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ABSTRACTThe aim of this work was to document molecular epidemiology of Rasamsonia argillaceaspecies complex isolates from cystic fibrosis (CF) patients. In this work, 116 isolates belonging to this species complex and collected from 26 CF patients and one patient with chronic granulomatous disease were characterized using PCR amplification assays of repetitive DNA sequences and electrophoretic separation of amplicons (rep-PCR). Data revealed a clustering consistent with molecular species identification. A single species was recovered from most patients. Rasamsonia aegroticolawas the most common species, followed by R. argillacea sensu strictoand R. piperina, while R. eburneawas not identified. Of 29 genotypes, 7 were shared by distinct patients while 22 were patient specific. In each clinical sample, most isolates exhibited an identical genotype. Genotyping of isolates recovered from sequential samples from the same patient confirmed the capability of R. aegroticolaand R. argillaceaisolates to chronically colonize the airways. A unique genotype was recovered from two siblings during a 6-month period. In the other cases, a largely dominant genotype was detected. Present results which support the use of rep-PCR for both identification and genotyping for the R. argillaceaspecies complex provide the first molecular evidence of chronic airway colonization by these fungi in CF patients.

This study aimed to identify chemical components and evaluate the antioxidant and antibacterial activities of ethanolic and dichloromethane extracts of Ammi visnaga(L.). Both extracts contained flavonoids, coumarins, and glycosides, with the ethanolic extract also exhibiting tannins and reducing sugars. Qualitative HPLC/UV-ESI-MS analysis revealed abundant polyphenols, particularly flavonoids and furanochromones, such as rhamnazin, kaempferol, rhamnetin, khellin, visnagin, khellinin, and khellol. Antimicrobial activity against Gram-positive and Gram-negative bacteria was assessed, with Klebsiella pneumoniaeshowing sensitivity to the ethanol extract, resulting in a 9mm inhibition zone. The dichloromethane extract exhibited a 9mm inhibition zone against Acinetobacter baumannii, with a minimum inhibitory concentration (MIC) of 10µL/mL for both extracts and all susceptible strains. Antioxidant activity, measured by radical DPPH∙ radical reduction test revealed significant reducing power in the ethanolic extract, with an IC50 = 1.383 ± 0.069 mg/mL, compared to IC50 = 0.095 ± 0.009 mg/mL for ascorbic acid, used as reference.

ABSTRACTUsually a saprophyte, Scedosporium apiospermumoften colonizes the respiratory tracts of patients with cystic fibrosis (CF). In order to improve our understanding of the molecular epidemiology of the airway colonization, 129 sequential and multiple isolates collected from January 1998 to March 1999 from nine CF patients monitored in three hospitals in France were typed by random amplification of polymorphic DNA with primers GC70, UBC-701, and UBC-703. Among these primers, UBC-703 was the most discriminating, allowing the differentiation of 14 genotypes. Combining the results obtained with this three-primer set resulted in the differentiation of 16 genotypes. No common genotype was found among the different patients, and no clustering according to geographic origin of the isolates was seen. In addition, five of the patients were colonized by a single genotype. The others usually exhibited a predominant genotype accompanied by one or two others, which were found occasionally and were genetically close to the predominant genotype. Thus, our study demonstrates the persistence of the fungus despite antifungal treatments and therefore reinforces the need for the development of new antifungals that are more efficient against this species.

Zouhair, R., Corradini, P., Defontaine A. & Hallet, J. N.: RAPD markers for genetic differentiation of species within Polytrichum(Polytrichaceae, Musci): a preliminary survey – Taxon 49: 217–229. 2000. – ISSN 0040‐0262. A combination of morphological data and RAPD markers were analysed using thirty colonies from Brittany (France) in six taxa of Polytrichum: P. commune, P. c.var. perigoniale, P. formosum, P. juniperinum, P. piliferum,and P. strictum.Ten primers selected for the RAPD study produced 166 polymorphic markers useful for cluster analysis. The Jaccard index of similarity was high within and among taxa and varied from 0.56 between P. communeand P. formosumto 0.89 between P. formosumand P. juniperinum.For the morphological study, shape of terminal cells of the green lamellae covering the upper surface of leaves allowed differentiation of taxa. In P. communevar. perigonialethese cells were narrower and less deeply notched than in P. commune.The diameter of leaves was scored for many individuals of the six taxa and revealed a sexual dimorphism for size. Female plants have a significantly larger leaf rosette diameter than male plants. Morphological results are largely consistent with RAPD data. However, the high level of genetic differences of P. c.var. perigonialeand P. strictumwith other taxa demonstrates the potential of molecular and genetic data in phylogenetic analysis among closely related taxa. The cluster analysis divides the taxa into two groups: (1) P. commune, P. formosumand P. c.var. perigoniale;and (2) P. juniperinum, P. piliferum,and P. strictum.The results do not support splitting the genus into Polytrichumand Polytrichastrumnor the possibility of hybrid origin of P. c. var. perigonialebetween P. communeand P. formosum.