Identification and experimental validation of KMO as a critical immune-associated mitochondrial gene in unstable atherosclerotic plaque.

BACKGROUND: The heightened risk of cardiovascular and cerebrovascular events is associated with the increased instability of atherosclerotic plaques. However, the lack of effective diagnostic biomarkers has impeded the assessment of plaque instability currently. This study was aimed to investigate and identify hub genes associated with unstable plaques through the integration of various bioinformatics tools, providing novel insights into the detection and treatment of this condition. METHODS: Weighted Gene Co-expression Network Analysis (WGCNA) combined with two machine learning methods were used to identify hub genes strongly associated with plaque instability. The cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT) method was utilized to assess immune cell infiltration patterns in atherosclerosis patients. Additionally, Gene Set Variation Analysis (GSVA) was conducted to investigate the potential biological functions, pathways, and mechanisms of hub genes associated with unstable plaques. To further validate the diagnostic efficiency and expression of the hub genes, immunohistochemistry (IHC), quantitative real-time polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA) were performed on collected human carotid plaque and blood samples. Immunofluorescence co-staining was also utilized to confirm the association between hub genes and immune cells, as well as their colocalization with mitochondria. RESULTS: The CIBERSORT analysis demonstrated a significant decrease in the infiltration of CD8 T cells and an obvious increase in the infiltration of M0 macrophages in patients with atherosclerosis. Subsequently, two highly relevant modules (blue and green) strongly associated with atherosclerotic plaque instability were identified. Through intersection with mitochondria-related genes, 50 crucial genes were identified. Further analysis employing least absolute shrinkage and selection operator (LASSO) logistic regression and support vector machine recursive feature elimination (SVM-RFE) algorithms revealed six hub genes significantly associated with plaque instability. Among them, NT5DC3, ACADL, SLC25A4, ALDH1B1, and MAOB exhibited positive correlations with CD8 T cells and negative correlations with M0 macrophages, while kynurenine 3-monooxygenas (KMO) demonstrated a positive correlation with M0 macrophages and a negative correlation with CD8 T cells. IHC and RT-qPCR analyses of human carotid plaque samples, as well as ELISA analyses of blood samples, revealed significant upregulation of KMO and MAOB expression, along with decreased ALDH1B1 expression, in both stable and unstable samples compared to the control samples. However, among the three key genes mentioned above, only KMO showed a significant increase in expression in unstable plaque samples compared to stable plaque samples. Furthermore, the expression patterns of KMO in human carotid unstable plaque tissues and cultured mouse macrophage cell lines were assessed using immunofluorescence co-staining techniques. Finally, lentivirus-mediated KMO silencing was successfully transduced into the aortas of high-fat-fed ApoE-/- mice, with results indicating that KMO silencing attenuated plaque formation and promoted plaque stability in ApoE-/- mice. CONCLUSIONS: The results suggest that KMO, a mitochondria-targeted gene associated with macrophage cells, holds promise as a valuable diagnostic biomarker for assessing the instability of atherosclerotic plaques.

Non-invasive accelerated imaging through a scattering medium via multi-stage complexity guidance.

The research of scattering imaging is of great significance to the development of various fields, but the existing scattering imaging methods are difficult to combine for the advantages of non-invasiveness, real-time imaging, and high quality. In this paper, a new, to our knowledge, scattering imaging technique is proposed that optimizes the traditional autocorrelation imaging technique by multi-stage complexity guidance and the initial acceleration module. We introduce the complexity difference index into the phase iterative recovery step for effective complexity guidance, and add the initial module based on error-reduction iteration to realize a fast startup. A series of experiments is carried out to test the performance of the new technique. The results show that the proposed technique significantly improves the scattering reconstruction speed. Meanwhile, the accuracy and clarity of the reconstructed image are significantly higher than the traditional method in terms of fast imaging. Moreover, this technique has better robustness to noise compared to the traditional autocorrelation imaging technique. The experimental code for this paper is available on GitHub.

Effects of the multi-stress-resistant strain Zygosaccharomyces parabailii MC-5K3 bioaugmentation on microbial communities and metabolomics in tobacco waste extract.

Industrial tobacco waste was mainly treated via a reconstituted tobacco process using the paper-making method, which involves aqueous concentrated tobacco waste extract (cTWE) fermentation (aging). The fermentation was done to improve the quality of reconstituted tobacco. However, cTWE is a multi-stress environment that is characterized by low pH (about 4), as well as high sugar (above 150 g/L) and nicotine (above 15 g/L) content. In this study, a specific selection strategy was used to successfully isolate multi-stress-resistant bacterial or fungal strains, that exhibited positive effects on cTWE fermentation, thereby improving the quality of final products. A potential strain Zygosaccharomyces parabailii MC-5K3 was used for the bioaugmentation of cTWE fermentation and it significantly influenced the microbial diversity of the fermented cTWE. Zygosaccharomyces was observed to be the only dominant fungal genus instead of some pathogenic bacterial genera, with an abundance of over 95% after four days, and still more than 80% after a week. Meanwhile, metabolomics profiling showed significant concentration decrease with regard to some flavor-improving relative metabolites, such as 3-hydroxybenzoic acid (log2FC = - 5.25) and sorbitol (log2FC = - 5.54). This finding is extrapolated to be the key influence factor on the quality of the fermented cTWE. The correlation analysis also showed that the alterations in microbial diversity in the fermented cTWE led to some important differential metabolite changes, which finally improved various properties of tobacco products.

Single-cell RNA sequencing deciphers the mechanism of sepsis-induced liver injury and the therapeutic effects of artesunate.

Liver, as an immune and detoxification organ, represents an important line of defense against bacteria and infection and a vulnerable organ that is easily injured during sepsis. Artesunate (ART) is an anti-malaria agent, that also exhibits broad pharmacological activities including anti-inflammatory, immune-regulation and liver protection. In this study, we investigated the cellular responses in liver to sepsis infection and ART hepatic-protective mechanisms against sepsis. Cecal ligation and puncture (CLP)-induced sepsis model was established in mice. The mice were administered ART (10 mg/kg, i.p.) at 4 h, and sacrificed at 12 h after the surgery. Liver samples were collected for preparing single-cell RNA transcriptome sequencing (scRNA-seq). The scRNA-seq analysis revealed that sepsis-induced a dramatic reduction of hepatic endothelial cells, especially the subtypes characterized with proliferation and differentiation. Macrophages were recruited during sepsis and released inflammatory cytokines (Tnf, Il1b, Il6), chemokines (Ccl6, Cd14), and transcription factor (Nfkb1), resulting in liver inflammatory responses. Massive apoptosis of lymphocytes and abnormal recruitment of neutrophils caused immune dysfunction. ART treatment significantly improved the survival of CLP mice within 96 h, and partially relieved or reversed the above-mentioned pathological features, mitigating the impact of sepsis on liver injury, inflammation, and dysfunction. This study provides comprehensive fundamental proof for the liver protective efficacy of ART against sepsis infection, which would potentially contribute to its clinical translation for sepsis therapy. Single cell transcriptome reveals the changes of various hepatocyte subtypes of CLP-induced liver injury and the potential pharmacological effects of artesunate on sepsis.

Deterministic factors modulating assembly of groundwater microbial community in a nitrogen-contaminated and hydraulically-connected river-lake-floodplain ecosystem.

The river-lake-floodplain system (RLFS) undergoes intensive surface-groundwater mass and energy exchanges. Some freshwater lakes are groundwater flow-through systems, serving as sinks for nitrogen (N) entering the lake. Despite the threat of cross-nitrogen contamination, the assembly of the microbial communities in the RLFS was poorly understood. Herein, the distribution, co-occurrence, and assembly pattern of microbial community were investigated in a nitrogen-contaminated and hydraulically-connected RLFS. The results showed that nitrate was widely distributed with greater accumulation on the south than on the north side, and ammonia was accumulated in the groundwater discharge area (estuary and lakeshore). The heterotrophic nitrifying bacteria and aerobic denitrifying bacteria were distributed across the entire area. In estuary and lakeshore with low levels of oxidation-reduction potential (ORP) and high levels of total organic carbon (TOC) and ammonia, dissimilatory nitrate reduction to ammonium (DNRA) bacteria were enriched. The bacterial community had close cooperative relationships, and keystone taxa harbored nitrate reduction potentials. Combined with multivariable statistics and self-organizing map (SOM) results, ammonia, TOC, and ORP acted as drivers in the spatial evolution of the bacterial community, coincidence with the predominant deterministic processes and unique niche breadth for microbial assembly. This study provides novel insight into the traits and assembly of bacterial communities and potential nitrogen cycling capacities in RLFS groundwater.

[Effects of different drying methods on quality of male flowers of Eucommia ulmoides based on color and chemical composition].

To study the effects of different drying methods on the quality of male flowers of Eucommia ulmoides(MFOEU), we treated fresh MFOEU samples with drying in the shade(DS), vacuum freeze drying(VFD), high-or low-temperature hot air drying(HTHAD, LTHAD), microwave drying(MD), and vacuum drying(VD), respectively. The color, total flavonoid content, total polysaccharide content, and main active components such as geniposide, geniposidic acid, rutin, chlorogenic acid, galuteolin, pinoresinol diglucoside, and aucubin in MFOEU were taken as the evaluation indicators. The quality of MFOEU was comprehensively evaluated by entropy weight method combined with color index method, partial least squares discriminant analysis and content clustering heat map. The experimental results showed that VFD and DS basically kept the original color of MFOEU. The MFOEU treated with MD had higher content of total polysaccharides, phenylpropanoids, lignans, and iridoids. The MFOEU treated with LTHAD had higher content of total flavonoids and that treated with VD had lower content of active components. According to the results of comprehensive evaluation, the quality of MFOEU dried with different methods followed the order of MD>HTHAD>VFD>LTHAD>DS>VD. Considering the color of MFOEU, the suitable drying methods were DS and VFD. Considering the color, active components, and economic benefits of MFOEU, MD was the suitable drying method. The results of this study are of a reference value for the determination of suitable methods for MFOEU processing in the producing areas.

Creating an Aligned Interface between Nanoparticles and MOFs by Concurrent Replacement of Capping Agents.

Applying metal-organic frameworks (MOFs) on the surface of other materials to form multifunctional materials has recently attracted great attention; however, directing the MOF overgrowth is challenging due to the orders of magnitude differences in structural dimensions. In this work, we developed a universal strategy to mediate MOF growth on the surface of metal nanoparticles (NPs), by taking advantage of the dynamic nature of weakly adsorbed capping agents. During this colloidal process, the capping agents gradually dissociate from the metal surface, replaced in situ by the MOF. The MOF grows to generate a well-defined NP-MOF interface without a trapped capping agent, resulting in a uniform core-shell structure of one NP encapsulated in one single-crystalline MOF nanocrystal with specific facet alignment. The concept was demonstrated by coating ZIF-8 and UiO-66-type MOFs on shaped metal NPs capped by cetyltrimethylammonium surfactants, and the formation of the well-defined NP-MOF interface was monitored by spectroscopies. The defined interface outperforms ill-defined ones generated via conventional methods, displaying a high selectivity to unsaturated alcohols for the hydrogenation of an α,ß-unsaturated aldehyde. This strategy opens a new route to create aligned interfaces between materials with vastly different structural dimensions.

Effect of gal/GalNAc regioisomerism in galactosylated liposomes on asialoglycoprotein receptor-mediated hepatocyte-selective targeting in vivo.

In this study, we describe a novel synthesis of galactosylated lipids by lipase catalysis. Lactitol (Lac), galactose (Gal), or N-acetyl galactosamine (GalNAc) was coupled with cholesterol (CHS) as target head groups by enzyme-catalyzed regioselective esterification to produce three kinds of lipids: CHS-1-Gal, CHS-6-Gal, or CHS-6-GalNAc1. The biological effects of galactosylated lipids carrying different constitutional isomers of the pendent sugar species were investigated. LP-1-Gal (liposomes containing 5.0 molar% of CHS-1-Gal) showed strong binding to tetrameric lectins of Ricinus communis agglutinin (RCA120) in vitro, while LP-6-Gal (liposomes containing 5.0 molar% of CHS-6-Gal) and LP-6-GalNAc (liposomes containing 5.0 molar% of CHS-6-GalNAc) did not. After intravenous injection, LP-6-GalNAc, LP-1-Gal and LP-6-Gal rapidly disappeared from the blood and accumulated rapidly in liver (up to 74.88 ± 4.11%, 58.67 ± 5.75%, and 47.66 ± 4.56% of injected dose/g organ within 4 h, respectively). This is significantly higher than the uptake of unmodified liposomes (Unmod-LP) (18.67 ± 6.07%). Pre-injection of asialofetuin significantly inhibits liver uptake of Gal-liposomes (P < 0.01), with the degree of inhibition appearing in the following order: LP-6-GalNAc (73.29%) > LP-1-Gal (67.06%) > LP-6-Gal (53.61%). More importantly, LP-6-GalNAc was preferentially taken up by hepatocytes and the uptake ratio by parenchymal cells (PC) and nonparenchymal cells (NPC) (PC/NPC ratio) was 11.03 higher than LP-1-Gal (7.32), LP-6-Gal (5.83) and Unmod-LP (2.39). We suggest that liposomes containing the novel galactosylated lipid CHS-6-GalNAc have potential as drug delivery carriers for hepatocyte-selective targeting.

Probing Interactions between Metal-Organic Frameworks and Freestanding Enzymes in a Hollow Structure.

It has been reported that the biological functions of enzymes could be altered when they are encapsulated in metal-organic frameworks (MOFs) due to the interactions between them. Herein, we probed the interactions of catalase in solid and hollow ZIF-8 microcrystals. The solid sample with confined catalase is prepared through a reported method, and the hollow sample is generated by hollowing the MOF crystals, sealing freestanding enzymes in the central cavities of hollow ZIF-8. During the hollowing process, the samples were monitored by small-angle X-ray scattering (SAXS) spectroscopy, electron microscopy, powder X-ray diffraction (PXRD), and nitrogen sorption. The interfacial interactions of the two samples were studied by infrared (IR) and fluorescence spectroscopy. IR study shows that freestanding catalase has less chemical interaction with ZIF-8 than confined catalase, and a fluorescence study indicates that the freestanding catalase has lower structural confinement. We have then carried out the hydrogen peroxide degradation activities of catalase at different stages and revealed that the freestanding catalase in hollow ZIF-8 has higher activity.

[Platelet function tests and Chinese medicines with antiplatelet function:a review].

Platelet function tests have been increasingly used to assist in the diagnosis of platelet disorders and prethrombotic state, monitoring of the efficacy of antiplatelet therapies, and personalized treatment. On the basis of light transmission aggregometry, new methods for platelet function test have been developed successively. At present, the research and development of platelet function detector is in its infancy in China. The active constituents of antiplatelet Chinese medicines can be classified into terpenoids, flavonoids, saponins, organic acids, lignans, diketones, volatile oils, and stilbenes. The results of dose-antiplatelet effect relationship of Chinese medicines and the active constituents showed that the effective concentration of the extracts or monomers of Chinese medicines was at micromolar level(µmol·L~(-1)), among which salvianolic acid B and ginkgolide K, ginkgolide B, and ginkgolide A had the strongest antiplatelet effect. These results suggest that the antiplatelet effect of Chinese medicine may be weaker than that of chemical drugs and biological products. Therefore, it is necessary to explore the structure-activity relationship of the active constituents in existing Chinese medicines and further improve their efficacy through structure modification. The antiplatelet effect of Chinese medicines and the constituents involves multiple pathways and multiple targets. These research results provide a reference for clinical application of them. However, there is still a lack of large-scale multi-center clinical trials to confirm the efficacy and safety of them. The regularity of the relationship between the structures of various constituents and their corresponding functions is still unknown and the relevant signal transduction pathways and structure-activity relationship need to be further studied. This paper summarized and analyzed the determination methods of platelet functions and the research results of antiplatelet Chinese medicines, which is of reference value for the research of effective and safe antiplatelet Chinese medicines.

Genes associated with inflammation may serve as biomarkers for the diagnosis of coronary artery disease and ischaemic stroke.

BACKGROUND: The current research aimed to expound the genes and pathways that are involved in coronary artery disease (CAD) and ischaemic stroke (IS) and the related mechanisms. METHODS: Two array CAD datasets of (GSE66360 and GSE97320) and an array IS dataset (GSE22255) were downloaded. Differentially expressed genes (DEGs) were identified using the limma package. The online tool Database for Annotation, Visualization and Integrated Discovery (DAVID) (version 6.8; david.abcc.ncifcrf.gov) was used to annotate the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) enrichment analyses of the DEGs. A protein-protein interaction (PPI) network was constructed by Cytoscape software, and then Molecular Complex Detection (MCODE) analysis was used to screen for hub genes. The hub genes were also confirmed by RT-qPCR and unconditional logistic regression analysis in our CAD and IS patients. RESULTS: A total of 20 common DEGs (all upregulated) were identified between the CAD/IS and control groups. Eleven molecular functions, 3 cellular components, and 49 biological processes were confirmed by GO enrichment analysis, and the 20 common upregulated DEGs were enriched in 21 KEGG pathways. A PPI network including 24 nodes and 68 edges was constructed with the STRING online tool. After MCODE analysis, the top 5 high degree genes, including Jun proto-oncogene (JUN, degree = 9), C-X-C motif chemokine ligand 8 (CXCL8, degree = 9), tumour necrosis factor (TNF, degree = 9), suppressor of cytokine signalling 3 (SOCS3, degree = 8) and TNF alpha induced protein 3 (TNFAIP3, degree = 8) were noted. RT-qPCR results demonstrated that the expression levels of CXCL8 were increased in IS patients than in normal participants and the expression levels of SOCS3, TNF and TNFAIP were higher in CAD/IS patients than in normal participants. Meanwhile, unconditional logistic regression analysis revealed that the incidence of CAD or IS was positively correlated with the CXCL8, SOCS3, TNF and TNFAIP3. CONCLUSIONS: The CXCL8, TNF, SOCS3 and TNFAIP3 associated with inflammation may serve as biomarkers for the diagnosis of CAD or IS. The possible mechanisms may involve the Toll-like receptor, TNF, NF-kappa B, cytokine-cytokine receptor interactions and the NOD-like receptor signalling pathways.

[Effects of Xueshuantong Injection on thrombosis formation and blood flow in rats].

The aim of this paper was to explore the effect of Xueshuantong Injection(freeze-dried powder,XST) on κ-carrageenan-induced thrombosis and blood flow from the aspects of interactions among blood flow,vascular endothelium and platelets. Fifty male Sprague-Dawley rats(190-200 g) were randomized into five groups: control group, model group, heparin sodium(1 000 U·kg~(-1)) group, low-dose and high-dose(50, 150 mg·kg~(-1)) XST groups. Rats were intraperitoneally injected with corresponding drugs and normal saline(normal control and model groups) for 10 days. One hour after drugs were administered intraperitoneally on the 7 th day, each rat was injected with κ-carrageenan(Type Ⅰ, 1 mg·kg~(-1)) which was dissolved in physiological saline by intravenous administration in the tail to establish tail thrombus model. The lengths of black tails of the rats were measured at 2, 6, 24 and 48 h after modeling. Vevo®2100 small animal ultrasound imaging system was used to detect the internal diameter of rat common carotid artery, blood flow velocity and heart rate, and then the blood flow and shear rate were calculated. Meanwhile, the microcirculatory blood flow perfusion in the thigh surface and tail of rats were detected by laser speckle blood flow imaging system. Platelet aggregometry was used to detect the max platelet aggregation rate in rats. Pathological changes in tail were observed through hematoxylin-eosin staining, and Western blot was used to detect the protein content of platelet piezo1. According to the results, XST could inhibit the rat tail arterial thrombosis and significantly reduce the length of black tail(P<0.05). The blood flow of common carotid artery in XST low dose group was significantly higher than that in the model group(P<0.05). XST high dose group could significantly increase the microcirculatory blood flow perfusion of the tail in rats as compared with the model group(P<0.05). XST high dose group could significantly inhibit platelet aggregation rate(P<0.05) and XST low dose group could significantly inhibit platelet piezo1 protein expression(P<0.01). In summary, XST could play an effect in fighting against thrombosis induced by κ-carrageenan in rats, which may be related to significantly inhibiting platelet aggregation, improving body's blood flow state, maintaining normal hemodynamic environment and affecting mechanical ion channel protein piezo1.

Protection and Prevention of Age-Related Hearing Loss.

Presbycusis is a sensorineural hearing loss caused by hearing system aging and degeneration. The clinical manifestations are progressive bilateral symmetrical hearing loss, and the hearing curve is mostly slope-shaped with high-frequency reduction, sometimes flat. The results of the second national sample survey of disabled persons (2006) showed that the total number of hearing and speech disability in China was 27.8 million, accounting for 34% of the total number of disabled people in China. Among them are people over 60 years old. There are 20.4541 million people with hearing disabilities. There are 9.49 million senile deaf patients, accounting for 34.1% of the total number of hearing disabilities. As society gradually becomes aging, the incidence of presbycusis is getting higher and higher. The study of its pathogenesis is of great significance for the diagnosis, treatment, and prevention of presbycusis. The rapid progress of molecular biology experimental technology has provided us with a new opportunity to fully understand and reveal the presbycusis. In the near future, early diagnosis of presbycusis-related genes and early prevention or delay of the occurrence and development of presbycusis will become a reality.

A New Species of Sulcospira (Gastropoda: Pachychilidae) from Hunan, China.

A new species of pachychilid freshwater gastropod, Sulcospira hunanensis sp. nov., is described from Hunan Province, China, based on morphological and molecular evidence. The new species is distinguished from its congeners by a combination of characters, including elongated shell with eight to nine whorls, spiral whorls with ribs, and stomach with outer and inner crescentic pads not connected to each other. Sulcospira hunanensis sp. nov. is the first confirmed report of this genus from Hunan Province, China. It is anticipated that further species will be found in this region, which currently remain unknown. Furthermore, based on morphological and molecular evidence, this study is the first record of Sulcospira tonkiniana in Guangxi Zhuang Autonomous Region, China, with Sulcospira krempfi supported as a synonym of Sulcospira tonkiniana.

[Development of bioassay method in quality control of traditional Chinese medicine].

On the basis of chemical content determination， the bioassay methods can be used to comprehensively evaluate and control the Chinese medicine compound. This paper analyzed the newly published literature on traditional Chinese medicine(TCM) bioassay. The selection of standard control substances and the establishment of experimental system are the main difficulties in bioassay. At present， the standard control substances mainly include： different sources of products with basically similar components， certified medicinal materials， genuine medicinal materials， commonly used chemical drugs or biological products with similar pharmacological functions， as well as Chinese medicine potency conversed by activity of biological products. In this paper， the common bioassays would be summarized from the clinical efficacy of activating blood circulation and removing stasis and clearing heat and detoxification. It is one of the important contents in the industrial production of traditional Chinese medicine to gradually establish the bioassay platform of Chinese medicine from the enterprise's internal control to the industry. recognition.

Shielding against Unfolding by Embedding Enzymes in Metal-Organic Frameworks via a de Novo Approach.

We show that an enzyme maintains its biological function under a wider range of conditions after being embedded in metal-organic framework (MOF) microcrystals via a de novo approach. This enhanced stability arises from confinement of the enzyme molecules in the mesoporous cavities in the MOFs, which reduces the structural mobility of enzyme molecules. We embedded catalase (CAT) into zeolitic imidazolate frameworks (ZIF-90 and ZIF-8), and then exposed both embedded CAT and free CAT to a denature reagent (i.e., urea) and high temperatures (i.e., 80 °C). The embedded CAT maintains its biological function in the decomposition of hydrogen peroxide even when exposed to 6 M urea and 80 °C, with apparent rate constants kobs (s-1) of 1.30 × 10-3 and 1.05 × 10-3, respectively, while free CAT shows undetectable activity. A fluorescence spectroscopy study shows that the structural conformation of the embedded CAT changes less under these denaturing conditions than free CAT.

[Anti-platelet adhesive effect and mechanisms of Xueshuantong capsules under flow conditions].

To investigate the anti-platelet adhesive effect and possible mechanisms of Xueshuantong capsule (XST) under flow conditions. Human umbilical vein endothelial cells (HUVECs) and human platelets were employed as experimental materials, and TNF-α (20 µg•L⁻¹) was used to establish vascular endothelial cell injury models. In vivo flow conditions were simulated under controlled shear stress of 0.1 Pa and 0.9 Pa by Bioflux1000 assays accordingly. Anti-platelet adhesive effects of XST at 0.3 g•L⁻¹ were dynamically monitored by microscopic time-lapse photography. Western blotting was employed to detect the VCAM-1 expression on endothelial cells, and the release of 6-keto-PGF1α and TXB2 was tested by radioimmunoassay. The results showed that XST could inhibit the platelets adhesion under both physiological and pathological flow conditions, and the inhibition rate was 15.0% and 34.1% respectively. Under pathological low shear stress or static conditions, XST could significantly inhibit endothelial cells VCAM-1 expression and TXB2 release (P<0.05). These results suggested that XST inhibited platelets adhering to injured endothelium via decreasing VCAM-1 expression and TXA2 secretion from endothelium. From the interactions among blood flow, vascular endothelium and platelets, the anti-thrombosis effects of XST were possibly related to endothelial cells protection and therefore inhibiting platelets adhesion. Under different flow conditions, the antiplatelet adhesion effect of XST was different, and the pathological low shear stress was more conducive to the efficacy of XST.

Highly Stereoselective Gold-Catalyzed Coupling of Diazo Reagents and Fluorinated Enol Silyl Ethers to Tetrasubstituted Alkenes.

We report a highly stereoselective synthesis of all-carbon or fluorinated tetrasubstituted alkenes from diazo reagents and fluorinated enol silyl ethers, using C-F bond as a synthetic handle. Cationic AuI catalysis plays a key role in this reaction. Remarkable fluorine effects on the reactivity and selectivity was also observed.