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1.
Chemosphere ; 240: 124937, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574441

RESUMO

Nowadays, silica nanoparticles (SiNPs) as one of the most productive nano-powder, has been extensively applied in various filed. The potential harm of SiNPs has previously received severe attention. A bulk of researches have proven the adverse effect of SiNPs on the health of ecological organisms and human. However, neurotoxic impacts of SiNPs, still remain in the stage of exploration. The potential neurotoxic effects of SiNPs need to be further explored. And the toxic mechanism needs comprehensive clarification. Herein, the neurotoxicity of SiNPs of various concentrations (100, 300, 1000 µg/mL) on adult zebrafish was determined by behavioral phenotyping and confirmed by molecular biology techniques such as qPCR. Behavioral phenotype revealed observable effects of SiNPs on disturbing light/dark preference, dampening exploratory behavior, inhibiting memory capability. Furthermore, the relationship between neurotoxic symptom and the transcriptional alteration of autophagy- and parkinsonism-related genes was preliminarily assessed. Importantly, further investigations should be carried out to determine the effects of SiNPs to cause neurodegeneration in the brain as well as to decipher the specific neurotoxic mechanisms. In sum, this work comprehensively evaluated the neurotoxic effect of small-sized SiNPs on overall neurobehavioral profiles and indicated the potential for SiNPs to cause Parkinson's disease, which will provide a solid reference for the research on the neurotoxicity of SiNPs.

2.
Front Biosci (Landmark Ed) ; 25: 283-298, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585890

RESUMO

Nlrp3 inflammasomes were shown to play a critical role in triggering obesity-associated early onsets of cardiovascular complications such as endothelial barrier dysfunction with endothelial hyperpermeability. Statins prevent endothelial dysfunction and decrease cardiovascular risk in patients with obesity and diabetes. However, it remains unclear whether statin treatment for obesity-induced endothelial barrier dysfunction is in part due to the blockade of Nlrp3 inflammasome signaling axis. The results showed that simvastatin, a clinically and widely used statin, prevented free fatty acid-induced endothelial hyperpermeability and disruption of ZO-1 and VE-cadherin junctions in mouse microvascular endothelial cells (MVECs). This protective effect of simvastatin was largely due to improved lysosome function that attenuated lysosome injury-mediated Nlrp3 inflammasome activation and subsequent release of high mobility group box protein-1 (HMGB1). Mechanistically, simvastatin induces autophagy that promotes removal of damaged lysosomes and also promotes lysosome regeneration that preserves lysosome function. Collectively, simvastatin treatment improves lysosome function via enhancing lysosome biogenesis and its autophagic turnover, which may be an important mechanism to suppress Nlrp3 inflammasome activation and prevents endothelial hyperpermeability in obesity.

3.
Acta Neurochir Suppl ; 127: 105-119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407071

RESUMO

The protein kinase RNA-like endoplasmic reticulum kinase (PERK) pathway, which is a branch of the unfolded protein response, participates in a range of pathophysiological processes of neurological diseases. However, few studies have investigated the role of the PERK in intracerebral hemorrhage (ICH). The present study evaluated the role of the PERK pathway during the early phase of ICH-induced secondary brain injury (SBI) and its potential mechanisms. An autologous whole blood ICH model was established in rats, and cultured primary cortical neurons were treated with oxyhemoglobin to mimic ICH in vitro. We found that levels of phosphorylated alpha subunit of eukaryotic translation initiation factor 2 (p-eIF2α) and activating transcription factor 4 (ATF4) increased significantly and peaked at 12 h during the early phase of the ICH. To further elucidate the role of the PERK pathway, we assessed the effects of the PERK inhibitor, GSK2606414, and the eIF2α dephosphorylation antagonist, salubrinal, at 12 h after ICH both in vivo and in vitro. Inhibition of PERK with GSK2606414 suppressed the protein levels of p-eIF2α and ATF4, resulting in increase of transcriptional activator CCAAT/enhancer-binding protein homologous protein (CHOP) and caspase-12, which promoted apoptosis and reduced neuronal survival. Treatment with salubrinal yielded opposite results, which suggested that activation of the PERK pathway could promote neuronal survival and reduce apoptosis. In conclusion, the present study has demonstrated the neuroprotective effects of the PERK pathway during the early phase of ICH-induced SBI. These findings highlight the potential value of PERK pathway as a therapeutic target for ICH.


Assuntos
Lesões Encefálicas , Hemorragia Cerebral , RNA , eIF-2 Quinase , Animais , Lesões Encefálicas/metabolismo , Hemorragia Cerebral/metabolismo , Fator de Iniciação 2 em Eucariotos , Ratos , eIF-2 Quinase/metabolismo
4.
J Behav Ther Exp Psychiatry ; 66: 101520, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675486

RESUMO

BACKGROUND AND OBJECTIVES: Attention avoidance of feedback-related stimuli is proposed to be associated with and maintain social anxiety. However, previous research has mainly focused on comparing the attention bias between two types of stimuli, while little is known about attention distribution patterns among positive, neutral, and negative feedback and non-feedback stimuli in individuals with high trait social anxiety (HSA) or low trait social anxiety (LSA). METHODS: The current study assessed eye movement pattern of participants with HSA or LSA during a speech task (high anxiety condition) or while solely watching audience feedback of the speech (low anxiety condition). A pre-recorded audience who displayed approving, neutral, or disapproving gestures was presented as feedback stimuli, while neutral facial photos were used as non-feedback stimuli. RESULTS: Only in the high anxiety condition, participants with HSA exhibited longer total fixation on non-feedback stimuli compared to those with LSA; whereas in the low anxiety condition, both groups paid more attention to emotional feedback stimuli. LIMITATIONS: The final sample size was modest due to a high suspicion rate of the reality of the audience. CONCLUSIONS: These findings suggest that only in highly anxious social situations, socially anxious individuals lack the attentional preference toward positive feedback that individuals with low anxious have.

5.
Talanta ; 206: 120199, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514856

RESUMO

A new class of intracellular signal amplification approach, integrating biodegradable manganese dioxide (MnO2) nanosheet with target-triggered DNAzyme recycling amplification in one nanosystem, was developed for highly specific and sensitive monitoring of microRNAs (miRNAs) in living cells. Briefly, the MnO2 nanosheets were employed as carrier and quencher for the hairpin-locked-DNAzyme strands (H1). Upon entering cells, the surface-adsorbed strands (H1) can be released due to the degradation of the MnO2 nanosheets by cellular glutathione. Subsequently, the hybridization reaction between target miRNAs and H1 probe induced the conformation alteration of the hairpin probes H1, formed an "active" DNAzyme. With the assistor of Mg2+, the DNAzyme was activated and induced the release of the fluorophores labeled DNA fragment, which achieved the restoration of fluorescence signal. Meanwhile, the target molecules was released and hybridized with the other H1 strand to initiate another cycle of activation, cleavage, and turnovers, which producing enhanced fluorescence signal for sensitive analysis of intracellular miRNAs. Furthermore, fluorescence imaging experiments demonstrated that the MnO2-DNAzyme nanosystem could visually detect microRNA-21 in cancer cells. The proposed strategy provides a good platform for highly sensitive detection and imaging analysis of various intracellular miRNAs in situ.

6.
J Endocrinol ; 244(1): 213-222, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31645018

RESUMO

Cerebral circulation is important in fetal brain development, and angiotensin II (Ang II) plays vital roles in regulation of adult cerebral circulation. However, functions of Ang II in fetal cerebral vasculature and influences of in utero hypoxia on Ang II-mediated fetal cerebral vascular responses are largely unknown. This study investigated the effects and mechanisms of in utero hypoxia on fetal middle cerebral arteries (MCA) via Ang II. Near-term ovine fetuses were exposed to in utero hypoxia, and fetal MCA responses to Ang II were tested for vascular tension, calcium transient, and molecular analysis. Ang II caused significant dose-dependent contraction in control fetal MCA. Ang II-induced MCA constriction was decreased significantly in hypoxic fetuses. Neither losartan (AT1R antagonist, 10-5 mol/L) nor PD123,319 (AT2R antagonist, 10-5 mol/L) altered Ang II-mediated contraction in fetal MCA. Phenylephrine-mediated constriction was also significantly weaker in hypoxic fetuses. Bay K8644 caused similar contractions between the two groups. Protein expression of L-type voltage-dependent calcium channels was unchanged. There were no differences in caffeine-mediated vascular tension or calcium transients. Contraction induced by PDBu (PKC agonist) was obviously weaker in hypoxic MCA. Protein expression of PKCß was reduced in the hypoxic compared with the control, along with no differences in phosphorylation levels. The results showed that fetal MCA was functionally responsive to Ang II near term. Intrauterine hypoxia reduced the vascular agonist-mediated contraction in fetal MCA, probably via decreasing PKCß and its phosphorylation, which might play protective effects on fetal cerebral circulation against transient hypoxia.

7.
Food Chem ; 303: 125407, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466032

RESUMO

Theaflavin (TF), which is the key pigment in black tea, is a health-promoting food component with beneficial effects on humans. However, the interactions by which these effects are transferred and exerted into protein-rich foods are unclear. Here, egg ovalbumin (OVA) was selected as a representative dietary protein to ascertain their binding mechanism. Steady-state, time-resolved fluorescence and isothermal titration calorimetric results showed that TF can interact well with OVA with an affinity magnitude of 104. The noncovalent binding was mainly driven by hydrophobic interaction and hydrogen bonds. Structural analysis displayed that the TF binding pocket significantly overlapped with one of the surrounding specific IgE-binding epitopes, thereby causing a subtle structural adjustment on the secondary conformation of OVA. The biological complexation model that was delineated here will help understand how black tea dyes egg white in tea egg products and for the development of protein-rich carriers in functional foods.


Assuntos
Biflavonoides/química , Camellia sinensis/química , Catequina/química , Clara de Ovo/química , Ovalbumina/química , Pigmentos Biológicos/química , Extratos Vegetais/química , Animais , Galinhas , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligação Proteica , Chá/química
8.
J Hazard Mater ; 383: 121132, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31518813

RESUMO

To investigate the effect of salinity (1% sodium chloride) on anaerobic microbial community structure in high strength telephthalic wastewater treatment system, the performances of anaerobic-aerobic process and the shifts of microbial community in anaerobic tank were studied and determined. Results showed that the chemical oxygen demand (COD) removal in the whole process remained above 90%. And the effluent concentrations of targeted pollutants were lower than 10 mg/L, other than para-toluic acid (PT, 38.09 mg/L). However, methane production significantly decreased compared to no salinity situation. This might be due to the inhibition of salinity on methanogens, which hindered the conversion of acetate to methane. Furthermore, the dominant genus in bacterial level changed from Tepidisphaera to Syntrophus, which facilitated the syntrophic association with hydrogenotrophic methanogens. The prevailed archaea remained acetoclastic Methanothrix above 90%. Therefore, the salinity on anaerobic microbial community structure mainly reflects in the methanogen process, remarkably decreasing methane production.

9.
Methods Mol Biol ; 2081: 219-228, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31721129

RESUMO

Bioluminescent imaging (BLI) technology has been extensively applied due to various advantages such as noninvasiveness, high sensitivity and selectivity, excellent biocompatibility and real-time visualization and monitoring. The firefly luciferase (Fluc)/luciferin system, one of the principal bioluminescent systems, has been developed as a sensor for imaging biological processes. However, a limited number of Fluc substrates hamper the further application of firefly luciferase/luciferin systems for biomedical purposes. Here we describe an approach to synthesize a series of novel luciferin substrates (cyaLucs) that produced elevated bioluminescent signals in vitro. Furthermore, we demonstrate the high efficiency of N-cyclobutylaminoluciferin (cybLuc) with high light emission and long duration in deep tissue imaging by diagnosis of cerebral tumors in vivo in a rodent model.

10.
Viruses ; 11(11)2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31684080

RESUMO

Zika virus (ZIKV) infection during pregnancy leads to severe congenital Zika syndrome, which includes microcephaly and other neurological malformations. No therapeutic agents have, so far, been approved for the treatment of ZIKV infection in humans; as such, there is a need for a continuous effort to develop effective and safe antiviral drugs to treat ZIKV-caused diseases. After screening a natural product library, we have herein identified four natural products with anti-ZIKV activity in Vero E6 cells, including gossypol, curcumin, digitonin, and conessine. Except for curcumin, the other three natural products have not been reported before to have anti-ZIKV activity. Among them, gossypol exhibited the strongest inhibitory activity against almost all 10 ZIKV strains tested, including six recent epidemic human strains. The mechanistic study indicated that gossypol could neutralize ZIKV infection by targeting the envelope protein domain III (EDIII) of ZIKV. In contrast, the other natural products inhibited ZIKV infection by targeting the host cell or cell-associated entry and replication stages of ZIKV. A combination of gossypol with any of the three natural products identified in this study, as well as with bortezomib, a previously reported anti-ZIKV compound, exhibited significant combinatorial inhibitory effects against three ZIKV human strains tested. Importantly, gossypol also demonstrated marked potency against all four serotypes of dengue virus (DENV) human strains in vitro. Taken together, this study indicates the potential for further development of these natural products, particularly gossypol, as the lead compound or broad-spectrum inhibitors against ZIKV and other flaviviruses, such as DENV.

11.
Pharmazie ; 74(10): 577-582, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685080

RESUMO

In this study, micelles were designed to deliver an antitumor agent and a fluorescent marker to a tumor site. The micelles simultaneously encapsulated epirubicin (EPI) and polyethylene glycol (PEG)-modified graphene quantum dots (GQDs-PEG), and employed a PEG-polylactic acid block copolymer amphiphilic block polymer as a nanocarrier. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to characterize the functional groups in the synthesized GQDs-PEG. A Malvern particle size meter and transmission electron microscopy were used to show that the particle size of the GQDs-PEG is approximately 2-9 nm, and that of the bifunctional EPI-loaded micelles (EPI-FIDCR) is 19.59±1.21 nm, with zeta potential at -22.87±0.85 mV. The EE% and DL% for EPI in EPI-FIDCR are 74.02±0.55 % and 3.78±0.28 %, respectively. The IC50 values of EPI-FIDCR and EPI solution (EPI-Free) for tumor cells were 7.03 µg/mL and 5.54 µg/mL, showing that EPI-FIDCR still maintained strong cytotoxicity. Fluorescence micrographs of HeLa cells incubated with GQDs-PEG and EPI-FIDCR for 6 h, respectively, show that only EPI-FIDCR could enter the cells. In vitro cellular uptake assays and an inhibition study indicated that EPI-FIDCR could deliver both EPI and GQDs-PEG into tumor cells, while maintaining an inhibitory effect similar to that of unencapsulated EPI. A pharmacokinetic study showed that EPI-FIDCR could persist in the circulation for a significant period of time. The AUC0→t calculated for the EPI-FIDCR formulation was 159.5-fold compared with that of EPI-Free, based on its improved stability and prolonged blood circulation time. The EPI-FIDCR enables both fluorescence imaging and controlled drug-release, exhibits prolonged systematic circulation time and has potential for the treatment of cancer.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31686291

RESUMO

This study used latent class analysis to examine whether multiple subgroups can be identified based on rule-breaking and aggressive behavior in school-based and at-risk adolescent samples. These groups were tested for differences in behavioral, emotional, personality and interpersonal correlates. Rule breaking and aggressive behavior co-occurred across all classes. School-based adolescents were classified as having minimal, minor or moderate antisocial problems. At-risk adolescents were classified as having mild, medium or severe antisocial problems. Generally, at-risk adolescents had higher levels of antisocial behavior, and greater severity of antisocial behavior was associated with more problems in various domains. Results differed however, for the school-based and at-risk samples with respect to emotional problems, sensation-seeking and peer conformity pressure. There is a need to jointly consider both non-aggressive rule-breaking behavior and aggressive behavior in prevention and intervention work, as it is insufficient to address isolated symptoms and problems in children and adolescents.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31688313

RESUMO

OBJECTIVES: In longitudinal studies, serum biomarkers are often measured longitudinally which is valuable to predict the risk of disease progression. Previous risk prediction models for liver cirrhosis restrict data to baseline or baseline and a single follow-up time point, which failed to incorporate the time-dependent marker information. The aim of this study is to develop risk model in patients with chronic hepatitis B for dynamic prediction of cirrhosis by incorporating longitudinal clinical data. METHODS: Data from the hospital-based retrospective cohort at the Third Affiliated Hospital of Sun Yat-sen University, from 2004 to 2016, were analyzed. Using the multilevel logistic regression model, the time-dependent marker information and individual characteristics were taken as input, and the risk of at different time as the output. RESULTS: At the end of follow-up, 8.8% of patients progressed to cirrhosis, the average estimate values of hepatitis B virus DNA and alanine aminotransferase demonstrated a downward trend, the aspartate aminotransferase/alanine aminotransferase ratio showed a flat trend overall. The important predictors were as follows: age, oral antiviral treatment, hepatitis B virus DNA. This risk prediction model had an area under the receiver operator characteristic curve of 0.835 (95% confidence interval: 0.772-0.899) and 0.809 (95% confidence interval: 0.708-0.910) in the derivation and validation sets, respectively. CONCLUSION: Longitudinal prediction model can be used for dynamic prediction of disease progression and identify changing high-risk patients.

14.
Eur J Anaesthesiol ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31688331

RESUMO

BACKGROUND: Postictal delirium (PID) is a relatively common complication following electroconvulsive therapy (ECT). OBJECTIVE: We investigated whether prophylactic dexmedetomidine administration would safely decrease the incidence of PID in psychiatric patients after ECT. DESIGN: A randomised, double-blind, placebo-controlled trial. PATIENTS: A total of 223 patients undergoing ECT were randomly allocated to two groups. INTERVENTIONS: Patients received 0.5 µg kg dexmedetomidine (Dex group, n=111) or 0.9% sodium chloride (Con group, n=112) before ECT. Propofol was used for anaesthesia and succinylcholine for muscle relaxation. The incidence of PID was measured using the Confusion Assessment Method for the Intensive Care Unit. MAIN OUTCOME MEASURES: The percentage of patients who were diagnosed with PID at any ECT session during the whole treatment. RESULTS: PID occurred in 76 (67.9%) of 112 patients given saline (0.9% sodium chloride), and in 49 (44.1%) of 111 patients given dexmedetomidine during the whole treatment. There was a significant difference in the incidence of PID between two groups (P < 0.001). Post hoc analyses showed that the incidence of PID was significantly lower in the Dex group than in the Con group from the first to the seventh ECT session (P < 0.005). There were no significant differences in seizure duration or recovery time between the two groups. Heart rate and mean arterial pressure in the Dex group were significantly lower than in the Con group at 0, 5 and 15 min after electrical stimulation. No patients developed bradycardia, hypotension or respiratory depression during recovery. CONCLUSION: Pretreatment with dexmedetomidine leads to a significant reduction in the incidence of PID with no respiratory depressant effect. Dexmedetomidine might be considered an effective method for the prevention of PID post-ECT. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR-IOR-17012306.

15.
Plant Physiol ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719152

RESUMO

Meiosis is a critical process for sexual reproduction. During meiosis, genetic information on homologous chromosomes is shuffled through meiotic recombination to produce gametes with novel allelic combinations. Meiosis and recombination are orchestrated by several mechanisms including regulation by small RNAs. Our previous work in Arabidopsis thaliana meiocytes showed that meiocyte-specific sRNAs (ms-sRNAs) have distinct characteristics, including positive association with the coding region of genes that are transcriptionally upregulated during meiosis. Here, we characterized the ms-sRNAs in two important crops, soybean (Glycine max) and cucumber (Cucumis sativus). Ms-sRNAs in soybean have the same features as those in Arabidopsis, suggesting that they may play a conserved role in eudicots. We also investigated the profiles of microRNAs (miRNAs) and phased secondary small interfering RNAs (phasiRNAs) in the meiocytes of all three species. Two conserved miRNAs, miR390 and miR167, are highly abundant in the meiocytes of all three species. In addition, we identified three novel cucumber miRNAs. Intriguingly, our data show that the previously identified phasiRNA pathway involving soybean-specific miR4392 is more abundant in meiocytes. These results showcase the conservation and divergence of ms-sRNAs in flowering plants, and broaden our understanding of sRNA function in crop species.

16.
J Ethnopharmacol ; : 112365, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31678414

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ginkgo biloba L. (Ginkgoaceae) is a traditional Chinese medicine known to treating stroke and other cardio-cerebrovascular diseases for thousands of years in China. Ginkgo diterpene lactones (GDL) attracted much attention because of their neuroprotective properties. AIM OF THE STUDY: To uncover the effects of GDL, which consist of ginkgolide A (GA), ginkgolide B (GB), and ginkgolide K (GK), on ischemic stroke, as well as the underlying molecular mechanisms. MATERIALS AND METHODS: We used middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R) models mimicking the process of ischemia/reperfusion in vivo and in vitro, respectively. Anticoagulant effects of GDL were investigated on platelet activating factor (PAF), arachidonic acid (AA) and adenosine diphosphate (ADP)-induced platelet aggregation both in vivo and in vitro. We also evaluated the effects of GDL on lipopolysaccharide (LPS)-induced inflammatory response in primary cultured rats' astrocytes. Infarct size, neurological deficit score, and brain edema were measured at 72 h after MCAO. Immunohistochemistry was utilized to analyze neurons necrosis and astrocytes activation. Expression of pro-inflammatory cytokines, including tumor necrotic factor-α (TNF-α) and interleukin-1ß (IL-1ß) were detected using enzyme-linked immunosorbent assay (ELISA) and real time PCR. The levels of toll-like receptor 4 (TLR4) and nuclear factor κB (NF-κB) were assessed by real time PCR or Western blot. RESULTS: Compared with MCAO/R rats, GDL significantly reduced infarct size and brain edema, improved neurological deficit score. Meanwhile, GDL suppressed platelet aggregation, astrocytes activation, pro-inflammatory cytokines releasing, TLR4 mRNA expression and transfer of NF-κB from cytoplasm to nucleus. Furthermore, GDL alleviated OGD/R injury and LPS-induced inflammatory response in primary astrocytes, characterized by promoting cell viability, decreasing lactate dehydrogenase (LDH) activity, and inhibiting IL-1ß and TNF-α releasing. CONCLUSIONS: In summary, GDL attenuate cerebral ischemic injury, inhibit platelet aggregation and astrocytes activation. The anti-inflammatory activity might be associated with the downregulation of TLR4/NF-κB signal pathway. Our present findings provide an innovative insight into the novel treatment of GDL in ischemic stroke therapy.

17.
Artif Cells Nanomed Biotechnol ; 47(1): 4222-4233, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31713452

RESUMO

Gold nanoparticles (AuNPs), as a kind of inorganic nanoparticle, have been gradually recognized as one of the most promising nanomaterials, which is attributed to their unique optical, electronic, sensing and biochemical characteristics. Due to such unique characteristics, AuNPs have been widely applied in biomedical fields such as diagnosis, biosensing and drug delivery. Except for their use in cancer treatment alone with their photothermal ablation of solid tumours, when used with anticancer drugs, AuNPs can exert a dual role in treating cancer. With the advantages of protecting drugs from degradation and leakage in the physiological environment, tuneable modification in size, surface and shape, and biocompatibility, AuNPs can be used as promising drug carriers in anticancer drug design. However, there are still many aspects that need to be improved during the usage of drug carriers in pharmacology including the following aspects: prolongation in the plasma, enhancement in targeting accumulation, improvement in cellular uptake and the control of intracellular release. AuNPs are important drug carriers.

18.
BMC Complement Altern Med ; 19(1): 297, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694618

RESUMO

BACKGROUND: Radix isatidis (Isatis indigotica Fort.) is an ancient medicinal herb, which has been applied to the prevention and treatment of influenza virus since ancient times. In recent years, the antioxidant activity of Radix isatidis has been widely concerned by researchers. Our previous studies have shown that Radix isatidis protein (RIP) has good antioxidant activity in vitro. In this study, the composition of the protein was characterized and its antioxidant activity in vivo was evaluated. METHODS: The model of oxidative damage in mice was established by subcutaneous injection of D-galactose for 7 weeks. Commercially available kits were used to determine the content of protein and several oxidation indexes in different tissues of mice. The tissue samples were stained with hematoxylin and eosin (H&E) and the pathological changes were observed by optical microscope. The molecular weight of RIP was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The amino acid composition of RIP was determined by a non-derivative method developed by our research group. RESULTS: RIP significantly increased the activities of antioxidant enzymes such as SOD, CAT, GSH-Px and total antioxidant capability (TAOC) but decreased the MDA level in the serum, kidney and liver. H&E stained sections of liver and kidney revealed D-galactose could cause serious injury and RIP could substantially attenuate the injury. The analysis of SDS-PAGE showed that four bands with molecular weights of 19.2 kDa, 21.5 kDa, 24.8 kDa and 40.0 kDa were the main protein components of RIP. CONCLUSIONS: The results suggested that RIP had excellent antioxidant activity, which could be explored as a health-care product to retard aging and a good source of protein nutrition for human consumption.

19.
Nano Lett ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31697502

RESUMO

Magnetic tunnel junctions (MTJs) capable of electrical read and write operations have emerged as a canonical building block for nonvolatile memory and logic. However, the cause of the widespread device properties found experimentally in various MTJ stacks, including tunneling magnetoresistance (TMR), perpendicular magnetic anisotropy (PMA), and voltage-controlled magnetic anisotropy (VCMA), remains elusive. Here, using high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy, we found that the MTJ crystallization quality, boron diffusion out of the CoFeB fixed layer, and minimal oxidation of the fixed layer correlate with the TMR. As with the CoFeB free layer, seed layer diffusion into the free layer/MgO interface is negatively correlated with the interfacial PMA, whereas the metal-oxides concentrations in the free layer correlate with the VCMA. Combined with formation enthalpy and thermal diffusion analysis that can explain the evolution of element distribution from MTJ stack designs and annealing temperatures, we further established a predictive materials design framework to guide the complex design space explorations for high-performance MTJs. On the basis of this framework, we demonstrate experimentally high PMA and VCMA values of 1.74 mJ/m2 and 115 fJ/V·m-1 with annealing stability above 400 °C.

20.
BMC Neurol ; 19(1): 274, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699038

RESUMO

BACKGROUND: Early prediction of unfavorable outcome after ischemic stroke is of great significance to the clinical and therapeutic management. A nomogram is a better visual tool than earlier models and prognostic scores to predict clinical outcomes, which incorporates different factors to develop a graphic continuous scoring system and calculates accurately the risk probability of poor outcome entirely based on individual characteristics. However, to date, no nomogram models have been found to predict the probability of 6-month poor outcome after ischemic stroke. We aimed to develop and validate a nomogram for individualized prediction of the probability of 6-month unfavorable outcome in Chinese patients with ischemic stroke. METHODS: Based on the retrospective stroke registry, a single-center study which included 499 patients from May, 2013 to May, 2018 was conducted in Nanjing First Hospital (China) for ischemic stroke within 12 h of symptoms onset. The main outcome measure was 6-month unfavorable outcome (mRS > 2). To generate the nomogram, NIHSS score on admission, Age, previous Diabetes mellitus and crEatinine (NADE) were integrated into the model. We assessed the discriminative performance by using the area under the curve (AUC) of receiver-operating characteristic (ROC) and calibration of risk prediction model by using the Hosmer-Lemeshow test. RESULTS: A visual NADE nomogram was constructed that NIHSS score on admission (OR: 1.190, 95%CI: 1.125-1.258), age (OR: 1.068, 95%CI: 1.045-1.090), previous diabetes mellitus (OR: 1.995, 95%CI: 1.236-3.221) and creatinine (OR: 1.010, 95%CI: 1.002-1.018) were found to be significant predictors of 6-month unfavorable outcome after acute ischemic stroke in Chinese patients. The AUC-ROC of nomogram was 0.791. Calibration was good (p = 0.4982 for the Hosmer-Lemeshow test). CONCLUSION: The NADE is the first nomogram developed and validated in Chinese ischemic stroke patients to provide an individual, visual and precise prediction of the risk probability of 6-month unfavorable outcome.

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