characterize the dynamic texture perception and study the mechanisms occurring in bolus from chewing to swallowing during white bread oral processing. Results indicated that the microstructural and chemical composition properties determined the oral processing behaviors. At the initial stage of oral processing, the roughness, hardness, and dryness perception were the dominant attributes. At the end of oral processing the adhesiveness and softness perception were dominant, which correlated to the higher bolus water content and adhesive properties. The softness and adhesiveness perception were the key factors that trigger swallowing. In vitro artificial mastication experiments confirmed that mucin rapidly increased the adhesive force of bolus at the initial stage of oral processing, whereas α-amylase gradually increased the adhesive force. These results can help to better understand the dynamic texture perception and its change mechanisms during oral processing.


Assuntos
Pão , Deglutição , Mastigação , Sensação , Adesividade , Dureza , Humanos , Triticum
2.
J Hazard Mater ; 402: 123720, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33254758

RESUMO

The potential risks of sono-induced nitrosation and nitration side reactions and consequent toxic nitrogenous byproducts were first investigated via sono-degradation of diphenylamine (DPhA) in this study. The kinetic models for overall DPhA degradation and the formation of nitrosation byproduct (N-nitrosodiphenylamine, NDPhA) and nitration byproducts (2-nitro-DPhA and 4-nitro-DPhA) were well established and fitted (R2 > 0.98). Nitrosation contributed much more than nitration (namely, 43.3 - 47.3 times) to the sono-degradation of DPhA. The contribution of sono-induced nitrosation ranged from 0.4 to 56.6% at different conditions. The maximum NDPhA formation rate and the contribution of sono-induced nitrosation were obtained at 600 and 200 kHz, respectively, as ultrasonic frequencies at 200 to 800 kHz. Both NDPhA formation rate and the contribution of sono-induced nitrosation increased with increasing power density, while decreased with increasing initial pH and DPhA concentration. PO43-, HCO3-, NH4+ and Fe2+ presented negative impacts on sono-induced nitrosation in order of HCO3- >> Fe2+ > PO43- > NH4+, while Br- exhibited a promoting effect. The mechanism of NDPhA formation via sono-induced nitrosation was first proposed.

3.
Ann Clin Lab Sci ; 50(6): 775-780, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33334793

RESUMO

OBJECTIVE: To investigate the relationship between Transient Receptor Potential Vanilloid 6 (TRPV6) and ST-elevation acute myocardial infarction (STEMI) patients. METHODS: This observational research included a total of 221 patients with STEMI admitted during January 2017~August 2019. Additionally, 50 cases of non-ST-elevation acute myocardial infarction (NSTEMI) patients and 50 healthy individuals were enrolled as the control. Serum levels of TRPV6 were detected by ELISA method. The relationship between TRPV6, clinical characteristics, laboratory indices of CK-MB, TnI, NT-pro-B-type natriuretic peptide (NT-pro-BNP), C-reactive protein (CRP), and the left ventricular ejection fraction (LVEF%) was analyzed by statistical methods. K-M curve was performed for survival time. RESULTS: Serum levels of TRPV6 were remarkably lower in STEMI and NSTEMI patients compared with the healthy control. Levels of NT-pro-BNP and CK-MB were significantly higher and serum levels of TRPV6 were dramatically lower in deceased STEMI patients in comparison with the surviving patients. The levels of TRPV6 were negatively correlated with CK-MB and NT-pro-BNP. Meanwhile, TRPV6 was negatively expressed in tissues of STEMI patients and positively expressed in normal tissues. Patients with lower TRPV6 levels had remarkably lower LVEF ratio, higher GRACE scores, higher CK-MB and NT-pro-BNP levels, as well as higher ratios of cardiovascular death, malignant arrhythmia, cumulative MACE, and shorter survival time than patients with higher TRPV6. CONCLUSION: The lower expression of TRPV6 was associated with poor clinical outcomes and prognosis of STEMI patients.

4.
Genomics ; 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33144217

RESUMO

DIRIGENT (DIR) genes play important roles in regulating plant growth and development and have been studied in many plant species. However, information on DIR genes in soybean is limited. Here, we identified and characterized 54 GmDIRs and studied the characteristics of GmDIRs. Most of the GmDIRs contained a classical gene structure, one exon; 26 conserved motifs were found among these GmDIRs. The GmDIRs were grouped into four subfamilies, DIR-a, DIR-b, DIR-e and DIR-f, based on a phylogenetic analysis, and 24 duplicated gene pairs were identified. Differences in the cis-acting elements in the GmDIR promoter regions might result in distinct expression patterns of GmDIRs in different tissues. In addition, GmDIR27 had a close relationship with the pod dehiscence gene GmPdh1, and overexpression of GmDIR27 increased pod dehiscence by affecting several pod dehiscence-related gene expressions. Generally, our results provide essential information that aids future efforts to functionally characterize soybean GmDIR genes.

5.
Genes (Basel) ; 11(11)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114541

RESUMO

In fish, sperm motility activation is one of the most essential procedures for fertilization. Previous studies have mainly focused on the external environmental effects and intracellular signals in sperm activation; however, little is known about the metabolic process of sperm motility activation in fish. In the present study, using ricefield eel (Monopterus albus) sperm as a model, metabonomics was used to analyze the metabolic mechanism of the sperm motility activation in fish. Firstly, 529 metabolites were identified in the sperm of ricefield eel, which were clustered into the organic acids, amino acids, nucleotides, benzene, and carbohydrates, respectively. Among them, the most abundant metabolites in sperm were L-phenylalanine, DL-leucine, L-leucine, lysolecithin choline 18:0, L-tryptophan, adenine, hypoxanthine, 7-Methylguanine, shikimic acid, and L-tyrosine. Secondly, compared to pre-activated sperm, the level of S-sulfo-L-cysteine and L-asparagine were both increased in the post-activated sperm. Ninety-two metabolites were decreased in the post-activated sperm, including quinic acid, acetylsalicylic acid, 7,8-dihydro L-biopterin, citric acid, glycylphenylalanine, and dihydrotachysterol (DHT). Finally, basing on the pathway analysis, we found that the changed metabolites in sperm motility activation were mainly clustered into energy metabolism and anti-oxidative stress. Fish sperm motility activation would be accompanied by the release of a large amount of energy, which might damage the genetic material of sperm. Thus, the anti-oxidative stress function is a critical process to maintain the normal physiological function of sperm.

6.
J Environ Qual ; 49(2): 335-345, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016435

RESUMO

Biochar is composed of carbonaceous and inorganic (ash) fractions. The structural properties of carbonaceous fractions and the composition of ash in biochar are both variable with pyrolysis temperature. However, it is unknown whether ash may play different roles in sorption of organic compounds to the carbonaceous fraction of biochars produced at different temperatures. Hence, in this study, the pristine biochars produced at 300-900°C and their corresponding deashed biochars were investigated, and the combined roles of carbonaceous fraction and ash in sorption of triclosan were compared. The results showed that the biochars produced at 300-400°C had high content of uncarbonized organic structure with dominating partition effect. The combination of uncarbonized organic structure and ash had comparable or even higher sorption coefficient (KD ) for triclosan at low concentration compared with a single uncarbonized organic structure. However, for the biochars produced at 600-900°C, which were mainly composed of carbonized or graphitized carbon structure, ash had significant effect on triclosan sorption by reducing surface adsorption and pore filling effect. The combination of carbonaceous fraction and ash decreased KD values for triclosan at any tested concentrations. In addition, the results of pH effect on sorption indicated that ash possibly decreased the electrostatic repulsion of deprotonated phenolic hydroxyl between biochars and triclosan. Accordingly, it will be more valuable to design biochars for pollutant sorption from the perspective of combined role of carbonaceous fraction and ash rather than a single role of carbonaceous fraction.


Assuntos
Triclosan , Madeira , Carvão Vegetal , Temperatura
7.
J Environ Qual ; 49(5): 1396-1407, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016453

RESUMO

The different effects of nitrogen-flow (NF) and air-limitation (AL) pyrolysis on the characteristics and nutrient retention of biochars (BCs) are unclear. Hence, in this study, BCs derived from bamboo, corn straw, and wheat straw were produced in AL and NF atmospheres at various temperatures (300-750 °C), and their different characteristics and nutrient retention rates were compared systematically. Nitrogen-flow pyrolysis facilitates C retention and graphitic C formation, and AL pyrolysis improves the polarity and supports the formation of oxygen-containing groups. With increasing pyrolysis temperature, C retention and graphitic C formation in BCs derived from AL pyrolysis decreases more significantly compared with BCs from NF pyrolysis. At 750 °C, the polarity and oxygen-containing groups of BCs derived from AL pyrolysis increase, whereas those from BCs derived from NF pyrolysis decrease. The observations are attributable to the AL and high-temperature-enhanced oxidization and gasification of C. An AL atmosphere with a higher pyrolysis temperature supports porosity and results in a larger specific surface area. Although pyrolysis temperature and atmosphere have negligible effects on nutrient retention, a low pyrolysis temperature facilitates the formation of water-soluble Ca, Mg, and P, and AL pyrolysis facilitates the formation of water-soluble P because the high pyrolysis temperature improves the pH and mineral stability of BCs, and air limitation facilitates the oxidation of organic P into PO4 3- . This study provides a reference for selecting AL or NF pyrolysis based on various pyrolysis temperatures to produce BCs and applying these in C sequestration, contaminant sorption, and soil quantity improvement.


Assuntos
Carvão Vegetal , Nitrogênio , Nutrientes , Temperatura
8.
Biology (Basel) ; 9(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911654

RESUMO

In mammals, epidermal growth factor (EGF) plays a vital role in both pituitary physiology and pathology. However, the functional role of EGF in the regulation of pituitary hormones has rarely reported in teleost. In our study, using primary cultured grass carp pituitary cells as an in vitro model, we examined the effects of EGF on pituitary hormone secretion and gene expression as well as the post-receptor signaling mechanisms involved. Firstly, we found that EGF significantly reduced luteinizing hormone (LHß) mRNA expression via ErbB1 coupled to ERK1/2 pathway, but had no effect on LH release in grass carp pituitary cells. Secondly, the results showed that EGF was effective in up-regulating mRNA expression of growth hormone (GH), somatolactin α (SLα) and somatolactin ß (SLß) via ErbB1 and ErbB2 and subsequently coupled to MEK1/2/ERK1/2 and PI3K/Akt/mTOR pathways, respectively. However, EGF was not effective in GH release in pituitary cells. Thirdly, we found that EGF strongly induced pituitary prolactin (PRL) release and mRNA expression, which was mediated by ErbB1 and subsequent stimulation of MEK1/2/ERK1/2 and PI3K/Akt/mTOR pathways. Interestingly, subsequent study further found that neurokinin B (NKB) significantly suppressed EGF-induced PRL mRNA expression, which was mediated by neurokinin receptor (NK2R) and coupled to AC/cAMP/PKA signal pathway. These results suggested that EGF could differently regulate the pituitary hormones expression in grass carp pituitary cells.

9.
Int J Genomics ; 2020: 2568640, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908854

RESUMO

RWP-RK proteins are important factors involved in nitrate response and gametophyte development in plants, and the functions of RWP-RK proteins have been analyzed in many species. However, the characterization of peanut RWP-RK proteins is limited. In this study, we identified 16, 19, and 32 RWP-RK members from Arachis duranensis, Arachis ipaensis, and Arachis hypogaea, respectively, and investigated their evolution relationships. The RWP-RK proteins were classified into two groups, RWP-RK domain proteins and NODULE-INCEPTION-like proteins. Chromosomal distributions, gene structures, and conserved motifs of RWP-RK genes were compared among wild and cultivated peanuts. In addition, we identified 12 orthologous gene pairs from the two wild peanut species, 13 from A. duranensis and A. hypogaea, and 13 from A. ipaensis and A. hypogaea. One, one, and seventeen duplicated gene pairs were identified within the A. duranensis, A. ipaensis, and A. hypogaea genomes, respectively. Moreover, different numbers of cis-acting elements in the RWP-RK promoters were found in wild and cultivated species (87 in A. duranensis, 89 in A. ipaensis, and 92 in A. hypogaea), and as a result, many RWP-RK genes showed distinct expression patterns in different tissues. Our study will provide useful information for further functional and evolutionary analysis of the RWP-RK genes.

10.
Mol Ther ; 28(10): 2191-2202, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32755566

RESUMO

Epigenetic alterations occur in many physiological and pathological processes. N6-methyladenosine (m6A) modification is the most prevalent modification in eukaryotic mRNAs. However, the role of m6A modification in pathological angiogenesis remains elusive. In this study, we showed that the level of m6A modification was significantly upregulated in endothelial cells and mouse retinas following hypoxic stress, which was caused by increased METTL3 levels. METTL3 silencing or METTL3 overexpression altered endothelial cell viability, proliferation, migration, and tube formation in vitro. METTL3 knockout in vivo decreased avascular area and pathological neovascular tufts in an oxygen-induced retinopathy model and inhibited alkali burn-induced corneal neovascularization. Mechanistically, METTL3 exerted its angiogenic role by regulating Wnt signaling through the m6A modification of target genes (e.g., LRP6 and dishevelled 1 [DVL1]). METTL3 enhanced the translation of LRP6 and DVL1 in an YTH m6A RNA-binding protein 1 (YTHDF1)-dependent manner. Collectively, this study suggests that METTL3-mediated m6A modification is an important hypoxic stress-response mechanism. The targeting of m6A through its writer enzyme METTL3 is a promising strategy for the treatment of angiogenic diseases.

11.
Inj Prev ; 26(6): 555-561, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32788224

RESUMO

OBJECTIVES: To assess the current status of injury prevention (IP) core competency among medical students majoring in public health in China and to advocate for incorporating IP in the medical curriculum. METHODS: The study used purposive sampling in eight medical universities in China in 2017, including 420 undergraduates and 763 graduates, using self-administered questionnaires based on the core competency instrument for IP with five domains (31 items): A) injury analysis and assessment (8 items), B) IP project planning and implementation (7 items), C) communication (6 items), D) community practice (5 items), and E) leadership and systematic thinking (5 items). The higher score indicated the higher level of proficiency of the ability (scores ranged from 1 to 5). We used linear regression model to test the effect of IP course experience on the core competency mean score after adjusting for potential confounders. RESULTS: The total mean score was 2.78 (SD=0.76, median=2.9, range=1-4.55) and 2.68 (SD=0.75, median=2.81, range=1-4.45) for undergraduates and graduates, respectively. There were 60% and 36% of undergraduates and graduates who have ever taken IP course, respectively. IP course class hours were positively associated with core competency level (P<0.05) across five domains (except for domain D) and the total. CONCLUSION: The core competency level is relatively low among public health students in China. Setting IP courses should be considered as an effective way to improve students' core competency. It is a step moving towards the IP education promotion, and further boosting the field of public health.

12.
Brain Behav ; 10(10): e01796, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32815287

RESUMO

INTRODUCTION: Autism spectrum disorder (ASD) is a complex and prevalent neurodevelopmental disorder characterized by deficits in social communication and social interaction as well as repetitive behaviors. Alterations in function connectivity are widely recognized in recent electroencephalogram (EEG) studies. However, most studies have not reached consistent conclusions, which could be due to the developmental nature and the heterogeneity of ASD. METHODS: Here, EEG coherence analysis was used in a cohort of children with ASD (n = 13) and matched typically developing controls (TD, n = 15) to examine the functional connectivity characteristics in long-distance and short-distance electrode pairs. Subsequently, we explore the association between the connectivity strength of coherence and symptom severity in children with ASD. RESULTS: Compared with TD group, individuals with ASD showed increased coherence in short-distance electrode pairs in the right temporal-parietal region (delta, alpha, beta bands), left temporal-parietal region (all frequency bands), occipital region (theta, alpha, beta bands), right central-parietal region (delta, alpha, beta bands), and the prefrontal region (only beta band). In the long-distance coherence analysis, the ASD group showed increased coherence in bilateral frontal region, temporal region, parietal region, and frontal-occipital region in alpha and beta bands. The strength of such connections was associated with symptom severity. DISCUSSION: Our study indicates that abnormal connectivity patterns in neuroelectrophysiology may be of critical importance to acknowledge the underlying brain mechanism.

13.
Sci Total Environ ; 742: 140416, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721714

RESUMO

A crucial mechanism for the application of biochar in soil improvement is the direct release of nutrients from biochar. Low molecular weight organic acids (LMWOAs) ubiquitously exist in soil. However, the mechanism of LMWOAs-mediated release of nutrients from biochars remains little known. Ten biochars with different mineral element stoichiometric ratio were produced, and four LMWOAs [acetic (HAc), glycolic (GA), tartaric (TA), and citric acids (CA)] were employed, to enunciate the influence mechanism of LMWOAs on the release of phosphorus and potassium from biochar. The results showed that HAc suppressed the release of P from biochars, while TA and CA facilitated the release of P from biochars with high ratios of polyvalent metals to P. A new mechanism was proposed that the deprotonated HAc combined with the dissolved HPO42- or H2PO4- to form a complex through hydrogen bond and cation bridging. The hydrophobic methyl group of HAc was exposed outside of the complex, which decreased the water-solubility of phosphate. Meanwhile, a high ratio of polyvalent metals to P benefited more P to combine with polyvalent metals, which decreased the water-solubility of P, but the deprotonated TA and CA are polyvalent anions that could substitute this part of P by anion exchange. Also, LMWOAs promoted the release of K from biochars with low K/(P + S) ratios, possibly due to unionized carboxyl of LMWOAs served as a hydrogen bond donor to displace K out of biochars. This study gives a deep understanding of the fate of biochar originated nutrients response to LMWOAs.


Assuntos
Fósforo , Poluentes do Solo/análise , Carvão Vegetal , Minerais , Peso Molecular , Potássio , Solo
14.
Antioxidants (Basel) ; 9(8)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707948

RESUMO

A casein phosphopeptide (CPP) fraction derived from tryptic hydrolysis of bovine casein was evaluated for antioxidant activity. Conjugations or mixtures of CPP with polysaccharide, galactomannan (Gal), or xyloglucan (Xyl) were prepared to evaluate potential enhancement of CPP antioxidant activity. The effect of calcium was also investigated. The CPP preparation alone was effective at scavenging hydroxyl radicals and sequestering Fe2+ to protect against Fenton reaction-induced deoxyribose oxidation in non-site-specific (up 63.3% inhibition) and site-specific (up 32.1% inhibition) binding assays, respectively. CPP also effectively quenched 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radicals (ABTS•+) to an extent of 67.6% scavenging in an aqueous system. In a soybean lecithin liposome system, CPP exhibited effective protection against peroxyl radical-induced liposomal peroxidation (38.3% of control in terms of rate of propagation). Conjugating CPP with Gal or Xyl polysaccharides using Maillard reaction conditions significantly reduced activity in the Fenton reaction-deoxyribose assays, while exhibiting no effect on the antioxidant activity of native CPP in both the ABTS and liposome assays, respectively. These results represent comparative antioxidant capacity of the native CPP and associated conjugates in phases that varied in relative hydrophilic and hydrophobic character. We conclude that CPP has the potential to act as both a primary and secondary antioxidant by displaying transition metal ion sequestering activity and free radical quenching activity. Improvements in antioxidant activity of CPP by Maillard-type conjugation with Xyl or Gal were relatively small and model-specific.

15.
J Gynecol Obstet Hum Reprod ; 49(9): 101780, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32360632

RESUMO

OBJECTIVE: To describe the frequency and risk factors of endometrial hyperplasia (EH) in infertile women undergoing their first IVF/ICSI treatment. METHODS: A total of 3198 infertile women undergoing their first IVF/ICSI cycle were recruited retrospectively from a fertility treatment center. Endometrial scratching and biopsy were conducted before IVF/ICSI treatment. The relationship between EH and clinical characteristics were analyzed. RESULTS: EH without atypia, atypical hyperplasia, and endometrial cancer (EC) were diagnosed in 94 (2.94%), three (0.093%), and two (0.063%) women, respectively. The frequencies of EH were higher in patients with abnormal uterine bleeding (i.e. menstrual cycle irregularity in terms of frequency, volume, or length; 6.8% vs. 1.6%, P < 0.001, OR = 4.42), obesity (4.1% vs. 2.7%, P = 0.044, OR = 1.55), and elevated fasting glucose (4.6% vs. 2.5%, P = 0.017, OR = 1.85). In the multivariate analyses, all the three factors (abnormal uterine bleeding, obesity, elevated fasting glucose) were independently associated with risk of EH. In the subgroup analysis, among women with abnormal uterine bleeding, the frequency of EH in the elevated fasting glucose group was 10.7%, which was higher than that of the normal fasting glucose group (5.6%), even after adjustment for BMI (P = 0.014, OR = 1.53). CONCLUSION: The frequency of EH in infertile women undergoing their first IVF/ICSI treatment was approximately 3%. Elevated fasting glucose was an independent risk factor for EH in infertile women undergoing IVF/ICSI.

16.
Food Res Int ; 133: 109112, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32466923

RESUMO

The present research investigated the relationships among sensory attributes and volatile components in dry porcini mushrooms by multivariate statistical analyses. The sensory characteristics were based on quantitative descriptive analysis and consumer hedonic assessment. The volatile compounds were extracted by solid-phase microextraction, then were identified using gas chromatography-mass spectrometry and gas chromatography-olfactometry. The results showed that the high hedonic rating of porcini mushrooms was due in part to its aroma notes such as seasoning-like, roasted, cacao-like and smoky. High hedonic liking and positive aromas of porcini mushrooms could be responsible for the volatiles including 3-(methylthio)propanal, 3-(methylthio)propanol, pyrazines, phenolic and furanone components. On the other hand, raw mushroom-like, cardboard-like, as well as sweaty attributes were attributed to the relatively low hedonic liking of porcini mushrooms, which correlated with high contents of 1-octen-3-ol, octanal, 2-pentylfuran and 3-methylbutanoic acid. The information reported here could be important for the quality control of commercial porcini mushrooms by providing an approach to strengthen the interpretation of sensory data by showing how they were affected by the chemical properties.

17.
Foods ; 9(4)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252248

RESUMO

The key aroma compounds in smoke-cured pork leg were characterized by gas chromatography-olfactometry coupled with aroma extract dilution analysis (GC-O/AEDA), odor activity value (OAV), recombination modeling, and omission tests. Ranking analysis showed that pork leg smoke-cured for 18 days had the best sensory qualities, with strong meaty, smoky, roasty, woody, and greasy attributes. Thirty-nine aroma-active regions with flavor dilution (FD) factors ranging from 9 to 6561 were detected. Overall, 3-ethylphenol had the highest FD factor of 6561, followed by 2,6-dimethoxyphenol, 3,4-dimethylphenol, 4-ethylguaiacol, 4-methylguaiacol, 3-methylphenol, and 2-acetyl-1-pyrroline, with FD ≥243. Among 39 aroma compounds, 27 compounds with OAVs ≥1 and were potent odorants. A similarity of 90.73% between the recombination model and traditional Hunan Smoke-cured Pork Leg (THSL) sample was obtained. Omission tests further confirmed that (E)-2-nonenal, 2-methoxy-4-vinylphenol, guaiacol, 3-ethylphenol, 2,6-dimethylphenol, 2-acetyl-1-pyrroline, and methional were key odorants in smoke-cured pork leg. Additionally, 2-acetyl-1-pyrroline (38.88 µg/kg), which contributes to a roasty aroma, was characterized here as a key odorant of smoke-cured pork leg for the first time.

18.
Food Chem ; 318: 126520, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32155563

RESUMO

Gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic quantitative descriptive analysis (D-QDA) were combined to explore the aroma release and perception from the retronasal cavity during bread consumption. D-QDA results elucidated that the sweet, creamy, and roasty notes were the most active attributes during oral processing. The final stage of oral processing had the most complicated changing pattern, followed by the intermediate and initial stages. Thirteen aroma compounds were detected in the retronasal cavity, of which eight had odor activity values (OAVs) greater than 1. The total OAV changing pattern was consistent with the D-QDA results. Addition experiments further confirmed that acetoin, 2,3-butanedione, and 3-(methylthio)propanal were key aroma compounds contributing to retronasal olfaction. 2,3-Butanedione and 3-(methylthio)propanal were both identified as key odorants in the mouth cavity and retronasal cavity during oral processing, but they had 30% loss during the breath delivery from the mouth cavity to the retronasal cavity.


Assuntos
Pão/análise , Odorantes/análise , Acetoína/análise , Adulto , Diacetil/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Cavidade Nasal , Reprodutibilidade dos Testes , Olfato , Paladar , Triticum , Compostos Orgânicos Voláteis/análise
19.
J Med Virol ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129506

RESUMO

The presence of a quasispecies in hepatitis E virus (HEV) infection has been documented, however, the implications of a quasispecies in HEV-host interaction are poorly understood. Here, we analyzed the whole genome sequences of a HEV 4d from the feces and liver biopsy of a patient during the icteric and convalescent phases in an acute hepatitis E infection. Viral RNAs were extracted, reversely transcribed and seven fragments encompassing the entire viral genome were amplified and cloned. By sequencing multiple colonies of each cloned viral genome amplicon with Sanger sequencing, we verified the existence of the HEV quasispecies or intra-host genetic variations within the fecal and liver biopsy samples. There were broader genetic variations in the HEV ORF1 region including the PCP, HPX, and RdRp regions during the convalescent phase whereas more genetic variations in the ORF2 P domain during the icteric phase. The quasispecies dynamics might reflect host immune pressure during viral clearance.

20.
Subst Use Misuse ; 55(6): 954-963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32009488

RESUMO

Background: Consumption of alcohol among adults in Inner Mongolia is high even among health professionals. Little is known of the alcohol consumption patterns of health-profession students. Objectives: To assess the association of knowledge of alcohol-related harm (KAH), and exposure to media-based promotional alcohol sales advertisements (PASA) and alcohol hazard warnings (AHW) with drinking frequency of health-profession university students. Methods: Health-profession students (N = 1277) in the Medical University of Inner Mongolia were interviewed in 2017 regarding their alcohol drinking frequency, KAH, and exposure to PASA and AHW. Multinomial logistic regression was used to evaluate associations between exposure and drinking frequency. Results: Overall, 9% were nondrinkers, 35% occasional drinkers, and 56% frequent drinkers. Females were slightly less commonly drinkers but more commonly frequent drinkers. The prevalence of drinking decreased with age. Mongolians were more commonly frequent drinkers than Han. A majority of students had low KAH. Exposure to PASA was more common among drinkers, and exposure to AHW more common among nondrinkers. The main reason for drinking was social gathering. The relative probability of being an occasional or frequent drinker was lower among older students, those with higher KAH, and those exposed to AHW on television and internet but higher among those exposed to PASA in mini-supermarkets on campus. Conclusions: Students' drinking behavior was associated with low KAH and exposure to alcohol advertisements and warning media messages. Prevalence of frequent drinking might be reduced by wider use of AHW on internet and television and improving the level of knowledge of alcohol-related harm.

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