Lactobacillus acidophilus ameliorates H. pylori-induced gastric inflammation by inactivating the Smad7 and NFκB pathways

<p>Abstract</p> <p>Background</p> <p><it>H. pylori </it>infection may trigger Smad7 and NFκB expression in the stomach, whereas probiotics promote gastrointestinal health and improve intestinal inflammation caused by pathogens. This study examines if probiotics can improve <it>H. pylori</it>-induced gastric inflammation by inactivating the Smad7 and NFκB pathways.</p> <p>Results</p> <p>Challenge with <it>H. pylori </it>increased IL-8 and TNF-α expressions but not TGF-β1 in MKN45 cells. The RNA levels of Smad7 in AGS cells increased after <it>H. pylori </it>infection in a dose-dependent manner. A higher dose (MOI 100) of <it>L. acidophilus </it>pre-treatment attenuated the <it>H. pylori</it>-induced IL-8 expressions, but not TGF-β1. Such anti-inflammatory effect was mediated via increased cytoplasmic IκBα and depletion of nuclear NFκB. <it>L. acidophilus </it>also inhibited <it>H. pylori</it>-induced Smad7 transcription by inactivating the Jak1 and Stat1 pathways, which might activate the TGF-β1/Smad pathway. <it>L. acidophilus </it>pre-treatment ameliorated IFN-γ-induced Smad7 translation level and subsequently reduced nuclear NF-κB production, as detected by western blotting.</p> <p>Conclusions</p> <p><it>H. pylori </it>infection induces Smad7, NFκB, IL-8, and TNF-α production <it>in vitro</it>. Higher doses of <it>L. acidophilus </it>pre-treatment reduce <it>H. pylori</it>-induced inflammation through the inactivation of the Smad7 and NFκB pathways.</p

System-Level Biochip for Impedance Sensing and Programmable Manipulation of Bladder Cancer Cells

This paper develops a dielectrophoretic (DEP) chip with multi-layer electrodes and a micro-cavity array for programmable manipulations of cells and impedance measurement. The DEP chip consists of an ITO top electrode, flow chamber, middle electrode on an SU-8 surface, micro-cavity arrays of SU-8 and distributed electrodes at the bottom of the micro-cavity. Impedance sensing of single cells could be performed as follows: firstly, cells were trapped in a micro-cavity array by negative DEP force provided by top and middle electrodes; then, the impedance measurement for discrimination of different stage of bladder cancer cells was accomplished by the middle and bottom electrodes. After impedance sensing, the individual releasing of trapped cells was achieved by negative DEP force using the top and bottom electrodes in order to collect the identified cells once more. Both cell manipulations and impedance measurement had been integrated within a system controlled by a PC-based LabVIEW program. In the experiments, two different stages of bladder cancer cell lines (grade III: T24 and grade II: TSGH8301) were utilized for the demonstration of programmable manipulation and impedance sensing; as the results show, the lower-grade bladder cancer cells (TSGH8301) possess higher impedance than the higher-grade ones (T24). In general, the multi-step manipulations of cells can be easily programmed by controlling the electrical signal in our design, which provides an excellent platform technology for lab-on-a-chip (LOC) or a micro-total-analysis-system (Micro TAS)

Aorta Fluorescence Imaging by Using Confocal Microscopy

The activated leukocyte attacked the vascular endothelium and the associated increase in VEcadherin number was observed in experiments. The confocal microscopic system with a prism-based wavelength filter was used for multiwavelength fluorescence measurement. Multiwavelength fluorescence imaging based on the VEcadherin within the aorta segment of a rat was achieved. The confocal microscopic system capable of fluorescence detection of cardiovascular tissue is a useful tool for measuring the biological properties in clinical applications

Interactions between Amyloid-β and Hemoglobin: Implications for Amyloid Plaque Formation in Alzheimer's Disease

Accumulation of amyloid-β (Aβ) peptides in the brain is one of the central pathogenic events in Alzheimer's disease (AD). However, why and how Aβ aggregates within the brain of AD patients remains elusive. Previously, we demonstrated hemoglobin (Hb) binds to Aβ and co-localizes with the plaque and vascular amyloid deposits in post-mortem AD brains. In this study, we further characterize the interactions between Hb and Aβ in vitro and in vivo and report the following observations: 1) the binding of Hb to Aβ required iron-containing heme; 2) other heme-containing proteins, such as myoglobin and cytochrome C, also bound to Aβ; 3) hemin-induced cytotoxicity was reduced in neuroblastoma cells by low levels of Aβ; 4) Hb was detected in neurons and glial cells of post-mortem AD brains and was up-regulated in aging and APP/PS1 transgenic mice; 5) microinjection of human Hb into the dorsal hippocampi of the APP/PS1 transgenic mice induced the formation of an envelope-like structure composed of Aβ surrounding the Hb droplets. Our results reveal an enhanced endogenous expression of Hb in aging brain cells, probably serving as a compensatory mechanism against hypoxia. In addition, Aβ binds to Hb and other hemoproteins via the iron-containing heme moiety, thereby reducing Hb/heme/iron-induced cytotoxicity. As some of the brain Hb could be derived from the peripheral circulation due to a compromised blood-brain barrier frequently observed in aged and AD brains, our work also suggests the genesis of some plaques may be a consequence of sustained amyloid accretion at sites of vascular injury

Traffic agents for improving QoS in mixed infrastructure and ad hoc modes wireless LAN

As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET) are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS) requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN), which can offer high data-rate wireless multimedia services to the mobile stations (MSs) in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP) and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs) to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth) of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light

Intramuscular electroporation with the pro-opiomelanocortin gene in rat adjuvant arthritis

Endogenous opioid peptides have an essential role in the intrinsic modulation and control of inflammatory pain, which could be therapeutically useful. In this study, we established a muscular electroporation method for the gene transfer of pro-opiomelanocortin (POMC) in vivo and investigated its effect on inflammatory pain in a rat model of rheumatoid arthritis. The gene encoding human POMC was inserted into a modified pCMV plasmid, and 0–200 μg of the plasmid-POMC DNA construct was transferred into the tibialis anterior muscle of rats treated with complete Freund's adjuvant (CFA) with or without POMC gene transfer by the electroporation method. The safety and efficiency of the gene transfer was assessed with the following parameters: thermal hyperalgesia, serum adrenocorticotropic hormone (ACTH) and endorphin levels, paw swelling and muscle endorphin levels at 1, 2 and 3 weeks after electroporation. Serum ACTH and endorphin levels of the group into which the gene encoding POMC had been transferred were increased to about 13–14-fold those of the normal control. These levels peaked 1 week after electroporation and significantly decreased 2 weeks after electroporation. Rats that had received the gene encoding POMC had less thermal hypersensitivity and paw swelling than the non-gene-transferred group at days 3, 5 and 7 after injection with CFA. Our promising results showed that transfer of the gene encoding POMC by electroporation is a new and effective method for its expression in vivo, and the analgesic effects of POMC cDNA with electroporation in a rat model of rheumatoid arthritis are reversed by naloxone

Observation of Majorana fermions with spin selective Andreev reflection in the vortex of topological superconductor

Majorana fermion (MF) whose antiparticle is itself has been predicted in condensed matter systems. Signatures of the MFs have been reported as zero energy modes in various systems. More definitive evidences are highly desired to verify the existence of the MF. Very recently, theory has predicted MFs to induce spin selective Andreev reflection (SSAR), a novel magnetic property which can be used to detect the MFs. Here we report the first observation of the SSAR from MFs inside vortices in Bi2Te3/NbSe2 hetero-structure, in which topological superconductivity was previously established. By using spin-polarized scanning tunneling microscopy/spectroscopy (STM/STS), we show that the zero-bias peak of the tunneling differential conductance at the vortex center is substantially higher when the tip polarization and the external magnetic field are parallel than anti-parallel to each other. Such strong spin dependence of the tunneling is absent away from the vortex center, or in a conventional superconductor. The observed spin dependent tunneling effect is a direct evidence for the SSAR from MFs, fully consistent with theoretical analyses. Our work provides definitive evidences of MFs and will stimulate the MFs research on their novel physical properties, hence a step towards their statistics and application in quantum computing.Comment: 4 figures 15 page