Heavy metals contaminating the environment of a progressive supranuclear palsy cluster induce tau accumulation and cell death in cultured neurons

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by the presence of intracellular aggregates of tau protein and neuronal loss leading to cognitive and motor impairment. Occurrence is mostly sporadic, but rare family clusters have been described. Although the etiopathology of PSP is unknown, mutations in the MAPT/tau gene and exposure to environmental toxins can increase the risk of PSP. Here, we used cell models to investigate the potential neurotoxic effects of heavy metals enriched in a highly industrialized region in France with a cluster of sporadic PSP cases. We found that iPSC-derived iNeurons from a MAPT mutation carrier tend to be more sensitive to cell death induced by chromium (Cr) and nickel (Ni) exposure than an isogenic control line. We hypothesize that genetic variations may predispose to neurodegeneration induced by those heavy metals. Furthermore, using an SH-SY5Y neuroblastoma cell line, we showed that both heavy metals induce cell death by an apoptotic mechanism. Interestingly, Cr and Ni treatments increased total and phosphorylated tau levels in both cell types, implicating Cr and Ni exposure in tau pathology. Overall, this study suggests that chromium and nickel could contribute to the pathophysiology of tauopathies such as PSP by promoting tau accumulation and neuronal cell death

Variation in Wolbachia cidB gene, but not cidA, is associated with cytoplasmic incompatibility mod phenotype diversity in Culex pipiens

Endosymbiotic Wolbachia bacteria are, to date, considered the most widespread symbionts in arthropods and are the cornerstone of major biological control strategies. Such a high prevalence is based on the ability of Wolbachia to manipulate their hosts' reproduction. One manipulation called cytoplasmic incompatibility (CI) is based on the death of the embryos generated by crosses between infected males and uninfected females or between individuals infected with incompatible Wolbachia strains. CI can be seen as a modification-rescue system (or mod-resc) in which paternal Wolbachia produce mod factors, inducing embryonic defects, unless the maternal Wolbachia produce compatible resc factors. Transgenic experiments in Drosophila melanogaster and Saccharomyces cerevisiae converged towards a model where the cidB Wolbachia gene is involved in the mod function while cidA is involved in the resc function. However, as cidA expression in Drosophila males was required to observe CI, it has been proposed that cidA could be involved in both resc and mod functions. A recent correlative study in natural Culex pipiens mosquito populations has revealed an association between specific cidA and cidB variations and changes in mod phenotype, also suggesting a role for both these genes in mod diversity. Here, by studying cidA and cidB genomic repertoires of individuals from newly sampled natural C. pipiens populations harbouring wPipIV strains from North Italy, we reinforce the link between cidB variation and mod phenotype variation fostering the involvement of cidB in the mod phenotype diversity. However, no association between any cidA variants or combination of cidA variants and mod phenotype variation was observed. Taken together our results in natural C. pipiens populations do not support the involvement of cidA in mod phenotype variation

PWD/Ph-encoded genetic variants modulate the cellular Wnt/β-Catenin response to suppress ApcMin-triggered intestinal tumor formation

Genetic predisposition affects the penetrance of tumor-initiating mutations, such as APC mutations that stabilize β-catenin and cause intestinal tumors in mice and humans. However, the mechanisms involved in genetically predisposed penetrance are not well understood. Here, we analyzed tumor multiplicity and gene expression in tumor-prone ApcMin/+ mice on highly variant C57BL/6J (B6) and PWD/Ph (PWD) genetic backgrounds. (B6 × PWD) F1 APCMin offspring mice were largely free of intestinal adenoma, and several chromosome substitution (consomic) strains carrying single PWD chromosomes on the B6 genetic background displayed reduced adenoma numbers. Multiple dosage-dependent modifier loci on PWD chromosome 5 each contributed to tumor suppression. Activation of β-catenin–driven and stem cell–specific gene expression in the presence of ApcMin or following APC loss remained moderate in intestines carrying PWD chromosome 5, suggesting that PWD variants restrict adenoma initiation by controlling stem cell homeostasis. Gene expression of modifier candidates and DNA methylation on chromosome 5 were predominantly cis controlled and largely reflected parental patterns, providing a genetic basis for inheritance of tumor susceptibility. Human SNP variants of several modifier candidates were depleted in colorectal cancer genomes, suggesting that similar mechanisms may also affect the penetrance of cancer driver mutations in humans. Overall, our analysis highlights the strong impact that multiple genetic variants acting in networks can exert on tumor development

Microbial food web dynamics in response to a Saharan dust event: results from a mesocosm study in the oligotrophic Mediterranean Sea

BiogeosciencesInternational audienceThe significant impact of dust deposition on het-erotrophic bacterial dynamics in the surface oligotrophic ocean has recently been evidenced. Considering the central role of bacteria in the microbial loop, it is likely that dust deposition also affects the structure and the functioning of the whole microbial food web. In the frame of the DUNE project, aiming to estimate the impact of dust deposition on the oligotrophic Mediterranean Sea through mesocosm ex-periments, the main goal of the present paper was to as-sess how two successive dust deposition events affect the dynamics of the microbial food web. The first dust seeding delivered new P and N to the amended mesocosms and re-sulted in a pronounced stimulation of bacterial respiration. It also induced pronounced, but transient, changes in the bac-terial community composition. No significant effects were observed on the abundances of viruses and heterotrophic nanoflagellates. The second dust seeding also delivered new P and N to the amended mesocosms, but the effect on the microbial food web was very different. Bacterial respira-tion remained constant and bacterial abundance decreased. Compositional changes following the second seeding were minor compared to the first one. The decrease in bacterial abundance coincided with an increase in virus abundance, resulting in higher virus : bacteria ratios throughout the sec-ond seeding period. Our study shows that dust deposition to the surface oligotrophic ocean may involve important mod-ifications of the trophic links among the components of the microbial food web with presumed consequences on C and nutrient cycling

Comportamiento del balance estático y dinámico, mediante terapia vibratoria en sujetos jóvenes con antecedentes de esguince de tobillo: una revisión de la literatura

62 p.Objetivos: Revisar la eficacia de la terapia vibratoria en sujetos con inestabilidad funcional de tobillo sobre el balance y propiocepción. Metodología: Se realizó una revisión de la literatura disponible en las bases de datos PubMed, PEDro, y EBSCO, buscando todas las entradas posibles desde enero de 2010 hasta junio de 2020, en idioma español e inglés, utilizando palabras claves y aplicando los criterios de selección elaborados a través de una estrategia PICOT quedando un total de 7 artículos aceptados para la revisión y para la extracción de datos se construyó una tabla personalizada por parte de 2 autores. Resultados: De los 7 estudios válidos para la elaboración de esta revisión 4 eran estudios controlados y los otros 3 consistían en estudios descriptivos donde uno de ellos fue un estudio de laboratorio. Las poblaciones de estudio fueron intervenidas con terapia vibratoria de cuerpo completo, vibración localizada y grupos control. Conclusiones: Ambas modalidades de terapia vibratoria, entregan resultados positivos en el balance en sujetos con inestabilidad funcional de tobillo, complementada con entrenamiento de balance y propiocepción

Horizontal low gradient magnetophoresis behaviour of iron oxide nanoclusters at the different steps of the synthesis route

In this work the use of Horizontal Low Gradient Magnetic Field (HLGMF) (<100T/m) for filtration, control and separation of synthesized magnetic nanoparticles (NPs) is investigated. The characteristics of the suspension, size and type of the NPs are considered and discussed. For these purposes, Fe2O3 silica coated nanoclusters of about 150 nm are synthesized by co-precipitation, monodispersion and silica coating. SQUID, TEM, XRD, and z potential techniques were used to characterize the synthesized nanoclusters. An extensive magnetophoresis study was performed at different magnetophoretical conditions. Different reversible aggregation times were observed at different HLGMF, at each step of the synthesis route. In particular, differences of several orders of magnitude were observed when comparing citric acid modified NPs with silica coated nanoclusters . Reversible aggregation times are correlated to the properties of the NPs at different steps of synthesis route.Fundação para a Ciência e a Tecnologia (FCT) - Bolsa NANO/NMed-SD/0156/2007, PTCD/CTM/69316/2006

Assessment of posttraumatic stress disorder among women after childbirth using the City Birth Trauma Scale in Spain

OBJECTIVE: Postpartum posttraumatic stress disorder (PP-PTSD) affects 3.1-6.3% of women after childbirth. The City Birth Trauma Scale (City-BiTS) is a questionnaire designed to evaluate and diagnose this disorder, according to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria, including the following groups of symptoms characteristic of posttraumatic stress: reexperiencing, avoidance, negative cognitions and mood, and hyperarousal. The aim of the present study was to evaluate the psychometric properties of the Spanish-language version of this questionnaire (City-BiTS-S), based on a community sample of Spanish women. METHOD: A total of 207 mothers, recruited at three health centers in southern Spain, completed the City-BiTS-S questionnaire and provided sociodemographic and obstetric data. RESULTS: Exploratory factor analysis of the data replicated the two-factor structure reported in previous studies that explained 47.9% of the variance: Factor 1 of general symptoms and Factor 2 of birth-related symptoms. Both City-BiTS-S (Cronbach's alpha = .90) and the two factors (Cronbach's alpha for Factor 1 = 0.89; Cronbach's alpha for Factor 2 = 0.82) presented high internal consistency. Rasch analysis confirmed the unidimensionality of the two factors as valid subscales of the PP-PTSD. Results suggested reducing response options, reviewing Item 8, and rewording Item 3 in the Spanish version. CONCLUSIONS: The City-BiTS-S presents appropriate psychometric properties to measure symptoms of PP-PTSD. Nevertheless, further research is recommended to confirm its validity in a clinical population and in different medical approaches to the birth process

Efectos del Kinesiotape en el dolor de rodilla y funcionalidad en sujetos con síndrome de dolor patelofemoral. Una revisión de la literatura

69 p.El síndrome de dolor patelofemoral (SDPF), es una patología que aqueja a un gran porcentaje de la población, más aún a la población femenina. Se han determinado un gran número de tratamientos, donde se destaca el uso del kinesiotape (KT), sin embargo, se desconoce cuál es su real efecto sobre dolor y la funcionalidad al utilizase en un plan de rehabilitación. El objetivo de este estudio es revisar el efecto de la aplicación del KT en la funcionalidad y dolor en sujetos con SPDF. Se realizó una búsqueda en las bases de datos PUBMED, SCOPUS, PEDro de los últimos 10 años utilizando los términos de búsqueda patelofemoral pain síndrome, athletic tape, genu valgum, pain. La selección de los estudios incluía a participantes de ambos sexos, que fueran intervenidos con KT y que los estudios fueran experimentales y cuasiexperimentales. La extracción de los datos se realizó a los estudios seleccionados que cumplieran con los criterios de inclusión, se les aplico la escala PEDro y se tabularon analizándose el dolor, la funcionalidad de miembro inferior (MMII) y la técnica de KT empleada. Se incluyeron 12 artículos con 410 pacientes en total, de los cuales 7 artículos obtuvieron una disminución de dolor, 4 artículos obtuvieron un aumento en la funcionalidad de MMII. Se utilizaron técnicas musculares de KT donde 7 artículos realizaron la colocación en el vasto medial oblicuo (VMO). Se concluye que la aplicación de KT con una técnica muscular en el VMO es capaz de disminuir el dolor, mientras que en cuanto a la funcionalidad no es del todo claro

Effect of the carbon nanotube surface characteristics on the conductivity and dielectric constant of carbon nanotube/poly(vinylidene fluoride) composites

Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal. The obtained samples were characterized by adsorption of N2 at -196°C, temperature-programmed desorption and determination of pH at the point of zero charge. CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%. It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response