Amphioxus makes the cut Again

The cephalochordate amphioxus is now established as an important model system for understanding the evolution of vertebrate novelties from an invertebrate chordate ancestor. It is also emerging as a serious candidate for studies of organ regeneration. We extend here our previous observations on the European amphioxus´ extensive adult regenerative capacity. The expression of Wnt5 and the presence of β-catenin protein in the early bud-stage blastema support a role for Wnt signaling during tail regeneration in amphioxus. We also present data showing that Branchiostoma lanceolatum continues to regenerate well after repeated amputation of the post-anal tail. These results are discussed in relation to vertebrate regeneration and other stem cell systems, and in the context of regeneration decline with aging

Geometrically induced modification of surface plasmons in the optical and telecom regimes

We demonstrate that the introduction of a subwavelength periodic modulation into a metallic structure strongly modifies the guiding characteristics of the surface plasmon modes supported by the system. Moreover, it is also shown how a new type of a tightly confined surface plasmon polariton mode can be created by just milling a periodic corrugation into a metallic ridge placed on top of a metal surface

JNK mediates differentiation, cell polarity and apoptosis during amphioxus development by regulating actin cytoskeleton dynamics and ERK signalling

c-Jun terminal kinase (JNK) is a multi-functional protein involved in a diverse array of context-dependent processes, including apoptosis, cell cycle regulation, adhesion and differentiation. It is integral to a number of signalling cascades, notably downstream of non-canonical Wnt and MAPK signalling pathways. As such, it is a key regulator of cellular behaviour and patterning during embryonic development across the animal kingdom. The cephalochordate amphioxus is an invertebrate chordate model system straddling the invertebrate to vertebrate transition and is thus ideally suited for comparative studies of morphogenesis. However, next to nothing is known about JNK signalling or cellular processes in this lineage. Pharmacological inhibition of JNK signalling using SP600125 during embryonic development arrests gastrula invagination and causes convergence extension-like defects in axial elongation, particularly of the notochord. Pharynx formation and anterior oral mesoderm derivatives like the preoral pit are also affected. This is accompanied by tissue-specific transcriptional changes, including reduced expression of six3/6 and wnt2 in the notochord, and ectopic wnt11 in neurulating embryos treated at late gastrula stages. Cellular delamination results in accumulation of cells in the gut cavity and a dorsal fin-like protrusion, followed by secondary Caspase3-mediated apoptosis of polarity-deficient cells, a phenotype only partly rescued by co-culture with the pan-caspase inhibitor Z-VAD-fmk. Ectopic activation of ERK signalling in the neighbours of extruded notochord and neural cells, possibly due to altered adhesive and tensile properties

Búsqueda de dianas en Podosphaera Xanthii para el desarrollo de nuevas fitoterapias antifúngicas

La resistencia a fungicidas en uno de los principales problemas de la agricultura y esto es especialmente patente en el caso de los oídios. En España y en las principales áreas productoras del mundo, el oídio de las cucurbitáceas es una amenaza muy grave, y Podosphaera xanthii es considerado como el principal agente causante de la enfermedad. Hasta la fecha, la aplicación de fungicidas y el uso de variedades resistentes son las principales herramientas para el control de la enfermedad. En cualquier caso, el oídio sigue imponiendo serias limitaciones en la producción agrícola, siendo necesario el desarrollo de nuevas estrategias de control. En este estudio se pretende proporcionar información sobre las bases moleculares de P. xanthii que pueda ser de utilidad para el desarrollo de nuevas herramientas de fitoprotección. Para lograr este objetivo, estamos centrando nuestra atención en un conjunto de proteínas fúngicas carentes de función, determinado en un estudio anterior. Ante la falta de homología con proteínas funcionalmente anotadas, para conocer la posible función de dichas proteínas, en primer lugar, llevamos a cabo un análisis in silico detallado de las proteínas que incluye modelado 3D, predicción de posibles ligandos e identificación de dominios funcionales. En segundo lugar, para la identificación de proteínas clave para la patogénesis de P. xanthii, silenciamos proteínas del hongo con función predicha bioinformáticamente mediante silenciamiento génico inducido por hospedador (HIGS) empleando Agrobacterium tumefaciens como vector para la expresión transitoria de construcciones de silenciamiento en células de melón, y desde ellas, al hongo diana. Finalmente, las proteínas con un fenotipo claro de silenciamiento serán seleccionadas para la caracterización de su actividad biológica. En este congreso se mostrarán los resultados más relevantes obtenidos hasta la fecha, relativos a la asimilación de azufre.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Este trabajo ha sido financiado por una ayuda del Programa Estatal de I+D+i Orientada a los Retos de la Sociedad (AGL2016-76216-C2-1-R), cofinanciada con fondos FEDER (UE). Los autores agredecen además ayudas del Plan Propio de Investigación de la Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Reflectometer comparison for assessment of back-silvered glass solar mirrors

This paper compares the two most common reflectometers used to assess the specular reflectance of back-silvered glass mirrors for Concentrating Solar Power (CSP) applications, namely the Device and Services (D&S) 15R-USB and the Abengoa Condor SR-6.1 instruments. Comparisons are first made between the two instruments themselves using a Gage Repeatability and Reproducibility (R&R) study. Results are given for the as-cleaned collector mirrors and then as the mirrors become naturally soiled over a one month period. The results of the Gage R&R study show that for the D&S the gage itself contributes 40.97% of the variability, whilst 59.03% is due to part-to-part (location on the mirror under investigation) variability. For the Condor we show that the % Contribution from the gage is 62.18% of the total variability with only 37.82% of the contribution attributable to the location dependent reflectance. The Condor has a wider acceptance angle, and over the reflectance range of 0.91–0.95 the condor was found to measure higher than the D&S by an average of 1.53%. The differences between the soiling results obtained from the two instruments are explained, and the results are used to derive a predictive model for the soiling of solar collectors. In conclusion, both instruments have advantages and shortcomings, and the factors that influence which instrument to select are discussed

Luxación tibio astragalina posteromedial sin fractura de maleolos: a propósito de un caso

Se describe un caso de luxación tibioastragalina posteromedial abierta sin fractura asociada de maleolos, en un paciente de 28 años. A los dos años del desbridamiento quirúrgico, reducción manual y reparación capsuloligamentosa, el paciente estaba libre de dolor y presentaba una función semejante a la del tobillo contralateral. Se revisa la literatura sobre el tema y se discuten los factores etiopatológicos, complicaciones y principios de tratamiento

Fracturas de cadera y diáfisis femoral ipsilaterales

Se aportan 10 casos de fracturas de cadera y diáfisis femoral ipsilaterales tratados quirúrgicamente de forma diferida con un tiempo medio de demora de 12 días (rango: 3 a 22 días). Nueve fracturas diafisarias fueron tratadas con placa AO de fémur, y una, donde la fractura de cadera asociada pasó inicialmente inadvertida, mediante un clavo de Küntscher. Las fracturas de cadera se fijaron con tornillos de esponjosa (8 casos) o clavo-placa de Richards (2 casos). En todos los pacientes se inició un programa de rehabilitación precoz. El seguimiento medio ha sido de 31 meses (rango: 12 a 84 meses). Todas las fracturas consolidaron. Las complicaciones fueron un caso de acortamiento femoral y otro de artrosis coxofemoral post-traumá- tica. En nuestra experiencia, la fijación de la fractura diafisaria con placa AO, combinada con tornillos de esponjosa o clavo-placa de Richards para la síntesis de la fractura de cadera, proporciona resultados satisfactoriosWe review 10 cases of ipsilateral hip and femoral shaft fractures. Operative treatment was performed in all cases, with an average delay of 12 days (range: 3 to 22 days). Nine femoral shaft fractures were stabilizated with an AO plate, and one, where the associated hip fracture was initially missed, with a Küntscher rod. Hip fractures were fixed with cancellous screws (8 cases) or Richards compression screw (2 cases). An early rehabilitation program was carried out in all patients. The average follow-up was 31 months (range: 12 to 84 months). All fractures healed. Complications were a case of femoral shortening an a case of post-traumatic hip osteoarthritis. In our study, the combination of AO plate for the shaft fracture with cancellous screws or Richards compression screw for the hip fracture provides good results

Lesiones traumáticas de la columna vertebral en niños

—Se ha realizado un estudio retrospectivo de los casos de traumatismo raquídeo atendidos en urgencias de nuestro centro desde 1987 hasta 1995. Del total de 159.202 niños atendidos en dicho período, el 1,8% sufría algún tipo de patología traumática de la columna, de los cuales requirieron ingreso 45 casos. Se analizan la distribución por edad, los factores etiológicos y la localización de la lesión. En 4 casos existió afectación neurológica, 2 de ellos con paraplejía completa. Los traumatismos del raquis en el niño son lesiones poco frecuentes, siendo aún más rara la afectación neurológica. fin nuestra serie el grupo más afectado fueron varones de 8 a 13 años de edad. El tratamiento conservador generalmente da resultados satisfactorios, recurriendo a la cirugía sólo en casos de severa inestabilidad o compromiso neurológico.We report the results of a restrospective study of cases with spinal trauma in children treated in our institution from 1987 until 1995. From 159,202 children under fourteen, only in 1.8% spinal traumatism was present being necessary hospitalization in 45 cases. We analized age distribution, etiologic factors, and level of the lesion. In four patients a neurologic deficit was present, two of them had complete paraplegia. Pediatric spinal trauma is a rare lesion, and associated neurologic deficit is still less common. In our scries, the most affected group was boys, from 8 to 13. Usually conservative treatment provides satisfactory results. Surgery is required only when severe unstability or neurologic deficit are present

Initial pH as a determining factor of glucose consumption and lactic and acetic acid production in oral streptococci

Lactic and acetic acid production was evaluated from six strains of oral streptococci, viz Streptococcus gordonii, Streptococcus mutans, Streptococcus oralis, Streptococcus salivarius, Streptococcus sanguis and Streptococcus sobrinus cultured in the presence of 1, 5, 10 mM glucose and without glucose, at initial pH values of 5, 5.5, 6 and 7. S. sobrinus and S. salivarius caused the greatest decreases in pH. At pH values of 5 and 5.5, lactic acid and acetic acid production in the species tested was discordant with residual glucose levels. Acid production from protein was especially great in S. mutans and S. salivarius

Spindle cell carcinoma: Two instances mistaken for vocal polyps

Spindle cell carcinoma is a variant of squamous carcinoma, with behavior that is apparently more aggressive than that of squamous carcinoma and that can produce distant lymphatic metastasis. It was first described by Virchow in 1864 [1], but the origin of the tumor is still not clear. The tumor is biphasic, with an epidermal component and a sarcomatous component involving spindle cells; transition zones between these components can be found [2–5]. In part due to this peculiar and complex nature, the tumor has accumulated various names since it was first described: sarcomatoid tumor, carci- nosarcoma, pleomorphic carcinoma, collision tumor, etc. [2,5,6]