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951.
Assessment of potential allergenicity and patterns of cross-reactivity is necessary whenever novel proteins are introduced into human food chain. Current bioinformatic methods in allergology focus mainly on the prediction of allergenic proteins, with no information on cross-reactivity patterns among known allergens. In this study, we present AllerTool, a web server with essential tools for the assessment of predicted as well as published cross-reactivity patterns of allergens. The analysis tools include graphical representation of allergen cross-reactivity information; a local sequence comparison tool that displays information of known cross-reactive allergens; a sequence similarity search tool for assessment of cross-reactivity in accordance to FAO/WHO Codex alimentarius guidelines; and a method based on support vector machine (SVM). A 10-fold cross-validation results showed that the area under the receiver operating curve (A(ROC)) of SVM models is 0.90 with 86.00% sensitivity (SE) at specificity (SP) of 86.00%. Availability: AllerTool is freely available at http://research.i2r.a-star.edu.sg/AllerTool/.  相似文献   
952.
For the first time, lipozyme TL IM, an inexpensive lipase from Thermomyces lanuginosa, was successfully applied to the regioselective synthesis of lipophilic 5-fluorouridine ester derivatives. The ESI-MS and (13)C NMR analysis confirmed that the end products of the acylation were 5'-O-acyl 5-fluorouridines, more powerful anti-tumor drugs than 5-fluorouridine itself. Notably, the chain length of acyl donors had an obvious effect on the initial rate and the maximum substrate conversion of the regioselective acylation. The acylation of 5-fluorouridine with vinyl laurate was used as a model to explore the influence of various factors on the reaction with respect to the initial rate, the maximum substrate conversion and the regioselectivity. The optimum water activity, the molar ratio of vinyl laurate to 5-fluorouridine, reaction temperature and shaking rate were 0.07, 15/1, 45 degrees C and 200rpm, respectively, under which the maximum substrate conversion and the regioselectivity were as high as 98.4 and >99%, respectively, after a reaction time of around 6h.  相似文献   
953.
A recombinant mouse interleukin-4 (IL-4) and three different purified rat antimouse IL-4 monoclonal antibodies (Mab) with different clonalities were employed as a model system. This system was used to examine monoclonal antibody effectiveness using both conventional and high-throughput measurement techniques to select antibodies for attaining the most sensitive detection of the recombinant IL-4 through the "sandwich-type" immunoassays. Surface plasmon resonance (SPR) measurements and two high-throughput methods, suspension arrays (also called multiplexed bead arrays) and forward-phase protein microarrays, predicted the same capture (BVD4-1D11) and detection (BVD6-24G2) antibody pair for the most sensitive detection of the recombinant cytokine. By using this antibody pair, we were able to detect as low as 2 pg/mL of IL-4 in buffer solution and 13.5 pg/mL of IL-4 spiked in 100% normal mouse serum with the multiplexed bead arrays. Due to the large amount of material required for SPR measurements, the study suggests that the multiplexed bead arrays and protein microarrays are both suited for the selection of numerous antibodies against the same analyte of interest to meet the need in the areas of systems biology and reproducible clinical diagnostics for better patient care.  相似文献   
954.
Chen  Siyu  Zeng  Xiangchang  Zong  Wenjing  Wang  Xintong  Chen  Lulu  Zhou  Luping  Li  Chaopeng  Huang  Qi  Huang  Xinyi  Zeng  Guirong  Hu  Kai  Ouyang  Dong-Sheng 《Neurochemical research》2019,44(2):472-484

Neuroinflammation and imbalance of neurotransmitters play pivotal roles in seizures and epileptogenesis. Aucubin (AU) is an iridoid glycoside derived from Eucommia ulmoides that possesses anti-inflammatory and neuroprotective effects. However, the anti-seizure effects of AU have not been reported so far. The present study was designed to investigate the effects of AU on pilocarpine (PILO) induced seizures and its role in the regulation of neuroinflammation and neurotransmission. We found that AU reduced seizure intensity and prolonged the latency of seizures. AU significantly attenuated the activation of astrocytes and microglia and reduced the levels of interleukine-1 beta (IL-1β), high mobility group box 1 (HMGB1), tumor necrosis factor-α (TNF-α). Furthermore, the contents of γ-aminobutyric acid (GABA) were increased while the levels of glutamate were decreased in the hippocampus with AU treatment. The expression of γ-aminobutyric acid type A receptor subunit α1 (GABAARα1) and glutamate transporter-1 (GLT-1) protein were up-regulated in AU treatment group. However, AU had no significant effect on N-methyl-d-aspartate receptor subunit 2B (NR2B) expression in status epilepticus (SE). In conclusion, our findings provide the first evidence that AU can exert anti-seizure effects by attenuating gliosis and regulating neurotransmission. The results suggest that AU may be developed as a drug candidate for the treatment of epilepsy.

  相似文献   
955.
Spinal cord injury (SCI) is a public health problem in the world. The SCI usually triggers an excessive inflammatory response that brings about a secondary tissue wreck leading to further cellular and organ dysfunction. Hence, there is great potential of reducing inflammation for therapeutic strategies of SCI. In this study, we aim to investigate if Salidroside (SAD) exerts an anti-inflammatory effect and promotes recovery of motor function on SCI through suppressing nuclear factor-κB (NF-κB) and the mitogen-activated protein kinase (MAPK) pathways. In vitro, real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) were used to examine the inhibitory effect of SAD on the expression and release of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) activated by lipopolysaccharide (LPS) in astrocytes. In addition, SAD was found to inhibit NF-κB, p38 and extracellular-regulated protein kinases (ERK) signaling pathways by western blot analysis. Further, in vivo study showed that SAD was able to improve hind limb motor function and reduce tissue damage accompanied by the suppressed expression of inflammatory cytokines IL-1β, IL-6, and TNF-α. Overall, SAD could reduce the inflammatory response and promote motor function recovery in rats after SCI by inhibiting NF-κB, p38, and ERK signaling pathways.  相似文献   
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957.
958.

Background

Arenaviruses are a family of rodent-borne viruses that cause several hemorrhagic fevers. These diseases can be devastating and are often lethal. Herein, to aid in the design and development of diagnostics, treatments and vaccines for arenavirus infections, we have developed a database containing protein sequences from the seven pathogenic arenaviruses (Junin, Guanarito, Sabia, Machupo, Whitewater Arroyo, Lassa and LCMV).

Results

The database currently contains a non-redundant set of 333 protein sequences which were manually annotated. All entries were linked to NCBI and cited PubMed references. The database has a convenient query interface including BLAST search. Sequence variability analyses were also performed and the results are hosted in the database.

Conclusion

The database is available at http://epitope.liai.org:8080/projects/arena and can be used to aid in studies that require proteomic information from pathogenic arenaviruses.  相似文献   
959.
Lin Y  Tang YJ  Zong HL  Gu JX  Deng WW  Wang C  Sun B 《FEBS letters》2007,581(26):5151-5157
Interleukin 12 receptor beta1 (IL-12Rbeta1) and beta2 (IL-12Rbeta2) constitute the functional and high-affinity receptor complex for interleukin 12 (IL-12) and mediate important functions in activated T cells. In this study, we identified cyclin G associated kinase (GAK) as a new IL-12Rbeta2-interacting protein using yeast two-hybrid system and confirmed it by coimmunoprecipitation assays. Overexpression of GAK in activated T cells suppresses IL-12 induced IFN-gamma production but has no detectable effects on its proliferation, whereas knockdown of GAK by RNA interference (RNAi) increases IFN-gamma production. These results suggest that GAK associates with IL-12Rbeta2 and may play a role in regulating IL-12 signaling.  相似文献   
960.
冠心病是由多种病理因素引起的复杂疾病,严重威胁人类健康,其机制尚未完全阐明。近年来,研究表明冠心病与口腔和肠道菌群密切相关。菌群失调导致的炎症反应、氧化应激反应、脂质代谢失调和氧化三甲胺累积是参与冠心病发生的主要风险因素。此外,口腔菌群与肠道菌群相关,参与冠心病的发生与发展。中医治疗疾病的优势在于辨证论治,而证型的判断缺乏客观标准。多项研究应用口腔菌群或肠道菌群分析了疾病的中医证型。本文系统地阐述了口腔菌群和肠道菌群在冠心病发病机制中的作用,阐述了不同中医证型冠心病菌群分析的研究进展,为临床开展此类研究提供参考。  相似文献   
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