969 resultados para Morte celular
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The cerebral cortex of mammals is histologically organized into different layers of excitatory neurons that have distinct patterns of connections with cortical or subcortical targets. During development, these cortical layers are established through an intricate combination of neuronal specification and migration in a radial pattern known as "insideout": deep-layer neurons are generated prior to upper-layer neurons. In the last few decades, several genes encoding transcription factors involved in the sequential specification of neurons destined to different cortical layers have been identified. However, the influence of early-generated neurons in the specification of subsequent neuronal cohorts remains unclear. To investigate this possible influence, we induced the selective death of cortical neurons from layer V and VI before the generation of layer II, III and IV neurons. Thus, we can evaluate the effects of ablation of early born neurons on the phenotype of late born neurons. Our data shows that one-day after ablation, layer VI neurons expressing the transcription factor TBR1 are newly generated while virtually no neuron expressing TBR1 was generated in the same age in control animals. This suggests that progenitors involved in the generation of neurons destined for superficial layers suffer interference from the selective death of neurons in deep layers, changing their specification. We also observed that while TBR1-positive neurons are located exclusively in deep cortical layers of control animals, many TBR1-positive neurons are misplaced in superficial layers of ablated animals, suggesting that the migration of cortical neurons could be controlled independently of neuronal phenotypes. Furthermore, we observed an increase in layer V neurons expressing CTIP2 and neurons expressing SATB2 and that these cells have changed their distributions. As a conclusion, our data indicate the existence of a mechanism of control exercised by the early-generated neurons in the cerebral cortex on the fate of the progenitors involved in the generation of the following cortical neurons. This mechanism could help to control the number of neurons in different layers and contribute to the establishment of different cortical areas
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Resposta celular Th1 /Th2 na doença periodontal experimental, em ratos: um estudo imuno-histoquímico
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Host response plays a major role in the pathogenesis of periodontal disease. Mediators such as inflammatory cytokines which are secreted during the immune response to bacterial challenges have ambiguous functions that may or may not lead to protection of the attacked tissue. In this context, experimental evidence suggests that T-helper 1 (Th-1) and T-helper 2 (Th-2) mediated responses are potentially important during the disease process. The aims of this study therefore were to further clarify the role played by Th2 cells during different time points of the active phase of periodontal disease, as well as, to investigate whether there was any evidence of a Th1 response in the periodontal disease microenvironment. Experimental periodontitis was induced in 30 Wistar male rats by placing cotton ligatures around the mandibular first molars. The rats were then randomly divided into two groups. Group1 (G1=15) and Group 2 (G2=15). In G1 the ligatures were maintained for 2 days, whereas in G2 the ligatures were left for 15 days, a time point that corresponds to the advanced stage of periodontal disease The contra-lateral teeth served as controls (no ligatures). Immunohistochemical investigation for the presence in gingival tissue of Th2 specific transcription factor (GATA3) and the subunit of the IFN-γ receptor was carried out after the disease induction period. Light microscopy analysis revealed a decrease in the expression of GATA-3 as bone loss progressed. On the other hand, although IFN-γ R1 was detected at an early stage of the active phase of disease its expression remained unaltered during the remaining period of the study. These results indicate that the Th2 response have a protective role during the pathogenesis of periodontal disease and that the progression of the periodontal disease is related with the unbalance of the responses Th1/Th2
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Oral squamous cell carcinoma (OSCC) is the most common malignancy in oral cavity and human papillomavirus (HPV) may have an important role in its development. The aim of this experiment was to investigate the HPV DNA and viral types in 90 cases of OSCC. Moreover, a comparative analysis between the cases of OSSC with and without HPV DNA was performed by using cell cycle markers p21 and pRb in order to detect a possible correlation of these proteins and HPV infection. DNA was extracted from paraffin embedded tissue and amplified by PCR (polymerase chain reaction) with primers PCO3+ e PCO4+ for a fragment of human β-globin gene. After this procedure, PCR for HPV DNA detection was realized using a pair of generic primers GP5+ e GP6+. Immunohistochemical study was performed by streptoavidin-biotin technique and antibodies against p21 and pRb proteins were employed. Eighty-eight cases were positive for human β-globin gene and HPV DNA was found in 26 (29.5%) of then. It could not be detected significant correlation between HPV and age, sex and anatomical sites of the lesion. The most prevalent viral type was HPV 18 (80.8%). Regarding the immunohistochemical analysis, it was detected significant association between HPV presence and pRb immunoexpression (p=0,044), nevertheless, the same was not observed in relation to p21 protein (p =0,416). It can be concluded that the low detection of HPV DNA in OSCC by the present experiment suggests a possible role of the virus in the development and progression in just a subset of this disease
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In rodents, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) are the main components of the circadian system. The SCN is considerate the site of an endogenous biological clock because can to generate rhythm and to synchronize to the environmental cues (zeitgebers) and IGL has been related as one of the main areas that modulate the action of SCN. Both receive projections of ganglion cells of retina and this projection to SCN is called retinohypothalamic tract (RHT). Moreover, the IGL is connected with SCN through of geniculohypothalamic tract (GHT). In primates (include humans) was not still demonstrated the presence of a homologous structure to the IGL. It is believed that the pregeniculate nucleus (PGN) can be the answer, but nothing it was still proven. Trying to answer that question, the objective of our study is to do a comparative analysis among PGN and IGL through of techniques immunohystochemicals, neural tracers and FOS expression after dark pulses. For this, we used as experimental model a primate of the new world, the common marmoset (Callithrix jacchus). Ours results may contribute to the elucidation of this lacuna in the circadian system once that the IGL is responsible for the transmission of nonphotic information to SCN and participate in the integration between photic and nonphotic stimulus to adjust the function of the SCN. In this way to find a same structure in primates represent an important achieve in the understanding of the biological rhythms in those animals
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The literature pointed that the way which people deal with death have been changing along centuries, and nowadays what is realized it is that, each time more, the human being have difficulties to deal with death. Due to the fact that the main function of the physician is to save their patients lives; responsibility that is aggravated by the necessity of to take decisions quickly, once he need to deal with the unexpected situations of the urgency and emergency, many times these professional have to face of impotency and fail situations, when he lose a patient. The main goal of this study was to understand the experience of physicians that work in the urgency and emergency, in front of death. These questioning it justified by the fact of the physicians do not have, many times, a space to express their suffering and anguish about the issues related to death in their work routine, despite lifedeath question to be often present their everyday. It is still possible to verify in the literature, an appointment of the necessity of to include in the curriculum of Medicine courses, subjects that approach such questions. The method used was based on the existential-phenomenological perspective, using as instrument the participant observation, to the intent of understand the routine in the urgency and emergency context, and semi-structured interview. It was interviewed six physicians that work in the urgency and emergency of the most important hospital of public health system of Natal-RN. The results showed that the physicians reported pleasure in work in the urgency and emergency, despite of they presented stress and the difficulties that they deal with in the public system. Despite of the fact that the death to be considered as a phenomenon that make part of the physician s routine, sometimes, deals with these one is more difficult. Many times losses generate an impotency and guilty feeling, as well as questionings about their performance during the attempts to save lives. We verified, from this study, the importance of the existence of some kind of intervention in the emergency, in order to the physicians can elaborate the questions about death and die emerged in their work. We consider yet that this study corroborates and reiterates the discussions concerning the importance of this thematic to be approached in a more effective way, during the academic formation of these professionals, as well as, the importance of a larger investment from the part of Government in the urgency and emergency sector, in order to propitiate to these professionals a work that brings less harmful for their health
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It is undeniable that all the extraordinary technological advances in contemporary society have increased the severe patients expectation and quality of life, especially cancer patients. On the other hand, it is easily verifiable by many researches that it was not possible to advance in the same proportion in caring for the human experience of death. Much is said about the anguish of a man facing death, of cancer patients in terminal stage, about their families, and very little about the feelings, anxieties and ways of coping with the medical professional who deals with this situation, specifically the clinical oncologist. Little is known about the experience of the doctor who has learned to take death as an enemy to be defeated, and increasingly is compelled to live at length with his advertisement. However, we started to watch in recent years a growing interest of researchers in this issue. This study seeks to add to this interest in order to understand the experience of clinical oncologists that accompany dying patients, the meanings they attach to death, ways of coping and the implications for providing care. This is a qualitative study in which was used as a tool for data collection an in-depth interview with the projective using script and scenes. Gadameriana Hermeneutics was used for analysis and interpretation of narratives. The subjects were 10 clinical oncologists who work at two institutions from cancer treatments in the state of Rio Grande do Norte, chosen from a variation in the time working in the specialty (minimum of one year, even old ones). However, you can bring some initial results for the dialogue. It was found that the death is still a topic that causes many difficulties in the daily lives of these professionals, the choice for oncology involves dealing with death without preparation in medical education; being close to the patient in the final moment, supporting the family, coping with own pain of loss and the inability to heal. These are central elements of the narratives. We also have investment in medical training and continuing education in setting up a demand that permeates the discourse of participants. Being able to listen to the subjective world of clinical oncologists will support the work not only for them as other professionals who deal with patients with advanced cancer, providing evidence to understand to what extent the meanings attributed to its know-how before patients on the verge of death interfere with the production of care and allow identify coping strategies in everyday life of these professionals that hinder or facilitate coping with death, promote or preclude the care with others and with themselves. It is hoped that research can contribute to the field of knowledge about the know-how in clinical oncology and their terminal-care-death oncologist-patient relationships, bringing runways capable of promoting a better quality of care in the production of all involved in this process: professionals, patients and families
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The present time is marked by the art of escape from death, which has become synonymous with failure, its exposure has become intolerable and the care of the dead body were assigned to third parties who market this practice through services and products that shape the market undertaker. In this context, in which death is an object of study, has arisen funeral officers, as professionals dealing with a dead body, with the pain of relatives and their reactions, often being the first to have contact with the death scene. As professionals in the health area, the morticians also deal with death. The first attempt to prevent the arrival of death, funeral officers already has begun their work routine from there. Death and its surrounding part of their profession. What about those professionals whose work demands as a feared and denied by society? This study aims to understand the intents, meanings and implications for the mortician to deal with death in their daily work in order to focus renewed attention to the care of these professionals. To this end, it was carried out a qualitative research grounded in the theoretical framework of Gadamerian hermeneutics for production and interpretation of narratives. It was used two methodological strategies for data collection: in-depth interview with script and workshop with the use of "scenes". Research participants were nine morticians funeral of two funeral agencies of the city of Natal. It was possible to detect the presence of the social imaginary of interdiction on the theme of death from living with feelings of his presence daily, from the need of respondents to naturalize their contacts with death, a requirement of their office to deal with the difficulties of manipulating body fluids and odors, sometimes in a state of decomposition; allied to wishes to achieve the goal of delivering to family-customers a "embellished" body for the final farewell. Being a mortician, in addition to not being a professional motivation, involves facing difficulties related to heavy routine work, low salaries, unprofitable work materials and equipments, besides having to deal with the social gaze that devalues the profession. In turn, they also deal with the pain coming especially from contact with family members, either when they are targets of these feelings of anger, whether they identify with the pain of the bereaved ones. On the other hand, when the recognition and gratitude of the families occur, they find meaning and beauty in their profession of caring for the dead body. The present study by giving voice to morticians has become possible to understand better their profession, the pain that surrounds and care needs of these workers. Finally, it has argued that the mortician may be recognized as a care professional for the way exercising caution with the dead body and their families.
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Death is a theme that fascinates, though at the same time, frightens and uneasy the human being, despite the finitude being present at our daily lives. In each historical time, death has been represented in a peculiar way, from familiar death (at Middle Ages), to interdicted death (at contemporary times). Through this path it‟s possible to recognize several attitudes and stages front of death and the process of dying as possibilities of coping and the understanding of these occurrences. In other hand, the palliative care proposal came as a humanized attention, front of the human finitude, recognizing death as a part of the vital cycle. The Brazilian reality, in this context, still faces a lot of political, economic and social barriers that makes difficult the consolidation of palliative care at the death process in the Brazilian Health Care policies. Currently, according to the Brazilian Palliative Care Association, Brazil presents an average of 40 services with this proposal. Such data portray our inexpressive condition in relation to these cares when considering the territorial extension and population of our country. Considering this scenario is relevant think about death and the process of dying at contemporary times, at a health context in which palliative care, when trying to humanize the process of dying, bring to light the issue of human finitude and the beingtowards- death, as thought by the philosopher Martin Heidegger. According to him, the human being (Dasein) is constituted as a being-towards-death, once death is its most own potentiality-for-bein and its last possibility to be lived. In view of the ideas presented, the proposed study appears as a qualitative research of existential-phenomenological inspiration and aims to understand the experience of being-toward-death from the psychological care to a person out of possibilities of cure living on palliative cares. The psychological care happened at the patient‟s home, understanding the clinical process of being-with-the-other from the written reports of the psychology/researcher, by the accompanying sessions, configured as an experience report. These reports are focused on the experiences lived by the patient, as well as apprehended by the psychologist at the intersubjectivity relation and its own experience with Dasein and, therefore, being-toward-death. The reports were hermeneutically interpreted, from the senses that emerged in this process, considering the notion of being-toward-death proposed by Heidegger. Furthermore, it was important to dialogue with other authors that approached the studied theme. It is perceived, through brief and meaningful reflections about the clinical treatments started, that the experience of illness with no possibilities of cure makes the Dasein revises feelings and experiences that were marked at the temporality and historicity of existence. It is a stage of life in which the cultural dimension and the common sense of finitude, often gains ground in the human condition, taken in its ordinary sense, unlike the way it has been thought from an ontological and existential perspective of death. Thus, there are singulars and revealing paths in the palliative care scenery as possible ways for authenticity of being-toward-death
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Enfoca-se aqui a vinculação íntima entre a exaustiva busca empreendida pelo espírito grego para edificar em terreno sólido as colossais fundações de uma ciência dos primeiros princípios, e o que supõe-se ser sua motivação secreta e última, a aspiração pela eternidade, o mais universal e genuíno desejo presente em todo ser humano, não ser obliterado pelo tempo.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Estudou-se retrospectivamente a evolução clínica de dois pacientes, até sua falência cardíaca irreversível (FCI), submetidos à monitorização contínua da pressão intracraniana (PIC). O estudo detalhado desses traçados mostrou que, nos dois casos a PIC atingiu valores máximos 5 e 12 h antes de ocorrer diminuição na amplitude das ondas, observada 47 e 60 h pré-FCI. Essa diminução foi progressiva e tornou-se linear cerca de 30 h antes da FCI, em ambos os casos. O diagnóstico clínico de morte encefálica (ME) foi obtido 3 e 28 hs após a linearidade do traçado. Os autores sugerem que o diagnóstico de ME pode ser definido mais precocemente com o uso da monitorização da PIC desde que o paciente não esteja sob sedação, e salientam a necessidade de mais observações, em número maior de pacientes.
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Apparent digestibility coefficient of dry matter, crude protein, ether extract, gross energy, of diets supplemented with spray dried whole yeast (1.0; 2.0 e 3.0%), autolyzed (1.0; 2.0 e 3.0%), yeast cell wall (0.1; 0.2 e 0.3%) plus a additional diet with no yeast and yeast derivatives were evaluated to Nile tilapia. Eighty juveniles (83.0+/-8.5g) were placed in eight 250L aquaria for feeding and four aquaria of the same volume for collecting faecal samples. Both sets were equipped with flow-trough recirculation system provided with mechanical and biological filter. Diets supplemented with whole yeast, autolyzed yeast, and yeast cell wall presented, as mean, superior apparent coefficient digestibility than control. It can be concluded that supplementation of yeast and yeast derivatives improve apparent coefficient digestibility of experimental diets and diets supplemented with estimated level of 2.13-2.36% autolyzed yeast shows better digestibility.
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INTRODUÇÃO: O reparo tissular é o objetivo final da cirurgia. A cultura celular requer arcabouço mecânico que dê suporte ao crescimento celular e difusão dos nutrientes. O uso do plasma rico em plaquetas (PRP) como um arcabouço 3D possui diversas vantagens: é material biológico, de fácil absorção pós-transplante, rico em fatores de crescimento, em especial PDGF- ββ e TGF-β que estimula síntese de matriz extracelular na cartilagem. OBJETIVO: Desenvolver arcabouço 3D à base de PRP. MATERIAIS E MÉTODOS: Duas formas foram idealizadas: Sphere e Carpet. Condições estéreis foram utilizadas. O gel de plaquetas permaneceu em cultura celular, observado diariamente em microscópio invertido. RESULTADOS: Ambos arcabouços obtiveram sucesso, com aspectos positivos e negativos. DISCUSSÃO: A forma Sphere não aderiu ao plástico. Observou-se retração do gel e investigação ao microscópio dificultada devido às áreas opacas no campo visual. A forma Carpet não aderiu ao plástico e apresentou-se translúcida. O tempo de estudo foi de 20 dias. CONCLUSÕES: A produção de um arcabouço 3D PRP foi um sucesso, e trata-se de uma alternativa que necessita ser mais utilizado e investigado para que se consolide em uma rota eficiente e confiável na tecnologia de engenharia tissular, particularmente em cultura de tecido cartilaginoso.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)