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1.
Nat Commun ; 15(1): 1876, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485924

RESUMO

Developing clinically predictive model systems for evaluating gene transfer and gene editing technologies has become increasingly important in the era of personalized medicine. Liver-directed gene therapies present a unique challenge due to the complexity of the human liver. In this work, we describe the application of whole human liver explants in an ex situ normothermic perfusion system to evaluate a set of fourteen natural and bioengineered adeno-associated viral (AAV) vectors directly in human liver, in the presence and absence of neutralizing human sera. Under non-neutralizing conditions, the recently developed AAV variants, AAV-SYD12 and AAV-LK03, emerged as the most functional variants in terms of cellular uptake and transgene expression. However, when assessed in the presence of human plasma containing anti-AAV neutralizing antibodies (NAbs), vectors of human origin, specifically those derived from AAV2/AAV3b, were extensively neutralized, whereas AAV8- derived variants performed efficiently. This study demonstrates the potential of using normothermic liver perfusion as a model for early-stage testing of liver-focused gene therapies. The results offer preliminary insights that could help inform the development of more effective translational strategies.


Assuntos
Dependovirus , Vetores Genéticos , Humanos , Vetores Genéticos/genética , Dependovirus/genética , Anticorpos Neutralizantes , Fígado , Perfusão
2.
Neuroscience ; 539: 66-75, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38220128

RESUMO

Current evidence suggests that glial cells provide C3 carbon sources to fuel neuronal activity; however, this notion has become challenged by biosensor studies carried out in acute brain slices or in vivo, showing that neuronal activity does not rely on the import of astrocyte-produced L-lactate. Rather, stimulated neurons become net lactate exporters, as it was also shown in Drosophila neurons, in which astrocyte-provided lactate returns as lipid droplets to be stored in glial cells. In this view, we investigate whether exogenously supplied monocarboxylates can support Drosophila motoneuron neurotransmitter release (NTR). By assessing the excitatory post-synaptic current (EPSC) amplitude under voltage-clamp as NTR indicative, we found that both pyruvate and L-lactate, as the only carbon sources in the synapses bathing-solution, cause a large transient NTR enhancement, which declines to reach a synaptic depression state, from which the synapses do not recover. The FM1-43 pre-synaptic loading ability, however, is maintained under monocarboxylate, suggesting that SV cycling should not contribute to the synaptic depression state. The NTR recovery was reached by supplementing the monocarboxylate medium with sucrose. However, monocarboxylate addition to sucrose medium does not enhance NTR, but it does when the disaccharide concentration becomes too reduced. Thus, when pyruvate concentrations become too reduced, exogenously supplied L-lactate could be converted to pyruvate and metabolized by the neural mitochondria, triggering the NTR enhancement. SIGNIFICANCE STATEMENT: The question of whether monocarboxylic acids can fuel the Drosophila motoneuron NTR was challenged. Our findings show that exogenously supplied monocarboxylates trigger a large transient synaptic enhancement just under extreme glycolysis reduction but fail to maintain NTR under sustained synaptic demand, still at low frequency stimulation, driven to the synapses to a synaptic depression state. Glycolysis activation, by adding sucrose to the monocarboxylate bath solution, restores the motoneuron NTR ability, giving place to a hexoses role in SV recruitment. Moreover these results suggest exogenously supplied C3 carbon sources could have an additional role beyond providing energetic support for neural activity.


Assuntos
Drosophila , Sinapses , Animais , Drosophila/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/fisiologia , Neurônios Motores/metabolismo , Ácido Pirúvico/farmacologia , Ácido Pirúvico/metabolismo , Lactatos/metabolismo , Carbono/metabolismo , Sacarose/metabolismo
3.
J Surg Case Rep ; 2023(9): rjad491, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37680994

RESUMO

The bipedicled Deep Inferior Epigastric Perforator (DIEP) flap, originally described and primarily utilized in autologous breast reconstruction for specific cases, has expanded its applications to encompass diverse anatomical regions in recent years. This report presents the case of a 69-year-old woman with a recurrent giant thyroid tumor who underwent surgical resection, resulting in a large cervico-thoracic defect effectively reconstructed using a bipedicled DIEP flap. The patient's postoperative recovery was uneventful, and the follow-up assessments revealed a healthy, well-perfused flap that provided sufficient coverage to critical structures, adequate restoration of the region contour, and enough volume to offset potential adverse effects of subsequent radiation therapy. In addition, this report incorporates a concise literature review highlighting the expanding indications of the bipedicled DIEP flap beyond breast reconstruction, showing the versatility and efficacy of the bipedicled DIEP flap in addressing complex soft-tissue defects in various anatomical areas.

4.
J Thromb Haemost ; 21(8): 2202-2212, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37178770

RESUMO

BACKGROUND: Many patients with glioblastoma multiforme (GBM) develop deep venous thrombosis or pulmonary emboli. Cell-free circulating mitochondria increase after brain injury and are associated with coagulopathy. OBJECTIVES: This study evaluated whether mitochondria play a role in the GBM-induced hypercoagulable state. METHODS: We examined the correlation between cell-free circulating mitochondria and venous thrombosis in patients with GBM and the impact of mitochondria on venous thrombosis in mice with inferior vena cava stenosis. RESULTS: Using plasma samples of 82 patients with GBM, we found that patients with GBM had a higher number of mitochondria in their plasma (GBM with venous thromboembolism [VTE],: 2.8 × 107 mitochondria/mL; GBM without VTE, 1.9 × 107 mitochondria/mL) than that in healthy control subjects (n = 17) (0.3 × 107 mitochondria/mL). Interestingly, patients with GBM and VTE (n = 41) had a higher mitochondria concentration than patients with GBM without VTE (n = 41). In a murine model of inferior vena cava stenosis, intravenous delivery of mitochondria resulted in an increased rate of venous thrombosis compared with that in controls (70% and 28%, respectively). Mitochondria-induced venous thrombi were neutrophil-rich and contained more platelets than those in control thrombi. Furthermore, as mitochondria are the only source of cardiolipin in circulation, we compared the concentration of anticardiolipin immunoglobulin G in plasma samples of patients with GBM and found a higher concentration in patients with VTE (optical density, 0.69 ± 0.04) than in those without VTE (optical density, 0.51 ± 0.04). CONCLUSION: We concluded that mitochondria might play a role in the GBM-induced hypercoagulable state. We propose that quantifying circulating mitochondria or anticardiolipin antibody concentrations in patients with GBM might identify patients at increased risk of VTE.


Assuntos
Glioblastoma , Tromboembolia Venosa , Trombose Venosa , Animais , Camundongos , Glioblastoma/complicações , Constrição Patológica/complicações , Fatores de Risco , Trombose Venosa/complicações
5.
JBRA Assist Reprod ; 27(3): 355-359, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36749808

RESUMO

OBJECTIVE: Is self-detection of the endogenous LH surge using a urine testing a reliable method to confirm a successful gonadotropin-releasing hormone agonist (GnRHa) trigger in IVF cycles? METHODS: Prospective observational study including a total of 103 oocyte donation cycles between November 2019 and January 2020. Urine LH testing (Akralab SL, Spain, cut-of value 30 mIU/mL) was performed at home in samples from the first micturition in the morning after the GnRHa trigger and a picture of the result was sent to the nurse coordinator; this information was concealed and only disclosed after oocyte aspiration. RESULTS: From the total group, two cycles were excluded. A total of 101 oocyte donors performed the LH urine testing, all proceeded to oocyte aspiration and were included in final analysis. A total of 85 (84.2%) had a positive LH test and an uneventful oocyte retrieval with good retrieval rates (false positive rate: 0%). A total of 16 had a negative LH test (15.8%) and had a good oocyte retrieval rates (false negative rate: 15.8%). There were no cases of empty follicle syndrome. CONCLUSIONS: Due to a high false negative rate, self-testing of endogenous LH release using a LH urine test when performed approximately 12-hours after triggering does not seem to be a reliable method to predict a suboptimal response to gonadotropin-releasing hormone.


Assuntos
Hormônio Luteinizante , Indução da Ovulação , Humanos , Indução da Ovulação/métodos , Fertilização In Vitro/métodos , Hormônio Liberador de Gonadotropina , Oócitos/fisiologia , Gonadotropina Coriônica
6.
Front Immunol ; 13: 1018047, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203567

RESUMO

The current global platelet supply is often insufficient to meet all the transfusion needs of patients, in particular for those with alloimmune thrombocytopenia. To address this issue, we have developed a strategy employing a combination of approaches to achieve more efficient production of functional megakaryocytes (MKs) and platelets collected from cord blood (CB)-derived CD34+ hematopoietic cells. This strategy is based on ex-vivo expansion and differentiation of MKs in the presence of bone marrow niche-mimicking mesenchymal stem cells (MSCs), together with two other key components: (1) To enhance MK polyploidization, we used the potent pharmacological Rho-associated coiled-coil kinase (ROCK) inhibitor, KD045, resulting in liberation of increased numbers of functional platelets both in-vitro and in-vivo; (2) To evade HLA class I T-cell-driven killing of these expanded MKs, we employed CRISPR-Cas9-mediated ß-2 microglobulin (ß2M) gene knockout (KO). We found that coculturing with MSCs and MK-lineage-specific cytokines significantly increased MK expansion. This was further increased by ROCK inhibition, which induced MK polyploidization and platelet production. Additionally, ex-vivo treatment of MKs with KD045 resulted in significantly higher levels of engraftment and donor chimerism in a mouse model of thrombocytopenia. Finally, ß2M KO allowed MKs to evade killing by allogeneic T-cells. Overall, our approaches offer a novel, readily translatable roadmap for producing adult donor-independent platelet products for a variety of clinical indications.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Trombocitopenia , Animais , Citocinas/farmacologia , Sangue Fetal , Megacariócitos , Camundongos , Linfócitos T , Quinases Associadas a rho
7.
Sci Rep ; 12(1): 17505, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261474

RESUMO

Hominin footprints were recently discovered at Matalascañas (Huelva; South of Iberian Peninsula). They were dated thanks to a previous study in deposits of the Asperillo cliff to 106 ± 19 ka, Upper Pleistocene, making Neandertals the most likely track-makers. In this paper, we report new Optically Stimulated Luminescence dating that places the hominin footprints surface in the range of 295.8 ± 17 ka (MIS 9-MIS 8 transition, Middle Pleistocene). This new age implies that the possible track-makers are individuals more likely from the Neandertal evolutionary lineage. Regardless of the taxon attributed to the Matalascañas footprints, they supplement the existing partial fossil record for the European Middle Pleistocene Hominins being notably the first palaeoanthropological evidence (hominin skeleton or footprints) from the MIS 9 and MIS 8 transition discovered in the Iberian Peninsula, a moment of climatic evolution from warm to cool. Thus, the Matalascañas footprints represent a crucial record for understanding human occupations in Europe in the Pleistocene.


Assuntos
Hominidae , Homem de Neandertal , Animais , Humanos , Fósseis , Europa (Continente) , Luminescência
8.
Musculoskelet Sci Pract ; 62: 102625, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35961064

RESUMO

OBJECTIVE: To analyse the inter- and intra-examiner reliability for the neck flexion-rotation test and the C0-C2 axial rotation test when applied in asymptomatic subjects by two novice physiotherapists. DESIGN: Repeated measures reliability study design. The study was approved by the Research Ethics Committee of [X], in compliance with the Declaration of Helsinki (CSEULS-PI: 004/2020). METHODS: 32 asymptomatic adults were included, recruited by convenience sampling. Two sessions were scheduled for each subject, with an intersession break of 30 min. Two inexperienced raters blinded to their own previous and peer results performed three movements to both sides using the flexion-rotation test and the C0-C2 axial rotation test in randomised order of rater, test and direction. A third researcher collected the data measured by inertial sensors and displayed to the Pro Motion Capture software. RESULTS: Both raters showed good-excellent intra-examiner reliability (ICC(2,3) ranging from 0.88 to 0.94) and moderate to good inter-examiner reliability (ICC(2,3) ranging from 0.58 to 0.86) to measure the rotation ROM with the FRT. The C0-C2 axial rotation test resulted in poor to moderate intra-examiner reliability (ICC(2,3) ranging from 0.33 to 0.74) and poor inter-examiner reliability using (ICC(2,3) ranging from 0.16 to 0.37). CONCLUSION: Although performed by novice raters, the FRT showed good to excellent intra and inter-examiner reliability. Results for the C0-C2 axial rotation test were less reliable. We suggest that novice physiotherapists use the FRT instead of the C0-C2 axial rotation test in order to determine C1-C2 dysfunction.


Assuntos
Vértebras Cervicais , Adulto , Humanos , Reprodutibilidade dos Testes , Fenômenos Biomecânicos , Rotação , Amplitude de Movimento Articular
9.
Cancers (Basel) ; 14(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35626102

RESUMO

The interactions between platelets and cancer cells activate platelets and enhance tumor growth. Platelets increase proliferation and epithelial-mesenchymal transition in cancer cells, inhibit anoikis, enhance the extravasation of cancer cells, and protect circulating tumor cells against natural killer cells. Here, we have identified another mechanism by which platelets dampen the immune attack on cancer cells. We found that platelets can blunt the antitumor immune response by increasing the expression of inhibitory immune checkpoint (PD-L1) on ovarian cancer cells in vitro and in vivo. Platelets increased PD-L1 in cancer cells via contact-dependent (through NF-κB signaling) and contact-independent (through TFGßR1/Smad signaling) pathways. Inhibition of NF-κB or TGFßR1 signaling in ovarian cancer cells abrogated platelet-induced PD-L1 expression. Reducing platelet counts or inhibiting platelet functions reduced the expression of PD-L1 in ovarian cancer. On the other hand, an increase in platelet counts increased the expression of PD-L1 in tumor-bearing mice.

10.
J Thromb Haemost ; 20(1): 104-114, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34608736

RESUMO

BACKGROUND: Podoplanin (PDPN) is a sialylated membrane glycoprotein that binds to C-type lectin-like receptor 2 on platelets resulting in platelet activation. PDPN is expressed on lymphatic endothelial cells, perivascular fibroblasts/pericytes, cancer cells, cancer-associated fibroblasts, and tumor stromal cells. PDPN's expression on malignant epithelial cells plays a role in metastasis. Furthermore, the expression of PDPN in brain tumors (high-grade gliomas) was found to correlate with an increased risk of venous thrombosis. OBJECTIVE: We examined the expression of PDPN and its role in tumor progression and venous thrombosis in ovarian cancer. METHODS: We used mouse models of ovarian cancer and venous thrombosis. RESULTS: Ovarian cancer cells express PDPN and release PDPN-rich extracellular vesicles (EVs), and cisplatin and topotecan (chemotherapies commonly used in ovarian cancer) increase the expression of podoplanin in cancer cells. The expression of PDPN in ovarian cancer cells promotes tumor growth in a murine model of ovarian cancer and that knockdown of PDPN gene expression results in smaller primary tumors. Both PDPN-expressing ovarian cancer cells and their EVs cause platelet aggregation. In a mouse model of venous thrombosis, PDPN-expressing EVs released from HeyA8 ovarian cancer cells produce more frequent thrombosis than PDPN-negative EVs derived from PDPN-knockdown HeyA8 cells. Blood clots induced by PDPN-positive EVs contain more platelets than those in blood clots induced by PDPN-negative EVs. CONCLUSIONS: In summary, our findings demonstrate that the expression of PDPN by ovarian cancer cells promotes tumor growth and venous thrombosis in mice.


Assuntos
Glioma , Neoplasias Ovarianas , Trombose Venosa , Animais , Modelos Animais de Doenças , Células Endoteliais , Camundongos , Agregação Plaquetária , Trombose Venosa/genética
11.
Blood Adv ; 5(7): 1947-1951, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33821990

RESUMO

We and other investigators have shown that platelets promote metastasis and the growth of tumors. Our rationale for conducting this study is that platelets' prometastatic and progrowth effects depend on a close encounter between platelets and cancer cells. This interaction occurs inside blood vessels with circulating tumor cells and outside blood vessels with cancer cells residing in the tumor parenchyma. Our hypothesis was that platelet extravasation is required for the effect of platelets on tumor growth. Platelets respond to environmental stimuli by activation of G protein-coupled receptors on their surface. We investigated the impact of various platelet G proteins on the growth of ovarian cancer tumors and platelet extravasation. We used mice with platelet-specific deficiency of Gαi2 (Gi), Gα13 (G13), or Gαq (Gq) in a syngeneic ovarian cancer model. We measured the total weight of tumor nodules resected from tumor-bearing mice. We developed methods for automated whole-slide image acquisition and unbiased computerized image analysis to quantify extravasated platelets. We compared the number of platelets inside tumor nodules of platelet G protein-deficient tumor-bearing mice. We found that deficiency of Gi and G13, but not Gq, in platelets resulted in smaller tumors compared with those in corresponding littermates. Deficiency of Gi and G13 in platelets reduced the number of extravasated platelets by >90%, but deficiency of Gq did not reduce the number of extravasated platelets significantly. The lack of Gi or G13 in platelets reduced platelet extravasation into the tumor and tumor growth.


Assuntos
Plaquetas , Neoplasias Ovarianas , Animais , Modelos Animais de Doenças , Feminino , Proteínas de Ligação ao GTP , Humanos , Camundongos
12.
Sci Rep ; 11(1): 4103, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707474

RESUMO

Here, we report the recent discovery of 87 Neandertal footprints on the Southwest of the Iberian Peninsula (Doñana shoreline, Spain) located on an upper Pleistocene aeolian littoral setting (about 106 ± 19 kyr). Morphometric comparisons, high resolution digital photogrammetric 3D models and detailed sedimentary analysis have been provided to characterized the footprints and the palaeoenvironment. The footprints were impressed in the shoreline of a hypersaline swamped area related to benthic microbial mats, close to the coastline. They have a rounded heel, a longitudinal arch, relatively short toes, and adducted hallux, and represent the oldest upper Pleistocene record of Neandertal footprints in the world. Among these 87 footprints, 31 are longitudinally complete and measure from 14 to 29 cm. The calculated statures range from 104 to 188 cm, with half of the data between 130 and 150 cm. The wide range of sizes of the footprints suggests the existence of a social group integrated by individuals of different age classes but dominated, however, by non-adult individuals. The footprints, which are outside the flooded area are oriented perpendicular to the shoreline. These 87 footprints reinforce the ecological scenario of Neandertal groups established in coastal areas.

13.
J Am Soc Echocardiogr ; 33(9): 1106-1115, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32564979

RESUMO

BACKGROUND: Left ventricular wall thickness (LVWT) measurement is key in the diagnostic and prognostic assessment of hypertrophic cardiomyopathy (HCM). Recent investigations have highlighted discrepancies in LVWT by cardiac magnetic resonance (CMR) and standard echocardiography (S-Echo) in this condition. The aim of this study was to elucidate the role of contrast-enhanced echocardiography (C-Echo) to optimize LVWT measurement in patients with HCM. METHODS: Fifty patients with HCM were prospectively enrolled, undergoing S-Echo, C-Echo, and CMR. Blinded LVWT measurements were performed according to a 16-segment left ventricular model using all three imaging techniques. Agreement between both echocardiographic modalities and CMR (as the reference technique) at the segmental level was tested using Bland-Altman analyses. Reproducibility on segmental measurements by S-Echo and C-Echo was also investigated. RESULTS: Patients' mean age was 47 ± 21 years, and 35 (70%) were men. Maximal mean LVWT by S-Echo (20.1 ± 3.8 mm) was greater than the values derived using C-Echo (17.6 ± 4.0 mm, P < .01) and CMR (17.7 ± 4.5 mm, P < .01), with no statistically significant difference between the latter two. Segmental Bland-Altman models demonstrated globally smaller bias and narrower 95% limits of agreement for C-Echo compared with S-Echo. Across all left ventricular segments, LVWT by C-Echo was 2.4 mm lower (range, 1.0-2.5 mm) than that derived by S-Echo, which accounted for a 25% intertechnique difference. Regarding maximal LVWT, the mean absolute difference between C-Echo and S-Echo was 3.0 ± 1.9 mm (range, 0.0-7.9 mm), which represented a 15% intertechnique change. Data analyses demonstrated globally less intra- and interobserver variability in segmental LVWT derived from C-Echo compared with S-Echo. CONCLUSIONS: C-Echo rendered LVWT measurements closer to those derived by the reference technique (CMR) and improved reproducibility compared with S-Echo. C-Echo represents a suitable tool for LVWT measurement in patients with HCM as an alternative to CMR whenever this is not available or possible.


Assuntos
Cardiomiopatia Hipertrófica , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Recém-Nascido , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Reprodutibilidade dos Testes
14.
Gynecol Endocrinol ; 36(7): 657-659, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31876208

RESUMO

We report the first case of OHSS following GnRH agonist trigger for final follicular maturation in random start ovarian stimulation for egg-donation cycles during inadvertent concomitant early pregnancy. As an additional note, the sustained activity exerted by the increasing endogenous hCG production seemed to be responsible for the suboptimal performance in terms of oocyte yield in the current case. OHSS can occur in random-start stimulations protocols even after the use of a GnRH agonist for triggering in case of concomitant unnoticed early pregnancy especially if stimulation is commenced in the periovulatory/luteal phase. The present case report introduces a note of extreme caution when proceeding with this protocol in an otherwise fertile population (egg-donors, elective or oncologic oocyte cryopreservation).


Assuntos
Doação de Oócitos , Síndrome de Hiperestimulação Ovariana/diagnóstico , Indução da Ovulação/efeitos adversos , Complicações na Gravidez/diagnóstico , Aborto Induzido , Adulto , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Fármacos para a Fertilidade Feminina/efeitos adversos , Idade Gestacional , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Achados Incidentais , Doação de Oócitos/efeitos adversos , Doação de Oócitos/métodos , Recuperação de Oócitos/efeitos adversos , Recuperação de Oócitos/métodos , Síndrome de Hiperestimulação Ovariana/etiologia , Indução da Ovulação/métodos , Gravidez , Primeiro Trimestre da Gravidez
15.
Educ. med. super ; 33(3): e1718, jul.-set. 2019. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1089925

RESUMO

Introducción: El aprendizaje basado en problemas es una estrategia educativa que se fortalece con tutores pares. La dificultad para contar con docentes interesados en ser tutores y con tiempo disponible, motivó a crear un programa de tutoría de pares en aprendizaje, basado en problemas en la Escuela de Medicina de la Universidad Austral de Chile. Objetivo: Difundir el programa de formación de estudiantes tutores en aprendizaje basado en problemas para implementarlo en otras universidades en las carreras que lo requieran. Métodos: Se describió el plan de formación de tutores pares en aprendizaje basado en problemas. Los estudiantes de cursos superiores fueron seleccionados según sus méritos académicos y asistieron a talleres de capacitación centrados en el manejo de la tutoría y el fortalecimiento de las competencias genéricas. Durante el aprendizaje basado en problemas se hicieron un seguimiento permanente y reuniones formales con los tutores. Al finalizar, se aplicaron encuestas de opinión para evaluar el desempeño de los alumnos, y cada tutor recibió un pequeño reconocimiento económico y créditos en horas de ayudantía. Resultados: Este programa generó un alto interés entre los estudiantes, fue bien evaluado y permitió formar a 120 estudiantes como facilitadores en aprendizaje basado en problemas. Las encuestas realizadas a 45 estudiantes y 45 tutores revelaron un alto grado de satisfacción en todos los ámbitos consultados. Conclusiones: Los tutores pares son la mejor manera de trabajar el aprendizaje basado en problemas. Estos requieren de una capacitación previa para contar con las herramientas necesarias de su rol de facilitadores, así como seguimiento, evaluación y apoyo permanente(AU)


Introduction: Problem-based learning is an educational strategy which may be strengthened by peer tutoring. The difficulty to engage teachers interested in being tutors and the scarcity of available time led to the development of a problem-based peer tutoring learning program at the Medical School of the Austral University of Chile. Objective: Disseminate information about the problem-based learning student tutor training program so as to implement it at other universities in the majors requiring it. Methods: A description was made of the problem-based learning peer tutor training program. Students selected from higher courses according to their academic merits attended training workshops dealing with tutoring management and the strengthening of generic competences. Problem-based learning sessions included permanent follow-up and formal meetings with tutors. At the end, opinion surveys were applied to evaluate the performance of students, and each tutor received a small economic incentive and credits in teaching assistance hours. Results: Students were highly motivated by the program, which was evaluated as satisfactory and made it possible to train 120 students as problem-based learning facilitators. The surveys applied to 45 students and 45 tutors revealed a high level of satisfaction in all the areas consulted. Conclusions: Peer tutoring is the best way to conduct problem-based learning. Tutors require previous training so they have the tools required by their role as facilitators, as well as permanent follow-up, evaluation and support(AU)


Assuntos
Humanos , Faculdades de Medicina , Estudantes de Medicina , Aprendizagem Baseada em Problemas , Identidade de Gênero
16.
Indian J Plast Surg ; 52(1): 81-92, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31456616

RESUMO

Lymphedema refers to the accumulation of protein-rich fluid in the interstitial spaces. This can occur secondary to congenital malformation of the lymphatic channels or nodes or as a result of an insult that damages appropriately formed channels and nodes. Stagnant, protein-rich lymph initiates an inflammatory response that leads to adipocyte proliferation, fibrous tissue deposition, and increased susceptibility to infections. The end result is permanent disfigurement and dermal changes. Early and accurate diagnosis is essential, since lymphedema is a chronic and progressive problem. When lymphedema affects the lower extremity, it is important to manage it in a way that preserves function and mobility. Early diagnosis also allows for a proactive rather than reactive approach to treatment and utilization of novel physiologic procedures, such as lymphovenous anastomosis and vascularized lymph node transfer. Such interventions slow down disease progression and reduce morbidity by allowing the surgeon to salvage the remaining functional lymphatic channels. When physiologic procedures fail or when faced with a delayed presentation, the addition of excisional procedures can provide a more comprehensive treatment of this debilitating disease. The aim of this article is to review the most current concepts in the surgical management of lower extremity lymphedema.

17.
Ecol Evol ; 9(16): 9185-9206, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31463015

RESUMO

Aggressive sibling competition for parental food resources is relatively infrequent in animals but highly prevalent and extreme among certain bird families, particularly accipitrid raptors (Accipitriformes). Intense broodmate aggression within this group is associated with a suite of traits including a large adult size, small broods, low provisioning rates, and slow development. In this study, we apply phylogenetic comparative analyses to assess the relative importance of several behavioral, morphological, life history, and ecological variables as predictors of the intensity of broodmate aggression in 65 species of accipitrid raptors. We show that intensity of aggression increases in species with lower parental effort (small clutch size and low provisioning rates), while size effects (adult body mass and length of nestling period) are unimportant. Intense aggression is more closely related to a slow life history pace (high adult survival coupled with a restrained parental effort), rather than a by-product of allometry or food limitation. Consideration of several ecological variables affecting prey abundance and availability reveals that certain lifestyles (e.g., breeding in aseasonal habitats or hunting for more agile prey) may slow a species' life history pace and favor the evolution of intense broodmate aggression.

18.
Acta Med Port ; 32(7-8): 483-487, 2019 08 01.
Artigo em Português | MEDLINE | ID: mdl-31445527

RESUMO

Coronary heart disease is the single most common cause of death globally, accounting for one-third of all deaths. However, with falling coronary heart disease mortality rates, an increasing number of people live with the disease and may need support to manage their symptoms and prognosis. A complex intervention that may involve a variety of therapies, cardiac rehabilitation includes exercise, risk factor education, behavioral change, psychological support, and strategies that are aimed at targeting traditional risk factors for cardiovascular disease. Cardiac rehabilitation is an essential part of contemporary heart disease care and is considered a priority in countries with a high prevalence of coronary heart disease. This Cochrane systematic review constitutes an update of a Cochrane review published in 2011, having identified 16 new trials (3872 participants), predominantly post-myocardial infarction and post-revascularization patients. Therefore, it included 63 randomized trials looking at the effectiveness and cost-effectiveness of exercise-based cardiac rehabilitation in patients with coronary heart disease. The quality of the evidence ranged from low to moderate. The main results highlight the effect of cardiac rehabilitation, in comparison with absence of physical exercise, in the reduction in cardiovascular mortality, with no reduction, however, in total mortality. The overall risk of hospital admissions was reduced with cardiac rehabilitation but there was no significant impact on the risk of myocardial infarction, coronary artery bypass graft or percutaneous coronary intervention. This paper aims to summarize and discuss the main results and conclusions of this systematic review, as well as its implications for the daily clinical practice.


A doença coronária, responsável por um terço de todas as mortes, é a causa de morte mais comum em todo o mundo. Todavia, com o decréscimo das taxas de mortalidade associadas a esta patologia, observa-se um número crescente de doentes com a doença, com aumento da necessidade de gestão dos seus sintomas e prognóstico. A reabilitação cardíaca, componente essencial do tratamento contemporâneo da doença arterial coronária, é uma intervenção complexa que envolve variadas técnicas, incluindo exercício físico, correção dos fatores de risco cardiovasculares tradicionais, terapia comportamental e apoio psicológico, sendo considerada uma prioridade em países em que a prevalência da doença é elevada. Esta revisão sistemática Cochrane constitui uma atualização de uma revisão Cochrane publicada em 2011, tendo identificado 16 novos ensaios clínicos (3872 doentes), predominantemente em status pós-enfarte agudo do miocárdio e pós-cirurgia de revascularização miocárdica. Incluiu, assim, 63 ensaios clínicos aleatorizados que estudaram a eficácia e o custo-efetividade da reabilitação cardíaca baseada no exercício físico, em pacientes com doença arterial coronária. A confiança na evidência científica variou de baixa a moderada. Dos principais resultados destaca-se o efeito da reabilitação cardíaca, em comparação com a ausência de exercício físico, na redução na mortalidade cardiovascular, todavia sem redução da mortalidade total. Apesar da reabilitação cardíaca ter diminuído o risco global de internamento hospitalar, o mesmo não se verificou para o risco de enfarte, cirurgia de revascularização miocárdica ou intervenção coronária percutânea. Neste artigo sumarizam-se e discutem-se os principais resultados, conclusões e implicações desta revisão sistemática para a prática clínica.


Assuntos
Reabilitação Cardíaca , Doença das Coronárias , Exercício Físico , Terapia por Exercício , Humanos , Qualidade de Vida
20.
Neuroscience ; 396: 66-72, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30458219

RESUMO

Drosophila phototransduction occurs in light-sensitive microvilli arranged in a longitudinal structure of the photoreceptor, termed the rhabdomere. Rhodopsin (Rh), isomerized by light, couples to G-protein, which activates phospholipase C (PLC), which in turn cleaves phosphatidylinositol 4,5-bisphosphate (PIP2) generating diacylglycerol (DAG), inositol trisphosphate and H+. This pathway opens the light-dependent channels, transient receptor potential (TRP) and transient receptor potential like (TRPL). PLC and TRP are held together in a protein assembly by the scaffold protein INAD. We report that the channels can be photoactivated in on-cell rhabdomeric patches and in excised patches by DAG. In excised patches, addition of PLC-activator, m-3M3FBS, or G-protein-activator, GTP-γ-S, opened TRP. These reagents were ineffective in PLC-mutant norpA and in the presence of PLC inhibitor U17322. However, DAG activated TRP even when PLC was pharmacologically or mutationally suppressed. These observations indicate that PLC, G-protein, and TRP were retained functional in these patches. DAG also activated TRP in the protein kinase C (PKC) mutant, inaC, excluding the possibility that PKC could mediate DAG-dependent TRP activation. Labeling diacylglycerol kinase (DGK) by fusion of fluorescent mCherry (mCherry-DGK) indicates that DGK, which returns DAG to dark levels, is highly expressed in the microvilli. In excised patches, TRP channels could be light-activated in the presence of GTP, which is required for G-protein activation. The evidence indicates that the proteins necessary for phototransduction are retained functionally after excision and that DAG is necessary and sufficient for TRP opening. This work opens up unique possibilities for studying, in sub-microscopic native membrane patches, the ubiquitous phosphoinositide signaling pathway and its regulatory mechanisms in unprecedented detail.


Assuntos
Ativação do Canal Iônico/efeitos da radiação , Luz , Microvilosidades/metabolismo , Microvilosidades/efeitos da radiação , Células Fotorreceptoras de Invertebrados/citologia , Canais de Potencial de Receptor Transitório/metabolismo , Canais de Potencial de Receptor Transitório/efeitos da radiação , Animais , Diacilglicerol Quinase/biossíntese , Diglicerídeos/farmacologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/isolamento & purificação , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/efeitos da radiação , Drosophila melanogaster , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Proteína Quinase C/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Sulfonamidas/farmacologia , Canais de Potencial de Receptor Transitório/isolamento & purificação , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/genética
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