Abstract. A seroprevalence study for IgG antibodies against spotted fever group (SFGR) and typhus group (TGR) Rickettsia among humans and domestic pets was conducted in the city of Iquitos, located in the Amazon basin of Peru. Of 1,195 human sera analyzed, 521 (43.6%) and 123 (10.3%) were positive for SFGR and TGR antibodies, respectively. District of residence and participant age were associated with antibody positivity for both groups, whereas rodent sightings in the home were associated with TGR antibody positivity. Of the 71 canines tested, 42 (59.2%) were positive for SFGR antibodies, and two (2.8%) were positive for TGR antibodies; one active SFGR infection was detected by polymerase chain reaction. An uncharacterized SFGR species was detected in 95.9% (71/74) of Ctenocephalides felis pools collected from domestic pets. These data suggest that rickettsial transmission is widespread in Iquitos. Rickettsia species should be further explored as potential causes of acute febrile illnesses in the region.
Mucolipidosis II (ML II) and mucolipidosis III (ML III) are diseases in which the activity of the uridine diphosphate (UDP)-N-acetylglucosamine:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase) is absent or reduced, respectively. In the absence of mannose phosphorylation, trafficking of lysosomal hydrolases to the lysosome is impaired. In these diseases, mistargeted lysosomal hydrolases are secreted into the blood, resulting in lysosomal deficiency of many hydrolases and a storage-disease phenotype. GlcNAc-phosphotransferase is a multimeric transmembrane enzyme composed of three subunits (alpha, beta and gamma) encoded by two genes -GNPTAB and GNPTG. Defects in GNPTAB result in ML II and III whereas mutations in GNPTG were only found in ML III patients. We have performed a molecular analysis of the GNPTAB and GNPTG genes in 13 mucolipidosis II and III patients (10 Portuguese, one Finnish, one Spanish of Arab origin and one Indian). Mutations were identified by the study of both cDNA and gDNA. The GNPTAB and GNPTG mRNA expressions were determined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). The study led to the identification of 11 different mutations. Eight of these mutations are novel, six in the GNPTAB gene [c.121delG (V41FfsX42), c.440delC (A147AfsX5), c.2249_50insA (N750KfsX8), c.242G>T (W81L), c.1208T>C (I403T) and c.1999G>T (p.E667X)] and two in the GNPTG gene [c.610-1G>T and c.639delT (F213LfsX7)]. With regard to the mRNA expression studies, the values obtained by qRT-PCR indicate the possible existence of feedback regulation mechanisms between alpha/beta and the gamma subunits.
Using a large, passive, clinic-based surveillance program in Iquitos, Peru, we characterized the prevalence of rickettsial infections among undifferentiated febrile cases and obtained evidence of pathogen transmission in potential domestic reservoir contacts and their ectoparasites. Blood specimens from humans and animals were assayed for spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) by ELISA and/or PCR; ectoparasites were screened by PCR. Logistic regression was used to determine associations between patient history, demographic characteristics of participants and symptoms, clinical findings and outcome of rickettsial infection. Of the 2,054 enrolled participants, almost 2% showed evidence of seroconversion or a 4-fold rise in antibody titers specific for rickettsiae between acute and convalescent blood samples. Of 190 fleas (Ctenocephalides felis) and 60 ticks (Rhipicephalus sanguineus) tested, 185 (97.4%) and 3 (5%), respectively, were positive for Rickettsia spp. Candidatus Rickettsia asemboensis was identified in 100% and 33% of the fleas and ticks tested, respectively. Collectively, our serologic data indicates that human pathogenic SFGR are present in the Peruvian Amazon and pose a significant risk of infection to individuals exposed to wild, domestic and peri-domestic animals and their ectoparasites.
The accurate identification of taxa of Aotus is essential for 1) the development of precise biomedical assays, 2) the determination of potential illegal traffic of this genus, and 3) conservation. Although many studies have contributed to what we know about the phylogenetics of Aotus, none used a sufficiently large number of samples to clarify its complexity. To address this need, we sequenced 696 base pairs of the mitochondrial cytochrome-oxidase II gene (mtCOII) in 69 specimens of 7 taxa of Aotus. We also analyzed 8 microsatellite loci in 136 individuals of 6 taxa. In contrast to previous studies, we sampled only wild individuals and have a precise geographical origin for each one. The mtDNA results showed that: 1) the northern gray-necked group of Aotus is genetically more homogeneous than the polyphyletic red-necked group of Aotus; 2) the ancestors of Aotus vociferans seem to be the original species candidate for the current Aotus; 3) Aotus azarae azarae and A. a. boliviensis are the most differentiated taxa, likely a result of extreme genetic drift during stasipatric speciation; 4) the first genetic splits found among taxa of Aotus occurred during the Pliocene (or even Miocene) while the most recent ones happened during the Pleistocene, when forest refugia may have played an important role in speciation. The mean number of microsatellite alleles was 3–5.33 alleles per locus. We found some private alleles that could be useful in helping to identify illegal trade, although a larger sample size is needed to ensure that these alleles are really private to the relevant taxa. These new findings increase our understanding of the phylogeny of Aotus and the level of genetic diversity within different taxa of Aotus.Fil: Ruiz García, Manuel. Pontificia Universidad Javeriana; ColombiaFil: Vásquez, Catalina. Pontificia Universidad Javeriana; ColombiaFil: Camargo Acosta, Emily Yineth. Pontificia Universidad Javeriana; Colombia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiarida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiarida; ArgentinaFil: Leguizamón, Norberto. Secretaría Distrital Ambiental; ColombiaFil: Gálvez, Hugo. Instituto Veterinario de Investigaciones Tropicales y de Altura. Estación Experimental; Perú. Universidad Nacional Mayor de San Marcos; PerúFil: Vallejo, Adriana. Pontificia Universidad Javeriana; ColombiaFil: Pinedo, Myreya. Pontificia Universidad Javeriana; ColombiaFil: Castellanos Mora, Luisa. Fundación Omacha; ColombiaFil: Shostell, Joseph. University of Pennsylvania; Estados UnidosFil: Alvarez, Diana. Pontificia Universidad Javeriana; Colombi
Some previous genetic studies have been performed to resolve the molecular phylogenetics of the squirrel monkeys (Saimiri). However, these studies did not show consensus in how many taxa are within this genus and what the relationships among them are. For this reason, we sequenced 2,237 base pairs of the mt COI and COII genes in 218 Saimiri individuals. All, less 12 S. sciureus sciureus from French Guyana, were sampled in the wild. These samples represented all the living Saimiri taxa recognized. There were four main findings of this study. (1) Our analysis detected 17 different Saimiri groups: albigena, cassiquiarensis, five polyphyletic macrodon groups, three polyphyletic ustus groups, sciureus, collinsi, boliviensis, peruviensis, vanzolinii, oerstedii and citrinellus. Four different phylogenetic trees showed the Central American squirrel monkey (S. oerstedii) as the most differentiated taxon. In contrast, albigena was indicated to be the most recent taxon. (2) There was extensive hybridization and/or historical introgression among albigena, different macrodon groups, peruviensis, sciureus and collinsi. (3) Different tests showed that our maximum likelihood tree was consistent with two species of Saimiri: S. oerstedii and S. sciureus. If no cases of hybridization were detected implicating S. vanzolinii, this could be a third recognized species. (4) We also estimated that the first temporal splits within this genus occurred around 1.4-1.6 million years ago, which indicates that the temporal split events within Saimiri were correlated with Pleistocene climatic changes. If the biological species concept is applied because, in this case, it is operative due to observed hybridization in the wild, the number of species within this genus is probably more limited than recently proposed by other authors. The Pleistocene was the fundamental epoch when the mitochondrial Saimiri diversification process occurred.
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