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1.
Behav Brain Res ; : 112319, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31669346

RESUMO

Chronic cerebral hypoperfusion is an important risk factor for vascular dementia (VaD) and other brain dysfunctions, for which there are currently no effective medications available. In the present study, we investigated the potential therapeutic effects of cornel iridoid glycoside (CIG) on VaD in rats modeled by permanent bilateral common carotid artery ligation (2-vessel occlusion, 2VO). The object recognition test (ORT) and Morris water maze (MWM) test were conducted to evaluate the learning and memory function. Western blot analysis and immunohistochemical staining were used to detect the expression of related proteins. Results showed that intragastric administration of CIG (30, 60, and 120 mg/kg) for 3 months significantly increased the discrimination index in ORT and decreased the escape latency in MWM test, ameliorating the learning and memory deficit in 2VO rats. Further data indicated that CIG increased the expression of neurotrophic factors (NGF and BDNF) and their receptors (TrkA and TrkB), glutamate receptor subunits (NMDAR1 and GluR2) in the cerebral cortex and hippocampus of 2VO rats. In addition, CIG elevated the expression of PI3K subunits p110α and p85, further upregulated the phosphorylation of Akt, GSK3ß-ser9 and CREB in the cerebral cortex and hippocampus at 3 months after 2VO surgery. Collectively, CIG treatment improved learning and memory deficit induced by chronic cerebral hypoperfusion via increasing neurotrophic factors thus protecting glutamate receptors and activating PI3K/Akt/GSK3ß/CREB signaling pathway in rats. These results suggest that CIG may be beneficial to VaD therapy.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31670894

RESUMO

Sulfone motifs have attracted considerable interest due to their extensive applications in pharmaceuticals and organic photoconducting materials. Conventionally, sulfones are prepared via the oxidation of sulfides with strong oxidants, which has low functional group compatibility. Herein, a multicomponent reductive cross-coupling involving an inorganic salt ( sodium metabisulfite) for the straightforward construction of sulfones is disclosed. Both intramolecular and intermolecular reductive cross-couplings were comprehensively explored, and diverse sulfones were accessible from the corresponding alkyl and aryl halide s. Intramolecular cyclic sulfones were systematically obtained from five- to twelve-membered rings . Naturally occurring aliphatic systems , such as steroids, saccharides and amino acids, were highly compatible with the SO 2 -insertion reductive cross-coupling . Four clinically applied drug molecules, which include multiple heteroatoms and functional groups with active hydrogens, were successfully prepared via a late-stage SO 2 insertion. Mechanistic studies demonstrated that alkyl radicals and sulfonyl radicals were both involved as intermediates in this transformation.

3.
NPJ Syst Biol Appl ; 5: 38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632690

RESUMO

Gene regulatory networks (GRNs) have been widely used as a fundamental tool to reveal the genomic mechanisms that underlie the individual's response to environmental and developmental cues. Standard approaches infer GRNs as holistic graphs of gene co-expression, but such graphs cannot quantify how gene-gene interactions vary among individuals and how they alter structurally across spatiotemporal gradients. Here, we develop a general framework for inferring informative, dynamic, omnidirectional, and personalized networks (idopNetworks) from routine transcriptional experiments. This framework is constructed by a system of quasi-dynamic ordinary differential equations (qdODEs) derived from the combination of ecological and evolutionary theories. We reconstruct idopNetworks using genomic data from a surgical experiment and illustrate how network structure is associated with surgical response to infrainguinal vein bypass grafting and the outcome of grafting. idopNetworks may shed light on genotype-phenotype relationships and provide valuable information for personalized medicine.

4.
Nucleic Acids Res ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31647098

RESUMO

Alternative splicing is emerging as an oncogenic mechanism. In prostate cancer, generation of constitutively active forms of androgen receptor (AR) variants including AR-V7 plays an important role in progression of castration-resistant prostate cancer (CRPC). AR-V7 is generated by alternative splicing that results in inclusion of cryptic exon CE3 and translation of truncated AR protein that lacks the ligand binding domain. Whether AR-V7 can be a driver for CRPC remains controversial as the oncogenic mechanism of AR-V7 activation remains elusive. Here, we found that KDM4B promotes AR-V7 and identified a novel regulatory mechanism. KDM4B is phosphorylated by protein kinase A under conditions that promote castration-resistance, eliciting its binding to the splicing factor SF3B3. KDM4B binds RNA specifically near the 5'-CE3, upregulates the chromatin accessibility, and couples the spliceosome to the chromatin. Our data suggest that KDM4B can function as a signal responsive trans-acting splicing factor and scaffold that recruits and stabilizes the spliceosome near the alternative exon, thus promoting its inclusion. Genome-wide profiling of KDM4B-regulated genes also identified additional alternative splicing events implicated in tumorigenesis. Our study defines KDM4B-regulated alternative splicing as a pivotal mechanism for generating AR-V7 and a contributing factor for CRPC, providing insight for mechanistic targeting of CRPC.

5.
Bioorg Med Chem ; : 115153, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648877

RESUMO

In this study, a series of shikonin derivatives combined with benzoylacrylic had been designed and synthesized, which showed an inhibitory effect on both tubulin and the epidermal growth factor receptor (EGFR). In vitro EGFR and cell growth inhibition assay demonstrated that compound PMMB-317 exhibited the most potent anti-EGFR (IC50 = 22.7 nM) and anti-proliferation activity (IC50 = 4.37 µM) against A549 cell line, which was comparable to that of Afatinib (EGFR, IC50 = 15.4 nM; A549, IC50 = 6.32 µM). Our results on mechanism research suggested that, PMMB-317 could induce the apoptosis of A549 cells in a dose- and time-dependent manner, along with decrease in mitochondrial membrane potential (MMP), production of ROS and alterations in apoptosis-related protein levels. Also, PMMB-317 could arrest cell cycle at G2/M phase to induce cell apoptosis, and inhibit the EGFR activity through blocking the signal transduction downstream of the mitogen-activated protein MAPK pathway and the anti-apoptotic kinase AKT pathway; typically, such results were comparable to those of afatinib. In addition, PMMB-317 could suppress A549 cell migration through the Wnt/ß-catenin signaling pathway in a dose-dependent manner. Additionally, molecular docking simulation revealed that, PMMB-317 could simultaneously combine with EGFR protein (5HG8) and tubulin (1SA0) through various forces. Moreover, 3D-QSAR study was also carried out, which could optimize our compound through the structure-activity relationship analysis. Furthermore, the in vitro and in vivo results had collectively confirmed that PMMB-317 might serve as a promising lead compound to further develop the potential therapeutic anticancer agents.

6.
Work ; 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31658093

RESUMO

BACKGROUND: Cleaning workers experience severe musculoskeletal symptoms. OBJECTIVE: The objective of this paper was to examine musculoskeletal symptoms in cleaners of different heights to evaluate the effects of height on working postures in the work environment (schools). METHODS: We used a three-stage method including using the Nordic Musculoskeletal Questionnaire (NMQ) to evaluate musculoskeletal symptoms, a task analysis to confirm typical cleaning tasks, and the OVAKO Working Posture Assessment System (OWAS) for posture analysis. Multinomial logistic regression was performed to evaluate the adjusted effects of individual characteristics on painful body regions, using individuals without any pain as the reference category. RESULTS: This study found that the prevalence of musculoskeletal symptoms is very high for cleaners, especially in the shoulders, elbows, and lower back. Odds ratios for the accumulation of two or more risk factors were higher among men and were inversely associated with national economic indicators. The relatively high prevalence of musculoskeletal symptoms may stem from the multiple operations involved in cleaning tasks, such as trash collecting, floor mopping, toilet cleaning, and mirror polishing. Workers of different heights had differential work loadings for different tasks. CONCLUSIONS: This paper proposes recommendations for job adaptations and occupational safety training. Cleaners of different heights execute the typical tasks via different postures, and awkward postures often result in musculoskeletal symptoms. Cleaners should be provided with specific tools and training regarding working postures on the basis of height. These findings can be used as a reference for related operation designs and task improvements to ensure correct tool usage and safer working postures during cleaning.

7.
HPB (Oxford) ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31607637

RESUMO

BACKGROUND: A clear definition of "early recurrence" after hepatocellular carcinoma (HCC) resection is still lacking. This study aimed to determine the optimal cutoff between early and late HCC recurrence, and develop nomograms for pre- and postoperative prediction of early recurrence. METHODS: Patients undergoing HCC resection were identified from a multi-institutional Chinese database. Minimum P-value approach was adopted to calculate optimal cut-off to define early recurrence. Pre- and postoperative risk factors for early recurrence were identified and further used for nomogram construction. The results were externally validated by a Western cohort. RESULTS: Among 1501 patients identified, 539 (35.9%) were recurrence-free. The optimal length to distinguish between early (n = 340, 35.3%) and late recurrence (n = 622, 64.7%) was 8 months. Multivariable logistic regression analyses identified 5 preoperative and 8 postoperative factors for early recurrence, which were further incorporated into preoperative and postoperative nomograms (C-index: 0.785 and 0.834). The calibration plots for the probability of early recurrence fitted well. The nomogram performance was maintained using the validation dataset (C-index: 0.777 for preoperative prediction and 0.842 for postoperative prediction). CONCLUSIONS: An interval of 8 months was the optimal threshold for defining early HCC recurrence. The two web-based nomograms have been published to allow accurate pre- and postoperative prediction of early recurrence. These may offer useful guidance for individual treatment or follow up for patients with resectable HCC.

8.
J Neural Eng ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31585451

RESUMO

OBJECTIVE: State-of-the-art invasive brain-machine interfaces (BMIs) have shown significant promise, but rely on external electronics and wired connections between the brain and these external components. This configuration presents health risks and limits practical use. These limitations can be addressed by designing a fully implantable BMI similar to existing FDA-approved implantable devices. Here, a prototype BMI system whose size and power consumption are comparable to those of fully implantable medical devices was designed and implemented, and its performance was tested at the benchtop and bedside. APPROACH: A prototype of a fully implantable BMI system was designed and implemented as a miniaturized embedded system. This benchtop analogue was tested in its ability to acquire signals, train a decoder, perform online decoding, wirelessly control external devices, and operate independently on battery. Furthermore, performance metrics such as power consumption were benchmarked. MAIN RESULTS: An analogue of a fully implantable BMI was fabricated with a miniaturized form factor. A patient undergoing epilepsy surgery evaluation with an electrocorticogram (ECoG) grid implanted over the primary motor cortex was recruited to operate the system. Seven online runs were performed with an average binary state decoding accuracy of 87.0% (lag optimized, or 85.0% at fixed latency). The system was powered by a wirelessly rechargeable battery, consumed ∼150 mW, and operated for >60 hours on a single battery cycle. SIGNIFICANCE: The BMI analogue achieved immediate and accurate decoding of ECoG signals underlying hand movements. A wirelessly rechargeable battery and other supporting functions allowed the system to function independently. In addition to the small footprint and acceptable power and heat dissipation, these results suggest that fully implantable BMI systems are feasible.

9.
Nat Cell Biol ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570835

RESUMO

The repression of transposons by the Piwi-interacting RNA (piRNA) pathway is essential to protect animal germ cells. In Drosophila, Panoramix enforces transcriptional silencing by binding to the target-engaged Piwi-piRNA complex, although the precise mechanisms by which this occurs remain elusive. Here, we show that Panoramix functions together with a germline-specific paralogue of a nuclear export factor, dNxf2, and its cofactor dNxt1 (p15), to suppress transposon expression. The transposon RNA-binding protein dNxf2 is required for animal fertility and Panoramix-mediated silencing. Transient tethering of dNxf2 to nascent transcripts leads to their nuclear retention. The NTF2 domain of dNxf2 competes dNxf1 (TAP) off nucleoporins, a process required for proper RNA export. Thus, dNxf2 functions in a Panoramix-dNxf2-dependent TAP/p15 silencing (Pandas) complex that counteracts the canonical RNA exporting machinery and restricts transposons to the nuclear peripheries. Our findings may have broader implications for understanding how RNA metabolism modulates heterochromatin formation.

10.
Nat Genet ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570895

RESUMO

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a 'one-step operation'. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars 'Smooth Cayenne' and 'Queen' exhibited ancient and recent admixture, while 'Singapore Spanish' supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.

11.
Br J Educ Psychol ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573072

RESUMO

BACKGROUND: The dropout rate of Chinese elementary school students after 2007 rose again. Little research to date has identified individual differences in pathways of academic engagement to discern those at risk of disengagement and dropout from schools, as well as the longitudinal linkages between cognitive beliefs with academic engagement. AIMS: Examine the developmental trajectories of cognitive, emotional, and behavioural engagement, and assess relations between the implicit theory of intelligence and academic self-efficacy and the development of academic engagement. SAMPLE AND METHODS: We recruited 532, 450, and 415 elementary students to rate on self-report scales in April 2016 (T1), October 2016 (T2), and April 2017 (T3), respectively. Trajectories of academic engagement were analysed by using a multiple-process growth mixture model, and levels of entity theory of intelligence and academic self-efficacy between engagement groups were compared by using analysis of variance. RESULTS: We categorized the students into four groups: persistent (71.24%), climbing (6.01%), descending (16.54%), and struggling engagement (6.20%) groups. Within each group, the levels of academic self-efficacy from T1 to T3 demonstrated a consistent trend with the engagement trajectory; the levels of the implicit theory of intelligence over time showed the reverse trend. CONCLUSIONS: Attention should be given more on the students from the descending and struggling groups. The implicit theory of intelligence and academic self-efficacy showed different longitudinal associations with engagement trajectories.

12.
Br J Haematol ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573077

RESUMO

Decitabine is a DNA-hypomethylating agent that has been widely applied for the treatment of acute myeloid leukaemia (AML) patients who are elderly or unfit for intensive therapy. Although effective, the complete response rate to decitabine is only around 30% and the overall survival remains poor. Emerging data support that regulation of DNA methylation is critical to control immune cell development, differentiation and activation. We hypothesize that defining how decitabine influences the immune responses in AML will facilitate the development of novel immune-based leukaemia therapeutics. Here, we performed phenotypic and functional immune analysis on clinical samples from AML patients receiving decitabine treatment and demonstrated a significant impact of decitabine on the immune system. T-cell expression of inhibitory molecules was upregulated and the ability of CD8 T cells to produce cytokines was decreased upon decitabine treatment. Importantly, in an unbiased comprehensive analysis, we identified a unique immune signature containing a cluster of key immune markers that clearly separate patients who achieved complete remission after decitabine from those who failed to do so. Therefore, this immune signature has a strong predictive value for clinical response. Collectively, our study suggests that immune-based analyses may predict clinical response to decitabine and provide a therapeutic strategy to improve the treatment of AML.

13.
J Am Chem Soc ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31589435

RESUMO

The selective and temporal control of protein activity in living cells provides a powerful tool to manipulate cellular function and to develop pro-protein therapeutics (PPT) for targeted therapy. In this work, we reported a facile but general chemical approach to design PPT by modulating protein activity in response to endogenous enzyme of disease cells, and its potential for targeted cancer therapy. We demonstrated that the chemical modification of a protein with quinone propionic acid (QPN), a ligand that could be reduced by tumor-cell-specific NAD(P)H dehydrogenase [quinone] 1 (NQO1), was reversible in the presence of NQO1. Importantly, the QPN-modified cytochrome c (Cyt c-QPN) and ribonuclease A (RNase A-QPN) showed NQO1-regulated protein activity in a highly selective manner. Furthermore, the intracellular delivery of RNase A-QPN using a novel type of lipid-based nanoparticles, and subsequent protein activation by cellular NQO1, selectively inhibit cancer cell growth in vitro and effectively suppress tumor growth in vivo. We believe that our approach increases the number of potentially useful chemical tools for reversibly controlling the structure and function of protein using a disease-cell-specific enzyme, opening opportunities in the study of dynamic biological processes and developing precise protein therapeutics.

14.
Inflamm Bowel Dis ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31626701

RESUMO

INTRODUCTION: Ulcerative colitis (UC) associated with primary sclerosing cholangitis (PSC) is a rare phenotype. We aimed to assess patients with UC-PSC or UC alone and describe differences in clinical and phenotypic characteristics, antitumor necrosis factor (TNF) therapy, and long-term clinical outcomes. METHODS: This retrospective multicenter cohort study included patients who received a diagnosis of UC from 1962 through 2015. We evaluated clinical factors associated with UC-PSC vs UC alone and assessed associations by using multivariable logistic regression models. RESULTS: Among 522 patients with UC, 56 (10.7%) had PSC. Compared with UC alone, patients with UC-PSC were younger (younger than 20 years) at diagnosis (odds ratios [OR], 2.35; adjusted P = 0.02) and had milder UC severity (adjusted P = 0.05), despite having pancolonic involvement (OR, 7.01; adjusted P < 0.001). In the biologics era (calendar year 2005 to 2015), patients with UC-PSC less commonly received anti-TNF therapy compared with patients with UC (OR, 0.38; adjusted P = 0.009), but their response rates were similar. Fewer patients with UC-PSC received corticosteroids (OR, 0.24; adjusted P = 0.005) or rectal 5-aminosalicyte acid (OR, 0.26; adjusted P < 0.001). Other differences were identified that were not statistically significant in a multivariable model: patients with UC-PSC more commonly were male, had lower rates of smoking, and had higher rates of colorectal cancer and colectomy. DISCUSSION: This study identified a unique phenotype of UC with concurrent PSC, which had different clinical behavior compared with UC only. These phenotypic characteristics can help identify high-risk patients with UC before PSC is diagnosed and guide different management and monitoring strategies.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31614749

RESUMO

With the aging of the population and the upgrading of the consumption structure of national health demand in China, it has become a new trend for the public to actively seek health products and services on social networks. Based on the theory of reasoned behavior and the theory of expectancy confirmation, this study aims to analyze the cognitive factors and their effects on WeChat users' purchase intention in the process of health product consumption. Considering that safety is a key feature of health products that distinguishes them from other consumer products, the "satisfaction" concept in the expectancy confirmation model is replaced by "trust" in this study. Two hundred and two (202) valid samples were collected by a questionnaire survey to analyze their intentions to buy health products on WeChat. Theoretical models and corresponding research hypotheses were verified by structural equation modeling. The research results show that emotional price and emotional experience are positively correlated with trust and purchase intention. There is an obvious negative correlation between privacy invasion and trust. Expectation confirmation is positively associated with trust. Moreover, the intermediary test shows that trust has completely mediated between emotional price and purchase intention, and trust also has a full intermediary effect on expectation confirmation and purchase intention.

16.
Br J Haematol ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31610612

RESUMO

Significant phenotypic heterogeneity exists in patients with all subtypes of myeloproliferative neoplasms (MPN), including essential thrombocythaemia (ET). Single-cell RNA sequencing (scRNA-Seq) holds the promise of unravelling the biology of MPN at an unprecedented level of resolution. Herein we employed this approach to dissect the transcriptomes in the CD34+ cells from the peripheral blood of seven previously untreated ET patients and one healthy adult. The mutational profiles in these patients were as follows: JAK2 V617F in two, CALR in three (one type I and two type II) and triple-negative (TN) in two. Our results reveal substantial heterogeneity within this enrolled cohort of patients. Activation of JAK/STAT signalling was recognized in discrepant progenitor lineages among different samples. Significantly disparate molecular profiling was identified in the comparison between ET patients and the control, between patients with different driver mutations (JAK2 V617F and CALR exon 9 indel), and even between patients harbouring the same driver. Intra-individual clonal diversity was also found in the CD34+ progenitor population of a patient, possibly indicating the presence of multiple clones in this case. Estimation of subpopulation size based on cellular immunophenotyping suggested differentiation bias in all analysed samples. Furthermore, combining the transcriptomic information with data from targeted sequencing enabled us to unravel key somatic mutations that are molecularly relevant. To conclude, we demonstrated that scRNA-Seq extended our knowledge of clonal diversity and inter-individual heterogeneity in patients with ET. The obtained information could potentially leapfrog our efforts in the elucidation of the pathogenesis of the disease.

17.
J Agric Food Chem ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657554

RESUMO

In this study, a type of thiazolium-labeled 1,3,4-oxadiazole thioether bridged by diverse alkyl chain lengths was constructed. The antimicrobial activity of the fabricated thioether towards plant pathogenic bacteria and fungi was then screened. Antibacterial evaluation indicated that title compounds possess specific characteristics that enable it to severely attack three phytopathogens, namely, Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri with minimal EC50 of 0.10, 3.27, and 3.50 µg/mL, respectively. Three-dimensional quantitative structure-activity relationship models were established to direct the following excogitation for exploring higher active drugs. The in vivo study against plant bacterial diseases further identified the prospective application of title compounds as alternative antibacterial agents. The proteomic technique, scanning electron microscopy patterns, and fluorescence spectrometry were exploited to investigate the antibacterial mechanism. Additionally, some target compounds performed superior inhibitory actions against three tested fungal strains. In view of their simple molecular architecture and highly efficient bioactivity, these substrates could be further explored as promising surrogates for fighting against plant microbial infections.

18.
Int J Hematol ; 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655984

RESUMO

Inotuzumab ozogamicin (InO) is a targeted treatment for adults with relapsed or refractory B-cell acute lymphoblastic leukemia (ALL). InO was previously studied in INO-VATE, an international, open-label, randomized phase 3 trial comparing InO against standard of care (SoC). In the present subgroup analysis, we evaluated outcomes in the 55 Asian patients who were randomized in INO-VATE (31 InO and 24 SoC). Complete remission (CR) or CR with incomplete hematologic recovery (CRi) was achieved in 22/31 patients treated with InO versus 5/24 treated with SoC. In the InO arm, more of the patients achieving CR/CRi were minimal residual disease (MRD)-negative (17/22 versus 1/5), and more patients proceeded directly to hematopoietic stem cell transplantation (15/31 versus 3/24). Median overall survival for the respective arms was 5.8 versus 3.9 months (hazard ratio 0.67; 97.5% CI 0.28, 1.62). In the safety analysis (n = 51), the most common adverse events were hematologic. Sinusoidal obstruction syndrome was reported in five InO patients and one SoC patient. In conclusion, Asian patients with relapsed or refractory B-cell ALL experienced improved efficacy with InO versus SoC, with an efficacy and safety profile consistent with results of the overall INO-VATE population.Clinical trial registration: ClinicalTrials.gov identifier: NCT01564784.

19.
J Food Sci ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31602667

RESUMO

This research aimed to compare the effects of monosodium glutamate (MSG) and its alternatives on sensory characteristics of chicken soup. High-performance liquid chromatography analysis was carried out to quantify umami substances in potential MSG alternatives. Two mushroom extracts (CE and MC), one tomato extract (TC), and one yeast extract (YE) powders were selected due to their high equivalent umami concentration (EUC). These extracts together with MSG were then applied individually at four different levels (CE, MC, TC, MSG: 0.05%, 0.1%, 0.2%, 0.4%; YE: 0.0125%, 0.025%, 0.05%, 0.1%) in chicken soup in order to compare their impact on major sensory attributes using the degree of difference from control (DODC) test. Our results showed that all four extracts at all the usage levels exhibited an enhancement effect on the overall flavor, meaty flavor, saltiness, and umami taste. The extent of enhancement depended on the type of the alternative and its usage level. Higher levels of MSG alternatives (except YE) suppressed the chicken flavor. YE had similar enhancement effects as MSG on umami and salty tastes already at lower usage levels. At the lowest concentration, TC showed a stronger enhancement effect than MSG, but its effect on most attributes decreased as the usage dose increased. Compared to CE, the other mushroom extract MC resembled MSG at most levels. Overall, the closest synergistic effect in chicken soup was noted with 0.1% MSG, 0.1% MC, and 0.025% YE. PRACTICAL APPLICATION: This study compared the enhancement effects of MSG and selected alternatives in chicken soup. Results will help food manufacturers who would like to replace MSG with natural umami substances in soup products to enhance flavor and reduce sodium chloride.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31661054

RESUMO

A Gram-stain-negative, rod-shaped bacterium, motile by means of a single polar flagellum, designated S-6-2T, was isolated from petroleum polluted river sediment in Huangdao, Shandong Province, PR China. The 16S rRNA gene sequence analysis revealed that S-6-2T represented a member of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas parafulva (97.5 %) and Pseudomonas fulva (97.5 %). Phylogenetic analysis based on 16S rRNA gene, concatenated 16S rRNA, gyrB, rpoB and rpoD genes and genome core-genes indicated that S-6-2T was affiliated with the members of the Pseudomonas pertucinogena group. The average nucleotide identity (ANI) and genome-to-genome distance between the whole genome sequences of S-6-2T and closely related species of the genus Pseudomonas within the P. pertucinogena group were less than 77.94 % and 20.5 %, respectively. Differences in phenotypic characteristics were also found between S-6-2T and the closely related species. The major cellular fatty acids (>10 %) were summed feature 8 (C18 : 1ω7c/ C18  : 1ω6c), C16 : 0, C17 : 0cyclo and C12 : 0. The predominant respiratory quinone was ubiquinone 9. The major polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), one unidentified lipid (L1), two unidentified phospholipids (PL1 and PL2) and an aminophospholipid (APL). The DNA G+C content of the genome of S-6-2T was 60.1 mol%. On the basis of the evidence from the polyphasic taxonomic study, strain S-6-2T can be classified as representative of a novel species of the genus Pseudomonas, for which the name Pseudomonas phragmitis sp. nov. is proposed. The type strain is S-6-2T (=CGMCC 1.15798T=KCTC 52539T).

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