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"Zheng, Mengmeng"
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A Review: The Bioactivities and Pharmacological Applications of Polygonatum sibiricum polysaccharides
2018
Traditional Chinese Medicine (TCM) has been widely used in China and is regarded as the most important therapeutic. Polygonatum sibiricum (PS), a natural plant used in traditional Chinese medicine, has various functions associated with a number of its components. There are many compositions in PS including polysaccharides, steroids, anthraquinone, alkaloids, cardiac glycosides, lignin, vitamins, various acids, and so on. Of these, polysaccharides play a significant role in PS-based therapeutics. This article summarizes Polygonatum sibiricum polysaccharides (PSP) have many pharmacological applications and biological activities, such as their antioxidant activity, anti-aging activity, an anti-fatigue effect, immunity enhancement effect, antibacterial effect, anti-inflammatory effect, hypolipidemic and antiatherosclerotic effects, anti-osteoporosis effect, liver protection, treatment of diabetes mellitus (DM), anti-cancer effect, and may help prevent Alzheimer’s disease, and so on. This review summarized the extraction method, purification method, compositions, pharmacological applications, biological activities, biosynthesis, and prospects of PSP, providing a basis for further study of PS and PSP.
Journal Article
K27-linked ubiquitination of BRAF by ITCH engages cytokine response to maintain MEK-ERK signaling
by
Kim, Minjung
,
Smalley, Keiran S. M.
,
Jiang, Shulong
in
13/106
,
13/109
,
14-3-3 Proteins - metabolism
2019
BRAF plays an indispensable role in activating the MEK/ERK pathway to drive tumorigenesis. Receptor tyrosine kinase and RAS-mediated BRAF activation have been extensively characterized, however, it remains undefined how BRAF function is fine-tuned by stimuli other than growth factors. Here, we report that in response to proinflammatory cytokines, BRAF is subjected to lysine 27-linked poly-ubiquitination in melanoma cells by the ITCH ubiquitin E3 ligase. Lysine 27-linked ubiquitination of BRAF recruits PP2A to antagonize the S365 phosphorylation and disrupts the inhibitory interaction with 14–3–3, leading to sustained BRAF activation and subsequent elevation of the MEK/ERK signaling. Physiologically, proinflammatory cytokines activate ITCH to maintain BRAF activity and to promote proliferation and invasion of melanoma cells, whereas the ubiquitination-deficient BRAF mutant displays compromised kinase activity and reduced tumorigenicity. Collectively, our study reveals a pivotal role for ITCH-mediated BRAF ubiquitination in coordinating the signals between cytokines and the MAPK pathway activation in melanoma cells.
BRAF drives MEK/ERK activation to facilitate tumorigenesis. Here, the authors show that in response to pro-inflammatory cytokines, ITCH mediates a non-proteolytic ubiquitination and activation of BRAF, which in turn sustains MEK/ERK signaling to facilitate melanoma cell growth.
Journal Article
Worsening hearing was associated with higher β-amyloid and tau burden in age-related hearing loss
2022
Age-related hearing loss (ARHL) represents the frequently occurring disability that affects the elderly worldwide. The recent evidence has calculated ARHL to be most potential risk factor to predict dementia. β-amyloid plaques and tau accumulation in brain are hallmarks pathologic feature of Alzheimer’s disease (AD), which is a leading cause resulting in dementia. However, the potential mechanistic associations between ARHL and dementia remains unknown. We performed the present cross-sectional cohort study by enrolling 72 patients from research on hearing as well as the pathologic hallmarks of AD in brain. The exposure of hearing was measured by either word recognition score or mean pure-tone of the superior ear. The brain β-amyloid and tau standardized uptake value ratio (SUVR) were measured by positron emission tomography (PET). The covariates included gender, age, cardiovascular disease, education and hearing aid use. To analyze the association between hearing and β-amyloid/tau, linear regression was used and adjusted for potentially confounding covariates. Our data showed that the mean age was 67.1 ± 2.9 years. After adjusted for all the covariates, SUVR of β-amyloid showed an increase of 0.028 [95% confidence interval (CI) 0.004–0.061;
P
= 0.026], while that of tau exhibited an increase of 0.026 (95% CI 0.003–0.056;
P
= 0.033) per mean pure-tone increase by 10 dB (worsening). Likewise, per mean word-recognition score increase by 10%, the SUVR of β-amyloid showed an increase of 0.060 (95% CI 0.008–0.113;
P
= 0.023), while that of tau exhibited an increase of 0.059 (95% CI 0.009–0.111;
P
= 0.031). Taken together, our data demonstrates that hearing worsening was related to the increased burdens of β-amyloid as well as tau detected by PET, which were the AD pathological markers.
Journal Article
Ginsenosides: A Potential Neuroprotective Agent
2018
Ginseng is a traditional Chinese medicine with a wide range of pharmacological activities. Ginsenosides are the major constituents of ginseng. Ginsenosides have the unique biological activity and medicinal value, such as antitumor, anti-inflammatory, antioxidation, and inhibition of cell apoptosis. With the increase of stress in life, the incidence of nervous system diseases is also increasing. Neurological diseases pose a huge burden on people’s life and health. In recent years, some studies have shown that ginsenosides have a certain role in the prevention and treatment of neurological diseases. However, the research is still in its infancy, and the relevant mechanisms are complex. In the paper, we review the effects and mechanisms of ginsenosides on epilepsy, depression, cerebral ischemia reperfusion injury, Alzheimer’s disease, and Parkinson’s disease. We hope to provide a theoretical basis for the treatment of nervous system diseases by ginsenosides.
Journal Article
Facile Synthesis of P-Doped ZnIn2S4 with Enhanced Visible-Light-Driven Photocatalytic Hydrogen Production
2023
ZnIn2S4 (ZIS) is widely used in the field of photocatalytic hydrogen production due to its unique photoelectric properties. Nonetheless, the photocatalytic performance of ZIS usually faces problems of poor conductivity and rapid recombination of charge carriers. Heteroatom doping is often regarded as one of the effective strategies for improving the catalytic activity of photocatalysts. Herein, phosphorus (P)-doped ZIS was prepared by hydrothermal method, whose photocatalytic hydrogen production performance and energy band structure were fully studied. The band gap of P-doped ZIS is about 2.51 eV, which is slightly smaller than that of pure ZIS. Moreover, due to the upward shift of its energy band, the reduction ability of P-doped ZIS is enhanced, and P-doped ZIS also exhibits stronger catalytic activity than pure ZIS. The optimized P-doped ZIS exhibits a hydrogen production rate of 1566.6 μmol g−1 h−1, which is 3.8 times that of the pristine ZIS (411.1 μmol g−1 h−1). This work provides a broad platform for the design and synthesis of phosphorus-doped sulfide-based photocatalysts for hydrogen evolution.
Journal Article
The learning curve for modified hand-assisted retroperitoneoscopic living donor nephrectomy
2024
Background
We aimed to introduce our modified hand-assisted retroperitoneoscopic living donor nephrectomy (HARPLDN) technique and define the learning curve.
Methods
One hundred thirty-eight kidney donors who underwent modified HARPLDN by the same surgeon between May 2015 and March 2022 were included. A cumulative sum (CUSUM) learning curve analysis was performed with the total operation time as the study outcome.
Results
In total, the mean operative time was 138.2 ± 32.1 min. The median warm ischemic time (WIT) and estimated blood loss were 90 s and 50 ml, respectively. The learning curve for the total operative time was best modeled as a second-order polynomial with the following equation: CUSUM
OT
(min) = (–0.09 case number
2
) + (12.88 case number) – 67.77 (R
2
= 0.7875;
p
<0.05). The CUSUM learning curve included the following three unique phases: phase 1 (the initial 41 cases), representing the initial learning curve; phase 2 (the middle 43 cases), representing expert competence; and phase 3 (the final 54 cases), representing mastery. The overall 6-month graft survival rate was 99.3%, with 94.9% immediate onset of graft function without delayed graft function and 0.7% ureteral complications.
Conclusions
Our modified method is safe and effective for living donor nephrectomy and has the advantages of a shorter operating time and optimized WIT. The surgeon can become familiar with the modified HARPLDN after 41 cases and effectively perform the next 97 cases.
Journal Article
Fbxo45 facilitates the malignant progression of breast cancer by targeting Bim for ubiquitination and degradation
2024
Background
Breast cancer is one of the common malignancies in women. Evidence has demonstrated that FBXO45 plays a pivotal role in oncogenesis and progression. However, the role of FBXO45 in breast tumorigenesis remains elusive. Exploration of the regulatory mechanisms of FBXO45 in breast cancer development is pivotal for potential therapeutic interventions in patients with breast cancer.
Methods
Hence, we used numerous approaches to explore the functions of FBXO45 and its underlaying mechanisms in breast cancer pathogenesis, including CCK-8 assay, EdU assay, colony formation analysis, apoptosis assay, RT-PCR, Western blotting, immunoprecipitation, ubiquitination assay, and cycloheximide chase assay.
Results
We found that downregulation of FBXO45 inhibited cell proliferation, while upregulation of FBXO45 elevated cell proliferation in breast cancer. Silencing of FBXO45 induced cell apoptosis, whereas overexpression of FBXO45 inhibited cell apoptosis in breast cancer. Moreover, FBXO45 interacted with BIM and regulated its ubiquitination and degradation. Furthermore, knockdown of FBXO45 inhibited cell proliferation via regulation of BIM pathway. Notably, overexpression of FBXO45 facilitated tumor growth in mice. Strikingly, FBXO45 expression was associated with poor survival of breast cancer patients.
Conclusion
Our study could provide the rational for targeting FBXO45 to obtain benefit for breast cancer patients. Altogether, modulating FBXO45/Bim axis could be a promising strategy for breast cancer therapy.
Journal Article
Dynamic Optimization of Emergency Infrastructure Layouts Based on Population Influx: A Macao Case Study
2025
This study investigates the spatiotemporal optimization of small-scale emergency infrastructure in high-density urban environments, using nucleic acid testing sites in Macao as a case study. The objective is to enhance emergency responsiveness during future public health crises by aligning infrastructure deployment with dynamic patterns of population influx. A behaviorally informed spatial decision-making framework is developed through the integration of kernel density estimation, point-of-interest (POI) distribution, and origin–destination (OD) path simulation based on an Ant Colony Optimization (ACO) algorithm. The results reveal pronounced temporal fluctuations in testing demand—most notably with crowd peaks occurring around 12:00 and 18:00—and highlight spatial mismatches between existing facility locations and key residential or functional clusters. The proposed approach illustrates the feasibility of coupling infrastructure layout with real-time mobility behavior and offers transferable insights for emergency planning in compact urban settings.
Journal Article
Unique solvability of weakly homogeneous generalized variational inequalities
2021
An interesting observation is that most pairs of weakly homogeneous mappings do not possess strongly monotonic property, which is one of the key conditions to ensure the unique solvability of the generalized variational inequality. This paper focuses on studying the uniqueness and solvability of the generalized variational inequality with a pair of weakly homogeneous mappings. By using a weaker condition than the strong monotonicity and some additional conditions, we achieve several results on the unique solvability to the underlying problem, which are exported by making use of the exceptional family of elements. As an adjunct, we also obtain the nonemptiness and compactness of the solution sets to the weakly homogeneous generalized variational inequality under some appropriate conditions. The conclusions presented in this paper are new or supplements to the existing ones even when the problem comes down to its important subclasses studied in recent years.
Journal Article
Hyperspectral Image Classification Promotion Using Dynamic Convolution Based on Structural Re-Parameterization
by
Li, Xu
,
Xu, Yaoyang
,
Zhang, Lei
in
Accuracy
,
Artificial intelligence
,
Artificial neural networks
2023
In a hyperspectral image classification (HSIC) task, manually labeling samples requires a lot of manpower and material resources. Therefore, it is of great significance to use small samples to achieve the HSIC task. Recently, convolutional neural networks (CNNs) have shown remarkable performance in HSIC, but they still have some areas for improvement. (1) Convolutional kernel weights are determined through initialization and cannot be adaptively adjusted based on the input data. Therefore, it is difficult to adaptively learn the structural features of the input data. (2) The convolutional kernel size is single per layer, which leads to the loss of local information for a large convolutional kernel or global information for a small convolutional kernel. In order to solve the above problems, we propose a plug-and-play method called dynamic convolution based on structural re-parameterization (DCSRP). The contributions of this method are as follows. Firstly, compared with traditional convolution, dynamic convolution is a non-linear function, so it has more representation power. In addition, it can adaptively capture the contextual information of input data. Secondly, the large convolutional kernel and the small convolutional kernel are integrated into a new large convolutional kernel. The large convolutional kernel shares the advantages of the two convolution kernels, which can capture global information and local information at the same time. The results in three publicly available HSIC datasets show the effectiveness of the DCSRP.
Journal Article