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1.
Enzyme Microb Technol ; 134: 109487, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32044034

RESUMO

Haematococcus pluvialis could accumulate large amounts of triacylglycerol (TAG) and astaxanthin under various environmental stresses. To gain insights into the multiple defensive systems for carbon metabolism against nitrogen starvation, transcriptome analysis was performed. It was found that the genes related to carbon fixation, glycolysis, fatty acid and carotenoid biosynthesis pathways were up-regulated remarkably. Glyceraldehyde 3-phosphate (G3P) biosynthesis was accelerated with the enhanced C3 and C4 pathway. Meanwhile, the pyruvate kinase (PK) and pyruvate dehydrogenase E2 component (aceF) genes were significantly increased 12.9-fold and 13.9-fold, respectively, resulting more pyruvate and acetyl-CoA generation, which were beneficial to carotenoids and fatty acid biosynthesis. Methylerythritol 4-phosphate (MEP) pathway mediated carotenoid precursor isopentenyl diphosphate (IPP) synthesis, as the all eight related genes were up-regulated. The carbon flux toward astaxanthin biosynthesis with the increased astaxanthin pathway genes. The redistribution of carbon was also promoted for TAG accumulation. In addition, the up-regulation of diacylglycerol acyltransferase (DGAT) and phospholipid: diacylglycerol acyltransferase (PDAT) genes indicated that both acyl-CoA dependent and independent pathway regulated TAG accumulation. Therefore, this work reveals the multiple defensive mechanism for carbon metabolism in response to nitrogen starvation, which extended our understanding on the carotenoids, TAG and other important metabolites synthesis.

2.
Bioresour Technol ; 300: 122649, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896045

RESUMO

Most natural astaxanthin is fatty acid-esterified in microalgae to prevent oxidation. However, the factors influencing astaxanthin esterification (AE) are poorly understood. In this study, obstacles to AE in Coelastrum sp. HA-1 were investigated. Only half of the astaxanthin molecules in HA-1 were esterified, but AE was stimulated with exogenous linoleic acid (LA) and ethanol treatment. Astaxanthin esters and total astaxanthin (TA) with exogenous LA were elevated to 3.82-fold and 2.18-fold of control levels, respectively. Treatment with 3% (v/v) ethanol enhanced transcription of the Δ12 fatty acid desaturase gene, which caused more oleic acid (OA) to be converted to LA. Furthermore, the contents of astaxanthin esters and TA were 2.42-fold and 1.61-fold control levels, respectively. These findings confirmed that AE was upregulated by increasing LA content. Thus, a large concentration of OA alone does not increase astaxanthin accumulation in HA-1, and a certain amount of LA was necessary for AE.


Assuntos
Ácido Linoleico , Xantofilas , Esterificação , Ácidos Graxos
3.
EBioMedicine ; 51: 102566, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31901863

RESUMO

BACKGROUND: Early detection would improve upper gastrointestinal cancer prognosis. We aimed to identify serum protein biomarker for the detection of early-stage upper gastrointestinal cancer. METHODS: We performed a three-tiered study including 2028 participants from three medical centres. First, we applied two different antibody arrays to screen candidate serum proteins that increased in 20 patients with oesophageal squamous cell carcinoma (ESCC) compared with 20 normal controls. We then evaluated the selected protein by enzyme-linked immunosorbent assay in 1064 participants including 731 upper gastrointestinal cancer patients (287 ESCCs, 237 oesophagogastric junction adenocarcinomas (EJAs), and 207 stomach cancers) and 333 normal controls. The diagnostic value of the selected protein was finally validated in two independent cohorts of ESCC patients and controls (n=472 and 452, respectively). The receiver operating characteristic was used to calculate diagnostic accuracy. FINDINGS: Serum insulin-like growth factor binding protein-1 (IGFBP-1) identified in both antibody arrays showed significantly elevated levels in upper gastrointestinal cancers, compared with normal controls. Serum IGFBP-1 provided high diagnostic accuracy of early-stage ESCC, EJA, stomach and cancer (areas under the curve: 0·898, 0·936 and 0·864, respectively). This protein maintained diagnostic performance for early-stage ESCC in independent cohorts 1 and 2 (0·849 and 0·911, respectively). Additionally, serum levels of IGFBP-1 dropped significantly after surgical resection of primary tumours, compared with the corresponding pre-operative ESCC samples (p < 0·05). INTERPRETATION: Serum IGFBP-1 represents a promising diagnostic biomarker to detect early-stage upper gastrointestinal cancer.

4.
Lab Chip ; 20(1): 84-92, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31776526

RESUMO

Eccrine sweat is a rich and largely unexplored biofluid that contains a range of important biomarkers, from electrolytes, metabolites, micronutrients and hormones to exogenous agents, each of which can change in concentration with diet, stress level, hydration status and physiologic or metabolic state. Traditionally, clinicians and researchers have used absorbent pads and benchtop analyzers to collect and analyze the biochemical constituents of sweat in controlled, laboratory settings. Recently reported wearable microfluidic and electrochemical sensing devices represent significant advances in this context, with capabilities for rapid, in situ evaluations, in many cases with improved repeatability and accuracy. A limitation is that assays performed in these platforms offer limited control of reaction kinetics and mixing of different reagents and samples. Here, we present a multi-layered microfluidic device platform with designs that eliminate these constraints, to enable integrated enzymatic assays with demonstrations of in situ analysis of the concentrations of ammonia and ethanol in microliter volumes of sweat. Careful characterization of the reaction kinetics and their optimization using statistical techniques yield robust analysis protocols. Human subject studies with sweat initiated by warm-water bathing highlight the operational features of these systems.

5.
Angew Chem Int Ed Engl ; 59(1): 232-236, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31609053

RESUMO

Traditional methods for analyzing organophosphorus pesticide chlorpyrifos, usually require the tedious sample pretreatment and sophisticated bio-interfaces, leading to the difficulty for real-time analysis. Herein, we use palladium single-atom (PdSA)/TiO2 as a photocatalytic sensing platform to directly detect chlorpyrifos with high sensitivity and selectivity. PdSA/TiO2 , prepared by an in situ photocatalytic reduction of PdCl4 2- on the TiO2 , shows much higher photocatalytic activity (10 mol g-1 h-1 ) for hydrogen evolution reaction than Pd nanoparticles (1.95 mol g-1 h-1 ), and excellent stability. In the presence of chlorpyrifos, the photocatalytic activity of PdSA/TiO2 decreases. Through this inhibition effect the platform can realize a detection limit for chlorpyrifos of 0.01 ng mL-1 , much lower than the maximum residue limit (10 ppb) permitted by the U.S. Environmental Protection Agency.

6.
Ann Transl Med ; 7(20): 548, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31807530

RESUMO

Background: Serum lipids have been documented as prognostic biomarkers in several types of cancer, however the prognostic value of serum lipids in non-esophageal squamous cell carcinoma (non-ESCC) is not clear. The purpose of this study was to investigate the prognostic roles of serum lipids in non-ESCC and to establish a novel effective nomogram for overall survival (OS) and disease-free survival (DFS) in patients with non-ESCC. Methods: We retrospectively analyzed the prognostic values of pretreatment serum lipids, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoproteinA-I (ApoAI), and apolipoprotein B (ApoB) and three lipid derivatives: atherogenic index [AI: (TC-HDL-C)/HDL-C], THR (TG/HDL-C) and LHR (LDL-C/HDL-C) in non-ESCC patients. Prognostic factors predictive of OS and DFS were determined by univariate and cox hazards analysis, and prognostic nomograms were established. The predictive power of independent prognostic factors was compared adopting time-dependent ROC. Comparisons between the nomograms and traditional TNM staging systems were evaluated using the C-index and decision curve analysis. Results: A total of 180 non-ESCC patients were recruited in this prospective study between January 2006 and December 2016. Four (cancer type, TNM stage, TC, and TG) and five (cancer type, TNM stage, TC, TG, and LDL-C) independent prognostic factors were chosen to generate the nomogram for OS and DFS, respectively. Our results showed that the area under curves (AUCs) of cancer type and TG were higher than TNM stage for OS. For DFS, however, AUCs of cancer type, TG and LDL-C were higher than the TNM stage. The C-index of the nomogram for predicting the OS was 0.69, which was significantly higher than that of TNM stage (0.58, P=0.005). In addition, for DFS, the C-index of the nomogram was significantly higher than that of the TNM stage (0.70 vs. 0.60, P=0.001). Furthermore, decision curve analysis showed that the predictive accuracy of the prognostic nomogram for OS and DFS were both higher than the TNM stage. Conclusions: Our study demonstrated that pretreatment of serum lipids based on the prognostic nomogram could be applied to predict the OS and DFS in non-ESCC patients.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31878063

RESUMO

Based on satellite remote sensing image, GIS and Fragstats, this study modeled and calculated the dynamic changes of land use, land cover and landscape patterns in Guizhou Province, China, and calculated the changes of ecosystem service values (ESVs). The impacts of the evolution of landscape patterns on the ESVs were analyzed, and reasonable policy recommendations were made. The findings are as follows: (1) In the past two decades, the area of cropland and grassland has decreased; the area of water bodies, urban and rural, industrial and mining, and residential areas has increased; the area of forestland has increased first and then decreased. (2) The two major types of landscapes, cropland and grassland, are clearly being replaced by two land types, forest land and water bodies. (3) Overall, the degree of landscape aggregation and adjacency has decreased, and the landscape heterogeneity has increased. (4) The total amount of ESV in 2000, 2008, 2013 and 2017 was 2574 × 108 Yuan RMB, 2605 × 108 Yuan RMB, 2618 × 108 Yuan RMB and 2612 × 108 Yuan RMB, respectively. The changes of landscape patterns had important impacts on the ESVs. In order to solve the problems caused by the increasingly prominent changes in the landscape patterns and improve the ESVs, it is necessary to rationally plan and allocate land resources, optimize the industrial structures, and develop effective regulatory policies.

8.
Mol Med ; 25(1): 50, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729954

RESUMO

PURPOSE: To evaluate the prognostic value of circulating tumor cells (CTCs) in nasopharyngeal carcinoma (NPC). METHODS: Cox's proportional hazards regression models were used to identify whether CTCs was a poor prognostic factor for NPC. Chi-square tests were used to analyze and compare the distribution characteristics of CTCs in NPC. ROC curve was used to estimate the cut-off point of CTCs. Kaplan-Meier survival analyses were used to observe the prognostic value of CTCs alone and in combined with Epstein-Barr Virus DNA (EBV-DNA). RESULTS: CTCs was confirmed to be an independent risk factor for poor prognosis of NPC by Cox's regression models that enrolled 370 NPC cases and took age, gender, EBV-DNA and CTCs as variables. The proportion of CTCs in stage IV NPC was statistically different from that in stage III; the cut-off point of CTCs between stage IV (288 cases) and stage III (70 cases) NPC estimated by ROC curve was 0.5. The prognosis of advanced NPC patients became worse with the increase of CTCs count. The combined detection of CTCs and EBV-DNA could better predict the prognosis of NPC compared with the single detection of EBV-DNA.

9.
Int Psychogeriatr ; : 1-9, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31630703

RESUMO

BACKGROUND: Depression often coexists with other chronic conditions in older people. The COACH study is an ongoing random controlled trial (RCT) to test the effectiveness of a primary-care-based collaborative care approach to treat co-morbid hypertension and depression in Chinese rural elders. In the COACH model, a team-village doctor (VD), aging worker (AW), and psychiatrist consultant-provides collaborative care to enrolled subjects in each intervention village for 12 months. This study examines how COACH was implemented and identifies facilitators and barriers for its more widespread implementation. METHODS: Five focus groups were conducted, two with VDs, two with AWs, and one with psychiatrists, for a total of 38 participants. Transcripts were analyzed using qualitative content analysis. RESULTS: COACH care-team members showed shared understanding and appreciation of the team approach and integrated management of hypertension and depression. Team collaboration was smooth. All members regarded COACH to be effective in reducing depressive symptoms and improving patient health. Facilitators to implementation include training, leaders' support, geographic proximity between VD and AW pairs, preexisting relationships among care-team members, comparability of COACH activities and existing practices of VDs and AWs, and care team members' caring about older members of their villages. Barriers to sustainability include frustration of some VDs related to their low wages and feelings of overload of some AWs. CONCLUSIONS: COACH was positively perceived and successfully implemented. The findings offer guidance for planning primary-care-based collaborative depression care in low- and middle-income countries.

10.
ACS Appl Mater Interfaces ; 11(40): 36800-36806, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31539219

RESUMO

The oxygen vacancy profile in LaCoO3 exhibits rich phases with distinct structures, symmetries, and magnetic properties. Exploration of the lattice degree of freedom of LaCoO3 in the transition between these different structural phases may provide a route to enable new functionality in oxide materials with potential applications. To date, the oxygen vacancy profile transition in LaCoO3 has mainly been induced by transition-metal doping or thermal treatment. Epitaxial strain was proposed to compete with the lattice degree of freedom but has not yet been rationalized. Here, the experimental findings of strain-inhibited structural transition from perovskite to brownmillerite during the electromigration of oxygen vacancies in epitaxial LaCoO3 thin films are demonstrated. The results indicate that the oxygen vacancy ordering phase induced by the electric field is suppressed locally by both epitaxial strain field and external loads shown by in situ aberration-corrected (scanning)/ transmission electron microscopy. The demonstrated complex interplay between the electric and strain fields in the structural transitions of LaCoO3 opens up prospects for manipulating new physical properties by external excitations and/or strain engineering of a substrate.

11.
Aging (Albany NY) ; 11(18): 7880-7898, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31548434

RESUMO

Liquid storage of spermatozoa is important for artificial insemination and herd genetic breeding. However, the extended time of storage inducing the rapid decline in spermatozoa quality limits the development of this technology. The molecular mechanisms underlying liquid storage of spermatozoa remain largely unexplored. In this study, the effects of liquid storage on functional quality of spermatozoa were assessed in goat (Capra hircus). The time-dependent decline in spermatozoa motility showed a strong correlation with the significant increase in apoptosis. Moreover, apoptosis-related ultrastructural changes were observed, especially the defects in mitochondria. A significant decrease in mitochondrial membrane potential and changes in the expression of mitochondrial apoptosis-related proteins indicated mitochondrial dysfunction and mitochondrial apoptotic pathway activation. Notably, the abnormally high level of reactive oxygen species (ROS) caused by liquid storage resulted in oxidative damage to mitochondria and accelerated mitochondria-dependent apoptosis, as demonstrated by the addition of ROS scavenger N-acetylcysteine. Furthermore, critical differentially expressed proteins involved in mitochondria-dependent apoptosis and antioxidant defense were identified and profiled by quantitative proteomic analysis, facilitating the understanding of molecular regulation of ROS-induced mitochondria-dependent apoptosis. These outcomes provide insights into the mechanisms underlying liquid storage of goat spermatozoa and enhance the progress of semen storage technology.

12.
Int J Biol Sci ; 15(9): 1977-1992, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31523198

RESUMO

Background: Currently, there are no molecular biomarkers for the early detection of non-small-cell lung cancer (NSCLC). This study focused on identifying RNAs found on tumor-educated blood platelets (TEPs) for detecting stage I NSCLC. Methods: Platelet RNAs, isolated from the blood of 9 patients with NSCLC (stages I and II) and 8 healthy controls, were analyzed using RNA-seq. ITGA2B was selected as a candidate marker. Two different Polymerase Chain Reactions (PCR) were used to measure ITGA2B in platelet samples from healthy controls (n = 150), patients with NSCLC (n = 243), and patients with benign pulmonary nodules (n = 141) in two cohorts. Results: Platelet ITGA2B levels were significantly higher (p < 0.001) in patients with NSCLC than in all controls. The diagnostic accuracy of ITGA2B was area under the curve (AUC) of 0.922 [95% confidence interval (CI), 0.892-0.952], sensitivity of 92.8%, and specificity of 78.6% in the test cohort and 0.888, 91.2%, and 56.5% in the validation cohort for NSCLC by quantitative real time PCR (q-PCR). Furthermore, ITGA2B maintained diagnostic accuracy for patients with NSCLC using Droplet Digital PCR (ddPCR) and the other type of internal control, Ribosomal Protein L32 (RPL32) [ddPCR: 0.967 (0.929-1.000) and RPL32: 0.847(0.773-0.920)]. A nomogram incorporating ITGA2B, carcinoembryonic antigen (CEA) and stage could predict the overall survival (C-index = 0.756). Conclusions: TEP ITGA2B is a promising marker to improve identification of patients with stage I NSCLC and differentiate malignant from benign lung nodules.

13.
Front Aging Neurosci ; 11: 212, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474850

RESUMO

Objectives: To explore the transfer effects of cognitive training on working memory among older Chinese adults with mild cognitive impairment (MCI). Methods: Sixty-two MCI participants aged more than 60 years old were recruited by holding recruitment sessions in communities in China [33 for cognitive training, and 29 for mental leisure activities (MLA) control]. Cognitive functions, including working memory, execution function, reasoning ability, verbal ability, ability of daily living, were measured at three time-points (baseline, post-training and 3 months after training). Results: Compared to the MLA control, the cognitive training group showed significant effects in both the trained (working memory) and untrained (execution function and ability of daily living) domains. The effects of cognitive training on overall cognitive function, working memory and daily life ability of daily living of MCI could be maintained for at least 3 months, even without the cognitive training. Besides, complete mediating effects of cognitive training were found in executive function through working memory and working memory in ability of daily living though executive function, which suggests the presence of transfer effect of cognitive training. Conclusions: The present study supported that cognitive training could effectively improve working memory in elders with MCI. The training effects on working memory could transfer to other untrained areas (such as executive function), which also improved the comprehensive ability (ability of daily living). And the effects of training could largely persist for 3 months.

14.
J Am Chem Soc ; 141(36): 14451-14459, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31432675

RESUMO

Searching for viable strategies to accelerate the catalytic cycle of glycoside hydrolase family 7 (GH7) cellobiohydrolase I (CBHI)-the workhorse cellulose-degrading enzymes, we have performed a total of 12-µs molecular dynamics simulations on GH7 CBHI, which brought to light a new mechanism for cellobiose expulsion, coined "claw-arm" action. The loop flanking the product binding site plays the role of a flexible "arm" extending toward cellobiose, and residue Thr389 of this loop acts as a "claw" that captures cellobiose. Five mutations of residue Thr389 were considered to enhance the loop-cellobiose interaction. The lysine mutant was found to significantly accelerate cellobiose expulsion and facilitate polysaccharide-chain translocation. Lysine mutation of Thr393 in Talaromyces emersonii CBHI (TeCel7A) performed similarly. Lysine approaches the catalytic area and stabilizes the Michaelis complex, potentially affecting glycosylation, the rate-limiting step of the catalytic cycle. QM/MM calculations indicate that lysine replacement diminishes the barrier against proton transfer, the crucial step of glycosylation, by 2.3 kcal/mol. Experimental validation was performed using the full-length wild-type (WT) of TeCel7A and its mutants, recombinantly expressed in Pichia pastoris, to degrade the substrates. Compared with the WT, the lysine mutant revealed an associated higher enzymatic reaction rate. Furthermore, cellobiose yield was also increased by lysine mutation, indicating that dissociation of the enzyme from cellulose was accelerated, which largely stems from the enhanced flexibility of the "arm". The present work is envisioned to help design strategies for improving enzymatic activity, while decreasing enzyme cost.

15.
Am Psychol ; 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31393143

RESUMO

The integration of behavioral health in primary care is critical for addressing worldwide concerns for access to, and quality of, health care services for physical and mental health promotion, prevention, and disease management. Clearly, promoting knowledge exchange internationally is critical to progress. In late 2015, the American Psychological Association convened an interdisciplinary summit on global approaches to integrated health care, bringing together 82 health care professionals (nurses, primary care physicians, psychologists, psychiatrists, and social workers) and scholars from diverse disciplines in medicine, psychology, economics, health policy, public health, and demography; participants came from 10 countries. The Global Summit provided an opportunity to share best practices and innovation in patient-centered integrated health care internationally. In this article, Global Summit participants from different countries reflect on the recommendations for future interprofessional endeavors across the following themes: build international interprofessional communities for change; advocate for, and promote social equity with, a population health and patient focus; advance research and program evaluation in integrated care; advance interprofessional training and education in integrated care; and develop financially sustainable models for integrated primary care. Building upon these recommendations and reflecting on current advancement in health care policy and integrated care research, new directions are suggested for clinicians, researchers, administrators, and policymakers working toward the advancement of integrated care to improve health care services globally. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

16.
Otol Neurotol ; 40(9): 1246-1252, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31469797

RESUMO

HYPOTHESIS: The characteristics of auditory brainstem response (ABR), electrocochleogram (ECochG), and distortion product otoacoustic emissions (DPOAE) of different degrees of selective outer hair cells (OHCs) loss may be helpful for clinicians to evaluate the pathogeny, diagnosis, and rehabilitation of individuals' hearing loss. BACKGROUND: How many OHCs are necessary to maintain cochlear amplifier function remains unknown. The electrophysiologic characteristics may indicate different degrees of OHCs loss. METHODS: Electrophysiological characteristics were tested using 8-kHz pure-tone stimulus and OHCs counted specifically in the region of the cochlea corresponding to 8-kHz. Rat models of selective OHCs loss were established by injecting kanamycin (KM) at various dosages, and the region of 8-kHz was obtained by 8-kHz pure-tone exposure. RESULTS: The ABR thresholds were affected slightly with OHCs loss < 30%, and were increased dramatically with OHCs loss ranging from 30 to 70%, but the thresholds did not increase further when OHCs loss exceeded 70%. As OHCs loss increased, the compound action potential (CAP) amplitude decreased. The CAP amplitude and OHCs loss were negatively correlated. Moreover, the summating potential (SP)/action potential (AP) increased as OHCs loss increased. DPOAE and cochlear microphonics (CM) exhibited reduced amplitudes when OHCs loss < 30%. CONCLUSIONS: Electrophysiologic characteristics may indicate different degrees of OHCs loss. While OHCs loss > 70%, the cochlear amplification may lose completely, but it is difficult to detect OHCs loss < 30%, because the ABR or DPOAE may reveal "normal" at this level. Moreover, the decreased CAP amplitude or increased SP/AP may be indicators for OHCs loss.

17.
Appl Environ Microbiol ; 85(19)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31375482

RESUMO

Schizochytrium is a promising source for the production of docosahexaenoic acid and astaxanthin. The effects of different methanol concentrations on astaxanthin, biomass, and production of the lipids, squalene, and total sterol in Schizochytrium limacinum B4D1 were investigated. Astaxanthin began to accumulate when the methanol concentration reached 3.2% and peaked at 5.6% methanol, with a 2,000-fold increase over that in the control. However, under cultivation with 5.6% methanol, the biomass, lipids, squalene, and total sterol decreased to various degrees. Transcriptomic analysis was performed to explore the effects of different methanol concentrations (0%, 3.2%, and 5.6%) on the expression profile of B4D1. Three key signaling pathways were found to play important roles in regulating cell growth and metabolism under cultivation with methanol. Five central carbon metabolism-associated genes were significantly downregulated in response to 5.6% methanol and thus were expected to result in less ATP and NADPH being available for cell growth and synthesis. High methanol conditions significantly downregulated three genes involved in fatty acid and squalene/sterol precursor biosynthesis but significantly upregulated geranylgeranyl diphosphate synthase, lycopene ß-cyclase, and ß-carotene 3-hydroxylase, which are involved in astaxanthin synthesis, thus resulting in an increase in the levels of precursors and the final production of astaxanthin. Additionally, the transcriptional levels of three stress response genes were upregulated. This study investigates gene expression profiles in the astaxanthin producer Schizochytrium when grown under various methanol concentrations. These results broaden current knowledge regarding genetic expression and provide important information for promoting astaxanthin biosynthesis in Schizochytrium IMPORTANCE Schizochytrium strains are usually studied as oil-producing strains, but they can also synthesize other secondary metabolites, such as astaxanthin. In this study, methanol was used as an inducer, and we explored its effects on the production of astaxanthin, a highly valuable substance in Schizochytrium Methanol induced Schizochytrium to synthesize large amounts of astaxanthin. Transcriptomic analysis was used to investigate the regulation of signaling and metabolic pathways (mainly relative gene expression) in Schizochytrium grown in the presence of various concentrations of methanol. These results contribute to the understanding of the underlying molecular mechanisms and may aid in the future optimization of Schizochytrium for astaxanthin biosynthesis.

18.
Nano Lett ; 19(8): 5070-5076, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31322902

RESUMO

Phonon polaritons hold potential prospects of nanophotonic applications at the mid- and far-infrared wavelengths. However, their experimental investigation in the far-infrared range has long been a technical challenge due to the lack of suitable light sources and detectors. To obviate these difficulties, here we use an electron probe with sub-10 meV energy resolution and subnanometer spatial resolution to study far-infrared surface phonon polaritons (∼50-70 meV) in ZnO nanostructures. We observe ultraslow propagation and interference fringes of propagating surface phonon polaritons and obtain their dispersion relation through measurements in the coordinate space. By mapping localized modes in nanowires and flakes, we reveal their localized nature and investigate geometry and size effects. Associated with simulation, we show that surface phonon polariton behaviors can be well described by the local continuum dielectric model. Our work paves the way for spatial-resolved investigation of surface phonon polaritons by electron probes and forwards polaritonics in the far-infrared range.

19.
Front Psychol ; 10: 1549, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333552

RESUMO

Objective: Based on eastern philosophy, mindfulness is becoming popular for human being's mental health and well-being in western countries. In this study, we proposed to explore the effectiveness and potential pathway of mindfulness-based training (MBT) on Chinese Non-clinical higher education students' cognition and emotion. Methods: A paired control design was used. 48 higher education students (24 in MBT group, 24 in control group) were recruited in the study. The MBT group engaged in a 12-week MBT. A package of measurements, including sustained attention tasks (The Continuous Performance Test, CPT), executive function task (Stroop) for cognitive functions, the self-reported mindfulness levels (The Mindful Attention Awareness Scale, MAAS) and emotion (The Profile of Mood States, POMS), were apply for all participants at baseline and every 4 weeks during next 12 weeks. Results: There were no differences in baseline demographic variables between two groups. Over the 12-week training, participants assigned to MBT group had a significantly greater reduction in CPT reaction time (Cohen's d 0.72), significantly greater improvement in positive emotion (Vigor-Activity, VA) (Cohen's d 1.08) and in MAAS (Cohen's d 0.49) than those assigned to control group. And, MAAS at 4th week could significantly predict the CPT RT and VA at 8th week in the MBT group. VA at 4th week could significantly predict the CPT RT at 8th week (B = 4.88, t = 2.21, p = 0.034, R2 = 0.35). Conclusion: This study shows the efficiency of 12-week MBT on Chinese Non-clinical students' cognition and emotion. Mindfulness training may impact cognition and emotion through the improvement in mindfulness level, and may impact cognition through the improvement in positive emotion.

20.
J Colloid Interface Sci ; 554: 59-65, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279273

RESUMO

The introduction of oxygen vacancies into electrode materials has been proven to be a valid way to enhance the electrochemical performance. However, the traditional methods to introduce oxygen vacancies require severe conditions that may be harmful to hydroxides. Herein, the oxygen vacancy-rich nickel-cobalt (NiCo) layered double hydroxide (denoted as Vo-NiCo LDH) nanowire array electrode is synthesized using the chemical reduction method. Owing to the reduction of NaBH4 solution, we can create oxygen vacancies under milder conditions, thus avoiding any damage to the hydroxide. The as-synthesized electrode shows a specific capacitance of 1563.1 F g-1 at 1 A g-1, which is much higher than that of the pristine electrode (995.4 F g-1 at 1 A g-1). Moreover, the cycling performance and rate performance are also enhanced. The as-fabricated asymmetric supercapacitor (Vo-NiCo LDH//Fe2O3) is able to deliver a maximum energy density of 56.2 W h kg-1 at a power density of 800 W kg-1 with a voltage window of 1.6 V.

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