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Sporadic early-onset Alzheimer's disease (sEOAD) represents a significant but less-studied subtype of Alzheimer's disease (AD). Here, we generated a single-nucleus multiome atlas derived from the postmortem prefrontal cortex, entorhinal cortex, and hippocampus of nine individuals with or without sEOAD. Comprehensive analyses were conducted to delineate cell type-specific transcriptomic changes and linked candidate cis- regulatory elements (cCREs) across brain regions. We prioritized seven conservative transcription factors in glial cells in multiple brain regions, including RFX4 in astrocytes and IKZF1 in microglia, which are implicated in regulating sEOAD-associated genes. Moreover, we identified the top 25 altered intercellular signaling between glial cells and neurons, highlighting their regulatory potential on gene expression in receiver cells. We reported 38 cCREs linked to sEOAD-associated genes overlapped with late-onset AD risk loci, and sEOAD cCREs enriched in neuropsychiatric disorder risk loci. This atlas helps dissect transcriptional and chromatin dynamics in sEOAD, providing a key resource for AD research.
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Sporadic early-onset Alzheimer's disease (sEOAD) represents a significant but less-studied subtype of Alzheimer's disease (AD). Here, we generated a single-nucleus multiome atlas derived from the postmortem prefrontal cortex, entorhinal cortex, and hippocampus of nine individuals with or without sEOAD. Comprehensive analyses were conducted to delineate cell type-specific transcriptomic changes and linked candidate cis- regulatory elements (cCREs) across brain regions. We prioritized seven conservative transcription factors in glial cells in multiple brain regions, including RFX4 in astrocytes and IKZF1 in microglia, which are implicated in regulating sEOAD-associated genes. Moreover, we identified the top 25 altered intercellular signaling between glial cells and neurons, highlighting their regulatory potential on gene expression in receiver cells. We reported 38 cCREs linked to sEOAD-associated genes overlapped with late-onset AD risk loci, and sEOAD cCREs enriched in neuropsychiatric disorder risk loci. This atlas helps dissect transcriptional and chromatin dynamics in sEOAD, providing a key resource for AD research.
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Prion diseases result from the misfolding of the physiological prion protein (PrPC) to a pathogenic conformation (PrPSc). Compelling evidence indicates that prevention and/or reduction of PrPSc replication are promising therapeutic strategies against prion diseases. However, the existence of different PrPSc conformations (or strains) associated with disease represents a major problem when identifying anti-prion compounds. Efforts to identify strain-specific anti-prion molecules are limited by the lack of biologically relevant high-throughput screening platforms to interrogate compound libraries. Here, we describe adaptations to the protein misfolding cyclic amplification (PMCA) technology (able to faithfully replicate PrPSc strains) that increase its throughput to facilitate the screening of anti-prion molecules. The optimized PMCA platform includes a reduction in sample and reagents, as well as incubation/sonication cycles required to efficiently replicate and detect rodent-adapted and cervid PrPSc strains. The visualization of PMCA products was performed via dot blots, a method that contributed to reduced processing times. These technical changes allowed us to evaluate small molecules with previously reported anti-prion activity. This proof-of-principle screening was evaluated for six rodent-adapted prion strains. Our data show that these compounds targeted either none, all or some PrPSc strains at variable concentrations, demonstrating that this PMCA system is suitable to test compound libraries for putative anti-prion molecules targeting specific PrPSc strains. Further analyses of a small compound library against deer prions demonstrate the potential of this new PMCA format to identify strain-specific anti-prion molecules. The data presented here demonstrate the use of the PMCA technique in the selection of prion strain-specific anti-prion compounds.
Assuntos
Proteínas PrPSc , Dobramento de Proteína , Animais , Dobramento de Proteína/efeitos dos fármacos , Proteínas PrPSc/metabolismo , Proteínas PrPSc/química , Camundongos , Doenças Priônicas/tratamento farmacológico , Doenças Priônicas/metabolismo , Príons/metabolismoRESUMO
Synucleinopathies are a group of neurodegenerative diseases (NDs) associated with cerebral accumulation of α-synuclein (αSyn) misfolded aggregates. At this time, there is no effective treatment to stop or slow down disease progression, which in part is due to the lack of an early and objective biochemical diagnosis. In the past 5 years, the seed amplification technology has emerged for highly sensitive identification of these diseases, even at the preclinical stage of the illness. Much research has been done in multiple laboratories to validate the efficacy and reproducibility of this assay. This article provides a comprehensive review of this technology, including its conceptual basis and its multiple applications for disease diagnosis, as well for understanding of the disease biology and therapeutic development.
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Doença de Parkinson , Sinucleinopatias , alfa-Sinucleína , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Humanos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Sinucleinopatias/genética , Sinucleinopatias/metabolismo , AnimaisRESUMO
Parkinson's disease and dementia with Lewy bodies are currently defined by their clinical features, with α-synuclein pathology as the gold standard to establish the definitive diagnosis. We propose that, given biomarker advances enabling accurate detection of pathological α-synuclein (ie, misfolded and aggregated) in CSF using the seed amplification assay, it is time to redefine Parkinson's disease and dementia with Lewy bodies as neuronal α-synuclein disease rather than as clinical syndromes. This major shift from a clinical to a biological definition of Parkinson's disease and dementia with Lewy bodies takes advantage of the availability of tools to assess the gold standard for diagnosis of neuronal α-synuclein (n-αsyn) in human beings during life. Neuronal α-synuclein disease is defined by the presence of pathological n-αsyn species detected in vivo (S; the first biological anchor) regardless of the presence of any specific clinical syndrome. On the basis of this definition, we propose that individuals with pathological n-αsyn aggregates are at risk for dopaminergic neuronal dysfunction (D; the second biological anchor). Our biological definition establishes a staging system, the neuronal α-synuclein disease integrated staging system (NSD-ISS), rooted in the biological anchors (S and D) and the degree of functional impairment caused by clinical signs or symptoms. Stages 0-1 occur without signs or symptoms and are defined by the presence of pathogenic variants in the SNCA gene (stage 0), S alone (stage 1A), or S and D (stage 1B). The presence of clinical manifestations marks the transition to stage 2 and beyond. Stage 2 is characterised by subtle signs or symptoms but without functional impairment. Stages 2B-6 require both S and D and stage-specific increases in functional impairment. A biological definition of neuronal α-synuclein disease and an NSD-ISS research framework are essential to enable interventional trials at early disease stages. The NSD-ISS will evolve to include the incorporation of data-driven definitions of stage-specific functional anchors and additional biomarkers as they emerge and are validated. Presently, the NSD-ISS is intended for research use only; its application in the clinical setting is premature and inappropriate.
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Doença por Corpos de Lewy , Doença de Parkinson , Sinucleinopatias , Humanos , alfa-Sinucleína/genética , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Doença por Corpos de Lewy/diagnóstico , Sinucleinopatias/diagnóstico , Corpos de Lewy , SíndromeRESUMO
El objetivo de este estudio fue determinar la implementación del curso de ética dentro del currículo odontológico de las facultades pertenecientes a la Federación Internacional de Escuelas y Facultades de Odontología FIEFO, 2021. Investigación de tipo descriptivo, transversal y observacional, la población estuvo constituida por decanos y directores de la FIEFO que participaron en el seminario de Ética el 26 de febrero del 2021. A ellos se les envió, vía correo electrónico, el consentimiento informado y la encuesta. Los resultados de estudio mostraron que el 86,67 % de las universidades tienen el curso de ética de forma obligatoria; el 50 % de las universidades implementan el curso de ética de 1 a 2 horas por semana; con relación al año de dictado, se desarrolló en mayor porcentaje en el tercer año. Por último, se encontraron diferentes enfoques sobre el objetivo del curso, siendo estos los más frecuentes: "Formación del profesional para el desarrollo de una práctica ética"; "Comprensión y aplicación de la bioética" y "Formación Profesional con desarrollo de habilidades desde un enfoque ético".
The objective of this study was to determine the implementation of the ethics course within the dental curriculum of the faculties belonging to the International Federation of Schools and Faculties of Dentistry FIEFO, 2021. Descriptive, cross-sectional and observational research, the population consisted of deans and FIEFO directors who participated in the Ethics seminar on February 26, 2021. The informed consent and the survey were sent to them via email. The results of the study showed that 86.67 % of the universities have the ethics course mandatory; 50 % of the universities implement the ethics course from 1 to 2 hours per week; in relation to the year of dictation, it was developed in a higher percentage in the third year. Finally, different approaches were found on the objective of the course, these being the most frequent: "Professional training for the development of an ethical practice"; "Understanding and application of bioethics" and "Professional Training with skills development from an ethical approach".
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Dentre os órgãos linfoides encontram-se os linfonodos. Também conhecidos como nódulos linfáticos, os quais sãoconsiderados como filtros da linfa por serem ricos em linfócitos e outras células de defesa. Entre os fatores quecontribuem para o seu comprometimento temos a invasão de sua estrutura por células neoplásicas. A citologia constituio exame padrão ouro no diagnóstico sendo, a PAAF a técnica mais utilizada para a obtenção do material a ser analisado.Entretanto, alguns estudos questionam a sua utilização, devido à perda da arquitetura celular. A espectroscopia Ramanconfocal por meio da sua capacidade em utilizar as diferenças bioquímicas de tecidos e células vem se destacandocada vez mais neste tipo de diagnóstico. O estudo teve por objetivo identificar as principais características bioquímicasem linfonodos normais, comprometidos e lesão cervical utilizando a espectroscopia Raman confocal. Foram analisadas12 amostras de linfonodos normais e alterados de pacientes com indicação cirúrgica para linfadenectomia pelaespectroscopia seguida pela análise estatística de componentes principais (PCA) e análise de discriminante linear (LDA).Após as análises observou-se que a técnica utilizada conseguiu discriminar os tecidos com valores de especificidade,sensibilidade e acurácia de 83%. Portanto, a espectroscopia Raman confocal se mostrou uma importante ferramenta nacaracterização de linfonodos podendo futuramente auxiliar no diagnóstico de lesões linfonodais(AU)
Among the lymphoid organs there are lymph nodes,, which are considered as lymph filters because they are rich inlymphocytes and other defense cells. Among the factors that contribute to their impairment we note the invasion of itsstructure by neoplastic cells. Cytology is the gold-standard diagnostic test, and FNA is the technique most used to obtainthe material to be analyzed. However, some studies question its use, due to the loss of cellular architecture. ConfocalRaman spectroscopy, through its ability to utilize biochemical differences in tissues and cells, has been increasinglyprominent in this type of diagnosis. The study aimed to identify the main biochemical characteristics in normal andcompromised lymph nodes and cervical lesion using confocal Raman spectroscopy. We analyzed 12 normal andaltered lymph node samples from patients with medical indications for a lymphadenectomy by spectroscopy, followedby statistical analysis of the main components (PCA) and linear discriminant analysis (LDA). After the analysis, it wasobserved that this technique was able to discriminate the tissues with values of specificity, sensitivity and accuracy ofup to 83%. Therefore, confocal Raman spectroscopy has been shown to be an important tool in the characterization oflymph nodes, and may help in the diagnosis of lymph node lesions in the future(AU)
Assuntos
Humanos , Tecido Linfoide , Análise Espectral Raman , Linfoma , Análise Espectral Raman/métodos , Linfonodos , Metástase NeoplásicaRESUMO
Dentre os órgãos linfoides encontram-se os linfonodos. Também conhecidos como nódulos linfáticos, os quais são considerados como filtros da linfa por serem ricos em linfócitos e outras células de defesa. Entre os fatores que contribuem para o seu comprometimento temos a invasão de sua estrutura por células neoplásicas. A citologia constitui o exame padrão ouro no diagnóstico sendo, a PAAF a técnica mais utilizada para a obtenção do material a ser analisado. Entretanto, alguns estudos questionam a sua utilização, devido à perda da arquitetura celular. A espectroscopia Raman confocal por meio da sua capacidade em utilizar as diferenças bioquímicas de tecidos e células vem se destacando cada vez mais neste tipo de diagnóstico. O estudo teve por objetivo identificar as principais características bioquímicas em linfonodos normais, comprometidos e lesão cervical utilizando a espectroscopia Raman confocal. Foram analisadas 12 amostras de linfonodos normais e alterados de pacientes com indicação cirúrgica para linfadenectomia pela espectroscopia seguida pela análise estatística de componentes principais (PCA) e análise de discriminante linear (LDA). Após as análises observou-se que a técnica utilizada conseguiu discriminar os tecidos com valores de especificidade, sensibilidade e acurácia de 83%. Portanto, a espectroscopia Raman confocal se mostrou uma importante ferramenta na caracterização de linfonodos podendo futuramente auxiliar no diagnóstico de lesões linfonodais.
Among the lymphoid organs there are lymph nodes,, which are considered as lymph filters because they are rich in lymphocytes and other defense cells. Among the factors that contribute to their impairment we note the invasion of its structure by neoplastic cells. Cytology is the gold-standard diagnostic test, and FNA is the technique most used to obtain the material to be analyzed. However, some studies question its use, due to the loss of cellular architecture. Confocal Raman spectroscopy, through its ability to utilize biochemical differences in tissues and cells, has been increasingly prominent in this type of diagnosis. The study aimed to identify the main biochemical characteristics in normal and compromised lymph nodes and cervical lesion using confocal Raman spectroscopy. We analyzed 12 normal and altered lymph node samples from patients with medical indications for a lymphadenectomy by spectroscopy, followed by statistical analysis of the main components (PCA) and linear discriminant analysis (LDA). After the analysis, it was observed that this technique was able to discriminate the tissues with values of specificity, sensitivity and accuracy of up to 83%. Therefore, confocal Raman spectroscopy has been shown to be an important tool in the characterization of lymph nodes, and may help in the diagnosis of lymph node lesions in the future.
Assuntos
Humanos , Tecido Linfoide , Linfoma , Análise Espectral Raman , Linfonodos , Metástase Neoplásica , Análise Espectral Raman/métodosRESUMO
Background: Exercise may be a therapeutic tool for improving the functional capacity in patients with chronic kidney disease (CKD) who are on hemodialysis (HD). Aim: To determine the effects on muscle strength (MS), functional capacity (FC) and quality of life related to health (QOLRH) of a resistance training program in patients with CKD on HD. Patients and Methods: Thirteen CKD patients aged 38.8 ± 3 years, (7 men) on HD for more than one year participated in an exercise program twice a week during 8 weeks. At the beginning and at the end of the program, MS using a knee extension isometric strength test, FC using the six minutes walking test (6MWT) and QOLRH using the KDQOL CV-36 questionnaire were evaluated. Heart and respiratory rates, blood pressure, oxygen saturation and modified Borg scale were measured as control variables. Results: After training, there were significant improvements in MS in both legs; in the distance travelled during 6MWT and in the physical component summary score of the KDQOL-36. Furthermore, a significant decline in diastolic blood pressure was observed. All other control variables did not change significantly. Conclusions: Exercise training during eight weeks in CKD patients in HD resulted in significant improvements in muscle strength, walking capacity and in the physical component of a quality of life score for patients with CKD.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Qualidade de Vida , Insuficiência Renal Crônica/terapia , Terapia por Exercício/métodos , Força Muscular/fisiologia , Treinamento Resistido , Inquéritos e Questionários , Estudos Longitudinais , Diálise Renal , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/psicologiaRESUMO
El quiste del conducto nasopalatino es el más común de la cavidad oral, por lo general es asintomático y pocas veces se manifiesta hacia el exterior. Suele ser un hallazgo radiográfico y puede infectarse produciendo sintomatología. Existe mayor prevalencia en adultos entre 40 a 60 años de edad, varones y sin predominio racial. El tratamiento de esta lesión es quirúrgico y está indicado solo si muestra alguna manifestación clínica, como: dolor, movilidad dentaria y la expansión del quiste. Se reporta el caso de una paciente, de sexo femenino de 70 años, que presenta movilidad en piezas anteriores. Mediante la evaluación con tomografía computarizada Cone Beam, se observó una imagen radiolúcida en el maxilar superior, compatible con un quiste naso palatino, muy cercano a los ápices dentarios. Se realizaron las exodoncias de las piezas comprometidas con preservación del tejido óseo, mediante técnicas regenerativas. Posteriormente se colocaron implantes dentales en la zona...
The Nasopalatine duct cyst is the most common in oral cavity. In general is not symptomatic and in a few cases it goes extra osseous. Mostly it is found in an x-ray exam, if it goes under infection there is symptomatology. There is more prevalence in adults between 40 to 60 years old, males and without racial preponderance. The treatment is under surgery and is prescript only when there is a clinical manifestation, those manifestations could be: pain, tooth mobility and cyst expansion. The case of a patient, female, 70 years old who show tooth mobility is reported. Using the cone-beam computed tomography we found a radiolucent image compatiblewith a nasopalatine duct cyst, near to the dental apices. Extractions of pieces involved with preservation of bone tissue was performed by regenerative techniques. Subsequently dental implants were placed in the area...
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Humanos , Feminino , Idoso , Implantes Dentários , Cistos Ósseos , Regeneração Óssea , TomografiaRESUMO
Objetivo. Evaluar la capacidad de hidrocompatibilidad de las siliconas por condensación de consistencia liviana, de acuerdo al ángulo de contacto. Material y métodos. Se realizó un estudio descriptivo, comparativo con la finalidad de evaluar la capacidad de hidrocompatibilidad de tres siliconas por condensación para ello se diseñaron 3 cuerpos de prueba de forma rectangular de 1 cm de espesor y 10 cm de largo, utilizando moldes de aluminio fabricados para este fin. Se llenaron los moldes con diferentes marcas comerciales de silicona liviana por condensación (Orange wash, Speedex y lastic 90 Fine). Sobre la superficie de la silicona se depositó una gota de agua destilada de 10 uL. de volumen utilizando una micropipeta Boeco y se tomaron fotografías de esta a los 0, 10 y 30 segundos. La experiencia se realizó 10 veces en cada cuerpo de prueba, siempre en un área limpia, de forma que se obtuvieron 30 fotografías por cada marca de silicona. Posteriormente, las imágenes fueron procesadas en un software para medir el ángulo de contacto a cada lado de la gota de agua (tpsDig), por lo que finalmente se consiguieron 60 mediciones por cuerpo de prueba (20 por cada tiempo considerado). Para determinar la hidrocompatibilidad se realizó el análisis estadístico media aritmética y desviación estándar. Resultados. El análisis descriptivo de los datos mostró que la silicona por condensación de consistencia liviana Speedex mostró un mejor comportamiento respecto a la disminución del ángulo de contacto y humectabilidad de superficie con el paso del tiempo tanto a los 10 y 30 segundos, seguido por la silicona Orange wash. La silicona Lastic 90 Fine presentó una pobre hidrocompatibilidad ya que su ángulo de contacto permaneció inalterable a pesar del paso de tiempo. Conclusiones. Existen diferencias marcadas respecto a la hidrocompatibilidad de los diferentes materiales utilizados en este estudio. La silicona que presento mejor hidrocompatibilidad fue la Speedex ...
Objective.To evaluate the capacity of hidrocompatibility of the silicones by condensation of light consitency, according to the contact angle. Material and methods. A descriptive, comparative study was made with the purpose of evaluating the capacity of hidrocompatibility of three silicones by condensation, for this reason, 3 bodies of test of rectangular form with a thickness of 1 cm and a length of 10 cm were designed, using molds of aluminium made for this use. The molds were filled by different commercial brands of light silicone by condensation (Orange wash, Speedex and lastic 90 Fine). On the surface of the silicone a drop of distilled water of 10 uL of volume was deposited ,using a micropipette Boeco and photographies of this was one was taken at 0, 10 and 30 seconds. The experience was made 10 times in every body of test, always in a clean area, there were taken 30 photographies by every brand of silicone. Then, the images were processed in software to measure the contact angle to every side of the water drop (tpsDig); finally 60 measurements were obtained by body of test (20 in each time). To evaluate hydrocompatibility, there were made statistical analysis using arithmetic mean and standard deviation. Results. The descriptive analysis of the data showed that the silicone by light condensation Speedex had a better behavior with regard to the decrease of the contact angle and surface wettability with the time, from 10 to 30 seconds, followed by the silicone Orange wash. The silicone Lastic 90 Fine showed a poor hydrocompatibility and its contact angle remained without changes in spite of the time. Conclusions. There are differences with regard to the hydrocompatibility of the different materials used in this study. Silicone that shows a better hydrocompatibility was the brand Speedex while the brand Lastic 90 Fine showed worst results with regard to the contact angle.
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Condensação , Materiais Dentários , Silicones , Epidemiologia DescritivaRESUMO
La enfermedad periodontal es de carácter multifactorial. En este artículo de revisión mencionaré el tabaco como factor de riesgo. Numerosas investigaciones demuestran la relación entre fumar y enfermedad periodontal. Tanto estudios transversales como longitudinales nos dan suficiente evidencia de que fumar aumenta considerablemente el riesgo de la periodontitis. Fumar cigarrillos afecta la circulación, el sistema inmune y los mecanismos inflamatorios.
Periodontal disease is multifactorial in its nature. In this article I will focus on smoking as a risk factor. Numerous studies demonstrate the relationship between smoking and periodontal disease. Both, transversal and longitudinal studies provide us with sufficient evidence that smoking increases the risk of periodontitis. Cigarette smoking affects the circulation, the immune system and the inflammatory response.
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Humanos , Doenças Periodontais , Fatores de Risco , NicotianaRESUMO
Introducción: el presente estudio tuvo por objeto determinar el efecto de los hábitos bucales parafuncionales en el desarrollo de disfunción temporomandibular en individuos laxos y no laxos. Material y método: se evaluaron 216 niños de 10 y 11 años de edad, de ambos sexos, estudiantes del colegio 0014 Andrés Bello. Se les realizó el examen clínico para determinar el grado disfunción temporomandibular según los criterios de Helkimo. Seleccionamos a los pacientes disfuncionados (disfunción leve, moderada y severa) teniendo una muestra de 170 niños. A estos se les realizó el examen de laxitud articular que consistía en realizar las maniobras de Carter y Wilkinson modificadas por Beighton y además se determinó la presencia de hábitos bucales parafuncionales mediante la observación clínica y la entrevista. Los hábitos analizados fueron: Onicofagia, bruxismo, "juego mandibular" y mordedura de labio y/o carrillo. Resultados: nos muestran que existe relación estadísticamente significativa entre hábitos bucales parafuncionales y pacientes disfuncionados laxos, a diferencia de los pacientes disfuncionados no laxos. Conclusiones: el grado de disfunción temporomandibular leve y moderado se presenta con mayor frecuencia en individuos de 10 y 11 años. Así mismo, la prevalencia de la laxitud articular en individuos de 10 y 11 años se da más en las niñas que en los niños.
Introducción: the present study aim was determining the effect of parafunctional oral habits in the development of temporomandibular dysfunction in people lax and not lax. Material and method: we studied 216 children, aged 10 and 11 years, males and females, students of 0014 Andrés Bello Elementary School, they were examined for determinate the grade of temporomandibular dysfunction based in the Helkimos criterions. We selected the patients who are with dysfunction (low, moderate and strong) they were 170 children. This children were examined for determinate the grade of joint laxity based in made the Carter and Wilkinsons maneuvers, modified by Beighton and moreover we determined the present of parafunctional oral habits by the clinical observation and the interview. The habits we analyzed were: Bite fingernails, bruxism, "mandible play" and bite lips. Results: there is a significant, albeit weak, correlation between parafunctional oral habits and patients lax with dysfunction, difference of the patients not lax with dysfunction. Conclusions: low and moderate temporomandibular dysfunction grade presents with more frecuency in childs of 10 and 11 years old. Also, the prevalence of joint laxity in childs of 10 and 11 years affects more girls than boys.
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Humanos , Masculino , Criança , Feminino , Instabilidade Articular , Sistema Estomatognático , Síndrome da Disfunção da Articulação Temporomandibular , Estudos Prospectivos , Estudos Transversais , Estudos Observacionais como AssuntoRESUMO
The lipid composition of human placenta phospholipids, coming from 9 undernourished women that gave birth to low weight newborns and 9 well norished women, was analyzed using gas-liquid chromatography. Phospholipids of placentas coming from undernourished women, when compared to well nourished women, had significantly lower amounts of w-6 and w-3 fatty acids (40.1 ñ 1.5 vs 42.4 ñ 1.4 and 6.0 ñ 0.7 vs 7.1 ñ 1,3 per cent respectively). The calculated mean melting point was higher in placentas coming from undernourished women. In these women, the low content of polyunsaturated fatty acids and its replacement by short chain fatty acids was not able to balance the high mean melting points. The relative deficiency of essencial fatty acids, the low saturation index and the high mean melting point of undernourished women's placental phospholipids, may suggest a lower membrane fluidity and a subnormal essencial fatty acid content of fetal organs, that are essencial for normal growth and development
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Humanos , Feminino , Gravidez , Recém-Nascido , Placenta/metabolismo , Doenças Placentárias/etiologia , Distúrbios Nutricionais/complicações , Fosfolipídeos/análise , Lipídeos/sangue , Placenta/fisiopatologia , Placenta/química , Gorduras na Dieta/análise , Estudos de Casos e Controles , Estado Nutricional , Ácidos Graxos Essenciais/deficiênciaRESUMO
Alzheimer's disease is a progressive neurodegenerative disorder that affects a significant percentage of elderly individuals. Degenerative nerve cells express atypical proteins, and amyloid is deposited. The hallmark event of Alzheimer's disease is the deposition of amyloid as insoluble fibrous masses in extracellular neuritic plaques and around the walls of cerebral blood vessels. This review will focus on the advances on the knowledge of Alzheimer's amyloid, because it is becoming increasingly clear that the deposition of amyloid on neuritic plaques in the brain represents the earliest and most characteristic pathological feature of Alzheimer's disease. The main component of amyloid is a 4.2-4.5 KDa hydrophobic peptide, named amyloid beta-peptide, that is codified in chromosome 21 as part of a much larger precursor protein. The study of the mechanism by which the amyloid beta-peptide arises from the amyloid precursor protein is very important in order to understand the biological basis of amyloid deposition and its role in Alzheimer's disease
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Animais , Humanos , Doença de Alzheimer/genética , Amiloide/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Amiloide/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Biologia Molecular/métodos , Fatores de Crescimento Neural/metabolismo , Neurotoxinas/metabolismo , Precursores de Proteínas/metabolismoRESUMO
Se investigó el efecto de la restricción dietética y de la deficiencia de ácidos grasos durante la preñez, en la composición lípida y fosfolipídica de la placenta de ratas a los 21 días post-concepción. El estudio se llevó a cabo en ratas hembra vírgenes de la cepa Wistar con un peso promedio de 130 g, las que se dividieron en tres grupos similares. Cada grupo fue alimentado desde antes y durante la preñez de la siguiente manera: el Grupo Control (C) consumió, ad libitum, una dieta con 25% de la caseína; el Grupo Desnutrido (D) se alimentó con el 50% (g/100 g rata) de la cantidad consumida de la misma dieta del grupo C, y al Grupo Desnutrido Deficiente (DD) se le asignó la misma cantidad consumida por el grupo D, pero de una dieta deficiente en AGE. A los 21 días de edad gestacional, las ratas preñadas de los tres grupos, fueron sacrificadas y se les extrajeron los fetos y las placentas, los cuales se pesaron, liofilizando las placentas. La restricción de una dieta balanceada disminuyó significativamente el contenido de fosfolípidos (P < 0.05); la deficiencia severa de AGE sobreimpuesta a la restricción dietética alteró, además, el perfil de los ácidos grasos incorporados a los fosfolípidos, disminuyendo los ácidos grasos de las series n3 y n6 y no aumentando el eicosatrienoico. Ajeno a ello, retuvo los triglicéridos significativamente. Ambos tipos de restricción redujeron el crecimiento fetal; el Grupo DD no modificó el peso placentario, pero sí disminuyó casi a la mitad el número de crías de la camada
Assuntos
Gravidez , Ratos , Animais , Feminino , Ácidos Graxos Essenciais/deficiência , Fosfolipídeos/análise , Placenta/análise , Deficiência de ProteínaRESUMO
Se estuda el efecto de la restricción al 50% de una dieta balanceada con 25% de caseína desde antes y durante la gestación, sobre la composición lipídica de la placenta a los 21 días post-concepción en ratas. Este tipo de alteración nutricional disminuye significativamente el contenido total de fosfolípidos y la distribución de las cabezas polares de los mismos, elevándose significativamente la cardiolipina y bajando el contenido de fosfatidilserina; la composición de los ácidos grasos totales y de los ácidos grasos incorporados a los fosfolípidos se altera, evidenciándo-se un aumento de los ácidos grasos saturados y por lo tanto una menor relación insaturados/saturados; los fosfolípidos de la placenta muestran una acumulación de ácidos grasos esenciales y de sus derivados altamente insaturados. Se discuten estos resultados en relación a la función de la placenta y su rol en el crecimiento fetal