Validation of a Standardized Procedure for Measuring Implicit Attitudes to Suicide / Validación de un procedimiento estandarizado de medición de actitudes implícitas frente al suicidio

Resumen El objetivo del estudio fue validar un procedimiento estandarizado de medición de actitudes implícitas frente al suicidio en estudiantes universitarios. Como criterios de validación concurrente para el Procedimiento de Evaluación Relacional Implícita (IRAP, abreviatura en inglés de Implicit Relational Assessment Procedure) hacia el suicidio (IRAP-HS), se utilizó el Inventario de Ideas Suicidas Positivas y Negativas (PANSI, abreviatura en inglés de Positive and Negative Suicidal Ideation) y la Escala de Desesperanza de Beck, aplicados a una muestra de 102 estudiantes de una universidad del Departamento de Nariño. Si bien los resultados encontrados en este trabajo carecen de la contundencia necesaria para plantearse la aplicabilidad clínica del IRAP-HS en el corto plazo, el comportamiento de las puntuaciones DIRAP (obtenidas mediante un proceso que busca contrarrestar los efectos de la variabilidad de los participantes relacionada con factores como la edad, la habilidad motriz y la inteligencia) en los diferentes grupos de comparación, definitivamente no permite descartar que la latencia de respuesta a los ensayos esté siendo afectada por el grado de coherencia entre la red verbal de los participantes y las relaciones especificadas en los arreglos contingenciales del procedimiento. Finalmente, se analizan algunas implicaciones de los resultados para la aplicabilidad del IRAP en la práctica clínica.

Abstract The purpose of the present study was to validate a standardized procedure for measuring attitudes towards suicide in university students. As the concurrent validation criteria for the Implicit Relational Assessment Procedure (IRAP) to suicide (IRAP-HS), the Positive and Negative Suicidal Ideas Inventory (PANSI) and the Beck Hopelessness Scale were administered to a sample of 102 students of the University of Nariño. Although the results found lack of a strong response to consider the clinical applicability of the IRAP-HS in the short term, the behavior of the DIRAP scores (obtained through a process that seeks to counteract the effects of participant variability related to factors such as age, motor skills and intelligence) in the different comparison groups does not definitively allow dismissing that the response latency to the trials is being affected by the degree of consistency between the verbal network of the participants and the relationships specified in the contingency arrangements of the procedure. Finally, some implications of the results for the applicability of IRAP-HS in clinical practice are analyzed.

A PCR-RFLP method for detection of the LNPEP encoding human insulin-regulated aminopeptidase (IRAP) rs4869317 polymorphism.

Background & objectives: Insulin regulated aminopeptidase (IRAP) has been related to certain pathologies such as breast cancer, Alzheimer´s disease and septic shock. IRAP is encoded by the leucyl/cystinyl aminopeptidase (LNPEP) gene. The genetic variation in the LNPEP gene has been analyzed in relation with the mortality and vasopressin clearance in septic shock. The LNPEP rs4869317 SNP (single nucleotide polymorphism) was the most significantly associated SNP with vasopressinase activity, being TT genotype associated with increased mortality. The objective of the present study was to develop a simple method to allow a quick and affordable genotyping for the rs4869317 SNP of LNPEP gene. Methods: Blood DNA samples were obtained from randomly selected healthy volunteers (n=28). A pair of primers was designed to amplify an 834 bp region of the LNPEP gene containing the rs4869317 SNP. The two alleles (T or A) were detected by digestion of the PCR products with the PacI restriction endonuclease. This enzyme only cuts the PCR products when the adenine is present in the SNP. Results: All individuals showed RFPL (restriction fragment length polymorphism) fragments for the expected genotypes (TT, TA or AA). The methodology was validated by sequencing of the amplified DNAs from several ‘T/T’ and ‘A/A’ homozygotes and ‘T/A’ heterozygotes. The results from both methods showed agreement. Interpretation & conclusions: The PCR-RFLP is a simple and reliable method that allows a quick genotyping for the rs4869317 SNP of LNPEP gene. The study of this polymorphism could be useful in future investigations to analyze the role of genetic variants of IRAP in several physiological/pathological conditions.

Genetic Diversity of Some Capparis L. Species Growing in Syria

This work investigated the genetic diversity and relationships among Capparis species growing in Syria using IRAP and ISSR techniques. Forty-seven samples of three Capparis species genotypes were collected from 21 different locations in Syria. The genotypes were morphologically identified based on the descriptions available in the literature. When IRAP technique was used, an average of 71.5% of the amplified fragments were polymorphic compared to 82.04% in ISSR. Morphological characterization along with the cluster and PCoA analyses of the data divided the studied genotypes into three groups. The groups included genotypes identified as Capparis spinosa L, C. sicula Duh., and C. aegyptia Lam. Based on the morphological description, molecular studies and statistical analyses of this study, C. aegyptia could be suggested as a separate species and not a varietal rank of C. spinosa (C. spinosa var. aegyptia (Lam.). Two samples (Alep1 and Idl) were not placed in any of the three distinctive groups, despite their closeness morphologically to C. spinosa. In PCoA analysis, sample Alep1 came between C. sicula and C. spinosa and Idl was placed between C. sicula and C. aegyptia. Although hybridization between Capparis species could occur, it was not clear from the present study if these two genotypes were hybrids.

Efficiency of IRAP and ITS-RFLP marker systems in accessing genetic variation of Pyrenophora graminea

The usefulness of IRAP (inter-retrotransposon amplified polymorphism) and ITS-RFLP (restriction of PCR-amplified internal transcribed spacers of the rDNA) markers in the analysis of 39 Pyrenophora graminea isolates was determined. Each marker system could discriminate between all of the isolates in detecting polymorphism, albeit with variable efficiency. IRAP and ITS-RFLP produced 85 percent and 77 percent polymorphic bands, respectively, with a corresponding mean polymorphic information content (PIC) of 0.38 and 0.36. The IRAP marker index ratio (2.41) was higher than ITS-RFLP (1.50). On one hand, the quality nature of data (QND) was higher for ITS-RFLP (0.169) than IRAP (0.093). However, correlation between both marker similarity matrices was significant (r = 0.34, p < 0.05). These findings suggest their combined use in phylogenetic analysis. To our knowledge, this is the first report of a comparison involving these two advanced DNA marker systems.

Evolutionary course of CsRn1 long-terminal-repeat retrotransposon and its heterogeneous integrations into the genome of the liver fluke, Clonorchis sinensis

The evolutionary course of the CsRn1 long-terminal-repeat (LTR) retrotransposon was predicted by conducting a phylogenetic analysis with its paralog LTR sequences. Based on the clustering patterns in the phylogenetic tree, multiple CsRn1 copies could be grouped into four subsets, which were shown to have different integration times. Their differential sequence divergences and heterogeneous integration patterns strongly suggested that these subsets appeared sequentially in the genome of C. sinensis. Members of recently expanding subset showed the lowest level of divergence in their LTR and reverse transcriptase gene sequences. They were also shown to be highly polymorphic among individual genomes of the trematode. The CsRn1 element exhibited a preference for repetitive, agenic chromosomal regions in terms of selecting integration targets. Our results suggested that CsRn1 might induce a considerable degree of intergenomic variation and, thereby, have influenced the evolution of the C. sinensis genome.