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1.
Plants (Basel) ; 12(22)2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38005805

RESUMEN

Propolis, a natural resin created by bees, has garnered significant attention from both the scientific community and industry due to an impressive range of bioactivities. Nonetheless, the intrinsic variability in its chemical composition and bioactive profiles has been hindering propolis' full potential use. We previously showed that ethanol extracts (EEs) of a Portuguese propolis sample (Gerês) collected over four consecutive years displayed similar chemical and biological profiles, a constancy never documented before. However, the characteristics of the unprocessed samples of Gerês propolis were never described. Hence, the central objective of this study is to assess the quality parameters of unprocessed propolis samples collected from Gerês (G), over a four-year period (2019-2022), alongside the analysis of the chemical composition and bioactivities of the EEs prepared with the same raw samples. The ash, wax, balsam and water contents of the unprocessed samples-G19 to G22-showed minor fluctuations, likely attributed to uncontrollable natural events impacting the propolis source and collection process. On the other hand, the antimicrobial and antioxidant activities of all the four ethanol extracts (G19.EE-G22.EE) consistently align with prior studies. Furthermore, the Gerês propolis extracts showed remarkable uniformity in chemical composition parameters too, particularly concerning total polyphenol, flavonoid and ortho-diphenol contents. In summary, our research reinforces the beneficial properties of propolis and show that extracts' bioactivities remain within the reference ranges for Gerês propolis, despite minor differences in unprocessed samples, suggesting a consistent action over time. Thus, this work could be instrumental towards the establishment of standard parameters for propolis applications, offering valuable insights to this field of propolis research.

2.
Cell Stem Cell ; 30(10): 1299-1314.e9, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37802036

RESUMEN

Cell replacement therapies for Parkinson's disease (PD) based on transplantation of pluripotent stem cell-derived dopaminergic neurons are now entering clinical trials. Here, we present quality, safety, and efficacy data supporting the first-in-human STEM-PD phase I/IIa clinical trial along with the trial design. The STEM-PD product was manufactured under GMP and quality tested in vitro and in vivo to meet regulatory requirements. Importantly, no adverse effects were observed upon testing of the product in a 39-week rat GLP safety study for toxicity, tumorigenicity, and biodistribution, and a non-GLP efficacy study confirmed that the transplanted cells mediated full functional recovery in a pre-clinical rat model of PD. We further observed highly comparable efficacy results between two different GMP batches, verifying that the product can be serially manufactured. A fully in vivo-tested batch of STEM-PD is now being used in a clinical trial of 8 patients with moderate PD, initiated in 2022.


Asunto(s)
Células Madre Embrionarias Humanas , Enfermedad de Parkinson , Humanos , Ratas , Animales , Enfermedad de Parkinson/terapia , Distribución Tisular , Diferenciación Celular/fisiología , Trasplante de Células Madre/métodos , Neuronas Dopaminérgicas/fisiología
3.
Mol Ther Methods Clin Dev ; 29: 381-394, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37251982

RESUMEN

Cell therapy for Parkinson's disease has experienced substantial growth in the past decades with several ongoing clinical trials. Despite increasing refinement of differentiation protocols and standardization of the transplanted neural precursors, the transcriptomic analysis of cells in the transplant after its full maturation in vivo has not been thoroughly investigated. Here, we present spatial transcriptomics analysis of fully differentiated grafts in their host tissue. Unlike earlier transcriptomics analyses using single-cell technologies, we observe that cells derived from human embryonic stem cells (hESCs) in the grafts adopt mature dopaminergic signatures. We show that the presence of phenotypic dopaminergic genes, which were found to be differentially expressed in the transplants, is concentrated toward the edges of the grafts, in agreement with the immunohistochemical analyses. Deconvolution shows dopamine neurons being the dominating cell type in many features beneath the graft area. These findings further support the preferred environmental niche of TH-positive cells and confirm their dopaminergic phenotype through the presence of multiple dopaminergic markers.

4.
Stem Cell Reports ; 17(1): 159-172, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34971563

RESUMEN

Transplantation in Parkinson's disease using human embryonic stem cell (hESC)-derived dopaminergic (DA) neurons is a promising future treatment option. However, many of the mechanisms that govern their differentiation, maturation, and integration into the host circuitry remain elusive. Here, we engrafted hESCs differentiated toward a ventral midbrain DA phenotype into the midbrain of a preclinical rodent model of Parkinson's disease. We then injected a novel DA-neurotropic retrograde MNM008 adeno-associated virus vector capsid, into specific DA target regions to generate starter cells based on their axonal projections. Using monosynaptic rabies-based tracing, we demonstrated for the first time that grafted hESC-derived DA neurons receive distinctly different afferent inputs depending on their projections. The similarities to the host DA system suggest a previously unknown directed circuit integration. By evaluating the differential host-to-graft connectivity based on projection patterns, this novel approach offers a tool to answer outstanding questions regarding the integration of grafted hESC-derived DA neurons.


Asunto(s)
Diferenciación Celular , Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Sinapsis/metabolismo , Biomarcadores , Rastreo Celular , Expresión Génica , Genes Reporteros , Factores de Intercambio de Guanina Nucleótido/genética , Humanos , Mesencéfalo/metabolismo , Fenotipo , Proteínas Serina-Treonina Quinasas/genética , Trasplante de Células Madre
5.
Int J Surg Case Rep ; 87: 106418, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34583256

RESUMEN

INTRODUCTION: Male breast cancer has a low incidence, and its metastases are considered even rarer and a sign of seriousness for the patient. Breast metastases are difficult to diagnose even in female patients, with few cases of gastric metastasis described in the current literature. PRESENTATION OF CASE: Male patient, 54 years old, obese, diagnosed with breast cancer for 8 years, underwent 5 years of cancer follow-up. After this period, he began to experience epigastric pain and weight loss, among other symptoms. Endoscopy was performed, showing rounded elevated lesions with central depression. After anatomopathological and biochemical tests, a diagnosis of differentiated carcinoma as a metastasis of breast origin was concluded. DISCUSSION: MBC is rare when compared to the incidence in females. Its risk factors differ between genders, and due to its rarity, there are few studies in the male population. This fact makes the evaluation of metastases more difficult. Gastric metastasis has a very low incidence even in women, approximately 8.9% of all breast cancer metastasis's locations. Other pathologies can mimic GM, always associating anatomopathological and biochemical tests. Oncological follow-up must always be carried out, and the possibility of screening must be evaluated. CONCLUSION: Despite the rare incidence and little information in the literature, the association between MBC and GM should be considered. Currently, there is no guidance for conducting systematic screenings and treatment is usually palliative due to the severity of the disease.

6.
Front Cell Dev Biol ; 8: 443, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32626706

RESUMEN

Mesencephalic dopaminergic (mDA) neurons derived from pluripotent stem cells (PSCs) have proven to be pivotal for disease modeling studies and as a source of transplantable tissue for regenerative therapies in Parkinson's disease (PD). Current differentiation protocols can generate standardized and reproducible cell products of dopaminergic neurons that elicit the characteristic transcriptional profile of ventral midbrain. Nonetheless, dopamine neurons residing in the mesencephalon comprise distinct groups of cells within diffusely defined anatomical boundaries and with distinct functional, electrophysiological, and molecular properties. Here we review recent single cell sequencing studies that are shedding light on the neuronal heterogeneity within the mesencephalon and discuss how resolving the complex molecular profile of distinct sub-populations within this region could help refine patterning and quality control assessment of PSC-derived mDA neurons to subtype-specificity in vitro. In turn, such advances would have important impact in improving cell replacement therapy, disease mechanistic studies and drug screening in PD.

8.
Proc Natl Acad Sci U S A ; 117(26): 15209-15220, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32541058

RESUMEN

Preclinical assessment of the therapeutic potential of dopamine (DA) neuron replacement in Parkinson's disease (PD) has primarily been performed in the 6-hydroxydopamine toxin model. While this is a good model to assess graft function, it does not reflect the pathological features or progressive nature of the disease. In this study, we establish a humanized transplantation model of PD that better recapitulates the main disease features, obtained by coinjection of preformed human α-synuclein (α-syn) fibrils and adeno-associated virus (AAV) expressing human wild-type α-syn unilaterally into the rat substantia nigra (SN). This model gives rise to DA neuron dysfunction and progressive loss of DA neurons from the SN and terminals in the striatum, accompanied by extensive α-syn pathology and a prominent inflammatory response, making it an interesting and relevant model in which to examine long-term function and integrity of transplanted neurons in a PD-like brain. We transplanted DA neurons derived from human embryonic stem cells (hESCs) into the striatum and assessed their survival, growth, and function over 6 to 18 wk. We show that the transplanted cells, even in the presence of ongoing pathology, are capable of innervating the DA-depleted striatum. However, on closer examination of the grafts, we found evidence of α-syn pathology in the form of inclusions of phosphorylated α-syn in a small fraction of the grafted DA neurons, indicating host-to-graft transfer of α-syn pathology, a phenomenon that has previously been observed in PD patients receiving fetal tissue grafts but has not been possible to demonstrate and study in toxin-based animal models.


Asunto(s)
Células Madre Embrionarias/fisiología , Trasplante de Células Madre , Sinucleinopatías , alfa-Sinucleína/metabolismo , Animales , Supervivencia Celular , Neuronas Dopaminérgicas/metabolismo , Regulación hacia Abajo , Femenino , Humanos , Inflamación , Degeneración Nerviosa , Ratas , Ratas Sprague-Dawley , Sustancia Negra/citología
9.
Nat Commun ; 11(1): 2434, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32415072

RESUMEN

Cell replacement is a long-standing and realistic goal for the treatment of Parkinson's disease (PD). Cells for transplantation can be obtained from fetal brain tissue or from stem cells. However, after transplantation, dopamine (DA) neurons are seen to be a minor component of grafts, and it has remained difficult to determine the identity of other cell types. Here, we report analysis by single-cell RNA sequencing (scRNA-seq) combined with comprehensive histological analyses to characterize intracerebral grafts from human embryonic stem cells (hESCs) and fetal tissue after functional maturation in a pre-clinical rat PD model. We show that neurons and astrocytes are major components in both fetal and stem cell-derived grafts. Additionally, we identify a cell type closely resembling a class of recently identified perivascular-like cells in stem cell-derived grafts. Thus, this study uncovers previously unknown cellular diversity in a clinically relevant cell replacement PD model.


Asunto(s)
Neuronas Dopaminérgicas/citología , Enfermedad de Parkinson/terapia , Trasplante de Células Madre , Células Madre/citología , Animales , Encéfalo/metabolismo , Diferenciación Celular , Cuerpo Estriado , Modelos Animales de Enfermedad , Dopamina/metabolismo , Células Madre Embrionarias/citología , Femenino , Supervivencia de Injerto , Humanos , Familia de Multigenes , RNA-Seq , Ratas , Ratas Desnudas , Regeneración , Análisis de la Célula Individual , Transcriptoma
10.
J Addict Dis ; 38(2): 113-121, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32193994

RESUMEN

Eating addiction is an important condition related to obesity. The Addiction-like Eating Behavior Scale (AEBS) was recently validated in English to evaluate addictive eating behaviors. To perform the translation, cultural adaptation, and validation of the AEBS scale to Portuguese to identify eating addictions in the Brazilian population. The AEBS translation, adaptation, and validation followed previously published criteria, including the steps of translation, back translation, evaluation by a committee of judges, and a pretest with 40 students. Subsequently, 150 students from the Medical School at the Recife Campus of the Federal University of Pernambuco were tested using the AEBS-Portuguese version (AEBS-p). Of these, 37 were evaluated a second time for a test-retest analysis. For data collection, 5 instruments were used: the AEBS-p, a modified version of the Yale Food Addiction Scale 2.0 (mYFAS 2.0)-Portuguese version, the Patient Health Questionnaire-9, the Binge Eating Scale (BES), and the Socio-demographic Questionnaire. The AEBS-p showed good reliability, based on a significant internal consistency value (Cronbach's alpha = 0.91), and good correlation in the test-retest evaluation. A committee of judges considered the content validity appropriate. Convergent validation was positive with the mYFAS 2.0 and BES (p < 0.001). The AEBS-p showed a significant correlation with body mass index (BMI) (p < 0.001) and significantly predicted variance in BMI that was accounted for by both the mYFAS 2.0 and BES (p = 0.022). The AEBS-p demonstrated good reliability and validity for evaluating addictive eating behaviors in the Brazilian population.


Asunto(s)
Conducta Alimentaria/psicología , Adicción a la Comida/diagnóstico , Escalas de Valoración Psiquiátrica/normas , Adulto , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Portugal , Psicometría , Reproducibilidad de los Resultados , Estudiantes , Traducción , Universidades , Adulto Joven
11.
Proc Natl Acad Sci U S A ; 116(52): 27053-27062, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31818949

RESUMEN

Adeno-associated virus (AAV) capsid modification enables the generation of recombinant vectors with tailored properties and tropism. Most approaches to date depend on random screening, enrichment, and serendipity. The approach explored here, called BRAVE (barcoded rational AAV vector evolution), enables efficient selection of engineered capsid structures on a large scale using only a single screening round in vivo. The approach stands in contrast to previous methods that require multiple generations of enrichment. With the BRAVE approach, each virus particle displays a peptide, derived from a protein, of known function on the AAV capsid surface, and a unique molecular barcode in the packaged genome. The sequencing of RNA-expressed barcodes from a single-generation in vivo screen allows the mapping of putative binding sequences from hundreds of proteins simultaneously. Using the BRAVE approach and hidden Markov model-based clustering, we present 25 synthetic capsid variants with refined properties, such as retrograde axonal transport in specific subtypes of neurons, as shown for both rodent and human dopaminergic neurons.

12.
AME Case Rep ; 3: 44, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31872179

RESUMEN

Ingestion of small objects by children became worrisome as the number of cases increased over the years. Consequences such as intestinal obstruction or even infection of the gastrointestinal tract are becoming more frequent since even in majority cases there is having only an expectant conduct, complications can occur. Also, the combination of two elements such as punctiform metallic materials and imams cause fistula formation in loops with greater ease, granulomas in the intestines, perforation, and can progress to peritonitis or abscesses, as well as having considerable morbidity.

13.
Cell Rep ; 28(13): 3462-3473.e5, 2019 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-31553914

RESUMEN

Cell replacement is currently being explored as a therapeutic approach for neurodegenerative disease. Using stem cells as a source, transplantable progenitors can now be generated under conditions compliant with clinical application in patients. In this study, we elucidate factors controlling target-appropriate innervation and circuitry integration of human embryonic stem cell (hESC)-derived grafts after transplantation to the adult brain. We show that cell-intrinsic factors determine graft-derived axonal innervation, whereas synaptic inputs from host neurons primarily reflect the graft location. Furthermore, we provide evidence that hESC-derived dopaminergic grafts transplanted in a long-term preclinical rat model of Parkinson's disease (PD) receive synaptic input from subtypes of host cortical, striatal, and pallidal neurons that are known to regulate the function of endogenous nigral dopamine neurons. This refined understanding of how graft neurons integrate with host circuitry will be important for the design of clinical stem-cell-based replacement therapies for PD, as well as for other neurodegenerative diseases.


Asunto(s)
Ganglios Basales/fisiopatología , Células Madre Embrionarias Humanas/metabolismo , Enfermedad de Parkinson/genética , Animales , Modelos Animales de Enfermedad , Humanos , Ratones Desnudos , Ratas
14.
J Comp Neurol ; 526(13): 2133-2146, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30007046

RESUMEN

Dopamine (DA) neurons derived from human embryonic stem cells (hESCs) are a promising unlimited source of cells for cell replacement therapy in Parkinson's disease (PD). A number of studies have demonstrated functionality of DA neurons originating from hESCs when grafted to the striatum of rodent and non-human primate models of PD. However, several questions remain in regard to their axonal outgrowth potential and capacity to integrate into host circuitry. Here, ventral midbrain (VM) patterned hESC-derived progenitors were grafted into the midbrain of 6-hydroxydopamine-lesioned rats, and analyzed at 6, 18, and 24 weeks for a time-course evaluation of specificity and extent of graft-derived fiber outgrowth as well as potential for functional recovery. To investigate synaptic integration of the transplanted cells, we used rabies-based monosynaptic tracing to reveal the origin and extent of host presynaptic inputs to grafts at 6 weeks. The results reveal the capacity of grafted neurons to extend axonal projections toward appropriate forebrain target structures progressively over 24 weeks. The timing and extent of graft-derived dopaminergic fibers innervating the dorsolateral striatum matched reduction in amphetamine-induced rotational asymmetry in the animals where recovery could be observed. Monosynaptic tracing demonstrated that grafted cells integrate with host circuitry 6 weeks after transplantation, in a manner that is comparable with endogenous midbrain connectivity. Thus, we demonstrate that VM patterned hESC-derived progenitors grafted to midbrain have the capacity to extensively innervate appropriate forebrain targets, integrate into the host circuitry and that functional recovery can be achieved when grafting fetal or hESC-derived DA neurons to the midbrain.


Asunto(s)
Neuronas Dopaminérgicas/fisiología , Neuronas Dopaminérgicas/trasplante , Mesencéfalo/cirugía , Vías Nerviosas/fisiología , Células-Madre Neurales/fisiología , Células-Madre Neurales/trasplante , Trastornos Parkinsonianos/cirugía , Prosencéfalo/fisiología , Sinapsis/fisiología , Anfetamina/farmacología , Animales , Inhibidores de Captación de Dopamina/farmacología , Femenino , Humanos , Hidroxidopaminas , Ratones , Fibras Nerviosas/fisiología , Trastornos Parkinsonianos/inducido químicamente , Ratas Desnudas , Trasplante de Células Madre , Conducta Estereotipada/efectos de los fármacos
15.
Stem Cell Reports ; 9(4): 1207-1220, 2017 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-28943253

RESUMEN

Human pluripotent stem cell (hPSC)-derived mesencephalic dopaminergic (mesDA) neurons can relieve motor deficits in animal models of Parkinson's disease (PD). Clinical translation of differentiation protocols requires standardization of production procedures, and surface-marker-based cell sorting is considered instrumental for reproducible generation of defined cell products. Here, we demonstrate that integrin-associated protein (IAP) is a cell surface marker suitable for enrichment of hPSC-derived mesDA progenitor cells. Immunomagnetically sorted IAP+ mesDA progenitors showed increased expression of ventral midbrain floor plate markers, lacked expression of pluripotency markers, and differentiated into mature dopaminergic (DA) neurons in vitro. Intrastriatal transplantation of IAP+ cells sorted at day 16 of differentiation in a rat model of PD resulted in functional recovery. Grafts from sorted IAP+ mesDA progenitors were more homogeneous in size and DA neuron density. Thus, we suggest IAP-based sorting for reproducible prospective enrichment of mesDA progenitor cells in clinical cell replacement strategies.


Asunto(s)
Antígeno CD47/metabolismo , Dopamina/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Células Madre Pluripotentes/citología , Trasplante de Células Madre , Animales , Biomarcadores , Diferenciación Celular , Supervivencia Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/metabolismo , Femenino , Citometría de Flujo , Perfilación de la Expresión Génica , Supervivencia de Injerto , Humanos , Separación Inmunomagnética , Inmunofenotipificación , Mesencéfalo/metabolismo , Ratas , Regeneración
16.
Cell Stem Cell ; 20(1): 135-148, 2017 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-28094017

RESUMEN

Stem cell treatments for neurodegenerative diseases are expected to reach clinical trials soon. Most of the approaches currently under development involve transplantation of immature progenitors that subsequently undergo phenotypic and functional maturation in vivo, and predicting the long-term graft outcome already at the progenitor stage remains a challenge. Here, we took an unbiased approach to identify predictive markers expressed in dopamine neuron progenitors that correlate with graft outcome in an animal model of Parkinson's disease through gene expression analysis of >30 batches of grafted human embryonic stem cell (hESC)-derived progenitors. We found that many of the commonly used markers did not accurately predict in vivo subtype-specific maturation. Instead, we identified a specific set of markers associated with the caudal midbrain that correlate with high dopaminergic yield after transplantation in vivo. Using these markers, we developed a good manufacturing practice (GMP) differentiation protocol for highly efficient and reproducible production of transplantable dopamine progenitors from hESCs.


Asunto(s)
Biomarcadores/metabolismo , Diferenciación Celular , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/trasplante , Enfermedad de Parkinson/terapia , Trasplante de Células Madre , Investigación Biomédica Traslacional , Animales , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula/efectos de los fármacos , Células Cultivadas , Dopamina/metabolismo , Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Femenino , Factor 8 de Crecimiento de Fibroblastos/metabolismo , Células Madre Embrionarias Humanas/efectos de los fármacos , Humanos , Laminina/farmacología , Mesencéfalo/metabolismo , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Núcleo Subtalámico/citología , Núcleo Subtalámico/metabolismo , Factores de Tiempo , Resultado del Tratamiento
17.
Rev. bras. cineantropom. desempenho hum ; 18(3): 311-321, May-June 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-789110

RESUMEN

Abstract The aim of this study was to compare coordination index, propulsive time, duration of stroke phases and kinematic parameters over 200 m front crawl. Variables were compared among four sections of 50 m (T1 to T4) in fifteen competitive swimmers (age: 21.1 ± 7.1 years; height: 180.1 ± 6.1 cm; height: 187.3 ± 8, 1 cm; body mass: 72.1 ± 10.1 kg; better performance in the race: 77.5 ± 4.7% of the world record). Data were obtained with two video cameras (60 Hz - coupled to a cart on rails on the side of the pool) for simultaneous images of the swimmer’s sagittal plan: below the water line and above the water line. Mean stroke rate stroke length, assumed as the mean distance traveled per cycle, and mean swimming speed were obtained with manual timing. Over the 200 m, the coordination index remained unchanged (p >0.05), but there was an increase in the frequency of cycles (p <0.05) and reduction of distance traveled per cycle (p <0.05). Between T1 and T2, there was an increase in the propulsive time (p <0.05) and between T1 and T4, there was an increase in the length of the pull phase (p <0.05). The swimming speed decreased only between T1 and T2 (p <0.05). Over 200 m front crawl, well-trained swimmers increment propulsive time and pull phase duration and frequency of stroke cycles, and such changes may be due to the speed maintenance attempt over the 200 m.


Resumo O objetivo deste estudo foi comparar índice de coordenação, tempo propulsivo, duração das fases da braçada e parâmetros cinemáticos ao longo de 200 m nado crawl. Variáveis foram comparadas entre os quatro trechos de 50 m (T1 a T4) em quinze nadadores competitivos (idade: 21,1 ± 7,1 anos; estatura: 180,1 ± 6,1 cm; envergadura: 187,3 ± 8,1 cm; massa corporal: 72,1 ± 10,1 kg; melhor desempenho na prova: 77,5 ± 4,7% do recorde mundial). Obtiveram-se os dados com duas câmeras de vídeo (60 Hz - acopladas a um carrinho sobre trilhos na lateral da piscina), para imagens simultâneas do plano sagital do nadador: abaixo da linha da água e acima da linha da água. Frequência média de ciclos, comprimento de braçada (assumida como a distância média percorrida pelo corpo a cada ciclo) e velocidade média de nado foram obtidos com cronometragem manual. Ao longo dos 200 m, o índice de coordenação não se alterou (p > 0,05), mas houve incremento da frequência de ciclos (p < 0,05) e redução da distância percorrida por ciclo (p < 0,05). Entre T1 e T2, houve incremento do tempo propulsivo (p < 0,05) e entre T1 e T4, da duração da fase de puxada (p < 0,05). Velocidade de nado diminuiu apenas entre T1 e T2 (p < 0,05). Ao longo de 200 m nado crawl, nadadores bem treinados incrementam tempo propulsivo, duração da fase de puxada e frequência de ciclos de braçadas, tais mudanças podem ser devidas à tentativa de manutenção da velocidade ao longo dos 200 m.

18.
Hum Mov Sci ; 46: 39-51, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26707679

RESUMEN

Developing synchronised player movements for fluent competitive match play is a common goal for coaches of team games. An ecological dynamics approach advocates that intra-team synchronization is governed by locally created information, which specifies shared affordances responsible for synergy formation. To verify this claim we evaluated coordination tendencies in two newly-formed teams of recreational players during association football practice games, weekly, for fifteen weeks (thirteen matches). We investigated practice effects on two central features of synergies in sports teams - dimensional compression and reciprocal compensation here captured through near in-phase modes of coordination and time delays between coupled players during forward and backwards movements on field while attacking and defending. Results verified that synergies were formed and dissolved rapidly as a result of the dynamic creation of informational properties, perceived as shared affordances among performers. Practising once a week led to small improvements in the readjustment delays between co-positioning team members, enabling faster regulation of coordinated team actions. Mean values of the number of player and team synergies displayed only limited improvements, possibly due to the timescales of practice. No relationship between improvements in dimensional compression and reciprocal compensation were found for number of shots, amount of ball possession and number of ball recoveries made. Findings open up new perspectives for monitoring team coordination processes in sport.


Asunto(s)
Rendimiento Atlético/psicología , Conducta Competitiva , Procesos de Grupo , Práctica Psicológica , Fútbol/psicología , Identificación Social , Humanos , Masculino , Orientación , Adulto Joven
19.
Cell Rep ; 12(3): 474-81, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-26166567

RESUMEN

The possibility of directly converting non-neuronal cells into neurons in situ in the brain would open therapeutic avenues aimed at repairing the brain after injury or degenerative disease. We have developed an adeno-associated virus (AAV)-based reporter system that allows selective GFP labeling of reprogrammed neurons. In this system, GFP is turned on only in reprogrammed neurons where it is stable and maintained for long time periods, allowing for histological and functional characterization of mature neurons. When combined with a modified rabies virus-based trans-synaptic tracing methodology, the system allows mapping of 3D circuitry integration into local and distal brain regions and shows that the newly reprogrammed neurons are integrated into host brain.


Asunto(s)
Antígenos/fisiología , Cuerpo Estriado/fisiología , Red Nerviosa/fisiología , Neurogénesis/fisiología , Neuroglía/fisiología , Neuronas/fisiología , Proteoglicanos/fisiología , Animales , Antígenos/biosíntesis , Antígenos/genética , Cuerpo Estriado/citología , Células HEK293 , Humanos , Ratones , Ratones Transgénicos , Red Nerviosa/citología , Red Nerviosa/metabolismo , Neuroglía/citología , Neuroglía/metabolismo , Neuronas/citología , Neuronas/metabolismo , Proteoglicanos/biosíntesis , Proteoglicanos/genética
20.
Stem Cell Reports ; 4(6): 975-83, 2015 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-26004633

RESUMEN

Human embryonic stem cell (hESC)-derived dopamine neurons are currently moving toward clinical use for Parkinson's disease (PD). However, the timing and extent at which stem cell-derived neurons functionally integrate into existing host neural circuitry after transplantation remain largely unknown. In this study, we use modified rabies virus to trace afferent and efferent connectivity of transplanted hESC-derived neurons in a rat model of PD and report that grafted human neurons integrate into the host neural circuitry in an unexpectedly rapid and extensive manner. The pattern of connectivity resembled that of local endogenous neurons, while ectopic connections were not detected. Revealing circuit integration of human dopamine neurons substantiates their potential use in clinical trials. Additionally, our data present rabies-based tracing as a valuable and widely applicable tool for analyzing graft connectivity that can easily be adapted to analyze connectivity of a variety of different neuronal sources and subtypes in different disease models.


Asunto(s)
Rastreo Celular/métodos , Neuronas Dopaminérgicas/citología , Células Madre Embrionarias Humanas/citología , Virus de la Rabia/genética , Animales , Diferenciación Celular , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/trasplante , Femenino , Citometría de Flujo , Vectores Genéticos/genética , Vectores Genéticos/metabolismo , Proteínas Fluorescentes Verdes/genética , Histonas/genética , Humanos , Inmunohistoquímica , Microscopía Confocal , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/terapia , Virus de la Rabia/fisiología , Ratas , Ratas Desnudas , Ratas Sprague-Dawley , Integración Viral/fisiología
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