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81.
82.
Chlamydia trachomatis causes the most common sexually transmitted bacterial infection and trachoma, an eye infection. Untreated infections can lead to sequelae, such as infertility and ectopic pregnancy in women and blindness. We previously enhanced the antichlamydial activity of the fluoroquinolone ciprofloxacin by grafting a metal chelating moiety onto it. In the present study, we pursued this pharmacomodulation and obtained nanomolar active molecules (EC50) against this pathogen. This gain in activity prompted us to evaluate the antibacterial activity of this family of molecules against other pathogenic bacteria, such as Neisseria gonorrhoeae and bacteria from the ESKAPE group. The results show that the novel molecules have selectively improved activity against C. trachomatis and demonstrate how the antichlamydial effect of fluoroquinolones can be enhanced.  相似文献   
83.
对在分散控制系统中常见的操作站与分散过程控制站、分散过程控制站间和操作站间通讯系统的软件设计和组态等问题进行了讨论,它将对设计人员和用户对分散控制系统中通讯系统的设计和使用有一定的帮助。  相似文献   
84.
The use of nitrilotriacetic acid end‐functionalized polystyrenes (NTA‐PS) as a multifunctional nanocarrier for the aqueous dispersion of CdSe, γ‐Fe2O3 and gold nanoparticles (NPs) is described. When the amphiphilic end‐ functionalized polystyrenes and NPs are dissolved together in tetrahydrofuran, the addition of water causes the spontaneous formation of micellar aggregates, resulting in the successful encapsulation and aqueous dispersion of NPs. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), photoluminescence (PL) spectroscopy, and vibrating sample magnetometer (VSM) are used to characterize the structure and properties of the NPs‐containing micellar aggregates (nanocarrier). After complexation of Ni2+ with NTA on the surface of the nanocarrier containing γ‐Fe2O3, specific binding between Ni‐NTA complex and histidine‐tagged (His‐tagged) proteins enables selective separation of His‐tagged proteins using a magnet.  相似文献   
85.
Chemoradiation-induced mucositis is a debilitating condition of the gastrointestinal tract eventuating from antineoplastic treatment. It is believed to occur primarily due to oxidative stress mechanisms, which generate Reactive Oxygen Species (ROS). The aim of this scoping review was to assess the role of oxidative stress in the development of Oral Mucositis (OM). Studies from the literature, published in MEDLINE and SCOPUS, that evaluated the oxidative stress pathways or antioxidant interventions for OM, were retrieved to elucidate the current understanding of their relationship. Studies failing inclusion criteria were excluded, and those suitable underwent data extraction, using a predefined data extraction table. Eighty-nine articles fulfilled criteria, and these were sub-stratified into models of study (in vitro, in vivo, or clinical) for evaluation. Thirty-five clinical studies evaluated antioxidant interventions on OM’s severity, duration, and pain, amongst other attributes. A number of clinical studies sought to elucidate the protective or therapeutic effects of compounds that had been pre-determined to have antioxidant properties, without directly assessing oxidative stress parameters (these were deemed “indirect evidence”). Forty-seven in vivo studies assessed the capacity of various compounds to prevent OM. Findings were mostly consistent, reporting reduced OM severity associated with a reduction in ROS, malondialdehyde (MDA), myeloperoxidase (MPO), but higher glutathione (GSH) and superoxide dismutase (SOD) activity or expression. Twenty-one in vitro studies assessed potential OM therapeutic interventions. The majority demonstrated successful a reduction in ROS, and in select studies, secondary molecules were assessed to identify the mechanism. In summary, this review highlighted numerous oxidative stress pathways involved in OM pathogenesis, which may inform the development of novel therapeutic targets.  相似文献   
86.
Metalloendopeptidase ADAM-Like Decysin 1 (ADAMDEC1) is an anti-inflammatory peptidase that is almost exclusively expressed in the gastrointestinal (GI) tract. We have recently found abundant and selective expression of Adamdec1 in colonic mucosal PDGFRα+ cells. However, the cellular origin for this gene expression is controversial as it is also known to be expressed in intestinal macrophages. We found that Adamdec1 mRNAs were selectively expressed in colonic mucosal subepithelial PDGFRα+ cells. ADAMDEC1 protein was mainly released from PDGFRα+ cells and accumulated in the mucosal layer lamina propria space near the epithelial basement membrane. PDGFRα+ cells significantly overexpressed Adamdec1 mRNAs and protein in DSS-induced colitis mice. Adamdec1 was predominantly expressed in CD45 PDGFRα+ cells in DSS-induced colitis mice, with only minimal expression in CD45+ CD64+ macrophages. Additionally, overexpression of both ADAMDEC1 mRNA and protein was consistently observed in PDGFRα+ cells, but not in CD64+ macrophages found in human colonic mucosal tissue affected by Crohn’s disease. In summary, PDGFRα+ cells selectively express ADAMDEC1, which is localized to the colon mucosa layer. ADAMDEC1 expression significantly increases in DSS-induced colitis affected mice and Crohn’s disease affected human tissue, suggesting that this gene can serve as a diagnostic and/or therapeutic target for intestinal inflammation and Crohn’s disease.  相似文献   
87.
Journal of Mechanical Science and Technology - The cooling effect of oil cooling method on electric vehicle motors with hairpin winding is analyzed. A 160 kW motor being developed by a commercial...  相似文献   
88.
In this paper, we present a robust image processing algorithm for the automatic manipulation of tie rod in the automotive assembly process. A sensing system consisting of a camera and a slit laser is used to obtain 3D data for processing. It is attached to the robot’s arm. A nut runner is used as an end-effector of the robot to manipulate the bolt and nut on the tie rod. For the successful operation, a robust image processing algorithm that can cope with diverse illumination variations in manufacturing conditions is required. We present a robust algorithm for the extraction of laser contours on images. It consists of two steps where color and grey information is used to cope with clutters caused by laser reflections on metal surfaces. Experimental results using many images under real conditions show the robustness of the proposed algorithm.  相似文献   
89.
Molybdenum dioxide (MoO2) is a transition metal oxide with unusual metal-like electrical conductivity and high catalytic activity toward reforming hydrocarbons. This review covers the synthesis techniques used to fabricate MoO2 in a variety of morphologies and particle sizes. Processing from molybdenum ore and reduction from MoO3 are also covered, with emphasis on reduction mechanisms and kinetic considerations. Discussions of various solution-based and gas phase synthesis techniques shed light on strategies to achieve various unique morphologies, which leads into a brief discussion of nanoscale MoO2. Nanoscale MoO2 is of interest for important technological applications including catalysts for partial oxidation of hydrocarbons, solid oxide fuel cell anodes, and high-capacity reversible lithium ion battery anodes.  相似文献   
90.
The aim of this study was to prepare sunitinib-loaded biodegradable films using poly(l-lactide-co-?-caprolactone) (PLCL) for anti-tumor drug delivery. Sunitinib-loaded PLCL film has a rough surface, while empty film has a smooth surface. PLCL film loaded with 5% (w/w) sunitinib showed an absence of a crystalline peak of sunitinib, while sharp peaks were observed at 10% (w/w) loading, indicating that sunitinib was molecularly distributed in the polymer matrix at 5% (w/w). A drug release study revealed an initial burst during the first 2 h, followed by continuous release until 24 h. Since weight loss of film was <10% for 1 week, drug release mechanism was dominantly dependent on the diffusion-mediated release of drugs to the medium. Sunitinib has a dose-dependent anti-proliferation effect against HuCC-T1 human cholangiocarcinoma cells in vitro. These results indicate that sunitinib-loaded PLCL film is a appropriate candidate as a vehicle for anti-tumor drug delivery.  相似文献   
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