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To realize high-throughput tensile testing of miniaturized specimens, the size effect was investigated. High-throughput tensile testing was used to characterize the mechanical properties of steel in the micro-zone. Miniaturized specimens with diameters ranging from 0.7 mm to 2.5 mm were cut from low-alloyed steel and tested, and the deviations between the results of miniaturized and conventional sized specimens were examined. The results showed that the size effect was negligibly small for the tensile strength. However, the upper yield strength, lower yield strength, and plastic extension strength of miniaturized specimens decreased as the specimen diameter decreased. It was found that a diameter of 1.5 mm was critical for the tensile testing of miniaturized specimens. As the specimen diameter decreased toward 1.5 mm, the strength parameters gradually decreased, and as the specimen diameter further decreased from 1.5 mm, the strength parameters increased. In contrast, as the specimen diameter decreased from 1.3 mm, the elongation after fracture decreased. However, the percentage reduction of area did not vary between miniaturized and conventional sized specimens.

Argonaute 2 (Ago2) is an essential component of the RNA-induced silencing complex (RISC) and it participates in diverse physiological processes, while dysregulation of Ago2 activity is closely linked to a variety of human diseases including cancers. The reported Ago2 assays often suffer from laborious procedures, complicated reaction schemes, and unsatisfactory sensitivity. Herein, we develop a new gold nanoparticle (AuNP)-based single-molecule biosensor for simple and sensitive detection of Ago2 activity. The Ago2-responsive AuNP nanoprobe is constructed through the self-assembly of multiple Cy5-labeled signal probes onto the AuNP, in which the Cy5 fluorescence is efficiently quenched by the AuNP. Target Ago2 can bind with guide RNA to form an active RISC, inducing the cyclic cleavage of the signal probes and the release of Cy5 moieties from the AuNP nanoprobe. The released Cy5 molecules can be simply quantified by single-molecule counting. This single-molecule biosensor enables detection of Ago2 activity with the involvement of only a single AuNP nanoprobe, eliminating the use of any extra antibodies and protein enzymes. This single-molecule biosensor achieves good specificity and high sensitivity with a detection limit of 9.1 pM, and it can be exploited for the screening of Ago2 inhibitors, Ago2 kinetic analysis, and the imaging of intracellular Ago2 activity in live cells, holding great promise in Ago2-related biomedical research and clinical diagnosis.

Lipid droplets (LDs), which are neutral lipid storage organelles, are important for lipid metabolism and energy homeostasis. LD lipolysis and interactions with mitochondria are tightly coupled to cellular metabolism and may be potential targets to buffer the effects of excessive toxic lipid species levels. Acetylcholine (ACh), the major neurotransmitter of the vagus nerve, exhibits cardioprotective effects. However, limited research has focused on its effects on LD lipolysis and the LD-mitochondria association in fatty acid (FA) overload models. Here, we reveal that palmitate (PA) induces an increase in expression of the FA transport protein cluster of differentiation 36 (CD36) and LD formation; remarkably reduces the expression of lipases involved in triacylglycerol (TAG) lipolysis, such as adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL) and monoacylglycerol lipase (MGL); impairs LD-mitochondria interaction; and decreases perilipin 5 (PLIN5) expression, resulting in LD accumulation and mitochondrial dysfunction, which ultimately lead to cardiomyocyte apoptosis. ACh significantly upregulates PLIN5 expression and improved LD lipolysis and the LD-mitochondria association. Moreover, ACh reduces CD36 expression, LD deposition and mitochondrial dysfunction, ultimately suppressing apoptosis in PA-treated neonatal rat ventricular cardiomyocytes (NRVCs). Knockdown of PLIN5, which plays a role in LD-mitochondria contact site formation, abolishes the protective effects of ACh in PA-treated NRVCs. Thus, ACh protects cardiomyocytes from PA-induced apoptosis, at least partly, by promoting LD lipolysis and activating LD-mitochondria interactions via PLIN5. These findings may aid in developing novel therapeutic approaches that target LD lipolysis and PLIN5-mediated LD-mitochondria interactions to prevent or alleviate lipotoxic cardiomyopathy.

N6-methyladenosine modification as an mRNA modification in mammalian cells is dynamically reversible, regulated by RNA demethylase [e.g., fat mass and obesity-associated protein (FTO)]. The abnormal expression of FTO is closely related to numerous diseases (e.g., various cancers and obesity). Herein, we demonstrate the single-molecule counting of FTO in human cancer cells and breast tissues based on a T7 RNA polymerase-mediated rolling circle transcription (RCT) amplification-driven clustered regularly interspaced short palindromic repeat (CRISPR)─Cas12a. When FTO is present, it demethylates the DNA substrate, initiating the DpnII-mediated cleavage reaction. After magnetic separation, the cleaved DNA fragments trigger the T7 RNA polymerase-mediated RCT amplification, activating CRISPR-/Cas12a-mediated cleavage of signal probes and releasing abundant FAM molecules that are simply counted via single-molecule detection. In this assay, only target FTO can generate CRISPR RNAs, efficiently improving detection specificity. Moreover, the integration of single-molecule detection with magnetic separation achieves zero background and effectively enhances detection sensitivity. This method can specifically and sensitively monitor FTO activity with a limit of detection of 1.20 × 10

5-Hydroxymethylcytosine (5hmC) modification is a key epigenetic regulator of cellular processes in mammalian cells, and its misregulation may lead to various diseases. Herein, we develop a hydroxymethylation-specific ligation-mediated single quantum dot (QD)-based fluorescence resonance energy transfer (FRET) nanosensor for sensitive quantification of 5hmC modification in cancer cells. We design a Cy5-modified signal probe and a biotinylated capture probe for the recognition of specific 5hmC-containing genes. 5hmC in target DNA can be selectively converted by T4 β-glucosyltransferase to produce a glycosyl-modified 5hmC, which cannot be cleaved by methylation-insensitive restriction enzyme MspI. The glycosylated 5hmC DNA may act as a template to ligate a signal probe and a capture probe, initiating hydroxymethylation-specific ligation to generate large amounts of biotin-/Cy5-modified single-stranded DNAs (ssDNAs). The assembly of biotin-/Cy5-modified ssDNAs onto a single QD through streptavidin-biotin interaction results in FRET and consequently the generation of a Cy5 signal. The nanosensor is very simple without the need for bisulfite treatment, radioactive reagents, and 5hmC-specific antibodies. Owing to excellent specificity and high amplification efficiency of hydroxymethylation-specific ligation and near-zero background of a single QD-based FRET, this nanosensor can quantify 5hmC DNA with a limit of detection of 33.61 aM and a wider linear range of 7 orders of magnitude, and it may discriminate the single-nucleotide difference among 5hmC, 5-methylcytosine, and unmodified cytosine. Moreover, this nanosensor can distinguish as low as a 0.001% 5hmC DNA in complex mixtures, and it can monitor the cellular 5hmC level and discriminate cancer cells from normal cells, holding great potential in biomedical research and clinical diagnostics.

MicroRNAs (miRNAs) play key roles in the post-transcriptional regulation of genes, and their aberrant expression may disturb the normal gene regulation network to induce various diseases, and thus accurate detection of miRNAs is essential to early clinical diagnosis. Herein, we develop for the first time a single-quantum dot (QD)-based Förster resonance energy transfer (FRET) nanosensor to accurately detect miRNAs based on copper-free and enzyme-free cycling click chemistry-mediated tricyclic ligase chain reaction (LCR) amplification. We design four DNA probes namely DNA probes 1–4, with DNA probes 1 and 3 being modified with azide (N3) and DNA probes 2 and 4 being modified with dibenzocyclooctyne (DBCO). When target miRNA is present, DNA probes 1 and 2 can proceed via copper-free and enzyme-free click chemistry to generate the probes 1–2 ligation product. Subsequently, DNA probes 3 and 4 can hybridize with the probes 1–2 ligation product to generate the probes 3–4 ligation product. Both the probes 1–2 ligation product and probes 3–4 ligation product can act as the templates to initiate cycling click chemistry-mediated tricyclic LCR amplification whose products can be easily measured by the single-QD-based FRET nanosensor. This assay does not involve any enzymatic reverse transcription, copper catalyst, and ligase enzyme, and it exhibits excellent selectivity, high sensitivity, and the capability of differentiating even single-base mismatches. Moreover, this nanosensor can accurately quantify miRNA-155 even at the single-cell level, and it can distinguish the miRNA-155 expression in tissues of healthy persons and nonsmall cell lung cancer (NSCLC) patients., A copper-free and enzyme-free click chemistry-mediated single quantum dot nanosensor enables sensitive detection of microRNAs in cancer cells and tissues.

The disruption of gut microbes is associated with diabetic cardiomyopathy, but the mechanism by which gut microbes affect cardiac damage remains unclear. We explored gut microbes and branched-chain amino acid (BCAA) metabolite catabolism in diabetic cardiomyopathy mice and investigated the cardioprotective effect of pyridostigmine. The experiments were conducted using a model of diabetic cardiomyopathy induced by a high-fat diet + streptozotocin in C57BL/6 mice. The results of high-throughput sequencing showed that diabetic cardiomyopathy mice exhibited decreased gut microbial diversity, altered abundance of the diabetes-related microbes, and increased abundance of the BCAA-producing microbes Clostridiales and Lachnospiraceae. In addition, diabetes downregulated tight junction proteins (ZO-1, occludin, and claudin-1) and increased intestinal permeability to impair the intestinal barrier. These impairments were accompanied by reduction in vagal activity that manifested as increased acetylcholinesterase levels, decreased acetylcholine levels, and heart rate variability, which eventually led to cardiac damage. Pyridostigmine enhanced vagal activity, restored gut microbiota homeostasis, decreased BCAA-producing microbe abundance, and improved the intestinal barrier to reduce circulating BCAA levels. Pyridostigmine also upregulated BCAT2 and PP2Cm and downregulated p-BCKDHA/BCKDHA and BCKDK to improve cardiac BCAA catabolism. Moreover, pyridostigmine alleviated abnormal mitochondrial structure; increased ATP production; decreased reactive oxygen species and mitochondria-related apoptosis; and attenuated cardiac dysfunction, hypertrophy, and fibrosis in diabetic cardiomyopathy mice. In conclusion, the gut microbiota, BCAA catabolism, and vagal activity were impaired in diabetic cardiomyopathy mice but were improved by pyridostigmine. These results provide novel insights for the development of a therapeutic strategy for diabetes-induced cardiac damage that targets gut microbes and BCAA catabolism.

Insulin resistance and autonomic imbalance are important pathological processes in metabolic syndrome-induced cardiac remodeling. Recent studies determined that disruption of mitochondrial cristae shape is associated with myocardial ischemia; however, the change in cristae shape in metabolic syndrome-induced cardiac remodeling remains unclear. This study determined the effect of pyridostigmine (PYR), which reversibly inhibits cholinesterase to improve autonomic imbalance, on high-fat diet (HFD)-induced cardiac insulin resistance and explored the potential effect on the shape of mitochondrial cristae. Feeding of a HFD for 22 weeks led to an irregular and even lysed cristae structure in cardiac mitochondria, which contributed to decreased mitochondrial content and ATP production and increased oxygen species production, ultimately impairing insulin signaling and lipid metabolism. Interestingly, PYR enhanced vagal activity by increasing acetylcholine production and exerted mito-protective effects by activating the LKB1/AMPK/ACC signal pathway. Specifically, PYR upregulated OPA1 and Mfn1/2 expression, promoted the formation of the mitofilin/CHCHD3/Sam50 complex, and decreased p-Drp1 and Fis1 expression, resulting in tight and parallel cristae and increasing cardiac mitochondrial complex subunit expression and ATP generation as well as decreasing release of cytochrome C from mitochondria and oxidative damage. Furthermore, PYR improved glucose and insulin tolerance and insulin-stimulated Akt phosphorylation, decreased lipid toxicity, and ultimately ameliorated HFD-induced cardiac remodeling and dysfunction. In conclusion, PYR prevented cardiac and insulin insensitivity and remodeling by stimulating vagal activity to regulate mitochondrial cristae shape and function in HFD-induced metabolic syndrome in mice. These results provide novel insights for the development of a therapeutic strategy for obesity-induced cardiac dysfunction that targets mitochondrial cristae.

Composition-graded materials could be designed to rapidly establish the structure-property with high-throughput methods. In this study, stainless steel 316L(SS316L) - 431(SS431) graded material with the SS316L content ranging from 0 to 100 wt.% was fabricated by directed energy deposition additive manufacturing. Composition, phase constitution, microstructure and corrosion behavior of the graded material were characterized by laser-induced breakdown spectroscopy (LIBS), micro-beam X-ray diffraction (XRD), scanning electron microscope (SEM) and high-throughput local electrochemical techniques respectively. The results show that the relative amount of γ-Fe phase increases with the increasing SS316L content, leading to a noticeable decline of microhardness from 578 to 205 HV. Accordingly, the dominant microstructure varies from equiaxed dendrites to a mixture of dendritic and cellular structures. As the content of SS316L increases, the reduced carbides at grain boundaries and the increasing compactness of passive film improve the general and pitting corrosion resistance of the material. When the SS316L content is higher than 50 wt.%, the Volta potential and pitting susceptibility are similar to the pure SS316L part, while the microhardness is higher. Such a high-throughput screening process allows one to reliably select the constituents with the presence of SS316L over 50 wt.% as a potential component under the requirement of high corrosion resistance and wear resistance.

Mitochondrial dynamics—fission and fusion—are associated with ischaemic heart disease (IHD). This study explored the protective effect of vagal nerve stimulation (VNS) against isoproterenol (ISO)‐induced myocardial ischaemia in a rat model and tested whether VNS plays a role in preventing disorders of mitochondrial dynamics and function. Isoproterenol not only caused cardiac injury but also increased the expression of mitochondrial fission proteins [dynamin‐related peptide1 (Drp1) and mitochondrial fission protein1 (Fis‐1)) and decreased the expression of fusion proteins (optic atrophy‐1 (OPA1) and mitofusins1/2 (Mfn1/2)], thereby disrupting mitochondrial dynamics and leading to increase in mitochondrial fragments. Interestingly, VNS restored mitochondrial dynamics through regulation of Drp1, Fis‐1, OPA1 and Mfn1/2; enhanced ATP content and mitochondrial membrane potential; reduced mitochondrial permeability transition pore (MPTP) opening; and improved mitochondrial ultrastructure and size. Furthermore, VNS reduced the size of the myocardial infarction and ameliorated cardiomyocyte apoptosis and cardiac dysfunction induced by ISO. Moreover, VNS activated AMP‐activated protein kinase (AMPK), which was accompanied by phosphorylation of Ca2+/calmodulin‐dependent protein kinase kinase β (CaMKKβ) during myocardial ischaemia. Treatment with subtype‐3 of muscarinic acetylcholine receptor (M3R) antagonist 4‐diphenylacetoxy‐N‐methylpiperidine methiodide or AMPK inhibitor Compound C abolished the protective effects of VNS on mitochondrial dynamics and function, suggesting that M3R/CaMKKβ/AMPK signalling are involved in mediating beneficial effects of VNS. This study demonstrates that VNS modulates mitochondrial dynamics and improves mitochondrial function, possibly through the M3R/CaMKKβ/AMPK pathway, to attenuate ISO‐induced cardiac damage in rats. Targeting mitochondrial dynamics may provide a novel therapeutic strategy in IHD.

Aluminum nitride (AlN) film as a piezoelectric material has been used widely, particularly in vibration energy harvester due to its unique and enhanced properties such as high temperature resistance and compatibility with CMOS processes. In this work, AlN film with (002) preferred orientation was prepared on silicon wafers by pulse DC reactive magnetron sputtering (RMS), and the properties such as peak intensity, full width at half maximum (FWHM) and surface morphology were investigated by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The preferred orientation was found to be sensitive to deposition conditions such as gas flow rate, power, bottom electrodes materials and substrates temperature. The results shows that the intensity was 1.1×105 counts, the FWHM was 1.9owhen the temperature was 260°C. The film was used to fabricate the vibrated energy harvester successful and the power density reached about 3000uW/cm3 at the vibration frequency under 1g acceleration.

Background: Excessive activation of matrix metalloproteinase 9 (MMP-9) has been found in several inflammatory diseases. Previous studies have shown that acetylcholine (ACh) reduced the levels of pro-inflammatory cytokines and decreased tissue damage. Therefore, this study was designed to explore the potential effects and mechanisms of ACh on MMP-9 production and cell migration in response to lipopolysaccharide (LPS) stimulation in RAW264.7 cells. Methods: MMP-9 expression and activity were induced by LPS in RAW264.7 cells, and examined by real-time PCR, western blotting and gelatin zymography, respectively. ELISA was used to determine the changes in MMP-9 secretion among the groups. Macrophage migration was evaluated using transwell migration assay. Knockdown of a7 nicotinic acetylcholine receptor (a7 nAChR) expression was performed using siRNA transfection. Results: Pre-treatment with ACh inhibited LPS-induced MMP-9 production and macrophage migration in RAW264.7 cells. These effects were abolished by the a7 nAChR antagonist methyllycaconitine (MLA) and a7 nAChR siRNA. The a7 nAChR agonist PNU282987 was found to have an effect similar to that of ACh. Moreover, ACh enhanced the expression of JAK2 and STAT3, and the JAK2 inhibitor AG490 and the STAT3 inhibitor static restored the effect of ACh. Meanwhile, ACh decreased the phosphorylation and nuclear translocation of NF-κB, and this effect was abrogated in the presence of MLA. In addition, the JAK2 and STAT3 inhibitor abolished the inhibitory effects of ACh on phosphorylation of NF-κB. Conclusions: Activation of a7 nAChR by ACh inhibited LPS-induced MMP-9 production and macrophage migration through the JAK2/STAT3 signaling pathway. These results provide novel insights into the anti-inflammatory effects and mechanisms of ACh.

Previous findings have shown that acetylcholine (ACh) decreased hypoxia-induced tumor necrosis factor alpha (TNF α) production, thus protected against cardiomyocyte injury. However, whether and how ACh affects TNF α-induced endoplasmic reticulum (ER) stress and cell apoptosis remain poorly defined. This study was aimed at determining the effect of ACh in H9c2 cells after TNF α stimulation. Presence of ER stress was verified using the ER stress protein markers glucose regulatory protein 78 (GRP78) and C/EBP homologous protein (CHOP). Cell apoptosis was shown by caspase-3 activation and terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling. Exogenously administered ACh significantly decreased these TNF α-induced changes. Moreover, when the cells were exposed to nonspecific muscarinic receptor (M AChR) inhibitor atropine, methoctramine (M2 AChR inhibitor) or the epidermal growth factor receptor (EGFR) inhibitor AG1478, the cardioprotection elicited by ACh was diminished. Furthermore, the above effects were also blocked by M2 AChR or EGFR siRNA, indicating that EGFR transactivation by M2 AChR may be the major pathway responsible for the benefits of ACh. In addition, LY294002, a phosphatidylinositol-3-kinase (PI3K) inhibitor, displayed the similar trends as AG1478, suggesting that PI3K/Akt signaling may be the downstream of EGFR in ACh-elicited anti-apoptotic property. Together, these data indicate that EGFR-PI3K/Akt signaling is involved in M2 AChR-mediated ER apoptotic pathway suppression and the subsequent survival of H9c2 cardiomyocytes. We have identified a novel pathway underlying the cardioprotection afforded by ACh.

It is well-accepted that inflammation plays an important role in the development of cardiac remodelling and that therapeutic approaches targeting inflammation can inhibit cardiac remodelling. Although a large amount of evidence indicates that activation of α7 nicotinic acetylcholine receptor (α7nAChR) causes an anti-inflammatory effect, the role of α7nAChR in cardiac remodelling and the underlying mechanism have not been established. To investigate the effect of the specific α7nAChR agonist, PNU282987, on cardiac remodelling induced by isoproterenol (ISO 60 mg/kg per day) in mice, the cardiomyocyte cross-sectional area (CSA) and collagen volume fraction were evaluated by hematoxylin and eosin (HE) and Masson staining, respectively. Cardiac function and ventricular wall thickness were measured by echocardiography. The protein expressions of collagen I, matrix metalloproteinase 9 (MMP-9), transforming growth factor β1 (TGF-β1), and Smad3 were analyzed by Western blot. ISO-induced cardiac hypertrophy, characterized by an increase in the heart weight/body weight ratio, CSA and ventricular wall thickness. Moreover, cardiac fibrosis indices, such as collagen volume fraction, MMP-9 and collagen I protein expression, were also increased by ISO. PNU282987 not only attenuated cardiac hypertrophy but also decreased the cardiac fibrosis induced by ISO. Furthermore, PNU282987 suppressed TGF-β1 protein expression and the phosphorylation of Smad3 induced by ISO. In conclusion, PNU282987 ameliorated the cardiac remodelling induced by ISO, which may be related to the TGF-β1/Smad3 pathway. These data imply that the α7nAChR may represent a novel therapeutic target for cardiac remodelling in many cardiovascular diseases.

A new fabrication method to produce low residual stress PECVD SiNx layers at high frequency (13.56 MHz) was developed. High frequency up to 60W is employed in this new method to fabricate low stress SiNx. By adjusting the composition of reactant gases, process vacuum and the chamber temperature, the residual stress can be lower to-0.28 MPa, and high deposition rate up to 240 nm/min can be achieved. In addition, this paper investigated the influence of other important parameters on the results, such as pressure, power and gases flow rates. Moreover, by using the optimal process, the refractive index is ranged from 1.98 to 2.20, and the uniformity of run to run wafers is about ±3% for 4 inch wafers. Finally, a typical FBAR (film bulk acoustic wave resonator) structure using these low stress PECVD SiNx layers as solid layer and mask indicated that these layers are compatible in IC technology and suitable for using in fabricating MEMS(microelectromechanical systems) devices.

A micro piezoelectric cantilever beam array is designed for vibration energy harvesting. A single degree of freedom analytical model is developed to predict the properties of the device and is verified by finite element method. The piezoelectric material Aluminum Nitride was chosen for the compatibility with the CMOS process. The devices consisting of 5 piezoelectric cantilever beams and one proof mass were fabricated using micromachining technology. The resonance frequency, voltage and power were tested at excitation acceleration of 5.0 g. The maximum output power of the device is 9.13 μW at the resonance frequency of 1315 Hz when piezoelectric beams are connected in parallel.

This paper describes the fabrication and measurement results of piezoelectric energy harvester arrays based on aluminum nitride (AlN) as a piezoelectric material. The AlN piezoelectric thin film with crystal orientation (002) and crystal orientation (101) is deposited respectively by pulsed_DC sputtering on the different bottom electrode materials. Based on the AlN thin film, the piezoelectric vibration energy harvester arrays with 5 cantilever beams were developed. Then the load characteristics, frequency characteristics, harvester connected in series and parallel properties of harvester were investigated. In addition, we compare the properties of piezoelectric vibration energy harvester arrays with crystal orientation (101) and (002), where a record max power output of 0.23 μW and 0.38μW are obtained respectively when the value of acceleration was 1 g, while for the latter, the maximum power is 9.13 μW at the acceleration of 5.0g with the optimized resistance of 15 kΩ.

This paper focuses on the scale correction of coastline extracted from remote sensing images. Measurement of coastline is one of the basic and core work of coastal zone remote sensing monitoring projects. Based on analysis of coastline scale effect and multi-scale simulation of coastline, a scale correction method is presented for remote sensing coastline. This method can be used to correct remote sensing coastline to specified map scale, in order to obtain high-precision remote sensing monitoring results of coastline. The results of application example showed that the absolute error of coastline length is reduced to about one third of the original error after correction using the presented method. So the presented method can increase the accuracy of remote sensing coastline for specified scale substantially.

Periodontitis is a severe inflammatory response, leading to characteristic periodontal soft tissue destruction and alveolar bone resorption. Baicalin possesses potent anti-inflammatory activity; however, it is still unclear whether baicalin regulates toll-like receptor (TLR) 2/4 expression and downstream signaling during the process of periodontitis. In this study, the cervical area of the maxillary second molars of rats was ligated and inoculated with Porphyromonas gingivalis (P. gingivalis) for 4weeks to induce periodontitis. Some rats with periodontitis were treated intragastrically with baicalin (50, 100 or 200mg/kg/day) or vehicle for 4weeks. Compared with the sham group, the levels of TLR2, TLR4 and MyD88 expression and the p38 MAPK and NF-κB activation were up-regulated in the experimental periodontitis group (EPG), accompanied by marked alveolar bone loss and severe inflammation. Treatment with 100 or 200mg/kg/day baicalin dramatically reduced the alveolar bone loss, the levels of HMGB1, TNF-α, IL-1β, and MPO expression, and the numbers of inflammatory infiltrates in the gingival tissues. Importantly, treatment with 100 or 200mg/kg/day baicalin mitigated the periodontitis-up-regulated TLR2, TLR4 and MyD88 expression, and the p38 MAPK and NF-κB activation. Hence, the blockage of the TLR2 and TLR4/MyD88/p38 MAPK/NF-κB signaling by baicalin may contribute to its anti-inflammatory effects in rat model of periodontitis. In conclusion, these novel findings indicate that baicalin inhibits the TLR2 and TLR4 expression and the downstream signaling and mitigates inflammatory responses and the alveolar bone loss in rat experimental periodontitis. Therefore, baicalin may be a potential therapeutic agent for treatment of periodontitis.

The role of celecoxib in cardiovascular events remains contentious. The aim of the present study was to investigate the effects of celecoxib in acute myocardial ischaemia (AMI) in rabbits in comparison with those of another non-steroidal anti-inflammatory drug, namely aspirin. Male New Zealand white rabbits were divided into four groups: (i) a sham-operated group; (ii) an AMI group, in which the left anterior descending coronary arteries were occluded for 60 min; (iii) the celecoxib + AMI group, pretreated with 3 mg/kg celecoxib, twice a day, for 3 days before AMI induction; and (iv) the aspirin + AMI group, pretreated with 12.5 mg/kg aspirin, twice a day, for 3 days before AMI induction. Haemodynamic parameters were monitored using a multichannel physiological recorder. Serum levels of creatine kinase (CK), malondialdehyde (MDA), cyclo-oxygenase-2 (COX-2), tumour necrosis factor (TNF)-α, total nitrate/nitrite (NO(x) ), nitric oxide synthase (NOS) and myocardial infarct size were determined. Changes in isometric tension of isolated coronary rings were recorded by a myograph system. Compared with the sham group, the AMI group had lower blood pressure, higher left ventricular (LV) end-diastolic pressure, depressed maximum dP/dt of LV pressure, a larger infarct size and higher CK and MDA levels. Celecoxib, but not aspirin, pretreatment significantly ameliorated these effects of AMI. Celecoxib reversed AMI-induced increases in COX-2 levels to a similar extent as aspirin. Pretreatment with celecoxib resulted in a significant reduction in TNF-α levels and an increase in NO(x) and NOS levels compared with the AMI group. The dysfunctional vasoconstriction and vasodilation of coronary arteries were ameliorated by celecoxib administration. 4. In conclusion, the experimental evidence suggests that celecoxib exerts its protective effects in a COX-independent manner.

It is presented a fabrication processing of a two step method in deep silicon etching for MEMS applications using an the UK company Surface Technology Systems plc (STS), inductively-coupled plasma (ICP) etch technique STS ICP deep dry etching system. A brief introduction of schematic process of etching deep trenches on silicon substrate is first given, then with two step method for etching deep trenches. The film bulk acoustic resonator (FBAR) devices have been fabricated using STS ICP deep dry etching system with maximum etch rate of 4.6μ m/min, depth more than 450μm and sidewall roughness no more than 0.14μm. At the end of the second step process, the etch selective ratio of silicon to silicon oxygen is enhanced to ensure the device yield. At the same time, the negative effects such as microloads effects, footing effects, lag effects and micrograss effects are suppressed effectively.

It is known that the wet chemical etching of silicon in alkaline solution has attracted wide attention due to its advantages such as lower cost, simpler setup, higher rate, smoother surface at micro level, higher degree of anisotropy, and lower pollution. In this paper, the key processes of fabricating vacuum microelectronic accelerometer and slits are presented. The cone curvature radius of the silicon tip arrays less than 30nm was fabricated with wet anisotropic etching of silicon in 33wt. % KOH solution at 70°C added potassium iodine (KI) and Iodine (I2) as additive and the cone aspect ratio was about 0.7. Smooth surface after etching in 33wt. %KOH solution added isopropyl alcohol (IPA) at 80°C was obtained and lateral etching was less than 5um after etching several hours for etching depth over 400um. Scalar slits with bottom width 25um and depth 500um were attained. A constant etch rate lead to precise and reproducible production. The test result reveals that the process to a specific occasion can reach practical requirements.

This paper presents a simple but reliable fabrication process for microfluidic devices on glass substrate using wet etching technology. Instead of using expensive Pyrex glasses as substrates and depositing expensive metal or polysilicon/amorphous silicon as etch masks in conventional method, glass slide is used as substrate and a single-layer negative photoresist RFJ-220 is used as the etching mask. The etch rates, generation of defects, undercut ratio and surface roughness are studied. In order to achieve high etching depth and smooth surface, buffered oxide etching with hydrochloric acid as additive is proposed. By proper cleaning and long-time hard baking, the undercut ratio can approach to 1. An 110μm depth microchannel with smooth surface is achieved. This fabrication process leads to a considerable reduction of process steps, fabrication time and material consumption. With this technique, we successfully fabricated a microfluidic device, which is used in the capture of hepatoma cells HepG2.

1. Endothelial dysfunction plays a critical role in the development and progression or pathogenesis of hypertension. Amlodipine, a calcium channel blocker, is an effective antihypertensive agent. We investigated the effects of amlodipine on endothelial dysfunction in mesenteric arteries from spontaneously hypertensive rats (SHR). 2. Eight-week-old SHR were treated with amlodipine (10 mg/kg per day) for 8 weeks. Control SHR and Wistar-Kyoto (WKY) rats were treated with saline. Systolic blood pressure (SBP) was measured by the tail-cuff method. Isometric tension changes of isolated mesenteric arterial rings were recorded continuously by a myograph system. Serum contents of malondialdehyde (MDA) and total nitrate/nitrite (NO(x) ) were determined. Vascular superoxide anion production was analysed with dihydroethidium (DHE) fluorescence. 3. The contractile responses to KCl and phenylephrine were greater in untreated SHR than in WKY. Acetylcholine (ACh)-induced relaxation was significantly impaired in untreated SHR. Amlodipine treatment reduced the contractions and improved relaxation to ACh. In WKY, relaxation to ACh was inhibited by N(G) -nitro-l-arginine methyl ester (l-NAME) and not changed by ascorbic acid. In untreated SHR, the response to ACh was unaffected by l-NAME, whereas it was improved by ascorbic acid. Amlodipine restored the inhibitory effect of l-NAME on ACh-induced relaxation, but ascorbic acid no longer exerted its facilitating effect. Amlodipine prevented the rise in SBP and ameliorated abnormalities in serum MDA and NO in untreated SHR. DHE assay showed an increased intravascular superoxide generation in untreated SHR, which was abrogated by amlodipine. 4. Treatment of SHR with amlodipine resulted in amelioration of endothelial dysfunction by anti-oxidant activity and improvement in NO availability.

1. Cardiac acetylcholine receptors are involved in the negative inotropic effect of the vagus and the protection of the stimulated vagal nerve against myocardial ischaemic injury. Acetylcholine receptors consist of five types of muscarinic acetylcholine receptors (M AChR) and several nicotinic acetylcholine receptors (nAChR). Notably, ischaemic heart disease is accompanied by substantial withdrawal of vagal activity. However, it is not entirely clear what the changes of M(2,4) AChR and α7-nAChR expression are after cardiac ischaemia/reperfusion (I/R) injury. 2. Cardiac functions were continuously recorded in Langendorff mode during 30 min of ischaemia and 60 min of reperfusion. Lactate dehydrogenase (LDH) leakage was measured. M(2,4) AChRs and α7-nAChR expression were measured by reverse transcription polymerase chain reaction and western blot. 3. In hearts exposed to I/R injury, left ventricular development pressure, heart rate and ± dP/dt decreased significantly compared with the controls. LDH leakage increased with respect to the controls during reperfusion. 4. In normal hearts, expression of M(2,4) AChR in the left ventricle were lower than in atria and the right ventricle, whereas expression of α7-nAChR was dramatically higher in the left ventricle and right ventricle than the atria. After reperfusion, the mRNA and protein expression of M(2) AChR increased notably in the left and right ventricle, and α7-nAChR was enhanced significantly in the left ventricle. M(4) AChR mRNA expression reduced notably after ischaemia and recovered to the control level after reperfusion in the atria, but the protein level did not change. 5. In conclusion, the increase in M(2) AChR and α7-nAChR after reperfusion might be the compensatory response to myocardial I/R injury, providing new information for treatment of myocardial I/R injury.

Apoptosis of cardiomyocytes plays an important role in the development of cardiovascular diseases (CVD). Numerous studies have shown that generation of reactive oxygen species (ROS) induced by the renin-angiotensin system (RAS) is involved in this pathological process. Recent studies also suggested that acetylcholine (ACh) prevented the hypoxia-induced apoptosis of mouse ES cells by inhibiting the ROS production. However, whether ACh can inhibit the action of angiotensin II (Ang II) and subsequently prevent CVD development remains unclear. In this study, H9c2 cells were stimulated by 10(-6) M Ang II for 24 h with or without 10(-5) M ACh, 10(-5) M ACh + 10(-4) M atropine respectively. The results demonstrated that Ang II increased apoptosis index by fourfold (vs. the control group, P 0.01), which were significantly diminished by ACh. However, the atropine (ACh receptor [AChR] inhibitor) treatment blocked the protective effect of ACh. Subsequently, Ang II significantly increases the expression and activity of NADPH oxidase so that ROS production is increased by sevenfold (vs. control group, P 0.01). The activity and expression of caspase-3 along with the Bax/Bcl2 ratio and the levels of p38 mitogen activated protein kinase (MAPK) phosphorylation also appeared to follow a similar trend. Furthermore, we observed that ACh could reduce up-regulation of AT1 receptor expression induced by Ang II. However, all these effects of ACh were inhibited by atropine. In conclusion, ACh prevents Ang II-induced H9c2 cells apoptosis through down-regulation of the AT1 receptor and inhibition of ROS-mediated p38 MAPK activation as well as regulation of Bcl-2, Bax and caspase-3.