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1.
PeerJ ; 12: e16936, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435985

RESUMEN

Reticulitermes flavipes, one of the most destructive subterranean termite species, has been detected for the first time in an arid territory: Lanzarote (Canary Islands, Spain). This invasive species was introduced into several countries but never such a dry region. Although there are places with presence of this termite at similar or even higher temperatures, none has annual rainfall (10.1 mm) as low as Lanzarote. On this island it is present in semi-desert, near an affected urban area. Distribution, genetic, climate and host-plant data are evaluated to track and understand its invasion process in the archipelago.


Asunto(s)
Cucarachas , Isópteros , Animales , Clima , Especies Introducidas , España
2.
Sci Rep ; 12(1): 19344, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36369519

RESUMEN

Volcanic activity provides a unique opportunity to study the ecological responses of organisms to catastrophic environmental destruction as an essential driver of biodiversity change on islands. However, despite this great scientific interest, no study of the biodiversity at an erupting volcano has yet been undertaken. On La Palma (Canary archipelago), we quantified the main species affected and their fate during the 85-day eruption (September-December 2021). Our main objective consisted of monitoring the biodiversity subjected to critical stress during this volcanic eruption. We found that all biodiversity within a 2.5 km radius was severely affected after the first two weeks. It is challenging to assess whether volcanism can drive evolutionary traits of insular organisms. Examples are the adaptation of an endemic conifer to high temperatures, selection of functional plant types-secondary woodiness-, effects of the disappearance of invertebrates and their influence in trophic nets and vertebrate trophic plasticity. However, our data suggest that such previous evolutionary changes might continue to favour their resilience during this eruption. Lastly, it is a very good opportunity to assess the extent to which these periodic volcanic catastrophes may constitute temporary windows of repeated opportunities for the evolution and speciation of oceanic island biota.


Asunto(s)
Biodiversidad , Erupciones Volcánicas , Animales , Islas , Océanos y Mares , Invertebrados
3.
PLoS One ; 7(1): e30812, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22292045

RESUMEN

In colorectal cancer (CRC), an inherited susceptibility risk affects about 35% of patients, whereas high-penetrance germline mutations account for <6% of cases. A considerable proportion of sporadic tumors could be explained by the coinheritance of multiple low-penetrance variants, some of which are common. We assessed the susceptibility to CRC conferred by genetic variants at the TGFBR1 locus. We analyzed 14 polymorphisms and the allele-specific expression (ASE) of TGFBR1 in 1025 individuals from the Spanish population. A case-control study was undertaken with 504 controls and 521 patients with sporadic CRC. Fourteen polymorphisms located at the TGFBR1 locus were genotyped with the iPLEX Gold (MassARRAY-Sequenom) technology. Descriptive analyses of the polymorphisms and haplotypes and association studies were performed with the SNPator workpackage. No relevant associations were detected between individual polymorphisms or haplotypes and the risk of CRC. The TGFBR1*9A/6A polymorphism was used for the ASE analysis. Heterozygous individuals were analyzed for ASE by fragment analysis using cDNA from normal tissue. The relative level of allelic expression was extrapolated from a standard curve. The cutoff value was calculated with Youden's index. ASE was found in 25.4% of patients and 16.4% of controls. Considering both bimodal and continuous types of distribution, no significant differences between the ASE values of patients and controls were identified. Interestingly, a combined analysis of the polymorphisms and ASE for the association with CRC occurrence revealed that ASE-positive individuals carrying one of the most common haplotypes (H2: 20.7%) showed remarkable susceptibility to CRC (RR: 5.25; 95% CI: 2.547-5.250; p<0.001) with a synergy factor of 3.7. In our study, 54.1% of sporadic CRC cases were attributable to the coinheritance of the H2 haplotype and TGFBR1 ASE. These results support the hypothesis that the allelic architecture of cancer genes, rather than individual polymorphisms, more accurately defines the CRC risk.


Asunto(s)
Carcinoma/genética , Neoplasias Colorrectales/genética , Epistasis Genética/fisiología , Sitios Genéticos , Proteínas Serina-Treonina Quinasas/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/epidemiología , Estudios de Casos y Controles , Neoplasias Colorrectales/epidemiología , Femenino , Sitios Genéticos/genética , Sitios Genéticos/fisiología , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/fisiología , Factores de Riesgo , Adulto Joven
4.
J Pharm Sci ; 94(7): 1552-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15920772

RESUMEN

Polymeric nanocapsules (NCs) containing octyl methoxycinnamate (OMC) as lipophilic molecule were prepared, and their in vivo distribution profile through the stratum corneum (SC) was determined by the tape-stripping technique. Penetration degree of OMC formulated in NCs was compared with that obtained for a nanoemulsion (NE), and a conventional oil-in-water (o/w) emulsion (EM). To produce stable cellulose acetate phthalate (CAP) nanocapsules containing the lipophilic sunscreen, a study was conducted to optimize the process of NC preparation based on the emulsification-diffusion technique. NC formation was verified by measuring their density using differential centrifugation. NC density revealed that an OMC (microL)/CAP (mg) ratio of 2.5:1 is optimal for encapsulation. High encapsulation entrapment (>96%) and excellent process efficiency (recovered quantity of NCs in relation with the initial amount of OMC and CAP >99%) were always achieved with this ratio or a higher one. The capsular structure of the NCs was evidenced with a direct SEM technique. NE was prepared by the emulsification-diffusion technique, dissolving a specific quantity of OMC in water-saturated 2-butanone and then, emulsifying with an aqueous solution of PVAL. In vivo percutaneous penetration, evaluated by the tape-stripping technique, demonstrated that NE increased the extent of OMC penetration relative to the penetration achieved by NCs or EM, with relative penetration depths through the SC of 0.86 +/- 0.1, 0.64 +/- 0.11, and 0.57 +/- 0.08, respectively. In the same manner, the accumulation in the skin of OMC was significantly greater with NE than with EM or NCs. OMC penetration depth was strongly dependent upon the size of the colloidal particles and their flexibility.


Asunto(s)
Cápsulas/química , Cinamatos/química , Absorción Cutánea , Adulto , Calibración , Celulosa/análogos & derivados , Química Farmacéutica , Difusión , Estabilidad de Medicamentos , Emulsiones , Femenino , Humanos , Masculino , Microscopía Electrónica de Rastreo , Tamaño de la Partícula
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