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Borreliaceae is a family of the phylum Spirochaetales and includes two genera, Borrelia and Cristispira genus. Borrelia genus is divided into three groups, namely Lyme group (LG), Echidna‐Reptile group (REPG) and Relapsing Fever group (RFG). All Borrelia species have an obligate parasitic lifestyle, as they depend on their hosts for most of their nutritional needs. Borreliæ are transmitted among vertebrate hosts by arthropod vectors (ticks and lice). Transtadial transmission within their carriers occurs for the Borreliæ RF Group, while this does not (or rarely occurs) for the Borreliæ Lyme Group. Phylogenetic data demonstrated that these two groups are genetically similar but distinct, forming independent clades sharing a common ancestor. In nature, the vectors of LB belong to the genus Ixodes spp. frequently found in the Northern Hemisphere, while the vectors of RF are usually the soft-ticks (Ornithodoros spp.). Borreliae share a unique genomic structure consisting of a single highly conserved linear chromosome and several linear and circular extrachromosomal plasmids which can vary widely between strains. In addition to Lyme and RF borreliosis, an intermediate group, called Echidna-Reptile borreliosis, has recently been identified. Lyme disease (LD) is caused by the spirochæte Borrelia burgdorferi sensu lato (s.l.) and transmitted to humans by the bite of a hard tick of the genus Ixodes, and LD reservoir are usually small rodents. LD is present in America, Eurasia, Africa, while its presence in Australia is not yet well documented. Not all Borreliæ Lyme Groups cause this disease in humans. Of the 23 Borreliæ burgdorferi s.l. currently known only 9 have been identified in human infection, namely Borrelia burgdorferi sensu stricto, B. afzelii, B. bavarensis, B. bissettii, B. garinii, B. lusitaniae, B. spielmani, B. valaisiana, and B. mayonii. LD is an organotropic infection, but there is also a spirochætemic form, caused by Borrelia mayonii, which gives fever similarly to the Borreliosis RF Group. A third variant of LD is Baggio-Yoshinari Syndrome (BYS), which is transmitted by another hard tick, Amblyomma cajennense. This Borrelia has not been isolated in culture, therefore its membership in the Lyme Group is not yet proven. All three of these Sub-Groups can manifest early with erythema migrans. Clinical features of LD are wide and variable, with clinical manifestations linked to distinct tissue tropisms of specific Borrelia burgdorferi s.l. genospecies. The early infection is localized and, in the absence of treatment, the spirochete can spread. The organs most frequently involved are skin, joints, muscles, nervous system, heart and eyes. B. burgdorferi s.s. is more often associated with Lyme arthritis, Borrelia garinii with neuroborreliosis and B. afzelii with acrodermatitis chronica atrophicans.

Leptospires, the agents of leptospirosis, exert tropism for the central nervous system, in the course of mammal infection. We evaluated the interaction between murine microglial cells and strains of pathogenic L. interrogans leptospires and non-pathogenic L. biflexa leptospires, mainly by flow cytometric assays. In the absence of opsonic conditions microglia are capable of ingesting--even quite slowly--the spirochetes and killing the non-pathogenic strain. The adhesion to microglia, which is quick and relevant for all the strains, does not involve the CR3 integrin receptor. These findings suggest that the murine microglia--in non opsonic conditions in vitro--do not effectively clear the pathogenic leptospires.

Two new dammarane saponins identified as jujubogenin 3-O-alpha-l-arabinofuranosyl(1-->2)-[beta-d-glucopyranosyl(1-->6) beta-d-glucopyranosyl(1-->3)]-alpha-l-arabinopyranoside (2) and jujubogenin 3-O-alpha-l-arabinofuranosyl(1-->2)-[6-O-[3-hydroxy-3-methylglutaryl]-beta-d-glucopyranosyl(1-->3)]-alpha-l-arabinopyranoside (3) and a new lupane saponin, 3beta-hydroxylup-20(29)-en-27,28-dioic acid 28-O-beta-d-glucopyranosyl(1-->2)-[beta-d-xylopyranosyl(1-->3)]-beta-d-xylopyranosyl(1-->2)-beta-d-glucopyranoside ester (5), along with the known jujubogenin 3-O-alpha-l-arabinofuranosyl(1-->2)-[beta-d-glucopyranosyl(1-->3)]-alpha-l-arabinopyranoside (1) and 3beta-hydroxylup-20(29)-ene-27,28-dioic acid (4), were isolated from the methanol extract of the stems of Anomospermum grandifolium. The structures of the new compounds were established by spectral analysis. Antimicrobial activity screening of compounds 1-3 revealed antifungal properties against C. albicans ATCC 3153 for compounds 2 and 3. The antibacterial and antifungal activities of the petroleum ether, chloroform, and methanol extracts of A. grandifolium stems were also evaluated.

Actualmente se están buscando nuevas alternativas energéticas a partir de biomasa, recursos renovables y desechos agroindustriales, para desarrollar nuevas tecnologías y procesos en la obtención de biocombustibles. El objetivo fue obtener celulosa y bio-etanol del bagazo de piña (desecho agrícola). El aprovechamiento de este bagazo evitará el consumo de cultivos destinados a la alimentación, evitando el uso excesivo de tierras y el empleo de residuos orgánicos agroindustriales. Además, el producto obtenido tiene un valor agregado y podría convertirse en un beneficio para los productores de piña. La finalidad fue estudiar un proceso para extraer celulosa del bagazo de piña, y mediante hidrólisis ácida de celulosa y bagazo se obtuvo glucosa. Esta glucosa se neutralizó a pH de 5 y se realizó la fermentación en un medio anaeróbico, utilizando el microorganismo Saccharomyces cerevisiae, variando tiempos de fermentación (36, 40, 48 y 72 h) y manteniendo la temperatura a 30ºC. La celulosa obtenida presentó una conversión del 60% y mediante FTIR se corroboró que la celulosa fue tipo II. Se obtuvo bio-etanol mediante destilación, presentando un rendimiento del 35% con bagazo y del 57% con celulosa con un tiempo de fermentación de 48 y 72 h, respectivamente.

INFECT IMMUN

Rationale. The prevalence of Borrelia burgdorferi in Ixodes ricinus ticks is one indicator for identifying the risk of infection in a given territory. Methods. Two PCR procedures were developed to detect B. burgdorferi infection in Ixodes ricinus nymphs. For the first method we used primers to amplify a fragment of the flagellin gene (fla) specific for B. burgdorferi sensu lato. In the second, we employed species-specific oligonucleotides directed against 16S rRNA which were able to specifically identify the genospecies of B. burgdorferi sensu stricto, B. garinii and B. afzelii, and another set for B. burgdoroferi sensu lato. Results. No amplification product was detected in uninfected control ticks whereas both techniques gave positive amplification for B. burgdorferi sensu lato in 73.8-79.0% of the field-collected ticks. The two PCR procedures were in agreement in identifying B. burgdorferi sensu lato infection. The use of flagellin primers seemed more sensitive than the oligonucleotide-based approach but it was also more complex for processing a large number of tick samples. The most prevalent species were B. burgdorferi sensu stricto and B. garinii and co-infected the same tick in 25% of PCR-positive samples. Only a few ticks proved to be infected by B. afzelii. We believe that use of PCR is accurate for prevalence studies. Moreover, it provides information about the geno-species of B. burgdorferi circulating in the tick vectors.