Browsing by Autor "Susana Revollo"

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[A new case of autochthonous visceral leishmaniasis in Bolivia].
(National Institutes of Health, 1991) L. Dimier-David; A. Inofuentes; María Hernández Carrasco; Catherine David; Franklin Vargas; Susana Revollo; Dedet Jp
A sixth autochthonous case of visceral leishmaniasis is reported in Bolivia. It is also the fourth case detected in the Yungas Valley (Department of La Paz) confirming the long-term existence of the disease in this area where cases of canine leishmaniasis and natural infestation of the phlebotomine sandfly, Lutzomyia longipalpis, were previously reported.
A new subhaplogroup of native American Y-Chromosomes from the Andes
(Wiley, 2011) Marilza S. Jota; Daniela R. Lacerda; José R. Sandoval; Pedro Paulo Vieira; Simone S. Santos-Lopes; Rafael Bisso‐Machado; Vanessa Rodrigues Paixão‐Côrtes; Susana Revollo; César Paz‐y‐Miño; Ricardo Fujita
The human Y chromosome contains highly informative markers for making historical inferences about the pre-Columbian peopling of Americas. However, the scarcity of these markers has limited its use in the inference of shared ancestry and past migrations relevant to the origin of the culturally and biologically diverse Native Americans. To identify new single nucleotide polymorphisms (SNPs) and increase the phylogenetic resolution of the major haplogroup Q found in the Americas, we have performed a search for new polymorphisms based on sequencing divergent Y chromosomes identified by microsatellite haplotype analysis. Using this approach, a new Y-SNP (SA01) has been identified in the Andean populations of South America, allowing for the detection of a new sublineage of Q1a3a. This sublineage displays a less complex phylogeographic network of associated microsatellites and more restricted geographic occurrence, and is given the designation Q1a3a4. This result indicates that our approach can be successfully used to identify sublineages of interest in a specific region that allow the investigation of particular histories of human populations.
Chagas’ disease diagnosis: a multicentric evaluation of Chagas Stat-Pak, a rapid immunochromatographic assay with recombinant proteins of Trypanosoma cruzi
(Elsevier BV, 2003) Alejandro O. Luquetti; Carlos Ponce; Elisa Ponce; Javan Esfandiari; Alejandro G. Schijman; Susana Revollo; Néstor Áñez; Bianca Zingales; Rafael Ramgel-Aldao; Antonio G. González
Divergent Mitochondrial Antioxidant Activities and Lung Alveolar Architecture in the Lungs of Rats and Mice at High Altitude
(Frontiers Media, 2018) Alexandra Jochmans‐Lemoine; Susana Revollo; Gabriella Villalpando; I. Valverde; Marcelino Gonzales; Sofien Laouafa; Jorge Soliz; Vincent Joseph
Compared with mice, adult rats living at 3,600 m above sea level (SL-La Paz, Bolivia) have high hematocrit, signs of pulmonary hypertension, and low lung volume with reduced alveolar surface area. This phenotype is associated with chronic mountain sickness in humans living at high altitude (HA). We tested the hypothesis that this phenotype is associated with impaired gas exchange and oxidative stress in the lungs. We used rats and mice (3 months old) living at HA (La Paz) and SL (Quebec City, Canada) to measure arterial oxygen saturation under graded levels of hypoxia (by pulse oximetry), the alveolar surface area in lung slices and the activity of pro- (NADPH and xanthine oxidases-NOX and XO) and anti- (superoxide dismutase, and glutathione peroxidase-SOD and GPx) oxidant enzymes in cytosolic and mitochondrial lung protein extracts. HA rats have a lower arterial oxygen saturation and reduced alveolar surface area compared to HA mice and SL rats. Enzymatic activities (NOX, XO, SOD, and GPx) in the cytosol were similar between HA and SL animals, but SOD and GPx activities in the mitochondria were 2-3 times higher in HA vs. SL rats, and only marginally higher in HA mice vs. SL mice. Furthermore, the maximum activity of cytochrome oxidase-c (COX) measured in mitochondrial lung extracts was also 2 times higher in HA rats compared with SL rats, while there was only a small increase in HA mice vs. SL mice. Interestingly, compared with SL controls, alterations in lung morphology are not observed for young rats at HA (15 days after birth), and enzymatic activities are only slightly altered. These results suggest that rats living at HA have a gradual reduction of their alveolar surface area beyond the postnatal period. We can speculate that the elevation of SOD, GPx, and COX activities in the lung mitochondria are not sufficient to compensate for oxidative stress, leading to damage of the lung tissue in rats.
Genetic ancestry of families of putative Inka descent
(Springer Science+Business Media, 2018) José R. Sandoval; Daniela R. Lacerda; Marilza S. Jota; Ronald Elward; Óscar Acosta; Donaldo Pinedo; Pierina Danós; Cinthia Cuellar; Susana Revollo; Fabrício R. Santos
Genetic ancestry of families of putative Inka descent.
(LA Referencia, 2018) José R. Sandoval; Lacerda, Daniela R; Marilza S. Jota; Ronald Elward; Óscar Acosta; Donaldo Pinedo; Pierina Danós; Cinthia Cuellar; Susana Revollo; Fabrício R. Santos
This study focuses on the descendants of the royal Inka family. The Inkas ruled Tawantinsuyu, the largest pre-Columbian empire in South America, which extended from southern Colombia to central Chile. The origin of the royal Inkas is currently unknown. While the mummies of the Inka rulers could have been informative, most were destroyed by Spaniards and the few remaining disappeared without a trace. Moreover, no genetic studies have been conducted on present-day descendants of the Inka rulers. In the present study, we analysed uniparental DNA markers in 18 individuals predominantly from the districts of San Sebastian and San Jerónimo in Cusco (Peru), who belong to 12 families of putative patrilineal descent of Inka rulers, according to documented registries. We used single-nucleotide polymorphisms and short tandem repeat (STR) markers of the Y chromosome (Y-STRs), as well as mitochondrial DNA D-loop sequences, to investigate the paternal and maternal descent of the 18 alleged Inka descendants. Two Q-M3* Y-STR clusters descending from different male founders were identified. The first cluster, named AWKI-1, was associated with five families (eight individuals). By contrast, the second cluster, named AWKI-2, was represented by a single individual; AWKI-2 was part of the Q-Z19483 sub-lineage that was likely associated with a recent male expansion in the Andes, which probably occurred during the Late Intermediate Period (1000-1450 AD), overlapping the Inka period. Concerning the maternal descent, different mtDNA lineages associated with each family were identified, suggesting a high maternal gene flow among Andean populations, probably due to changes in the last 1000 years.
Genetic portrait of the Amazonian communities of Peru and Bolivia: The legacy of the Takanan‐speaking people
(Wiley, 2023) José R. Sandoval; Susana Revollo; Cinthia Cuellar; Daniela R. Lacerda; Marilza S. Jota; Ricardo Fujita; Fabrício R. Santos
During the colonial period in South America, many autochthonous populations were affected by relocation by European missionary reductions and other factors that impacted and reconfigured their genetic makeup. Presently, the descendants of some "reduced" and other isolated groups are distributed in the Amazonian areas of Peru, Bolivia, and Brazil, and among them, speakers of Takanan and Panoan languages. Based on linguistics, these peoples should be closely related, but so far no DNA comparison studies have been conducted to corroborate a genetic relationship. To clarify these questions, we used a set of 15 short tandem repeats of the non-recombining part of the Y-chromosome (Y-STRs) and mitochondrial DNA (mtDNA) control region sequence data. Paternal line comparisons showed the Takanan-speaking peoples from Peru and Bolivia descended from recent common ancestors; one group was related to Arawakan, Jivaroan, and Cocama and the other to Panoan speakers, consistent with linguistics. Also, a genetic affinity for maternal lines was observed between some Takanan speakers and individuals who spoke different Amazonian languages. Our results supported a shared ancestry of Takanan, Panoan, Cocama, and Jivaroan-speaking communities who appeared to be related to each other and came likely from an early Arawak expansion in the western Amazonia of South America.
Hypercapnic ventilatory response is decreased in a mouse model of excessive erythrocytosis
(American Physiological Society, 2016) Sofien Laouafa; Elizabeth Elliot‐Portal; Susana Revollo; Edith M. Schneider Gasser; Vincent Joseph; Nicolas Voituron; Max Gassmann; Jorge Soliz
The impact of cerebral erythropoietin (Epo) in the regulation of the hypercapnic ventilatory response (HcVR) is controversial. While we reported that cerebral Epo does not affect the central chemosensitivity in C57Bl6 mice receiving an intracisternal injection of sEpoR (the endogenous antagonist of Epo), a recent study in transgenic mice with constitutive high levels of human Epo in brain and circulation (Tg6) and in brain only (Tg21), showed that Epo blunts the HcVR, maybe by interacting with central and peripheral chemoreceptors. High Epo serum levels in Tg6 mice lead to excessive erythrocytosis (hematocrit ~80-90%), the main symptom of chronic mountain sickness (CMS). These latter results support the hypothesis that reduced central chemosensitivity accounts for the hypoventilation observed in CMS patients. To solve this intriguing divergence, we reevaluate HcVR in Tg6 and Tg21 mouse lines, by assessing the metabolic rate [O consumption (V̇) and CO production (V̇)], a key factor modulating ventilation, the effect of which was not considered in the previous study. Our results showed that the decreased HcVR observed in Tg6 mice (~70% reduction; < 0.01) was due to a significant decrease in the metabolism (~40%; < 0.0001) rather than Epo's effect on CO chemosensitivity. Additional analysis in Tg21 mice did not reveal differences of HcVR or metabolism. We concluded that cerebral Epo does not modulate the central chemosensitivity system, and that a metabolic effect upon CO inhalation is responsible for decreased HcVR observed in Tg6 animals. As CMS patients also show decreased HcVR, our findings might help to better understand respiratory disorders at high altitude.
In Vitro Benznidazole and Nifurtimox Susceptibility Profile of Trypanosoma cruzi Strains Belonging to Discrete Typing Units TcI, TcII, and TcV
(Multidisciplinary Digital Publishing Institute, 2019) Susana Revollo; Bruno Oury; Andrea Vela; Michel Tibayrenc; Denis Séréno
We ascertain the in vitro Benznidazole (BZN) and Nifurtimox (NFX) susceptibility pattern of epimastigotes, trypomastigotes, and amastigotes of 21 T. cruzi strains, from patients, reservoir, and triatomine bugs of various geographic origins. Using this panel of isolates, we compute the Epidemiological cut off value (COwt). Then, the frequency of the susceptible phenotype (Wild type) towards benznidazole (BZN) and nifurtimox (NFX) within this set of strains belonging to three discrete typing units (DTUs), TcI, TcII, and TcV, was deduced. We observed that the susceptibility status of individual T. cruzi isolates toward BZN and NFX is related to the genetic background and underlying factors that are probably related to the individual life trait history of each strain. Analyzing drug susceptibility in this conceptual framework would offer the possibility to evidence a link between isolates expressing a low susceptibility level (not wild-type) as defined by the COwt value and none-curative treatment. It will also permit us to track drug-resistant parasites in the T. cruzi population.
Isoenzyme characterization of Leishmania braziliensis braziliensis isolates obtained from Bolivian and Peruvian patients
(Oxford University Press, 1992) Susana Revollo; L. Dimier-David; C. David; Philippe Lyèvre; Clara Camacho; Jean-Pierre Dedet
Thirty-four Leishmania isolates obtained from Bolivian and Peruvian patients infected with mucocutaneous leishmaniasis were characterized by isoenzyme electrophoresis using 10 enzymatic markers; all belonged to the subspecies L.b. braziliensis. Three isolates showed marked variation compared with the reference strain with respect to 5 or 6 enzymes. These variant isolates originated from patients with forms of the disease which were unresponsive to treatment.
Lower urinary tract dysfunction in chronic Chagas disease: clinical and urodynamic presentation
(Springer Science+Business Media, 2018) É. Bey; Maria Brigitte Paucara Condori; Olivier Gaget; Philippe Solano; Susana Revollo; C. Saussine; Simone Frédérique Brénière
New native South American Y chromosome lineages
(Springer Nature, 2016) Marilza S. Jota; Daniela R. Lacerda; José R. Sandoval; Pedro Paulo Vieira; Dominique Ohasi; José E Santos-Júnior; Óscar Acosta; Cinthia Cuellar; Susana Revollo; César Paz‐y‐Miño
Parasitological diagnosis of mucocutaneous leishmaniasis due to Leishmania b. braziliensis in Bolivia
(Brazilian Society of Tropical Medicine, 1991) L. Dimier-David; Christophe David; P Ravisse; R Bustillos; Susana Revollo; Philippe Lyèvre; M Muñoz; Fernando Regla Vargas; Jean-Pierre Dedet
Parasitological diagnosis, using stained smears, culture and pathological examination of biopsy, was studied in 146 patients infected with mucocutaneous leishmaniasis, in Bolivia and Peru. The most efficient parasite detecting technique appeared to be the smear examination in cutaneous lesions (33% positive) and the pathology in case of mucous lesions (28% positive). In both, cutaneous and mucous lesions, the parasites were found most frequently in old lesions.
POLYMERASE CHAIN REACTION DETECTION AND SEROLOGIC FOLLOW-UP AFTER TREATMENT WITH BENZNIDAZOLE IN BOLIVIAN CHILDREN INFECTED WITH A NATURAL MIXTURE OF TRYPANOSOMA CRUZI I AND II
(American Society of Tropical Medicine and Hygiene, 2006) María Flóres-Chávez; Marie-France Bosseno; Brigitte Bastrenta; JOSE-LOUIS ALCAZAR DALENZ; Mireille Hontebeyrie; Susana Revollo; Simone Frédérique Brénière
Thirty-five Bolivian children (5-10 years of age) seropositive for infection with T. cruzi underwent specific chemotherapy with benznidazole. Before treatment, 57.1% had a positive parasitologic diagnosis. Some patients presented an early conversion by polymerase chain reaction of blood samples, while others were still positive four and seven months after the end of the treatment, which indicated an absence of parasite clearance. Strain typing showed that most patients were infected by a mixture of clones I and II of T. cruzi. Serologic conversion in conventional tests and antibodies to shed acute-phase antigen were observed in two and four patients, respectively. For the other patients, the average rate of antibody decay was half the initial rate. The parasitologic and serologic data indicated that chemotherapy acts throughout the course of infection in a long-lasting process in which the decrease of specific antibody production is related to the reduction of the live parasite load.
The Genetic History of Indigenous Populations of the Peruvian and Bolivian Altiplano: The Legacy of the Uros
(Public Library of Science, 2013) José R. Sandoval; Daniela R. Lacerda; Marilza S. Jota; Alberto Salazar‐Granara; Pedro Paulo Vieira; Óscar Acosta; Cinthia Cuellar; Susana Revollo; Ricardo Fujita; Fabrício R. Santos
The Altiplano region of the South American Andes is marked by an inhospitable climate to which the autochthonous human populations adapted and then developed great ancient civilizations, such as the Tiwanaku culture and the Inca Empire. Since pre-Columbian times, different rulers established themselves around the Titicaca and Poopo Lakes. By the time of the arrival of Spaniards, Aymara and Quechua languages were predominant on the Altiplano under the rule of the Incas, although the occurrence of other spoken languages, such as Puquina and Uruquilla, suggests the existence of different ethnic groups in this region. In this study, we focused on the pre-Columbian history of the autochthonous Altiplano populations, particularly the Uros ethnic group, which claims to directly descend from the first settlers of the Andes, and some linguists suggest they might otherwise be related to Arawak speaking groups from the Amazon. Using phylogeographic, population structure and spatial genetic analyses of Y-chromosome and mtDNA data, we inferred the genetic relationships among Uros populations (Los Uros from Peru, Uru-Chipaya and Uru-Poopo from Bolivia), and compared their haplotype profiles with eight Aymara, nine Quechua and two Arawak (Machiguenga and Yanesha) speaking populations from Peru and Bolivia. Our results indicated that Uros populations stand out among the Altiplano populations, while appearing more closely related to the Aymara and Quechua from Lake Titicaca and surrounding regions than to the Amazon Arawaks. Moreover, the Uros populations from Peru and Bolivia are genetically differentiated from each other, indicating a high heterogeneity in this ethnic group. Finally, our results support the distinctive ancestry for the Uros populations of Peru and Bolivia, which are likely derived from ancient Andean lineages that were partially replaced during more recent farming expansion events and the establishment of complex civilizations in the Andes.
Trypanosoma cruzi: expression of antigenic component 5 among 35 laboratory clones obtained from 18 different isozymic variants
(University of São Paulo, 1987) Simone Frédérique Brénière; Susana Revollo; T Caillard; Eric Velatte; Dominique Legrand; D. Afchain; P. Desjeux
Two monoclonal antibodies anti-component 5 of Trypanosoma cruzi (I-35/115 and II-190/30) were tested in IFA and ELISA respectively against 35 T. cruzi laboratory clones. Among the 35 clones tested, 18 different isozyme patterns were detected. All clones were recognized by both monoclonal antibodies except one clone which did not react with II-190/30. These results support the universal expression of specific component 5 within the taxon T. cruzi.
UN NUEVO ENFOQUE PARA IDENTIFICAR SARS COV-2 BASADO EN MULTIPLEX RT-PCR Y ELECTROFORESIS CAPILAR
(2022) Susana Revollo; Yashira Cerruto; Marcos V. Conde; Miguel Ángel Cornejo; Victor Manuel Miranda
Resumen: La detección rápida de SARS-CoV-2 en pacientes es una herramienta crítica para monitorear la propagación de la enfermedad, guiar las decisiones terapéuticas y diseñar protocolos de distanciamiento social.La prueba de RT-PCR en tiempo real para la identificación de SARS-CoV-2, utilizada como prueba "Gold Estándar" desde el inicio de la pandemia COVID 19, ha mostrado en algunos estudios, resultados falsos negativos y falsos positivos, por lo que se ha visto indispensable contar con una prueba que discrimine claramente estos resultados.La electroforesis capilar (EC) es una herramienta de separación de biomoléculas, que puede realizarse en corto tiempo, se requiere de pequeñas cantidades de muestra y tiene una alta reproducibilidad.Estas características hacen que la EC sea un método eficiente y económico con capacidad de separar cientos de componentes de forma simultánea, razones suficientes para ser una herramienta de elección para la identificación de SARS-CoV-2.En el estudio se describe un enfoque técnico para la identificación de SARS-CoV-2 mediante la amplificación de secuencias del genoma viral de los genes N, S, y ORF1ab por Multiplex RT-PCR, seguido de una electroforesis capilar (Multiplex RT-PCR-EC).La validación de esta prueba ha demostrado ser un método selectivo en un 97%, específico en un 91%, sensible en un 100%, con una eficiencia del 98% y una precisión del 100%.Esta prueba ha permitido, además, identificar resultados falsos positivos de COVID 19 diagnosticados con RT-PCR en tiempo real en un 16% de los pacientes incluidos en el estudio.La prueba Multiplex RT-PC-EC puede ser una alternativa para facilitar el análisis cuando, por un lado, la demanda de pruebas de COVID-19 excediera la capacidad de la PCR y por otro, cuando se genere una incertidumbre en el valor de CT obtenido por RT-PCR en tiempo real.