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La anastomosis de Blalock-Taussig modificada habitualmente se liga durante las sucesivas cirugias correctoras o paliativas de las cardiopatias congenitas subyacentes, aunque a veces se la mantiene permeable por diversas razones. A posteriori, cuando se considera que ya no es necesaria, se indica su oclusion, y actualmente la embolizacion percutanea con diversos coils o dispositivos es el metodo de eleccion. Comunicamos una serie de pacientes con este tipo de anastomosis ocluidas exitosamente desde un abordaje arterial con el nuevo dispositivo Amplatzer Vascular Plug que, ademas de tener un sistema de liberacion controlada, cuenta con la ventaja de que se puede implantar a traves de cateteres de pequeno calibre. Los pacientes eran de 1, 4 y 23 anos; no hubo complicaciones. Los tiempos de fluoroscopia fueron 10, 11 y 9 min respectivamente, con seguimiento hasta 42 meses.

Paraoxonase-1 (PON1) is a serum enzyme which catalyzes the hydrolysis of organophosphate pesticides. In this study we conducted a cross-sectional study and reported on the distribution of three common genetic polymorphisms of the PON1 gene in a population of floriculture workers from Mexico as well as the association between those polymorphisms and other predictors with serum PON1 activity on paraoxon, diazoxon and phenylacetate. The genotype frequencies at position PON1(55) were 89% (LL), 10% (LM) and 0.6% (MM), at position PON1(192) they were 16% (QQ), 47% (QR) and 37% (RR), and 26% (TT), 42% (TC) and 32% (CC) at position PON1(-108). Thus, the frequencies of alleles L, Q and T were 0.94, 0.40 and 0.47, respectively. The PON1(55) polymorphism had no significant effect on serum PON1 activity on any substrate. We found a significant association between the PON1(192) polymorphism and PON1 activity towards paraoxon and diazoxon, which increased in genotypes as follows: 192RR>192QR>192QQ for paraoxonase activity and, inversely, 192QQ>192QR>192RR for diazoxonase activity. The PON1(-108) polymorphism also had a significant effect on PON1 activity level towards paraoxon in the following order among the genotype groups: -108CC>-108TC>-108TT. Serum PON1 activity towards diazoxon was not associated with the PON1(-108) polymorphism but it was influenced by the intensity exposure to pesticides at the floriculture industry and the years of the occupational exposure to pesticides. No polymorphism significantly influenced serum PON1 activity on phenylacetate.

Rosiglitazone is an agonist of the peroxisome proliferator-activated receptor (PPAR) gamma that may modify HDL metabolism in humans, but this effect has not been completely elucidated. Therefore, we determined the effect of rosiglitazone on apo AI turnover, HDL structure, and PON1 plasma activity.Kinetic studies of HDL-apo AI radiolabeled with (125)I were performed in 7 chow-fed, male, New Zealand white rabbits after 6 weeks of 0.32 mg/kg/d rosiglitazone-treatment vs. vehicle-treated rabbits (n=11). HDL size distribution was determined by polyacrylamide gradient electrophoresis and paraoxonase-1 (PON1); plasma activity was assessed spectrophotometrically using phenylacetate as substrate.Fractional catabolic rate (FCR) of HDL apo AI was higher in the rosiglitazone-treated group than in the control group (0.031+/-0.004 vs. 0.025+/-0.006 pools/h, respectively, p0.05). The mean apo AI production rate (PR) was 62% higher in the rosiglitazone group as compared to controls (0.918+/-0.238 vs. 0.564+/-0.160 mg/kg/h, p0.01). Accordingly, apo AI plasma levels in rosiglitazone-treated animals were about 37% higher than in the control group. Rosiglitazone-induced changes in apo AI turnover appeared concomitantly with a significant increase of phospholipids and a decrease in colesteryl esters content of the HDL. Compositional changes resulted in a relative increase of the HDL3b and HDL3c subfractions and a significant enhancement of the plasma PON1 activity (488.5+/-138.2 vs. 595.2+/-179.4 micromol/min/ml, p0.05).Rosiglitazone increased apo AI plasma concentrations, resulting from an enhancement of apo AI synthesis, and induced the synthesis of smaller HDL particles with a concomitant increase of plasma PON1 activity. These modifications may contribute to the anti-atherogenic potential of rosiglitazone.

Background: Takayasu's arteritis (TA) is an idiopathic chronic inflammatory disease that causes occlusion of large arteries, but little is known about whether affected patients are characterized by endothelial dysfunction, different high-density lipoproteins (HDL) subclasses and paraoxonase-1 (PON1) activity. Methods and Results: In the present study, 30 patients with TA, 30 age- and gender-matched volunteers (controls) and 15 patients with essential hypertension were studied. Flow-mediated vasodilation (FMD) and maximal blood flow velocity, assessed in the brachial artery by high-resolution ultrasound, were significantly lower in patients. HDL subclass distribution was determined by polyacrylamide gradient gel electrophoresis. HDL-cholesterol, HDL3b subclass and PON1 activity, assessed spectrophotometrically using phenylacetate as the substrate, were also lower in patients compared with controls. In a multiple regression analysis, the use of prednisone and systolic blood pressure were independent variables that predicted the FMD. Conclusions: A low FMD, abnormal size distribution of HDLs, and low PON1 activity are observed in TA patients. These abnormalities appear independently and constitute a cluster that may contribute to the vascular dysfunction of TA arteritis. (Circ J 2009; 73: 760 - 766)

¿Cuán desigual es percibida la sociedad chilena por los ciudadanos? ¿Ha cambiado la imagen que los chilenos tienen de esa desigualdad en los últimos años? ¿Qué factores determinan los niveles de desigualdad percibidos? Utilizando datos provenientes de las encuestas del Centro de Estudios Públicos (CEP) abordamos estas preguntas. Los resultados muestran que los chilenos perciben mayoritariamente que viven en una sociedad desigual, que esas percepciones han variado poco entre 2000 y 2013, aunque mostrando un percepción levemente más positiva hacia 2013, y que los principales determinantes de esas percepciones son económicos y no políticos.

In 2015, a center-left government introduced an electoral reform that replaced the binomial electoral system governing parliamentary elections since 1989 with a more proportional system. This article provides an account of the reform process, describes the new electoral law, and discusses the factors explaining the reform. We argue, first, that it was possible, due to the incentives the government provided, to secure the support of an ample majority of parliamentarians; also, a new and favorable political scenario had emerged, in which the support of the main right-wing parties was not necessary for the reform to pass. Second, we maintain that the reform sought mainly to resolve problems affecting the parties of the governing coalition related to negotiations of coalition lists for elections. As a complementary objective, the reform promoted a general interest by establishing rules that allowed a “fairer” system of representation and improved competitive conditions.

Background and objective: Takayasu's arteritis is a disease that has been associated with tuberculosis, based upon the presence of Langerhans giant cells and granulomas. ATP treatment of mycobacteria infected macrophages induces apoptosis mediated via the P2X7 pathway. Here we evaluated if the polymorphisms of the P2X7 receptors are associated to the presence of tuberculosis in Mexican patients with Takayasu´s arteritis. Methods: 63 aortic samples, 33 from Takayasu´s and 30 from tuberculosis subjects were studied. Histological analysis was made and the sequence of the gene IS6110 which identifies the presence of Mycobacterium tuberculosis was amplified. Polymorphisms of the A1513C and -762 C/T receptors for the P2X7 gene were analyzed. Results: The analysis showed a high percentage of extra pulmonary lesions (36.3%) in the Takayasu´s group. No significant differences between the studied genotypes were found in any of the models analyzed or in any of the two P2X7 polymorphisms analyzed. Moreover, an increase in the 1513C allele in presence of IS6110 gene in the Takayasu´s group was observed when comparing with the group of tuberculosis. Conclusion: We found a high percentage of extra pulmonary tuberculosis in subjects with Takayasu´s arteritis; this increase was associated with a high frequency in the allele 1513C in the presence of IS6110 gene. Thus, these alleles may confer a significant susceptibility at the aortic level in the Mexican population having these diseases.

Between May 2003 and July 2006, we carried out percutaneous patent ductus arteriosus closure using a Nit-Occlud device in 28 patients, who had a median age of 1.8 years (range 0.5-21 years) and a median weight of 10.9 kg (range 5.9-64 kg). The ductus arteriosus had several different morphologic forms, and there was one postsurgical recanalization of the ductus arteriosus. The median minimum ductal diameter was 1.8 mm and the median maximum aortic ampulla diameter was 6.5 mm. The occlusion rate immediately after intervention was 53.5%, which increased to 95.2% by 12 months and to 100% by 18 months. The median follow-up time was 20.5 months. The Nit-Occlud device provided an effective and safe means of patent ductus arteriosus closure, irrespective of ductus morphology.

Paraoxonase gene polymorphisms (PON1-55 and PON1-192) were determined in four Mexican populations (Mestizos, Nahuas, Teenek and Mayos) belonging to different ethnic groups. The role of these polymorphisms in the lipid profile in the Mestizo group was also analyzed. PON1 polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism. Comparison among Mexican populations showed increased frequencies of PON1-55 L allele and LL genotype and decreased frequencies of M allele and LM genotype in the three Amerindian populations when compared to Mestizos (P < 0.05). Mexicans together with Asian populations (from Japan and China) presented the highest frequencies of PON1-55 L allele (P < 0.05 when compared to Caucasian populations). Heterogeneous data were noted when PON1-192 polymorphism comparison was made. In summary, distribution frequencies of PON1 showed that Mexican populations are more related to Asians than Caucasians. This confirms previous studies with other genetic markers indicating that Native Americans have stronger genetic affinities to the Paleolithic people of North-East Asia than to other major world populations. In Mexican Mestizos, lack of correlation between PON1 polymorphisms and lipid profile was found, corroborating previous data in other populations. The present data could be helpful to understand the distribution of these polymorphisms and its role as genetic and evolutive markers in the Amerindian populations.

Objetivo Presentar nuestra experiencia con el empleo de stent para mantener la permeabilidad ductal en cardiopatías congénitas dependientes del ductus. Método y resultados En tres pacientes de entre 2 y 9 días de vida con atresia pulmonar se colocaron cuatro stents por cateterismo, sin complicaciones. El tiempo de seguimiento promedio fue de 411 días (123 a 721 días). Dos stents se redilataron exitosamente. Un paciente fue sometido a cirugía, uno interrumpió sus controles cuatro meses después y otro espera cirugía. La saturación promedio aumentó del 61% al 80%. Conclusiones En pacientes con cardiopatías cuya circulación depende del ductus arterioso, el implante del stent fue factible y efectivo a corto y mediano plazos.

Objective: To investigate the role of HSP70 genes as contributors to genetic susceptibility of the spondyloarthropathies (SpA) in the Mexican population. Methods: The study included 150 patients with SpA (undifferentiated spondyloarthropathy (uSpA) 68, ankylosing spondylitis (AS) 60, and reactive arthritis 22) and 158 healthy controls. HSP70-1, HSP70-2 and HSP70-hom genotypes were analysed by the polymerase chain reaction-restriction fragment length polymorphism technique. Statistical methods included the Mantel-Haenzel, χ2, Fisher's exact test, and Woolf's method for odds ratio (OR). Results: HSP70-2 B/B genotype frequency was increased in the whole group of patients with SpA (pC

Takayasu’s arteritis (TA), of unknown etiology, has been related with Mycobacterium tuberculosis infection. The published cases are controversial. A 29- year-old man died, prolapse of the aortic valve and unspecific arteritis were demonstrated at necropsy. Our objective was to search in the fresh aortic tissues, the infectious agent of tuberculosis through culture, as well as by performing histopathology and searching by the molecular study, sequences of genes associated to micobacteria and Ziehl’s stain. Results. The bacillus of tuberculosis was observed by the Ziehl’s stain and the sequences of insertion IS6110 gene were identified. Our findings support the relation of TA with possible tuberculosis infection.Conclusion. The possibility that Takayasu’s arteritis is an extra pulmonary tu-berculosis must be explored.

The influence of apolipoprotein E (APOE) genotypes on plasma lipid levels was determined in 278 Mexican individuals. The most frequent genotype was E3/3 (80.5%) followed by E3/4 (12.5%), E2/3 (5.0%), E2/4 (1.4%), and E4/4 (0.3%). Our data are similar to those previously described for Mexican-American and American Indian populations, which show the highest frequency worldwide of the APOE*3 and the E3/3 genotype. Compared to female carriers of the E3/3 genotype, women with the E3/4 genotype presented increased low-density lipoprotein cholesterol (117 ± 28.0 mg/dL vs. 134.0 ± 31.7 mg/dL, p 0.05), and total cholesterol (179.4 ± 33.4 mg/dL vs. 197.5 ± 35.4 mg/dL, p 0.01). Also, we detected increased high-density lipoprotein concentrations in women with the E2/3 genotype (53.7 ± 19.5 mg/dL) when compared to women with the E3/3 genotype (45.2 ± 12.0 mg/dL) (p 0.032). Our data suggest that genetic variation at the APOE locus in the Mexican population is a genetic factor that influences plasma lipid levels. This effect was observed only in the female population. Additional studies attempting to correlate APOE polymorphism with plasma lipid profile in a large number of individuals would be helpful in establishing the true significance of this polymorphism in the Mexican population.

Takayasu arteritis (TA) is characterized by a ‘pulseless' condition and occurs frequently in young females from Asian and South American countries. It has been associated with Mayor Histocompatibility Complex (MHC) genes in different populations. Recent data indicate direct participation of HLA-B alleles in the susceptibility to the disease. This fact was explored in an associative study with TA to establish if some region in the exon 2, intron 2 or in the exon 3 of HLA-B alleles is common in the alleles associated with TA and at the same time to know if a specific sequence or an epitope, more than an allele, would be responsible for the susceptibility to this vasculitis. We studied HLA-B alleles of 12 Mexican patients with TA using PCR-SSP and sequencing. The analysis by PCR-SSP in 12 patients showed that five of them showed the B*15 allele, three the B*40 allele and two the B*39 allele, the remaining two presented the B*44 allele. Sequence analysis enabled us to define that the B*39 subtypes are B*3908; B*15 subtypes are B*1510, B*1515, B*1522 and B*1531; and the B*40 subtypes are B*4005 and B*4008. An individual with B*51 (B*5107) and another with B*52 (B*5201) alleles were also identified. The sequences of the intron 2 seem be heterogeneous. Analysis at the 63 and 67 positions of HLA-B alleles showed that 9 of them have similarity in some of these positions with the residues detected in the B*5201 and B*3902 alleles associated with TA in Asian populations. The results indicate that there is heterogeneity in the alleles associated with TA in Mexicans but, in spite of that heterogeneity, the alleles associates can be separated into three groups: B*39, B*15 and B*40, whose subtypes are rare and apparently of recent generation in Mexico, probably by recombination events at intron 2 level. The sequences analysis also shows that most of the alleles detected in the Mexican patients share two epitopes described in the susceptibility alleles in Asian populations, suggesting that these epitopes could be responsible for the susceptibility to develop the disease in spite of the allele in which are found.

La fístula coronaria congénita es una patología poco frecuente y en general asintomática, por lo que muchas veces se diagnostica por un hallazgo incidental. Con dependencia de la repercusión hemodinámica, algunos siguen una conducta conservadora, otros indican tratamiento quirúrgico o, más recientemente, oclusión por cateterismo.Se presenta el caso de una paciente con una gran fístula coronaria-cameral, que se trató mediante embolización percutánea con dispositivo Amplatzer vascular plug. No se presentaron complicaciones durante el procedimiento ni en el seguimiento.

Resena de libro: Victor Figueroa Clark , Salvador Allende: Revolutionary Democrat (London: Pluto Press, 2013), pp. x + 164, £12.99, pb. Articulo de publicacion ISI.

This paper focuses on the role of interest groups (IGs) in trade policy making process. In particular, it analyzes the participation of the IGs in the negotiations of the free trade agreements (FTAs) that Chile, Colombia and Peru signed with USA. Even though these negotiations have been studied from the perspective of the participation of IGs, until now there is neither a comparative analysis on this specific topic, nor those studies focus on the analytical factors that this study bases on. Thus, this research aims to make a contribution through a comparative analysis on the role of IGs in FTAs negotiations, establishing the similarities and differences among the three cases, and testing some hypotheses the academic literature has developed regarding this issue. The paper concentrates only on 3 specific issues related to it: 1) the objectives that each country pursued through a FTA with USA, and whether they were shared or not by IGs; 2) the relationship between government and IGs during trade negotiations; and 3) the potential influence of IGs on trade policy making.

Abdominal aortic pseudoaneurysm (AAP) is a rare lesion, although traumatic aortic injury is described as one of the main causes; both the rupture as the surgical treatment of the defect has high morbidity and mortality. Therefore, endovascular treatment either by chemical embolization or exclusion of defect with devices has emerged as an alternative treatment. However, there are risks such as occlusion of visceral vessels near the neck of the defect, embolization material or aortic rupture. Therefore, the choice of material and method of approach should be planned carefully in each case. We report a patient who ten years after abdominal wound firearm was diagnosed with AAP 17 x 13 cm, with short neck originated close to the ostium of the celiac trunk at an acute angle with the aortic axis. We perform the exclusion of the defect with a device designed for closing atrial septal defect from the left brachial access due to the angulation of the neck defect. There were no complications. At 72 hours was granted discharge. A month later, CT scan control showed the false aneurysm of equal size and no residual flow. The monitoring to date is five months and the patient remained asymptomatic.

Twenty cases of Dyphillobothrium pacificum (fish tapeworm) infections were prospectively studied to determine whether this tapeworm is associated with megaloblastic anemia, as commonly reported for D. latum infections. The most frequent symptoms were fatigue and mild abdominal pain, which were identified in approximately 66.6% of the 18 patients interviewed. Fourteen patients received treatment with niclosamide and all were cured. The other six patients spontaneously eliminated the tapeworms. One patient, who also had chronic diabetes and gastric atrophy, had low vitamin B12 levels and megaloblastic anemia. In all other patients, including three other patients with anemia, baseline vitamin B12 levels were in the reference range and did not significantly change when re-assessed three months later. Unlike D. latum, infection with D. pacificum is seldom associated with megaloblastic anemia or vitamin B12 deficit.

En este artículo se describen y analizan Ios principales acontecimientos sociales y políticos que marcaron el segundo año de gobierno de Sebastián Piñera. Como veremos, el 2011 estuvo marcado por un aumento significativo de procesos de movilización social que llevaron a la calle la expresión de sus demandas sociales, y que mostraron la incapacidad del gobierno y los partidos políticos en su conjunto de hacer frente a estos nuevos desafíos. Estos acontecimientos y sus consecuencias políticas son indicios de que el sistema político chileno puede estar cambiando, generando un alto grado de incertidumbre respecto a cómo ellos se desarrollarán en el futuro. This article describes and analyzes the main social and political events of the second year of Sebastián Piñeras government. The year 2011 showed a significant increase of social mobilization processes, that took to the streets the expression of social demands, showing the government' and political parties' inability to cope with these new challenges. These events and their political consequences are evidence of possible changes in the Chilean political system, producing a high level of uncertainty as to how they will develop in the future.

Low cholesterol and phospholipid plasma levels of some high-density lipoprotein (HDL) subclasses have been described in children with metabolic syndrome. Scavenger receptor class B type I (SR-BI) has been proposed to be at the origin of such HDL alterations because of its key role on cholesteryl esters-HDL metabolism. However, the possible contribution of SR-BI has not been specifically explored in this kind of patients.Plasma lipid concentrations of HDL subclasses, i.e., triglycerides (TG), phosphatidylcholine (Ph), free cholesterol (FC), and total cholesterol (TC), were determined by enzymatic staining on polyacrylamide gradient gels (PAGE) in 39 pediatric patients with metabolic syndrome and 65 children as controls. Cholesteryl esters were estimated by the difference between TC and FC. Proteins of HDL subclasses were also stained for the assessment of the relative size distribution of HDL. For statistical analysis, the study population was grouped by Srb1 +1050C--T polymorphism (rs5888) as carriers or noncarriers of the T allele, and data were corrected by metabolic syndrome status.The Srb1 +1050T allele was associated with metabolic syndrome [odds ratio (OR)=2.18 (1.12-4.22), P=0.02]. Plasma TG corresponding to HDL3a, as well as the relative proportion of this HDL subclass, were slightly higher in carriers of the T allele as compared to CC homozygous subjects. Cholesteryl esters plasma concentrations of all HDL subclasses were comparable between T allele carriers and noncarriers after correction by metabolic syndrome status.Srb1 +1050T was associated with metabolic syndrome, but T carrier subjects did not show important differences concerning HDL subclasses as compared to noncarriers.

This article analyzes the activity of the Chilean Congress since 1990 with regard to the fulfillment of its legislation and scrutiny functions as well as the reforms introduced to its normative framework, specially the constitutional reform of 2005. The objective of this paper, which is based on empirical data as well as legal analysis, is to deliver a broad vision about the role the Congress has played in the Chilean decision making process since the return to democracy. In particular, we argue that since 1990 the Congress has increased its capacity to influence the legislative domain as well as other domains such as the nomination of public authorities. At the same time, we argue that with the 2005 reform, the Congress possesses better scrutiny instruments, although their real effectiveness will be known only when we acquired better empirical information.

Background and Aims: Although there is evidence from animal studies of impaired reproductive function by exposure to OP, the effects on spontaneous abortion have not been sufficiently evaluated in ...

Resena de libro: El largo conflicto entre Chile y Bolivia. Dos visiones Luis Maira y Javier Murillo Santiago, Taurus, 2004, 196 pp

Este articulo analiza el proceso de interconexion gasifera entre Chile y Argentina, estudiando tres aspectos principales: a. Los objetivos de esta decision; b. La negociacion del Protocolo de 1995 y el rol desempenado en ella por los actores publicos y privados y c. Las «guerras de los gasoductos», que definieron las empresas que traerian el gas a Chile. En ese marco, se argumenta, primero, que el objetivo principal de la interconexion fue aumentar la competencia dentro del sistema electrico y diversificar la matriz energetica chilena. Segundo, que las caracteristicas del Protocolo y la evolucion reciente de Argentina indujeron a las autoridades y empresarios chilenos a pensar que en el futuro no habria problemas de suministro. Tercero, se discute como este caso pone de manifiesto las limitaciones del modelo chileno de Estado subsidiario.

Background Takayasu’s arteritis (TA) is a chronic inflammatory disease affecting the large arteries and their branches; its etiology is still unknown. In individuals suffering from TA, arterial inflammation progresses to stenosis and/or occlusion, leading to organ damage and affecting survival. Relation of TA with Mycobacterium tuberculosis has been known, but there have been only a few systematic studies focusing on this association. The IS6110 sequence identifies the Mycobacterium tuberculosis complex and the HupB establishes the differences between M. tuberculosis and M. bovis. Our objective was to search the presence of IS6110 and HupB genes in aorta of patients with TA. Methods We analyzed aorta tissues embedded in paraffin from 5760 autopsies obtained from our institution, we divided the selected samples as cases and controls; Cases: aortic tissues of individuals with Takayasu’s arteritis. Control positive: aortic tissues (with tuberculosis disease confirmed) and control negative with other disease aortic (atherosclerosis). Results Of 181 selected aorta tissues, 119 fulfilled the corresponding criteria for TA, TB or atherosclerosis. Thus 33 corresponded to TA, 33 to tuberculosis (TB) and 53 to atherosclerosis. The mean age was 22 ± 13, 41 ± 19, and 57 ± 10, respectively. IS6110 and HupB sequences were detected in 70% of TA tissues, 82% in tuberculosis, and in 32% with atherosclerosis. Important statistical differences between groups with TA, tuberculosis versus atherosclerosis (p = 0.004 and 0.0001, respectively) were found. Conclusion We identified a higher frequency of IS6110 and HupB genes in aortic tissues of TA patients. This data suggests that arterial damage could occur due to previous infection with M. tuberculosis.

Este articulo analiza la Jefatura de Gabinete de Ministros (JGM) en Argentina entre 1995 y 2007 con el fin evaluar su aporte como eventual mecanismo de “atenuacion” del sistema presidencial argentino. Del estudio se concluye, primero, que el diseno institucional de la JGM no es conducente a atenuar el presidencialismo, sino que mas bien apunta a eventualmente desconcentrar el poder presidencial. Segundo, se senala que en la practica la JGM no cumple esa funcion dada la continua modificacion de su estructura y atribuciones y la diferente posicion que los presidentes le han asignado. Y tercero, que por su diseno no es un mecanismo adecuado para superar la “rigidez” del presidencialismo.

Organophosphate pesticides are widely used in agricultural purposes. Recently, a few studies have demonstrated the ability of these chemicals to alter the function of the thyroid gland in human. Moreover, the paraoxonase-1 enzyme (PON1) plays an important role in the toxicity of some organophosphate pesticides, with low PON1 activity being associated with higher pesticide sensitivity. This study evaluates the interaction between exposure to organophosphate compounds and PON1 enzyme activity on serum levels of TSH and thyroid hormones in a population of workers occupationally exposed to pesticides. A longitudinal study was conducted on a population of floriculture workers from Mexico, during two periods of high and low-intensity levels of pesticide application. A structured questionnaire was completed by workers containing questions on sociodemographic characteristics and other variables of interest. Urine and blood samples were taken, and biomarkers of exposure (dialkylphosphates), susceptibility (PON1 polymorphisms and activity) and effect (thyroid hormone levels) were determined. Interaction between dialkylphosphates and PON1 polymorphisms or PON1 activity on hormone levels was evaluated by generalized estimating equation (GEE) models. A significant interaction was found between serum diazoxonase activity and total dialkylphosphates ({Sigma}DAP) on TSH levels. Thus, when PON1 activity was increased we observed a decrease in the percentage ofmore » variation of TSH level for each increment in one logarithmic unit of the {Sigma}DAP levels. This interaction was also observed with the PON1{sub 192}RR genotype. These results suggest a stronger association between organophosphate pesticides and thyroid function in individuals with lower PON1 activity.« less

Surgical closure of patent ductus arteriosus in adults involves a number of risks because there are associated anatomic and histologic alterations. Between October 1992 and August 2008, 23 patients were referred to our department with isolated patent ductus arteriosus. Their age ranged from 16-75 years (median 25.5 years) and their weight from 52-80 kg (median 57 kg). The pulmonary diameter ranged from 1.8-5.8 mm (mean 3.5 mm), and pulmonary artery pressure, from 9-72 mmHg (mean 15 mmHg). The rate of ductal occlusion achieved with the Rashkind patent ductus arteriosus occluder was 85.7%, and it was 100% with the Amplatzer duct occluder and the Nit-Occlud coil. The average hospitalization time and follow-up duration were 24 hours and 2 years, respectively. The only immediate complication was an inguinal hematoma, and there were no late complications. In adults, closure of patent ductus arteriosus using a number of different devices, especially the latest generation devices, was safe and effective, regardless of morphologic and histologic characteristics.

The ability of organophosphate pesticides to disturb thyroid gland function has been demonstrated by experimental studies on animal, but evidence of such effects on human remains scarce. The aim of this study was to assess the association between exposure to organophosphate compounds and serum levels of thyroid hormones in floriculture workers. A longitudinal study was conducted on 136 male subjects from the State of Mexico and Morelos, Mexico, occupationally exposed to organophosphate pesticides, during agricultural periods of high (rainy season) and low (dry season) levels of pesticide application. Using a structured questionnaire, a survey was carried out on sociodemographic characteristics, anthropometry, clinical history, alcohol and tobacco consumption, residential chemical exposure, and occupational history. Urine and blood samples were taken the day after pesticide application to determine urine dialkylphosphate (DAP) levels, serum levels of TSH, total T(3), total T(4), serum PON1 activity, and serum p,p'-DEE levels. The analysis of the association between DAP levels and thyroid hormonal profile was carried out using multivariate generalized estimating equation (GEE) models. Our results showed an increase in both TSH and T(4) hormones in serum associated with a increase in total dimethylphosphate levels (SigmaDMP) in urine (p-trend

article i nfo Background: Although there is evidence from animal studies of impaired reproductive function by exposure to organophosphates (OP), the effects on birth weight have not been sufficiently evaluated in epidemiological studies. Paraoxonase (PON1) detoxifies organophosphates by cleavage of active oxons. Some PON1 gene polymorphisms could reduce the enzyme activity and increase susceptibility to OP toxicity. Objective: To assess the association between maternal exposure to floriculture during pregnancy and the risk of low birth weight (b2500 g) in their offspring, as well as to evaluate the interaction between this exposure and maternal genotype for PON1 Q192R polymorphisms. Materials and methods: A cross sectional study was carried out in two Mexican states (States of Mexico and Morelos) with high frequencies of greenhouse activity. We interviewed and collected blood samples from 264 females (floriculturists or partners of floricultural workers) who became pregnant during the 10 years prior to the interview. The questionnaire measured socioeconomic characteristics, tobacco and alcohol consumption, diseases and occupational and reproductive history. We also applied a food frequency questionnaire. Information was obtained pertaining to 467 pregnancies. DNA was extracted from white cells, and PON1 genotype was determined by Restriction Fragment Length Polymorphism for Q192R polymorph- isms. Results were analyzed with generalized estimating equations models. Results: After adjusting for potential confounders, we detected a statistically significant interaction between maternal exposure to flower growing work during pregnancy and PON1 Q192R polymorphisms on risk of low birth weight. The risk of having a baby with LBW is nearly six times higher if a mother is a floriculture worker during pregnancy and has PON1 192RR genotype (OR 5.93, 95% CI 1.28, 27.5). Conclusion: These results suggest that the interaction between maternal floriculture work during pregnancy and 192RR PON1 genotype increases the probability of having children with LBW.

To determine the Paraoxonase-1 (PON1) activity as well as its pheno- and genotypes at position 192 in Mexican subjects with diagnosis of coronary heart disease (CHD).We determined the PON1-192 polymorphism by PCR-RFLP, and serum PON1 activity, using either paraoxon (PONase activity) or phenylacetate (ARE activity) as substrates, in 155 clinically healthy individuals (control group), and 155 patients with at least one myocardial infarction (CHD group). The biochemical A/B phenotype was determined by the ratio of the NaCI 1 M-stimulated PONase activity divided by the ARE activity.We found significantly lower PONase and ARE activities in CHD patients as compared to controls (233.1 +/- 102.1 vs. 295.8 +/- 159.1 nmol/min/mL, and 103.1 +/- 33.7 vs 220.2 +/- 120.7 micromol/min/mL, respectively, p0.05 for both). Allele and genotype frequencies for PON1-192 were similar in CHD patients and healthy controls. Moreover, in the control group, the PON1-192 Q/R genotype did not matched with the A/B phenotype as has been proposed by other studies.There were important differences in the ARE and PONase activities between Mexican CHD patients and controls, suggesting that PON1 activity could be a good marker of CHD risk, whereas PON1-192 lacks of value to assess such risk.

Este artículo aborda, a través del estudio del caso del Partido Socialista de Chile (PS), el tema del faccionalismo partidario en el sistema político chileno. En particular se sostiene, primero, que los grupos internos principales del PS pueden considerarse facciones, según las definiciones más utilizadas en la literatura comparada. Segundo, estudiamos la relación entre el sistema electoral binominal y el faccionalismo en el PS. Tercero, se analiza la relevancia de este faccionalismo en el proceso de toma de decisiones partidarias, argumentándose que existe una alta correlación entre el poder electoral interno de cada facción y el número de candidatos que ellas presentan en las elecciones de diputados. Esa correlación también es alta, cuando se trata de la conformación de gabinetes presidenciales.

We report the percutaneous closure of the pulmonary artery with residual shunt in patients with Fontan type circuit.Patients aged 9 and 11 years, with SaO2 of 88 and 96%, respectively. One of them coursing with headaches and functional class II. Both patients with total cavopulmonary anastomosis and fenestrated extracardiac conduit and permeable pulmonary artery (pulsatile Fontan). An Amplatzer duct-occluder device was implanted in the pulmonary artery entering from the femoral vein. Follow-up by means of clinical examination, imaging, and catetherization was pursued.Case 1, patency fenestration, Qp/Qs: 0.7/1. Case 2, closed fenestration, Qp/Qs; 1.3/1. We obtained immediate occlusion with 6/4 and 8/6 devices, respectively; pressure recordings revealed modification of the arterial morphology to biphasic; pulmonary pressure dropped 2 mm Hg in the first patient, without alteration in the second case; no changes in SaO2 were registered. Time of fluoroscopy was 57 and 45 minutes, respectively. Follow-up was maintained for 2.8 and 2.3 years, respectively. In patient 1, headaches disappeared and the fenestration was occluded with an Amplatzer septal-occluder one year later, raising SaO2 to 96%; no complications occurred nor was recanalization of the pulmonary artery needed in either case.Percutaneous occlusion of patent pulmonary artery in patients with Fontan type circuit is a feasible and effective procedure, and avoids overload of the single ventricle.

Background: Apolipoprotein E polymorphisms have important effects on plasma lipid levels and in the genetic susceptibility to development of cardiovascular diseases. Thus, the purpose of this study was to investigate the association of apolipoprotein E polymorphisms with coronary artery disease and with plasma lipid levels in a group of Mexican Mestizo patients. Methods: Apolipoprotein E polymorphisms were determined in 156 Mexican patients with coronary artery disease and 200 non-related healthy controls using the restriction fragment length polymorphism technique. The correlation of these polymorphisms with lipid profile (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides) in the patient group was determined. Results: A similar distribution of allele and genotype frequencies in coronary artery disease patients and healthy controls was found. Higher serum levels of high-density lipoprotein cholesterol and lower levels of low-density lipoprotein cholesterol, triglycerides and glucose were found in patients with the APOE*2/3 genotype when compared to patients with the APOE*3/4 and APOE*3/3 genotypes, although these differences were not significant. Conclusions: Our data suggest that genetic variation at the APOE is not a genetic factor related to the genetic susceptibility to coronary artery disease in Mexican individuals, but the role of this polymorphism in determining the lipid profile cannot be excluded.

Between May 2003 and July 2006, we carried out percutaneous patent ductus arteriosus closure using a Nit-Occlud device in 28 patients, who had a median age of 1.8 years (range 0.5-21 years) and a median weight of 10.9 kg (range 5.9-64 kg). The ductus arteriosus had several different morphologic forms, and there was one postsurgical recanalization of the ductus arteriosus. The median minimum ductal diameter was 1.8 mm and the median maximum aortic ampulla diameter was 6.5 mm. The occlusion rate immediately after intervention was 53.5%, which increased to 95.2% by 12 months and to 100% by 18 months. The median follow-up time was 20.5 months. The Nit-Occlud device provided an effective and safe means of patent ductus arteriosus closure, irrespective of ductus morphology.

Este artículo analiza presidenciales y parlamentarias chilenas de diciembre de 2005 y enero de 2006, centrándose en tres puntos principales. Primero, se estudia el surgimiento de las candidaturas presidenciales y la campaña presidencial, describiendo sus rasgos principales, argumentándose que la Concertación pudo retener la Presidencia luego que "politizó" la campaña, dejando de lado su estrategia inicial. Segundo, se analizan los resultados parlamentarios, destacándose la consolidación de la hegemonía de la UDI al interior de la Alianza y del pacto PS-PPD-PRSD en la Concertación. Por último, se hacen algunas observaciones sobre los eventuales efectos de estos resultados sobre el cuarto gobierno de la Concertación liderado por Michelle Bachelet This article analyzes the Chilean presidential and parliamentary elections held in December 2005 and January 2006, focusing on three main issues. First, we show how the presidential candidates emerged and the main characteristics of the presidential campaign. We argue that Concertación could retain the presidency after the campaign was politicized, leaving their original strategy behind. Second, we analyze the parliamentary results, showing the consolidation of UDI as the prime political party within Alianza and the consolidation of the PS-PPD-PRSD pact within the Concertación. Finally, we conclude with some notes on the potential effects of these results on the fourth Concertación' government lead by Michelle Bachelet

To evaluate the role of LMP (low molecular weight protein) genes as susceptibility markers for spondyloarthritis (SpA), LMP gene polymorphisms were analyzed in 223 Mexican patients with SpA (81 undifferentiated SpA [U-SpA], 117 with ankylosing spondylitis [AS], 25 with reactive arthritis) and in 139 ethnically matched healthy individuals. LMP genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism. The LMP2 and LMP7 allele frequencies were similar in patients and healthy controls. Genotype analysis revealed an increased frequency of LMP2 R/R genotype in the whole group of SpA (pC = 0.003, OR = 2.06, 95%CI = 1.3-3.25) and in the clinical subgroups of AS (pC = 0.039, OR = 1.88, 95%CI = 1.1-3.22) and U-SpA (pC = 0.003, OR = 2.56, 95%CI = 1.37-4.8) compared with healthy controls. Analysis in the LMP7 did not reveal significant differences in patients and healthy controls. The HLA-B27-negative AS subgroup also showed an increased frequency of LMP2 R/R genotype (pC = 0.027, OR = 4.81, 95%CI = 1.21-22.13). The LMP2-R/R AS patients were younger than LMP2-H/R and H/H patients at onset of the disease (16.0 +/- 6.8 years for R/R, 22.0 +/- 11.2 years for H/R and 28.6 +/- 10.9 years for H/H) (p0.05). The data suggest that, besides HLA-B27, LMP2 genotypes are also involved in the genetic susceptibility to develop AS in Mexicans. Furthermore, the age at onset of this disease might also be influenced by genotypes of this gene.

Low molecular weight polypeptide (LMP) genes are located within the major histocompatibility complex and have been associated with autoimmune diseases such as ankylosing spondylitis. In order to define the distribution of LMP genes in Mexican populations, the LMP2 and LMP7 polymorphism was analyzed in 312 Mexican individuals (95 Mexican Mestizos, 48 Nahuas, 56 Mazatecans, 50 Teenek, and 63 Mayos) belonging to different ethnic groups. In Mexican populations both Mestizos and Amerindians presented similar distribution of LMP2 and LMP7 polymorphisms, except Nahuas and Mayos who presented the higher frequencies of LMP2-H/H and the lowest frequencies of LMP2-H/R genotypes (P < 0.05 when compared with Mexican Mestizos). The LMP7-K/K genotype was absent in Nahuas, Teenek and Mayos and only one Mazatecan individual presented this genotype. Differences with other populations were found in Mexicans. An increased frequency of LMP2-H and a decreased frequency of LMP2-R alleles were observed in Mexican Amerindians (Nahuas and Mayos) when compared with Brazilian Amerindians (Kaingang and Guarani) and Caucasians (Spaniards) (P < 0.05). All Mexican populations (Mestizos and Amerindians) presented an increased frequency of LMP7-Q allele and a decreased frequency of LMP7-K allele when compared to Brazilian Amerindians (Kaingang), Caucasians (United States) and Asian (Japan) populations (P < 0.05). Genetic distances showed that Mexican Mestizos have an important relation with Spaniards and with all Mexican Amerindians. The present data corroborate the influence of Spaniard and Amerindian genes in the Mexican Mestizo population and could help to define the true significance of LMP polymorphism as genetic and evolutive marker in the Amerindian populations.

DRB1∗15/16 nucleotide polymorphism was analyzed in 68 DR2 positive individuals (18 Mexican Mestizos, 30 Mazatecans and 20 Nahuas), carrying a total of 75 DR2 haplotypes. HLA-DR2 was one of the most frequent specificities detected in Mazatecans and Nahuas with gene frequency (gf) of 0.232 and 0.141, respectively. In these populations DRB1∗16 was the most frequent DR2 split (gf = 0.183 in Mazatecans and gf = 0.135 in Nahuas), whereas in Mexican Mestizos the most frequent was DRB1∗15 (gf = 0.065). Four DRB1-DQB1 combinations in Mexican Mestizos, two in Mazatecans and one in Nahuas were in linkage disequilibrium. In spite of the restricted polymorphism, there were differences on DRB1∗15/16 alleles found in Mexicans. DRB1∗1501 a Caucasian allele was predominant in Mexican Mestizos, whereas DRB1∗1602 an Amerindian allele was characteristic on Indian populations. An important difference was detected among the Amerindian populations studied since DRB1∗1502 was only present in Mazatecans. This data corroborates the restricted polymorphism of DRB1∗15/16 and the high frequency of DRB1∗16 subtype in autochthonous American populations and suggest that the differences in gene frequencies of DRB1∗15/16 alleles could be helpful in distinguishing each of these population.

The major histocompatibility complex (MHC) genes are highly polymorphic and therefore have been useful in population genetics and disease association studies. We analyzed restriction fragment length polymorphism of HSP70-2 alleles in healthy unrelated Mestizo, Mazatecan and Nahua populations. Both Indian groups, Mazatecans and Nahuas, were in Hardy-Weinberg equilibrium, while Mestizos were in disequilibrium (chi 2 = 0.399; P < 0.05). The Mazatecan Indians presented a high frequency of BB homozygosity (17.35%) compared to Mestizos (5%) (P = 0.01). Mexican ethnic groups present differences in distribution of BB genotype. The low frequency of BB genotype in Mestizos may be the result of a negative selection process.