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1.
J Phys Chem Lett ; : 1419-1427, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32011143

RESUMO

Plasmonic excitations in noble metals have many fascinating properties and give rise to a broad range of applications. We demonstrate, using nonadiabatic molecular dynamics combined with time-domain density functional theory, that the chemical composition and stoichiometry of substrates can have a strong influence on charge dynamics. By changing oxygen content in TiO2, including stoichiometric, oxygen rich, and oxygen poor phases, and Ti metal, one can alter lifetimes of charge carriers in Au by a factor of 5 and control the ratio of electron-to-hole relaxation rates by a factor of 10. Remarkably, a thin TiOx substrate greatly alters charge carrier properties in much thicker Au films. Such large variations stem from the fact that the Ti and O atoms are much lighter than Au, and their vibrations are much faster at dissipating the energy. The control over a particular charge carrier and an energy range depends on the Au and TiOx level alignment, and the interfacial interaction strength. These factors are easily influenced by the TiOx stoichiometry. In particular, oxygen rich and poor TiO2 can be used to control holes and electrons, respectively, while metallic Ti affects both charge carriers. The detailed atomistic analysis of the interfacial and electron-vibrational interactions generates the fundamental understanding of the properties of plasmonic materials needed to design photovoltaic, photocatalytic, optoelectronic, sensing, nanomedical, and other devices.

2.
BMC Cancer ; 20(1): 132, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070301

RESUMO

BACKGROUND: Microvascular invasion (MVI) is an independent risk factor for poor prognosis in hepatocellular carcinoma (HCC). However, there is still a lack of preoperative markers to predict MVI in HCC. This study intends to explore the potential application value of the gamma-glutamyl transpeptidase (GGT) to lymphocyte count ratio (GLR) in predicting MVI in HCC and provide guidance for clinical diagnosis and treatment. METHODS: From March 2010 to December 2015, 230 HCC patients who underwent surgical treatment in the Affiliated Hospital of Guilin Medical University were selected. Clinicopathological parameters between the MVI group (n = 115) and the non-MVI group (n = 115) were comparatively analyzed. The GLR was used as the potential risk factor for HCC with MVI, and its optimal cut-off value was estimated by using the receiver operating characteristic (ROC) curve. The Kaplan-Meier method was used to analyze the survival of HCC patients, and univariate and multivariate Cox regression analyses were used to establish independent predictors affecting postoperative HCC patients. RESULTS: The GLR levels in the MVI group and non-MVI group were 84.83 ± 61.84 and 38.42 ± 33.52 (p <  0.001), respectively. According to ROC curve analysis, the optimal cut-off value of GLR was 56.0, and the area under the ROC curve (AUC) was 0.781 (95% CI, 0.719-0.833) for the risk prediction of MVI in HCC patients. Multivariate analysis showed that tumor size > 5 cm, HCC combined with MVI and GLR >  56.0 were independent risk factors for poor prognosis in HCC patients. In addition, compared with the non-MVI group, patients in the MVI group had shorter progression-free survival (PFS) and overall survival (OS). CONCLUSION: GLR could be a predictive biomarker of HCC after operation and a potential predictor of HCC combined with MVI.

3.
Nanoscale ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32068219

RESUMO

A structurally stable stacked multilayer carbonitride is predicted with the aid of ab initio calculations. This carbonitride consists of C3N tetrahedra, and is similar to T-carbon and thus named T-C3N. Its 2-dimensional (2D) monolayer is also carefully investigated in this work. The studies on electronic properties reveal that bulk and 2D T-C3N are insulators with a 5.542 eV indirect band gap and a 5.741 eV direct band gap, respectively. However, the monolayer T-C3N exhibits an excellent uniform porosity. Its 5.50 Å pore size is perfect for water nanofiltration. The adsorption and permeation of water molecules on the monolayer T-C3N are investigated. Its promising potential application in highly efficient nanofiltration membranes for seawater desalination is discussed.

4.
BMC Cancer ; 20(1): 144, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087687

RESUMO

BACKGROUND: Information on the optimal salvage regimen for recurrent esophageal cancer is scarce. We aimed to assess the patterns of locoregional failure, and evaluate the therapeutic efficacy of salvage therapy along with the prognostic factors in recurrent thoracic esophageal squamous cell carcinoma (TESCC) after radical esophagectomy. METHODS: A total of 193 TESCC patients who were diagnosed with recurrence after radical surgery and received salvage treatment at our hospital were retrospectively reviewed from 2004 to 2014. The patterns of the first failure were assessed. The post-recurrence survival rate was determined using the Kaplan-Meier method and analyzed using the log-rank test. Multivariate prognostic analysis was performed using the Cox proportional hazard model. RESULTS: The median time of failure was 7.0 months. Among the 193 patients, 163 exhibited isolated locoregional lymph node (LN) recurrence and 30 experienced locoregional LN relapse with hematogenous metastasis. Among the 193 patients, LN recurrence was noted at 302 sites; the most common sites included the supraclavicular (25.8%; 78/302) and mediastinal LNs (44.4%; 134/302), particularly stations 1 to 6 for the mediastinal LNs (36.4%; 110/302). The median overall survival (OS) was 13.1 months after recurrence. In those treated with salvage chemoradiotherapy, with radiotherapy, and without radiotherapy, the 1-year OS rates were 68.5, 55.0, and 28.6%; the 3-year OS rates were 35.4, 23.8, and 2.9%; and the 5-year OS rates were 31.8, 17.2, 2.9%, respectively (P < 0.001). Furthermore, patient survival in those who received salvage chemoradiotherapy was significantly better than those treated with salvage radiotherapy alone (P = 0.044). Multivariate analysis showed that the pathological TNM stage and salvage treatment regimen were independent prognostic factors. CONCLUSIONS: Supraclavicular and mediastinal LN failure were the most common types of recurrence after R0 surgery in TESCC patients. Salvage chemoradiotherapy or radiotherapy could significantly improve survival in esophageal cancer with locoregional LN recurrence.

5.
Dig Dis Sci ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034602

RESUMO

The original version of the article is missing the grant information in Acknowledgments section. Corrected version of Acknowledgments is given below.

6.
Phys Chem Chem Phys ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32057044

RESUMO

Infection by human immunodeficiency virus type 1 (HIV-1) not only destroys the immune system bringing about acquired immune deficiency syndrome (AIDS), but also induces serious neurological diseases including behavioral abnormalities, motor dysfunction, toxoplasmosis, and HIV-1 associated dementia. The emergence of HIV-1 multidrug-resistant mutants has become a major problem in the therapy of patients with HIV-1 infection. Focusing on the wild type (WT) and G48T/L89M mutated forms of HIV-1 protease (HIV-1 PR) in complex with amprenavir (APV), indinavir (IDV), ritonavir (RTV), and nelfinavir (NFV), we have investigated the conformational dynamics and the resistance mechanism due to the G48T/L89M mutations by conducting a series of molecular dynamics (MD) simulations and free energy (MM-PBSA and solvated interaction energy (SIE)) analyses. The simulation results indicate that alterations in the side-chains of G48T/L89M mutated residues cause the inner active site to increase in volume and induce more curling of the flap tips, which provide the main contributions to weaker binding of inhibitors to the HIV-1 PR. The results of energy analysis reveal that the decrease in van der Waals interactions of inhibitors with the mutated PR relative to the wild-type (WT) PR mostly drives the drug resistance of mutations toward these four inhibitors. The energy decomposition analysis further indicates that the drug resistance of mutations can be mainly attributed to the change in van der Waals and electrostatic energy of some key residues (around Ala28/Ala28' and Ile50/Ile50'). Our work can give significant guidance to design a new generation of anti-AIDS inhibitors targeting PR in the therapy of patients with HIV-1 infection.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118129, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058919

RESUMO

Simple and effective detection of thiophenols has attracted great attention. A fluorescent probe 1 with high selectivity and sensitivity is designed and synthesized based on the excited-state intramolecular proton transfer (ESIPT) in experiment. However, we conclude that the ESIPT process fails to happen actually based on the calculation results. In the present work, the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods are employed to investigate the real sensing mechanism. The calculated absorption and emission spectra agree well with the experimental results. By comparing the energy of enol and keto configurations and the constructed potential energy surfaces (PESs) in the ground (S0) and excited (S1) states of 3-(benzo[d]thiazol-2-yl)-10-butyl-10H-phenothiazin-2-ol (dye 2), the ESIPT process is confirmed impossible because of the relatively high keto form energy and potential energy barrier. Besides, the transition state of dye 2 is optimized to offer the accurate potential energy barrier. The results of calculated frontier molecular orbitals (FMOs) and spectra indicate that it is the photoinduced electron transfer (PET) process that results in the fluorescence quenching of probe 1. After adding thiophenols, the thiolysis of 2,4-dinitrophenyl ether bond is triggered and dye 2, which emits strong fluorescence because of the absence of PET process, is obtained. Consequently, our study has demonstrated that probe 1 can act as a fluorescent probe to detect thiophenols through the off-on fluorescence variation based on the PET mechanism but not the ESIPT process.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31989771

RESUMO

Materials exhibiting excitation wavelength-dependent photoluminescence (Ex-De PL) in the visible region have potential applications in bioimaging, optoelectronics and anti-counterfeiting. Herein, we report two multifunctional, chiral [Au(NHC) 2 ][Au(CN) 2 ] (NHC = (4R,5R)/(4S,5S)-1,3-dimethyl-4,5-diphenyl-4,5-dihydro-imidazolin-2-ylidene) complex double salts that display Ex-De circularly polarized luminescence (CPL) in doped polymer films and in ground powder state. Their emission maxima can be dynamically tuned from 440 to 530 nm by changing the excitation wavelength. Through both experimental and theoretical studies, we propose that the continuously tunable photoluminescence originates from multiple emissive excited states as a result of the existence of varied Au(I)···Au(I) distances in ground state. The steric properties of the NHC ligand are crucial to the tuning of Au(I)···Au(I) distances. We also demonstrate an anti-counterfeiting application using these two salts. This unique Ex-De CPL mechanism of the metal complex double salts opens a new avenue for the development of smart photoluminescence materials by manipulating noncovalent metal···metal interactions.

9.
Sci Rep ; 10(1): 711, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959854

RESUMO

Previous studies have shown that the cysteine hydropersulfide (Cys-SSH) as the sulfur donor is crucial to sulfur-containing cofactors synthesis. Recently, a selective and sensitive near-infrared ratiometric fluorescent chemosensor Cy-DiSe has been designed and synthesized to detect Cys-SSH spontaneously. Herein, by means of the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) approaches, the sensing mechanism has been thoroughly explored. According to our calculations, the experimental data have been reproduced. The results indicate the intramolecular charge transfer (ICT) is the reason for changes in fluorescence wavelengths. Compared with the chemosensor Cy-DiSe, the larger energy gap of Cy induced by ICT mechanism leads to the blue-shift of the absorption and emission spectra, which guarantees that Cy-DiSe can become a ratiometric fluorescent chemosensor to detect Cys-SSH.

10.
Neurosci Lett ; 715: 134596, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31711976

RESUMO

The occipital lobe has been implicated in anxiety disorder, however, its contributions to anxiety in healthy adults remain less clear. We conducted a resting-state functional magnetic resonance imaging study to explore the relationship between the amplitude of low-frequency fluctuation (ALFF), functional connectivity (FC), and state anxiety level in the healthy population. First, the results showed that the ALFF of the left inferior occipital gyrus (IOG) was negatively correlated with state anxiety. Furthermore, state anxiety was positively correlated with the FC between the left IOG and the right medial superior frontal gyrus and right cerebellum 8 area and negatively correlated with the FC between the left IOG and the left superior parietal gyrus. These results indicate that the occipital lobe of healthy individuals is involved in processing of anxiety in part through a frontal-parietal network.

11.
J Affect Disord ; 260: 716-721, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31563070

RESUMO

OBJECTIVE: To explore the alterations and value of brain entropy (BEN) in major depressive disorder (MDD). METHODS: 85 MDD patients and 45 matched normal controls were recruited. MDD was diagnosed based on Diagnostic and Statistical Manual of Mental Disorders, 4th ed (DSM-IV). Symptoms of depression were assessed using the Hamilton depression scale-24 (HAMD-24) at baseline and follow-up (after 8-week treatment). All subjects underwent functional magnetic resonance imaging (fMRI) scans at baseline, and 30 MDD patients completed scans at 8th week. Whole brain BEN maps at each session was calculated using the BEN mapping toolbox. RESULTS: The 8-week antidepressant treatment improved symptoms for all MDD patients. As compared to normal controls, MDD showed reduced BEN in medial orbitofrontal cortex (MOFC)/subgenual cingulate cortex (sgACC), but increased BEN in motor cortex (MC). In MDD patients, higher baseline BEN in MOFC/sgACC and lower baseline BEN in temporal cortex (TC) were associated with higher baseline HAMD scores; higher baseline BEN in MOFC/sgACC and hippocampus were associated with greater reduction of HAMD scores after 8-week medication; greater reduction of HAMD scores after 8-week medication was correlated with greater BEN reduction in MOFC/sgACC but were correlated with less BEN reduction in MC, TC, fusiform gyrus (FG) and visual cortex (VC). CONCLUSION: The results highlighted MOFC/sgACC BEN as a potential marker for the prediction of MDD diagnosis and treatment effect. MDD might have increased MOFC/sgACC BEN but reduced BEN in visual and sensory-motor circuits corresponding to the imbalanced emotional and sensory-motor information processing. Reversing this unbalanced BEN would improve disease conditions in MDD.

12.
Sci Total Environ ; 706: 135961, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31841851

RESUMO

Personal care and cosmetic products (PCPs) are the primary exposure pathway of humans to parabens and their safety has become a public concern. However, sample pretreatment of PCPs is a great challenge due to their complexities and diversity. In this study, epoxide modified molecularly imprinted polymers (MIPs) were synthesized using ethylparaben as a template, methacrylic acid and isobutyl vinyl ether as co-monomers and glycidilmethacrylate as a post-modified monomer. MIP layer open-tubular tubes were prepared by modifying branched polyethylenimine and then grafting MIPs onto the inner surface of Teflon capillary tubes. The tube was coiled to effectively increase mass transfer and coupled to an HPLC-UV system for parabens detection in PCPs. Matrix interference was significantly decreased while efficient enrichment and recoveries were obtained. Under optimized conditions, the linear range for parabens detection was 0.5-600 ng mL-1 with detection limits of 0.2 to 0.3 ng mL-1. The system was used to study the contents of parabens in popular PCPs. The concentrations of parabens in 108 PCPs ranged from <0.5 ng g-1 to 2856 µg g-1 with geometric mean of 250.3 µg g-1. Almost all of the products contained at least one kind of parabens; methyl paraben (geometric mean: 182.9 µg g-1) and n-propyl paraben (geometric mean: 42.5 µg g-1) were the predominant compounds had been found in the samples. This method could be useful for human exposure assessment towards parabens.

13.
Neurol Sci ; 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31828679

RESUMO

BACKGROUND AND PURPOSE: The role of bilirubin in patients treated with mechanical thrombectomy (MT) is unknown. We investigated the relationship between admission bilirubin levels and hemorrhagic complication in acute ischemic stroke (AIS) patients treated with MT and detailed the roles of direct bilirubin (DB), indirect bilirubin (IDB), and total bilirubin (TB). METHODS: Consecutive AIS patients treated with MT were enrolled from two stroke centers. Outcome measures included hemorrhagic transformation (HT) and symptomatic intracranial hemorrhage (sICH) within 48 h. An independent association of bilirubin with outcomes was identified by multivariate logistic regression analysis. The accuracies of bilirubin in predicting outcome were evaluated using receiver operating characteristic curve analysis. RESULTS: Of the 153 enrolled patients, 64 (41.8%) were diagnosed with HT, of which 28 (18.3%) had sICH. In univariate analyses, DB, IDB, and TB were higher in patients with HT and sICH than in patients without. After adjustment for potential confounders, DB (odds ratio [OR], 1.364; 95% confidence interval [CI], 1.133-1.641; p = 0.001), IDB (OR, 1.143; 95% CI, 1.052-1.242; p = 0.002), and TB (OR, 1.106; 95% CI, 1.041-1.175; p = 0.001) were independently associated with HT. IDB (OR, 1.177; 95% CI, 1.064-1.303; p = 0.002) and TB (OR, 1.102; 95% CI, 1.027-1.182; p = 0.007) were independently associated with sICH. Receiver operating characteristic curve analysis showed no significant difference between the three indicators of predicting HT and sICH. CONCLUSIONS: Elevated admission bilirubin is an independent predictor of HT and sICH in AIS patients treated with MT.

14.
Huan Jing Ke Xue ; 40(8): 3568-3576, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854762

RESUMO

To clarify the spatial distribution characteristics of zooplankton communities and the relationship between zooplankton and water environmental factors, 81 samples from 28 rivers and lakes in Beijing were collected in September 2017. A total of 68 species of zooplankton were identified, including 17 species of protozoa (25%), 36 species of rotifers (53%), 13 species of cladocera (19%), and copepods (3%, which were mainly copepodids and nauplii). Among 15 dominant species, 12 were copepods and rotifers. Zooplankton communities varied between the different rivers:The zooplankton in rivers in mountainous areas were mainly protozoa and copepods; in suburban areas, communities were dominated by copepods; and in urban areas, rotifers were dominant. A comprehensive water quality index, the Shannon-Wiener index, the Pielou evenness index, and the Margalef richness index were also calculated. Results showed that the water quality of the rivers in mountainous areas was generally better than in urban areas, which was better than in suburban areas. TN was found to be the main form of pollution using the single factor water quality index. Principal component analysis (PCA) and canonical correspondence analysis (CCA) identified that NH4+-N, BOD5, and COD had a significant effect on zooplankton community characteristics.


Assuntos
Rios , Zooplâncton , Animais , Pequim , Estações do Ano , Qualidade da Água
15.
Dig Dis Sci ; 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31863340

RESUMO

BACKGROUND: Gastrointestinal motility disorder is an important pathological basis for functional dyspepsia (FD). Epigastric ache and discomfort are the main symptoms of FD, and ghrelin deficiency is closely related to the occurrence and development of FD. While electroacupuncture (EA) alleviated the symptoms of FD patients and improved their quality of life, there is a lack of sufficient mechanistic evidence to support these beneficial effects. METHODS: An in vivo FD model was established in wild-type and mammalian target of rapamycin (mTOR) knockout (-/-) rats. FD rats were subjected to EA with or without mTOR agonists or inhibitors. Gastric emptying and intestinal propulsion were assessed, and pathological changes in the hypothalamus, gastric antrum, and small intestine were examined histologically. In addition, ghrelin expression and AMPK/TSC2/Rheb/mTOR activation were detected by quantitative reverse transcription polymerase chain reaction and western blot. RESULTS: EA alone or in combination with mTOR inhibitors improved gastrointestinal function in FD rats by increasing the rates of intestinal propulsion and gastric emptying, and pathological changes in the hypothalamus, gastric antrum, and small intestine were alleviated. This may be related to the significant upregulation of ghrelin expression and the effective activation of the AMPK/TSC2/Rheb/mTOR signaling pathway. Interestingly, EA also improved gastrointestinal function and ghrelin expression in mTOR (-/-) KO FD rats. CONCLUSION: Altering the level of ghrelin by regulating AMPK/TSC2/Rheb-mediated mTOR inhibition is an important way through which EA treats FD. The complex EA-mediated regulatory mechanisms of the brain-gut axis still require further exploration.

16.
J Phys Condens Matter ; 32(15): 155902, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31846949

RESUMO

By processing graphene quantum dot, an ideal semiconductor material with suitable band gap and higher electron mobility can be obtained. Thus, it has a broad prospect in the application of photoelectric response materials. Here, a graphene defect with porphyrin-like structure is selected to achieve the controlable light absorption. The double five-membered-ring parallel vacancy are based on self-healing properties of popular graphene defects. Aimed to separate exciton and hole more effectively and achieve higher photoelectric conversion efficiency, the occupied orbital and unoccupied orbital of the quantum dot with objected defect structure is taken as orderly dispersion to form an obvious charge separation state under the demonstration with first principles calculation. Most importantly, a real time real space charge separation is calculated by time-dependent ab-initio quantum dynamics based on numerical atomic basis sets. The result shows the specific graphene defects can form an efficient pure graphene photoelectric response medium like porphyrin skeleton, and the vacancy will induce to adjust and control the specific wavelength of the response light and charge separated state manipulably with odevity of number of peripheral carbon rings by the calculation of ultrafast process.

17.
BMC Med Genet ; 20(1): 197, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842790

RESUMO

BACKGROUND: We explored the association of leucine-rich repeats and calponin homology domain containing 1 (LRCH1) gene polymorphisms with genetic susceptibility to delayed encephalopathy after acute carbon monoxide poisoning (DEACMP), which might provide a theoretical basis for the pathogenesis, diagnosis, and prognosis research of DEACMP. METHODS: Four single nucleotide polymorphisms, rs1539177 (G/A), rs17068697 (G/A), rs9534475 (A/C), and rs2236592 (T/C), of LRCH1, selected as candidate genes through genome-wide association analysis, were genotyped in 661 patients (DEACMP group: 235 cases; ACMP group: 426 cases) using Sequenom Massarray®. The association analysis of four SNPs and LRCH1 was performed under different genetic models. RESULTS: LRCH1 polymorphisms (rs1539177, rs17068697, rs9534475) under additive and dominant genetic models were significantly associated with an increased risk of DEACMP, but no significant association under allele and recessive models was found. The LRCH1 rs2236592 polymorphism was susceptible to DEACMP only under the dominant model (TT/TC + CC, OR = 1.616, 95% CI: 1.092-2.390, P = 0.015784). In addition, the A allele gene of rs9534475 polymorphism in LRCH1 might increase the risk for DEACMP (OR = 1.273, 95% CI: 1.013-1.601, P = 0.038445). CONCLUSIONS: We found a significant association between the four LRCH1 polymorphisms and DEACMP. The allelic A of rs9534475 polymorphism in LRCH1 might be a risk factor for DEACMP.


Assuntos
Encefalopatias/etiologia , Encefalopatias/genética , Intoxicação por Monóxido de Carbono/complicações , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Proteínas dos Microfilamentos/genética , Polimorfismo de Nucleotídeo Único , Doença Aguda , Idoso , Alelos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Mater Sci Eng C Mater Biol Appl ; 105: 110141, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546407

RESUMO

Surface molecular imprinting for proteins, especially for the high molecular weight protein, are facing a great challenge today. We report a novel design to prepare molecular imprinting polymers (MIPs) on the surface of hemin-graphene nanosheets (H-GNs) for the recognition of thyroglobulin (Tg, 660 KD). H-GNs with an intrinsic peroxidase-like activity could effectively immobilize the protein template on its surface to improve the number of imprinted sites per unit surface area and then directly initiate free-radical polymerization to synthesize MIPs. The results indicated MIPs film could be prepared on the surface of H-GNs/filter paper, implying the advantages of surface imprinting, and exhibiting high adsorption capacity (400 mg g-1). The MIP composites clearly distinguished the proteins on the basis of the synergistic effect of shape complementarity and multiple interactions, not even anti-Tg antibodies and sample matrix. The gray intensity of the colorimetric paper-based sensor proved to be proportional to the concentration of Tg in the range of 5-100 ng mL-1 with a detection limit of 1 ng mL-1 (15 fM). The design and direct synthesis of MIPs on the H-GNs/filter paper provide a new perspective for the surface imprinting materials with potential in the recognition and detection of proteins.

19.
Front Psychiatry ; 10: 522, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396115

RESUMO

Background: Altered resting-state functional connectivity of the cerebellum in obsessive-compulsive disorder (OCD) has been previously reported. However, the previous study investigating cerebellar-cerebral functional connectivity relied on a priori-defined seeds from specific networks. In this study, we aimed to explore the connectivity alterations of the cerebellum in OCD under resting-state conditions with a hypothesis-free approach. Methods: Thirty patients with OCD and 26 healthy controls (HCs) underwent functional magnetic resonance imaging (fMRI) scanning at resting state. Regional cerebral function was evaluated by measuring the fraction of amplitude of low-frequency fluctuation (fALFF). Regions with mean fALFF (mfALFF) alterations were used as seeds in seed correlation analysis (SCA). An independent samples t test was used to compare the differences in mfALFF and functional connection (FC) between the two groups. Pearson correlation analysis was performed to identify the association between functional neural correlates and OCD symptom severity evaluated using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Results: Compared with the HC group, the OCD group showed significantly increased mfALFF values in bilateral cerebellar. The results of FC analysis showed weakened connectivity among the left Crus II, lobule VIII, and right striatum and between the right lobule VIII and the right striatum, and cingulate in the OCD group compared with the HC group. Some of the abovementioned results were associated with symptom severity. Conclusions: OCD patients showed abnormal spontaneous cerebellar activity and weakened functional connectivity between the cerebellum and the cortico-striato-thalamo-cortical (CSTC) circuit (striatum and cingulate), suggesting that the cerebellum may play an essential role in the pathophysiology of OCD.

20.
Front Neurosci ; 13: 800, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31417353

RESUMO

Near-death experiences (NDE) are episodes of enhanced perception with impending death, which have been associated with increased high-frequency (13-100 Hz) synchronization of neuronal activity, which is implicated in cognitive processes like perception, attention and memory. To test whether the NDE-associated high-frequency oscillations surge is related to cardiac arrest, recordings were made from the hippocampus of anesthetized rats dying from an overdose of the sedative chloral hydrate (CH). At a lethal dose, CH caused a surge in beta band power in CA3 and CA1 and a surge in gamma band power in CA1. CH increased the inter-regional coherence of high-frequency oscillations within and between hippocampi. Whereas the surge in beta power developed at non-lethal chloral hydrate doses, the surge in gamma power was specific for impending death. In contrast, CH strongly suppressed theta band power in both CA1 and CA3 and reduced inter-regional coherence in the theta band. The simultaneously recorded electrocardiogram showed a small decrease in heart rate but no change in waveform during the high-frequency oscillation surge, with cardiac arrest only developing after the cessation of breathing and collapse of all oscillatory activity. These results demonstrate that the high-frequency oscillation surge just before death is not limited to cardiac arrest and that especially the increase in gamma synchronization in CA1 may contribute to NDE observed both with and without cardiac arrest.

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