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1.
J Nanosci Nanotechnol ; 20(2): 731-740, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383068

RESUMO

NiO/ZnO gas-sensing nanotube materials were prepared by electrospinning. The structure and morphology of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energydispersive X-ray detection (EDX) and Brunauer-Emmett-Teller (BET) analysis. The template, PAN (peroxyacetyl nitrate) fibers, was completely removed, as evidenced by the EDX results. The final NiO/ZnO composite materials were composed of hexagonal wurtzite ZnO and cubic NiO and exhibited hollow tubular structures. In the composites, p-n heterojunctions were formed at the interface of NiO and ZnO. The results of gas sensitivity tests showed that the incorporation of NiO considerably improved the gas sensitivity of ZnO to ethanol. When the doping ratio was 0.125 mol/mol, the composites exhibited the highest sensitivity to ethanol (100.92 at 300 °C) and showed high selectivity.

2.
Nat Commun ; 10(1): 3917, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477733

RESUMO

Long-term stability and high-rate capability have been the major challenges of sodium-ion batteries. Layered electroactive materials with mechanically robust, chemically stable, electrically and ironically conductive networks can effectively address these issues. Herein we have successfully directed carbon nanofibers to vertically penetrate through graphene sheets, constructing robust carbon nanofiber interpenetrated graphene architecture. Molybdenum disulfide nanoflakes are then grown in situ alongside the entire framework, yielding molybdenum disulfide@carbon nanofiber interpenetrated graphene structure. In such a design, carbon nanofibers prevent the restacking of graphene sheets and provide ample space between graphene sheets, enabling a strong structure that maintains exceptional mechanical integrity and excellent electrical conductivity. The as-prepared sodium ion battery delivers outstanding electrochemical performance and ultrahigh stability, achieving a remarkable specific capacity of 598 mAh g-1, long-term cycling stability up to 1000 cycles, and an excellent rate performance even at a high current density up to 10 A g-1.

3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(4): 529-535, 2019 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-31484617

RESUMO

To investigate the effect of N-acetylcysteine(NAC)on cognitive function and nuclear factor erythroid 2 related factor 2/ heme oxygenase-1(Nrf2/HO-1)pathway in mouse models of postoperative cognitive dysfunction. Methods Fifty-four male C57BL/6J mice(3-4 months old)were randomly divided into control group,surgery group,and surgery+NAC group by block randomization.The intramedullary fixation for left tibial fracture surgery was performed to establish postoperative cognitive dysfunction models.NAC(150 mg/kg)was administered intraperitoneally in group surgery+NAC 30 minutes before and 3 hours,6 hours after surgery,while saline was given in control group and surgery group.Six mice in each group were selected randomly underwent Morris water maze test on the third day after surgery.Animals were sacrificed at the first and third postoperative days,and the hippocampus was harvested.Enzyme-linked immunosorbent assay was used to quantify the levels of interleukin-6(IL-6)and malondialdehyde(MDA)in hippocampus.Western blot and real-time polymerase chain reaction were used to measure the expressions of Nrf2 and HO-1 in hippocampus. Results There was no significant difference in swimming speed among three groups(F=2.135,P=0.114).Compared with control group and surgery+NAC group,the surgery group had prolonged escape latency(P<0.01),reduced platform crossing times(P<0.01),and shortened time spent in the target quadrant(P<0.01).Compared with the control group,the surgery group and the surgery+NAC group had significantly increased levels of IL-6 and MDA in hippocampus at the first postoperative day(all P=0.000).On the third postoperative day,there was no significant difference in the levels of IL-6(P=0.251)and MDA(P=0.103)between control group and surgery+NAC group.The protein expressions of Nrf2 and HO-1 in hippocampus were significantly higher in surgery group and surgery+NAC group than in control group and significantly higher in surgery+NAC group than in surgery group(all P=0.000).The mRNA expressions of Nrf2 and HO-1 in hippocampus were significantly higher in surgery group and surgery+NAC group than in control group and significantly higher in surgery+NAC group than in surgery group (all P=0.000). Conclusions NAC pretreatment may reduce oxidative stress and inflammatory response in hippocampus and improve cognitive function.Such effect may be relate to the activation of Nrf2/HO-1 pathway.

4.
Aust N Z J Psychiatry ; : 4867419872248, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486343

RESUMO

OBJECTIVE: Since only 30% or fewer of individuals at clinical high risk convert to psychosis within 2 years, efforts are underway to refine risk identification strategies to increase their predictive power. The clinical high risk is a heterogeneous syndrome presenting with highly variable clinical symptoms and cognitive dysfunctions. This study investigated whether subtypes defined by baseline clinical and cognitive features improve the prediction of psychosis. METHOD: Four hundred clinical high-risk subjects from the ongoing ShangHai At Risk for Psychosis program were enrolled in a prospective cohort study. Canonical correlation analysis was applied to 289 clinical high-risk subjects with completed Structured Interview for Prodromal Syndromes and cognitive battery tests at baseline, and at least 1-year follow-up. Canonical variates were generated by canonical correlation analysis and then used for hierarchical cluster analysis to produce subtypes. Kaplan-Meier survival curves were constructed from the three subtypes to test their utility further in predicting psychosis. RESULTS: Canonical correlation analysis determined two linear combinations: (1) negative symptom and functional deterioration-related cognitive features, and (2) Positive symptoms and emotional disorganization-related cognitive features. Cluster analysis revealed three subtypes defined by distinct and relatively homogeneous patterns along two dimensions, comprising 14.2% (subtype 1, n = 41), 37.4% (subtype 2, n = 108) and 48.4% (subtype 3, n = 140) of the sample, and each with distinctive features of clinical and cognitive performance. Those with subtype 1, which is characterized by extensive negative symptoms and cognitive deficits, appear to have the highest risk for psychosis. The conversion risk for subtypes 1-3 are 39.0%, 11.1% and 18.6%, respectively. CONCLUSION: Our results define important subtypes within clinical high-risk syndromes that highlight clinical symptoms and cognitive features that transcend current diagnostic boundaries. The three different subtypes reflect significant differences in clinical and cognitive characteristics as well as in the risk of conversion to psychosis.

5.
Brain Imaging Behav ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31478145

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disease in elderly individuals. We conducted this study to examine whether alterations in the fractional amplitudes of low-frequency fluctuations (fALFF) in the AD spectrum were frequency-dependent and symptom-relevant. A total of 43 patients with subjective cognitive decline (SCD), 52 with amnestic mild cognitive impairment (aMCI), 44 with Alzheimer's dementia (d-AD) and 55 well-matched controls participated in resting-state functional magnetic resonance imaging (rs-fMRI) scans. The amplitudes were measured using fALFF within the slow-4 (0.027-0.073 Hz) and slow-5 (0.01-0.027 Hz) bands. Repeated-measures analysis of variance was performed on fALFF within two bands and correlated with neuropsychological test scores. The significant main effects of frequency and group on fALFF differed widely across brain regions. There were more varied areas in the slow-5 band than the slow-4 band. The fALFF associated with primary disease effects was mainly distributed in the parietal lobe. Obvious frequency band and group interaction effects were observed in the left angular gyrus, left calcarine fissure and surrounding cortex, left superior cerebellum, left cuneus and right lingual gyrus. Neuropsychological tests scores were significantly correlated with the fALFF magnitude of the left cuneus and right lingual in the slow-5 band. Our results suggested that the AD continuum had abnormal amplitudes in intrinsic brain activity, and these abnormalities were frequency-dependent and mainly associated with the slow-5 band rather than the slow-4 band. This may guide the frequency choice of future rs-fMRI studies and provide new insights into the neuropathophysiology of AD.

6.
Hum Mutat ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31479177

RESUMO

The typical phenotype of arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome involves three cardinal symptoms as the name describes, harboring biallelic mutations on VPS33B or VIPAS39. Except for ARC syndrome, low gamma-glutamyltransferase (GGT) cholestasis often implies hereditary hepatopathy of different severity; however, some remain undiagnosed. Several monogenic defects typically with multiorgan manifestations may only present liver dysfunction at times, such as DGUOK defect and AGL defect. Previously, four VPS33B mutated cases were reported without arthrogryposis, or with less severe symptoms and longer lifespan, indicating the possibility of incomplete ARC phenotype of isolated hepatopathy. So we retrospectively reviewed all patients with confirmed VPS33B/VIPARS39 defect in our center and identified three presenting isolated low-GGT cholestasis with intractable pruritus. Distinguished from others with typical ARC phenotype, these patients did not suffer the other two typical characteristics, survived much longer, and shared a novel missense VPS33B variation c.1726T>C, p.Cys576Arg, causing declined protein expression and abolished interaction with VIPAS39 in-vitro. Serum bile acid profiles of our VPS33B/VIPAS39 mutated patients revealed similar changes to primary defect of bile salt export pump, among which those with isolated cholestasis phenotype had a higher level of total secondary bile acids than that with typical ARC phenotype, indicating the partial residual function of VPS33B.

7.
J Cosmet Dermatol ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31479196

RESUMO

BACKGROUND: Melasma is a benign and chronic hypermelanosis characterized by irregular light brown to dark brown patches of hyperpigmentation on the skin. Oral tranexamic acid (TA) or vitamin C (VC) supplementation has been one treatment choice. TA interferes with keratinocyte-melanocyte interactions, and VC functions by reducing melanin production resulting in skin rejuvenation and whitening. AIM: The aim of the present study was to compare the efficacy and safety of Myjet assisted transdermal injection of TA vs VC in the treatment of melasma. METHODS: In this split-face controlled trial, 17 patients were randomized to receive eight weekly transdermal injections of TA or VC via Myjet either on the right or the left side of their face. MASI was measured from each side of the face at the baseline, at the middle, and at the end of treatment. RESULTS: A reduction in MASI was observed for TA and VC separately (P value < 0.05). The difference in efficacy between TA and VC group was not statistically significant (P value 0.05). Both treatments were well tolerated, with no serious adverse events reported. CONCLUSION: Weekly TA or VC transdermal injections can be an effective treatment for melasma. Further studies are required to validate these findings.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31480140

RESUMO

Objective: To develop healthier comminuted meat products to meet consumer demand, the gel properties, rheological properties, microstructure and water distribution of pork meat batters formulated with various amounts of bamboo shoot dietary fiber (BSDF) were investigated. Methods: Different levels of BSDF (0-4%) were added to pork batters, and the pH, color, water-holding capacity, texture and rheological properties of pork batters were determined. Then, pork batters were analyzed for their microstructure and water distribution using scanning electron microscopy (SEM) and low-field nuclear magnetic resonance (LF-NMR). Results: Compared with the control, BSDF addition into meat batters showed a significant reduction in L*-value and a significant increase in b*-value (P<0.05). BSDF addition of up to 4% reduced the pH value of pork batters by approximately 0.15 units; however, the cooking loss and expressible water loss decreased significantly (P<0.05) with the increased addition of BSDF. The hardness and gel strength were noticeably enhanced (P<0.05) as the content of BSDF increased. The rheological results showed that BSDF added into pork batters produced higher storage modulus (G') and loss modulus (G'') values. The SEM images suggested that the addition of BSDF could promote pork batters to form a more uniform and compact microstructure. The proportion of immobilized water increased significantly (P<0.05), while the population of free water was decreased (P<0.05), indicating that BSDF improved the water-holding capability of pork batters by decreasing the fraction of free water. Conclusion: BSDF could improve the gel properties, rheological properties and water distribution of pork meat batters and decrease the proportion of free water, suggesting that BSDF has great potential as an effective binder in comminuted meat products.

9.
PLoS One ; 14(9): e0222192, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31491020

RESUMO

The integral role of sleep in cognition, such as night-time sleep and napping duration, has yielded mixed findings, especially in healthy elderly adults. This study aimed to identify the heterogeneous classes of the cognitive trajectories and investigated the associations between sleep parameters and the trajectories of cognition in different elderly subpopulations. The study was based on a large, national representative sample aged 60 years or older. Two cognitive measures were assessed, including executive function and episodic memory. Sleep parameters were evaluated, including post-lunch napping, night-time sleep duration, and sleep disturbances. Latent growth mixture model (LGMM) was used to describe the trajectories of cognition and investigate the effects of sleep factors on cognition. Three heterogeneous trajectories were identified for executive cognition and four for episodic memory. Inverted U-shape associations of cognition with night-time sleep and napping duration were found. In LGMM, night-time sleep duration was negatively associated with the baseline episodic memory in elderly adults. Post-lunch napping was positively associated with the baseline executive function (ß = 0.078, P<0.05) and episodic memory (ß = 0.084, P<0.05) in men, whereas it was only associated with impaired episodic memory (ß = -0.152, P<0.05) in women. Frequent sleep disturbances were only associated with the impaired executive function at baseline (ß = -0.088, 95%CI -0.162, -0.013) among older men. Overall, sleep parameters played different roles in heterogeneous trajectories of cognition by sex difference. Sleep factors may not be related to the rate of cognition decline, but these factors, independent of time-variant depressive symptoms, were associated with the initial status of cognition at baseline.

10.
PLoS One ; 14(9): e0222135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31487326

RESUMO

OBJECTIVE: To investigate the association of bilateral high-frequency hearing loss (BHFHL) with blood pressure and hypertension among occupational noise exposed workers. METHODS: Occupational noise exposed workers were enrolled in 2017 from the occupational diseases survey of Chengdu. BHFHL was classified as normal, mild, or high by the bilateral high-frequency tone average. Linear regression model was used to assess the effects of occupational noise exposure time and BHFHL on blood pressure. Logistic regression model was performed to estimate hypertension risk odds ratios (ORs) associated to occupational noise exposure time and BHFHL. RESULTS: Increasing years of occupational noise exposure and BHFHL were significantly associated with systolic and diastolic blood pressure increase (all P<0.001). The lineal trend was only significant in males, with adjusted ORs for hypertension gradually increasing with increasing years of occupational noise exposure (P<0.001). Furthermore, subjects having mild and high BHFHL had a higher hypertension risk of 34% and 281%, respectively (both P<0.001). Dose-response relationship between BHFHL and hypertension was found in both males and females. CONCLUSIONS: Occupational noise exposure was positively associated with blood pressure levels and hypertension risk.

11.
Ren Fail ; 41(1): 814-820, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31488010

RESUMO

Objective: To study the efficacy and safety of sustained low-efficiency diafiltration (SLEDf) versus hemodialysis (HD) for patients with wasp stings who developed stage III acute kidney injury (AKI). Methods: We retrospectively analyzed the clinical data of consecutive patients who developed AKI following wasp stings. All eligible patients received renal replacement therapy in combination with hemoperfusion. Thereafter, blood purification therapy and HD were performed with a volumetrically controlled machine and 1.7 m2 surface, Fresenius Polysulfone HD filter and SLEDf was undertaken with a volumetrically controlled machine and 1.3 m2 surface, Fresenius Polysulfone HD filter. Results: Forty patients developed stage III AKI following wasp stings, including 14 patients that received SLEDf and 26 patients underwent HD. Thirteen patients were aged less than 60 years and underwent HD (group I), 27 patients were aged at least 60 years, including 13 patients undergoing HD (group II) and 14 patients receiving SLEDf (group III). Groups I and II completed 150 and 162 sessions of HD, respectively, and group III completed 156 sessions of sustained low-efficiency blood purification therapy, including 50 sessions of SLEDf. The time to return to normal serum creatinine levels was 38.8 ± 2.7 days for group I, 47.2 ± 5.3 days for group II, and 39.2 ± 3.3 days for group III. A statistically significant difference was observed in time to normal serum creatinine levels among the three groups. Conclusion: Elderly wasp victims have more severe illness than younger wasp victims and SLEDf is safe and superior to HD in recovery of renal function of elderly wasp victims.

12.
Biomed Environ Sci ; 32(8): 571-577, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31488233

RESUMO

OBJECTIVE: The aim of this study was to determine whether low calf circumference (CC) could predict nutritional risk and the cutoff values of CC for predicting nutritional risk in hospitalized patients aged ⪖ 80 years. METHODS: A total of 1,234 consecutive patients aged ⪖ 80 years were enrolled in this study. On admission, demographic data, CC, and laboratory parameters were obtained. Patients with Nutritional Risk Screening 2002 (NRS-2002) total score ⪖ 3 were considered as having nutritional risk. RESULTS: CC values were significantly lower in patients with nutritional risk compared to those in patients without nutritional risk [27.00 (24.50-31.00) vs. 31.00 (29.00-33.50], P < 0.001]. CC was negatively correlated with age and nutritional risk scores. Logistic regression analysis of nutritional risk revealed that body mass index, albumin level, hemoglobin level, cerebral infarction, neoplasms, and CC (OR, 0.897; 95% confidence interval, 0.856-0.941; P < 0.001) were independent impact factors of nutritional risk. Nutritional risk scores increased with a decrease in CC. In men, the best CC cutoff value for predicting nutritional risk according to the NRS-2002 was 29.75 cm. In women, the cutoff value was 28.25 cm. CONCLUSION: CC is a simple, noninvasive, and valid anthropometric measure to predict nutritional risk for hospitalized patients aged ⪖ 80 years.

13.
Mol Cancer Ther ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488699

RESUMO

Multidrug resistance and tumor migration and invasion are still the main obstacles to effective breast cancer chemotherapies. Transgelin 2 has recently been shown to induce drug resistance, tumor migration, and invasion. The aim of this study was to determine the biological functions of Transgelin 2 and the mechanism underlying how Transgelin 2 induces paclitaxel (PTX) resistance and the migration and invasion of breast cancer. We detected that the protein level of Transgelin 2 was significantly up-regulated in breast cancer tissues compared with adjacent nontumor tissues. A bioinformatics analysis indicated that Transgelin 2 was significantly related to clinicopathological parameters and patient prognosis. Overexpression of Transgelin 2 enhanced the migration and invasion of human breast cancer cells and decreased the sensitivity of breast cancer cells to paclitaxel. Meanwhile, the tumorigenesis and metastasis of breast cancer cells were also enhanced by Transgelin 2 overexpression in vivo. Moreover, Transgelin 2 overexpression activated the PI3K/Akt/GSK-3ß pathway by increasing the phosphorylation levels of Akt and GSK-3ß and decreasing the expression of PTEN. We also found that Transgelin 2 could directly interact with PTEN and was located upstream of PTEN. Furthermore, the PI3K/Akt pathway inhibitor MK-2206 reversed the resistance to paclitaxel and inhibited the migration and invasion of breast cancer cells. These findings indicate that Transgelin 2 promotes paclitaxel resistance and the migration and invasion of breast cancer by directly interacting with PTEN and activating the PI3K/Akt/GSK-3ß pathway. Transgelin 2 may therefore be useful as a novel biomarker and therapeutic target for breast cancer.

14.
Avian Pathol ; : 1-36, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31508993

RESUMO

The H7 subtype avian influenza virus (AIV) has been reported to infect not only poultry but also humans. The hemagglutinin (HA) protein is the major surface antigen of AIV and plays an important role in viral infection. In this study, five monoclonal antibodies (mAbs) against the HA protein of H7 virus, 2F8, 3F6, 5C11, 5E2 and 5C12, were produced and characterized. Epitope mapping indicated that 103RESGSS107 was the minimal linear epitope recognized by the mAbs 2F8/3F6/5C11, and the other mAbs, 5E2/5C12, recognized the epitope 103-145aa. The protein sequence alignment of HA indicated that the two epitopes were not found in other subtypes of AIV, and all five mAbs did not cross-react with other subtypes, suggesting these mAbs are specific to H7 virus. The epitope 103RESGSS107 was highly conserved among Eurasian lineage strains of H7 AIV, whereas three amino acid substitutions (E104R, E104 K and E104G) in the epitope occurred in 98.44% of North-American lineage strains. Any of these single mutations led the mutated epitope not to be recognized by mAbs 2F8/3F6/5C11; thus, these mAbs can distinguish between Eurasian and North-American lineages of H7 strains. Furthermore, the mAbs 2F8, 3F6 and 5C11 could be highly blocked with H7-positive serum in blocking assays, revealing that 103RESGSS107 may be a dominant epitope stimulating the production of antibodies during viral infection. These results may facilitate future investigations into the structure and function of HA protein, as well as surveillance and detection of H7 virus. RESEARCH HIGHLIGHTS Five mAbs against HA protein of H7 AIV were generated and characterized Two novel epitopes 103RESGSS107 and 103-145aa were identified The epitope 103RESGSS107 differs between Eurasian and North-American lineage The mAbs 2F8, 3F6 and 5C11 could distinguish two lineages of H7 strains.

15.
Chin J Nat Med ; 17(7): 551-560, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31514987

RESUMO

Ziziphi Spinosae Semen (ZSS) has been used for treatment of insomnia in China for centuries. To reveal the influence of insomnia on the levels of the neurotransmitters including serotonin (5-HT), glutamic acid (Glu), γ-aminobutyric acid (GABA), noradrenaline (NE) and dopamine (DA), and to study the role of ZSS aqueous extract in the treatment of insomnia, an UPLC-ESI- MS/MS method was developed and validated for simultaneous determination of five neurotransmitters in the rat brain. The brain samples were pretreated by one-step direct protein precipitation with acetonitrile. The analytes were detected in positive mode with multiple reaction monitoring (MRM) and the procedure was completed in less than 10 min. The method showed a good linearity (R2 > 0.9967) with the other validation parameters were within acceptance range. The results indicated that the concentration of 5-HT, GABA and DA is significantly lower (P < 0.01) in para-chlorophenylalanine (PCPA)-induced insomnia rat model group, while Glu and NE significantly higher than those in control group (P < 0.01). Treatment with ZSS aqueous extract (4 or 8 g·kg-1·d-1 for seven days) could ameliorate the symptoms of insomnia by significantly changing the levels of the neurotransmitter parameters mentioned above. The data obtained in this study demonstrate that ZSS aqueous extract could ameliorate the symptoms of insomnia by modulating the levels of monoamines and amino acid neurotransmitters in the brain.

16.
Org Lett ; 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31517497

RESUMO

A regioselective synthetic method for the preparation of indole-fused seven-membered rings and bis(indole) connected to five-membered heterocyclic units from gold(I)-catalyzed cascade cycloisomerization of bis(indolyl)-1,3-diynes is described. This divergence in product selectivity was induced by introducing another alkynyl moiety to change the electron density at the internal alkyne and fine-tuning the steric nature of the phosphine ligand in the Au(I) catalyst. Mechanistic studies including DFT calculations uncovered the ligand-controlled manner.

17.
Int J Biol Macromol ; 141: 150-160, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31487514

RESUMO

Three polysaccharides (WZP1, WZP2, WZP3) and their Se-enriched products (SeWZP1, SeWZP2 and SeWZP3) were obtained from Pleurotus ostreatus using a simple, rapid method and HNO3-Na2SeO3 method, respectively. The molecular weight distribution profiles of all samples except SeWZP2 showed double peaks. The average molecular weights (Mw) of WZP1-3 were 48.6 kDa, 20.2 kDa and 11.8 kDa, respectively, and of SeWZP1-3 were 19.6 kDa, 37.7 kDa, 14.5 kDa, respectively. The complexity of monosaccharide composition of WZP1-3 was inversely proportional to the ethanol concentration used in the ethanol precipitation process. Additionally, the results of biological activity tests indicated that α-glucosidase inhibitory activity of WZP1-3 was related to the molecular weight and the monosaccharide composition complexity. The selenized modification can improve the α-glucosidase-inhibiting, hydroxyl radical-scavenging activity of P. ostreatus polysaccharides. Therefore, by improving their bioactivities by selenization, the polysaccharides of P. ostreatus could be utilized as a natural health food supplement.

19.
J Pharm Biomed Anal ; 177: 112837, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31493746

RESUMO

The ambiguity of dose-effect relationship of many traditional Chinese medicines (TCMs) has always influenced their rational use in TCM clinic. Rhubarb, a preferred representative of cathartic TCM, is currently widely used that results in a diversity of its dosage. The aim of this study was to use an integrated metabolomics strategy to simultaneously reveal dose-effect relationship and therapeutic mechanisms of different efficacy of rhubarb in constipation rats. Six doses of rhubarb (0.135, 0.27, 0.81, 1.35, 4.05, and 8.1 g/kg) were examined to elucidate the laxative and fire-purging effects by pathological sections and UPLC-Q-TOF/MSE. The results showed that there existed serious lesions in the stomach and colon of model rats. And conditions were basically improved to some extent in rhubarb-treated groups. Through relative distance calculation based on metabolomics score plots, it suggested that the effective dose threshold (EC20-EC80 range) of rhubarb was from 0.31 to 4.5 g/kg (corresponding to 3.44-50.00 g in the clinic) in rat serum and 0.29-2.1 g/kg (corresponding to 3.22-23.33 g in the clinic) in feces. Then, 33 potential biomarkers were identified in total. Functional pathway analysis revealed that the alterations of these biomarkers were associated with 15 metabolic pathways, mainly including arachidonic acid metabolism, glycerophospholipid metabolism, steroid biosynthesis, primary bile acid biosynthesis and sphingolipid metabolism. Of note, different doses of rhubarb could alleviate endogenous disorders to varying degrees through regulating multiple perturbed pathways to the normal state, which might be in a dose-dependent manner and involved in therapeutic mechanisms. To sum up, integrated serum and fecal metabolomics obtained that rhubarb ranging from 0.31 to 2.1 g/kg is safe and effective for constipation treatment. Also, our findings showed that the robust metabolomics techniques would be promising to be more accurately used in the dose-effect studies of complex TCM, and to clarify syndrome pathogenesis and action mechanisms in Chinese medicine.

20.
Neuropsychologia ; : 107189, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31513808

RESUMO

Working memory research has primarily concentrated on studying our senses separately; the neural basis of maintaining information from multiple sensory modalities in working memory has been not well elucidated. It is debated whether multisensory information is maintained in the form of modality-specific representations or amodal representations. The present study investigated what brain regions were engaged in both types of complex audiovisual objects maintenances (semantically congruent and incongruent) using functional magnetic resonance imaging and conjunction analysis, and examined in which form to maintain multisensory objects information in working memory. The conjunction analysis showed that there was common brain regions activation involving left parietal cortex (e.g., left angular gyrus, supramarginal gyrus, and precuneus) while maintaining semantically congruent audiovisual object, while the common brain regions activation including the bilateral angular, left superior parietal lobule, and left middle temporal gyrus was found during maintaining semantically incongruent audiovisual objects. Importantly, the shared conjoint brain regions activation consists of bilateral angular gyrus and left middle frontal gyrus was observed while maintaining both types of semantically congruent and incongruent complex audiovisual objects. And these brain regions may play different role while maintaining these complex multisensory objects, such as supramodel storage per se and intentional attention. The findings of the present study may support the amodal view that working memory has a central storage system to maintain multisensory information from different sensory inputs.

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