957 resultados para SPORADIC MENINGIOMAS


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Introducción: El cáncer colorrectal es una patología con alto impacto en la salud pública, debido a su prevalencia, incidencia, severidad, costo e impacto en la salud mental y física del individuo y la familia. Ensayos clínicos realizados en pacientes con antecedente de infarto al miocardio que consumían ácido acetil salicílico (asa), calcio con y sin vitamina D, mostraron asociación entre el consumo de estos medicamentos y disminución en la incidencia en cáncer colorrectal y pólipos adenomatosos. Objetivo: Evaluar la literatura sobre el uso de asa, calcio con y sin vitamina D con relación a su impacto en la prevención del cáncer colorrectal y pólipos adenomatosos. Métodos: Se realizó revisión sistemática buscando ensayos clínicos realizados en pacientes con factores de riesgo para cáncer colorrectal y pólipos adenomatosos que usaron asa, calcio con y sin vitamina D fueron incluidos. Resultados: se escogieron 105 para la revisión sistemática. Conclusiones: Es necesario desarrollar más estudios que lleven a evaluar el efecto protector de la aspirina, calcio y vitamina D. En los artículos revisados la aspirina a dosis de 81 a 325 mg día se correlaciona con reducción de riesgo de aparición de CRC aunque la dosis ideal, el tiempo de inicio y la duración de la ingesta continua no son claros. Hacen falta estudios que comparen poblaciones con ingesta de asa a diferentes dosis.

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La enfermedad de Alzheimer (EA) es la demencia más frecuente y su prevalencia continúa en aumento tanto en Colombia como en el mundo. Esta investigación tuvo como objetivo explorar si las actitudes hacia la EA varían según la edad y género de 450 personas adultas colombianas. Se realizó un estudio exploratorio de corte transversal en el que se aplicó un cuestionario autodiligenciado. Se encontró que efectivamente hay algunas diferencias según la edad y el género en el componente cognoscitivo (creencias y conocimiento) y conductual (intención conductual y conducta) de las actitudes; y diferencias según el género en el componente afectivo. Se concluye que los conocimientos sobre la EA son escasos, que la tristeza es la emoción predominante hacia la EA y que es un tema de interés en el que predomina la idea de que afecta especialmente la memoria. Se discutieron los resultados reconociendo que esta es una aproximación inicial a las actitudes hacia la EA.

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Despite elevated incidence and recurrence rates for Primary Spontaneous Pneumothorax (PSP), little is known about its etiology, and the genetics of idiopathic PSP remains unexplored. To identify genetic variants contributing to sporadic PSP risk, we conducted the first PSP genome-wide association study. Two replicate pools of 92 Portuguese PSP cases and of 129 age- and sex-matched controls were allelotyped in triplicate on the Affymetrix Human SNP Array 6.0 arrays. Markers passing quality control were ranked by relative allele score difference between cases and controls (|RASdiff|), by a novel cluster method and by a combined Z-test. 101 single nucleotide polymorphisms (SNPs) were selected using these three approaches for technical validation by individual genotyping in the discovery dataset. 87 out of 94 successfully tested SNPs were nominally associated in the discovery dataset. Replication of the 87 technically validated SNPs was then carried out in an independent replication dataset of 100 Portuguese cases and 425 controls. The intergenic rs4733649 SNP in chromosome 8 (between LINC00824 and LINC00977) was associated with PSP in the discovery (P = 4.07E-03, ORC[95% CI] = 1.88[1.22–2.89]), replication (P = 1.50E-02, ORC[95% CI] = 1.50[1.08–2.09]) and combined datasets (P = 8.61E-05, ORC[95% CI] = 1.65[1.29–2.13]). This study identified for the first time one genetic risk factor for sporadic PSP, but future studies are warranted to further confirm this finding in other populations and uncover its functional role in PSP pathogenesis.

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Geophysical surveying and geoelectricalmethods are effective to study permafrost distribution and conditions in polar environments. Geoelectrical methods are particularly suited to study the spatial distribution of permafrost because of its high electrical resistivity in comparison with that of soil or rock above 0 °C. In the South Shetland Islands permafrost is considered to be discontinuous up to elevations of 20–40ma.s.l., changing to continuous at higher altitudes. There are no specific data about the distribution of permafrost in Byers Peninsula, in Livingston Island, which is the largest ice-free area in the South Shetland Islands. With the purpose of better understanding the occurrence of permanent frozen conditions in this area, a geophysical survey using an electrical resistivity tomography (ERT)methodologywas conducted during the January 2015 field season, combined with geomorphological and ecological studies. Three overlapping electrical resistivity tomographies of 78meach were done along the same profile which ran from the coast to the highest raised beaches. The three electrical resistivity tomographies are combined in an electrical resistivitymodel which represents the distribution of the electrical resistivity of the ground to depths of about 13malong 158m. Several patches of high electrical resistivity were found, and interpreted as patches of sporadic permafrost. The lower limits of sporadic to discontinuous permafrost in the area are confirmed by the presence of permafrost-related landforms nearby. There is a close correspondence between moss patches and permafrost patches along the geoelectrical transect.

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The first study was designed to assess whether the involvement of the peripheral nervous system (PNS) belongs to the phenotypic spectrum of sporadic Creutzfeldt-Jakob disease (sCJD). To this aim, we reviewed medical records of 117 sCJDVV2, 65 sCJDMV2K, and 121 sCJDMM(V)1 subjects for symptoms/signs and neurophysiological data. We looked for the presence of PrPSc in postmortem PNS samples from 14 subjects by western blotting and real-time quaking-induced conversion (RT-QuIC) assay. Seventy-five (41.2%) VV2-MV2K patients, but only 11 (9.1%) MM(V)1, had symptoms/signs suggestive of PNS involvement and neuropathy was documented in half of the VV2-MV2K patients tested. RT-QuIC was positive in all PNS samples, whereas western blotting detected PrPSc in the sciatic nerve in only one VV2 and one MV2K. These results support the conclusion that peripheral neuropathy, likely related to PrPSc deposition, belongs to the phenotypic spectrum of sCJDMV2K and VV2, the two variants linked to the V2 strain. The second study aimed to characterize the genetic/molecular determinants of phenotypic variability in genetic CJD (gCJD). To this purpose, we compared 157 cases of gCJD to 300 of sCJD. We analyzed: demographic aspects, neurological symptoms/signs, histopathologic features and biochemical characteristics of PrPSc. The results strongly indicated that the clinicopathological phenotypes of gCJD largely overlap with those of sCJD and that the genotype at codon 129 in cis with the mutation (i.e. haplotype) contributes more than the latter to the disease phenotype. Some mutations, however, cause phenotypic variations including haplotype-specific patterns of PrPSc deposition such as the “dense” synaptic pattern (E200K-129M), the intraneuronal dots (E200K-129V), and the linear stripes perpendicular to the surface in the molecular layer of cerebellum (OPRIs-129M). Overall, these results suggest that in gCJD PRNP mutations do not cause the emergence of novel prion strains, but rather confer increased susceptibility to the disease in conjunction with “minor” clinicopathological variations.

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Proton radiation therapy is a form of external radiation that uses charged particles which have distinct physical advantages to deliver the majority of its dose in the target while minimizing the dose of radiation to normal tissues. In children who are particularly susceptible even at low and medium doses of radiation, the significant reduction of integral dose can potentially mitigate the incidence of side effects and improve quality of life. The aim of the first part of the thesis is to describe the physical and radiobiological properties of protons, the Proton Therapy Center of Trento (TCPT) active for clinical purpose since 2014, which use the most recent technique called active pencil beam scanning. The second part of the thesis describes the preliminary clinical results of 23 pediatric patients with central nervous system tumors as well as of two aggressive pediatric meningiomas treated with pencil beam scanning. All the patients were particularly well-suited candidates for proton therapy (PT) for possible benefits in terms of survival and incidence of acute and late side effects. We reported also a multicentric experience of 27 medulloblastoma patients (median age 6 years, M/F ratio 13/14) treated between 2015 and 2020 at TPTC coming from three Pediatric oncology centers: Bologna, Florence, and Ljubljana, with a focus on clinical results and toxicities related to radiotherapy (RT). Proton therapy was associated with mostly mild acute and late adverse effects and no cases of CNS necrosis or high grade of neuroradiological abnormailities. Comparable rates of survival and local control were obtained to those achievable with conventional RT. Finally, we performed a systematic review to specifically address the safety of PT for pediatric CNS patients, late side effects and clinical effectiveness after PT in this patient group.

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In this study, the duodenum, spleen, tongue, and lungs were sampled from 56 Italian wolves who died between 2017 and 2020. The aim of the study was to evaluate the presence and spread of DNA and RNA viruses in the wolf population examined, relating the virological results to: year of sampling, region of origin, sex, age, season, genetic determination of the species, nutritional conditions, causes of death, matrices examined. In addition, the presence or absence of co-infections was evaluated. Through molecular methods, the presence of genomic DNA of three important DNA viruses was investigated, i.e.: Canine Parvovirus type 2 (CPV-2), Canine Adenovirus type 1 (CAdV-1), Canine Adenovirus type 2 (CAdV-2). Furthermore, the presence of genomic RNA of the important RNA viruses, Canine Enteric Coronavirus (CCoV) and Canine Distemper Virus (CDV), was also investigated. The results showed that the virus with the highest prevalence in the wolf population studied was CPV-2, found in 78.6% of subjects (44/56). The prevalence of CAdV was 17.9% (10/56), in particular CAdV-1 (12.5% - 7/56) and CAdV-2 (5.4% - 3/56). The results of the molecular investigations in RT-PCR of the two RNA viruses (CCoV and CDV) did not give positive results in the study population. In this study it was observed that the majority of wolves that resulted positive were in good nutritional conditions, thus excluding a direct cause of death from CPV-2, CAdV-1, and CAdV- 2 infections. Moreover, the prevalence obtained in this study suggests that, during the years here studied, the circulation of CAdV-1 and CAdV-2 in Italian wolves of the three sampled regions was sporadic, proving consistent with sporadic and short-lived introductions of the virus in these populations. However, the situation for CPV-2 is different as there was a circulation that suggests a pattern of continuous and lasting endemic exposure over time.

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Gastrointestinal stromal tumors (GIST) are the most common di tumors of the gastrointestinal tract, arising from the interstitial cells of Cajal (ICCs) or their precursors. The vast majority of GISTs (75–85% of GIST) harbor KIT or PDGFRA mutations. A small percentage of GIST (about 10‐15%) do not harbor any of these driver mutations and have historically been called wild-type (WT). Among them, from 20% to 40% show loss of function of the succinate dehydrogenase complex (SDH), also defined as SDH‐deficient GIST. SDH-deficient GISTs display distinctive clinical and pathological features, and can be sporadic or associated with Carney triad or Carney-Stratakis syndrome. These tumors arise most frequently in the stomach with predilection to distal stomach and antrum, have a multi-nodular growth, display a histological epithelioid phenotype, and present frequent lympho-vascular invasion. Occurrence of lymph node metastases and indolent course are representative features of SDH-deficient GISTs. This subset of GIST is known for the immunohistochemical loss of succinate dehydrogenase subunit B (SDHB), which signals the loss of function of the entire SDH-complex. The overall aim of my PhD project consists of the comprehensive characterization of SDH deficient GIST. Throughout the project, clinical, molecular and cellular characterizations were performed using next-generation sequencing technologies (NGS), that has the potential to allow the identification of molecular patterns useful for the diagnosis and development of novel treatments. Moreover, while there are many different cell lines and preclinical models of KIT/PDGFRA mutant GIST, no reliable cell model of SDH-deficient GIST has currently been developed, which could be used for studies on tumor evolution and in vitro assessments of drug response. Therefore, another aim of this project was to develop a pre-clinical model of SDH deficient GIST using the novel technology of induced pluripotent stem cells (iPSC).

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Alzheimer’s disease (AD) is a chronic, progressive neurodegenerative disease, characterized by the impairment of mnesic and cognitive functions, that represents the most frequent type of dementia in older people worldwide. Aging is the most important risk factor for the sporadic form of the pathology and it is associated to the progressive impairment of the proteostasis network. The endoplasmic reticulum (ER), the main cellular actor involved in proteostasis, appears significantly compromised in AD due to the accumulation of β-amyloid (Aβ) protein and phosphorylated-tau protein. Increasing proteins misfolding activates a specific cellular response known as Unfolded Protein response (UPR) which orchestrates the recovery of ER function. The aim of the present study was to investigate the role of UPR and aging process in a murine model of AD induced by intracerebroventricular (i.c.v.) injection of Aβ1-42 oligomers at 3 or 18 months. The oligomers injection in aged animals caused the increased of memory impairment, oxidative stress, and the depletion of glutathione reserve. Furthermore, the RNA-sequencing analysis was performed and the bioinformatic analysis showed the enrichment of several pathways involved in neurodegeneration and protein regulations. The following analysis highlighted the significant dysregulation of the three branches of the UPR, the protein kinase RNA-like ER kinase (PERK), inositol-requiring protein 1α (IRE1α) and activating transcription factor 6 (ATF-6). In turn, ER stress affected the PI3K/Akt/Gsk3β and MAPK/ERK pathways, highlighting Mapkapk5 as a potential marker of the neurodegenerative process, which regulation could lead to the definition of new pharmacological and neuroprotective strategies to counteract AD.

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Contaminants of emerging concern are increasingly detected in the water cycle, with endocrine-disrupting chemicals (EDCs) receiving attention due to their potential to cause adverse health effects even at low concentrations. Although the EU has recently introduced some EDCs into drinking water legislation, most drinking water treatment plants (DWTPs) are not designed to remove EDCs, making their detection and removal in DWTPs an important challenge. The aim of this doctoral project was to investigate hormones and phenolic compounds as suspected EDCs in drinking waters across the Romagna area (Italy). The main objectives were to assess the occurrence of considered contaminants in source and drinking water from three DWTPs, characterize the effectiveness of removal by different water treatment processes, and evaluate the potential biological impact on drinking water and human health. Specifically, a complementary approach of target chemical analysis and effect-based methods was adopted to explore drinking water quality, treatment efficacy, and biological potential. This study found that nonylphenol (NP) was prevalent in all samples, followed by BPA. Sporadic contamination of hormones was found only in source waters. Although the measured EDC concentrations in drinking water did not exceed threshold guideline values, the potential role of DWTPs as an additional source of EDC contamination should be considered. Significant increases in BPA and NP levels were observed during water treatment steps, which were also reflected in estrogenic and mutagenic responses in water samples after the ultrafiltration. This highlights the need to monitor water quality during various treatment processes to improve the efficiency of DWTPs. Biological assessments on finished water did not reveal any bioactivity, except for few treated water samples that exhibited estrogenic responses. Overall, the data emphasize the high quality of produced drinking water and the value of applying integrated chemical analysis and in vitro bioassays for water quality assessment.

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The research originates in the necessity to bring a new systematic archaeological perspective to the prehistoric background of northern Apulia. Therefore, the aim of the R.P.C.M. Apulia project is to shed new light on a specific chronological arch, from the Neolithic to Early Bronze Age, of the northern part of the Apulia, because the related studies resulted updated to the 70-80’s with some sporadic exception. Moreover, addressing the investigation to the relationship between the communities and the landscape, so how they could exploit the lands and how they could move into this area keeping in touch. To reconstruct the Prehistorical dynamics, it has been necessary first of all to create a database containing all the information about the sites thus to validate them and classifying them according to a model specifically built. The storing operation has been conducted with the software ArcGIS v.10.1 and the sites have been georeferenced on the map as points. It provided the basis on which developing the analysis concerning the mobility (Least Cost Path) and landscape perception (Fuzzy Viewshed Analysis). The first one has been considered to evaluate the mobility into the study area. Therefore, to generate sample paths on the base of the time in reaching a specific point and the terrain trend. The gained information has been collected to hypothesize how they could keep in touch across the chronological changes for purposes related to trading/idea/people exchanges. The visibility analysis has been led to grasp how the groups perceived the landscape through the sight. This datum covered an important role, especially from the Copper Age, concerning the domain and control of the trading ways. The data coming from the mentioned analysis have been used to read into the settlement choices according to the development of the new socio-economic relationships and plan survey activity.

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Pervasive and distributed Internet of Things (IoT) devices demand ubiquitous coverage beyond No-man’s land. To satisfy plethora of IoT devices with resilient connectivity, Non-Terrestrial Networks (NTN) will be pivotal to assist and complement terrestrial systems. In a massiveMTC scenario over NTN, characterized by sporadic uplink data reports, all the terminals within a satellite beam shall be served during the short visibility window of the flying platform, thus generating congestion due to simultaneous access attempts of IoT devices on the same radio resource. The more terminals collide, the more average-time it takes to complete an access which is due to the decreased number of successful attempts caused by Back-off commands of legacy methods. A possible countermeasure is represented by Non-Orthogonal Multiple Access scheme, which requires the knowledge of the number of superimposed NPRACH preambles. This work addresses this problem by proposing a Neural Network (NN) algorithm to cope with the uncoordinated random access performed by a prodigious number of Narrowband-IoT devices. Our proposed method classifies the number of colliding users, and for each estimates the Time of Arrival (ToA). The performance assessment, under Line of Sight (LoS) and Non-LoS conditions in sub-urban environments with two different satellite configurations, shows significant benefits of the proposed NN algorithm with respect to traditional methods for the ToA estimation.