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An Escherichia coli strain (serotype 0127a:H2) that had been isolated from a child with diarrhea in Thailand and that was negative for the virulence factors of the four categories of diarrheagenic E. coli (enterotoxigenic, enteropathogenic, enteroinvasive, and enterohemorrhagic) and that showed an aggregative pattern of adherence to HeLa cells was investigated for adherence to native or Formalin-fixed human and animal mucosa. The hemagglutinating activity and adherence ability of the bacteria were resistant to D-mannose and were strictly regulated by environmental conditions. Genetic data supported the close relation between the hemagglutinating activity and adherence ability. In accordance with the adherence pattern on tissue-cultured cells, the bacteria adhered to human and animal mucosa, as evidenced by a direct gold-labeling analysis. In human intestines, Formalin-fixed mucous coatings, epithelial cells of colonic mucosa, epithelial cells of ileal single lymphoid follicles and Peyer's patches, and the absorptive cells ofjejunal or ileal vili provided adherence targets. Adherence to M cells in the Peyer's patch-associated epithelium was also confirmed. The adherence levels to native jejunal or ileal human villi were low, as was the case with the corresponding Formalin-fixed villi. In human urinary tract, the superficial epithelial cells of both native and Formalin-fixed ureter provided striking adherence targets. In animal (porcine and rabbit) small intestines, the bacteria adhered to the native villi to a lesser extent than to the Formalin-fixed villi. The adherence levels were compared with those'of enterotoxigenic E. coli with colonization factor antigen (CFA)/I pili or CFA/II pili. The data suggested unique mucosa adherence characteristics of the enteroaggregative E. coli strain. The possibility of the adherence ability as a virulence factor was discussed. * Corresponding author. gative E. coli as a cause of pediatric diarrhea (2, 3). It has also been shown that enteroaggregative E. coli causes characteristic lesions in rabbit and rat ileal loops and possesses a 55to 65-MDa plasmid coding for the production of smooth lipopolysaccharide and pili; the plasmid also confers upon its host bacterial cells the ability to adhere to HEp-2 cells in an aggregative pattern (34). In previous experiments using Formalin-fixed or native human small intestinal or ureteral mucosa, we investigated the adherence sites and levels of bacterial enteropathogens Vibrio cholerae 01 (37, 38, 41), V. cholerae non-O1 (39), Vibrio parahaemolyticus (35, 42), and enterotoxigenic E. coli with colonization factor antigen (CFA)/I pili or CFAIII pili (36, 40). In this study, we used native or Formalin-fixed mucosa of human small intestines, human ureters, and animal (porcine and rabbit) small intestines to test 'the adherence ability of an enteroaggregative E. coli strain isolated from a child with diarrhea in Thailand. We found that the strain can adhere to both native and Formalin-fixed mucosa in an adherence manner that is very different ...

Paracoccidioidomycosis is a deep mycosis caused by the thermo-dependent dimorphic fungus Paracoccidioides brasiliensis and is prevalent in Latin American countries. We detected the species specific gp43 gene of P. brasiliensis by loop-mediated isothermal amplification (LAMP) in 22 clinical and seven armadillo-derived isolates. The amplified DNA appeared as a ladder with a specific banding pattern. The advantage of the LAMP method is speed; only 3 h were necessary for identification of the organism and diagnosis of the disease. We were also able to obtain positive results from DNA extracted from a paraffin-embedded tissue sample of paracoccidioidomycosis, suggesting that this method may achieve clinical application in the near future.

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