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La microbiota intestinal, constituida por una diversidad de microorganismo, juega un papel crucial en la salud, incluyendo funciones metabólicas, inmunológicas y protectoras contra patógenos. Sin embargo, su alteración o disbiosis ha sido asociado con diversos canceres hereditarios, como el cáncer colorrectal, de mama y ovario. El cáncer colorrectal hereditario incluye el síndrome Lynch y la poliposis adenomatosa familiar, ambos asociados a mutaciones genéticas, como en los genes MLH1 y MSH2 en el síndrome de Lynch, que predisponen a la formación de tumores. Mientras que los genes BRCA1 y BRCA2 son los más estudiados en relación con el cáncer de mama y ovario hereditario. La relación entre la microbiota y el cáncer hereditario es bidireccional: la microbiota puede influir en la carcinogénesis a través de mecanismo pro-tumorales y antitumorales. Por ejemplo, bacterias como Helicobacter pylori y Escherichia coli producen toxinas que inducen daño en el ADN y promueven la inflamación crónica. Por otro lado, metabolitos como el butirato y propionato, han demostrado tener efectos antitumorales al inhibir la proliferación celular y promover respuestas inmunitarias contra las células tumorales. Una dieta alta en grasa, azucares y alimentos procesados aumenta el riesgo de cáncer, mientras que la dieta mediterránea ofrece porrección contra varias enfermedades, incluyendo ciertos canceres. Las dietas vegetarianas también tienen propiedades anticancerígenas debido a su alto contenido en antioxidantes. Por lo tanto, la intervención nutricional dirigida a modificar la microbiota podría representar una vía prometedora para la prevención y el manejo del cáncer en pacientes con predisposición genética., Grado en Nutrición Humana y Dietética

The microbiota is attributed to be important for initial soil formation under extreme climate conditions, but experimental evidence for its relevance is scarce. To fill this gap, we investigated the impact of in situ microbial communities and their interrelationship with biocrust and plants compared to abiotic controls on soil formation in initial arid and semiarid soils. Additionally, we assessed the response of bacterial communities to climate change. Topsoil and subsoil samples from arid and semiarid sites in the Chilean Coastal Cordillera were incubated for 16 weeks under diurnal temperature and moisture variations to simulate humid climate conditions as part of a climate change scenario. Our findings indicate that microorganism-plant interaction intensified aggregate formation and stabilized soil structure, facilitating initial soil formation. Interestingly, microorganisms alone or in conjunction with biocrust showed no discernible patterns compared to abiotic controls, potentially due to water-masking effects. Arid soils displayed reduced bacterial diversity and developed a new community structure dominated by Proteobacteria, Actinobacteriota, and Planctomycetota, while semiarid soils maintained a consistently dominant community of Acidobacteriota and Proteobacteria. This highlighted a sensitive and specialized bacterial community in arid soils, while semiarid soils exhibited a more complex and stable community. We conclude that microorganism-plant interaction has measurable impacts on initial soil formation in arid and semiarid regions on short time scales under climate change. Additionally, we propose that soil and climate legacies are decisive for the present soil microbial community structure and interactions, future soil development, and microbial responses.

En este trabajo de fin de grado se ha realizado un estudio de mercado del sector turismo relacionándolo con los estilos de vida y el nicho hotelero. La razón de este reside en encontrar información acerca del impacto de los estilos de vida en la elección de destinos turísticos y el comportamiento del turista. Cada apartado del trabajo se aborda desde la perspectiva del marketing.

[Background] A history of childhood adversity is associated with psychotic disorder, with an increase in risk according to the number of exposures. However, it is not known why only some exposed individuals go on to develop psychosis. One possibility is pre-existing polygenic vulnerability. Here, we investigated, in the largest sample of first-episode psychosis (FEP) cases to date, whether childhood adversity and high polygenic risk scores for schizophrenia (SZ-PRS) combine synergistically to increase the risk of psychosis, over and above the effect of each alone., [Methods] We assigned a schizophrenia-polygenic risk score (SZ-PRS), calculated from the Psychiatric Genomics Consortium (PGC2), to all participants in a sample of 384 FEP patients and 690 controls from the case–control component of the EU-GEI study. Only participants of European ancestry were included in the study. A history of childhood adversity was collected using the Childhood Trauma Questionnaire (CTQ). Synergistic effects were estimated using the interaction contrast ratio (ICR) [odds ratio (OR)exposure and PRS − ORexposure − ORPRS + 1] with adjustment for potential confounders., [Results] There was some evidence that the combined effect of childhood adversities and polygenic risk was greater than the sum of each alone, as indicated by an ICR greater than zero [i.e. ICR 1.28, 95% confidence interval (CI) −1.29 to 3.85]. Examining subtypes of childhood adversities, the strongest synergetic effect was observed for physical abuse (ICR 6.25, 95% CI −6.25 to 20.88)., [Conclusions] Our findings suggest possible synergistic effects of genetic liability and childhood adversity experiences in the onset of FEP, but larger samples are needed to increase precision of estimates.

Despite the accepted link between childhood adversity (CA) and psychotic disorders, evidence on the relationship between CA and poor functional outcome remains less consistent and has never been reviewed quantitatively. The aim of this meta-analysis was to systematically examine the association between CA and functional outcomes in people with psychotic disorders.

[Background] Early-onset psychosis (EOP) refers to the development of a first episode of psychosis before 18 years of age. Individuals at clinical high risk for psychosis (CHR-P) include adolescents and young adults, although most evidence has focused on adults. Negative symptoms are important prognostic indicators in psychosis. However, research focusing on children and adolescents is limited., [Aims] To provide meta-analytical evidence and a comprehensive review of the status and advances in the diagnosis, prognosis and treatment of negative symptoms in children and adolescents with EOP and at CHR-P., [Method] PRISMA/MOOSE-compliant systematic review (PROSPERO: CRD42022360925) from inception to 18 August 2022, in any language, to identify individual studies conducted in EOP/CHR-P children and adolescents (mean age <18 years) providing findings on negative symptoms. Findings were systematically appraised. Random-effects meta-analyses were performed on the prevalence of negative symptoms, carrying out sensitivity analyses, heterogeneity analyses, publication bias assessment and quality assessment using the Newcastle–Ottawa Scale., [Results] Of 3289 articles, 133 were included (n = 6776 EOP, mean age 15.3 years (s.d. = 1.6), males = 56.1%; n = 2138 CHR-P, mean age 16.1 years (s.d. = 1.0), males = 48.6%). There were negative symptoms in 60.8% (95% CI 46.4%–75.2%) of the children and adolescents with EOP and 79.6% (95% CI 66.3–92.9%) of those at CHR-P. Prevalence and severity of negative symptoms were associated with poor clinical, functional and intervention outcomes in both groups. Different interventions were piloted, with variable results requiring further replication., [Conclusions] Negative symptoms are common in children and adolescents at early stages of psychosis, particularly in those at CHR-P, and are associated with poor outcomes. Future intervention research is required so that evidence-based treatments will become available.