Coccidioides posadasii is a fungal respiratory pathogen which is responsible for recurrent epidemics of San Joaquin Valley fever (coccidioidomycosis) in desert regions of the southwestern United States. Numerous studies have revealed that the cell wall of the parasitic phase of the fungus is a reservoir of immunoreactive macromolecules and a potential source of a vaccine against this mycosis. A 495-bp fragment of a C. posadasii gene which encodes a putative wall-associated, glycosylphosphatidylinositol (GPI)-anchored ␤-1,3-glucanosyltransferase was identified by computational analysis of the partially sequenced genome of this pathogen. The translated, full-length gene (GEL1) showed high sequence homology to a reported ␤-1,3-glucanosyltransferase of Aspergillus fumigatus (70% identity, 90% similarity) and was selected for further study. The GEL1 mRNA of C. posadasii was detected at the highest level during the endosporulation stage of the parasitic cycle, and the mature protein was immunolocalized to the surface of endospores. BALB/c or C57BL/6 mice were immunized subcutaneously with the bacterium-expressed recombinant protein (rGel1p) to evaluate its protective efficacy against a lethal challenge of C. posadasii by either the intraperitoneal or intranasal route. In both cases, rGel1p-immune mice infected with the pathogen showed a significant reduction in fungal burden and increased survival compared to nonimmune mice. The recombinant ␤-1,3-glucanosyltransferase is a valuable addition to an arsenal of immunoreactive proteins which could be incorporated into a human vaccine against coccidioidomycosis.

Aim: The study was conducted to determine the prevalence of gastrointestinal (GI) parasites in cattle and sheep from three municipalities in the Colombian Northeastern Mountain. Materials and Methods: Overall, 200 fecal samples were collected directly from the rectum in cattle and sheep. The presence of helminths eggs and coccidial oocysts in fecal samples was detected using McMaster and Dennis techniques. Identification of eggs or oocysts was done on the basis of morphology and size of the eggs or oocysts. Results: The global prevalence of GI parasites was 56.3%. Regarding the prevalence by municipalities, there was no statistical association (p>0.05), indicating that the prevalence was similar in the three municipalities. The prevalence of parasitic infection was higher in sheep (63%) as compared to that of cattle (50.5%), but the difference was nonsignificant (p>0.05). The most prevalent parasites were Eimeria spp., Fasciola hepatica, and Strongylida order. Regarding the results for Eimeria spp., different degrees of positivity were observed, but there was no statistical association (p>0.05) with respect to the age group. Likewise, there was no statistical association (p>0.05) between the prevalence for Strongylida order and F. hepatica with respect to the age group. Conclusion: Cattle and sheep in Colombian Northeastern Mountain were infected with helminths and coccidia. The prevalence values of GI parasites were moderate in both species warranting treatment. The presence of F. hepatica represents a risk factor to health public. Future studies are required to evaluate the parasitic dynamics throughout the year and the impact on animal production.

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Coccidioides posadasii is a dimorphic fungal pathogen which grows as a filamentous saprobe in the soil and multicellular parasitic form in host lung tissue. Studies of gene expression profiles during saprobic and parasitic phase development can provide clues about morphogenetic regulation and may lead to the discovery of molecular targets for novel antifungal drugs. Suppression-subtractive hybridization (SSH) and quantitative real-time polymerase chain reaction (QRT-PCR) were used to identify and quantify differential gene expression during in vitro growth of Coccidioides. DNA fragments obtained from the subtraction of cDNA pools derived from the saprobic and parasitic phase RNA preparations were each cloned into an appropriate vector and subjected to sequence analysis. Semi-quantitative, reverse transcription polymerase chain reaction (RT-PCR) experiments were first conducted to assess whether these inserts represented differentially expressed genes. Nucleotide sequences of the partial and full-length genes selected by RT-PCR were obtained by genome walking and rapid amplification of cDNA ends (RACE) methods. QRT-PCR analysis of the expression of these genes during saprobic and parasitic cell growth was then conducted using DNA standard curves normalized to a constitutively expressed control gene. Four C. posadasii genes whose expression is essentially restricted to the parasitic cycle were discovered using this approach. These genes include homologues of OPS1 (encodes opsin-related protein), MDR1 (multidrug resistance protein), ALDR1 (aldehyde reductase), and PSP1 (hypothetical lipid transporter/flippase protein). The combined applications of SSH and QRT-PCR permit global analysis of gene expression patterns in C. posadasii.

Backyard pigs have been associated with poor sanitary conditions and the development of parasitic diseases, often causing public health and food safety problems. Therefore, the aim of this study was to determine the prevalence and risk factors for gastrointestinal parasites in backyard pigs. 279 animals were sampled from thirty-two backyard pig farms located in the Bucaramanga, Floridablanca, Giron and Piedecuesta municipalities, from Bucaramanga Metropolitan Area, Colombia. Fecal samples were taken directly from the rectum and processed by four coprological techniques. The overall prevalence of gastrointestinal parasites was 91%, being the highest values for Balantidium coli and Eimeria sp. Regarding the prevalence by municipalities, there was no statistical association (p ≥ 0.05) indicating that the prevalence was similar in the region under study. Floridablanca municipality, free-ranging pigs, access to latrines, and consumption of spring water showed to be a risk factor for nematodes, while Giron municipality, pigs > 7 months of age and access to latrines, increased infection risk for coccidian. We concluded that there is a high prevalence of gastrointestinal parasites in backyard pigs from the Bucaramanga Metropolitan Area, and that it could be controlled by improving management practices and farm facilities.