Browsing by Tema "Biology"

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153 DETECTING PRE-OVULATORY LUTEINIZING HORMONE PEAKS IN ORDER TO OPTIMIZE THE RATIO OF VIABLE EMBRYOS USING PREDI'BOV®, A NEW ON-FARM OVULATION TEST
(CSIRO Publishing, 2012) Laurence Dupuy; Charlotte Joly; Jérémy Decourtye; Pascal Salvetti; Ervin E. Kara; Alexandre Morel; F. Charreaux; S. Lacaze; Joel Schwartz; Claire Ponsart
The LH peak in cattle is the most precise event for predicting ovulation beginning 24 h later, and thus, AI time. Previous studies demonstrated that embryo production was improved when AI was conducted 12 h before ovulation; that is, 12 h after LH peak. This study aimed to evaluate the benefit of LH peak monitoring with Predi'Bov® (ReproPharm®, Nouzilly, France) following superstimulation in order to optimize numbers of viable embryos (VE). Predi'Bov® is a rapid (40 min) and easy to use on-farm test allowing LH peak detection from a few drops of blood. The test was also used to estimate the variability in the time of the LH peak and onset of oestrus. This study was conducted by the embryo transfer teams of 3 French cooperatives, in collaboration with UNCEIA. Forty heifers in stations (Creavia, Midatest) and 23 cows on farms (GEN'Iatest) were superstimulated by 8 injections IM of Stimufol® or Pluset® (FSH1 to FSH8) over 4 days in 2011–2012. Donor station heifers were treated twice in a Latin square design with a reference protocol where AI was conducted 12 and 24 h after onset of oestrus, and in an experimental protocol where AI was conducted 12 and 24 h after a positive Predi'Bov® test. Semen of different sires was used for both protocols. The Predi'Bov® test was carried out on 3 blood samples (BS1,2,3) collected every 6 h beginning at FSH7 in stations and FSH8 on farms to detect the earliest LH peaks. To determine late LH peaks, Predi'Bov® test was carried out on BS4 collected 24 h after FSH8. Univariate statistical analysis was performed to look at the relationship between qualitative (chi-square) and quantitative (t-test) variables. The difference was considered significant when P &lt; 0.05. The Predi'Bov® test showed that 37.5% (15/40) of LH peaks occurred during the last day of FSH treatment (BS1 or BS2) in stations and 26.1% (6/23) at BS1 on farms. At Creavia station (n = 24), the LH peak was detected anytime from 24 h before to 9 h after the onset of oestrus. In stations, the VE percentage did not differ whether AI was done following oestrus or LH peak detection (63.1% and 61.8% in reference and experimental protocols, respectively). In stations, the VE percentage from 9 females with an LH peak detected at FSH7 (BS1; 41%) in the reference protocol did not differ from the experimental protocol (50%). On farms, the VE percentage was numerically higher but not significant in the experimental protocol (65.4%, n = 16) compared to the reference protocol (47.2%, n = 7). Further investigations are needed, taking into account the effect of collection rank, sire, and female effects, to confirm the trends shown by these results. In conclusion, Predi'Bov® can be used as easily on farms as in stations. Its use allows the detection of animals that have early or late LH peaks, which in turn provides the opportunity of carrying out AI at the optimal time for such females.
15N in tree rings as a bio-indicator of changing nitrogen cycling in tropical forests: an evaluation at three sites using two sampling methods
(Frontiers Media, 2015) Peter van der Sleen; Mart Vlam; Peter Groenendijk; Niels P. R. Anten; Frans Bongers; Sarayudh Bunyavejchewin; Peter Hietz; Thijs L. Pons; Pieter A. Zuidema
Anthropogenic nitrogen deposition is currently causing a more than twofold increase of reactive nitrogen input over large areas in the tropics. Elevated (15)N abundance (δ(15)N) in the growth rings of some tropical trees has been hypothesized to reflect an increased leaching of (15)N-depleted nitrate from the soil, following anthropogenic nitrogen deposition over the last decades. To find further evidence for altered nitrogen cycling in tropical forests, we measured long-term δ(15)N values in trees from Bolivia, Cameroon, and Thailand. We used two different sampling methods. In the first, wood samples were taken in a conventional way: from the pith to the bark across the stem of 28 large trees (the "radial" method). In the second, δ(15)N values were compared across a fixed diameter (the "fixed-diameter" method). We sampled 400 trees that differed widely in size, but measured δ(15)N in the stem around the same diameter (20 cm dbh) in all trees. As a result, the growth rings formed around this diameter differed in age and allowed a comparison of δ(15)N values over time with an explicit control for potential size-effects on δ(15)N values. We found a significant increase of tree-ring δ(15)N across the stem radius of large trees from Bolivia and Cameroon, but no change in tree-ring δ(15)N values over time was found in any of the study sites when controlling for tree size. This suggests that radial trends of δ(15)N values within trees reflect tree ontogeny (size development). However, for the trees from Cameroon and Thailand, a low statistical power in the fixed-diameter method prevents to conclude this with high certainty. For the trees from Bolivia, statistical power in the fixed-diameter method was high, showing that the temporal trend in tree-ring δ(15)N values in the radial method is primarily caused by tree ontogeny and unlikely by a change in nitrogen cycling. We therefore stress to account for tree size before tree-ring δ(15)N values can be properly interpreted.
16S rRNA Gene Diversity in Ancient Gray and Pink Salt from San Simón Salt Mines in Tarija, Bolivia
(American Society for Microbiology, 2020) Wolf T. Pecher; Fabiana Lilian Martínez; Priya DasSarma; Daniel Guzmán; Shiladitya DasSarma
DNA from 250 million-year-old pink and gray salts from mines in Tarija, Bolivia, subjected to 16S rRNA gene amplicon sequencing and analysis provided evidence for similar but distinct prokaryotic communities. The results constitute a snapshot of archaeal and bacterial microorganisms in these remote and ancient salt deposits.
16S rRNA Gene Diversity in the Salt Crust of Salar de Uyuni, Bolivia, the World’s Largest Salt Flat
(American Society for Microbiology, 2020) Wolf T. Pecher; Fabiana Lilian Martínez; Priya DasSarma; Daniel Guzmán; Shiladitya DasSarma
Salar de Uyuni is a vast, high-altitude salt flat in Bolivia with extreme physico-geochemical properties approaching multiple limits of life. Evidence for diverse halophilic bacteria and archaea was found in its surface and near-surface salt crust using 16S amplicon analysis, providing a snapshot of prokaryotic life.
17. Pig performance from post-weaning to the slaughterhouse before and after implementing oral vaccination against E. coli F4/F18
(Elsevier BV, 2024) Jean-Jacques Sevin; L. Faisant; S. Vigneron; B. Fily; V. Burlot
2. 2018 LAM COL CAUCA_CCAFS_Arbol_de_Preguntas_Cuestionario.pdf
(Harvard University, 2019) Osana Bonilla‐Findji; Anton Eitzinger; Nadine Andrieu; Andy Jarvis; Deissy Martínez- Barón; Luis Alfonso Ortega; Jimmy Mañunga
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2. 2019_LAM_COL-CAU_Arbol_Cuestionario.pdf
(Harvard University, 2020) Osana Bonilla‐Findji; Anton Eitzinger; Andy Jarvis; Deissy Martínez- Barón; Jesus David Martínez-Salgado; Luis Alfonso Ortega; Jimmy Mañunga
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21-Hydroxylase gene mutant allele CYP21A2∗15 strongly linked to the resistant HLA haplotype B∗14:02-DRB1∗01:02 in chronic Chagas disease
(Elsevier BV, 2013) Florencia del Puerto; Mihoko Kikuchi; Juan Eiki Nishizawa; Yelin Roca; Cinthia Avila; Alberto Gianella; Javier Lora; Freddy Udalrico Gutierrez Velarde; Kenji Hirayama
3. 2019_LAM_COL-CAU_Glosario_practicas_ASAC.pdf
(Harvard University, 2020) Osana Bonilla‐Findji; Anton Eitzinger; Andy Jarvis; Deissy Martínez- Barón; Jesus David Martínez-Salgado; Luis Alfonso Ortega; Jimmy Mañunga
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7. 2019_LAM_COL-CAU_CIAT Minimum Risk Rewiew IRB Approval Letter.pdf
(Harvard University, 2020) Osana Bonilla‐Findji; Anton Eitzinger; Andy Jarvis; Deissy Martínez- Barón; Jesus David Martínez-Salgado; Luis Alfonso Ortega; Jimmy Mañunga
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A Trypanosoma cruzi trans-sialidase peptide demonstrates high serological prevalence among infected populations across endemic regions of Latin America
(2026) Hannah Kortbawi; Ryan Marczak; Jayant Rajan; Nash Bulaong; John E. Pak; Wesley Wu; Grace Wang; Anthea Mitchell; Aditi R. Saxena; Aditi Maheswari
Infection by Trypanosoma cruzi, the agent of Chagas disease, can irreparably damage the cardiac and gastrointestinal systems during decades of parasite persistence and related inflammation in these tissues. Diagnosis of chronic disease requires confirmation by multiple serological assays due to the imperfect performance of existing clinical tests. Current serology tests utilize antigens discovered over three decades ago with small specimen sets predominantly from South America, and lower test performance has been observed in patients who acquired T. cruzi infection in Central America and Mexico. Here, we attempt to address this gap by evaluating antibody responses against the entire T. cruzi proteome with phage display immunoprecipitation sequencing comprised of 228,127 47-amino acid peptides. We utilized diverse specimen sets from Mexico, Central America and South America, as well as different stages of cardiac disease severity, from 185 cases and 143 controls. We identified over 1,300 antigenic T. cruzi peptides derived from 961 proteins between specimen sets. A total of 67 peptides were reactive in 70% of samples across all regions, and 3 peptide epitopes were enriched in ≥90% of seropositive samples. Of these three, only one antigen, belonging to the trans-sialidase family, has not previously been described as a diagnostic target. Orthogonal validation of this peptide demonstrated increased antibody reactivity for infections originating from Central America. Overall, this study provides proteome-wide identification of seroreactive T. cruzi peptides across a large cohort spanning multiple endemic areas and identified a novel trans-sialidase peptide antigen (TS-2.23) with significant potential for translation into diagnostic serological assays.
A Trypanosoma cruzi Antigen and Epitope Atlas: deep characterization of antibody specificities in Chagas Disease patients across the Americas
(2022) Alejandro D. Ricci; Leonel Bracco; Janine M. Ramsey; Melissa S. Nolan; Mary K. Lynn; Jaime Altcheh; Griselda Ballering; Faustino Torrico; Norival Kesper; Juan Carlos Villar
ABSTRACT During an infection, the immune system produces pathogen-specific antibodies. With time, these antibody repertoires become specific to the history of infections and represent a rich source of diagnostic markers. However, the specificities of these antibodies are mostly unknown. Here, using high-density peptide arrays we examined the specificities of human antibody repertoires of Chagas disease patients. Chagas disease is a neglected disease caused by Trypanosoma cruzi, a protozoan parasite that evades immune mediated elimination and mounts long-lasting chronic infections. We describe here the first proteome-wide search for antigens and epitopes and their seroprevalence at the individual level and across human populations. In a first discovery screening of 2.84 million short peptides spanning two T. cruzi proteomes we found 3,868 distinct antigenic protein regions. Further analysis of repertoires from 71 individuals provided information on their seroprevalence and showed a large fraction of private epitopes of low seroprevalence (<20%), and novel high seroprevalence antigens. Using single-residue mutagenesis we found the core epitopes required for antibody binding for 232 of these epitopes. These datasets enable the study of the Chagas antibody repertoire at an unprecedented depth and granularity, while also providing a rich source of novel serological biomarkers. IMPACT STATEMENT This work reveals the diversity and extent of antibody specificities in Chagas Disease and provides a wealth of well-defined antigenic markers for diagnosis and development of serological applications for this neglected infectious disease.
A Trypanosoma cruzi Trans-Sialidase Peptide Demonstrates High Serological Prevalence Among Infected Populations Across Endemic Regions of Latin America
(2025) Hannah Kortbawi; Ryan Marczak; Jayant V. Rajan; Nash L Bulaong; John E. Pak; Wesley Wu; Grace Wang; Anthea Mitchell; Aditi Saxena; Anshu Maheswari
Infection by Trypanosoma cruzi, the agent of Chagas disease, can irreparably damage the cardiac and gastrointestinal systems during decades of parasite persistence and related inflammation in these tissues. Diagnosis of chronic disease requires confirmation by multiple serological assays due to the imperfect performance of existing clinical tests. Current serology tests utilize antigens discovered over three decades ago with small specimen sets predominantly from South America, and lower test performance has been observed in patients who acquired T. cruzi infection in Central America and Mexico. Here, we attempt to address this gap by evaluating antibody responses against the entire T. cruzi proteome with phage display immunoprecipitation sequencing comprised of 228,127 47-amino acid peptides. We utilized diverse specimen sets from Mexico, Central America and South America, as well as different stages of cardiac disease severity, from 185 cases and 143 controls. We identified over 1,300 antigenic T. cruzi peptides derived from 961 proteins between specimen sets. A total of 67 peptides were reactive in 70% of samples across all regions, and 3 peptide epitopes were enriched in ≥90% of seropositive samples. Of these three, only one antigen, belonging to the trans-sialidase family, has not previously been described as a diagnostic target. Orthogonal validation of this peptide demonstrated increased antibody reactivity for infections originating from Central America. Overall, this study provides proteome-wide identification of seroreactive T. cruzi peptides across a large cohort spanning multiple endemic areas and identified a novel trans-sialidase peptide antigen (TS-2.23) with significant potential for translation into diagnostic serological assays.
A camera trapping survey of mammals in the mixed landscape of&nbsp;Bolivia&rsquo;s Chiquitano region with a special focus on the Jaguar
(Pensoft Publishers, 2020) Martin Jansen; Marc Engler; Luka Moritz Blumer; Damián I. Rumiz; José Luis Aramayo; Oliver Krone
At a site in the Bolivian Chiquitano region composed by a mosaic of pastureland and primary Chiquitano Dry Forest&nbsp;(CDF) we conducted a camera-trapping study to (1) survey the mammals, and (2) compare individual Jaguar numbers&nbsp;with other Chiquitano sites. Therefore, we installed 13 camera stations (450 ha polygon) over a period of six months.&nbsp;On 1,762 camera-days and in 1,654 independent capture events, we recorded 24 mammalian species that represent the&nbsp;native fauna of large and medium-sized mammals including apex-predators (Puma, Jaguar), meso-carnivores (Ocelot,&nbsp;Jaguarundi, Margay), and large herbivores (Tapir, Collared and White lipped Peccary). We identified six adult Jaguars&nbsp;and found indications of successful reproductive activity. Captures of Jaguars were higher in CDF than in altered habitats.&nbsp;In summary, we believe that (1) the mammal species richness, (2) the high capture numbers of indicator species,&nbsp;and (3) the high capture numbers of Jaguar indicate that our study area has a good conservation status. Future efforts&nbsp;should be undertaken to keep this, and monitoring programs in this region are necessary to further evaluate the potential&nbsp;importance of the Chiquitano region as a possible key region for mammals, especially Jaguars, in South America.
A case of playful interaction between Bolivian river dolphins with a Beni anaconda
(Wiley, 2022) Omar Machado Entiauspe-Neto; Steffen Reichle; A. Ríos
The authors declare no conflict of interest. Data (Entiauspe Neto et al., 2022) are available in Figshare at: https://doi.org/10.6084/m9.figshare.19236462.v1.
A catfish of the genus Trichomycterus from a thermal stream in southern South America (Teleostei, Siluriformes, Trichomycteridae), with comments on relationships within the genus
(Wiley, 2007) Leticia A. Fernández; Guido Miranda
The first record of two trichomycterid species from the thermal waters of a small stream in Miraflores, north of Potosí, Bolivia is given. The reported species are Trichomycterus therma n. sp. and Trichomycterus tiraquae . The new species differ from all congeners in the possession of thickened transverse skin on the ventral surface of the head. They are further distinguished from all congeners by the following combination of characteristics: presence of spatulate incisiform premaxillary teeth; presence of large and rounded papilla‐like structures on trunk of body; continuous segment of the laterosensory canal within the frontal with the presence of a segment between pores 2 and 6; long laterosensory canal with four to six pores; maxilla with a short anterior process that is smaller than the main axis of the bone, and has an anterior orientation; mesethmoid shaft narrower than the width of the lateral cornua; prepelvic length 58·7–61·0% of standard length ( L S ); head width 19·1–22·8% of L S ; submaxillary barbel length 23·9–37·5% of head length ( L H ). Two derived characters, namely the presence of spatulate incisiform premaxillary teeth and large and rounded papilla‐like structures, define a monophyletic group within Trichomycterus , comprising T. therma , T. corduvensis and T. tiraquae .
A Chloroplast COR413 Protein From Physcomitrella patens Is Required for Growth Regulation Under High Light and ABA Responses
(Frontiers Media, 2020) Cecilia Ruibal; Alexandra Castro; Andrea L. Fleitas; Jorge A. N. Quezada; Gastón Quero; Sabina Vidal
COR413 genes belong to a poorly characterized group of plant-specific cold-regulated genes initially identified as part of the transcriptional activation machinery of plants during cold acclimation. They encode multispanning transmembrane proteins predicted to target the plasma membrane or the chloroplast inner membrane. Despite being ubiquitous throughout the plant kingdom, little is known about their biological function. In this study, we used reverse genetics to investigate the relevance of a predicted chloroplast localized COR413 protein (PpCOR413im) from the moss Physcomitrella patens in developmental and abiotic stress responses. Expression of PpCOR413im was strongly induced by abscisic acid (ABA) and by various environmental stimuli, including low temperature, hyperosmosis, salinity and high light. In vivo subcellular localization of PpCOR413im-GFP fusion protein revealed that this protein is localized in chloroplasts, confirming the in silico predictions. Loss-of-function mutants of PpCOR413im exhibited growth and developmental alterations such as growth retardation, reduced caulonema formation and hypersensitivity to ABA. Mutants also displayed altered photochemistry under various abiotic stresses, including dehydration and low temperature, and exhibited a dramatic growth inhibition upon exposure to high light. Disruption of PpCOR413im also caused altered chloroplast ultrastructure, increased ROS accumulation, and enhanced starch and sucrose levels under high light or after ABA treatment. In addition, loss of PpCOR413im affected both nuclear and chloroplast gene expression in response to ABA and high light, suggesting a role for this gene downstream of ABA in the regulation of growth and environmental stress responses. Developmental alterations exhibited by PpCOR413im knockout mutants had remarkable similarities to those exhibited by hxk1, a mutant lacking a major chloroplastic hexokinase, an enzyme involved in energy homeostasis. Based on these findings, we propose that PpCOR413im is involved in coordinating energy metabolism with ABA-mediated growth and developmental responses.
A COLORFUL NEW SPECIES OF NEOOREOPHILUS (ORCHIDACEAE: PLEUROTHALLIDINAE) FROM THE EASTERN ANDES OF COLOMBIA AND ECUADOR
(Universidad Autónoma del Estado de México, 2015) Sebastián Vieira-Uribe; Lou Jost
"A new species of Neooreophilus from the eastern Andes of Colombia and Ecuador is described and illustrated. Neooreophilus chaoae is related to a group of species that includes N. cordilabius, N. chelosepalus and N. werneri characterized by having an obovate, pubescent dorsal sepal and spread or reflexed, non-pubescent lateral sepals ending with an apiculum. The new species can be distinguished by its narrowly triangular lateral sepals and its lip with lateral lobes not extending beyond the column. Notes about its natural habitat and conservation status are also given."
A comparative evaluation of microalgae for the degradation of piggery wastewater under photosynthetic oxygenation
(Elsevier BV, 2010) Ignacio de Godos; Virginia A. Vargas; Saúl Blanco; María Cruz García-González; Roberto Soto; Pedro A. García‐Encina; Eloy Bécares; Raúl Muñoz
A Comparison of the Phenotype of Dendritic Cells Derived from Discrete Peyer's Patch Macrophages of Non-Infected and Toxoplasma Gondii Infected Mice
(Japanese Society of Veterinary Science, 2003) Levi Makala; Julio C. S. Reyes; Yoshifumi Nishikawa; Yoshinori Tsushima; Xuenan Xuan; Xiaohong Huang; Hideyuki Nagasawa
A comparison of the expression of surface membrane antigens between dendritic cells (DC) derived from Peyer's patch macrophages (DPP-DC) of non-infected and Toxoplasma gondii (T. gondii) infected mice was performed. C57BL/6J mice aged 6-8 weeks of both sexes were infected orally with a 0.5 ml suspension containing 2 x 10(4) bradyzoites of the Beverley strain of T. gondii, sacrificed on day 8 and DC generated using discrete Peyer's patch macrophages (DPP-Mø) as progenitor cells. When a comparison of the expression of surface membrane antigens between the antigen presenting cells (APC) obtained from discrete Peyer's patches of non-infected and T. gondii infected mice was carried out, no significant differences were observed in the macrophage progenitor and DC populations expression of F4/80, DEC-205, CD11c, CD80 (B7-1) and CD34. However, a significant decrease in MHC class II antigen levels and a down regulation of the co-stimulatory molecule CD86 (B7-2) were noted. B7-1 appeared to be the dominant co-stimulatory ligand, whereas B7-2, which was down regulated during T. gondii infection, had a weak expression. Taken together, these results may help clarify the role of DC in the complex network regulating surface membrane antigens, as well as, their capacity for antigen uptake, processing and presentation during toxoplasmosis.