Online Cognitive-Behavioral Intervention on Adherence and Quality of Life in Elderly Adults with Diabetes: Two cases study

During the COVID-19 pandemic, elderly adults with type 2 diabetes mellitus (T2DM) have experienced difficulties to adhere to their therapy (TA), a situation which not only has had an impact on their glycemic control, but on their quality of life (QoL) as well. Telepsychology has proved to be an effective alternative to treat health-related complications in patients with this disease, however, results of same are unknown among the Latin American population. The aim of this study was determining the effect of Online Cognitive-Behavioral Therapy on TA, overall QoL and specific QoL in two elderly adults with T2DM. The case of a 62-year-old woman and a 60-year-old man who was offered an intervention consisting of nine sessions offered through a video conference platform is presented. The procedure included: psychoeducation, self-control training techniques, behavior reinforcement, feedback and problem solving. The Objective Clinical Change (OCC) evidences an increase in TA behaviors, such as use of medications, following a healthy diet (OCC≥ 0.20) and monitoring capillary blood glucose in the medium term (four months). Likewise, improve specific QoL for T2DM patients (OCC≤ -0.20). It is concluded that telepsychology is a low-cost, safe, feasible and effective type of therapy to increase and maintain TA behaviors, as well as to improve the QoL of patients suffering T2DM. Even though, more research is needed to increase the effectiveness of this therapy modality (AU)

Condición nutricional de escolares indígenas otomíes en situación de alta marginación / Nutritional status of indigenous Otomi schoolchildren in high marginal situation / Estado nutricional de população escolar de cultura indígena otomí em situação de alta marginalização

Resumen Introducción: El panorama de la salud y nutrición de la población mexicana se enmarca en la conjunción de desnutrición crónica infantil, sobre todo en el medio rural e indígena, y el incremento significativo del sobrepeso y obesidad. Esta información proveniente de encuestas arroja resultados generalizados, sin considerar las particularidades del contexto biosociocultural en que viven comunidades indígenas, codeterminante de la condición nutricional de éstas. Objetivo: Estudiar el estatus nutricional de un grupo de escolares de cultura otomí residentes en una comunidad de México en situación de marginación, considerando el contexto biosociocultural en el que viven. Métodos: Estudio prospectivo transversal realizado en una localidad del Estado de México. Muestra por conveniencia constituida por 214 menores, entre 6 y 12 años de edad. Se emplearon técnicas antropométricas internacionalmente aceptadas para recabar la estatura y el peso, y se calculó el IMC. El estatus de nutrición se estimó con base en el peso, la estatura y el IMC para la edad y se compararon con los referentes de la OMS. Resultados: La prevalencia de estatura baja para la edad y la desnutrición es menor, no así el sobrepeso/obesidad que afecta a un tercio de los menores. Solo para el IMC por edad y sexo hubo diferencias en ciertos grupos de edad. Las puntuaciones z de los tres indicadores son semejantes entre niños y niñas. Discusión y Conclusiones: En comparación con los parámetros nacional y estatal, los menores estudiados muestran prevalencia menor de sobrepeso y obesidad asociado a su contexto sociocultural.

Abstract Introduction: The health and nutrition outlook of the Mexican population may be framed in terms of chronic infant malnutrition, largely in the rural and indigenous sectors, and a significant increase in overweight and obesity. This general information is obtained from surveys without taking into account the biosociocultural context that is a codeterminant of the nutritional condition of many small indigenous communities. Objective: To study the nutritional status of Otomí school children living in a marginalized Mexican community from the perspective of the biosociocultural context in which they live. Methods: This is a prospective and transversal study carried out in a location of the state of México, México. The convenience sample was constituted by 214 children between 6 and 12 years old. Internationally accepted anthropometric techniques were used to collect data on the height and weight of these children. BMIs were calculated. The status of nutrition was estimated based on the expected weight, height, and BMI for each age. These data were compared with the corresponding WHO references. Results: The prevalence of low height and malnutrition related to the ages of these children was found to be low, but one in three of these children was found to be overweight or obese. There were some age groups differences regarding the BMI. The z scores of the three indicators are similar between boys and girls. Discussion and Conclusions: In comparison to the national and state parameters, the children studied showed a low prevalence of overweight and obesity associated with their sociocultural context.

Resumo Introdução: O panorama da saúde e nutrição da população mexicana se enquadra na conjunção de desnutrição infantil crónica, sobretudo no médio rural e indígena, e o incremento significativo do sobrepeso e obesidade. Esta informação vinda de enquetes gera resultados generalizados, sem considerar as particularidades do contexto biosociocultural em que vivem comunidades indígenas, co-determinante da condição nutricional destas. Objetivo: Estudar o estado nutricional de um grupo de escolares de cultura Otomí residentes em uma comunidade do México em situação de marginação, considerando o contexto biosociocultural em que vivem. Métodos: Estudo prospectivo transversal realizado em uma localidade do Estado do México. Amostra de conveniência constituída por 214 menores entre 6 e 12 anos de idade. Empregaram-se técnicas antropométricas internacionalmente aceitas para coletar a altura e o peso, e foi calculado o IMC. O estado de nutrição foi estimado com base no peso, a altura e o IMC para a idade e foram comparados com os referentes da OMS. Resultados: A prevalência da baixa altura para a idade e a desnutrição é menor, no entanto o sobrepeso/obesidade afeta a um terço dos meninos. Apenas para o IMC por grupos de idade e sexo houve diferenças em determinadas faixas etárias. As pontuações z dos três indicadores são semelhantes entre meninos e meninas. Discussão e Conclusões: Em comparação com os parâmetros nacionais e estaduais, os meninos estudados mostram menor prevalência de sobrepeso e obesidade associado ao seu contexto sociocultural.

Flattening of the orbital lower eyelid fat as a long-term outcome after surgical treatment of orbital floor fractures.

Our aim was to report the incidence of asymmetry of the lower eyelid (that manifests itself as flattening of the eyelid fat) as a long-term complication of the surgical approach of unilateral fractures of the orbital floor. We retrospectively reviewed the aesthetic appearance of the lower eyelid in 43 patients after repair of such fractures. Long-term asymmetry seen as asymmetrical flattening of the eyelid fat was evaluated and graded qualitatively as mild, moderate, and severe. We studied its relations to the surgical approach, patient's age and sex, and postoperative time; 20 of the 43 had flattening of the lower eyelid fat. There were significantly more patients with flattening of the fat after a transconjunctival approach than after transcutaneous ones (p=0.03). We found a statistical likelihood of the development of flattening of the fat when patients were between 40 and 60 years old at the time of operation (p=0.006). Increasing age at the time of the study was related to increased severity (p=0.0019), with the greatest significance over 55 years old (p=0.006). We found no relation to patients' sex, or duration of operation. To our knowledge this is the first time that flattening of the eyelid fat has been described as a long-term complication after a particular approach to orbital floor fractures. The transconjunctival incision was more likely to be associated with this long-term outcome. Patients over 40 years old are also at risk of developing flattening, and this is more severe when the patient is over 55. A short follow-up period is not sufficient for the evaluation of the aesthetic outcome of traditional approaches to fractures of the orbital floor in the lower eyelid.

Tratamiento quirúrgico de las lesiones del manguito de los rotadores.Controversia y evidencia / Surgical treatment of rotator cuff lesions. Controversy and evidence

La lesión del manguito de los rotadores es el síndrome doloroso más frecuente en la articulación del hombro. El tratamiento conservador ofrece resultados satisfactorios en la mayoría de los casos. No obstante, muchos pacientes no evolucionan de forma adecuada con las medidas conservadoras y requieren tratamiento quirúrgico. En el presente trabajo realizamos un repaso comparativo, basado en la evidencia disponible, de diferentes procedimientos relacionados con la reparación de las lesiones del manguito de los rotadores. Se abordan de forma crítica las ventajas e inconvenientes de los mismos, así como las posibles controversias que aparecen en la literatura científica

Rotator cuff injuries are the most frequent painful, shoulder joint disorders. Conservative treatments provide satisfactory results in the majority of cases, however, many patients do not evolve satisfactorily with these measures and require surgical intervention. The present study performed a comparative evidence-based review of the various procedures related to the repair of the rotator cuff lesions. A critical approach was used to investigate the advantages and disadvantages of the same together with any possible controversies reported in the literature

Tratamiento quirúrgico de las lesiones del manguito de los rotadores. Indicación y planificación preoperatoria / Surgical treatment of rotator cuff lesions. Indication and preoperative planning

La lesión del manguito de los rotadores es el síndrome doloroso más frecuente en la articulación del hombro. El tratamiento conservador ofrece resultados satisfactorios en la mayoría de los casos. No obstante, muchos pacientes no evolucionan de forma adecuada con las medidas conservadoras y requieren tratamiento quirúrgico. El objetivo de este trabajo es revisar las indicaciones quirúrgicas actuales, así como evaluar numerosos parámetros, tanto clínicos como radiológicos, que resultan fundamentales en la planificación de una intervención quirúrgica dirigida a la reparación de lesiones en el manguito de los rotadores

Rotator cuff injuries are the most frequent painful, shoulder joint disorders. Conservative treatments provide satisfactory results in the majority of cases, however, many patients do not evolve satisfactorily with these measures and require surgical intervention. The present study reviewed the surgical indications as well as the numerous radiological and clinical parameters that were fundamental when planning surgical interventions aimed at repairing rotator cuff lesions

Ethanol alters gene expression and cell organization during optic vesicle evagination.

Ethanol has been described as a teratogen in vertebrate development. During early stages of brain formation, ethanol affects the evagination of the optic vesicles, resulting in synophthalmia or cyclopia, phenotypes where the optic vesicles partially or totally fuse. The mechanisms by which ethanol affects the morphogenesis of the optic vesicles are however largely unknown. In this study we make use of in situ hybridization, electron microscopy and immunohistochemistry to show that ethanol has profound effects on cell organization and gene expression during the evagination of the optic vesicles. Exposure to ethanol during early eye development alters the expression patterns of some genes known to be important for eye morphogenesis, such as rx3/1 and six3a. Furthermore, exposure to ethanol interferes with the acquisition of neuroepithelial features by the eye field cells, which is clear at ultrastructual level. Indeed, ethanol disrupts the acquisition of fusiform cellular shapes within the eye field. In addition, tight junctions do not form and retinal progenitors do not properly polarize, as suggested by the mis-localization and down-regulation of zo1. We also show that the ethanol-induced cyclopic phenotype is significantly different to that observed in cyclopic mutants, suggesting a complex effect of ethanol on a variety of targets. Our results show that ethanol not only disrupts the expression pattern of genes involved in retinal morphogenesis, such as rx3 and rx1, but also disrupts the changes in cell polarity that normally occur during eye field splitting. Thus, ethylic teratology seems to be related not only to modifications in gene expression and cell death but also to alterations in cell morphology.

Pax2+ astrocytes in the fish optic nerve head after optic nerve crush.

The transcription factor Pax2 actively participates in the development of the vertebrate visual system. In adults, Pax2 expression persists in a subpopulation of Müller cells and/or astrocytes in the retina and optic nerve head (ONH), although its function remains elusive. In a previous work we showed that the pax2 gene expression is modified and the Pax2(+) astrocyte population in the ONH strongly reacted during the regeneration of the retina after a lesion in goldfish. In the present work we have analyzed Pax2 expression in the goldfish ONH after optic nerve (ON) crush. At one week post-injury, when the regenerating axons arrive at the ONH, the pax2 gene expression level increases as well as the number of Pax2(+) astrocytes in this region. These Pax2(+) astrocytes show a higher number of Cytokeratin (Ck)(+)/GFAP(+) processes compared with control animals. In contrast, a different S100(+) astrocyte population is not modified and persists similar to that of controls. Furthermore, we find a ring that surrounds the posterior ONH that is formed by highly reactive astrocytes, positive to Pax2, GFAP, Ck, S100, GS and ZO1. In this region we also find a source of new astrocytes Pax2(+)/PCNA(+) that is activated after the injury. We conclude that Pax2(+) astrocytes constitute a subpopulation of ONH astrocytes that strongly reacts after ON crush and supports our previous results obtained after retina regeneration. Altogether, this suggests that pax2 gene expression and Pax2(+) astrocytes are probably directly involved in the process of axonal regeneration.

NO dissociation on Cu(111) and Cu2O(111) surfaces: a density functional theory based study.

NO dissociation on Cu(111) and Cu(2)O(111) surfaces is investigated using spin-polarized density functional theory. This is to verify the possibility of using Cu-based catalyst for NO dissociation which is the rate limiting step for the NO(x) reduction process. The dissociation of molecularly adsorbed NO on the surface is activated for both cases. However, from the reaction path of the NO-Cu(2)O(111) system, the calculated transition state lies below the reference energy which indicates the possibility of dissociation. For the NO-Cu(111) system, the reaction path shows that NO desorption is more likely to occur. The geometric and electronic structure of the Cu(2)O(111) surface indicates that the surface Cu atoms stabilize themselves with reference to the O atom in the subsurface. The interaction results in modification of the electronic structure of the surface Cu atoms of Cu(2)O(111) which greatly affects the adsorption and dissociation of NO. This phenomenon further explains the obtained differences in the dissociation pathways of NO on the surfaces.

New insights into opioid regulatory pathways: influence of opioids on Wnt1 expression in zebrafish embryos.

Opioids are the most potent analgesics known today, but their prolonged administration produces severe adverse effects such as constipation, bradycardia, besides addiction, a concept not fully understood at present, which represents one of the most important challenges of modern bioscience. Wnts constitute an important family of vertebrate genes that encode secreted signaling proteins implicated in various developmental processes (patterning of the neural tube, neuronal differentiation), and are extensively conserved through evolution. In this study we have focused on Wnt1, an essential signal in axis polarity, as well as in proliferation and the development and differentiation of the CNS, roles shared by opioid receptors. Our previous studies in zebrafish show that morphine, the most potent analgesic known today, increases cell proliferation and induces neuronal protection and dopaminergic differentiation by activating the opioid receptors. The aim of the present study is to determine whether these effects are a consequence of an interaction between Wnt1 and the endogenous opioid system, which may act as a transcription regulator of Wnt1. Hence, we have exposed embryos to morphine, the endogenous delta opioid agonist Met-Enkephalin-Glu-Tyr (MEGY) (it binds with high affinity to both zebrafish delta opioid receptors, ZfDORs), and SNC80, a highly specific delta agonist, which displays low affinity towards the ZfDORs. Although at earlier stages, all opioids reduced the expression level of Wnt1, further on development, mainly during the differentiation of the CNS (24-48 h post fertilization (hpf)), morphine and MEGY increased Wnt1 expression. Our results point to the possibility that opioid signaling controls the transcription of Wnt1 and that through Wnt1, the opioid system regulates cell proliferation and neuronal differentiation. The present work opens a door to the discovery of new mechanisms that regulate opioid activity and its adverse effects, and hence, it might provide a good target to design new drugs that prevent or avoid these effects.

Pronóstico materno y perinatal en el embarazo con deficiencia del factor XII / Maternal and perinatal prognosis in pregnancy with factor XII deficiency

ANTECEDENTES: El déficit de factor XII es una enfermedad poco frecuente, relacionada con trombosis y abortos a repetición. OBJETIVO: Evaluar el resultado materno y perinatal en 25 embarazadas con déficit del factor XII. MÉTODOS: Estudio observacional descriptivo de 25 embarazadas (27 gestaciones) con esta patología desde enero 2005 a junio de 2011. RESULTADOS: La asociación de alteración del factor XII con otras trombofilias hereditarias o adquiridas es frecuente. En 24 mujeres se obtuvieron gestaciones exitosas, con sólo 3 abortos. Hubo 20 partos a término, con recién nacidos con peso y Apgar adecuado. Se registró un caso de restricción de crecimiento intrauterino. No hubo complicaciones médicas. Se utilizaron en todas las embarazadas antiagregantes y/o antitrombóticos como tratamiento. El fármaco utilizado más frecuente fue la heparina de bajo peso molecular, asociada en ocasiones al ácido acetilsalicílico. No hubo complicaciones por el uso de heparina de bajo peso molecular. CONCLUSIONES: El control multidisciplinar del embarazo y el tratamiento individualizado ha conseguido en esta patología buenos resultados maternos y neonatales.

BACKGROUND: The factor XII deficiency is a rare disease related with thrombosis and recurrent pregnancy loss. OBJECTIVE: To evaluate maternal and perinatal outcome in 25 pregnant women with deficiency of factor XII. METHODS: An observational descriptive study of 25 women with factor XII deficiency and pregnancy (27 pregnancies) between January 2005 and March 2011. RESULTS: The association with other inherited or acquired thrombophilia is common. 24 women have achieved successful pregnancies and only 3 miscarriages. There were 20 women with deliveries at term, with appropiate birth weight and Apgar test. There was one case of intrauterine growth restriction. There were no medical complications. The treatment used was antiplatelet and/or antithrombotic agents in all cases. The most used drug was low molecular weight heparin, sometimes associated to acetylsalicylic acid. CONCLUSIONS: A multidisciplinary control of the pregnancy and an individualized treatment has achieved good maternal and neonatal outcomes.

Cytoarchitectonic and neurochemical differentiation of the visual system in ethanol-induced cyclopic zebrafish larvae.

Embryonic exposure to ethanol leads to malformations such as cyclopia. Cyclopic embryos present fused eyes and lack of the ventral specification of the brain, with physiological and morphological defects in the visual system, which provides a useful model for teratology and neurotoxicity assessments. We analysed the differentiation of the visual areas in the ethanol-induced cyclopic animals. For this purpose we exposed zebrafish embryos to 1.5% ethanol from 4 hours post-fertilisation (hpf) to 24 hpf in order to get cyclopic embryos. We monitored cytoarchitecture and quantified both the proliferation rate and cell differentiation from 2 days post-fertilisation (dpf) onwards, focusing on the main components of the visual system (retina, optic nerve and optic tectum) of normal and cyclopic zebrafish embryos. The visual system of the zebrafish embryos is affected by exposure to ethanol; two optic nerves that fuse before leaving the eyes are present in cyclopic specimens but an optic chiasm is not evident. Cell differentiation is severely delayed throughout the visual system at 2 dpf. At 5 dpf, lamination in the cyclopic retina and optic tectum is completed, but they are filled with pyknotic nuclei demonstrating cell death. At this stage the proliferation rate and expression patterns are unaltered and glial and neuronal neurochemical differentiations are similar to untreated animals. We found that the alterations produced by exposure to ethanol are not only cell-selective, but also tissue-selective. Cyclopia is the most severe phenotype induced by ethanol, although cell differentiation and proliferation can reach normal patterns after a certain period of time, which points to a neural plasticity process. Zebrafish embryos may possess a compensation mechanism against the ethanol effect, which would account for their use for pharmacogenetic and chemical screenings in the analysis of new molecules that could improve visual problems.

Characterisation of neuronal and glial populations of the visual system during zebrafish lifespan.

During visual system morphogenesis, several cell populations arise at different time points correlating with the expression of specific molecular markers We have analysed the distribution pattern of three molecular markers (zn-1, calretinin and glial fibrillary acidic protein) which are involved in the development of zebrafish retina and optic tectum. zn-1 is a neural antigen expressed in the developing zebrafish central nervous system. Calretinin is the first calcium-binding protein expressed in the central nervous system of vertebrates and it is widely distributed in different neuronal populations of vertebrate retina, being a valuable marker for its early and late development. Glial fibrillary acidic protein (GFAP), which is an astroglial marker, is a useful tool for characterising the glial environment in which the optic axons develop. We describe the expression profile changes in these three markers throughout the zebrafish lifespan with special attention to ganglion cells and their projections. zn-1 is expressed in the first postmitotic ganglion cells of the retina. Calretinin is observed in the ganglion and amacrine cells of the retina in neurons of different tectal bands and in axons of retinofugal projections. GFAP is localised in the endfeet of Müller cells and in radial processes of the optic tectum after hatching. A transient expression of GFAP in the optic nerve, coinciding with the arrival of the first calretinin-immunoreactive optic axons, is observed. As axonal growth occurs in these regions of the zebrafish visual pathway (retina and optic tectum) throughout the lifespan, a relationship between GFAP expression and the correct arrangement of the first optic axons may exist. In conclusion we provide valuable neuroanatomical data about the best characterised sensorial pathway to be used in further studies such as teratology and toxicology.

Cyclic hardening in bundled actin networks.

Nonlinear deformations can irreversibly alter the mechanical properties of materials. Most soft materials, such as rubber and living tissues, display pronounced softening when cyclically deformed. Here we show that, in contrast, reconstituted networks of crosslinked, bundled actin filaments harden when subject to cyclical shear. As a consequence, they exhibit a mechano-memory where a significant stress barrier is generated at the maximum of the cyclic shear strain. This unique response is crucially determined by the network architecture: at lower crosslinker concentrations networks do not harden, but soften showing the classic Mullins effect known from rubber-like materials. By simultaneously performing macrorheology and confocal microscopy, we show that cyclic shearing results in structural reorganization of the network constituents such that the maximum applied strain is encoded into the network architecture.

Es posible la osteosíntesis mínimamente invasiva de la diáfisis del húmero sin riesgos? Estudio en el cadáver (técnica y anatomía) / Is risk-free minimally invasive humeral shaft osteosynthesis possible? A cadaver study (technique and anatomy)

Objetivos: Determinar la viabilidad de aplicar la técnica MIPPO (minimally invasive percutaneous plate osteosynthesis, “osteosíntesis percutánea con placa mínimamente invasiva”) en el tratamiento de las fracturas diafisarias de húmero, y observar las relaciones anatómicas de las distintas estructuras nobles con la placa de osteosíntesis. Introducción: Las fracturas de la diáfisis humeral representan el 1,6% del total de las fracturas quirúrgicas. La reducción abierta y la osteosíntesis con placa a compresión es un método aceptado universalmente pero, al requerir una disección extensa, hay posibilidades de dañar el nervio radial; otra alternativa es el uso de clavos intramedulares, pero el porcentaje de complicaciones es similar. Material y método: Para esto, se realizó un estudio en 5 cadáveres. Se procedió a realizar un miniabordaje deltopectoral en la zona proximal y se realizó la incisión distal a unos 5 cm, proximal a la flexura del codo en la región inferoexterna del brazo. Una vez realizados los 2 miniabordajes, se procedió a realizar un túnel subraquial anterior extraperióstico con un objeto romo, siempre por la cara anterior del húmero, y se introdujo una placa recta estrecha de 10 orificios de proximal a distal. Resultados: Una vez realizada la osteosíntesis, se procedió a identificar la relación de las distintas estructuras anatómicas con la placa prolongando ambas incisiones: no se encontró ninguna estructura anatómica noble en la cara anterior del húmero que pudiera dañarse. Conclusiones: Aunque pueda ser técnicamente difícil, la técnica MIPPO descrita aquí es menos invasiva y traumática que la reducción abierta y la colocación de una placa, además no supone riesgos especiales de lesión en el nervio radial o musculocutáneo (AU)

Purpose: To determine the feasibility of using minimally invasive percutaneous plate osteosynthesis (MIPPO) in the treatment of humeral shaft fractures and analyze the anatomical relations of the different bodily structures with the fixation plate. Introduction: Humeral shaft fractures account for 1.6% of all surgical fractures. Open reduction and compression plate fixation is a universally accepted method, but since it requires an extended dissection it could cause a lesion to the radial nerve. Another alternative is to use intramedullary nails, but the percentage of complications associated to them is similar. Materials and methods: We conducted a study of 5 cadavers. At the proximal level, we carried out a deltopectoral mini approach; the distal incision was performed at about 5 centimeters proximally to the elbow flexure in the inferomedial region of the arm. Once the two mini approaches were completed, a blunt instrument was used to drive an anterior extraperiosteal subbrachial tunnel on the anterior aspect of the humerus through which a 10-hole straight narrow plate was introduced from proximal to distal. Results: Once the osteosynthesis was completed, we identified the relationship of the different anatomical structures with the plate, extending both incisions without finding any significant anatomical structure on the anterior aspect of the humerus that could be damaged. Conclusions: Even if technically challenging, the MIPPO technique described herein is less invasive or traumatic than open reduction and plate fixation, and it is not associated with any special risks of injury to the radial or musculocutaneous nerves (AU)

Effect of gender and school level on disordered eating behaviours and attitudes in Mexican adolescents.

The aim of this study was to assess eating behaviours and attitudes in a community sample of 615 adolescent Mexican students recruited at a middle school (192 boys and 226 girls; mean age +/- standard deviation 13.56+/-0.09) and high school (90 boys and 107 girls; mean age 16.04+/-0.12 years), who completed the Eating Attitudes Test (EAT), the Bulimia Test (BULIT) and the Body Shape Questionnaire (BSQ). Multiple analysis of variance revealed the significant effect of gender on the negative feelings, body dissatisfaction, drive of thinness and perceived social pressure subscales, and school level on the body dissatisfaction and food preoccupation subscales. Among the high school girls, the gender x school level interaction had a significant effect on negative feelings, body dissatisfaction, drive of thinness, food preoccupation and perceived social pressure subscales. These data support previous findings concerning gender, and also suggest that perceived social pressure in the case of girls and food preoccupation in the case of boys could be important factors in the natural development of eating disorders.

Tópicos en investigación clínica: la pregunta de investigación / Topics on clinical research: the research question

El proceso de la investigación en epidemiología requiere el reconocimiento de los elementos que lo constituyen, con el fin de alcanzar un desarrollo exitoso del mismo. Algunos de estos temas no son de fácil abordaje para el investigador clínico, que necesita guías claras para lograr reflejar sus preguntas en estudios clínicos. El siguiente artículo es el primero de una serie de documentos que presentarán los tópicos más importantes en investigación y epidemiología clínica iniciando con el tema de la pregunta de investigación.

Achievement of a succesful epidemiological research process requires knowledge on the elements comprised in it. Some of these matters are not easy to approach by the clinical researcher who needs clear guidelines to be able to reflect his questions in clinical trials. This article is the first of a series of documents that will present major topics in research and clinical epidemiology starting with the research question.

Characterization of NADPH-diaphorase-positive glial cells of the tench optic nerve after axotomy.

NADPH-diaphorase (ND) positive cell types were characterized throughout the optic nerve of the tench in normal conditions and after optic nerve transection with survival periods of 1, 3, 7, 14, 30, 60, 120 and 180 days. Astrocytic markers (S100 and glutamine synthetase) and the microglial marker tomato lectin were employed. In the control prechiasmatic optic nerve two types (types I and II) of ND-positive glial cells appeared. All type I cells showed S100 immunoreactivity, whereas only a subpopulation of them were positive to glutamine synthetase. Type II cells only presented S100 immunoreactivity. In the control anterior optic tract, all ND-positive glial cells (type III) presented immunolabeling to S100 and glutamine synthetase. After transection, types I and II did not show any changes in the staining patterns for the glial markers when observed. Two new types of ND-positive glial cells (types IV and V) were observed after axotomy. All type IV cells were S100-immunopositive, and a subpopulation presented glutamine synthetase immunolabeling. Only a subpopulation of type V cells showed glutamine synthetase immunostaining. The presence of type IV or V cells in the lesioned optic nerve occurred simultaneously with significant decreases or absence of type I cells. These data suggest that type I and III cells are astrocytes and type II cells are oligodendrocytes. Types IV and V cells are the result of the activation of type I cells after optic nerve section. The polymorphism observed in ND-positive cells may reflect different cell functions during degenerative and regenerative processes.

Stress dip under a two-dimensional semipile of grains.

The origin of stress dip under the apex of a standard sandpile has stimulated significant debate within the scientific community. On the other hand, it could be argued that a semipile built against a vertical wall is of more practical interest since it serves as a model of dams, dykes, and embankments. There is surprisingly little information available for the stress distribution in this case. Here we show clear experimental evidence that the presence of the wall enhances the dip under a granular pile significantly. Our investigation provides insight into the influence of walls on the orientation of force chains and this appears to be key in enhancing the dip. Moreover, numerical simulations and experiments with different kinds of particles show that the vertical wall induces an alignment of isotropic particles.

Anomalous diffusion in silo drainage.

The silo discharge process is studied by molecular dynamics simulations. The development of the velocity profile and the probability density function for the displacements in the horizontal and vertical axis are obtained. The PDFs obtained at the beginning of the discharge reveal non-Gaussian statistics and superdiffusive behaviors. When the stationary flow is developed, the PDFs at shorter temporal scales are non-Gaussian too. For big orifices a well-defined transition between ballistic and diffusive regime is observed. In the case of a small outlet orifice, no well-defined transition is observed. We use a nonlinear diffusion equation introduced in the framework of non-extensive thermodynamics in order to describe the movements of the grains. The solution of this equation gives a well-defined relationship (gamma = 2/(3 - q)) between the anomalous diffusion exponent gamma and the entropic parameter q introduced by the non-extensive formalism to fit the PDF of the fluctuations.

Teratogenic effects of ethanol exposure on zebrafish visual system development.

Ethanol intake during pregnancy can produce a wide range of adverse effects on nervous system development including fetal alcohol syndrome (FAS). The most severe congenital malformation observed in newborns with FAS is cyclopia. In this study, we have exposed zebrafish embryos to different ethanol concentrations (2.4%, 1.5% or 1.0%) during eye morphogenesis in four zebrafish strains (AB, EK, GL and TL). In addition, we have studied the survival rate of the cyclopic animals to the end of larval development. The zebrafish strains GL and AB generated the higher percentage of cyclopic animals after exposure to 2.4% ethanol, while EK showed the higher percent cyclopic animals using 1.5% and 1.0% ethanol. The EK strain showed the higher percent survival during the larval period at all ethanol concentrations (2.4%, 1.5% and 1.0%). Moreover, we have investigated cytoarchitectural alterations in the main components of the visual pathway-retina and optic tectum-and ethanol treatment affects both the retina and the optic tectum. The lamination of neural retina is clearly delayed in treated larvae 3 days postfertilization and the thickness of the pigmented epithelium is considerably reduced. With regard to the optic tectum, treatment with ethanol alters the normal pattern of tectal lamination. The use of zebrafish EK strain is a suitable in vivo vertebrate model system for analyzing the teratogenic effect of ethanol during vertebrate visual system morphogenesis as it relates to both cyclopia and FAS.