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1.
Purpose We report a case of periocular subcutaneous macrofilariasis as an initial sign of a systemic Loa loa infection.Methods Thorough history, eye examination and surgical intervention. Parasitological and serological analysis.Results A periocular adult Loa loa worm was extracted from the left upper eyelid in an African student living in Germany after presenting to our department with intermittent attacks of painful lid swelling. Four weeks later he presented with Calabar swellings in his arms without serological evidence of microfilaria and was treated with diethylcarbamazine.Conclusion Due to increasing migration of populations to Europe rare manifestations of ocular loiasis are becoming more common. Intermittent painful eyelid swelling in patients who visited or have lived in Africa should always raise the suspicion of systemic loiasis.  相似文献   
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Bartonella henselae is the primary agent of cat scratch disease (CSD). In order to study the genetic variation of B. henselae and the correlation of the various genotypes with epidemiological and clinical findings, two seminested, groEL- and pap31-based PCR assays were carried out with specimens from 273 patients. Amplicons were sequenced to determine the genotype of the causative Bartonella species. Compared to our reference intergenic spacer region-based PCR, the groEL- and pap31-based assays were 1.7 and 1.9 times more sensitive, respectively. All 107 positive patients were infected with B. henselae; neither Bartonella clarridgeiae nor other species were detected. Based on the groEL and pap31 sequences, B. henselae amplicons were classified into two genogroups, Marseille and Houston-1, and into four variants, Marseille, CAL-1, Houston-1, and a new variant, ZF-1. Patients infected with either one or the other genogroup did not exhibit different epidemiological or clinical characteristics. Our study highlights the genotypic heterogeneity of B. henselae in patients with CSD.  相似文献   
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We describe a large inbred Sicilian family that includes four 46, XX (SRY-) brothers. Palmoplantar hyperkeratosis (PPK) and an associated predisposition to squamous cell carcinoma (SCC) of the skin, segregates as a recessive trait within the family. Interestingly, all the PPK-affected members of the family are phenotypic males (46,XY or 46,XX) while seven XX sibs are healthy phenotypic females with no signs of PPK. We propose that homozygosity for a single mutational event, possibly including contiguous genes, may cause PPK/SCC in both XY or XX individuals and sex reversal in XX individuals. The family is informative for linkage analysis for the PPK trait and allows linkage exclusion for the sex reversal trait. Here we show that 15 loci involved in PPK etiology, skin differentiation, function or malignancy, and nine loci involved in sex determination/differentiation are not implicated in the phenotype of this family.  相似文献   
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Genotypic characteristics of two serotypes of Bartonella henselae   总被引:2,自引:0,他引:2       下载免费PDF全文
The study of 16S rRNA gene sequences of all isolates of Bartonella henselae obtained in our laboratory and others from human patients or cats has revealed two genotypes according to the sequence of the 16S rRNA gene. Two isolates of these genotypes have previously been related to two different serotypes, and lack of cross-protection of the two serotypes has been demonstrated in cats. We investigated the grouping of eight strains of B. henselae on the basis of 16S ribosomal DNA, 35-kDa protein, Pap 31 protein, and internal transcribed spacer (ITS) gene sequencing; sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles; and monoclonal antibody reactivity studies. Houston-1, 90-615, and SA2 strains showed the same patterns in SDS-PAGE, but they differed from the patterns of B. henselae isolates URBHLLY8, URBHLIE9, Cat6, Fizz, and CAL-1. Nine monoclonal antibodies derived from BALB/c mice immunized with B. henselae Houston-1 strain reacted only with strains Houston-1, 90-615, and SA2, and not with any other Bartonella strains. The two serogroups corresponded with two genotypes based on differences in the sequences of the genes encoding 16S rRNA, 35-kDa protein, and Pap 31 protein. Sequences of ITS genes were highly divergent among strains, as each had a unique sequence and the subdivision was not supported by DNA-DNA relatedness study. Study of 22 additional strains of B. henselae isolated from French bacteremic cats demonstrated that they all belong to one or the other of the proposed serotype or genotype.  相似文献   
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Meropenem (MEM) is a carbapenem antibiotic effective against infections caused by a variety of organisms. This study was conducted to evaluate MEM, which has not been previously used in the hospital, in parallel with some antimicrobial agents now in use, against organisms causing serious infections in the hospital. A total of 382 organisms isolated from blood cultures were included in the study. In the case of Bacteroides spp. and Burkholderia pseudomallei, organisms recovered from blood as well as from other sites were also included. In addition to MEM, 12 antimicrobial agents were tested against Gram-negative bacilli and seven against staphylococci. Antimicrobial susceptibility testing was carried out by the Kirby-Bauer disc diffusion technique based on the M2-A4 standard. The present paper demonstrates that meropenem, imipenem and ciprofloxacin are the most active antimicrobial agents against clinically important organisms causing serious infections in the hospital.  相似文献   
7.
Healthy blood donors from the city of Zagreb were checked for the presence of a nephrotoxic mycotoxin ochratoxin A (OTA) in the plasma. Samples of blood were collected in June, September, and December 1997, and March 1998, totalling 200 or 50 in each round. The concentrations of OTA were measured using high pressure liquid chromatography (HPLC) method (detection limit 0.2 ng OTA/ml of plasma). The frequency of OTA-positive samples (> 0.2 ng/ml of plasma) showed significant seasonal variation (P < 0.001). The frequency of OTA-positive samples was the highest in March (65%) and it gradually decreased towards December (12%). The high frequency of positive samples coincided with seasons favouring growth of moulds and production of toxins. The daily intake of OTA by healthy persons in Zagreb was estimated from the mean concentration of OTA in samples collected during the whole year (0.19 ng OTA/ml plasma). The estimated daily intake was 0.26 ng/kg b.w., that is, substantially below the tolerable daily intake proposed by World Health Organization (16.0 ng/kg b.w.).  相似文献   
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Optimization of an elastic tissue histochemical stain to enable clear, crisp visualization and quantification of pulmonary small vasculature is central to the histomorphologic quantitation of pulmonary vasculature wall thickness. To accomplish elastic tissue histochemical stain optimization, five histochemical elastin stains were compared to identify the internal and external elastic laminae of small arteries (50–100 μm in external diameter) to very small intra-acinar vessels (10–50 μm in external diameter) in rat lung tissue sections. The five elastin stains included: a modified Verhoeff’s elastin stain, Miller’s elastic van Gieson, and three modifications of the Miller’s stain. The Miller elastin stain is a progressive procedure that does not require a differentiation step, thus enabling consistency and reliability of staining from slide to slide. A modified Miller’s histochemical staining methodology successfully highlighted the pulmonary small caliber vasculature wall thickness. The modified method was technically easier and less time consuming to perform than regressive methods. To improve elastin-to-background contrast, modifications to the Miller’s stain included bypassing the nuclear staining and using a neutral red counterstain in place of the van Gieson counterstain, both of which greatly facilitated observer-assisted pulmonary vascular structure identification for histomorphometric quantitation.  相似文献   
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