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31.
Increased levels of macrophage migration inhibitory factor (MIF) in serum, sputum, and bronchioalveolar lavage fluid (BALF) from asthmatic patients and time/dose-dependent expression of MIF in eosinophils in response to phorbol myristate acetate suggest the participation of MIF in airway inflammation. In this study, we examined inflammation in OVA-sensitized mouse lungs in wild-type and MIF-deficient mice (MIF(-/-)). We report increased MIF in the lung and BALF of sensitized wild-type mice. MIF(-/-) mice demonstrated significant reductions in serum IgE and alveolar inflammatory cell recruitment. Reduced Th1/Th2 cytokines and chemokines also were detected in serum or BALF from MIF(-/-) mice. Importantly, alveolar macrophages and mast cells, but not dendritic cells or splenocytes, from MIF(-/-) mice demonstrated impaired CD4+ T cell activation, and the reconstitution of wild-type mast cells in MIF(-/-) mice restored the phenotype of OVA-induced airway inflammation, revealing a novel and essential role of mast cell-derived MIF in experimentally induced airway allergic diseases.  相似文献   
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Background

Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens.

Methods

Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study.

Results

Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated.

Conclusion

Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.  相似文献   
34.
Preeclampsia is characterised by new onset hypertension and proteinuria and is a major obstetrical problem for both mother and foetus. Haemolysis elevated liver enzymes and low platelets (HELLP) syndrome is an obstetrical emergency and most cases occur in the presence of preeclampsia. Preeclampsia and HELLP are complicated syndromes with a wide variety in severity of clinical symptoms and gestational age at onset. The pathophysiology depends not only on periconceptional conditions and the foetal and placental genotype, but also on the capability of the maternal system to deal with pregnancy. Genetically, preeclampsia is a complex disorder and despite numerous efforts no clear mode of inheritance has been established. A minor fraction of HELLP cases is caused by foetal homozygous LCHAD deficiency, but for most cases the genetic background has not been elucidated yet. At least 178 genes have been described in relation to preeclampsia or HELLP syndrome. Confined placental mosaicism (CPM) is documented to cause early onset preeclampsia in some cases; the overall contribution of CPM to the occurrence of preeclampsia has not been adequately investigated yet. This article is part of a Special Issue entitled: Molecular Genetics of Human Reproductive Failure.  相似文献   
35.
Sexual development in fungi is a complex process involving the generation of new cell types and tissues - an essential step for all eukaryotic life. The characterization of sterile mutants in the ascomycete Sordaria macrospora has led to a number of proteins involved in sexual development, but a link between these proteins is still missing. Using a combined tandem-affinity purification/mass spectrometry approach, we showed in vivo association of developmental protein PRO22 with PRO11, homologue of mammalian striatin, and SmPP2AA, scaffolding subunit of protein phosphatase 2A. Further experiments extended the protein network to the putative kinase activator SmMOB3, known to be involved in sexual development. Extensive yeast two-hybrid studies allowed us to pinpoint functional domains involved in protein-protein interaction. We show for the first time that a number of already known factors together with new components associate in vivo to form a highly conserved multi-subunit complex. Strikingly, a similar complex has been described in humans, but the function of this so-called striatin interacting phosphatase and kinase (STRIPAK) complex is largely unknown. In S. macrospora, truncation of PRO11 and PRO22 leads to distinct defects in sexual development and cell fusion, indicating a role for the fungal STRIPAK complex in both processes.  相似文献   
36.
Tear proteomic studies revealed distinct similarities between contact lens wearers and dry eye patients. AMO Complete® multipurpose contact lens cleaning solutions containing taurine seem to have a beneficial effect regarding contact lens induced dry eye. To illuminate the effect of taurine on the tear proteome of contact lens wearers and sicca patients we developed a gel-based RP-RP capillary HPLC–MALDI TOF/TOF MS strategy. Two contact lens wearer groups, one using eye drops containing 0.05% taurine; the other for control physiological NaCl solution were monitored. Also, a third group of sicca patients using taurine solution was studied (N = 4 individuals/group). Tear pools of each group at six time points over 5 weeks were analyzed. In summary 267 tear proteins were identified. We found a protein subset showing a linear taurine response with R2 values ≥ 0.5. Taurine effects were detected predominantly in the contact lens group demonstrated by distinct level decreases. Most protein candidates were related to inflammation. Since levels of these proteins differentiate from those of a healthy non-contact lens wearer reference they are supposed to be involved in contact lens induced dry eye and should be focused on in further studies.  相似文献   
37.
Bone tissue has an exceptional quality to regenerate to native tissue in response to injury. However, the fracture repair process requires mechanical stability or a viable biological microenvironment or both to ensure successful healing to native tissue. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. Preclinical and clinical studies using biologic agents like recombinant bone morphogenetic proteins have demonstrated an efficacy similar or better than that of autologous bone graft in acute fracture healing. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications.  相似文献   
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Sepsis and septic shock lead to considerable morbidity and mortality in developed and developing countries. Despite advances in understanding the innate immune events that lead to septic shock, molecular therapies based on these advances have failed to improve sepsis mortality. The clinical failure of laboratory-derived therapies may be, in part, due to the pleiotropic consequences of the acute inflammatory response, which is the focus of this review. A brisk response to infecting organism is essential for pathogen containment and eradication. However, systemic spread of inflammation beyond a single focus leads to organ injury and higher mortality. The primary goal of this article is to discuss recent animal- and human-based scientific advances in understanding the host response to infection and to highlight how these defense mechanisms can be locally beneficial but systemically detrimental. There are other factors that determine the severity of sepsis that are beyond the scope of this review, including the virulence of the pathogen and regulation by Toll-like receptors. Specifically, this review focuses on how the effector mechanisms of platelets, mast cells, neutrophil extracellular traps (NETs), and the endothelium participate in combating local infections yet can induce organ injury during systemic infection.  相似文献   
39.
Food chain models have dominated empirical studies of trophic interactions in the past decades, and have lead to important insights into the factors that control ecological communities. Despite the importance of food chain models in instigating ecological investigations, many empirical studies still show a strong deviation from the dynamics that food chain models predict. We present a theoretical framework that explains some of the discrepancies by showing that trophic interactions are likely to be strongly influenced by the spatial configuration of consumers and their resources. Differences in the spatial scale at which consumers and their resources function lead to uncoupling of the population dynamics of the interacting species, and may explain overexploitation and depletion of resource populations. We discuss how changed land use, likely the most prominent future stress on natural systems, may affect food web dynamics by interfering with the scale of interaction between consumers and their resource.  相似文献   
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