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1.
ACS Nano ; 11(5): 4407-4418, 2017 05 23.
Article in English | MEDLINE | ID: mdl-28297600

ABSTRACT

2D transition metal carbides and nitrides known as MXenes are gaining increasing attention. About 20 of them have been synthesized (more predicted) and their applications in fields ranging from energy storage and electromagnetic shielding to medicine are being explored. To facilitate the search for double-transition-metal MXenes, we explore the structure-stability relationship for 8 MXene alloy systems, namely, (V1-xMox)3C2, (Nb1-xMox)3C2, (Ta1-xMox)3C2, (Ti1-xMox)3C2, (Ti1-xNbx)3C2, (Ti1-xTax)3C2, (Ti1-xVx)3C2, and (Nb1-xVx)3C2, with 0 ≤ x ≤ 1, using high-throughput computations. Starting from density-functional theory calculated formation energies, we used the cluster expansion method to build quick-to-compute interactions, enabling us to scan through the formation energies of millions of alloying configurations. For the Mo-rich MXenes, (M11-xMox)3C2 (where M1: Ti, V, Nb, Ta) Mo atoms prefer to occupy the surface layers, and ordering persists to high temperatures, based on our Monte Carlo simulations. When Ti is alloyed with Nb or Ta, in the Ti-rich MXenes, Ti atoms prefer the surface layers (e.g., Ti-C-Nb-C-Ti sequence), and in the Nb- or Ta-rich MXenes, Ti occupies only one surface layer and the other two layers are Nb or Ta (e.g., Ti-C-Nb-C-Nb), exhibiting asymmetric ordering. However, alloying Ti with V results in solid solutions across all compositions. (Nb1-xVx)3C2 phase separates at lower temperatures but forms solid solutions at synthesis temperatures. Postsynthesis annealing at moderate temperatures (800 to 1000 K) increases the ordering for all the compositions. Lastly, by investigating the stability of their precursor MAX phases and surface-terminated MXenes, we discuss the synthesis possibilities of highly ordered MXenes.

2.
Clin Psychopharmacol Neurosci ; 12(3): 222-8, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25598827

ABSTRACT

OBJECTIVE: A randomized double-blind cross-over trial was conducted in patients with persistent auditory hallucinations (AHs) to investigate whether bilateral repetitive transcranial magnetic stimulation (rTMS) at the temporoparietal area or Broca's area is more effective at high- or low-frequencies compared to a sham condition. METHODS: Twenty three patients with persistent AHs who remained stable on the same medication for 2 months were enrolled. They were randomized to one of four conditions: low-frequency (1 Hz)-rTMS to the temporoparietal area (L-TP), high-frequency (20 Hz)-rTMS to the temporoparietal area (H-TP), high-frequency (20 Hz)-rTMS to Broca's area (H-B), or sham. RESULTS: All the four rTMS conditions resulted in significant decrease in the scores under the auditory hallucination rating scale and hallucination change scale over time. However, there were no significant treatment effects or interaction between time and treatment, suggesting no superior effects of the new paradigms over the sham condition. CONCLUSION: Our findings suggest that bilateral rTMS at the temporoparietal area or Broca's area with high- or low-frequency does not produce superior effects in reducing AHs compared to sham stimulation.

3.
Psychopharmacology (Berl) ; 228(2): 217-30, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23468099

ABSTRACT

RATIONALE: Social defeat stress induces physiological and behavioral symptoms, including anxiety, anhedonia, immune deficits, and altered expression of key brain genes. OBJECTIVES: The present study investigated the effects of social defeat stress on the behaviors and expressions of Chat, Grp78, and chop in the brains of adult mice. METHODS: Adult mice were divided into susceptible and unsusceptible groups after 10 days of social defeat stress. In experiment 1, behavioral tests were conducted, and brains were processed for Western blotting at day 27 after stress. In experiment 2, social avoidance tests were conducted, and brains were processed for Western blotting at day 12 after stress. RESULTS: The results indicate decreased and increased locomotion and anxiety behavior in all defeated mice. Decrease in social interaction, increased immobility, and impaired memory performance were only observed in susceptible mice. A decrease in the Chat level at days 12 and 27 was noted in the prefrontal cortex (PFC), amygdala (Amyg), and dorsal hippocampus (HIP) in defeated mice. The expression levels of Grp78 and chop measured on days 12 and 27 were significantly greater in the Amyg of susceptible mice. In the PFC and HIP, defeated mice displayed different patterns in the levels of Grp78 and chop expressions measured on days 12 and 27. CONCLUSIONS: The present study demonstrated that chronic social defeat stress in mice produces stress-related behaviors. Different response patterns were noted for Grp78 and chop expression among the groups in terms of brain regions and time-course effects.


Subject(s)
Choline O-Acetyltransferase/genetics , Heat-Shock Proteins/genetics , Stress, Psychological/physiopathology , Transcription Factor CHOP/genetics , Amygdala/metabolism , Animals , Anxiety/physiopathology , Behavior, Animal , Blotting, Western , Choline O-Acetyltransferase/metabolism , Dominance-Subordination , Endoplasmic Reticulum Chaperone BiP , Heat-Shock Proteins/metabolism , Hippocampus/metabolism , Locomotion , Male , Mice , Mice, Inbred C57BL , Prefrontal Cortex/metabolism , Time Factors , Transcription Factor CHOP/metabolism
4.
Int J Neuropsychopharmacol ; 16(7): 1635-47, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23442729

ABSTRACT

The present study investigated the effects of social defeat stress on the behaviours and expressions of 78-kDa glucose-regulated protein (Grp78), CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) and choline acetyltransferase (Chat) in the brains of adolescent mice. Adolescent male C57BL/6J mice were divided into two groups (susceptible and unsusceptible) after 10 d social defeat stress. In expt 1, behavioural tests were conducted and brains were processed for Western blotting on day 21 after stress. In expt 2, social avoidance tests were conducted and brains were subsequently processed for Western blotting on day 12 after stress. Chronic social defeat stress produced more pronounced depression-like behaviours such as decreased locomotion and social interaction, increased anxiety-like behaviours and immobility, and impaired memory performance in susceptible mice. Moreover, susceptible mice showed greater expression of Grp78 and CHOP in the amygdala (Amyg) on days 12 and 21 compared with the other groups. Susceptible and unsusceptible groups showed significant increases in Grp78 and CHOP expression in the prefrontal cortex (PFC) and hippocampus (Hipp) on day 12 compared with the control group; this persisted until day 21. The levels of Chat measured on days 12 and 21 were significantly lower in the PFC, Amyg and Hipp of all defeated mice compared with controls. The findings of the behavioural tests indicate that chronic social defeat in adolescents produces anxiety-like behaviours, social withdrawal, despair-like behaviours and cognitive impairment. The Grp78, CHOP and Chat results suggest that the selective response of endoplasmic reticulum stress proteins in the Amyg plays an important role in the vulnerability-stress model of depression.


Subject(s)
CCAAT-Enhancer-Binding Proteins/metabolism , Choline O-Acetyltransferase/metabolism , Heat-Shock Proteins/metabolism , Interpersonal Relations , Stress, Psychological , Animals , Brain/metabolism , Brain/pathology , Disease Models, Animal , Endoplasmic Reticulum Chaperone BiP , Male , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , Motor Activity/physiology , Recognition, Psychology , Stress, Psychological/metabolism , Stress, Psychological/pathology , Stress, Psychological/physiopathology , Swimming
5.
Neural Regen Res ; 8(12): 1061-70, 2013 Apr 25.
Article in English | MEDLINE | ID: mdl-25206400

ABSTRACT

Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide (Aß)-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blume on Alzheimer's disease, we established a rat model of Alzheimer's disease by injecting Aß25-35 into bilateral hippocampi. These rats were intragastrically administered 500 or 1 000 mg/kg Gastrodia elata Blume per day for 52 consecutive days. Morris water maze tests showed that Gastrodia elata Blume treatment significantly improved the spatial memory of Alzheimer's disease rats. Congo red staining revealed that Gastrodia elata Blume significantly reduced the number of amyloid deposits in the hippocampus of these rats. Western blot analysis showed that choline acetyltransferase expression in the medial septum and hippocampus was significantly increased by the treatment of Gastrodia elata Blume, while Ellman method showed significant decrease in the activity of acetylcholinesterase in all three regions (prefrontal cortex, medial septum and hippocampus). These findings suggest that long-term administration of Gastrodia elata Blume has therapeutic potential for Alzheimer's disease.

6.
Chinese Journal of Pathology ; (12): 829-832, 2013.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-288197

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the clinical significance of atypical squamous cells of unknown significance (ASCUS) with abnormal DNA ploidy in the early diagnosis of cervical lesions.</p><p><b>METHODS</b>Eight thousand four hundred and forty-eight patients were included in this study and all had DNA quantitative analysis and cervical liquid-based cytology. Among 1041 cases with DNA aneuploidy and/or abnormal cervical liquid-based cytology and additional cervical biopsy, histological review was performed in 247 ASCUS cases with abnormal DNA ploidy.</p><p><b>RESULTS</b>(1) Among 8448 cases, 7877 were normal or benign, 426 were ASCUS, 45 were ASC-H, 55 were LSIL and 22 were HSIL by TBS diagnosis. The presence of 1-2 abnormal DNA ploidy cells was detected in 15.3% (65/426) of ASCUS, 11.1% (5/45) of ASC-H, 9.1% (5/55) of LSIL, and 0 (0/22) of HSIL. The presence of ≥ 3 abnormal DNA ploidy cells was detected in 39.0% (166/426) of ASCUS, 75.6% (34/45) of ASC-H, 76.4% (42/55) of LSIL, and 95.5% (21/22) of HSIL. (2) A total of 67 cases of CIN 2, CIN 3 or cancers were found in 247 patients with ASCUS by colposcopy biopsies, of which 13.9% (5/36) had 1-2 abnormal DNA ploidy cells, 45.5% (56/123) had ≥ 3 abnormal DNA ploidy cells and 6.8% (6/88) had normal DNA polidy. ASCUS with 1-2 abnormal DNA ploidy cells and with ≥ 3 abnormal DNA ploidy cells were compared. The difference was statistically significant (χ(2) = 11.79, P < 0.01). But the difference between ASCUS with 1-2 abnormal DNA ploidy cells and normal DNA ploidy had no statistical significance (P > 0.05).</p><p><b>CONCLUSIONS</b>ASCUS with ≥ 3 abnormal DNA ploidy cells has higher risk for developing CIN 2, CIN 3 or invasive carcinoma. The application of DNA quantitative analysis and cervical liquid-based cytology test can help in guiding clinical follow-up and treatment options in patients with ASCUS.</p>


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Middle Aged , Young Adult , Adenocarcinoma , Diagnosis , Genetics , Pathology , Aneuploidy , Carcinoma in Situ , Diagnosis , Genetics , Pathology , Carcinoma, Squamous Cell , Diagnosis , Genetics , Pathology , Uterine Cervical Dysplasia , Diagnosis , Genetics , Pathology , Colposcopy , DNA, Neoplasm , Genetics , Uterine Cervical Dysplasia , Diagnosis , Genetics , Pathology , Uterine Cervical Neoplasms , Diagnosis , Genetics , Pathology
7.
Int J Mol Sci ; 12(8): 4770-80, 2011.
Article in English | MEDLINE | ID: mdl-21954324

ABSTRACT

Anti-fatigue properties of tartary buckwheat extracts (TBE) was investigated in male Kunming mice. The animals were divided into four groups. The first group, designated as the control group (control), was administered with distilled water by gavage every day for 28 days. The other three groups, designated as TBE treatment groups, were administered with TBE of 60, 120 and 240 mg/kg body weight, respectively, by gavage every day for 28 days. Exhaustive swimming time, blood lactic acid (BLA), blood urea nitrogen (BUN), tissue glycogen, glutathione peroxidase (GPx) and superoxide dismutase (SOD) of mice after swimming were determined. The results showed that tartary buckwheat extracts had anti-fatigue properties, which extended the exhaustive swimming time of mice, effectively inhibiting the increase of BLA, decreasing the level of BUN, increasing the tissue glycogen content and the activities of SOD and GPx of mice. However, further study is needed to elucidate the exact mechanism of the effect of TBE on fatigue.


Subject(s)
Fagopyrum/chemistry , Fatigue/drug therapy , Fatigue/metabolism , Plant Extracts/pharmacology , Animals , Blood Urea Nitrogen , Glutathione/metabolism , Glycogen/metabolism , Lactic Acid/blood , Male , Mice , Models, Animal , Motor Activity/drug effects , Physical Conditioning, Animal , Plant Extracts/administration & dosage , Superoxide Dismutase/metabolism
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 838-41, 2010 Mar.
Article in Chinese | MEDLINE | ID: mdl-20496722

ABSTRACT

The rapid development of astronomical observation has led to many large sky surveys such as SDSS (Sloan digital sky survey) and LAMOST (large sky area multi-object spectroscopic telescope). Since these surveys have produced very large numbers of spectra, automated spectral analysis becomes desirable and necessary. The present paper studies the spectral classification method based on Bayes decision theory, which divides spectra into three types: star, galaxy and quasar. Firstly, principal component analysis (PCA) is used in feature extraction, and spectra are projected into the 3D PCA feature space; secondly, the class conditional probability density functions are estimated using the non-parametric density estimation technique, Parzen window approach; finally, the minimum error Bayes decision rule is used for classification. In Parzen window approach, the kernel width affects the density estimation, and then affects the classification effect. Extensive experiments have been performed to analyze the relationship between the kernel widths and the correct classification rates. The authors found that the correct rate increases with the kernel width being close to some threshold, while it decreases with the kernel width being less than this threshold.

9.
Chinese Journal of Pathology ; (12): 156-160, 2010.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-273412

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the expression of HER2/neu, Ki-67 and TK1 protein in meningiomas in correlation with tumor grades and recurrence.</p><p><b>METHODS</b>Twenty cases of each of the following types of meningiomas were selected for the study, namely: the benign non-recurrent, recurrent benign, atypical and malignant, according to the World Health Organization (WHO) histological classification of nervous system, 2007. Immunohistochemistry study for HER2/neu, Ki-67 and TK1 protein was performed. HER2/neu gene amplification was detected using FISH. Cases with HER2 protein overexpression were studied by immunohistochemistry staining. The results of the biomarker assays were also used to study the correlationship with the tumor grades and tumor recurrency.</p><p><b>RESULTS</b>Immunohistochemistry showed that the positive rates of HER2 expression in non-recurrence benign group, recurrence benign group, atypical group and malignant group were 3 cases (15%), 6 cases (30%), 7 cases (35%), and 10 cases (50%), respectively (P < 0.05). A higher tumor grade was correlated with a higher rate of HER2/neu expression. The Ki-67 and TK1 labeling index (LI) in non-recurrence group were lower than those in the atypical or malignant group (P < 0.05), whereas the atypical group had lower LI than that of the malignant group (P < 0.05). Higher levels of LI of Ki-67 and TK1 were correlated with higher tumor grades and recurrence of the benign meningiomas (P < 0.05). Expression of HER2 was positively correlated with Ki-67 and TK1 (r = 0.445, P < 0.01; r = 0.501, P < 0.01, respectively), and there was a positive correlation between Ki-67 and TK1 (r = 0.450, P < 0.01) as well. HER2/neu gene copy amplification in 7 of 26 cases (26.9%) of HER2 immunopositive meningiomas. The rates of HER2/neu gene amplification were 0 in tumors with 1+ immunopositivity, 4/6 in tumor with 2+ immunopositivity and 3/4 in tumor with 3+ immunopositivity. HER2/neu gene amplification in 3+ and 2+ immunopositive cases had no statistical significance (P > 0.05). Aneuploidy of chromosome 17 existed in 9 of 26 of HER2 immunopositive meningiomas (34.6%). However, the rates of chromosome 17 aneuploidy had no significant difference among tumors with variable HER2/neu imumopositivity (P > 0.05).</p><p><b>CONCLUSIONS</b>High levels of HER2 and Ki-67 or TK1 expression correlate with the increase of tumor grades and tumor recurrence. HER2/neu gene amplification is seen in a subset of meningiomas with the protein expression (26.9%). A combination of biomarker study including HER2/neu, Ki-67 and TK1 may be useful in predicting the biological behavior of meningiomas.</p>


Subject(s)
Female , Humans , Male , Middle Aged , Aneuploidy , Chromosomes, Human, Pair 17 , Gene Amplification , Immunohistochemistry , In Situ Hybridization, Fluorescence , Ki-67 Antigen , Metabolism , Meningeal Neoplasms , Genetics , Metabolism , Pathology , Meningioma , Genetics , Metabolism , Pathology , Neoplasm Recurrence, Local , Receptor, ErbB-2 , Genetics , Metabolism , Thymidine Kinase , Metabolism
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