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Streptococcus bovis is one of the nonenterococcal species included among the streptococci group D. It is part of the normal bowel flora in humans and animals, but it is also responsible for infectious diseases (10-15% of all cases of bacterial endocarditis). Many cases of bacteremia and metastatic abscesses (spleen, liver, soft tissues, bone, meninges, endocardium) caused by S. bovis were reported as associated with digestive tract diseases, mainly colonic disease, and, in particular colonic neoplasms, or chronic liver diseases. A role in carcinogenesis has been suggested for this microorganism. The authors report two cases of S. bovis sepsis, one associated with colonic neoplasm and the other with liver cirrhosis and gastric carcinoma. Discussion is focused on probable mechanisms that favor gastric colonization and systemic diffusion of S. bovis from the gut in patients with gastrointestinal neoplasms or chronic liver disease and provides clinical recommendations for patients with S. bovis infections.  相似文献   
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Background

The interpretation of “indeterminate” results of the recombinant immunoblot assay (RIBA) is a particularly sensitive issue for Transfusion Services, and donors with such a serological condition require long-term follow-up.

Materials and methods

In the Immunohaematology and Transfusion Medicine Division of Umberto I University Hospital (Rome, Italy), 102,979 donor blood units were screened for hepatitis C virus (HCV) antibodies by enzyme-linked immunosorbent assay (ELISA) over a 5-year period (01.01.2000 – 31.12.2004). Since 24.10.2001, HCV -RNA testing was added. All samples repeatedly reactive by ELISA were then submitted to a HCV confirmatory assay (RIBA).

Results

Among the 102,979 donors we found 271 positive to HCV ELISA testing. The results of the RIBA assay for these donors were negative in 178 (65.7%) cases, positive in 28 (10.3%) and indeterminate in 65 (24.0 %).Of the 65 subjects with an indeterminate pattern, 24 completed a sufficient follow-up (median 25 months; range, 6 – 52), during which some (n=8; 33%) converted to a negative status, some (n=16; 67%) maintained their reactivity pattern, but none became seropositive for HCV.

Conclusions

The HCV-RIBA indeterminate status may indicate either a non-specific reaction (false positive) or a real pre-existing or initial infection and does not, therefore, enable a prediction of outcome. The use of HCV genomic assays (nucleic acid amplification testing), which are more specific than antibody-based assays (ELISA, RIBA), therefore improves HCV blood donor testing by allowing an accurate interpretation of such primary assays.  相似文献   
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Introduction: Inhaled corticosteroids are the only drugs that effectively suppress the airway inflammation, but they can induce considerable systemic and adverse effects when they are administered chronically at high doses. Consequently, the pharmaceutical industry is still searching for newer entities with an improved therapeutic index.

Areas covered: Herein, the authors review the research in the glucocorticoid field to identify ligands of the glucocorticoid receptor (GR). These ligands preferentially induce transrepression with little or no transactivating activity, in order to have a potent anti-inflammatory action and a low side-effects profile.

Expert opinion: Several agents have been synthesized, but few have been tested in experimental models of asthma. Furthermore, only three (BI-54903, GW870086X and AZD5423) have entered clinical development, although the development of at least one of them (BI-54903) was discontinued. The reason for the limited success so far obtained is that the model of transactivation versus transrepression is a too simplistic representation of GR activity. It is difficult to uncouple the therapeutic and harmful effects mediated by GR, but some useful information that might change the current perspective is appearing in the literature. The generation of gene expression ‘fingerprints’ produced by different GR agonists in target and off-target human tissues could be useful in identifying drug candidates with an improved therapeutic ratio.  相似文献   

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