1.Studies on Shedding Virus and the Formation of Aerosol of H_9N_2 Subtype AIV
Yong-Zhi CAO ; Wei-Ming MA ; Xiao-Xia LI ; Tong-Jie CHAI ; Hai-Yan ZHANG ;
Microbiology 2008;0(10):-
In order to study the regularity of shedding virus from infected SPF chickens and the formation of aerosol of H9N2 subtype AIV, SPF chickens were bred in a positive and negative pressure isolator. Aerosol samples were collected by AGI-30 (All Glass Impinger-30) extractor, and simultaneously trachea and cloaca samples were collected by tracheal swabs and cloacal swabs in different periods after challenged with vi- ruses. The above-mentioned samples were detected by HI, Dot-ELISA and RT-PCR methods. The results in- dicated that aerosols were isolated from the 4 days to the 43 days after inoculation. It was proved that H9N2 subtype AIV could copy themselves in respiratory passage and cloaca, and then could formation of aerosols. AIV H9N2 subtype could be isolated from cloacal and tracheal swabs 3 days after inoculation and lasted for 45 days, viruses were detected from all infected SPF chickens on 7 days.
2.Research on and design of visual prosthesis based on visual information processing.
Sheng LI ; Jie HU ; Xinyu CHAI ; Qiushi REN ; Yinghong PENG
Journal of Biomedical Engineering 2012;29(4):754-759
Induced by a variety of retinopathy, visual loss has become the most serious form of disability, which influences the quality of human life. With the rapid development and crossing among the information science, microelectronics, material science and biomedical disciplines, the visual prosthesis makes reparation possible for the visual blindness caused by retinitis pigmentosa, age-related macular degeneration, and other eye, retina, optic nerve and visual cortex lesions. With technology innovation, the prosthesis design, manufacturing and surgical technique are no longer the biggest obstacles to the future development of the visual prosthesis, but how to construct effective transmission of information between the brain and the prosthesis. However, due to the complex structure of the human visual system, the visual prosthesis manufacturing and visual information signal mapping are facing some difficulties. Thus, we can only study the representation strategy of image information and micro-electrode array stimulation basing on limited pixels of simulated prosthesis visual information. By studying the visual information processing of the visual prosthesis, we propose a visual prosthesis design which is based on biological, mechanical, and electronic integration.
Blindness
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rehabilitation
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Electric Stimulation
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Electrodes, Implanted
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Humans
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Prosthesis Design
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Visual Perception
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Visual Prosthesis
3.Mechanism related to docosahexaenoic acid induced large conductance calcium-activated potassium channel currents increase in coronary smooth muscle cells.
Ru-xing WANG ; Ku-lin LI ; Chang-ying ZHANG ; Jie ZHENG ; Su-xia GUO ; Ying WU ; Xiao-rong LI ; Qiang CHAI ; Tong LU ; Hon-chi LEE
Chinese Journal of Cardiology 2011;39(4):348-352
OBJECTIVETo investigate the mechanism of enhanced large conductance calcium-activated potassium channel currents (BK) in coronary smooth muscle cells (SMCs) by docosahexaenoic acid (DHA).
METHODSCoronary SMCs were isolated by enzyme digestion. Potassium channels in coronary SMCs were identified by applications of different potassium blockers. Effects of DHA and its metabolite 16, 17-epoxydocosapentaenoic acid (16, 17-EDP) on BK channels in the absence and presence of cytochrome P450 epoxygenase inhibitor SKF525A were studied by patch clamp in whole-cell configuration.
RESULTSBK channels were widely distributed in SMCs, and BK currents in normal SMCs accounted for (64.2 ± 2.7)% of total potassium currents (n = 20). DHA could activate BK channels, and its 50% effective concentration (EC(50)) was (0.23 ± 0.03) µmol/L, however, the effect of DHA on BK channels was abolished after SMCs were incubated with cytochrome P450 epoxygenase inhibitor SKF525A. 16, 17-EDP, a metabolite of DHA, could reproduce the effects of DHA on BK channels, and its EC(50) was (19.7 ± 2.8) nmol/L.
CONCLUSIONDHA and metabolites can activate BK channels and dilate coronary arteries through activating cytochrome P450 epoxygenase pathway.
Animals ; Coronary Vessels ; cytology ; drug effects ; metabolism ; Cytochrome P-450 Enzyme Inhibitors ; Docosahexaenoic Acids ; pharmacology ; Fatty Acids, Unsaturated ; pharmacology ; Large-Conductance Calcium-Activated Potassium Channels ; metabolism ; Muscle, Smooth, Vascular ; drug effects ; metabolism ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; Proadifen ; pharmacology ; Rats ; Rats, Sprague-Dawley
4.Pilot study of using autologous bone marrow stromal cells and coral to repair canine segmental mandibular defects.
Jie YUAN ; Guang-peng LIU ; Gang CHAI ; Bo LIU ; Feng XU ; Lei CUI ; Wei LIU ; Yi-lin CAO
Chinese Journal of Plastic Surgery 2007;23(1):51-55
OBJECTIVETo repair segmental mandibular defects with autologous bone marrow stromal cells (BMSCs) engineered bone.
METHODSIsolated BMSCs were expanded in vitro and osteogenic induced. In 12 canines, a 3 cm segmental mandibular defect at right mandible was created. 6 canine's defects were repaired with cell-scaffold constructs made from induced BMSCs and coral; others were repaired with coral as control. The engineered bone was evaluated by X-ray, CT, Dual Energy X-ray Absorptiometry (DXA), gross and histological examination, and biomechanical test post-operatively.
RESULTSInduced BMSCs grew well on coral scaffold. At 12 weeks, X-ray showed more callus formed in experimental group, while evident scaffold duration in control group. At 32 weeks, gross observation, X-ray and CT demonstrated well bony-union in experimental group, while bony-nonunion in control group. Also DXA revealed significantly higher bone mineral density of experimental group than control group. Histologically, mature bone were commonly observed and there were bony healing in experimental group, while fibrous healing occurred in control group. Biomechanical test revealed no significant difference between experimental group and normal group.
CONCLUSIONSCanine segmental mandibular defects can be repaired with the tissue-engineered bone generated by coral scaffold with autologous osteogenic BMSCs.
Animals ; Anthozoa ; Bone Marrow Cells ; cytology ; Bone Substitutes ; Cell Culture Techniques ; Dogs ; Mandible ; pathology ; surgery ; Mesenchymal Stromal Cells ; cytology ; Pilot Projects ; Tissue Engineering ; Tissue Scaffolds ; Transplantation, Autologous
5.Epigenetic drug library screening reveals targeting DOT1L abrogates NAD+synthesis by reprogramming H3K79 methylation in uveal melanoma
Xiang GU ; Yu HUA ; Jie YU ; Ludi YANG ; Shengfang GE ; Renbing JIA ; Peiwei CHAI ; Ai ZHUANG ; Xianqun FAN
Journal of Pharmaceutical Analysis 2023;13(1):24-38
Uveal melanoma(UM)is the most frequent and life-threatening ocular malignancy in adults.Aberrant histone methylation contributes to the abnormal transcriptome during oncogenesis.However,a comprehensive understanding of histone methylation patterns and their therapeutic potential in UM remains enigmatic.Herein,using a systematic epi-drug screening and a high-throughput transcriptome profiling of histone methylation modifiers,we observed that disruptor of telomeric silencing-1-like(DOT1L),a methyltransferase of histone H3 lysine 79(H3K79),was activated in UM,especially in the high-risk group.Concordantly,a systematic epi-drug library screening revealed that DOT1 L inhibitors exhibited salient tumor-selective inhibitory effects on UM cells,both in vitro and in vivo.Combining Cleavage Under Targets and Tagmentation(CUT&Tag),RNA sequencing(RNA-seq),and bioinformatics analysis,we identified that DOT1 L facilitated H3K79 methylation of nicotinate phosphoribosyltransferase(NAPRT)and epigenetically activated its expression.Importantly,NAPRT served as an oncogenic accel-erator by enhancing nicotinamide adenine dinucleotide(NAD+)synthesis.Therapeutically,DOT1L inhi-bition epigenetically silenced NAPRT expression through the diminishment of dimethylation of H3K79(H3K79me2)in the NAPRT promoter,thereby inhibiting the malignant behaviors of UM.Conclusively,our findings delineated an integrated picture of the histone methylation landscape in UM and unveiled a novel DOT1L/NAPRT oncogenic mechanism that bridges transcriptional addiction and metabolic reprogramming.
6.Novel insights into histone lysine methyltransferases in cancer therapy:From epigenetic regulation to selective drugs
Qili LIAO ; Jie YANG ; Shengfang GE ; Peiwei CHAI ; Jiayan FAN ; Renbing JIA
Journal of Pharmaceutical Analysis 2023;13(2):127-141
The reversible and precise temporal and spatial regulation of histone lysine methyltransferases(KMTs)is essential for epigenome homeostasis.The dysregulation of KMTs is associated with tumor initiation,metastasis,chemoresistance,invasiveness,and the immune microenvironment.Therapeutically,their promising effects are being evaluated in diversified preclinical and clinical trials,demonstrating encouraging outcomes in multiple malignancies.In this review,we have updated recent understandings of KMTs'functions and the development of their targeted inhibitors.First,we provide an updated overview of the regulatory roles of several KMT activities in oncogenesis,tumor suppression,and im-mune regulation.In addition,we summarize the current targeting strategies in different cancer types and multiple ongoing clinical trials of combination therapies with KMT inhibitors.In summary,we endeavor to depict the regulation of KMT-mediated epigenetic landscape and provide potential epigenetic targets in the treatment of cancers.
7.Impact of potentially lethal ventricular arrhythmias on long-term outcome in patients with chronic heart failure.
Ye-hong LIU ; Jing-ying SU ; Lin-jie WANG ; Jin-ping LI ; Qing-fen ZHOU ; Qian GAN ; Xi-chen CHAI ; Li-ying DAI ; Feng-ru ZHANG ; Wei-feng SHEN
Chinese Medical Journal 2012;125(4):563-568
BACKGROUNDPotentially lethal ventricular arrhythmias (PLVAs) occur frequently in survivors after acute myocardial infarction and are increasingly recognized in other forms of structural heart diseases. This study investigated the prevalence and prognostic significance of PLVAs in patients with chronic heart failure (CHF).
METHODSData concerning demographics, etiology of heart failure, NYHA functional class, biochemical variables, electrocardiographic and echocardiographic findings, and medical treatments were collected by reviewing hospital medical records from 1080 patients with NYHA II-IV and a left ventricular (LV) ejection fraction ≤ 45%. PLVAs were defined as multi-focal ventricular ectopy (> 30 beats/h on Holter monitoring), bursts of ventricular premature beats, and nonsustained ventricular tachycardia. All-cause mortality, sudden death, and rehospitalization due to worsening heart failure, or cardiac transplantation during 5-year follow-up after discharge were recorded.
RESULTSThe occurrence rate of PLVAs in CHF was 30.2%, and increased with age; 23.4% in patients < 45 years old, 27.8% in those between 45 - 65 years old, and 33.5% in patients > 65 years old (P = 0.033). Patients with PLVAs had larger LV size and lower ejection fraction (both P < 0.01) and higher all-cause mortality (P = 0.014) during 5-year follow-up than those without PLVAs. Age (OR 1.041, 95%CI 1.004 - 1.079, P = 0.03) and LV end-diastolic dimension (OR 1.068, 95%CI 1.013 - 1.126, P = 0.015) independently predicted the occurrence of PLVAs. And PLVA was an independent factor for all-cause mortality (RR 1.702, 95%CI 1.017 - 2.848, P = 0.031) and sudden death (RR 1.937, 95%CI 1.068 - 3.516, P = 0.030) in patients with CHF.
CONCLUSIONPLVAs are common and exert a negative impact on long-term clinical outcome in patients with CHF.
Adult ; Aged ; Arrhythmias, Cardiac ; mortality ; physiopathology ; Electrocardiography ; Female ; Heart Failure ; physiopathology ; Humans ; Male ; Middle Aged ; Regression Analysis
8.Molecular mechanisms of diabetic coronary dysfunction due to large conductance Ca2⁺-activated K⁺ channel impairment.
Ru-Xing WANG ; Hai-Feng SHI ; Qiang CHAI ; Ying WU ; Wei SUN ; Yuan JI ; Yong YAO ; Ku-Lin LI ; Chang-Ying ZHANG ; Jie ZHENG ; Su-Xia GUO ; Xiao-Rong LI ; Tong LU
Chinese Medical Journal 2012;125(14):2548-2555
BACKGROUNDDiabetes mellitus is associated with coronary dysfunction, contributing to a 2- to 4-fold increase in the risk of coronary heart diseases. The mechanisms by which diabetes induces vasculopathy involve endothelial-dependent and -independent vascular dysfunction in both type 1 and type 2 diabetes mellitus. The purpose of this study is to determine the role of vascular large conductance Ca(2+)-activated K(+) (BK) channel activities in coronary dysfunction in streptozotocin-induced diabetic rats.
METHODSUsing videomicroscopy, immunoblotting, fluorescent assay and patch clamp techniques, we investigated the coronary BK channel activities and BK channel-mediated coronary vasoreactivity in streptozotocin-induced diabetic rats.
RESULTSBK currents (defined as the iberiotoxin-sensitive K(+) component) contribute (65 ± 4)% of the total K(+) currents in freshly isolated coronary smooth muscle cells and > 50% of the contraction of the inner diameter of coronary arteries from normal rats. However, BK current density is remarkably reduced in coronary smooth muscle cells of streptozotocin-induced diabetic rats, leading to an increase in coronary artery tension. BK channel activity in response to free Ca(2+) is impaired in diabetic rats. Moreover, cytoplasmic application of DHS-1 (a specific BK channel b(1) subunit activator) robustly enhanced the open probability of BK channels in coronary smooth muscle cells of normal rats. In diabetic rats, the DHS-1 effect was diminished in the presence of 200 nmol/L Ca(2+) and was significantly attenuated in the presence of high free calcium concentration, i.e., 1 mmol/L Ca(2+). Immunoblotting experiments confirmed that there was a 2-fold decrease in BK-b(1) protein expression in diabetic vessels, without altering the BK channel α-subunit expression. Although the cytosolic Ca(2+) concentration of coronary arterial smooth muscle cells was increased from (103 ± 23) nmol/L (n = 5) of control rats to (193 ± 22) nmol/L (n = 6, P < 0.05) of STZ-induced diabetic rats, reduced BK-b(1) expression made these channels less sensitive to intracellular Ca(2+), which in turn led to enhanced smooth muscle contraction.
CONCLUSIONSOur results indicated that BK channels are the key determinant of coronary arterial tone. Impaired BK channel function in diabetes mellitus is associated with down-regulation of BK-b(1) expression and reduction of the b(1)-mediated BK channel activation in diabetic vessels.
Animals ; Blotting, Western ; Coronary Vessels ; metabolism ; Diabetes Mellitus, Experimental ; metabolism ; physiopathology ; Diabetes Mellitus, Type 1 ; metabolism ; physiopathology ; Electrophysiology ; Large-Conductance Calcium-Activated Potassium Channels ; metabolism ; Male ; Muscle, Smooth, Vascular ; metabolism ; Rats ; Rats, Sprague-Dawley
9.Targeting RAS phosphorylation in cancer therapy: Mechanisms and modulators.
Yuran QIU ; Yuanhao WANG ; Zongtao CHAI ; Duan NI ; Xinyi LI ; Jun PU ; Jie CHEN ; Jian ZHANG ; Shaoyong LU ; Chuan LV ; Mingfei JI
Acta Pharmaceutica Sinica B 2021;11(11):3433-3446
RAS, a member of the small GTPase family, functions as a binary switch by shifting between inactive GDP-loaded and active GTP-loaded state. RAS gain-of-function mutations are one of the leading causes in human oncogenesis, accounting for ∼19% of the global cancer burden. As a well-recognized target in malignancy, RAS has been intensively studied in the past decades. Despite the sustained efforts, many failures occurred in the earlier exploration and resulted in an 'undruggable' feature of RAS proteins. Phosphorylation at several residues has been recently determined as regulators for wild-type and mutated RAS proteins. Therefore, the development of RAS inhibitors directly targeting the RAS mutants or towards upstream regulatory kinases supplies a novel direction for tackling the anti-RAS difficulties. A better understanding of RAS phosphorylation can contribute to future therapeutic strategies. In this review, we comprehensively summarized the current advances in RAS phosphorylation and provided mechanistic insights into the signaling transduction of associated pathways. Importantly, the preclinical and clinical success in developing anti-RAS drugs targeting the upstream kinases and potential directions of harnessing allostery to target RAS phosphorylation sites were also discussed.
10.Quality Evaluation and Reporting Specification for Real-World Studies of Traditional Chinese Medicine.
Qian-Yun CHAI ; Yu-Tong FEI ; Rui GAO ; Ru-Yu XIA ; Fang LU ; Ming-Jie ZI ; Ming-Yue SUN ; Zhong-Qi YANG ; Da-Fang CHEN ; Jian-Ping LIU
Chinese journal of integrative medicine 2022;28(12):1059-1062
In recent years, the real-world studies (RWS) have attracted extensive attention, and the real-world evidence (RWE) has been accepted to support the drug development in China and abroad. However, there is still a lack of standards for the evaluation of the quality of RWE. It is necessary to formulate a quality evaluation and reporting specification for RWE especially in traditional Chinese medicine (TCM). To this end, under the guidance of China Association of Chinese Medicine, the Quality Evaluation and Reporting Specification for Real-World Evidence of Traditional Chinese Medicine (QUERST) Group, including 24 experts (clinical epidemiologists, clinicians, pharmacologists, ethical reviewer and statisticians), was established to develop the specification. This specification contains the listing of classification of RWS design and RWE, the general principles and methods of RWE quality evaluation (26 tools or scales), 25 types of bias in RWS, the special considerations in evaluating the quality of RWE of TCM, and the 19 reporting standards of RWE. This specification aims to propose the quality evaluation principles and key points of RWE, and provide guidance for the proper use of RWE in the development of TCM new drugs.
Medicine, Chinese Traditional
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China