Abstract Background Infraclavicular brachial plexus nerve block is a commonly performed anesthesiology technique in the upper extremity. Local anesthetics may be administered at different temperatures for both neuraxial and peripheral nerve blocks. We aimed to evaluate the effects of the temperature of the local anesthetic at the time of administration on the onset and duration of sensory and motor blocks in infraclavicular brachial plexus nerve block. Methods A total of 80 patients undergoing elective upper extremity surgery were randomly assigned to one of the following groups using a computer-based randomization software; low temperature (4 °C) (Group L, n = 26), room temperature (25 °C) (Group R, n = 27) and warmed (37 °C) (Group W, n = 27). A 1:1 mixture of 2% lidocaine and 0.5% bupivacaine was used as local anesthetic. Infraclavicular brachial plexus nerve block was performed under ultrasound guidance in all patients preoperatively. The onset and duration of sensory and motor blocks were recorded. Results Each group had different onset of motor (p< 0.001) and sensory (p< 0.001) blocks. The duration of motor block was similar between groups (p= 221). However, a significant difference was found in the duration of sensory block between group L (399.1 ± 40.8 min) and group R (379.6 ± 27.6 min) (p= 0.043). There was no complication related to nerve block procedure. Conclusions The administration of the local anesthetic at lower temperatures may prolong the onset of both motor and sensory blocks in infraclavicular brachial plexus nerve block.

Mesenchymal stem cells are highly proliferative and have the potential to differentiate into several cell lineages. These qualities make them an ideal biological model in the study and development of biotechnological tools for use in veterinary medicine and animal production. This paper reviews the information available on mesenchymal stem cells in domestic species and their possible uses, present and future, for veterinary medicine and animal production: engineering and tissue regeneration, treatment of chronic diseases, generation of animals with better production characteristics, assisted reproduction of genetically superior animals or of endangered species and better understanding of the processes of tissue development and metabolism of domestic species.

Las células troncales mesenquimales poseen capacidad proliferativa alta y potencial de diferenciarse a diversos linajes celulares. Estas cualidades las hacen un modelo biológico idóneo en el estudio y desarrollo de herramientas biotecnológicas para su uso en la medicina veterinaria y en la zootecnia. En este artículo se analiza la información disponible sobre las células troncales mesenquimales de especies domésticas y se discuten posibles usos actuales y futuros en la medicina veterinaria y la zootecnia en ingeniería y regeneración de tejidos, tratamiento de enfermedades crónicas, generación de animales con mejores características productivas, reproducción asistida de animales genéticamente superiores o en peligro de extinción y mejor entendimiento de los procesos de desarrollo y metabolismo tisular de las especies domésticas.

Mesenchymal stem cells have characteristics that make them a unique model for research in the biomedical area. Its use as a biotechnological tool allows for innovative solutions for health problems in humans and animals. These cells are characterized by a high proliferative capacity of being viable for long periods and for their multipotent capacity to differentiate into a wide variety of cell lineages, having in it their value for tissue engineering and repair, treatment of diseases and manipulation of cell differentiation and even animal production. This paper covers basic aspects of their biology and characterization in domestic species emphasizing the need to homogenize the criteria that would allow to characterize these cells in the livestock species and their possible applications in health and livestock production.

Las células troncales mesenquimales poseen características que las convierten en un modelo único para la investigación en el área biomédica. Su empleo como herramienta biotecnológica permite soluciones innovadoras a problemas de salud en humanos y animales. Estas células se caracterizan por una alta capacidad proliferativa siendo viables por periodos prolongados y por su multipotencialidad al diferenciarse a diversos linajes celulares, radicando en ello su valor para la ingeniería y reparación de tejidos, tratamiento de enfermedades y manipulación de la diferenciación celular, e incluso la producción animal. El presente ensayo abarca aspectos básicos de su biología y caracterización en las especies domésticas, enfatizando la necesidad de homogenizar los criterios que permitirían caracterizar estas células en las especies pecuarias y sus posibles aplicaciones en salud y producción pecuaria.

On 16 November 2006, a female juvenile megamouth shark, Megachasma pelagios, was caught off the coast of Mexico in the Pacific Ocean, near Sebastián Vizcaíno Bay. This specimen, that has informally been referred to as "Megamouth No. 38", measured 2265 mm in total length. It represents the third smallest female recorded for this taxon and the first report of M. pelagios off the Pacific coast of Mexico. The specimen is formally described here with basic anatomical data, and some aspects of this megamouth shark are compared with those of previously reported M. pelagios specimens. The occurrence near Sebastián Vizcaíno Bay is significant because it further emphasizes the high elasmobranch diversity in the area that should be regarded as a key region for shark conservation.

El 16 de noviembre de 2006, una hembra juvenil del tiburón bocudo, Megachasma pelagios, fue capturada en la costa del Pacífico de México, cerca de la bahía Sebastián Vizcaíno. Este espécimen, informalmente conocido como "Megamouth No. 38", midió 2265 mm de longitud total. Representa la tercera hembra más pequeña registrada para este taxón y el primer registro de M. pelagios en la costa del Pacífico de México. El espécimen se describe formalmente a partir de sus datos anatómicos básicos, los cuales se comparan con aquellos provenientes de otros M. pelagios previamente documentados. Su presencia cerca de la bahía Sebastián Vizcaíno es importante porque destaca la presencia de una elevada diversidad de elasmobranquios en el área, que debería ser considerada como una región clave para la conservación de los tiburones.

Abstract A partial vertebral series of a lamniform shark (Chondrichthyes: Elasmobranchii) occurred in the “Vallecillo fish Member” of the Agua Nueva Formation (Upper Cretaceous: Lower Turonian) at Vallecillo, Mexico. Its taxonomic assignment below the ordinal level is tenuous, but the vertebrae closely resemble those of cretoxyrhinid sharks.This report represents the first documentation of a Cretaceous lamniform shark in northeastern Mexico. The shark could have measured slightly over 3 m in total body length. Because the vertebrae are articulated and are three-dimensionally preserved, they are thought to be deposited rather quickly on a soft oceanfloor after decomposition of most of the shark carcass.

Resumen Una serie de vértebras de la columna vertebral de un tiburón lamniforme (Chondrychthyes: Elasmobrachii) son reportadas en el “Miembro Vallecillo” de la Formación Agua Nueva (Cretácico Superior: Turoniano Inferior), en Vallecillo, México. Aunque su determinación taxonómica no fue realizada a nivel inferior al de Orden, las vértebras semejan aquellas pertenecientes a tiburones cretoxyrhinidos. Este reporte representa la primera documentación en México de un tiburón lamniforme del Cretácico. Este tiburón pudo haber tenido una longitud corporal ligeramente mayor a los 3 m. Debido a que las vértebras están articuladas y preservadas en tres dimensiones, éstas debieron ser depositadas relativamente rápido en un sedimento suave a fluido después de la descomposición de las partes blandas del tiburón.

In this work, the use of interval arithmetic is considered to increase robustness of geometric classification algorithms in B-Rep solid modeling systems. The classification algorithms, also known as incidence tests, are important to keep the consistency between topology and geometry in a solid model during the application of Boolean operations. An error in the incidence test has deep impact over the steps that follow the Boolean operations and can damage the result, generating an inconsistent solid. The interval arithmetic incorporates approximation errors, so that, it eliminates the need of defining a fixed tolerance to do the comparison between floating-point numbers. However, it is not possible to directly convert floating-point algorithms to interval arithmetic, so that, it is necessary to reformulate the entire algorithm. Another important step in the Boolean operation is the determination of intersection points where the use of interval arithmetic can have side effects as intervals with large dimensions, and may cause incidence tests failures. It is necessary to control the growth of the intervals based on the geometry and topology. This work will introduce the application of interval arithmetic to a B-Rep solid modeler.

O uso de estruturas artificiais como abrigos por peixes, foi avaliado objetivando o incremento da abundância de peixes na baía da Ilha Grande na costa da região sudeste brasileira. Cinco diferentes tipos de estruturas, feitas de telhas de barro, de crescentes tamanhos e complexidades foram testadas para avaliar sua eficiência como abrigos de peixes. Os peixes associados a cada tipo de estrutura foram contados, semanalmente de maio/1996 a abril/1997, através de observações subaquáticas realizadas por mergulho livre. De acordo com os padrões de abundância, dois grupos de peixes foram identificados. O primeiro formado por E. guaza, Chylomicterus sp, Sphoeroides sp M. rubra, R. randalli, S. hispidus, e Haemulun sp apresentou afinidade por fundos duros de relevo irregular cuja abundância proporcional ao tamanho e complexidade das estruturas, e o outro formado por S. Flaviventris, Scorpaena sp, Diapterus sp, Gerres spp, Anchoa sp, Oligoplites sp, e D. radiale que não apresentou ocorrência associada com as estruturas.

The use of artificial structures as a shelter for fishes was evaluated aiming to assess increase in fish abundance in Ilha Grande Bay at Southeast Brazilian coast (Lat: 22°8'-23°5' S; Long. 44º05’-44º40’W). Five different types of structures, made of clay tiles, with an increase range on size and complexity were tested to assess their efficiency. Fish were counted in each type of structure from May-1996 to April-1997 by underwater observation made with snorkelling. According to the pattern of concentration in the structures, two groups of fishes were identified. One comprised by E. guaza, M. rubra, R. randalli, S. hispidus, Sphoeroides sp and Haemulun sp showed affinity for hard bottom, irregular profile and an increase in abundance on the more complex and biggest structures. The other comprised by Chylomicterus sp, Gerres spp, Anchoa sp, Diapterus sp, Oligoplites sp and D. radiale did not present clear preference for hard bottom.

Insulin and glucagon are the hormonal polypeptides secreted by the B and A cells of the endocrine pancreas, respectively. Their major physiologic effects are regulation of carbohydrate metabolism, but they have opposite effects. Insulin and glucagon have various physiologic roles, in addition to the regulation of carbohydrate metabolism. The physiologic effects of insulin and glucagon on the cell are initiated by the binding of each hormone to receptors on the target cells. Morphologic studies may be useful for relating biochemical, physiologic, and pharmacologic information on the receptors to an anatomic background. Receptor radioautography techniques using radioligands to label specific insulin and glucagon receptors have been successfully applied to many tissues and organs. In this review, current knowledge of the histologic distribution of insulin and glucagon receptors is presented with a brief description of receptor radioautography techniques