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1.
In the study the aspects noticed on hepatic biopsies by I.F. in HBsAg+ and HBsAg- chronic hepatitis and in some cases of hepatitis on dismetabolic basis in Wilson's disease are compared. Great differences occurred between HBsAg+, HBsAg- and the Hepatitis in Wilson disease. In fact in the first case reactivity is often present due to immunological phenomena (presence of IgG immunocomplexes and autoantibodies) while in Wilson's disease these aspects are not found confirming the hypothesis that in the latter case is a question of an exclusively toxic damage.  相似文献   
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Prostate cancer (PCa) is a leading cause of death among males. It is currently estimated that inflammatory responses are linked to 15-20% of all deaths from cancer worldwide. PCa is dominated by complications arising from metastasis to the bone where the tumor cells interact with the bone microenvironment impairing the balance between bone formation and degradation. However, the molecular nature of this interaction is not completely understood. Heme oxygenase-1 (HO-1) counteracts oxidative damage and inflammation. Previous studies from our laboratory showed that HO-1 is implicated in PCa, demonstrating that endogenous HO-1 inhibits bone derived-prostate cancer cells proliferation, invasion and migration and decreases tumor growth and angiogenesis in vivo. The aim of this work was to analyze the impact of HO-1 modulated PCa cells on osteoblasts proliferation in vitro and on bone remodeling in vivo. Using a co-culture system of PC3 cells with primary mice osteoblasts (PMOs), we demonstrated that HO-1 pharmacological induction (hemin treatment) abrogated the diminution of PMOs proliferation induced by PCa cells and decreased the expression of osteoclast-modulating factors in osteoblasts. No changes were detected in the expression of genes involved in osteoblasts differentiation. However, co-culture of hemin pre-treated PC3 cells (PC3 Hem) with PMOs provoked an oxidative status and activated FoxO signaling in osteoblasts. The percentage of active osteoblasts positive for HO-1 increased in calvarias explants co-cultured with PC3 Hem cells. Nuclear HO-1 expression was detected in tumors generated by in vivo bone injection of HO-1 stable transfected PC3 (PC3HO-1) cells in the femur of SCID mice. These results suggest that HO-1 has the potential to modify the bone microenvironment impacting on PCa bone metastasis.  相似文献   
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A new species of Litomosoides was collected from the abdominal cavity of Oligoryzomys nigripes (Rodentia: Muridae) in a semideciduous secondary rainforest of Misiones, Argentina. Litomosoides odilae n. sp. belongs to the carinii group and is characterized by the amphids displaced dorsally; buccal capsule with an anterior segment transparent and an annular asymmetrical thickening; esophagus divided, with the posterior glandular portion slightly wider than the muscular; male cloacal aperture strongly protruded; and microfilaria sheathed with an attenuated tail. The morphology of the new species, which is similar to that of L petteri, a parasite of marsupials in Brazil, suggests that host-switching events may have occurred in the diversification of this genus.  相似文献   
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Systemic sclerosis is an autoimmune disease characterized by immunological and vascular abnormalities. Autoantibodies against intracellular antigens are associated with particular clinical features of the disease, whereas autoantibodies against cell surface antigens may be pathogenic by inducing endothelial cell damage, considered the primary event in the pathogenesis of the disease. Latent human cytomegalovirus infection may contribute to progression of systemic sclerosis through its ability to infect endothelial cells; however, direct links between human cytomegalovirus infection and systemic sclerosis are still lacking. Molecular mimicry is one of the mechanisms that account for the link between infection and autoimmunity. Here we have identified an immunodominant peptide using systemic sclerosis serum screening of a random peptide library; such peptide shares homology with autoantigens and with the human cytomegalovirus late protein UL94 (ref. 9). Immunoglobulin G antibodies against the peptide affinity-purified from the sera of patients with systemic sclerosis specifically recognized the viral product and autoantigens; moreover, such antibodies induced endothelial cell apoptosis through specific interaction with the cell surface integrin-NAG-2 protein complex. Our results provide evidence that antibodies against human cytomegalovirus cause apoptosis of endothelial cells, considered the initial pathogenic event of systemic sclerosis, and indicate a previously unknown mechanism for the etiological link between human cytomegalovirus infection and autoimmunity.  相似文献   
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The life history of Ascarophis marina in Argentina is proposed on the basis of morphometric features of larval and adult specimens, as well as of trophic relationships among invertebrate and vertebrate hosts in the same geographic area. Adult and larval specimens of A. marina were found in the alimentary tract of the teleost fishes Parona signata (Carangidae) and Urophycis brasiliensis (Gadidae). Third-stage larvae ocurred in the shrimps Peisos petrunkevitchi (Sergestidae) and Artemesia longinaris (Penaeidae).  相似文献   
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Parasitoids (Hymenoptera) associated with agromyzid leafminers (Diptera: Agromyzidae) were studied in three rural farms located in northern Italy. The parasitoids were reared from mined foliage of weeds growing in field margins. We reared 998 Hymenoptera specimens, representing five families, 23 genera, and 53 species, from leafminers infesting weeds. Eulophidae was the most abundant family (67.64%), followed by Braconidae (28.86%), Eucoilinae (1.40%), Tetracampidae (1.40%), and Pteromalidae (0.7%). Braconids was the most species rich family, accounting for 28 species; eulophids were represented by 19 species, pteromalids by four species, and eucoilins and tetracampids by one species each. The dominant parasitoid was the eulophid Pediobius metallicus (Nees), representing 18.17% of the total, followed by Diglyphus isaea (Walker) (12.73%), and Neochrysocharis formosa (Westwood) (10.82%). The most abundant braconid parasitoid was Dacnusa maculipes Thomson (9.62%). More than 80% of parasitoids were recovered from 10 plant species: Cirsium arvense (L.) Scopoli, Plantago lanceolata L., Sonchus asper (L.) Hill, Papaver rhoeas L., Picris echioides L., Lactuca serriola L., Myagrum perfoliatum L., Ranunculus velutinus Tenore, Arctium lappa L., and Medicago sativa L. The retention and the management of wild plants within field margins can be crucial tools to enhance the populations of biological control agents of agromyzids and to conserve rare parasitic wasp species.  相似文献   
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Streptomyces species are native inhabitants of soil, a natural environment where nutrients can be scarce and competition fierce. They have evolved ways to metabolize unusual nutrients, such as purines and its derivatives, which are highly abundant in soil. Catabolism of these uncommon carbon and nitrogen sources needs to be tightly regulated in response to nutrient availability and environmental stimulus. Recently, the allantoin degradation pathway was characterized in Streptomyces coelicolor. However, there are questions that remained unanswered, particularly regarding pathway regulation. Here, using a combination of proteomics and genetic approaches, we identified the negative regulator of the allantoin pathway, AllR. In vitro studies confirmed that AllR binds to the promoter regions of allantoin catabolic genes and determined the AllR DNA binding motif. In addition, effector studies showed that allantoic acid, and glyoxylate, to a lesser extent, inhibit the binding of AllR to the DNA. Inactivation of AllR repressor leads to the constitutive expression of the AllR regulated genes and intriguingly impairs actinorhodin and undecylprodigiosin production. Genetics and proteomics analysis revealed that among all genes from the allantoin pathway that are upregulated in the allR mutant, the hyi gene encoding a hydroxypyruvate isomerase (Hyi) is responsible of the impairment of antibiotic production.  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   
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