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Zhijun Yang

Publications and source records attributed to Zhijun Yang.

10 recordsLinked to original sources
PubMed2026

NR3C1 Modulates Wnt Signalling to Influence the Invasiveness and Immune Features of Nonfunctioning Invasive Pituitary Adenomas.

Pituitary adenomas (PAs) are common intracranial tumours, and invasiveness in nonfunctioning invasive pituitary adenomas (NIPAs) predicts poor prognosis. The molecular mechanisms driving this phenotype remain unclear. This study explored the role of nuclear receptor subfamily 3 group C member 1 (NR3C1) in NIPA invasiveness and its regulation of Wnt signalling. mRNA expression profiles of 32 PA samples were generated by RNA-seq, and proteomic data from 19 samples were obtained by mass spectrometry. Immune-related differentially expressed genes (DEGs) were retrieved from GeneCards. Weighted gene coexpression network analysis identified modules and hub genes linked to invasiveness, while machine learning methods (support vector machine, LASSO, random forest) prioritised key genes. Gene set enrichment analysis (GSEA) assessed pathways associated with candidate gene expression. NR3C1 expression and function were validated by immunohistochemistry, Western blotting and invasion assays. Integration of transcriptomic, proteomic and immune-related datasets yielded 11 overlapping genes, with NR3C1 emerging as the top candidate. NR3C1 was significantly upregulated in NIPAs and demonstrated good discriminatory power by ROC analysis. GSEA associated high NR3C1 expression with Wnt pathway activation. Functional experiments confirmed that NR3C1 overexpression enhances the invasive capacity of PA cells. NR3C1 promotes the invasive phenotype of NIPAs by activating Wnt signalling. These findings suggest NR3C1 as a potential biomarker and therapeutic target for invasive pituitary adenomas.

Humans↗
PubMed2006

Catalytic detoxification of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in fly ash.

An efficient catalytic detoxification method for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in fly ash produced by municipal waste incinerator has been studied using palladium on carbon (Pd/C) catalyst. As one of the trace components in fly ash, the detoxification of PCDD/Fs is very difficult because of the interferences of other persistent components with higher concentrations. However, the detoxification reaction of PCDD/Fs shows higher activity in water/isopropanol solution using commercial Pd/C catalyst at 40 degrees C under normal pressure. The results indicated that the catalytic degradation of PCDFs has been found to be easier than that of PCDDs. Moreover, the dechlorination ratios were higher for octa- and hepta-chlorinated congeners than those for tetra- and penta-chlorinated ones. The detoxification process worked well in water. The dechlorination efficiencies of almost all of the PCDD/Fs congeners can reach over 99% within a shorter reaction time.

2-Propanol↗
PubMed2006

A neuromorphic depth-from-motion vision model with STDP adaptation.

We propose a simplified depth-from-motion vision model based on leaky integrate-and-fire (LIF) neurons for edge detection and two-dimensional depth recovery. In the model, every LIF neuron is able to detect the irradiance edges passing through its receptive field in an optical flow field, and respond to the detection by firing a spike when the neuron's firing criterion is satisfied. If a neuron fires a spike, the time-of-travel of the spike-associated edge is transferred as the prediction information to the next synapse-linked neuron to determine its state. Correlations between input spikes and their timing thus encode depth in the visual field. The adaptation of synapses mediated by spike-timing-dependent plasticity is used to improve the algorithm's robustness against inaccuracy caused by spurious edge propagation. The algorithm is characterized on both artificial and real image sequences. The implementation of the algorithm in analog very large scale integrated (aVLSI) circuitry is also discussed.

Animals↗
PubMed2006

An adaptive visual neuronal model implementing competitive, temporally asymmetric Hebbian learning.

A novel depth-from-motion vision model based on leaky integrate-and-fire (I&F) neurons incorporates the implications of recent neurophysiological findings into an algorithm for object discovery and depth analysis. Pulse-coupled I&F neurons capture the edges in an optical flow field and the associated time of travel of those edges is encoded as the neuron parameters, mainly the time constant of the membrane potential and synaptic weight. Correlations between spikes and their timing thus code depth in the visual field. Neurons have multiple output synapses connecting to neighbouring neurons with an initial Gaussian weight distribution. A temporally asymmetric learning rule is used to adapt the synaptic weights online, during which competitive behaviour emerges between the different input synapses of a neuron. It is shown that the competition mechanism can further improve the model performance. After training, the weights of synapses sourced from a neuron do not display a Gaussian distribution, having adapted to encode features of the scenes to which they have been exposed.

Algorithms↗
PubMed2006

Inhibitory effects of magnolol on distal colon of guinea pig in vitro.

The influence of plant product magnolol (0-100 microM) on the contractile activity of isolated colonic muscle strips in guinea pig and related mechanism were investigated. Magnolol did not affect the base tone of colon muscle strips, but it dose-dependently inhibited 40 mM KCl-, 1 microM carbachol (CCh)- and 10 microM serotonin (5-HT)-induced contractions at concentrations higher than 10 microM. And also, magnolol inhibited the 5-HT- or CCh-induced muscle contraction in calcium-free buffer. Furthermore, magnolol inhibited the KCl-induced contraction under the condition of procaine. In addition, inhibition rate of nifedipine plus magnolol on muscle strips was lower than that of nifedipine alone. Moreover, magnolol dose-dependently decreased the velocity of pellet propulsion in the concentration range of 0.1-10 microM, and totally inhibited pellet propulsion at the concentration higher than 30 microM. Thus, it can be concluded that magnolol may 1) block receptor-operated cation channels and the voltage dependent Ca2+ channel, and 2) inhibit calcium release from the sarcolemmal membrane (SR) through blocking InsP3-sensitive and ryanodine-sensitive pathways. This explains, at least partially, that Cortex magnoliae officinalis exerts therapeutic effects on gastrointestinal disease through relaxation of GI tract smooth muscles.

Anesthetics, Local↗
PubMed2006

Control release effects of binders used in pills of traditional Chinese medicine herbs.

This research investigated the effects of control release of binders that are used in the pills of Chinese herbal medicine, namely, as processed honey, starch paste, beeswax, or mixtures thereof. Aspirin and baicalin were used as the active pharmaceutical ingredients (API). The processed honey was heated to 110 degrees C, 120 degrees C, or 130 degrees C. In these pills, the binders were the only excipients. The pills were prepared by the stir method using a mixer at 80 degrees C without pressure. The differential thermal analysis (DTA) showed that the melting points of aspirin and baicalin were changed by the binders. The Fourier Transform infrared spectra (FT-IR) of aspirin and baicalin suggest that there are different non-covalent molecular interactions between the API and the binders, such as C-H-pi and hydrogen bond interaction. The dissolution profiles indicate that changing the ratio of the binders altered the patterns of dissolution of the API; thus, this ration may be used to control the release of API from the pills.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

A probabilistic neural network as the predictive classifier of out-of-hospital defibrillation outcomes.

INTRODUCTION: Although modern defibrillators are nearly always successful in terminating ventricular fibrillation (VF), multiple defibrillation attempts are usually required to achieve return of spontaneous circulation (ROSC). This is potentially deleterious as cardiopulmonary resuscitation (CPR) must be discontinued during each defibrillation attempt which causes deterioration in the heart muscle and reduces the chance of ROSC from later defibrillation attempts. In this work defibrillation outcomes are predicted prior to electrical shocks using a neural network model to analyse VF time series in an attempt to avoid defibrillation attempts that do not result in ROSC. METHODS: The 198 pre-shock VF ECG episodes from 83 cardiac arrest patients with defibrillation conversions to different outcomes were selected from the Oslo ambulance service database. A probabilistic neural network model was designed for training and testing with a cross validation method being used for the better generalisation performance. RESULTS: We achieved an accuracy of 75% in overall prediction with a sensitivity of 84% and a specificity of 65% using VF ECG time series of an order of 1 s in length. CONCLUSION: Pre-shock VF ECG time series can be classified according to the defibrillation conversion to a return of spontaneous circulation (ROSC) or No-ROSC.

Area Under Curve↗
PubMed2004

[Determination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in newsprints and copy papers by HRGC/HRMS].

The concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in newsprints and copy papers which included blank and printed paper samples were determined by isotope dilution and high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). All of the paper samples collected at random were extracted with organic solvents and the extracts were cleaned up successively by three different chromatographic columns. The results indicated that the total concentrations of PCDD/ Fs in newsprints were higher than those in copy papers, but the total toxicity equivalent (TEQ) values of newsprint samples were lower than those in copy paper samples. In addition, for both papers, the concentrations of PCDD/Fs in printed papers were higher than the blank papers. Moreover, the patterns of PCDD/Fs in newsprint samples and copy paper samples were different. The total international TEQ values of PCDD/Fs in newsprints and printed newsprints were 0.48 ng/kg and 0.61 ng/kg, respectively. Moreover, the total TEQ values of PCDD/Fs in copy paper and printed copy paper samples were 0.74 ng/kg and 0.79 ng/kg, respectively. The recoveries of 13C labeled 2, 3 ,7, 8-substituted PCDD/Fs spiked before extraction into all paper samples were between 49.82% and 131.34%.

Benzofurans↗
PubMed2003

A generalized locomotion CPG architecture based on oscillatory building blocks.

Neural oscillation is one of the most extensively investigated topics of artificial neural networks. Scientific approaches to the functionalities of both natural and artificial intelligences are strongly related to mechanisms underlying oscillatory activities. This paper concerns itself with the assumption of the existence of central pattern generators (CPGs), which are the plausible neural architectures with oscillatory capabilities, and presents a discrete and generalized approach to the functionality of locomotor CPGs of legged animals. Based on scheduling by multiple edge reversal (SMER), a primitive and deterministic distributed algorithm, it is shown how oscillatory building block (OBB) modules can be created and, hence, how OBB-based networks can be formulated as asymmetric Hopfield-like neural networks for the generation of complex coordinated rhythmic patterns observed among pairs of biological motor neurons working during different gait patterns. It is also shown that the resulting Hopfield-like network possesses the property of reproducing the whole spectrum of different gaits intrinsic to the target locomotor CPGs. Although the new approach is not restricted to the understanding of the neurolocomotor system of any particular animal, hexapodal and quadrupedal gait patterns are chosen as illustrations given the wide interest expressed by the ongoing research in the area.

Algorithms↗