3,638 research outputs found
Discrimination of milks with a multisensor system based on layer-by-layer films
Producción CientíficaA nanostructured electrochemical bi-sensor system for the analysis of milks has been developed using the layer-by-layer technique. The non-enzymatic sensor [CHI+IL/CuPcS]2, is a layered material containing a negative film of the anionic sulfonated copper phthalocyanine (CuPcS) acting as electrocatalytic material, and a cationic layer containing a mixture of an ionic liquid (IL) (1-butyl-3-methylimidazolium tetrafluoroborate) that enhances the conductivity, and chitosan (CHI), that facilitates the enzyme immobilization. The biosensor ([CHI+IL/CuPcS]2-GAO) results from the immobilization of galactose oxidase on the top of the LbL layers. FTIR, UV–vis, and AFM have confirmed the proposed structure and cyclic voltammetry has demonstrated the amplification caused by the combination of materials in the film. Sensors have been combined to form an electronic tongue for milk analysis. Principal component analysis has revealed the ability of the sensor system to discriminate between milk samples with different lactose content. Using a PLS-1 calibration models, correlations have been found between the voltammetric signals and chemical parameters measured by classical methods. PLS-1 models provide excellent correlations with lactose content. Additional information about other components, such as fats, proteins, and acidity, can also be obtained. The method developed is simple, and the short response time permits its use in assaying milk samples online.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project AGL2015-67482-R)Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (project VA-011U16)Junta de Castilla y León (grant BOCYL-D-4112015-9
Glacial morphology and evolution in the Cornión Massif (Picos de Europa, Cantabrian Mountains)
[Resumen] En este artículo se analizan la morfología y las fases glaciares reconocibles en el Macizo Occidental de los Picos de Europa, a partir de los depósitos y formas erosivas conservadas, de las relaciones morfoestratigráficas entre dichas evidencias, así como de la realización de dataciones absolutas de C14 en secuencias sedimentarias asociadas. Los resultados del mismo son la identificación de cuatro fases glaciares principales desde la Última Glaciación: Fase de Máxima Extensión del Hielo (MEH, con ocho glaciares), Fase Interna (con ocho glaciares),
Fase Glaciar de Altitud (Tardiglaciar, con 37 glaciares) y Fase de glaciares de fondo de circo
(Pequeña Edad del Hielo, con tres glaciares). La superficie glaciada en cada una de ellas
fue de 7.329,8, 5.842,9, 797,4 y 10 ha respectivamente. Para las dos primeras se han obtenido
edades mínimas de 36.718±1.203 y 11.150±900 años cal BP. Se confirma nuevamente la
antecedencia en la MEH dentro de la Última Glaciación de los glaciares generados en las
Montañas Cantábricas con respecto al Último Máximo Glaciar Global[Abstract] This paper examines the glacial morphology and glacial stages of the Western Massif of the Picos de Europa, through the study of the preserved deposits and erosive landforms, the morphostratigraphic relationships between these evidences, as well as 14C datings in related sedimentary sequences. The main results are the identification of four main glacial stages since the Last Glaciation: Maximum Glacial Advance (eight glaciers), Glacial Expansion after the Maximum Advance (eight glaciers), Late Glacial (37 glaciers) and Little Ice Age
(three glaciers). The glaciated surface in each of them was 7,329.8, 5,842.9, 797.4 and 10 ha,
respectively. For the first two glacial stages, minimum ages of 36,718±1,203 and 11,150±900
years BP were obtained. As in previous studies, the asynchronicity between the Maximum Ice
Extent within the Last Glaciation of the Cantabrian glaciers with respect to the global Last
Glacial Maximum is confirme
The Royal Asturian Mining Company and the development of zinc architecture in the North of Spain in the early 20th Century
The snowstorms of 1888 in Asturias: social and institutional response
Los temporales de nieve de 1888 generaron un daño sin precedentes en la historia reciente de Asturias. Esta investigación, basada en el análisis de fuentes históricas, indaga en la reacción de los grupos humanos que se vieron afectados, examinando tanto la respuesta ofrecida por las instituciones como las estrategias de adaptación y manejo del riesgo por parte de quienes habitaban en las áreas más damnificadas. Los resultados evidencian la mala gestión de la crisis por parte de las autoridades, que centraron sus esfuerzos en aliviar la situación de incomunicación con el exterior de la región y ofrecieron ayudas económicas insuficientes. En las áreas de montaña, sin embargo, rasgos como la cultura del trabajo comunal y la solidaridad vecinal evidenciaron su utilidad desde el punto de vista organizacional, mostrándose como el mecanismo paliativo más eficiente, única respuesta inmediata ante el desastre, capaz de llegar a la totalidad del territorio afectado.The snowstorms of 1888 caused unprecedented damage in the recent history of Asturias. This research, based on an analysis of historical sources, investigates the response of the affected society. It examines both the response of the state organisations, and the adaptation and risk management strategies of those who lived in the most affected areas. The results show poor management of the crisis by the authorities, who focused their efforts on restoring rail and road communications and offered scarce economic aid. In the mountain areas, however, a communal work culture and neighbourhood solidarity, were useful from the organisational point of view, and can be considered the most efficient palliatives and the only immediate responses capable of reaching the entire affected territory.El presente trabajo se ha realizado bajo el apoyo de las becas de investigación Ramón de la Sagra (concedida por la Fundación Alvargonzález) y del programa FPU del Ministerio de Educación, Cultura y Deporte [número de contrato MECD-15-FPU14/01279]. La autora agradece su apoyo a Kaleidos, a la Fundación Alvargonzález por la concesión de la Beca Ramón de la Sagra, y al programa FPU del Ministerio de Educación, Cultura y Deporte [número de contrato MECD-15-FPU14/01279]
Topographic and geomorphologic controls on the distribution of vegetation formations in Elephant Point (Livingston Island, Maritime Antarctica)
This article focuses on the spatial distribution of vegetation formations in Elephant Point, an ice-free area of 1.16km2 located in Livingston Island (South Shetland Islands, Antarctica). Fieldwork carried out in January 2014 consisted of floristic surveys and designation of a vegetation map. We have examined these data in a GIS environment together with topographical and geomorphological features existing in the peninsula in order to infer the factors controlling vegetation distribution. This has allowed quantifying the total area covered by the four different vegetation formations distributed across the peninsula, proliferating mainly on bedrock plateaus and Holocene raised beaches. Grass formation is essentially composed of Deschampsia antarctica, distributed almost exclusively on raised beaches, and covering 4.1% of the ice-free surface. The remaining three formations are fundamentally composed of cryptogam species. The first of which is fruticose lichen and moss formation, present on high bedrock plateaus and principally formed by lichens such as Usnea aurantiaco-atra. The next is the crustose lichen formation, spreading on bedrock plateaus near the coast populated by bird colonies. In this case, ornitocoprophilous lichens such as Caloplaca regalis, Xanthoria elegans and Haematomma erythromma are predominant. Together, both formations have colonised 5.1% of the peninsula. The last variety, moss carpet and moss cushion formation, occupies 1.4% of the deglaciated surface, spreading primarily in flooded areas, stabilised talus slopes, and bedrock plateaus as well. Therefore, the total surface colonised by vegetation is 12.2ha, which comprises 10.5% of the peninsula. Due to the retreat of the Rotch Dome glacier, 20.1ha remain ice-free since 1956 (17.3% of the deglaciated area). Ever since, even though the Antarctic Peninsula has registered one of the most significant temperature rises on Earth, vegetation has only colonised 0.04ha of this new space, which merely represents 0.3% of the vegetated area in Elephant Point.info:eu-repo/semantics/publishedVersio
Improving antioxidant properties and probiotic effect of clementine juice inoculated with Lactobacillus salivarius spp. salivarius (CECT 4063) by trehalose addition and/or subletal homogenisation
[EN] This study evaluates the effect of trehalose addition (10% or 20%, w/w) and/or sublethal homogenisation (25-150 MPa) on antioxidants content (vitamin C, total phenols and flavonoids) and activity (measured both by ABTS-TEAC and DPPH assays), as well as on microbial counts and survival to in vitro digestion of clementine juice inoculated with Lactobacillus salivarius spp. salivarius. Particle size, vacuum impregnation parameters and anti-Helicobacter pylori effect were also measured. Incubation with the probiotic improved the antioxidant properties of the juice. Homogenisation pressures below 100 MPa following incubation increased both the probiotic counts in the juice and its antioxidants bioaccesibility. Adding 10% (w/w) of trehalose to the juice was effective in preventing these bioactive compounds deterioration under adverse conditions. Once homogenised, liquids containing 10% (w/w) of trehalose became as able as those without trehalose to enter a food solid matrix. Inhibition of Helicobacter pylori growth was evident in all probiotic beverages.This research has been carried out with the financing granted by the Generalitat Valenciana for project GV/2015/066 "Improving the functional quality of a snack with probiotic effect and antioxidant properties through the incorporation of trehalose and the application of high homogenisation pressures".Barrera Puigdollers, C.; Burca, C.; Betoret, E.; García Hernández, J.; Hernández Pérez, M.; Betoret Valls, N. (2019). Improving antioxidant properties and probiotic effect of clementine juice inoculated with Lactobacillus salivarius spp. salivarius (CECT 4063) by trehalose addition and/or subletal homogenisation. International Journal of Food Science & Technology. 54(6):2109-2122. https://doi.org/10.1111/ijfs.14116S21092122546Aiba, Y., Suzuki, N., Kabir, A. M. A., Takagi, A., & Koga, Y. (1998). 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Journal of Food Engineering, 91(2), 305-310. doi:10.1016/j.jfoodeng.2008.09.008Basson, A., Flemming, L. A., & Chenia, H. Y. (2007). Evaluation of Adherence, Hydrophobicity, Aggregation, and Biofilm Development of Flavobacterium johnsoniae-Like Isolates. Microbial Ecology, 55(1), 1-14. doi:10.1007/s00248-007-9245-yBermejo, A., & Cano, A. (2012). Analysis of Nutritional Constituents in Twenty Citrus Cultivars from the Mediterranean Area at Different Stages of Ripening. Food and Nutrition Sciences, 03(05), 639-650. doi:10.4236/fns.2012.35088Betoret, N., Puente, L., Dı́az, M. ., Pagán, M. ., Garcı́a, M. ., Gras, M. ., … Fito, P. (2003). Development of probiotic-enriched dried fruits by vacuum impregnation. Journal of Food Engineering, 56(2-3), 273-277. doi:10.1016/s0260-8774(02)00268-6Betoret, E., Betoret, N., Carbonell, J. V., & Fito, P. (2009). Effects of pressure homogenization on particle size and the functional properties of citrus juices. Journal of Food Engineering, 92(1), 18-23. doi:10.1016/j.jfoodeng.2008.10.028Betoret, E., Sentandreu, E., Betoret, N., & Fito, P. (2012). Homogenization pressures applied to citrus juice manufacturing. Functional properties and application. Journal of Food Engineering, 111(1), 28-33. doi:10.1016/j.jfoodeng.2012.01.035Betoret, E., Betoret, N., Arilla, A., Bennár, M., Barrera, C., Codoñer, P., & Fito, P. (2012). No invasive methodology to produce a probiotic low humid apple snack with potential effect against Helicobacter pylori. Journal of Food Engineering, 110(2), 289-293. doi:10.1016/j.jfoodeng.2011.04.027Betoret, E., Betoret, N., Castagnini, J. M., Rocculi, P., Dalla Rosa, M., & Fito, P. (2015). Analysis by non-linear irreversible thermodynamics of compositional and structural changes occurred during air drying of vacuum impregnated apple (cv. Granny smith): Calcium and trehalose effects. 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Stability of probiotics encapsulated with Thai herbal extracts in fruit juices and yoghurt during refrigerated storage. Food Bioscience, 12, 61-66. doi:10.1016/j.fbio.2015.07.006Chen, M., & Mustapha, A. (2012). Survival of freeze-dried microcapsules of α-galactosidase producing probiotics in a soy bar matrix. Food Microbiology, 30(1), 68-73. doi:10.1016/j.fm.2011.10.017Cho, K. M., Lee, J. H., Yun, H. D., Ahn, B. Y., Kim, H., & Seo, W. T. (2011). Changes of phytochemical constituents (isoflavones, flavanols, and phenolic acids) during cheonggukjang soybeans fermentation using potential probiotics Bacillus subtilis CS90. Journal of Food Composition and Analysis, 24(3), 402-410. doi:10.1016/j.jfca.2010.12.015Chung, I.-M., Seo, S.-H., Ahn, J.-K., & Kim, S.-H. (2011). Effect of processing, fermentation, and aging treatment to content and profile of phenolic compounds in soybean seed, soy curd and soy paste. Food Chemistry, 127(3), 960-967. doi:10.1016/j.foodchem.2011.01.065Carmen Collado, M., & Hernández, M. (2007). Identification and differentiation of Lactobacillus, Streptococcus and Bifidobacterium species in fermented milk products with bifidobacteria. Microbiological Research, 162(1), 86-92. doi:10.1016/j.micres.2006.09.007Collado, M. C., Moreno, Y., Hernández, E., Cobo, J. M., & Hernández, M. (2005). Note. In Vitro Viability of Bifidobacterium Strains Isolated from Commercial Dairy Products Exposed to Human Gastrointestinal Conditions. Food Science and Technology International, 11(4), 307-314. doi:10.1177/1082013205056559Corredig, M., Kerr, W., & Wicker, L. (2001). Particle Size Distribution of Orange Juice Cloud after Addition of Sensitized Pectin. Journal of Agricultural and Food Chemistry, 49(5), 2523-2526. doi:10.1021/jf001087aCROWE, J. H., CROWE, L. M., & CHAPMAN, D. (1984). Preservation of Membranes in Anhydrobiotic Organisms: The Role of Trehalose. Science, 223(4637), 701-703. doi:10.1126/science.223.4637.701Dueñas, M., Fernández, D., Hernández, T., Estrella, I., & Muñoz, R. (2004). Bioactive phenolic compounds of cowpeas (Vigna sinensisL). Modifications by fermentation with natural microflora and withLactobacillus plantarumATCC 14917. Journal of the Science of Food and Agriculture, 85(2), 297-304. doi:10.1002/jsfa.1924Fabroni, S., Romeo, F. V., & Rapisarda, P. (2016). Nutritional Composition of Clementine ( Citrus x clementina ) Cultivars. Nutritional Composition of Fruit Cultivars, 149-172. doi:10.1016/b978-0-12-408117-8.00007-6Fito, P., Chiralt, A., Barat, J. M., Andrés, A., Martı́nez-Monzó, J., & Martı́nez-Navarrete, N. (2001). Vacuum impregnation for development of new dehydrated products. Journal of Food Engineering, 49(4), 297-302. doi:10.1016/s0260-8774(00)00226-0Martins, E. M. F., Ramos, A. M., Vanzela, E. S. L., Stringheta, P. C., de Oliveira Pinto, C. L., & Martins, J. M. (2013). Products of vegetable origin: A new alternative for the consumption of probiotic bacteria. Food Research International, 51(2), 764-770. doi:10.1016/j.foodres.2013.01.047García-Hernández, J., Moreno, Y., Chuan, C., & Hernández, M. (2012). In VivoStudy of the Survival ofLactobacillus delbrueckisubsp.bulgaricusCECT 4005T andStreptococcus thermophilusCECT 801 by DVC-FISH after Consumption of Fermented Milk. Journal of Food Science, 77(10), M593-M597. doi:10.1111/j.1750-3841.2012.02918.xGarcía-Hernández, J., Hernández-Pérez, M., Peinado, I., Andrés, A., & Heredia, A. (2018). Tomato-antioxidants enhance viability of L. reuteri under gastrointestinal conditions while the probiotic negatively affects bioaccessibility of lycopene and phenols. Journal of Functional Foods, 43, 1-7. doi:10.1016/j.jff.2017.12.052Hole, A. S., Rud, I., Grimmer, S., Sigl, S., Narvhus, J., & Sahlstrøm, S. (2012). Improved Bioavailability of Dietary Phenolic Acids in Whole Grain Barley and Oat Groat following Fermentation with Probiotic Lactobacillus acidophilus, Lactobacillus johnsonii, and Lactobacillus reuteri. Journal of Agricultural and Food Chemistry, 60(25), 6369-6375. doi:10.1021/jf300410hKaushik, J. K., & Bhat, R. (2003). Why Is Trehalose an Exceptional Protein Stabilizer? Journal of Biological Chemistry, 278(29), 26458-26465. doi:10.1074/jbc.m300815200Umer Khan, S. (2014). Probiotics in dairy foods: a review. Nutrition & Food Science, 44(1), 71-88. doi:10.1108/nfs-04-2013-0051LANCIOTTI, R., PATRIGNANI, F., IUCCI, L., SARACINO, P., & GUERZONI, M. (2007). Potential of high pressure homogenization in the control and enhancement of proteolytic and fermentative activities of some Lactobacillus species. Food Chemistry, 102(2), 542-550. doi:10.1016/j.foodchem.2006.06.043Lin, W.-H., Wu, C.-R., Fang, T. J., Guo, J.-T., Huang, S.-Y., Lee, M.-S., & Yang, H.-L. (2011). Anti-Helicobacter pylori
activity of fermented milk with lactic acid bacteria. Journal of the Science of Food and Agriculture, 91(8), 1424-1431. doi:10.1002/jsfa.4327Luximon-Ramma, A., Bahorun, T., Crozier, A., Zbarsky, V., Datla, K. P., Dexter, D. T., & Aruoma, O. I. (2005). Characterization of the antioxidant functions of flavonoids and proanthocyanidins in Mauritian black teas. Food Research International, 38(4), 357-367. doi:10.1016/j.foodres.2004.10.005Manojlović, V., Nedović, V. A., Kailasapathy, K., & Zuidam, N. J. (2009). Encapsulation of Probiotics for use in Food Products. Encapsulation Technologies for Active Food Ingredients and Food Processing, 269-302. doi:10.1007/978-1-4419-1008-0_10Mansure, J. J. ., Panek, A. D., Crowe, L. M., & Crowe, J. H. (1994). Trehalose inhibits ethanol effects on intact yeast cells and liposomes. Biochimica et Biophysica Acta (BBA) - Biomembranes, 1191(2), 309-316. doi:10.1016/0005-2736(94)90181-3Da Costa Morato Nery, D., da Silva, C. G., Mariani, D., Fernandes, P. N., Pereira, M. D., Panek, A. D., & Eleutherio, E. C. A. (2008). The role of trehalose and its transporter in protection against reactive oxygen species. Biochimica et Biophysica Acta (BBA) - General Subjects, 1780(12), 1408-1411. doi:10.1016/j.bbagen.2008.05.011Ohtake, S., & Wang, Y. J. (2011). Trehalose: Current Use and Future Applications. Journal of Pharmaceutical Sciences, 100(6), 2020-2053. doi:10.1002/jps.22458Oku, K., Kurose, M., Kubota, M., Fukuda, S., Kurimoto, M., Tujisaka, Y., … Sakurai, M. (2005). Combined NMR and Quantum Chemical Studies on the Interaction between Trehalose and Dienes Relevant to the Antioxidant Function of Trehalose. The Journal of Physical Chemistry B, 109(7), 3032-3040. doi:10.1021/jp045906wPatrignani, F., Vannini, L., Kamdem, S. L. S., Lanciotti, R., & Guerzoni, M. E. (2009). Effect of high pressure homogenization on Saccharomyces cerevisiae inactivation and physico-chemical features in apricot and carrot juices. International Journal of Food Microbiology, 136(1), 26-31. doi:10.1016/j.ijfoodmicro.2009.09.021Pirbaglou, M., Katz, J., de Souza, R. J., Stearns, J. C., Motamed, M., & Ritvo, P. (2016). Probiotic supplementation can positively affect anxiety and depressive symptoms: a systematic review of randomized controlled trials. Nutrition Research, 36(9), 889-898. doi:10.1016/j.nutres.2016.06.009Homayouni Rad, A., Torab, R., Mortazavian, A. M., Mehrabany, E. V., & Mehrabany, L. V. (2013). Can probiotics prevent or improve common cold and influenza? Nutrition, 29(5), 805-806. doi:10.1016/j.nut.2012.10.009Ranadheera, R. D. C. S., Baines, S. K., & Adams, M. C. (2010). Importance of food in probiotic efficacy. Food Research International, 43(1), 1-7. doi:10.1016/j.foodres.2009.09.009Re, R., Pellegrini, N., Proteggente, A., Pannala, A., Yang, M., & Rice-Evans, C. (1999). Antioxidant activity applying an improved ABTS radical cation decolorization assay. Free Radical Biology and Medicine, 26(9-10), 1231-1237. doi:10.1016/s0891-5849(98)00315-3Rivera-Espinoza, Y., & Gallardo-Navarro, Y. (2010). Non-dairy probiotic products. Food Microbiology, 27(1), 1-11. doi:10.1016/j.fm.2008.06.008Rouxinol-Dias, A. L., Pinto, A. R., Janeiro, C., Rodrigues, D., Moreira, M., Dias, J., & Pereira, P. (2016). Probiotics for the control of obesity – Its effect on weight change. Porto Biomedical Journal, 1(1), 12-24. doi:10.1016/j.pbj.2016.03.005SALVATORI, D., ANDRÉS, A., CHIRALT, A., & FITO, P. (1998). THE RESPONSE OF SOME PROPERTIES OF FRUITS TO VACUUM IMPREGNATION. Journal of Food Process Engineering, 21(1), 59-73. doi:10.1111/j.1745-4530.1998.tb00439.xSanders, M. E. (2008). Probiotics: Definition, Sources, Selection, and Uses. Clinical Infectious Diseases, 46(s2), S58-S61. doi:10.1086/523341Shah, N. P., Ding, W. K., Fallourd, M. J., & Leyer, G. (2010). Improving the Stability of Probiotic Bacteria in Model Fruit Juices Using Vitamins and Antioxidants. Journal of Food Science, no-no. doi:10.1111/j.1750-3841.2010.01628.xTabanelli, G., Burns, P., Patrignani, F., Gardini, F., Lanciotti, R., Reinheimer, J., & Vinderola, G. (2012). Effect of a non-lethal High Pressure Homogenization treatment on the in vivo response of probiotic lactobacilli. Food Microbiology, 32(2), 302-307. doi:10.1016/j.fm.2012.07.004Tabanelli, G., Patrignani, F., Vinderola, G., Reinheimer, J. A., Gardini, F., & Lanciotti, R. (2013). Effect of sub-lethal high pressure homogenization treatments on the in vitro functional and biological properties of lactic acid bacteria. LWT - Food Science and Technology, 53(2), 580-586. doi:10.1016/j.lwt.2013.03.013Wolkers, W. F., Walker, N. J., Tablin, F., & Crowe, J. H. (2001). Human Platelets Loaded with Trehalose Survive Freeze-Drying. Cryobiology, 42(2), 79-87. doi:10.1006/cryo.2001.230
Control of V(D)J Recombination through Transcriptional Elongation and Changes in Locus Chromatin Structure and Nuclear Organization
V(D)J recombination is the assembly of gene segments at the antigen receptor loci to
generate antigen receptor diversity in T and B lymphocytes. This process is regulated,
according to defined developmental programs, by the action of a single specific
recombinase complex formed by the recombination antigen gene (RAG-1/2) proteins
that are expressed in immature lymphocytes. V(D)J recombination is strictly controlled
by RAG-1/2 accessibility to specific recombination signal sequences in chromatin at
several levels: cellular lineage, temporal regulation, gene segment order, and allelic
exclusion. DNA cleavage by RAG-1/2 is regulated by the chromatin structure,
transcriptional elongation, and three-dimensional architecture and position of the
antigen receptor loci in the nucleus. Cis-elements specifically direct transcription and
V(D)J recombination at these loci through interactions with transacting factors that form
molecular machines that mediate a sequence of structural events. These events open
chromatin to activate transcriptional elongation and to permit the access of RAG-1/2 to
their recombination signal sequences to drive the juxtaposition of the V, D, and J
segments and the recombination reaction itself. This chapter summarizes the advances
in this area and the important role of the structure and position of antigen receptor loci
within the nucleus to control this process
Late-onset thymidine kinase 2 deficiency: a review of 18 cases
BACKGROUND: TK2 gene encodes for mitochondrial thymidine kinase, which phosphorylates the pyrimidine nucleosides thymidine and deoxycytidine. Recessive mutations in the TK2 gene are responsible for the 'myopathic form' of the mitochondrial depletion/multiple deletions syndrome, with a wide spectrum of severity. METHODS: We describe 18 patients with mitochondrial myopathy due to mutations in the TK2 gene with absence of clinical symptoms until the age of 12. RESULTS: The mean age of onset was 31 years. The first symptom was muscle limb weakness in 10/18, eyelid ptosis in 6/18, and respiratory insufficiency in 2/18. All patients developed variable muscle weakness during the evolution of the disease. Half of patients presented difficulty in swallowing. All patients showed evidence of respiratory muscle weakness, with need for non-invasive Mechanical Ventilation in 12/18. Four patients had deceased, all of them due to respiratory insufficiency. We identified common radiological features in muscle magnetic resonance, where the most severely affected muscles were the gluteus maximus, semitendinosus and sartorius. On muscle biopsies typical signs of mitochondrial dysfunction were associated with dystrophic changes. All mutations identified were previously reported, being the most frequent the in-frame deletion p.Lys202del. All cases showed multiple mtDNA deletions but mtDNA depletion was present only in two patients. CONCLUSIONS: The late-onset is the less frequent form of presentation of the TK2 deficiency and its natural history is not well known. Patients with late onset TK2 deficiency have a consistent and recognizable clinical phenotype and a poor prognosis, due to the high risk of early and progressive respiratory insufficiency.Instituto de Salud Carlos III PI16-01843 PI16/00579 CP09/00011Subdirección General de Evaluación y Fomento de la Investigación Sanitaria PI16-01843 PI16/00579 CP09/00011 PI 15/00431 PMP15/0002
Biosensors Platform Based on Chitosan/AuNPs/Phthalocyanine Composite Films for the Electrochemical Detection of Catechol. The Role of the Surface Structure
Producción CientíficaBiosensor platforms consisting of layer by layer films combining materials with different functionalities have been developed and used to obtain improved catechol biosensors. Tyrosinase (Tyr) or laccase (Lac) were deposited onto LbL films formed by layers of a cationic linker (chitosan, CHI) alternating with layers of anionic electrocatalytic materials (sulfonated copper phthalocyanine, CuPcS or gold nanoparticles, AuNP). Films with different layer structures were successfully formed. Characterization of surface roughness and porosity was carried out using AFM. Electrochemical responses towards catechol showed that the LbL composites efficiently improved the electron transfer path between Tyr or Lac and the electrode surface, producing an increase in the intensity over the response in the absence of the LbL platform. LbL structures with higher roughness and pore size facilitated the diffusion of catechol, resulting in lower LODs. The [(CHI)-(AuNP)-(CHI)-(CuPcS)]2-Tyr showed an LOD of 8.55∙10−4 μM, which was one order of magnitude lower than the 9.55·10−3 µM obtained with [(CHI)-(CuPcS)-(CHI)-(AuNP)]2-Tyr, and two orders of magnitude lower than the obtained with other nanostructured platforms. It can be concluded that the combination of adequate materials with complementary activity and the control of the structure of the platform is an excellent strategy to obtain biosensors with improved performances.Ministerio de Ciencia, Innovación y Universidades - Fondo Europeo de Desarrollo Regional (project RTI2018-097990-B-100)Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (project VA275P18)Infraestructuras Red de Castilla y León (grant UVA01
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