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41.
Coxsackievirus B3-associated myocardial pathology and viral load reduced by recombinant soluble human decay-accelerating factor in mice 总被引:10,自引:0,他引:10
Yanagawa B Spiller OB Choy J Luo H Cheung P Zhang HM Goodfellow IG Evans DJ Suarez A Yang D McManus BM 《Laboratory investigation; a journal of technical methods and pathology》2003,83(1):75-85
Coxsackievirus B3 (CVB3) infection can result in myocarditis, which in turn may lead to a protracted immune response and subsequent dilated cardiomyopathy. Human decay-accelerating factor (DAF), a binding receptor for CVB3, was synthesized as a soluble IgG1-Fc fusion protein (DAF-Fc). In vitro, DAF-Fc was able to inhibit complement activity and block infection by CVB3, although blockade of infection varied widely among strains of CVB3. To determine the effects of DAF-Fc in vivo, 40 adolescent A/J mice were infected with a myopathic strain of CVB3 and given DAF-Fc treatment 3 days before infection, during infection, or 3 days after infection; the mice were compared with virus alone and sham-infected animals. Sections of heart, spleen, kidney, pancreas, and liver were stained with hematoxylin and eosin and submitted to in situ hybridization for both positive-strand and negative-strand viral RNA to determine the extent of myocarditis and viral infection, respectively. Salient histopathologic features, including myocardial lesion area, cell death, calcification and inflammatory cell infiltration, pancreatitis, and hepatitis were scored without knowledge of the experimental groups. DAF-Fc treatment of mice either preceding or concurrent with CVB3 infection resulted in a significant decrease in myocardial lesion area and cell death and a reduction in the presence of viral RNA. All DAF-Fc treatment groups had reduced infectious CVB3 recoverable from the heart after infection. DAF-Fc may be a novel therapeutic agent for active myocarditis and acute dilated cardiomyopathy if given early in the infectious period, although more studies are needed to determine its mechanism and efficacy. 相似文献
42.
Previous cognitive vulnerability studies have identified sociotropy/dependency as a personality characteristic related to depression. We evaluated sociotropy in differential prediction of depression vs. anxiety. Participants (70 females, 42 males) were tested on the Beck Depression Inventory (BDI) and the Beck Anxiety Inventory (BAI) at two points in time (T1 and T2), separated by an interval of 4 weeks. The Sociotropy‐Autonomy Scale (SAS) was administered at T1. Sociotropy was related moderately to the BDI at T1 and T2, but also to the BAI. Autonomy was related to neither. Hierarchical multiple regression analyses found sociotropy to predict anxiety at T2, but not depression. The issue of cognitive vulnerability marker specificity is discussed. © 2003 Wiley Periodicals, Inc. J Clin Psychol, 2003. 相似文献
43.
A mutation in the gene TNFRSF11B encoding osteoprotegerin causes an idiopathic hyperphosphatasia phenotype 总被引:5,自引:0,他引:5
44.
45.
Fgf-10 is required for both limb and lung development and exhibits striking functional similarity to Drosophila branchless 总被引:11,自引:1,他引:11
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Hosung Min Dimitry M. Danilenko Sheila A. Scully Brad Bolon Brian D. Ring John E. Tarpley Margaret DeRose W. Scott Simonet 《Genes & development》1998,12(20):3156-3161
Fgf-10-deficient mice (Fgf-10−/−) were generated to determine the role(s) of Fgf-10 in vertebrate development. Limb bud initiation was abolished in Fgf-10−/− mice. Strikingly, Fgf-10−/− fetuses continued to develop until birth, despite the complete absence of both fore- and hindlimbs. Fgf-10 is necessary for apical ectodermal ridge (AER) formation and acts epistatically upstream of Fgf-8, the earliest known AER marker in mice. Fgf-10−/− mice exhibited perinatal lethality associated with complete absence of lungs. Although tracheal development was normal, main-stem bronchial formation, as well as all subsequent pulmonary branching morphogenesis, was completely disrupted. The pulmonary phenotype of Fgf-10−/− mice is strikingly similar to that of the Drosophila mutant branchless, an Fgf homolog. 相似文献
46.
Avian cryptococcosis. 总被引:2,自引:0,他引:2
R Malik M B Krockenberger G Cross R Doneley D N Madill D Black P McWhirter A Rozenwax K Rose M Alley D Forshaw I Russell-Brown A C Johnstone P Martin C R O'Brien D N Love 《Medical mycology》2003,41(2):115-124
Clinical and laboratory findings in 15 unreported cases of avian cryptococcosis from Australia were collated and contrasted with 11 cases recorded in the literature. Cryptococcus species produced localized invasive disease of the upper respiratory tract of captive parrots living in Australia. This resulted in signs referable to mycotic rhinitis or to involvement of structures contiguous with the nasal cavity, such as the beak, sinuses, choana, retrobulbar space and palate. Parrots of widely differing ages were affected and of the seven birds for which sex was determinable, six were male. Cryptococcus bacillisporus (formerly C. neoformans var. gattii) accounted for four of five infections in which the species or variety was determinable, suggesting that exposure to eucalyptus material may be a predisposing factor. In these cases, Cryptococcus appeared to behave as a primary pathogen of immunocompetent hosts. One tissue specimen was available from an Australian racing pigeon with minimally invasive subcutaneous disease; immunohistology demonstrated a C. neoformans var. grubii (formerly C. neoformans var. neoformans serotype A) infection, presumably subsequent to traumatic inoculation of yeast cells into the subcutis. Two similar cases had been reported previously in pigeons domiciled in America. Data for parrots, one pigeon and other birds studied principally in America and Europe (and likely infected with C. neoformans) suggested a different pattern of disease, more suggestive of opportunistic infection of immunodeficient hosts. In this cohort of patients, the organism was not restricted to cool superficial sites such as the upper respiratory tract or subcutis. Instead, infections typically penetrated the lower respiratory tract or disseminated widely to a variety of internal organs. Finally, three captive North Island brown kiwis, one residing in Australia, the other two in New Zealand, died as a result of severe diffuse cryptococcal pneumonia (two cases) or widely disseminated disease (one case). C. bacillisporus strains were isolated from all three cases, as reported previously for another kiwi with disseminated disease in New Zealand. 相似文献
47.
The ability of Staphylococcus aureus conjugative plasmids to mobilise non-conjugative resistance plasmids from clinical isolates of S. aureus and S. epidermidis was studied. Plasmids which could not be transferred by transduction or mixed-culture transfer were transferred from phage-typable and non-typable S. aureus and from S. epidermidis. Plasmids encoding single resistance determinants were transferred by mobilisation whereas multiple-resistance plasmids were transferred as co-integrates between the conjugative and non-conjugative plasmids. This study demonstrates that mobilisation is a useful tool for the transfer and study of staphylococcal plasmids and illustrates how antibiotic resistance could be transferred between staphylococci in vivo. 相似文献
48.
Bruce Guthrie Tom Love Rebecca Kaye Margaret MacLeod Jim Chalmers 《The British journal of general practice》2008,58(550):311-317
BACKGROUND: The Shipman Inquiry recommended mortality rate monitoring if it could be 'shown to be workable' in detecting a future mass murderer in general practice. AIM: To examine the effectiveness of cumulative sum (CUSUM) charts, cross-sectional Shewhart charts, and exponentially-weighted, moving-average control charts in mortality monitoring at practice level. DESIGN OF STUDY: Analysis of Scottish routine general practice data combined with estimation of control chart effectiveness in detecting a 'murderer' in a simulated dataset. METHOD: Practice stability was calculated from routine data to determine feasible lengths of monitoring. A simulated dataset of 405,000 'patients' was created, registered with 75 'practices' whose underlying mortality rates varied with the same distribution as case-mix-adjusted mortality in all Scottish practices. The sensitivity of each chart to detect five and 10 excess deaths was examined in repeated simulations. The sensitivity of control charts to excess deaths in simulated data, and the number of alarm signals when control charts were applied to routine data were estimated. RESULTS: Practice instability limited the length of monitoring and modelling was consequently restricted to a 3-year period. Monitoring mortality over 3 years, CUSUM charts were most sensitive but only reliably achieved >50% successful detection for 10 excess deaths per year and generated multiple false alarms (>15%). CONCLUSION: At best, mortality monitoring can act as a backstop to detect a particularly prolific serial killer when other means of detection have failed. Policy should focus on changes likely to improve detection of individual murders, such as reform of death certification and the coroner system. 相似文献
49.
Combined natural killer cell and dendritic cell functional deficiency in KARAP/DAP12 loss-of-function mutant mice 总被引:13,自引:0,他引:13
Tomasello E Desmoulins PO Chemin K Guia S Cremer H Ortaldo J Love P Kaiserlian D Vivier E 《Immunity》2000,13(3):355-364
KARAP/DAP12 is a transmembrane polypeptide with an intracytoplasmic immunoreceptor tyrosine-based activation motif (ITAM). KARAP/DAP12 is associated with several activating cell surface receptors in hematopoietic cells. Here, we report that knockin mice bearing a nonfunctional KARAP/DAP12 ITAM present altered innate immune responses. Although in these mice NK cells are present and their repertoire of inhibitory MHC class I receptors is intact, the NK cell spectrum of natural cytotoxicity toward tumor cell targets is restricted. KARAP/DAP12 loss-of-function mutant mice also exhibit a dramatic accumulation of dendritic cells in muco-cutaneous epithelia, associated with an impaired hapten-specific contact sensitivity. Thus, despite its homology with CD3zeta and FcRgamma, KARAP/DAP12 plays a specific role in innate immunity, emphasizing the nonredundancy of these ITAM-bearing polypeptides in hematopoietic cells. 相似文献
50.
Foskey M Davis B Goyal L Chang S Chaney E Strehl N Tomei S Rosenman J Joshi S 《Physics in medicine and biology》2005,50(24):5869-5892
In this paper, we present and validate a framework, based on deformable image registration, for automatic processing of serial three-dimensional CT images used in image-guided radiation therapy. A major assumption in deformable image registration has been that, if two images are being registered, every point of one image corresponds appropriately to some point in the other. For intra-treatment images of the prostate, however, this assumption is violated by the variable presence of bowel gas. The framework presented here explicitly extends previous deformable image registration algorithms to accommodate such regions in the image for which no correspondence exists. We show how to use our registration technique as a tool for organ segmentation, and present a statistical analysis of this segmentation method, validating it by comparison with multiple human raters. We also show how the deformable registration technique can be used to determine the dosimetric effect of a given plan in the presence of non-rigid tissue motion. In addition to dose accumulation, we describe a method for estimating the biological effects of tissue motion using a linear-quadratic model. This work is described in the context of a prostate treatment protocol, but it is of general applicability. 相似文献