837 research outputs found

    A cerebral bridge from olfactory cognition to spatial navigation

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    An evolutionary paradox is the variability of the olfactory bulb size, in contrast to the other brain regions, which are sized proportionally to the peripheral function. This variability seems to be the result of selection for the olfactory function. This disagreement may derive from considering smell as a sense linked to odorous discrimination. In many vertebrates and in terrestrial and marine mammals, the sense of smell has evolved into functions related to the eco-localization. So, if the olfactory function involves spatial perception and navigation, this, couldexplain the proportional discrepancy between the olfactory bulb and olfactory cortex. Humans are able to discriminate a spatial position as a function of olfactory cues. Vice versa, in neurodegenerative syndromes the orientation capacity and olfactory perception are impaired. This leads us to think that could be a common cross-modal processing, of phylogenetic origin, which links olfactory perception and spatial orientation. Starting from these theoretical assumptions, we conducted a basic research, on 100 healthy subjects, investigating, through both behavioral and electroencephalographic data, the connection between spatial memory span and olfactory spatial memory span. Subjects were assessed through a three-condition task: normal Corsi Block Test (CBT), ‘Olfactory’ Block Test (OBT) and a ‘Semantic-Olfactory’ Block Test (SOBT). CBT consisted in a test on spatial memory span; OBT consisted in a presentation a spatial sequences of 9 different odorants (i.e., Eucalyptol, Carvone, Eugenol, Isoamyl Acetate, Geraniol, Phenethyl Alcohol, Acetophenone, Cinnamon, Hexanal) instilled on paper square not recognizable by any sign, positioned on a CBT, and showed in a spatial navigation way, and SOBT consisted of a semantic labelled of olfactory spatial navigation. A GLM repeated measure highlighted significant differences during the three conditions. Subjects had different SPANs due to different conditions. The Semantic olfactory memory SPAN was inferior respect Olfactory span and Spatial Span. Furthermore was found a significant positive correlation between the three condition. The 5 subjects with higher SPAN scores, 5 with medium scores and the 5 subjects with lower SPAN scores were recruited to investigate ERP components elicited during the cross-modal task. Subjects had to perform, during a high-density EEG recording, an olfactory task (administered through the device US2017127971 (A1) “? 2017-05-11), an EEG Posner spatial cueing task and a go/no-go olfactory semantic categorization task. The results of this study will be discussed in light of a theoretical connection between these three aspects of cortical functions that seem strongly interconnected

    miR-29b and miR-198 overexpression in CD8<sup>+</sup> T cells of renal cell carcinoma patients down-modulates JAK3 and MCL-1 leading to immune dysfunction

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    Background: Mammalian microRNAs (miR) regulate the expression of genes relevant for the development of adaptive and innate immunity against cancer. Since T cell dysfunction has previously been reported in patients with renal cell carcinoma (RCC; clear cell type), we aimed to analyze these immune cells for genetic and protein differences when compared to normal donor T cells freshly after isolation and 35 days after in vitro stimulation (IVS) with HLA-matched RCC tumor cells. Methods: We investigated gene expression profiles of tumor-reactive CD8+ T cells obtained from RCC patient and compared with their HLA-matched healthy sibling donors using a microarray approach. In addition, miRNAs analysis was performed in a validation cohort of peripheral blood CD8+ T cells from 25 RCC patients compared to 15 healthy volunteers. Results: We observed that CD8+ T cells from RCC patients expressed reduced levels of anti-apoptotic and proliferation-associated gene products when compared with normal donor T cells both pre- and post-IVS. In particular, JAK3 and MCL-1 were down-regulated in patient CD8+ T cells versus their normal counterparts, likely due to defective suppressor activity of miR-29b and miR-198 in RCC CD8+ T cells. Indeed, specific inhibition of miR-29b or miR-198 in peripheral blood mononuclear cells (PBMCs) isolated from RCC patients, resulted in the up-regulation of JAK3 and MCL-1 proteins and significant improvement of cell survival in vitro. Conclusions: Our results suggest that miR-29b and miR-198 dysregulation in RCC patient CD8+ T cells is associated with dysfunctional immunity and foreshadow the development of miR-targeted therapeutics to correct such T cell defects in vivo

    MA-XRF measurement for corrosion assessment on bronze artefacts

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    In this study, an innovative portable macro X-Ray Fluorescence (MA-XRF) scanner prototype has been employed in order to gain information on composition and distribution of corrosion products artificially grown on Cu-based coupons. First results have shown the importance of using artificially corroded reference samples before any assessment on archaeological artefacts. Moreover, the prototype used demonstrated to be a powerful tool for understanding complex corrosion processes which might occur on Cu-based alloys. The scanner was able to detect light elements as S and Cl, essential for studying the distribution of specific corrosion compounds. Using imaging techniques, it was possible to observe a gradient in Cu elemental maps intensity caused by the overlapping of a thicker corrosion product layer

    MA-XRF measurement for corrosion assessment on bronze artefacts

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    In this study, an innovative portable macro X-Ray Fluorescence (MA-XRF) scanner prototype has been employed in order to gain information on composition and distribution of corrosion products artificially grown on Cu-based coupons. First results have shown the importance of using artificially corroded reference samples before any assessment on archaeological artefacts. Moreover, the prototype used demonstrated to be a powerful tool for understanding complex corrosion processes which might occur on Cu-based alloys. The scanner was able to detect light elements as S and Cl, essential for studying the distribution of specific corrosion compounds. Using imaging techniques, it was possible to observe a gradient in Cu elemental maps intensity caused by the overlapping of a thicker corrosion product layer

    CD40 cross-linking induces migration of renal tumor cell through nuclear factor of activated T cells (NFAT) activation

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    CD40 crosslinking plays an important role in regulating cell migration, adhesion and proliferation in renal cell carcinoma (RCC). CD40/CD40L interaction on RCC cells activates different intracellular pathways but the molecular mechanisms leading to cell scattering are not yet clearly defined. Aim of our study was to investigate the main intracellular pathways activated by CD40 ligation and their specific involvement in RCC cell migration. CD40 ligation increased the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH (2)-terminal kinase (JNK) and p38 MAPK. Furthermore, CD40 crosslinking activated different transcriptional factors on RCC cell lines: AP-1, NFkB and some members of the Nuclear Factor of Activated T cells (NFAT) family. Interestingly, the specific inhibition of NFAT factors by cyclosporine A, completely blocked RCC cell motility induced by CD40 ligation. In tumor tissue, we observed a higher expression of NFAT factors and in particular an increased activation and nuclear migration of NFATc4 on RCC tumor tissues belonging to patients that developed metastases when compared to those who did not. Moreover, CD40-CD40L interaction induced a cytoskeleton reorganization and increased the expression of integrin β1 on RCC cell lines, and this effect was reversed by cyclosporine A and NFAT inhibition. These data suggest that CD40 ligation induces the activation of different intracellular signaling pathways, in particular the NFATs factors, that could represent a potential therapeutic target in the setting of patients with metastatic RCC

    Age-related changes of elastic fibers in shoulder capsule of patients with glenohumeral instability: A pilot study

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    Background. Recurrent shoulder dislocations occur much more frequently in adolescents than in the older population but a clear explanation of this incidence does not exist. The aim of the present study was to define the age-related distribution of the elastic fibers (EFs) in the shoulder capsule's extracellular matrix as a factor influencing shoulder instability. Materials and Methods. Biopsy specimens were obtained from the shoulder capsule of patients divided preoperatively into three groups: Group 1 consisted of 10 male patients undergoing surgery for unidirectional traumatic anterior instability (TUBS); Group 2 consisted of 10 male patients undergoing surgery for multidirectional instability (MDI); Group 3 represents the control, including 10 patients with no history of instability. In addition to the group as a whole, specific subgroups were analyzed separately on the basis of the age of subjects: > 22 or < to 22 years. All the samples were analyzed by histochemical (Weigert's resorcinol fuchsin and Verhoeff's iron hematoxylin), immunohistochemical (monoclonal antielastin antibody), and histomorphometric methods. Results. Both the elastin density and the percentage of area covered by EFs were significantly higher in younger subjects (<22 years old). Furthermore, the elastin density and the percentage of area covered by EFs were significantly higher in specimens of group of patients affected by multidirectional shoulder instability in comparison to the other two groups. Conclusion. Data of the present study confirmed the presence of an age-related distribution of EFs in the human shoulder capsule. The greater amount of EFs observed in younger subjects and in unstable shoulders could play an important role in predisposing the joint to first dislocation and recurrence

    Age-related changes of elastic fibers in shoulder capsule of patients with glenohumeral instability: A pilot study

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    Background. Recurrent shoulder dislocations occur much more frequently in adolescents than in the older population but a clear explanation of this incidence does not exist. The aim of the present study was to define the age-related distribution of the elastic fibers (EFs) in the shoulder capsule's extracellular matrix as a factor influencing shoulder instability. Materials and Methods. Biopsy specimens were obtained from the shoulder capsule of patients divided preoperatively into three groups: Group 1 consisted of 10 male patients undergoing surgery for unidirectional traumatic anterior instability (TUBS); Group 2 consisted of 10 male patients undergoing surgery for multidirectional instability (MDI); Group 3 represents the control, including 10 patients with no history of instability. In addition to the group as a whole, specific subgroups were analyzed separately on the basis of the age of subjects: &gt; 22 or &lt; to 22 years. All the samples were analyzed by histochemical (Weigert's resorcinol fuchsin and Verhoeff's iron hematoxylin), immunohistochemical (monoclonal antielastin antibody), and histomorphometric methods. Results. Both the elastin density and the percentage of area covered by EFs were significantly higher in younger subjects (&lt;22 years old). Furthermore, the elastin density and the percentage of area covered by EFs were significantly higher in specimens of group of patients affected by multidirectional shoulder instability in comparison to the other two groups. Conclusion. Data of the present study confirmed the presence of an age-related distribution of EFs in the human shoulder capsule. The greater amount of EFs observed in younger subjects and in unstable shoulders could play an important role in predisposing the joint to first dislocation and recurrence

    Tomografia por impedância elétrica e seus possíveis usos na agropecuária.

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