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991.
Although, vascular remodeling is a hallmark of many chronic inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, anti-vascular strategies to treat these conditions have received little attention to date. We investigated the anti-inflammatory activity of systemic blockade of VEGF-A by the inhibitory monoclonal antibody G6–31, employing a therapeutic trial in a mouse model of psoriasis. Simultaneous deletion of JunB and c-Jun (DKO*) in the epidermis of adult mice leads to a psoriasis-like phenotype with hyper- and parakeratosis and increased subepidermal vascularization. Moreover, an inflammatory infiltrate and elevated levels of cytokines/chemokines including TNFα, IL-1α/β, IL-6, and the innate immune mediators IL-22, IL-23, IL-23R, and IL-12p40 are detected. Here we show that anti-VEGF antibody treatment of mice already displaying disease symptoms resulted in an overall improvement of the psoriatic lesions leading to a reduction in the number of blood vessels and a significant decrease in the size of dermal blood and lymphatic vessels. Importantly, anti-VEGF–treated mice showed a pronounced reduction of inflammatory cells within the dermis and a normalization of epidermal differentiation. These results demonstrate that systemic blockade of VEGF by an inhibitory antibody might be used to treat patients who have inflammatory skin disorders such as psoriasis.  相似文献   
992.
Botulinum neurotoxins, predominantly serotypes C and D, cause equine botulism through forage poisoning. The C-terminal part of the heavy chain of botulinum neurotoxin types C and D (HcBoNT/C and D) was expressed in Escherichia coli and evaluated as a recombinant mono- and bivalent vaccine in twelve horses in comparison to a commercially available toxoid vaccine. A three-dose subcutaneous immunization of adult horses elicited robust serum antibody response in an ELISA using the immunogen as a capture antigen. Immune sera showed dose-dependent high potency in neutralizing specifically the active BoNT/C and D in the mouse protection assay. The aluminium hydroxide based mono- and bivalent recombinant HcBoNT/C and D vaccines were characterized by good compatibility and the ability to elicit protective antibody titers similar or superior to the commercially available toxoid vaccine.  相似文献   
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995.
Volumetric imaging and planning for 3-dimensional (3D) conformal radiotherapy and intensity-modulated radiotherapy (IMRT) have highlighted the need to the oncology community to better understand the geometric uncertainties inherent in the radiotherapy delivery process, including setup error (interfraction) as well as organ motion during treatment (intrafraction). This has ushered in the development of emerging technologies and clinical processes, collectively referred to as image-guided radiotherapy (IGRT). The goal of IGRT is to provide the tools needed to manage both inter- and intrafraction motion to improve the accuracy of treatment delivery. Like IMRT, IGRT is a process involving all steps in the radiotherapy treatment process, including patient immobilization, computed tomography (CT) simulation, treatment planning, plan verification, patient setup verification and correction, delivery, and quality assurance. The technology and capability of the Dynamic Targeting IGRT system developed by Varian Medical Systems is presented. The core of this system is a Clinac or Trilogy accelerator equipped with a gantry-mounted imaging system known as the On-Board Imager (OBI). This includes a kilovoltage (kV) x-ray source, an amorphous silicon kV digital image detector, and 2 robotic arms that independently position the kV source and imager orthogonal to the treatment beam. A similar robotic arm positions the PortalVision megavoltage (MV) portal digital image detector, allowing both to be used in concert. The system is designed to support a variety of imaging modalities. The following applications and how they fit in the overall clinical process are described: kV and MV planar radiographic imaging for patient repositioning, kV volumetric cone beam CT imaging for patient repositioning, and kV planar fluoroscopic imaging for gating verification. Achieving image-guided motion management throughout the radiation oncology process requires not just a single product, but a suite of integrated products to manipulate all patient data, including images, efficiently and effectively.  相似文献   
996.
We report two cases of coronary artery disease treated percutaneously and including rotational atherectomy, in which the interventional procedure was complicated by left main coronary artery perforation. The management and outcome of this potentially fatal complication are discussed.  相似文献   
997.
998.
The immunization of goats with a synthetic peptide encompassing the G5 antigenic site of the rabies virus surface glycoprotein induces a strong humoral immune response in the absence of a carrier protein. The immunized animals mounted high antibody titers and showed a strong avidity maturation of the B cell immune response to both the G5-peptide and purified surface glycoprotein G. This antibody weakly neutralized rabies virus carrying the G5 epitope but failed to neutralize escape mutants carrying a single point mutation in this epitope. A putative T helper cell epitope, functional in the context of different caprine MHC haplotypes, was identified by structure analysis of the G5-peptide. This striking dichotomy between high titers and antibody of high avidity to the glycoprotein G and poor neutralizing activity strongly suggests that antibody binding assays such as ELISA cannot always reliably predict the neutralizing activity of sera as measured in functional assays.  相似文献   
999.
BACKGROUND: Cytomegalovirus (CMV) antibody donor screening assays have predominantly included both immunoglobulin G (IgG) and immunoglobulin M (IgM) detection. However, since in the majority of cases both CMV IgG and IgM are detected concomitantly during early seroconversion, CMV assays based only on IgG are now widely applied for donor screening.
STUDY DESIGN AND METHODS: The performance of an automated microparticle CMV IgG assay (Abbott AxSYM CMV IgG microparticle enzyme immunoassay [MEIA]) was compared with an established total antibody blood screening assay (Abbott CMV Total AB EIA). Sensitivity and specificity were assessed using 5050 random blood donors and 13 seroconversion panels. A risk analysis was undertaken to estimate the residual risk of transfusion-transmitted CMV (TT-CMV) from presumptive seronegative blood components.
RESULTS: The EIA achieved marginally (but not significantly) better resolved sensitivity (100%) than the AxSYM IgG assay (99.93%). The AxSYM IgG resolved specificity (99.34%) was superior to the EIA (96.4%). This superiority was maintained (98.61%) when a modified cutoff was applied to the AxSYM IgG assay to achieve 100 percent resolved sensitivity. The seroconversion sensitivities of the EIA and the AxSYM IgG were equivalent, detecting the same bleed as positive in the majority of the seroconversion panels tested. The median TT-CMV residual risk estimate for the two assays was approximately 1 in 66,000 (range, 42,000-165,000).
CONCLUSION: The AxSYM IgG MEIA is suitable for blood donor screening and was optimized by applying a modified cutoff of 9 AU per mL. The modeling predicts that implementing the AxSYM IgG assay would not negatively impact the already very low risk of TT-CMV associated with seronegative blood components in Australia.  相似文献   
1000.
Background  Pearson marrow-pancreas syndrome (PS) is usually a fatal mitochondrial disease, mostly diagnosed during infancy or postmortem. PS is caused by the deletions or duplications of mitochondrial DNA (mtDNA). The tissue distribution and relative proportions of expressed abnormal mtDNA determine the phenotype and the clinical course. Materials and methods  We describe the case of a term baby boy who was diagnosed with PS early in the neonatal period due to severe aregenerative anemia and persistent lactic acidosis. Results  His neurological examination was abnormal since birth. Brain magnetic resonance imaging (MRI) at term was abnormal, indicating that mitochondrial encephalopathy in PS can be already manifested in the neonatal period. To our knowledge, neonatal encephalopathy in PS has not been previously described. Conclusion  PS is a rare condition diagnosed in the newborn. It should be suspected in the presence of severe anemia and persistent lactic acidosis, and may manifest with early encephalopathy.  相似文献   
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