88 research outputs found
House dust mite trapping kit
Examination of dust collected from the homes of asthmatic patients showed there were significant numbers of house dust mites (HDM). The allergens generated from HDM are considered to be among the risk factors for asthma development. HDM can be identified in mattresses, carpets, quilts and pillows. HDM are about 0.2 x 0.3 mm in size, so they are only clearly visible under microscopic magnification. Therefore, it is important to develop a trapping kit to capture and stain them. We devised a trapping kit that is comprised of an adhesive pad and a staining agent. The adhesive pad is made of cotton cloth and is coated with glue, which can attract and trap HDM to prevent them from further spreading. The staining agent contains nanogold-coupled monoclone antibodies, which can react with HDM through binding with group 2 allergens on the body surface of HDM. After staining, both Dermatophagoides pteronyssinus (Dp) and Tyrophagus putrescentiae (Tp) become visible to the naked eye.Our study showed that the HDM trapping pad can attract and trap HDM. The stainingagent makes them visible so they can be counted. This kit can help us to identify the predominant HDM infestation area in the household environment. By identifying the infestation area, we can reduce HDM exposure and prevent the development of allergic disease
Probiotic actions on diseases: implications for therapeutic treatments
The ecology of gut microflora, which colonizes all body surfaces, has long coevolved with its hosts in a complicated fashion. Health benefits conferred by gut microflora include defense against invading pathogens, improvement of nutritional bioavailability, and development of the regional and systemic immune systems. The past decade has witnessed growing interest in the fact that the gut microflora affects the host's energy homeostasis by means of various mechanisms, including supplying nourishment from indigestible compounds, producing small biomolecules responsible for lipid profiles, and participating in the absorption, distribution, metabolism and excretion of nutrition. Much in vitro and in vivo research has indicated that aberrant gut microflora plays an important role in the pathogenesis of a wide spectrum of diseases. This is accomplished by a shift in focus, from laying an emphasis on pharmacotherapy to placing more effort on gut microflora normalization. The objectives of this review include illustrating trends in the clinical application of probiotics on diseases, as well as discussing current methodology limitations on probiotic selection. Furthermore, it is expected to shed light on the nature of probiotics, with the aim of giving greater insight into the implications for clinical use of probiotics in the treatment of diseases
Electrochemical impedimetric biosensor based on a nanostructured polycarbonate substrate
This study integrates the techniques of nanoelectroforming, hot-embossing, and electrochemical deposition to develop a disposable, low-cost, and high sensitivity nanostructure biosensor. A modified anodic aluminum oxide barrier-layer surface was used as the template for thin nickel film deposition. After etching the anodic aluminum oxide template off, a three-dimensional mold of the concave nanostructure array was created. The fabricated three-dimensional nickel mold was further used for replica molding of a nanostructure polycarbonate substrate by hot-embossing. A thin gold film was then sputtered onto the polycarbonate substrate to form the electrode, followed by deposition of an orderly and uniform gold nanoparticle layer on the three-dimensional gold electrode using electrochemical deposition. Finally, silver nanoparticles were deposited on the uniformly deposited gold nanoparticles to enhance the conductivity of the sensor. Electrochemical impedance spectroscopy analysis was then used to detect the concentration of the target element. The sensitivity of the proposed scheme on the detection of the dust mite antigen, Der p2, reached 0.1 pg/mL
TNF-α Mediates Eosinophil Cationic Protein-induced Apoptosis in BEAS-2B Cells
<p>Abstract</p> <p>Background</p> <p>Eosinophilic granulocytes are important for the human immune system. Many cationic proteins with cytotoxic activities, such as eosinophil cationic protein (ECP) and eosinophil-derived neurotoxin (EDN), are released from activated eosinophils. ECP, with low RNase activity, is widely used as a biomarker for asthma. ECP inhibits cell viability and induces apoptosis to cells. However, the specific pathway underlying the mechanisms of ECP-induced cytotoxicity remains unclear. This study investigated ECP-induced apoptosis in bronchial epithelial BEAS-2B cells and elucidated the specific pathway during apoptosis.</p> <p>Results</p> <p>To address the mechanisms involved in ECP-induced apoptosis in human BEAS-2B cells, investigation was carried out using chromatin condensation, cleavage of poly (ADP-ribose) polymerase (PARP), sub-G1 distribution in cell cycle, annexin V labeling, and general or specific caspase inhibitors. Caspase-8-dependent apoptosis was demonstrated by cleavage of caspase-8 after recombinant ECP treatment, accompanied with elevated level of tumor necrosis factor alpha (TNF-α). Moreover, ECP-induced apoptosis was effectively inhibited in the presence of neutralizing anti-TNF-α antibody.</p> <p>Conclusion</p> <p>In conclusion, our results have demonstrated that ECP increased TNF-α production in BEAS-2B cells and triggered apoptosis by caspase-8 activation through mitochondria-independent pathway.</p
Mite Allergen Der-P2 Triggers Human B Lymphocyte Activation and Toll-Like Receptor-4 Induction
Background: Allergic disease can be characterized as manifestations of an exaggerated inflammatory response to environmental allergens triggers. Mite allergen Der-p2 is one of the major allergens of the house dust mite, which contributes to TLR4 expression and function in B cells in allergic patients. However, the precise mechanisms of Der-p2 on B cells remain obscure. Methodology/Principal Findings: We investigated the effects of Der-p2 on proinflammatory cytokines responses and Toll-like receptor-4 ( TLR4)-related signaling in human B cells activation. We demonstrated that Der-p2 activates proinflammatory cytokines, TLR4 and its co- receptor MD2. ERK inhibitor PD98059 significantly enhanced TLR4/MD2 expression in Der-p 2-treated B cells. Der-p2 markedly activated mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1) and decreased p38 phosphorylation in B cells. MKP-1-siRNA downregulated TLR4/MD2 expression in Der -p2-treated B cells. In addition, Der-p2 significantly up- regulated expression of co- stimulatory molecules and increased B cell proliferation. Neutralizing Der -p2 antibody could effectively abrogate the Der-p2-induced B cell proliferation. Der-p2 could also markedly induce NF-kappa B activation in B cells, which could be counteracted by dexamethasone. Conclusions/ Significance: These results strongly suggest that Der-p2 is capable of triggering B cell activation and MKP-1-activated p38/MAPK dephosphorylation- regulated TLR4 induction, which subsequently enhances host immune, defense responses and development of effective allergic disease therapeutics in B cells
Lactobacillus casei MYL01 modulates the proinflammatory state induced by ethanol in an in vitro model
Accumulating studies have suggested that probiotics have beneficial effects on liver injury but the underlying mechanism has remained unclear. Toll-like receptors (TLR) expressed on immune cells and hepatocytes recognize bacterial components that are translocated from the gut into the portal vein. To date, it has been demonstrated that ethanol alone, without microbial components, is able to activate TLR, leading to promotion of proinflammatory cytokine production. Because the enhanced signaling of TLR triggers persistent inflammation, we hypothesized that development of hepatocyte TLR tolerance to repetitive stimulation plays an important role in protecting the liver from hypergeneration of proinflammatory cytokines. In this study, we showed that Lactobacillus casei MYL01 modulated the proinflammatory state induced by ethanol and investigated in detail the mechanism underlying the observation that L. casei MYL01 gave rise to TLR tolerance toward ethanol stimulation. The effects of L. casei MYL01 in the attenuation of ethanol-induced liver damage were due to enhancement of IL-10 production, which limited the proinflammatory process. Furthermore, better defense of hepatocytes against ethanol challenge by treatment of L. casei MYL01 was attributed to previous induction of toll interacting protein (TOLLIP) and suppressor of cytokine signaling (SOCS)1 and SOCS3 expression via activation of TLR1, TLR2, TLR6, and TLR9, an action that cross-regulated ethanol-TLR4-nuclear factor κB signal transduction events. This finding might help establish an in vitro platform for selecting hepatoprotective probiotic strains in terms of ethanol-induced liver damage
A Disease Marker for Aspirin-Induced Chronic Urticaria
There are currently no diagnostic methods in vitro for aspirin-induced chronic urticaria (AICU) except for the provocation test in vivo. To identify disease markers for AICU, we investigated the single nucleotide polymorphism (SNP) of the promoter loci of high-affinity IgE receptor (FcεRIα) and CD203c expression level in Chinese patients with AICU. We studied two genotypic and allelic frequencies of rs2427827 (–344C/T) and rs2251746 (–66T/C) gene polymorphisms of FcεRIα in 20 patients with AICU, 52 subjects with airway hypersensitivity without aspirin intolerance, and 50 controls in a Chinese population. The results showed that the frequencies of two SNPs (–344C>T, –66C>T) were similar to the normal controls. The allele frequency of –344CC was significantly higher in the patients with AICU compared to those with airway sensitivity (p = 0.019). We also studied both histamine release and CD203c expression on KU812 cells to assess aspirin-induced basophil activation. We found that the activity of basophil activation of AICU was significantly higher in the patients with AICU compared to those with airway hypersensitivity without aspirin intolerance. The mean fluorescence intensity of the CD203c expression were 122.5 ± 5.2 vs. 103.3 ± 3.3 respectively, (p < 0.05), and the percentages of histamine release were 31.3% ± 7.4% vs. −24.0% ± 17.5%, (p < 0.05) respectively. Although the mean fluorescence intensity of CD203c expression and the percentage of histamine release were significantly up-regulated by aspirin, they were not affected by anti-IgE antibodies. These results suggest that a single SNP of FcεRIα (–344C>T) is less likely to develop AICU and the basophil activation activity in the sera by measuring CD203c expression can be applicable to confirm the diagnosis of AICU
Heat-Killed Lactic Acid Bacteria Enhance Immunomodulatory Potential by Skewing the Immune Response toward Th1 Polarization
Heat-killed lactic acid bacteria not only possess immunomodulatory functions but also provide the advantages of longer product shelf life, easier storage, and more convenient transportation. To establish appropriate heat treatments for the industrial preparation of probiotics with immunomodulatory effects, 4 different heat treatments were used to kill 11 strains of lactic acid bacteria. Comparisons among the strains and with viable forms were carried out in terms of immunomodulatory activity and adhesion to Caco-2 cells. Field-emission scanning electron microscope (FE-SEM) was employed to observe morphological changes in bacteria after heating. Among the 11 viable strains, Lactobacillus gasseri AI-88 was the strongest inducer of interferon-gamma (IFN)-gamma and interleukin (IL)-12p70 production. However, after heat treatments its stimulatory ability was attenuated. Heat-killed Enterococcus faecalis YM-73 and Lactobacillus salivarius AP-32 strains showed enhanced stimulation of IFN-gamma and IL-12p70 secretion and coincidental decrease in IL-13 production. The adhesion of lactic acid bacteria to Caco-2 cells decreased with increases in temperature. However, heat exposure did not influence immunomodulatory activity. With rising temperature, roughness and unevenness of bacterial cell surfaces increased significantly. The results indicated that heat-killed E. faecalis YM-73 and L. salivarius AP-32 have immunomodulatory ability via increased Th1-associated cytokines and reduced Th2-associated cytokines, switching the immune response from a Th2 toward a Th1 response. These 2 heat-killed strains have the potential for development as commercial products
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