284 research outputs found
D-mannose transport and metabolism in isolated enterocytes
D-mannose transport and metabolism has been studied in enterocytes isolated from chicken small intestine. In the presence of Na+, the mannose taken up by the cells either remains free, is phosphorylated, is catabolized to H2O, or becomes part of membrane components. The mannose remaining free in the cytosol is released when the cells are transferred to an ice bath. The Na+-dependent D-mannose transport is electrogenic and inhibited by ouabain and dinitrophenol; its substrate specificity differs from SGLT-1 transporter. The Glut2 transporter inhibitors phloretin and cytochalasin B added following 30-min mannose uptake reduced the previously accumulated D-mannose, whereas these two agents increased the cell to external medium 3-O-methyl-glucose (3-OMG) concentration ratio. D-mannose efflux rate from preloaded D-[2-3H]-mannose enterocytes is Na+-independent. Phloretin did not affect D-mannose efflux rate, whereas it inhibited that of 3-OMG. Neither mannose uptake nor efflux rate were affected by fructose. It is concluded that part of the mannose taken up by the enterocytes is rapidly metabolized and that enterocytes have two D-mannose transport systems: one is concentrative and Na+-dependent and the other is Na+-independent and passive.Dirección General de Investiagación Científica y Técnica PM99-012
Los costos ambientales del abastecimiento de agua a las ciudades. El caso de la zona metropolitana de Guadalajara
El presente artículo analiza la demanda, abastecimiento y saneamiento de agua de la zona metropolitana de Guadalajara (ZMG) en la segunda mitad del siglo próximo pasado, como consecuencia del desmedido crecimiento urbano-industrial, lo cual ha rebasado la capacidad de respuesta por parte de los municipios. Los autores ponen un especial énfasis en el análisis del proyecto propuesto por la Comisión Estatal de Agua y Saneamiento (CEAS) del estado de Jalisco para la solución del problema de abastecimiento de agua y su saneamiento a través de la construcción de una presa en el sitio de Arcediano, bajo la mirada del desarrollo sustentable.
Tratamiento del compromiso femoropatelar mediante la transposición de la tuberosidad tibial anterior según la técnica de Maquet II
Se presentan 50 rodillas en un total de 40 pacientes intervenidos entre los años
1983 y 1990 con la técnica de Maquet II por presentar compromiso femoropatelar. El objetivo de
este trabajo ha sido la valoración de la evolución de los resultados a lo largo del tiempo. La edad
media de los pacientes ha sido de 48 años, con un seguimiento medio de 8 años y 4 meses. La patología
femoropatelar se ha dividido en 2 grupos: artrosis y condromalacia avanzada. El injerto
óseo utilizado ha sido autólogo en el 30% de los casos y heterólogo de banco en los restantes, con
un adelantamiento medio de la tuberosidad tibial anterior (TTA) de 11 mm. La valoración de resultados
se realizó teniendo en cuenta parámetros clínicos y radiográficos, realizando una primera
valoración en junio de 1992 y otra en marzo de 1996. Los resultados globales han sido de
un 68% de resultados muy buenos y buenos, 22% regulares y 10% malos, apreciándose un escaso
deterioro de los mismos entre las 2 revisiones. Se concluye que la técnica es válida para este tipo
de patología, siendo suficiente el adelantamiento de la TTA de 10 mm.We present 50 knees in 40 patients who were operated between 1983 and 1990
with Maquet II procedure because of patellofemoral pathology. The purpose of this work was the
long-term evaluation of results. The average age of the patients was 48 years with a mean followup
of 8 years and 4 months. The patellofemoral pathology was divided in 2 groups: osteoarthrosis
and advanced chondromalacia. The bone graft employed was autologous graft in 30% cases and
heterologous graft in the others, with an average anterior displacement of the anterior tibial tuberosity
of 11 mm. The evaluation of the results was done based on clinical and radiographical parameters.
The final outcome was found to be 68% of very good and good results, 22% fair and 10%
bad results. An slight impairement was observed along the period of study. The conclusion is that
this procedure is valid for this pathology, being enough an anterior displacement of the tibial tuberosity
of 10 mm
The application of diode laser in the treatment of oral soft tissues lesions. A literature review
Since its appearance in the dental area, the laser has become a treatment of choice in the removal of lesions in the oral soft tissues, due to the numerous advantages they offer, being one of the most used currently the diode laser. The aim of this review was to determine the efficacy and predictability of diode laser as a treatment of soft tissue injuries compared to other surgical methods. A literature review of articles published in PubMed/MEDLINE, Scopus and the Cochrane Library databases between 2007 and 2017 was performed. ?Diode laser?, ?soft tissue?, ?oral cavity? and ?oral surgery? were employed for the search strategy. Only articles published English or Spanish were selected. The diode laser is a minimally invasive technology that offers great advantages, superior to those of the conventional scalpel, such as reduction of bleeding, inflammation and the lower probability of scars. Its effectiveness is comparable to that of other types of lasers, in addition to being an option of lower cost and greater ease of use. Its application in the soft tissues has been evaluated, being a safe and effective method for the excision of lesions like fibromas, epulis fissuratum and the accomplishment of frenectomies. The diode laser can be used with very good results for the removal of lesions in soft tissues, being used in small exophytic lesions due to their easy application, adequate coagulation, no need to suture and the slightest inflammation and pain
Na+-dependent D-mannose transport at the apical membrane of rat small intestine and kidney cortex
The presence of a Na+/D-mannose cotransport activity in brush-border membrane vesicles (BBMV), isolated from either rat small intestine or rat kidney cortex, is examined. In the presence of an electrochemical Na+ gradient, but not in its absence, D-mannose was transiently accumulated by the BBMV. D-Mannose uptake into the BBMV was energized by both the electrical membrane potential and the Na+ chemical gradient. D-Mannose transport vs. external D-mannose concentration can be described by an equation that represents a superposition of a saturable component and another component that cannot be saturated up to 50 μM D-mannose. D-Mannose uptake was inhibited by D-mannose ≫ D-glucose > phlorizin, whereas for α-methyl glucopyranoside the order was D-glucose = phlorizin ≫ D-mannose. The initial rate of D-mannose uptake increased as the extravesicular Na+ concentration increased, with a Hill coefficient of 1, suggesting that the Na+ :D-mannose cotransport stoichiometry is 1:1. It is concluded that both rat intestinal and renal apical membrane have a concentrative, saturable, electrogenic and Na+-dependent D-mannose transport mechanism, which is different from SGLT1.Dirección General de Investigaciones Científicas y Técnicas PM99-012
Implementing a Distance Estimator for a Wildlife Tracking System Based on 802.15.4
In this work, a novel distance estimation mechanism using received signal strength
indication (RSSI) signals with ZigBee modules is designed, implemented and tested in several
scenarios. This estimator was used for a research project focused on a wildlife behavioral classification
system deployed in Doñana’s National Park. As a supporting feature for that project, this work
was implemented for locating animal’s collars acting as wireless nodes in order to find those who
went outside of the coverage area of the network or that were accidentally detached from animals.
This work describes the system architecture and the implementation of a mobile assistant capable of
recovering devices located beyond the coverage of the network. The analytical model needed for
distance estimation and the signal filtering are described, as well as the difficulties that the researchers
must deal when building robust location estimators. This theoretical model was applied to three
different scenarios and tested with two validation experiments.Junta de Andalucía P12-TIC-130
Sampling Frequency Evaluation on Recurrent Neural Networks Architectures for IoT Real-time Fall Detection Devices
Falls are one of the most frequent causes of injuries in elderly people. Wearable Fall Detection Systems
provided a ubiquitous tool for monitoring and alert when these events happen. Recurrent Neural Networks
(RNN) are algorithms that demonstrates a great accuracy in some problems analyzing sequential inputs, such
as temporal signal values. However, their computational complexity are an obstacle for the implementation
in IoT devices. This work shows a performance analysis of a set of RNN architectures when trained with
data obtained using different sampling frequencies. These architectures were trained to detect both fall and
fall hazards by using accelerometers and were tested with 10-fold cross validation, using the F1-score metric.
The results obtained show that sampling with a frequency of 25Hz does not affect the effectiveness, based
on the F1-score, which implies a substantial increase in the performance in terms of computational cost. The
architectures with two RNN layers and without a first dense layer had slightly better results than the smallest
architectures. In future works, the best architectures obtained will be integrated in an IoT solution to determine
the effectiveness empirically.Ministerio de Economía y Competitividad TEC2016-77785-
Humoral Immune Response to Salmonella Antigens and Polymorphisms in Receptors for the Fc of IgG in Patients with Ankylosing Spondylitis
The Benzú rockshelter (Ceuta). Stratigraphic sequence and record of Hunter Gatherer societies of marine resource with Mode 3 technology in North Africa
Synthesis, antibacterial and antifungal activities of naphthoquinone derivatives: a structure–activity relationship study
The synthesis of 1,4-naphthoquinone derivatives is of great interest since these compounds exhibit strong activity as antimalarial, antibacterial, antifungal and anticancer agents. A series of 50 naphthoquinone derivatives was synthesized and evaluated for antibacterial and antifungal activity against Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Candida krusei, Candida parapsilosis and Cryptococcus neoformans using the broth microdilution method. The Candida species were the most susceptible microorganisms. Halogen derivatives of 1,4-naphthoquinone presented strong activity, e.g., 2-bromo-5-hydroxy-1,4-naphthoquinone, which exhibited inhibition at an MIC of 16 lg/ mL in S. aureus, and 2-chloro-5,8-dihydroxy-1,4-naphthoquinone, with an MIC of 2 lg/mL in C. krusei. These compounds showed higher activity against fungi, but the antibacterial activities were very low. The study of structure–activity relationships is very important in the search for new antimicrobial drugs due to the limited therapeutic arsenal
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