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1.
Genetically modified mice offer a wide range of possibilities in preclinical drug discovery, e.g. for use in target identification, target validation and disease model generation. However, genomic modification and alteration in gene expression may cause unpredicted phenotypic alterations in the organism other than the intended ones. The aim of this study was to determine the importance of establishing the phenotype of transgenic and knockout mice models for use in pharmaceutical research.

A total number of 51 mouse models (transgenic and knockout) produced at AstraZeneca during a 4 year period were subjected to a thorough phenotyping package covering clinical as well as morphological aspects. Phenotype abnormalities were recorded in 36 (70.6%) of the mouse models. The majority of findings were considered to be minor in magnitude. Histopathological changes related to the genotype of the animals were observed in 33% of the mouse models, underlining the importance of pathology in the phenotyping program.  相似文献   

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Vaccination against smallpox is again considered in order to face a possible bioterrorist threat, but the nature and the level of the immune response needed to protect a person from smallpox after vaccination are not totally understood. Therefore, simple, rapid, and accurate assays to evaluate the immune response to vaccinia virus need to be developed. Neutralization assays are usually considered good predictors of vaccine efficacy and more informative with regard to protection than binding assays. Currently, the presence of neutralizing antibodies to vaccinia virus is measured using a plaque reduction neutralization test, but this method is time-consuming and labor-intensive and has a subjective readout. Here, we describe an innovative neutralization assay based on a modified vaccinia virus Ankara (MVA) vector expressing the green fluorescent protein (MVA-gfp). This MVA-gfp neutralization assay is rapid and sensitive and has a high-throughput potential. Thus, it is suitable to monitor the immune response and eventually the efficacy of a large campaign of vaccination against smallpox and to study the vector-specific immune response in clinical trials that use genetically engineered vaccinia viruses. Most importantly, application of the highly attenuated MVA eliminates the safety concern in using the replication-competent vaccinia virus in the standard clinical laboratory.  相似文献   
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Background  

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). It is associated with local activation of microglia and astroglia, infiltration of activated macrophages and T cells, active degradation of myelin and damage to axons and neurons. The proposed role for CX3CL1 (fractalkine) in the control of microglia activation and leukocyte infiltration places this chemokine and its receptor CX3CR1 in a potentially strategic position to control key aspects in the pathological events that are associated with development of brain lesions in MS. In this study, we examine this hypothesis by analyzing the distribution, kinetics, regulation and cellular origin of CX3CL1 and CX3CR1 mRNA expression in the CNS of rats with an experimentally induced MS-like disease, myelin oligodendrocyte glycoprotein (MOG)-induced autoimmune encephalomyelitis (EAE).  相似文献   
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Background  

The CC chemokine receptors CCR1, CCR2 and CCR5 are critical for the recruitment of mononuclear phagocytes to the central nervous system (CNS) in multiple sclerosis (MS) and other neuroinflammatory diseases. Mononuclear phagocytes are effector cells capable of phagocytosing myelin and damaging axons. In this study, we characterize the regional, temporal and cellular expression of CCR1, CCR2 and CCR5 mRNA in the spinal cord of rats with myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis (MOG-EAE). While resembling human MS, this animal model allows unique access to CNS-tissue from various time-points of relapsing neuroinflammation and from various lesional stages: early active, late active, and inactive completely demyelinated lesions.  相似文献   
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Purpose: To investigate strabismus, head posture, nystagmus, stereoacuity, ocular motility, near point of convergence (NPC) and accommodative convergence to accommodation ratio (AC/A) in a sample of Swedish children. Methods: A prospective cross-sectional study was carried out on 143 children, 4–15 years of age. Results: Heterotropia was found in five children (3.5%), four with esotropia and one with exotropia. One child with esotropia had a slight overaction of both inferior oblique muscles. Heterophoria was found in 37 children (26%) at near and/or distance fixation and it was four times more common at near than at distance. In 29 children, heterophoria was found at one distance only and orthophoria at the other. Orthophoria at both near and distance fixation was noted in 101 children (70.5%). The near point of convergence was ≤6 cm in 97% of the children and 97% had stereoacuity of 60″ or better. In the whole group, the median AC/A ratio calculated with the heterophoria method was 5.6/1 prism diopters/diopters (PD/D) and with the gradient method, 1.3/1 PD/D. No anomalous head postures or nystagmus were observed and all children had normal versions. Conclusion: In this study, 143 well-defined children were investigated with a battery of accurately described tests, commonly used in clinical practice. These results are in agreement with those of other studies examining one or few variables in larger populations and the authors therefore conclude that their results may be used for comparisons with different patient groups.  相似文献   
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Overweight and obesity carry a tremendous burden in terms of physiological and psychological comorbidities. There is a great variety of weight management applications to support weight reduction, but a systematical analysis of individuals’ needs and requirements to adopt sustaining lifestyle changes is missing so far. This study aimed to assess the acceptance of such applications and its underlying predictors in individuals with overweight/obesity. A cross-sectional study was conducted, including 439 overweight/obese individuals. Health-related internet use and acceptance of weight management applications were examined using a modified questionnaire based on the Unified Theory of Acceptance and Use of Technology (UTAUT). The general acceptance of weight management applications was high, with significant age differences. Compared to older individuals, younger ones showed a higher acceptance. BMI was not significantly associated with acceptance. Besides psychometric data and eHealth-related data, performance expectancy, effort expectancy, and social influence proved to be significant predictors for acceptance. The total variance explanation provided by the extended UTAUT model was 61.2%. The knowledge of the influencing factors on acceptance might be useful in developing, optimizing, and establishing weight management applications. For determining acceptance and its predictors of weight management applications, the UTAUT model is a valid approach.  相似文献   
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Purpose of review

Ionizing radiation is a highly effective treatment for a wide range of malignancies, yet the cardiovascular (CV) toxicity that can result from chest radiotherapy impairs the long-term health of cancer survivors and can be a limiting factor for its use. Despite over 100 years of successful clinical use, the mechanisms by which high-energy photons damage critical components within cells of the heart’s myocardium, pericardium, vasculature, and valves remain unclear.

Recent findings

Recent studies exploring the acute and chronic effects of radiation therapy on cardiac and vascular tissue have provided new insights into the development and progression of heart disease, including the identification and understanding of age- and complication-associated risk factors. However, key questions relating to the connection from upstream signaling to fibrotic changes remain. In addition, advances in the delivery of chest radiotherapy have helped to limit heart exposure and damage, but additional refinements to delivery techniques and cardioprotective therapeutics are absolutely necessary to reduce patient mortality and morbidity.

Summary

Radiation therapy (RT)-driven CV toxicity remains a major issue for cancer survivors and more research is needed to define the precise mechanisms of toxicity. However, recent findings provide meaningful insights that may help improve patient outcomes.
  相似文献   
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