This paper introduces a novel device based on a tactile interface to replace the attendant joystick in electric wheelchairs. It can also be used in other vehicles such as shopping trolleys. Its use ...allows intuitive driving that requires little or no training, so its usability is high. This is achieved by a tactile sensor located on the handlebar of the chair or trolley and the processing of the information provided by it. When the user interacts with the handle of the chair or trolley, he or she exerts a pressure pattern that depends on the intention to accelerate, brake or turn to the left or right. The electronics within the device then perform the signal conditioning and processing of the information received, identifying the intention of the user on the basis of this pattern using an algorithm, and translating it into control signals for the control module of the wheelchair. These signals are equivalent to those provided by a joystick. This proposal aims to help disabled people and their attendees and prolong the personal autonomy in a context of aging populations.
Osteoporosis is characterized by the loss of bone mass, deterioration of the bone microarchitecture, and an increased risk of fractures; these later complications are associated with significant ...morbidity and mortality. The asymptomatic and progressive nature of osteoporosis underscores the importance of identifying this entity in early stages. Despite the various treatments available, the prevention of the disease represents the most important aspect of management. An adequate intake of calcium and vitamin D as well as a healthy lifestyle is the basis for maintaining bone health. When osteoporosis is diagnosed, the choice of medications must be individualized considering characteristics of the patient and the risk of fractures. In this article, we review the main causes of osteoporosis, when and how to start treatment, and appropriate therapy and monitoring.
This paper shows realizations of a piezoresistive tactile sensor with a low cost screen-printing technology. A few samples were fabricated for different materials used as insulator between the ...conductive layers and as top layer or cover. Both can be used to tune the sensitivity of the sensor. However, a large influence is also observed of the roughness at the contact interface on the sensitivity and linearity of the output, as well as on mismatching between the outputs from different taxels. The roughness at the contact interface is behind the transduction principle of the sensor, but it also limits its performance if the wavelength of the roughness is comparable or even longer than the size of the contacts. The paper shows experimental results that confirm this relationship and discusses its consequences in sensor response related to the materials chosen for the insulator and the cover. Moreover, simulations with FEA tools and with simple models are used to support the discussions and conclusions obtained from the experimental data. This provides insights into the sensor behaviour that are shared by other sensors based on the same principle.
Interleukin-18 (IL-18, interferon IFN-gamma-inducing factor) is a proinflammatory cytokine converted to a biologically active molecule by interleukin (IL)-1beta converting enzyme (caspase-1). A wide ...range of normal and cancer cell types can produce and respond to IL-18 through a specific receptor (IL-18R) belonging to the toll-like receptor family. The activity of IL-18 is regulated by IL-18-binding protein (IL-18bp), a secreted protein possessing the ability to neutralize IL-18 and whose blood level is affected by renal function and is induced by IFNgamma. IL-18 plays a central role in inflammation and immune response, contributing to the pathogenesis and pathophysiology of infectious and inflammatory diseases. Because immune-stimulating effects of IL-18 have antineoplastic properties, IL-18 has been proposed as a novel adjuvant therapy against cancer. However, IL-18 increases in the blood of the majority of cancer patients and has been associated with disease progression and, in some cancer types, with metastatic recurrence risk and poor clinical outcome and survival. Under experimental conditions, cancer cells can also escape immune recognition, increase their adherence to the microvascular wall and even induce production of angiogenic and tumor growth-stimulating factors via IL-18-dependent mechanism. This is particularly visible in melanoma cells. Thus, the role of IL-18 in cancer progression and metastasis remains controversial. This review examines the clinical correlations and biological effects of IL-18 during cancer development and highlights recent experimental insights into prometastatic and proangiogenic effects of IL-18 and the use of IL-18bp against cancer progression.
There is no systematic knowledge about how individuals with Locked-in Syndrome (LIS) experience their situation. A phenomenology of LIS, in the sense of a description of subjective experience as ...lived by the ill persons themselves, does not yet exist as an organized endeavor. The present article takes a step in that direction by reviewing various materials and making some suggestions. First-person narratives provide the most important sources, but very few have been discussed. LIS barely appears in bioethics and neuroethics. Research on Quality of Life (QOL) provides relevant information, one questionnaire study explores the sense of personal continuity in LIS patients, and LIS has been used as a test case of theories in “embodied cognition” and to explore issues in the phenomenology of illness and communication. A systematic phenomenology of LIS would draw on these different areas: while some deal directly with subjective experience, others throw light on its psychological, sociocultural and materials conditions. Such an undertaking can contribute to the improvement of care and QOL, and help inform philosophical questions, such as those concerning the properties that define persons, the conditions of their identity and continuity, or the dynamics of embodiment and intersubjectivity.
Tactile sensors suffer from many types of interference and errors like crosstalk, non-linearity, drift or hysteresis, therefore calibration should be carried out to compensate for these deviations. ...However, this procedure is difficult in sensors mounted on artificial hands for robots or prosthetics for instance, where the sensor usually bends to cover a curved surface. Moreover, the calibration procedure should be repeated often because the correction parameters are easily altered by time and surrounding conditions. Furthermore, this intensive and complex calibration could be less determinant, or at least simpler. This is because manipulation algorithms do not commonly use the whole data set from the tactile image, but only a few parameters such as the moments of the tactile image. These parameters could be changed less by common errors and interferences, or at least their variations could be in the order of those caused by accepted limitations, like reduced spatial resolution. This paper shows results from experiments to support this idea. The experiments are carried out with a high performance commercial sensor as well as with a low-cost error-prone sensor built with a common procedure in robotics.
Culture: by the brain and in the brain? Ortega, Francisco; Vidal, Fernando
História, ciências, saúde--Manguinhos,
10/2016, Volume:
23, Issue:
4
Journal Article
Peer reviewed
Open access
Since the 1990s, several disciplines have emerged at the interface between neuroscience and the social and human sciences. For the most part, they aim at capturing the commonalities that underlay the ...heterogeneity of human behaviors and experiences. Neuroanthropology and cultural neuroscience, or the "neurodisciplines of culture," appear different, since their goal is to understand specificity rather than commonality and to address how cultural differences are inscribed in the brain. After offering an overview of these disciplines, and of their relation to endeavors such as cultural psychology and social neuroscience, this article discusses some of the most representative studies in the area in order to explore in which ways they are relevant for an understanding of culture.
Implantation and growth of metastatic cancer cells at distant organs is promoted by inflammation-dependent mechanisms. A hepatic melanoma metastasis model where a majority of metastases are generated ...via interleukin-18-dependent mechanisms was used to test whether anti-inflammatory properties of resveratrol can interfere with mechanisms of metastasis.
Two experimental treatment schedules were used: 1) Mice received one daily oral dose of 1 mg/kg resveratrol after cancer cell injection and the metastasis number and volume were determined on day 12. 2) Mice received one daily oral dose of 1 mg/kg resveratrol along the 5 days prior to the injection of cancer cells and both interleukin-18 (IL-18) concentration in the hepatic blood and microvascular retention of luciferase-transfected B16M cells were determined on the 18th hour. In vitro, primary cultured hepatic sinusoidal endothelial cells were treated with B16M-conditioned medium to mimic their in vivo activation by tumor-derived factors and the effect of resveratrol on IL-18 secretion, on vascular cell adhesion molecule-1 (VCAM-1) expression and on tumor cell adhesion were studied. The effect of resveratrol on melanoma cell activation by IL-18 was also studied.
Resveratrol remarkably inhibited hepatic retention and metastatic growth of melanoma cells by 50% and 75%, respectively. The mechanism involved IL-18 blockade at three levels: First, resveratrol prevented IL-18 augmentation in the blood of melanoma cell-infiltrated livers. Second, resveratrol inhibited IL-18-dependent expression of VCAM-1 by tumor-activated hepatic sinusoidal endothelium, preventing melanoma cell adhesion to the microvasculature. Third, resveratrol inhibited adhesion- and proliferation-stimulating effects of IL-18 on metastatic melanoma cells through hydrogen peroxide-dependent nuclear factor-kappaB translocation blockade on these cells.
These results demonstrate multiple sites for therapeutic intervention using resveratrol within the prometastatic microenvironment generated by tumor-induced hepatic IL-18, and suggest a remarkable effect of resveratrol in the prevention of inflammation-dependent melanoma metastasis in the liver.
Studies of the normal skull anatomy of the Patagonian Huemul deer are scarce. Currently, the findings of bone lesions in the skull associated with metabolic imbalances are frequent in the literature. ...The objective of this study was to provide anatomical and morphometric data of the cranium and facies including a morphofunctional interpretation as a reference for clinical, ecomorphological and educational purposes. Five skulls were described, measured, scanned and digitally reconstructed. The presence of a caudal projection of the vomer bone, the absence of the facial tubercle and thin bones forming the cranial cavity were observed. Linear measurements allowed the skull to be classified as dolichocephalic, hyperlepten and ultra‐dolichocranial. In conclusion, the Patagonian Huemul has a long head, an extremely long skull and a very narrow face. The thickness of the bones that made up the walls of the cranial cavity suggests chronic metabolic imbalances in response to mineral deficiency. The anatomical and morphometric data obtained in this study strongly emphasizes the relevance of considering the implementation of such management policies that aim at promoting an optimal nutritional context.
The transdifferentiation of hepatic stellate cells (HSCs) into myofibroblasts is a major mechanism for stroma development in hepatic metastasis, but their regulatory pathways remain unclear. ...Transdifferentiated HSCs from fibrotic liver express high levels of the fibrillar collagen receptor discoidin domain receptor 2 (DDR2), but it is unclear if DDR2 plays a direct profibrogenic role in the tumour microenvironment.
To assess the impact of DDR2 on the prometastatic role of HSC-derived myofibroblasts.
Hepatic metastases were induced in DDR2(-/-) and DDR2(+/+) mice by intrasplenic injection of MCA38 colon carcinoma cells, and their growth and features were characterised. Stromagenic, angiogenic and cancer cell proliferation responses were quantified in metastases by immunohistochemistry. The adhesion-, migration- and proliferation-stimulating activities of supernatants from primary cultured DDR2(-/-) and DDR2(+/+) HSCs, incubated in MCA38 cell-conditioned medium, were evaluated in primary cultured liver sinusoidal endothelium cells (LSECs) and MCA38 cells. Gene expression signatures from freshly isolated DDR2(-/-) and DDR2(+/+) HSCs were compared and DDR2-regulated genes were studied by RT-PCR under basal conditions and after stimulation with MCA38 tumour-conditioned media.
Metastases were increased three fold in DDR2(-/-) livers, and contained a higher density of α-smooth muscle actin-expressing myofibroblasts, CD31-expressing microvessels and Ki67-expressing MCA38 cells than metastases in DDR2(+/+) livers. Media conditioned by MCA38-activated DDR2(-/-) HSCs significantly increased adhesion, migration and proliferation of LSECs and MCA38 cells, compared with DDR2(+/+) HSCs. DDR2 deficiency in HSCs led to decreased gene expression of interferon γ-inducing factor interleukin (IL)-18 and insulin-like growth factor-I; and increased gene expression of prometastatic factors IL-10, transforming growth factor (TGF)β and vascular endothelial growth factor (VEGF), bone morphogenetic protein-7 and syndecan-1. MC38 tumour-conditioned media further exacerbated expression changes in DDR2-dependent IL-10, TGFβ and VEGF genes.
DDR2 deficiency fosters the myofibroblast transdifferentiation of tumour-activated HSCs, generating a prometastatic microenvironment in the liver via HSC-derived factors. These findings underscore the role of stromal cells in conditioning the hepatic microenvironment for metastases through altered receptor-stroma interactions.
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