Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Myofascial pain syndrome (MPS) causes pain and limitations, being quite prevalent in the population. The diagnosis is due to the clinical presentation and physical examination, being the local pain the main symptom, which counts with a characteristic irradiation according to the affected muscle. Due to this irradiation, the condition may mimic other common clinical situations and should be remembered as a differential diagnosis. Its identification and treatment can be done in a simple way and the primary care professional is able to perform them, however, it is still neglected, being a poorly studied condition. Treatment includes drugs, lifestyle changes, physiotherapy and needling techniques, which can be dry or injected. Needling with anesthetic infiltration seems to be an effective technique in the deactivation of muscle trigger points and seems to be superior to others in some studies, with the advantage of being less painful in its accomplishment. The objective of this study is to perform a literature review on MPS, taking into account the clinical presentation, diagnosis and treatment, portraying results with several needling techniques and comparing them with each other and with other techniques.

The haemoglobin A1c (HbA1c) test is the gold standard in monitoring diabetes mellitus. HbA1c can be falsely decreased or increased in some particular scenarios, as in hemoglobinopathies, inadequately reporting the glycemic control. Here we present the case of a patient with a HbA1c value incompatible with self-monitoring blood glucose levels, due to the presence of hemoglobin N-Baltimore. This case is relevant because, in spite of being asymptomatic, the presence of this type of hemoglobin leads to an incorrect appearance of glycemic control, if standard methods for HbA1c determination are used.

Background: Plant-origin meals have been proposed as an alternative to fishmeal as a source of protein in diets for rainbow trout (Oncorhynchus mykiss) and one suggested alternative is corn gluten. Goals: Determine the effects on the growth and other physiological parameters of rainbow trout juveniles fed diets made with corn gluten as substitute for fishmeal. Methods: Three diets that substituted corn gluten in ratios of 50, 75, and 100% (G50%, G75% and G100%, respectively) for fishmeal were fed during 90 days to juveniles initially weighing14.7 ± 0.2 g (mean ± standard error). We measured growth performance, oxygen consumption, P and N excretion, protein and lipid contents in muscle and liver, as well the number of lymphocytes and burst activity of the kidney macrophage. Results: Growth performance (weight gain and specific growth rate) decreased as corn gluten increased in the diet. The organisms fed with G75% and G100% diets had a significantly lower de­position of protein in the muscle with respect to the other groups, while lipid deposition increased in the same tissue. Increasing levels of the corn gluten in the diet caused increased oxygen consumption and N ammonium excretion but did not affect the number of lymphocyte and the macrophage activity. Conclusions: Corn gluten may be used at a substitution level up to 50% in diets for juvenile rainbow trout.

The structure of benthic diatom assemblages (diversity, equitability, dominance) may be useful in assessing their ecological status in natural protected areas. Goals. To describe the structure of epipelic diatom assemblages from Laguna Guerrero Negro (LGN), a protected coastal lagoon, and test the hypothesis that H´diversity values would be higher for diatom assemblages in LGN sediments than in typical benthic diatom assemblages. Methods. Sediment samples were collected in the lagoon on November 2013, and January, March, and July 2014. Diatoms were mounted on permanent slides and examined at 1000× using phase contrast microscopy. In each slide, 500 valves were counted to compute relative abundances of each taxon, and species diversity, equitability, and dominance, using Shannon (H´), Pielou (J´), and Simpson (?) indices, respectively. Likewise, similarity between samples was measured. The calculated median value of H´ from LGN was compared to previously recorded median values to test the hypothesis that significant differences exist. Results. A total 225 diatom taxa were counted. With few exceptions, the similarity between samples was <60%. Relative abundances depict typical benthic diatom assemblages, with an average H´= 4.96 bits/taxon, and corresponding values of equitability and dominance. The median value of H´ (Md = 4.9) was significantly higher than the median value (Md = 3.7) found in previous studies. Conclusions. The structure of the epipelic diatom assemblages from LGN and their patchy distribution are similar to that of typical diatom assemblages, but with unusually high values of H´ that lead us to reject the statistical null hypothesis and thus sustain our research hypothesis.

Background: The species red-rimmed melania Melanoides tuberculata Müller, 1774 is native to Asia and Africa. Due to the aquarium trade, its worldwide distribution has widely increased. In Mexico, its presence in the wild has been documented since 1973 in different Mexican states. Goals: Document the first record of the presence of the species in the state of San Luis Potosí. Methods: During 2015 - 2018, different perennial water bodies were sampled in San Luis Potosí, and the presence or absence of the species was recorded. Photographic images of the exotic snail were taken for taxonomic identification and specimens collected in the study were deposited at the Colección Nacional de Moluscos – Instituto de Biología (UNAM). Results: On June 16, 2017, some individuals were found in an area near the town of San Francisco de Asís, municipality of Rioverde. Conclusions: This study contributes to the knowledge of the dispersal of the exotic red-rimmed melania in Mexico and is the first record of its presence in the state of San Luis Potosí. We consider that the current incidence of the exotic snail in the state is low. Because of its high dispersion potential, however, it could be a risk for native aquatic fauna, considering its role as an intermediate host of parasitic diseases of wild bird and fish species.

Background. One of the most severe problems in coastal systems is eutrophication. It is a process of anthropic origin Tha t mainly increases the concentrations of nitrogen, organic matter, and/or phosphorus in bodies of water. The trophic index  most  used  in  Mexico  to  determine  the  state  of  coastal  or  marine  systems  is  the  TRIX  index.  Goals. To evaluate the trophic state of the Pom-Atasta (PA) and Palizada del Este fluvial-lagoon systems through the TRIX index. Methods. During different months from 2005 to 2014, water samples were collected at ten sampling sites for each fluvial-lagoon system to evaluate a number of physical variables (dissolved oxygen), chemicals (nitrogenous components and reactive phosphorus), and chlorophyll a , both on the surface andeat middle depths. The TRIX index was used to analyze the trophic state  of  the  systems. Results. The  PA  and  PE  systems  were  characterized  as  oligotrophic  systems  with  mesotrophic tendency. Conclusions.  We recommend that the water quality and the magnitude of cholorophyll  A  at the Pom-Atasta and Palilzadadel Este systems continue to be monitoredain order to establish seasonal or annual trends of the trophic state of these systems.

Background. The Crocodylia begin their life by overcoming the incubation stage with group hatching. Incubation temperature is important for the development of the embryos and the duration of the hatching process, during which they emit sounds. Goals. The effect of the size of the clutch on the duration and success of hatching is reported for the first time, and the hatching process is described. Methods. We used four clutches supplied by the "Granja de Lagartos" farm in Tabasco, Mexico, from the 2010 breeding season, and each was distributed in containers to integrate three clutches of different size: large (15 eggs), medium (nine eggs), and small (one egg). We monitored the temperature, relative humidity, and the number of eggs hatched in each clutch. The duration of hatching and the incubation period were statistically compared, as well as hatching success among the three brood sizes. We made sure that incubation conditions were the same for all boxes. Results. The small clutches (? = 3340, ± 2794 min) and the medium-sized ones (? = 1844 ± 476 min) took less minutes to hatch, and both took less time than the large clutches (? = 9431 ± 768 min). The hatchings began with the vocalization of pre-hatching calls, heard up to a week before eclosion. Conclusions. The size of the clutch influences the duration of hatching, but is not related to hatching success.  

El mapeo del fondo marino genera información útil para estudios ecológicos y de conservación en zonas marinas. Sin embargo, las metodologías para la delimitación de unidades en los fondos dominados por sedimentos no consolidados son escasas. Objetivos. Clasificar y caracterizar unidades en el fondo marino a partir de la distribución espacial de cuatro variables: el contenido de carbonato de calcio, el tamaño medio de grano, la clasificación del sedimento y la profundidad en la bahía de La Paz. Métodos. La distribución espacial de las cuatro variables mencionadas fue generada a partir de modelos de interpolación. Los modelos se elaboraron con base en los datos de 85 muestras de sedimento superficial y utilizando un sistema de información geográfica. La clasificación de unidades se determinó agrupando polígonos construidos a partir de los modelos e implementando un análisis de agrupamiento jerárquico. La caracterización se obtuvo con los valores predichos en los modelos. Resultados. Los modelos presentaron valores entre 2.7 a 95% de contenido de carbonato de calcio, -0.9 a 7.8 ? de tamaño medio de grano (donde ? es una transformación logarítmica del diámetro de sedimento), 0.1 a 4 ? de clasificación y 0 a 680 m de profundidad. El análisis jerárquico determinó 14 unidades en el fondo marino. Cuatro unidades conforman el 91% del área de estudio. La unidad 4a se caracteriza por un alto contenido de CaCO3 (72 ± 20%); la unidad 3a, por una mala clasificación (2.2 ± 0.7 ?); la unidad 2a, por una clasificación moderada (1.1 ± 0.3 ?), y la unidad 1a, por la presencia de sedimentos finos (4.5 ± 0.6 ?). Conclusiones. Este estudio representa una de las primeras propuestas de clasificación de unidades del fondo marino sobre sedimentos no consolidados en la BLP. La metodología empleada permitió separar cuatro principales unidades que reflejan condiciones ambientales con características propias. También se establecen los primeros modelos de distribución por medio del cálculo de la media del error y la raíz cuadrada del error cuadrático medio, que contrasta un conjunto de observaciones independientes contra los valores modelados de las variables citadas. Esta propuesta se puede utilizar como línea base en estudios de zonas costeras y plataformas continentales del Golfo de California y otras regiones marinas, en tanto dicha distribución no se vea afectada por eventos hidrometeorológicos extremos, en cuyo caso se requeriría un estudio similar.

El aprovechamiento comercial de Macrobrachium tenellum en el río San Pedro Mezquital, Nayarit, inició en 1995 como una pesquería temporal que cubría la demanda local. Posteriormente, la pesquería se intensificó como actividad económica alterna, y logró un impacto regional mediante la producción de alimento y la generación de empleos. Objetivos. Estimar los parámetros de crecimiento y mortalidad de M. tenellum en el río San Pedro Mezquital, Nayarit. Métodos. Los muestreos se realizaron de febrero a octubre de 2010. Para la captura se utilizaron atarrayas de 1.0 y 1.5 pulgadas de luz de malla y un tamaño de muestra de 100 individuos. Los grupos de edad se obtuvieron por el método de Cassie, los parámetros de crecimiento con el método de Walford, la mortalidad total anual por el método de Beverton y Holt y la mortalidad natural con la ecuación de Rikhter y Effanov. Resultados. Las hembras mostraron valores de L? = 19.0 cm, P? = 55 g, k = 0.369 mes-1 y t0 = -0.035 mes-1; en el caso de los machos, fueron L? = 26.6 cm, P? = 239 g, k = 0.221 mes-1 y t0 = -0.042 mes-1. Con base en la relación longitud-peso, las hembras presentaron crecimiento alométrico negativo (b < 3) y los machos crecimiento alométrico positivo (b > 3). Los parámetros de mortalidad fueron para las hembras Z = 3.84 año-1, M = 0.72 año-1 y E = 0.79 año-1 y para los machos Z = 2.75 año-1, M = 0.69 año-1 y E = 0.70 año-1. Conclusiones. El langostino Macrobrachium tenellum presenta un ciclo de vida corto menor de dos años, una tasa de crecimiento moderada y tasas de mortalidad total y de explotación altas, lo que ocasiona una sobreexplotación del recurso en el área de estudio.

Debido a que no existen estudios sobre el lixiviación de nutrientes de las heces de camarón Litopenaeus vannamei, se diseñó el presente estudio. Objetivos. Estimar la pérdida de nutrientes de las heces del camarón blanco del Pacífico (Litopenaeus vannamei). Métodos. Se utilizaron 15 juveniles de 4.9 ± 1.0 g de peso por cada uno de cuatro acuarios replicados por tratamiento. En un ensayo de alimentación con una dieta de referencia comercial, la cual fue reprocesada para añadir 1% de óxido de cromo como marcador inerte y 1% de alginato de sodio (aglutinante). El tratamiento 1(T1) consistió en que las heces permanecieron en agua marina durante 3 horas después de su colecta, mientras en el tratamiento 2 (T2), las heces fueron colectadas y congeladas inmediatamente después de su emisión. Además existió alternancia de los tratamientos en las réplicas. Resultados. El contenido de materia seca (MS), proteína cruda (PC) y aminoácidos totales en heces fue muy similar para los dos tratamientos. El mismo efecto se presentó para los coeficientes de digestibilidad aparente de MS, PC y aminoácidos. Conclusiones. Con base en lo anterior podemos inferir que la lixiviación de nutrientes (MS, PC y AA) de las heces de camarones no se ve afectada por efecto del tiempo de colecta en un lapso igual o menor a 3 horas después de su emisión y por lo tanto, no es necesario ajustar los coeficientes de digestibilidad aparente de materia seca, proteína cruda y aminoácidos.