Role of Guinea Pigs (Cavia porcellus) Raised as Livestock in Ecuadorian Andes as Reservoirs of Zoonotic Yeasts.

Guinea pigs (Cavia porcellus) have been reared for centuries in the Andean region for ceremonial purposes or as the main ingredient of traditional foods. The animals are kept in close proximity of households and interact closely with humans; this also occurs in western countries, where guinea pigs are considered pets. Even though it is acknowledged that domestic animals carry pathogenic yeasts in their tissues and organs that can cause human diseases, almost nothing is known in the case of guinea pigs.

Climate change, melting cryosphere and frozen pathogens: Should we worry…?

Unlabelled: Permanently frozen environments (glaciers, permafrost) are considered as natural reservoirs of huge amounts of microorganisms, mostly dormant, including human pathogens. Due to global warming, which increases the rate of ice-melting, approximately 4 × 10 of these microorganisms are released annually from their frozen confinement and enter natural ecosystems, in close proximity to human settlements. Some years ago, the hypothesis was put forward that this massive release of potentially-pathogenic microbes-many of which disappeared from the face of the Earth thousands and even millions of years ago-could give rise to epidemics.

Perspectives for using glacial and periglacial microorganisms for plant growth promotion at low temperatures.

Even though they are among the most extreme environments in which life can develop, glaciers are colonized by metabolically active microbes, some of which thrive-in their own particular way-under the prevailing harsh conditions. Glacial or periglacial microbes are often psychrophiles since they are able to grow optimally at low temperatures. This ability has evolved through a series of adaptations, both molecular and physiological, some of which have been exploited by the biotechnological industry to develop useful products and processes.

Bioprospecting cold-adapted plant growth promoting microorganisms from mountain environments.

Mountain soils are challenging environments for all kinds of living things, including plants and microorganisms. Many cold-adapted microorganisms colonizing these extreme soils play important roles as promoters of plant growth and development; for that reason, they are called collectively plant growth-promoting microorganisms (PGPM). Even though there is seldom doubt concerning the usefulness of PGPM to develop eco-friendly bioinoculants, including biofertilizers and biocontrollers, a series of aspects need to be addressed in order to make this technology field-applicable.

Diversity of culturable bacteria recovered from Pico Bolívar's glacial and subglacial environments, at 4950 m, in Venezuelan tropical Andes.

Even though tropical glaciers are retreating rapidly and many will disappear in the next few years, their microbial diversity remains to be studied in depth. In this paper we report on the biodiversity of the culturable fraction of bacteria colonizing Pico Bolívar's glacier ice and subglacial meltwaters, at ∼4950 m in the Venezuelan Andean Mountains. Microbial cells of diverse morphologies and exhibiting uncompromised membranes were present at densities ranging from 1.

Bioprospecting glacial ice for plant growth promoting bacteria.

Glaciers harbor a wide diversity of microorganisms, metabolically versatile, highly tolerant to multiple environmental stresses and potentially useful for biotechnological purposes. Among these, we hypothesized the presence of bacteria able to exhibit well-known plant growth promoting traits (PGP). These kinds of bacteria have been employed for the development of commercial biofertilizers; unfortunately, these biotechnological products have proven ineffective in colder climates, like the ones prevailing in mountainous ecosystems.

Bacteria recovered from a high-altitude, tropical glacier in Venezuelan Andes.

Glacial-ice microorganisms are intensively studied world-wide for a number of reasons, including their psychrophilic lifestyle, their usefulness in biotechnology procedures and their relationship with the search of life outside our planet. However, because of the difficulties for accessing and working at altitudes of >5.000 m above sea level, tropical glaciers have received much less attention than their arctic and antarctic counterparts.

Characterization of the mineral phosphate-solubilizing activity of Pantoea agglomerans MMB051 isolated from an iron-rich soil in southeastern Venezuela (Bolívar State).

The mineral phosphate-solubilizing (MPS) activity of a Pantoea agglomerans strain, namely MMB051, isolated from an iron-rich, acidic soil near Ciudad Piar (Bolívar State, Venezuela), was characterized on a chemically defined medium (NBRIP). Various insoluble inorganic phosphates, including tri-calcium phosphate [Ca(3)(PO(4))(2)], iron phosphate (FePO(4)), aluminum phosphate (AlPO(4)), and Rock Phosphate (RP) were tested as sole sources of P for bacterial growth. Solubilization of Ca(3)(PO(4))(2) was very efficient and depended on acidification of the external milieu when MMB051 cells were grown in the presence of glucose.

Mercury resistance in bacterial strains isolated from tailing ponds in a gold mining area near El Callao (Bolívar State, Venezuela).

Bacterial resistance to mercury (Hg) was investigated in strains isolated from Hg-contaminated tailing ponds located in the gold mining area of El Callao (Bolívar State, Venezuela). High frequencies of resistance were detected to both inorganic-Hg and organomercurials among these strains. A broad range of resistance levels was observed when determining minimal inhibitory concentrations of Hg(2+).

Onchocerca-Simulium complexes in Venezuela: can human onchocerciasis spread outside its present endemic areas?

The compatibility between sympatric and allopatric combinations of Onchocerca volvulus-anthropophilic species of Simulium was studied in the north-eastern focus of human onchocerciasis as well as in a densely populated locality of the Amazonas State in Venezuela. The objectives were to test the conjecture that local adaptation exists between the parasite and its vectors (the Onchocerca-Simulium complex hypothesis), and assess the possibility of the infection spreading from its present distributional range. For the homologous combination, O.

Risk factors associated with human cystic echinococcosis in Florida, Uruguay: results of a mass screening study using ultrasound and serology.

Sonographic evidence of asymptomatic Echinococcus granulosus lesions in the liver was found in 156 of 9,515 persons in the Department of Florida, Uruguay. The sensitivity of ELISA and latex agglutination serology compared with ultrasound was 47.6% and 28.

Principles of the surgical approach in human liver cystic echinococcosis.

Ultrasonography (USG) has recently contributed much to the diagnostic of hepatic cystic echinococcosis (CE). The use of portable ultrasonograph allowed us to perform a community survey among 9482 people living in a high risk area for CE in the Florida Department (Uruguay). Positive USG results were found in 123 asymptomatic patients.

Specific detection of human antibodies to Onchocerca volvulus.

Specific diagnosis of antibodies to Onchocerca was achieved through (1) the construction of direct and indirect ELISA systems, and (2) restricting ELISA assays to the IgG4 class. The direct ELISA was based on the isolation of a surface derived, low molecular weight surface antigen preparation containing two main antigens (M. wt.

Susceptibility of Plasmodium falciparum strains to chloroquine and mefloquine in the Amazonas Federal Territory of Venezuela.

The susceptibilities of 27 Plasmodium falciparum strains to chloroquine and mefloquine were studied in the area of Puerto Ayacucho, Amazonas Federal Territory of Venezuela, to determine their levels of resistance in vivo and in vitro. 50% of these strains showed chloroquine resistance in vivo. No grade III chloroquine resistance was found.

Sporotrichosis in the Orinoco river basin of Venezuela and Colombia.

Six cases of sporotrichosis from the Orinoco river basin of Venezuela and Colombia are described; two are of the localized cutaneous type and four are lymphocutaneous. Diagnosis was based on the patient's clinical history and mycological culture. Epidemiology and distinctive cultural habits of the patients are discussed in connection with disease etiology.

The vectoral role of several blackfly species (Diptera: Simuliidae) in relation to human onchocerciasis in the Sierra Parima and Upper Orinoco regions of Venezuela.

Experimental and natural infections with Onchocerca volvulus were studied in several anthropophilic blackfly species present in the endemic area of the Upper Orinoco region of Venezuela. When fed on four different Yanomami volunteers in the Sierra Parima, the total infection rate was 31.4% for Simulium guianense in comparison with 7.

Morphological differences between Venezuelan and African microfilariae of Onchocerca volvulus.

Comparative morphological and biometric characteristics of microfilariae of Onchocerca gutturosa and O. volvulus from different geographical areas (Upper Orinoco, Venezuela; Togo; Liberia) were assessed. "Stepwise" discriminant analysis and Mahalanobis estimators were applied to measure distance between populations.

Parasite antigens are present in breast milk of women infected with Onchocerca volvulus.

We used a noncompetitive two-site ELISA with 5 monoclonal antibodies to determine whether parasite antigens are present in breast milk from women infected with Onchocerca volvulus. Seven out of 13 available milk samples contained significant amounts of filarial antigens. Antigen indices in milk correlated with levels of microfilarodermia (Rs = 0.

Studies on a filarial antigen with collagenase activity.

We examined the ability of two filarial species, Onchocerca volvulus and Brugia malayi, to solubilize collagen molecules from native collagen fibrils. Collagenolytic activity was detected in extracts of adult worms, in living microfilariae of O. volvulus and in live infective larvae and adult female worms of B.

Experimental and natural infection of Simulium sanchezi by Mansonella ozzardi in the Middle Orinoco region of Venezuela.

Experimental and natural infections of Simulium sanchezi by Mansonella ozzardi were studied in the area of Síquita, Territorio Federal Amazonas, Venezuela. The microfilariae developed synchronously in the blackflies, reaching stage L3 in seven to eight days at temperatures between 23 degrees and 27 degrees C. Larvae in different stages of development, including infective forms, were found in 0.

Onchocerciasis in Venezuela: prevalence of microfilaraemia in Amerindians and morphological characteristics of the microfilariae from the Upper Orinoco Focus.

Data are presented on microfilaraemia in 191 Yanomami Amerindians from two areas of Venezuela's Upper Orinoco Basin, where an endemic focus of onchocerciasis has been recently detected. Onchocerca microfilariae were found in the blood of 12.6% of the persons examined.

Development of Onchocerca volvulus larvae in Simulium pintoi in the Amazonas region of Venezuela.

The intake and development of Onchocerca volvulus in Simulium pintoi from the Parima mountain region of the Federal Territory of Amazonas in Venezuela, were studied experimentally. When wild females fed on the lower half of the legs and lower third of the back of an onchocerciasis patient harboring 23 and 264 microfilariae per skin snip, respectively, at each site, an average (median) of 14 (range, 1-77) and 245 (range, 58-495) microfilariae was ingested. However, within 24 hours of microfilarial ingestion a mortality of 47% (16/34 flies) was observed in the group of flies which fed on the back, as compared with 2% (2/101 flies) in the other group which fed on the legs.

Acid phosphatase patterns in microfilariae of Onchocerca volvulus s.l. from the Upper Orinoco Basin, Venezuela.

The patterns of acid phosphatase in strains of Onchocerca volvulus s.l. which parasitize an Amerindian population (Yanomami) in Venezuela's Upper Orinoco Basin were examined by using the naphthol AS-TR phosphate method.

Onchocerca volvulus: detection of circulating antigen by monoclonal antibodies in human onchocerciasis.

A monoclonal antibody of the IgM class recognizing Onchocerca volvulus circulating antigen (COA) was obtained. This monoclonal antibody was used in a radioimmunoprecipitation-PEG assay (RIPEGA) to detect circulating antigen in onchocerciasis patients' sera. COA could be detected in 63 (80%) of the 79 African patient sera tested, and in 126 (76%) of the 164 Indian (Venezuela) sera studied.