First biochemical and behavioural analysis of the response of the scorpion Urophonius brachycentrus (Thorell: 1876) upon exposure to an organophosphate.

Scorpionism is an increasing public health problem in the world. Although no specific methodology or product is currently available for the control of those arachnids, the use of insecticides could be an effective tool. Chlorpyrifos is one of the insecticides used, but to date, whether scorpions recognise surfaces with that insecticide and how it affects their physiology and/or biochemistry is unknown. In the present study, we observed that scorpions recognise surfaces with 0.51 and 8.59 µg/cm2 of chlorpyrifos and avoid those areas. The 0.51 µg/cm2 concentration produced a decrease in acetylcholinesterase and an increase in catalase, superoxide dismutase and glutathione S-transferase, whereas the 8.59 µg/cm2 concentration evoked a decrease in acetylcholinesterase and an increase in catalase and glutathione S-transferase. Using the comet assay, we observed that the insecticide at 0.17, 0.51 and 8.59 µg/cm2 caused DNA damage. Finally, we found that the insecticide does not generate significant variations in glutathione peroxidase, glutathione reductase, the amount of protein or lipid peroxidation. The present results offer a comprehensive understanding of how scorpions respond, both at the biochemical and behavioural levels, when exposed to insecticides.

Detection and Identification of Phytoplasmas in the 16SrIV-A, -B, and -D Subgroups in Palms in Tabasco, Mexico.

The 16SrIV-A phytoplasmas are associated with the devastating disease lethal yellowing (LY) of palms. In Tabasco (Mexico), the death of Cocos nucifera, Adonidia merrillii, and Attalea butyracea palms have been suspected to be associated with LY based on symptomatology. Samples from the trunk of both symptomatic and nonsymptomatic palms were collected in three different environments: two species of palms within a rural zone and the other within an urban zone. DNA was extracted to perform a nested PCR with phytoplasma primers P1/P7-LY16SF/R16R2. A 1,345-bp fragment was amplified from the DNA extracted from each of the 29 LY-symptomatic palms sampled. Phytoplasma identification was achieved by amplicon sequencing and virtual restriction fragment length polymorphism analyses. Three 16SrIV phytoplasma subgroups were detected: 16SrIV-A in C. nucifera, 16SrIV-B in A. merrillii, and 16SrIV-D in C. nucifera, A. merrillii, and A. butyracea. Phylogenetic analysis showed also that the three phytoplasma strains found in the palm species clustered with phytoplasmas reported in the literature in the three subgroups identified. This is the first report of phytoplasmas associated with these palm species in Tabasco.

Low prevalence of most frequent pathogenic variants of six PARK genes in sporadic Parkinson's disease.

Genetic variants that confer susceptibility to Parkinson's disease (PD) show unbalanced distribution among different populations; genetic predisposition to either familial or sporadic forms of PD in Mexican-mestizo population has not been comprehensively studied. The aim of the present study was to analyze genetic variants in six PARK genes in PD patients. In total 381 individuals (173 patients, 208 controls) were genotyped for p.Gly2019Ser and p.Gly2385Arg variants of LRRK2. The p.Gly2019Ser variant was present in two patients and one healthy control; the p.Gly2385Arg variant was not found. In a subgroup of early-onset PD (EOPD), MLPA analysis was done for PARKIN (PARK2), PINK1 (PARK6), DJ-1 (PARK7), LRRK2 (PARK8), SNCA (PARK1/4) and ATP13A2 (PARK9). We found a heterozygous deletion of exon 2 in PARK2 in the youngest patient of the early-onset group, who showed limited response to antiparkinsonian therapy. Although the changes Gly2019Ser and Gly2385Arg of LRRK2 are associated with PD in different populations; they may be a rare cause of PD in our population. Novel population-specific variants may underlie PD susceptibility in Mexican mestizos. Our study suggests that the heterozygous deletion of exon 2 in the PARK2 gene is a risk factor for EOPD.

[Diversity of insects captured by weaver spiders (Arachnida: Araneae) in the cocoa agroecosystem in Tabasco, Mexico]. / Diversidad de insectos capturados por arañas tejedoras (Arachnida: Araneae) en el agroecosistema cacao en Tabasco, México.

The aim of this work was to know the diversity of insects captured by weaver spiders in a plantation of cocoa (Theobroma cacao L.) of 6 ha in the State of Tabasco, Mexico. The study was carried out from July 2004 to June 2005 by means biweekly samples of the insects captured on the spiders webs. The total of 3,041 webs of 54 species of spiders belonging to seven families (Araneidae, Theridiidae, Tetragnathidae, Uloboridae, Pholcidae, Dyctinidae and Linyphiidae) were revised. We found 1,749 specimens belonging to 10 orders of insects, represented by 93 families, the majority of Coleoptera, Diptera and Hemiptera that constituted 74% of the identified families. The biggest number of specimens of all orders was captured by Araneidae, except of Isoptera, whose specimens were captured mainly by the family Theridiidae. The index of diversity (H'), evenness (J') and similarity (Is), applied to know the diversity of families of insects captured among families of spiders, varied from 0.00 to 3.24, 0.00 to 0.81, and 0.04 to 0.522, respectively. We conclude that there is a wide diversity of insects predated by the weaver spiders in the cocoa agroecosystem, and that there are species that can be promising for the biological control of pests.

Monocytes modulate the in vitro basal frequency of sister chromatid exchanges of plasma leukocyte cultures and mitotic activity of suppressor-cytotoxic T8 human lymphocytes.

The effect of monocytes (MNs) on baseline SCEs and kinetics of human lymphocytes in plasma leukocyte (PLCs) and whole blood cultures (WBCs) was studied. Baseline SCEs in PLCs were nearly two-fold over WBCs. No differences in SCEs were observed between PLCs and MN-depleted PLCs, indicating that SCEs from PLCs are independent of MNs. MNs titration into PLCs decreased proportionally SCEs. Reconstitution of depleted PLCs with concentration of MNs equivalent or higher than those of PLC decreased SCEs. No variations of lymphocyte kinetics in PLCs were observed in the absence/presence of MNs. The proportion of B and T-cell subsets among interphasic lymphocytes were similar in PLC in the absence/presence of MNs, but a significant increase in the proportion of mitotic T8 lymphocytes was observed. Accordingly, MNs modulate both the in vitro basal SCEs and the mitotic activity of T8, but not their cell-cycle kinetics.

Diversidad de insectos capturados por arañas tejedoras (Arachnida: Araneae) en el agroecosistema cacao en Tabasco, México / Diversity of insects captured by weaver spiders (Arachnida: Araneae) in the cocoa agroecosystem in Tabasco, Mexico

El objetivo de este trabajo fue el de conocer la diversidad de insectos capturados por arañas tejedoras en una plantación de cacao de 6 ha en Tabasco, México. El estudio se realizó de Julio del 2004 a Junio del 2005 mediante recolectas quincenales de los insectos capturados en las telas de las arañas. Se revisaron 3,041 telas de 54 especies de arañas pertenecientes a siete familias (Araneidae, Theridiidae, Tetragnathidae, Uloboridae, Pholcidae, Dyctinidae y Linyphiidae) que capturaron 1.749 insectos de 10 órdenes, representados por 93 familias, la mayoría de Coleoptera, Diptera y Hemiptera que en conjunto constituyeron el 74 por ciento del total de las familias identificadas. La familia Araneidae fue la que capturó el mayor número de individuos de todos los órdenes, excepto de Isoptera, cuyos individuos fueron capturados principalmente por la familia Theridiidae. Los índices de diversidad (H'), equitatividad (J') y similitud (Is), aplicados para conocer la diversidad de familias de insectos capturados entre familias de arañas, variaron de 0,00 a 3,24, 0,00 a 0.81, y 0,04 a 0,522, respectivamente. Concluimos que existe una amplia diversidad de insectos que son depredados por las arañas tejedoras en el agroecosistema cacao y que hay especies que pueden ser promisorias para el control biológico de plagas.

The aim of this work was to know the diversity of insects captured by weaver spiders in a plantation of cocoa (Theobroma cacao L.) of 6 ha in the State of Tabasco, Mexico. The study was carried out from July 2004 to June 2005 by means biweekly samples of the insects captured on the spiders webs. The total of 3,041 webs of 54 species of spiders belonging to seven families (Araneidae, Theridiidae, Tetragnathidae, Uloboridae, Pholcidae, Dyctinidae and Linyphiidae) were revised. We found 1,749 specimens belonging to 10 orders of insects, represented by 93 families, the majority of Coleoptera, Diptera and Hemiptera that constituted 74 percent of the identified families. The biggest number of specimens of all orders was captured by Araneidae, except of Isoptera, whose specimens were captured mainly by the family Theridiidae. The index of diversity (H'), evenness (J') and similarity (Is), applied to know the diversity of families of insects captured among families of spiders, varied from 0.00 to 3.24, 0.00 to 0.81, and 0.04 to 0.522, respectively. We conclude that there is a wide diversity of insects predated by the weaver spiders in the cocoa agroecosystem, and that there are species that can be promising for the biological control of pests.

Linfoma primario de seno. Presentacion de un caso

El linfoma es una entidad muy rara como cuasa de lesiones malignas primariamente originadas en el seno. Igualmente, dentro de los linfomas de origen extradonal, el linfoma originado en el seno es uno de los más frecuentes. Sin embargo es importante establecer su diagnóstico, debido a la diferencia tanto en la modalidad terapéutica como en el pronóstico a largo plazo que tienen los pacientes con esta entidad, comparados con otros tipos de lesionesa malignas de seno. Este artículo presenta un caso clínico y revisa la literatura correspondiente en cuanto a frecuencia, clasificación, características clínicas, tratamiento y pronóstico del linfoma primario de seno.

Prevalencia de la mutacion del factor V de la coagulacion (factor V Leiden) en donantes de banco de sangre en cuatro ciudades colombianas / Mutation of factor V of coagulation

Introducción: la resistencia a la proteína C activada es el factor de riesgo genético más frecuente en los casos de tromboembolismo en la población caucásica, siendo responsable de aproximadamente 20 a 60 por ciento de los casos de trombofilia familiar. La sustitución de arginina (R) por ácido glutámico (Q) en la posición 506 del factor V de la coagulación, mutación denominada factor V Leiden, se encuentra en 95 por ciento de los casos de resistencia a la proteína C activada. Estudios en diferentes poblaciones alrededor del mundo han demostrado que esta mutación se encuentra restringida a las poblaciones con origen o mezcla de genes caucásicos. Objetivo: determinar la prevalencia de la mutación del factor V de la coagulación (factor V Leiden) en donantes de banco de sangre de cuatro ciudades colombianas. Material y métodos: en este estudio fueron genotipificados 495 individuos seleccionados dentro de un grupo de donantes de banco de sangre, distribuidos de la siguiente manera: 370 de Santafé de Bogotá, 50 de Barranquilla, 45 de Bucaramanga y 30 de Medellín. Resultados: se encontró una prevalencia del factor V Leiden de 1,44 por ciento en la población estudiada. Conclusión: la mutación del factor V, factor V Leiden, se encuentra presente en la muestra estudiada, y es un riesgo que debe ser investigado en pacientes con trombosis idiopática