Kinematic analysis of a lower limb to determine the center of rotation of the knee at the sagittal plane.

En esta investigación se establece una metodología que permite describir el movimiento de miembros inferiores usando cadenas cinemáticas cerradas. Este análisis es realizado con el objetivo de determinar la posición del centro de rotación (CR) de la rodilla localizado en el plano sagital. Un paciente sano y sin antecedentes patológicos realizó pruebas de flexión-extensión con uno de sus miembros inferiores. Cuando el paciente realizo el movimiento articular (la flexo-extensión) un dispositivo de video y un programa (World In motion v4.0) determinan la posición de cuatro marcadores pasivos ubicados en el miembro inferior. Los datos obtenidos de los marcadores son utilizados en un modelo propuesto que permite localizar la posición del CR de la rodilla. En este estudio se concluye que el CR de la rodilla presenta movimiento relativo respecto a un punto fijo marcado en un miembro inferior. Los resultados comprueban que el CR de la rodilla delimitado en el plano sagital no presenta comportamiento de una junta completa (junta con un grado de libertad) como ha sido presentado en otros estudios. Abstract A methodology is established in this research which permits to describe the movement of a lower limb using closed kinematic chains. This analysis is developed with the aim to determine the location of the center of rotation (CR) of the knee joint in the sagittal plane. Flexion-extension tests were carried out on one of the lower limbs of a healthy patient without pathological antecedents. When the patient does articular movement (flexion-extension), a video equipment and a software determine the position of four passive markers installed on the lower limb. The information obtained from the markers is applied to the proposed model which allows to locate the center of rotation of the knee joint. Hence it was concluded that the CR of the knee joint undergoes a relative movement with respect to the fixed point marked on the lower limb. The results prove that the knee joint established in the sagittal plane does not show the behavior of a complete joint (a joint with one degree of freedom) as it has been described in other studies

The transcription factor Slug represses E-cadherin expression and induces epithelial to mesenchymal transitions: a comparison with Snail and E47 repressors

13 pages, 7 figures.Transcriptional repression mechanisms have emerged as one of the crucial processes for the downregulation of E-cadherin expression during development and tumour progression. Recently, several E-cadherin transcriptional repressors have been characterized (Snail, E12/E47, ZEB-1 and SIP-1) and shown to act through an interaction with proximal E-boxes of the E-cadherin promoter. We have analyzed the participation of another member of the Snail family, Slug, and observed that it also behaves as a repressor of E-cadherin expression. Stable expression of Slug in MDCK cells leads to the full repression of E-cadherin at transcriptional level and triggers a complete epithelial to mesenchymal transition. Slug-induced repression of E-cadherin is mediated by its binding to proximal E-boxes, particularly to the E-pal element of the mouse promoter. Detailed analysis of the binding affinity of different repressors to the E-pal element indicates that Slug binds with lower affinity than Snail and E47 proteins. These results, together with the known expression patterns of these factors in embryonic development and carcinoma cell lines, support the idea that the in vivo action of the different factors in E-cadherin repression can be modulated by their relative concentrations as well as by specific cellular or tumour contexts.This work was supported by the Spanish Ministry of Science and Technology (SAF2001-2819), Instituto de Salud Carlos III (FIS01/1174) and the Comunidad Autónoma de Madrid (08.1/0055./2000). V.B. has been funded by predoctoral fellowships from the Fundación Científica de la Asociación Española contra el Cáncer (AECC) and Instituto de Salud Carlos III. H.P. is a predoctoral fellow of the Spanish Ministry of Education, Culture and Sports.Peer reviewe

Resistivity image beneath an area of active methane seeps in the west Svalbard continental slope

The Arctic continental margin contains large amounts of methane in the form of methane hydrates. The west Svalbard continental slope is an area where active methane seeps have been reported near the landward limit of the hydrate stability zone. The presence of bottom simulating reflectors (BSRs) on seismic reflection data in water depths greater than 600 m suggests the presence of free gas beneath gas hydrates in the area. Resistivity obtained from marine controlled source electromagnetic (CSEM) data provides a useful complement to seismic methods for detecting shallow hydrate and gas as they are more resistive than surrounding water saturated sediments. We acquired two CSEM lines in the west Svalbard continental slope, extending from the edge of the continental shelf (250 m water depth) to water depths of around 800 m. High resistivities (5–12 Ωm) observed above the BSR support the presence of gas hydrate in water depths greater than 600 m. High resistivities (3–4 Ωm) at 390–600 m water depth also suggest possible hydrate occurrence within the gas hydrate stability zone (GHSZ) of the continental slope. In addition, high resistivities (4–8 Ωm) landward of the GHSZ are coincident with high-amplitude reflectors and low velocities reported in seismic data that indicate the likely presence of free gas. Pore space saturation estimates using a connectivity equation suggest 20–50 per cent hydrate within the lower slope sediments and less than 12 per cent within the upper slope sediments. A free gas zone beneath the GHSZ (10–20 per cent gas saturation) is connected to the high free gas saturated (10–45 per cent) area at the edge of the continental shelf, where most of the seeps are observed. This evidence supports the presence of lateral free gas migration beneath the GHSZ towards the continental shelf

U B V R I Photometry of Stellar Structures throughout the Disk of the Barred Galaxy NGC 3367

We report new detailed surface U, B, V, R, and I photometry of 81 stellar structures in the disk of the barred galaxy NGC 3367. The images show many different structures indicating that star formation is going on in the most part of the disk. NGC 3367 is known to have a very high concentration of molecular gas distribution in the central regions of the galaxy and bipolar synchrotron emission from the nucleus with two lobes (at 6 kpc) forming a triple structure similar to a radio galaxy. We have determined the U, B, V, R, and I magnitudes and U - B, B - V, U - V, and V - I colors for the central region (nucleus), a region which includes supernovae 2003 AA, and 79 star associations throughout NGC 3367. Estimation of ages of star associations is very difficult due to several factors, among them: filling factor, metallicity, spatial distribution of each structure and the fact that we estimated the magnitudes with a circular aperture of 16 pixels in diameter, equivalent to $6''.8\sim1.4$ kpc. However, if the colors derived for NGC 3367 were similar to the colors expected of star clusters with theoretical evolutionary star tracks developed for the LMC and had a similar metallicity, NGC 3367 show 51 percent of the observed structures with age type SWB I (few tens of Myrs), with seven sources outside the bright surface brightness visible disk of NGC 3367.Comment: Accepted for publication (abr 2007) in The Astronomical Journal (July 2007 issue

Tercera revascularización miocárdica quirúrgica. Único paciente presentado en Cuba

A 49 years old male, white, smoker patient is presented. A severe coronary disease was demonstrated by means of coronariography. Surgical myocardial revascularization was necessarily performed in three opportunities.Se presenta un paciente de 49 años de edad, masculino, blanco, fumador. Se demostró por coronariografía la presencia de una enfermedad coronaria severa y se determinó necesario realizar revascularización miocárdica quirúrgica en tres oportunidades

Next generation of selenocyanate and diselenides with upgraded leishmanicidal activity

Nowadays, leishmaniasis is still treated with outdated drugs that present several obstacles related to their high toxicity, long duration, parenteral administration, high costs and drug resistance. Therefore, there is an urgent demand for safer and more effective novel drugs. Previous studies indicated that selenium compounds are promising derivatives for innovative therapy in leishmaniasis treatment. With this background, a new library of 20 selenocyanate and diselenide derivatives were designed based on structural features present in the leishmanicidal drug miltefosine. Compounds were initially screened against promastigotes of L. major and L. infantum and their cytotoxicity was evaluated in THP-1 cells. Compounds B8 and B9 were the most potent and less cytotoxic and were further screened for the intracellular back transformation assay. The results obtained revealed that B8 and B9 showed EC50 values of 7.7 µM and 5.7 µM, respectively, in L. major amastigotes, while they presented values of 6.0 µM and 7.4 µM, respectively, against L. infantum amastigotes. Furthermore, they exerted high selectivity (60 70) towards bone marrow-derived macrophages. Finally, these compounds exhibited higher TryR inhibitory activity than mepacrine (IC50 7.6 and 9.2 µM, respectively), and induced nitric oxide (NO) and reactive oxygen species (ROS) production in macrophages. These results suggest that the compounds B8 and B9 could not only exert a direct leishmanicidal activity against the parasite but also present an indirect action by activating the microbicidal arsenal of the macrophage. Overall, these new generation of diselenides could constitute promising leishmanicidal drug candidates for further studies

HeIse Wheels: a Family of Mechanisms for Implementing Variable Geometry Hybrid Wheels

This paper presents a family of mechanisms of two degrees of freedom for implementing variable geometry hybrid wheels. These mechanisms are capable of transforming a circular wheel into a hybrid wheel with multiple legs. In this paper we describe the main attributes and advantages of these mechanisms, which we named HeIse Wheels. In addition, various terms and concepts related to the mathematical modeling of these devices are defined. The family of mechanisms consists of 14 original designs, which represent a sound solution to the problem of wheel-hybrid wheel transformation

La esofagitis eosinofílica. ¿El Norte contra el Sur? Enfoque mecanicista bio-económico-social e implicaciones clínicas

La esofagitis eosinofílica (EEo) es una enfermedad crónica mediada por alérgenos, caracterizada por síntomas esofágicos, eosinofilia esofágica y ausencia de respuesta favorable a inhibidores de la bomba de protones (IBP). En los adultos es la causa más frecuente de disfagia e impactación alimentaria. Su incidencia y prevalencia son muy altas en los países desarrollados (EUA, Europa y Australia), en donde ha alcanzado una connotación de epidemia. Mientras que en los países desarrollados se publican estudios con grandes series de pacientes, en nuestro subcontinente se reporta en series con pocos casos o en casos aislados. Las causas de las diferencias de la prevalencia de la enfermedad entre ambas regiones se desconocen. Se han invocado causas genéticas o raciales. No obstante, el carácter epidémico de la enfermedad sugiere que las causas ambientales son más poderosas. Con base en hipótesis publicadas, así como en los estudios epidemiológicos, en la presente revisión se discutirán algunas de las posibles causas de la disparidad de prevalencia de la EEo entre ambos tipos de países. Se revisará la «hipótesis de la higiene», así como la posible relación del Helicobacter pylori, los parásitos intestinales y las modificaciones de la microbiota esofágica con la EEo. Con base en estudios realizados en EUA, se revisará el comportamiento clínico y evolutivo de la EEo en individuos hispanos y se discutirá acerca de un posible fenotipo predominante en los pacientes de América Latina y México. Finalmente, sobre la base anterior, se propondrá un algoritmo de estudio de la enfermedad en nuestros países. ABSTRAC Eosinophilic esophagitis is a chronic antigen-mediated disease characterized by esophageal symptoms, esophageal eosinophilia, and the absence of response to proton pump inhibitors. It is the most frequent cause of dysphagia and food impaction in adults. Its incidence and prevalence is very high in the developed countries (USA, Europe, Australia), where its connotation is that of an emerging epidemic. While studies have been published with large case series in the developed countries, those published in Latin America are small or consist of isolated case reports. The differences in the prevalence of the disease between the developed and developing regions are unknown. Genetic or racial causes have been cited. Nevertheless, the epidemic nature of the disease suggests that environmental causes are the most powerful. Based on the published hypotheses, as well as on epidemiologic studies, the present review discusses some of the possible causes of the disparity in the prevalence of eosinophilic esophagitis between the two types of countries. The ‘hygiene hypothesis’ is reviewed, together with the possible relation of Helicobacter pylori, intestinal parasites, and modifications of the esophageal microbiota in patients with eosinophilic esophagitis. In reference to studies conducted in the United States, the clinical behavior and progression of eosinophilic esophagitis in Hispanics is reviewed and a possible predominant phenotype in Mexican and other Latin American patients is discussed. Finally, based on the above, an algorithm for studying the disease in the Latin American countries is proposed

Possibilities to improve soil physical properties in garlic cultivation with cover crops as living mulches

[EN] The cultivation system with cover crops as living mulches is growing in importance in the worldwide agriculture as it combines an economical effect with pro-ecological and soil protecting activities. The plant species tested in the research were not frost resistant: buckwheat, millet, white mustard and berseem clover. A control were the plots without cover crops. The intercrops were sown in the first decade of August, in autumn a grown biomass was a living mulch, and after being damaged by frost in spring, the mulch was covering ground surface. Winter garlic bulbs were planted in grown biomass of cover plants, in the first decade of September. In the first decade of November and in the first decade of April, the selected soil parameters were determined in the soil layer of 0¿10 cm: actual soil moisture (%), soil bulk density (Mg · m¿3), total porosity (%) and water stability of soil aggregates (%). The harvest of garlic was conducted in the first decade of July. Cover crops mulches had an influence on soil physical properties. In spring, the soil from plots with cover crops mulching characterized with the highest moisture, higher total porosity and soil aggregates stability as well as lower soil bulk density. In comparison to the control cultivation of winter garlic, without cover crops, the effect of plants used for mulching on marketable yield was not observed. Garlic plants intercropped with the white mustard mulch formed leaves and bulbs of higher weight in comparison to cultivation without cover crops.Research was financed by the Ministry of Science and Higher Education of the Republic of Poland as part of the statutory activities of the Department of Vegetable Crops and Medicinal Plants, University of Life Sciences in Lublin.Salata, A.; Moreno-Ramón, H.; Ibañez Asensio, S.; Buczkowska, H.; Nurzynska-Wierdak, R.; Witorozec, A.; Parzymies, M. (2017). Possibilities to improve soil physical properties in garlic cultivation with cover crops as living mulches. Acta Scientiarum Polonorum Hortorum Cultus. 16(6):157-166. https://doi.org/10.24326/asphc.2017.6.14S15716616