Sex-differential cognitive performance on MCCB of youth with BD-II depression.

BACKGROUND: Recent evidences have shown sex-differential cognitive deficits in bipolar disorder (BD) and differences in cognitions across BD subtypes. However, the sex-specific effect on cognitive impairment in BD subtype II (BD-II) remains obscure. The aim of the current study was to examine whether cognitive deficits differ by gender in youth with BD-II depression. METHOD: This cross-sectional study recruited 125 unmedicated youths with BD-II depression and 140 age-, sex-, and education-matched healthy controls (HCs). The Chinese version of the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB) was used to assess cognitive functions. Mood state was assessed using the 24-item Hamilton Depression Rating Scale (24-HDRS) and the Young Mania Rating Scale (YMRS). Multivariate analysis of covariance (MANCOVA) was conducted. RESULT: ​Compared with HCs, patients with BD-II depression had lower scores on MCCB composite and its seven cognitive domains (all p < 0.001). After controlling for age and education, MANCOVA revealed significant gender-by-group interaction on attention/vigilance (F = 6.224, df = 1, p = 0.013), verbal learning (F = 9.847, df = 1, p = 0.002), visual learning (F = 4.242, df = 1, p = 0.040), and composite (F = 8.819, df = 1, p = 0.003). Post hoc analyses suggested that males performed worse in the above-mentioned MCCB tests than females in BD-II depression. CONCLUSION: Our study demonstrated generalized cognitive deficits in unmedicated youths with BD-II depression. Male patients performed more serious cognitive impairment on attention/vigilance, verbal learning, and visual learning compared to female patients.

Cognitive dysfunction and neurometabolic alternations in major depressive disorder with gastrointestinal symptoms.

BACKGROUND: Brain biochemical abnormalities have been associated with major depressive disorder (MDD) and cognitive impairments. However, the cognitive performance and neurometabolic alterations of MDD patients accompanied by gastrointestinal (GI) symptoms remain to be elucidated. We aimed to reveal the features and correlation between cognitive impairments and brain biochemical abnormalities of depressed patients with GI symptoms. METHODS: Fifty MDD patients with GI symptoms (GI group), 46 patients without GI symptoms (NGI group) and 50 demographically matched healthy controls (HCs) underwent Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB) assessments. In addition, proton magnetic resonance spectroscopy (1H-MRS) was used to obtain ratios of N-acetyl aspartate to creatine (NAA/Cr) and choline-containing compounds to creatine (Cho/Cr) in the thalamus, putamen and anterior cingulate cortex (ACC). Finally, association analysis was conducted to investigate the relationships of these measurements. RESULTS: Compared to HCs, participants in both the GI and NGI groups had significantly reduced performance in the six MCCB cognitive domains (all p < 0.05), except for reasoning and problem solving. Higher Cho/Cr ratios in the right thalamus (p < 0.05) and lower NAA/Cr ratios in the left putamen (p < 0.05) were found in the NGI group than in the GI group. The severity of GI symptoms was negatively correlated with Cho/Cr ratios in the right ACC (r = -0.288, p = 0.037). In addition, the T-scores of visual learning were negatively correlated with NAA/Cr ratios in the right ACC (r = -0.443, p = 0.001) and right thalamus (r = -0.335, p = 0.015). CONCLUSION: Our findings suggest that MDD patients with GI symptoms may exhibit greater neurometabolic alternations than those without GI symptoms, while both show similar cognitive dysfunction. In addition, neurometabolic alterations in the ACC and thalamus may underlie the neural basis of GI symptoms and cognitive impairment in MDD.

Recent Advances of NaLuF4-Based Upconversion Nanocrystals.

In recent years, lanthanide-doped upconversion nanocrystals have been developed as a new class of fluorescent probe that have become promising alternatives to organic fluorophores and quantum dots for applications in biological and medical fields. This technique offers large anti-Stokes shifts, low autofluorescence background, sharp emission bandwidths, high photochemical stability, and deep penetration depth. According to the recently reports, NaLuF4 is a better host material for lanthanide upconversion compared to the classic NaYF4 host. Some reviews concerning the upconversion nanocrystals have been reported, but no one focuses on the NaLuF4-based nanocrystals. In this review, recent reports regarding the synthesis of NaLuF4-based nanocrystals and their upconversion luminescence properties, surface modification, and biological applications are summarized.

Preparation of Novel Europium Complex Doped Ag@SiO2 Nanoparticles with Intense Fluorescence.

In this study, a new europium complex of 4,4'-bis (1",1",1",2",2",3",3"-heptafluoro-4",6"- hexanedion-6"-yl)-o-terpheny-Eu(3+)-4,7-diphenyl-1,10-phenanthroline-2,9-dicarboxylic acid-(3-aminopropyl) trimethoxysilane (BHHT-Eu(3+)-DPPDA-APTMS) was prepared first. Then novel core-shell Ag@SiO2 nanoparticles with BHHT-Eu(3+)-DPPDA-APTMS doped in shell were synthesized by a facile water-in-oil microemulsion method. The properties of the prepared complex and nanoparticles, and the effect of metal enhanced fluorescence for the nanoparticles were investigated. The prepared nanopartilces exhibited intense fluorescence, uniform morphology and good water-solubility. The fluorescent intensities of silver core-present nanopartciles were significant higher than that of silver core-absent nanoparticles owing to the metal enhanced fluorescence of silver core. It is expectable that the as-prepared nanoparticles can serve as a potential fluorescent nanoprobe, applying in high sensitive biological and medical detections.

Synthesis of NaYF4 and NaLuF4 Based Upconversion Nanocrystals and Comparison of Their Properties.

In this study, four kinds of upconversion nanocrystals (UCNs) have been successfully synthesized by a facile solvothermal method. The morphology, crystalline phase, composition, grain size, upconversion luminescence and cell image of the UCNs were investigated. The properties of the NaLuF4-based UCNs were compared with the counterparts of NaYF4-based UCNs. It is found that the NaLuF4-based UCNs are apt to form hexagonal phase structures, while NaYF4-based UCNs of NaYF4:Yb, Er and NaYF4:Gd, Yb, Er are cubic and hexagonal phases respectively. The upconversion emission intensities of the NaLuF4-based UCNs are higher than that of NaYF4-based UCNs, and Gd3+ presented UCNs are higher than that of Gd3+ absented UCNs. The bioimaging application of NaLuF4:Gd, Yb, Er shows that bright upconversion luminescence can be observed when UCNs-labeled HeLa cells are excited with 980 nm light.

Synthesis of a novel core-shell nanocomposite Ag@SiO2@Lu2O3:Gd/Yb/Er for large enhancing upconversion luminescence and bioimaging.

Upconversion nanocrystals have many advantages over other fluorescent materials. However, their upconversion luminescence intensities are not desirable, limiting their applications for highly sensitive detection. Therefore, it is really important to enhance upconversion luminescent intensities of upconversion nanocrystals. In the present study, a novel Ag core and upconversion nanocrystal shell based nanocomposite Ag@SiO2@Lu2O3:Gd/Yb/Er for metal-enhanced upconversion luminescence was fabricated successfully, and its morphology, crystalline phase, composition, optical property, and cell imaging application were investigated. It was found that a maximum upconversion luminescence enhancement of 30-fold was obtained in comparison with the control without a silver core, and the nanocomposite exhibited bright upconversion luminescence when it was used for imaging with HeLa cells. This enhancement potentially increases the overall upconversion nanocrystal detectability, endowing the nanocomposite with a potential capability for highly sensitive biological, medical, and optical detection.

Synthesis of NaLuF4-based nanocrystals and large enhancement of upconversion luminescence of NaLuF4:Gd, Yb, Er by coating an active shell for bioimaging.

A series of NaLuF4-based hexagonal phase upconversion nanocrystals (UCNs) were synthesized by a facile solvothermal method and the properties of the UCNs were investigated. The results show that the as-prepared nanocrystals exhibit pure hexagonal lattice structures, uniform morphologies, high monodispersities and excellent upconversion luminescence. The upconversion luminescence (UCL) intensities of the UCNs can be enhanced by coating with a shell of NaLuF4. More interestingly, the UCL intensities of active-shell coated nanocrystals (NaLuF4:Gd, Yb, Er@NaLuF4:Yb, Ho and NaLuF4:Gd, Yb, Er@NaLuF4:Yb) are remarkably higher than that of inert-shell coated nanocrystals (NaLuF4:Gd, Yb, Er@NaLuF4), and NaLuF4:Gd, Yb, Er@NaLuF4:Yb, Ho is higher than NaLuF4:Gd, Yb, Er@NaLuF4:Yb. The mechanisms of upconversion luminescence enhancement are discussed in detail. The bioimaging application of the nanocrystals showed that bright upconversion luminescence was observed when UCNs-labeled HeLa cells were excited with 980 nm light. This study presents a facile method for the synthesis of NaLuF4-based upconversion nanocrystals with intense luminescence that can be used as potential fluorescent probes for sensitive bioimaging, and the suggested mechanism could provide new insights into fabrication of upconversion materials with high upconversion fluorescence.

Enhancing upconversion luminescence of NaYF4:Yb/Er nanocrystals by Mo(3+) doping and their application in bioimaging.

Enhancement of upconversion luminescence is imperative for the applications of upconversion nanocrystals (UCNs). In this work, we investigated the upconversion luminescence enhancement of NaYF4:Yb/Er by Mo(3+) ion doping. It was found that the upconversion luminescence intensities of the green and red emissions of UCNs co-doped with 10 mol% Mo(3+) ions were enhanced by 6 and 8 times, respectively. This enhancement offers a potential increase in the overall detectability of upconversion nanocrystals. HeLa cell imaging using NaYF4:Yb/Er/Mo as luminescent probes showed bright upconversion fluorescence. Moreover, the Mo(3+) doping endowed the UCNs with excellent paramagnetic behavior. It is expected that the as-prepared UCNs with a high upconversion luminescence and excellent paramagnetic properties could be promising bi-functional nanoprobes for sensitive multi-modal bioimaging and other optical applications.

Synthesis of fluorescent and magnetic bi-functional NaLuF4-based upconversion nanocrystals.

Fluorescent and magnetic bi-functional NaLuF4-based upconversion nanocrystals have been developed by a facile thermal decomposition method. The influences of Mn2+ and Gd3+ doping on the upconversion luminescent and magnetic properties of the nanocrystals were investigated. The results show that Mn2+ doping can promote the transition of green to red and increase the red emission significantly. When the Mn2+ and Gd3+ are co-doped in the nanocrystals, it has a synergistic effect which can further improve the transition and red emission. Moreover, the nanocrystals co-doped with Mn2+ and Gd3+ exhibit excellent superparamagnetic properties. These results suggest that the developed nanocrystals, which have strong pure red upconversion emission and superparamagnetic properties, can serve as a potential upconversion luminescence and magnetic resonance probe for dual-modality bioimaging. This work presents a facile and effective method for modulating the transition of short-wavelength emission to red emission of upconversion nanocrystals, leading the naocrystals exhibiting excellent upconversion luminescence and magnetic properties.

ZnO nanoparticles co-doped with Fe3+ and Eu3+ ions for solar assisted photocatalysis.

In this study, ZnO nanoparticles co-doped with Fe3+ and Eu3+ were prepared by a facile co-precipitation method. The structure and morphology of the as-prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and diffuse reflectance absorption spectra, respectively. The photocatalytic activities of the prepared catalysts were evaluated by photocatalytic degradation of methyl orange in aqueous solution with solar light irradiation. The co-doped Fe3+ and Eu3+ showed a synergistic effect, which significantly increased the photocatalytic activity of ZnO. The influences of calcination time, photocatalytic reaction temperature and catalyst loading on the photocatalytic activity of the catalyst were also investigated. It was found that there were an optimum photocatalytic reaction temperature and an optimum catalyst loading for high photocatalytic efficiency, and the photocatalytic efficiency decreased with increase in calcination time. The results of this study demonstrate that the as-prepared product of Eu3+/Fe3+/ZnO is a promising photocatalyst for solar assisted degradation of organic pollutions.

Synthesis of NaYF4, NaLuF4 and NaGdF4-based upconversion nanocrystals with hydro (solvo) thermal methods.

Serials of NaYF4, NaLuF4 and NaGdF4-based nanocrystals have been synthesized successfully by solvothermal and hydrothermal, respectively. The properties of the products were characterized and compared. The nanocrystals prepared by hydrothermal method exhibited uniform hexagonal phase and large size, while the nanocrystals prepared by solvothermal method displayed high upconversion luminescence (UCL) and small size. The UCL intensities of the nanocrystals prepared by solvothermal method were higher than that of nanocrystals from hydrothermal method. Whether using solvothermal or hydrothermal method, the UCL intensities of the nanocrystals were in the sequence (from strong to weak) of NaLuF4:Gd/Yb/Tm, NaLuF4:Yb/Tm, NaGdF4:Yb/Tm, NaYF4:Gd/Yb/Tm and NaYF4:Yb/Tm, respectively. This is the first time to systematically compare three kinds of host-based nanocrystals, which are prepared by two different approaches with various lanthanide ions doped. This work could provide new insight into fabrication of upconversion nanocrystals with intense UCL and controllable morphology and size via using suitable doping ions, host materials and efficient approaches.