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Black-pigmented anaerobic rods such as Prevotella spp. and Porphyromonas spp. are involved in the etiology and perpetuation of endodontic infections. The aim of this study was to evaluate the prevalence of these species in chronic endodontic infections by using culture and polymerase chain reaction (PCR) techniques. Samples of 100 patients with root canals displaying chronic endodontic infections were obtained by sterilized paper points. Bacterial identification was performed by using culture and PCR techniques. By culture, in 33% of the samples, P. intermedia-P. nigrescens (75.8%), P. gingivalis (27.3%), and P. endodontalis (9.1%) were identified, and by PCR 60% of the samples harbored P. nigrescens (43.3%), P. gingivalis (43.3%), P. intermedia (31.7%), and P. endodontalis (23.3%). The presence of these black-pigmented anaerobic rods alone or in association in chronic endodontic infections seems to be frequent. PCR is a very sensitive technique for detecting DNA from bacterial cells. Culturing is only able to reveal living bacteria and is less sensitive for the identification of low numbers of bacterial cells.  相似文献   
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Background Pityrosporum ovale is a common saprophyte on the skin capable of inducing IgE antibody production in atopic dermatitis (AD) patients. Allergens ofP. ovale have been examined in several studies, but consensus on them is lacking. Objective This study was carried out to obtain more information about the IgE antibody response against P. ovale. including niunnun. Methods Sera from 64 AD patients and 10 healthy controls were analysed with immuno-blotting and the nitrocellulose radio allergosorbent test (RAST) method specifically developed to detect antimannan P. ovale IgE antibodies. Results In immunoblotting a total of 39 different IgE stained protein bands were seen. A high molecular weight staining was also seen especially in patients who displayed elevated mannan P. ovale RAST values. The most commonly stained protein bands in immunoblotting were 9 and 96 kD bands with antibodies in 73 and 65% of AD patients who had been positive in commercial P. orbiculare RAST with total serum IgE less than 4000 kU/I. Mannan RAST appeared positive in 77% of them. Positive immunoblotting to either of these bands was seen in 90% and, if added with staining with ihe 20 kD band, in 100% of these AD patients. A comhination of 9 kD IgE staining and mannan P. ovale RAST was positive in 92% of the patients and % kD and mannan P. ovale RAST in 85% of the patients. Conclusion It is evident that P. ovale has several allergens, the 9. 96 and 20 kD regions being the most important. According to our results mannan is also an important allegen of P. ovale  相似文献   
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Species-level identification of Acanthamoeba isolates is difficult and gives little or no indication of the isolate's pathogenicity. We identified two amplification-based genetic markers that were highly correlated with pathogenicity in Acanthamoeba spp. One marker, designed to amplify a 485-bp fragment of the small-subunit ribosomal RNA gene (ssrDNA), was preferentially amplified from the nonpathogenic strains; amplifications from the pathogenic strains yielded anomalous fragments of 650 and 900?bp. A second marker was developed on the basis of the anomalous 650-bp fragment. Primers to this sequence preferentially amplified a noncoding locus (called Ac6) only from the pathogenic strains. These two genetic markers may be useful for identification of pathogenic Acanthamoeba spp. strains.  相似文献   
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We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function.  相似文献   
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