Search

Geochronological databases are powerful tools for characterizing the crustal evolution and the age spectra of a region and allow comparison with other areas at a regional scale. In this contribution, we present the Colombian Geochronological Database (CGD), which contains a curated compilation of ca. 67,406 individual published U-Th-Pb, K-Ar, Ar-Ar, Rb-Sr, Sm-Nd, Lu-Hf, Fission-track, U-Th-He, and Re-Os mineral and whole rock ages that are reported in the published literature. Each date includes geographic coordinates, geological setting, petrologic and chemical information extracted from the respective publications. The structure of the database provides a powerful interface for constructing queries and allows searching and extracting information on geographic domains, provinces, stratigraphic units, isotopic systems, date interpretations, references, etc. This information establishes a framework for regional and global geological interpretations with geochronological, stratigraphic, structural and palaeogeographic implications. With the present effort we present to the geoscience community a clear insight, from a regional perspective, to the geology and tectonics of Colombia since Precambrian times. The comparison of all (detrital and magmatic) single zircon U-Pb dates from the Colombian (Gondwana sourced) geochronological database with the Global and North American (Laurentia sourced) databases provides a temporal constraint on the evolution of the South American continent. U-Pb zircon ages in Colombia define 13 peak clusters centred at 1767, 1530, 1325, 1178, 1007, 605,540, 468, 271, 237, 182, 76 and 10 Ma but of those, only few have a good correlation in all three databases: 1007 (Grenvillian/Orinoquian/Putumayo Orogeny), 605 (Braziliano/Pan-African Orogeny), 468 (Famatinian/Taconic Orogeny), and 182 Ma (Break-up of Pangea) zircon peaks. This correlation suggests that some tectonic events in Colombia are global and might represent crustal production and preservation while the other peaks might just represent local arc magmatic events. [ABSTRACT FROM AUTHOR]

Background: Integrating early childhood parenting programmes into existing government services is a key strategy for reducing the loss of children's developmental potential in low‐ and middle‐income countries. There is limited evidence of participants' perceptions of these programmes, especially when implemented at scale. We integrated an intervention into an existing government programme targeting pregnant women and mothers of children up to 2 years of age and their families in rural Colombia. Methods: As part of a cluster randomized trial, 171 government workers (facilitators) implemented the intervention. The intervention included four components: (1) structured curricula, (2) play materials, (3) nutrition and (4) training and supervision. In this qualitative evaluation of the programme, we conducted semi‐structured interviews with beneficiary mothers (n = 62), facilitators (n = 40) and supervisors (n = 8). Topic guides were developed to collect information on participants' perspectives of the acceptability, feasibility and effectiveness of the intervention and the enablers and barriers to implementation. All interviews were audiotaped and transcribed, and data were analysed using the framework approach. Results: Participants' responses indicated that the intervention was acceptable, feasible and effective. Key enablers to implementation were (1) the use of evidence‐based behaviour change techniques leading to interactive, fun and participatory sessions; (2) structured curricula with easy to use, simple activities and materials; (3) the focus on positive, supportive relationships; and (4) the perceived benefits of the programme to the beneficiary mothers, children and families, facilitators and programme supervisors. The main barriers were (1) facilitators took time to become comfortable and competent in using the new participatory methodology and (2) the logistics related to making and distributing the play materials. Conclusion: Providing structured curricula and play materials with training and ongoing supervision to enhance an existing programme targeting mothers, families and children was reported as acceptable, feasible and effective by beneficiary mothers and programme staff. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: Leishmania parasites reside within macrophages and the direct target of antileishmanial drugs is therefore intracellular. We aimed to characterize the intracellular PBMC miltefosine kinetics by developing a population pharmacokinetic (PK) model simultaneously describing plasma and intracellular PBMC pharmacokinetics. Furthermore, we explored exposure-response relationships and simulated alternative dosing regimens.Patients and methods: A population PK model was developed with NONMEM, based on 339 plasma and 194 PBMC miltefosine concentrations from Colombian cutaneous leishmaniasis patients [29 children (2-12 years old) and 22 adults] receiving 1.8-2.5 mg/kg/day miltefosine for 28 days.Results: A three-compartment model with miltefosine distribution into an intracellular PBMC effect compartment best fitted the data. Intracellular PBMC distribution was described with an intracellular-to-plasma concentration ratio of 2.17 [relative standard error (RSE) 4.9%] and intracellular distribution rate constant of 1.23 day-1 (RSE 14%). In exploring exposure-response relationships, both plasma and intracellular model-based exposure estimates significantly influenced probability of cure. A proposed PK target for the area under the plasma concentration-time curve (day 0-28) of >535 mg·day/L corresponded to >95% probability of cure. In linear dosing simulations, 18.3% of children compared with 2.8% of adults failed to reach 535 mg·day/L. In children, this decreased to 1.8% after allometric dosing simulation.Conclusions: The developed population PK model described the rate and extent of miltefosine distribution from plasma into PBMCs. Miltefosine exposure was significantly related to probability of cure in this cutaneous leishmaniasis patient population. We propose an exploratory PK target, which should be validated in a larger cohort study. [ABSTRACT FROM AUTHOR]

Copyright of Colombia Medica is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel pan- Leishmania loop-mediated isothermal amplification (LAMP) assay for the diagnosis of cutaneous and visceral leishmaniasis (CL and VL) that can be used in near-patient settings was developed. Primers were designed based on the 18S ribosomal DNA (rDNA) and the conserved region of minicircle kinetoplast DNA (kDNA), selected on the basis of high copy number. LAMP assays were evaluated for CL diagnosis in a prospective cohort trial of 105 patients in southwest Colombia. Lesion swab samples from CL suspects were collected and were tested using the LAMP assay, and the results were compared to those of a composite reference of microscopy and/or culture in order to calculate diagnostic accuracy. LAMP assays were tested on samples (including whole blood, peripheral blood mononuclear cells, and buffy coat) from 50 suspected VL patients from Ethiopia. Diagnostic accuracy was calculated against a reference standard of microscopy of splenic or bone marrow aspirates. To calculate analytical specificity, 100 clinical samples and isolates from fever-causing pathogens, including malaria parasites, arboviruses, and bacteria, were tested. We found that the LAMP assay had a sensitivity of 95% (95% confidence interval [CI], 87.2% to 98.5%) and a specificity of 86% (95% CI, 67.3% to 95.9%) for the diagnosis of CL. With VL suspects, the sensitivity of the LAMP assay was 92% (95% CI, 74.9% to 99.1%) and its specificity was 100% (95% CI, 85.8% to 100%) in whole blood. For CL, the LAMP assay is a sensitive tool for diagnosis and requires less equipment, time, and expertise than alternative CL diagnostics. For VL, the LAMP assay using a minimally invasive sample is more sensitive than the gold standard. Analytical specificity was 100%., (Copyright © 2018 Adams et al.)

Introduction: Abnormal levels of the enzyme methylenetetrahydrofolate reductase (MTHFR) are associated with an increased risk of both cardiovascular and cerebrovascular disease and higher concentrations of homocysteine. Abnormal levels are also related to birth defects, pregnancy complications, cancer and toxicity to methotrexate (MTX). Polymorphisms of MTHFR affect the activity of the enzyme. Genetic associations have been related to treatment efficacy., Objective: To establish the frequency of the C> T polymorphism at nucleotide 677 of the MTHFR gene in a group of Colombian individuals., Methods: Data from pharmacogenetic microarrays that include MTX sensibility-associated polymorphisms were retrospectively collected (Pathway Genomics(®)). The frequency of the C> T MTHFR rs1801133 marker polymorphism was analyzed., Results: Microarray data from 68 men and 84 women were analyzed. Comparisons of genotype C/C vs. C/T and T/T were statistically significantly different (p= 0.00, p= 0.026, respectively), as were C/T and T / T (p= 0.0001)., Conclusions: Results for the C/C and C/T genotypes in a Colombian population are similar to other previously studied groups of healthy subjects. Subjects from our population might be at risk of developing diseases associated with MTHFR polymorphisms and might present toxicity and adverse effects if treated with MTX, which suggests the need to evaluate therapeutic alternatives based on individual pharmacogenetic studies.

Febrile seizures and epilepsy are believed to be linked and some forms of epilepsy are associated with a history of febrile seizures (FS). Linkage analysis to seven known loci for FS and/or genetic epilepsy with febrile seizures plus (GEFS plus) was performed in a small Colombian family. Short tandem repeat (STR) markers were genotyped and two-point linkage analysis and haplotype reconstruction were conducted. A maximum LOD score of 0.75 at marker D8S533 for FEB1 at a recombination fraction (θ) of 0 and a segregating haplotype were identified. FEB1 was the first locus to be associated with FS and this is the second report to describe this association. Two genes in this region, CRH and DEPDC2, are good putative candidate genes that may play a role in FS and/or GEFS plus.

Peridomestic transmission of American cutaneous leishmaniasis is increasingly reported and dogs may be a reservoir of Leishmania (Viannia) in this setting. We investigated the prevalence of infection in dogs in Chaparral County, Colombia, the focus of an epidemic of human cutaneous leishmaniasis caused by Leishmania (Viannia) guyanensis. Two (0.72%) of 279 dogs had lesions typical of cutaneous leishmaniasis that were biopsy positive by kinetoplast DNA polymerase chain reaction-Southern blotting. Seroprevalence was 2.2% (6 of 279) by enzyme-linked immunosorbent assay. Buffy coat and ear skin biopsy specimens were positive by polymerase chain reaction-Southern blotting in 7.3% (10 of 137) and 11.4% (12 of 105) of dogs, respectively. Overall 20% of dogs (21 of 105) showed positive results for one or more tests. Amplification and sequencing of the Leishmania 7SL RNA gene identified L. guyanensis in one dog and L. braziliensis in two dogs. No association was identified between the risk factors evaluated and canine infection. Dogs may contribute to transmission but their role in this focus appears to be limited.