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BACKGROUND: The Cavalieri estimator is used for volume measurement of brain and brain regions. Derived from this estimator is the Area Fraction Fractionator (AFF), used for efficient area and number estimations of small 2D elements, such as axons in cross-sectioned nerves. However, to our knowledge, the AFF has not been combined with serial sectioning analysis to measure the volume of small-size nervous structures. NEW METHOD: Using the nigrostriatal dopaminergic system as an illustrative case, we describe a protocol based on Cavalieri's principle and AFF to estimate the volume of its somatic, nuclear, dendritic, axonal and axon terminal cellular compartments in the adult mouse. The protocol consists of (1) systematic random sampling of sites within and across sections in regions of interest (substantia nigra, the nigrostriatal tract, caudate-putamen), (2) confocal image acquisition of sites, (3) marking of cellular domains using Cavalieri's 2D point-counting grids, and 4) determination of compartments' total volume using the estimated area of each compartment, and between-sections distance. RESULTS: The volume of the nigrostriatal system per hemisphere is â¼0.38â¯mm3, with â¼5â¯% corresponding to perikarya and cell nuclei, â¼10â¯% to neuropil/dendrites, and â¼85â¯% to axons and varicosities. COMPARISON WITH EXISTING METHODS: In contrast to other methods to measure volume of discrete objects, such as the optical nucleator or 3D reconstructions, it stands out for its versatility and ease of use. CONCLUSIONS: The use of a simple quantitative, unbiased approach to assess the global state of a system may allow quantification of compartment-specific changes that may accompany neurodegenerative processes.
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Vascular fibrosis, characterized by increased Type I collagen expression, significantly contributes to vascular remodeling. Our previous studies show that disrupting the expression of SM22α (aka SM22, Tagln) induces extensive vascular remodeling following arterial injury, involving oxidative stress, inflammation, and chondrogenesis within the vessel wall. This study aims to investigate the molecular mechanisms underlying the transcription of Col1a2, a key fibrotic extracellular matrix marker. We observed upregulation of COL1A2 in the arterial wall of Sm22-/- mice following carotid injury. Bioinformatics and molecular analyses reveal that Col1a2 transcription depends on a CArG box in the promoter, activated synergistically by SRF and SMAD3. Notably, we detected enhanced nuclear translocation of both SRF and SMAD3 in the smooth muscle cells of the injured carotid artery in Sm22-/- mice. These findings demonstrate that SM22 deficiency regulates vascular fibrosis through the interaction of SRF and the SMAD3-mediated canonical TGF-ß1 signal pathway, suggesting SM22α as a potential therapeutic target for preventing vascular fibrosis.
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This article reviews the evidence regarding the safety and efficacy of intra-cytoplasmic sperm injection (ICSI). It provides evidence-based clinical and laboratory guidelines and recommendations for use of ICSI within an assisted reproductive technology (ART) service. The guidelines address the evidence for the use of ICSI rather than conventional IVF (cIVF); the use of ART techniques supplementary to ICSI; and risks associated with ICSI. This article is not intended to be the only approved standard of practice or to dictate an exclusive course of treatment. Other plans of management may be appropriate, taking into account the needs and medical history of the patient, available resources, and institutional or clinical practice limitations.
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The catecholaminergic system has received much attention based on its regulatory role in a wide range of brain functions and its relevance in aging and neurodegenerative diseases. In the present study, we analyzed the neuroanatomical distribution of catecholaminergic neurons based on tyrosine hydroxylase (TH) immunoreactivity in the brain of adult Nothobranchius furzeri. In the telencephalon, numerous TH+ neurons were observed in the olfactory bulbs and the ventral telencephalic area, arranged as strips extending through the rostrocaudal axis. We found the largest TH+ groups in the diencephalon at the preoptic region level, the ventral thalamus, the pretectal region, the posterior tuberculum, and the caudal hypothalamus. In the dorsal mesencephalic tegmentum, we identified a particular catecholaminergic group. The rostral rhombencephalon housed TH+ cells in the locus coeruleus and the medulla oblongata, distributing in a region dorsal to the inferior reticular formation, the vagal lobe, and the area postrema. Finally, scattered TH+ neurons were present in the ventral spinal cord and the retina. From a comparative perspective, the overall organization of catecholaminergic neurons is consistent with the general pattern reported for other teleosts. However, N. furzeri shows some particular features, including the presence of catecholaminergic cells in the midbrain. This work provides a detailed neuroanatomical map of the catecholaminergic system of N. furzeri, a powerful aging model, also contributing to the phylogenetic understanding of one of the most ancient neurochemical systems.
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In the adult hippocampus, new neurons are generated in the dentate gyrus. The Wnt signaling pathway regulates this process, but little is known about the endogenous Wnt ligands involved. We investigated the role of Wnt5a on adult hippocampal neurogenesis. Wnt5a regulates neuronal morphogenesis during embryonic development, and maintains dendritic architecture of pyramidal neurons in the adult hippocampus. Here, we determined that Wnt5a knockdown in the mouse dentate gyrus by lentivirus-mediated shRNA impaired neuronal differentiation of progenitor cells, and reduced dendritic development of adult-born neurons. In cultured adult hippocampal progenitors (AHPs), Wnt5a knockdown reduced neuronal differentiation and morphological development of AHP-derived neurons, whereas treatment with Wnt5a had the opposite effect. Interestingly, no changes in astrocytic differentiation were observed in vivo or in vitro, suggesting that Wnt5a does not affect fate-commitment. By using specific inhibitors, we determined that Wnt5a signals through CaMKII to induce neurogenesis, and promotes dendritic development of newborn neurons through activating Wnt/JNK and Wnt/CaMKII signaling. Our results indicate Wnt5a as a niche factor in the adult hippocampus that promotes neuronal differentiation and development through activation of noncanonical Wnt signaling pathways.
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Hipocampo/metabolismo , Neuronas/metabolismo , Vía de Señalización Wnt/genética , Proteína Wnt-5a/metabolismo , Animales , Diferenciación Celular , Femenino , Ratones , TransfecciónRESUMEN
Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The disease is caused by the proto-bacteria Candidatus Liberibacter asiaticus and transmitted by the Asian citrus psyllid Diaphorina citri. HLB symptoms are slow to appear while the tree continues to be a source of inoculum. Monitoring tree health and rapid detection of HLB is critical for sustainable citrus production. Currently, scientists are working on developing new techniques for pre-symptomatic detection of HLB, as there is no available method for real-time assessment of tree health. In this study, we demonstrate the rapid and efficient discrimination between healthy and HLB-affected citrus by laser-induced breakdown spectroscopy combined with chemometric analysis. Healthy and HLB-affected trees were differentiated with a high degree of precision. The novelty of this method lies in the fingerprinting of healthy and diseased plants based on their organic and inorganic constituents, and the use of a multi-pulse laser coupled with a microscope to take spectra of the plant phloem.
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Citrus/microbiología , Floema/química , Enfermedades de las Plantas/microbiología , Rhizobiaceae/aislamiento & purificación , Análisis Espectral/métodos , Técnicas BacteriológicasRESUMEN
The axon initial segment (AIS) is the site of initiation of action potentials and influences action potential waveform, firing pattern, and rate. In view of the fundamental aspects of motor function and behavior that depend on the firing of substantia nigra pars compacta (SNc) dopaminergic neurons, we identified and characterized their AIS in the mouse. Immunostaining for tyrosine hydroxylase (TH), sodium channels (Nav ) and ankyrin-G (Ank-G) was used to visualize the AIS of dopaminergic neurons. Reconstructions of sampled AIS of dopaminergic neurons revealed variable lengths (12-60 µm) and diameters (0.2-0.8 µm), and an average of 50% reduction in diameter between their widest and thinnest parts. Ultrastructural analysis revealed submembranous localization of Ank-G at nodes of Ranvier and AIS. Serial ultrathin section analysis and 3D reconstructions revealed that Ank-G colocalized with TH only at the AIS. Few cases of synaptic innervation of the AIS of dopaminergic neurons were observed. mRNA in situ hybridization of brain-specific Nav subunits revealed the expression of Nav 1.2 by most SNc neurons and a small proportion expressing Nav 1.6. The presence of sodium channels, along with the submembranous location of Ank-G is consistent with the role of AIS in action potential generation. Differences in the size of the AIS likely underlie differences in firing pattern, while the tapering diameter of AIS may define a trigger zone for action potentials. Finally, the conspicuous expression of Nav 1.2 by the majority of dopaminergic neurons may explain their high threshold for firing and their low discharge rate.
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Segmento Inicial del Axón/fisiología , Neuronas Dopaminérgicas/citología , Sustancia Negra/citología , Potenciales de Acción/fisiología , Animales , Ancirinas/metabolismo , Ancirinas/ultraestructura , Segmento Inicial del Axón/ultraestructura , Expresión Génica/fisiología , Imagenología Tridimensional , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Microscopía Inmunoelectrónica , Canal de Sodio Activado por Voltaje NAV1.2/genética , Canal de Sodio Activado por Voltaje NAV1.2/metabolismo , Canal de Sodio Activado por Voltaje NAV1.2/ultraestructura , Canal de Sodio Activado por Voltaje NAV1.6/genética , Canal de Sodio Activado por Voltaje NAV1.6/metabolismo , Canal de Sodio Activado por Voltaje NAV1.6/ultraestructura , Neuroimagen , ARN Mensajero/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Tirosina 3-Monooxigenasa/ultraestructuraRESUMEN
Neurons in the trigeminal (Mo5), facial (Mo7), ambiguus (Amb), and hypoglossal (Mo12) motor nuclei innervate jaw, facial, pharynx/larynx/esophagus, and tongue muscles, respectively. They are essential for movements subserving feeding, exploration of the environment, and social communication. These neurons are largely controlled by sensory afferents and premotor neurons of the reticular formation, where central pattern generator circuits controlling orofacial movements are located. To provide a description of the orofacial nuclei of the adult mouse and to ascertain the influence of excitatory and inhibitory afferents upon them, we used stereology to estimate the number of motoneurons as well as of varicosities immunopositive for glutamate (VGluT1+, VGluT2+) and GABA/glycine (known as VIAAT+ or VGAT+) vesicular transporters in the Mo5, Mo7, Amb, and Mo12. Mo5, Mo7, Amb, and Mo12 contain â¼1,000, â¼3,000, â¼600, and â¼1,700 cells, respectively. VGluT1+, VGluT2+, and VIAAT+ varicosities respectively represent: 28%, 41%, and 31% in Mo5; 2%, 49%, and 49% in Mo7; 12%, 42%, and 46% in Amb; and 4%, 54%, and 42% in Mo12. The Mo5 jaw-closing subdivision shows the highest VGluT1+ innervation. Noticeably, the VGluT2+ and VIAAT+ varicosity density in Mo7 is 5-fold higher than in Mo5 and 10-fold higher than in Amb and Mo12. The high density of terminals in Mo7 likely reflects the convergence and integration of numerous inputs to motoneurons subserving the wide range of complex behaviors to which this nucleus contributes. Also, somatic versus neuropil location of varicosities suggests that most of these afferents are integrated in the dendritic trees of Mo7 neurons.
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Cara/inervación , Núcleo Motor del Nervio Facial/citología , Bulbo Raquídeo/citología , Neuronas Motoras/citología , Boca/inervación , Núcleo Motor del Nervio Trigémino/citología , Animales , Recuento de Células , Núcleo Motor del Nervio Facial/metabolismo , Ácido Glutámico/metabolismo , Glicina/metabolismo , Nervio Hipogloso/citología , Nervio Hipogloso/metabolismo , Inmunohistoquímica , Masculino , Bulbo Raquídeo/metabolismo , Ratones Endogámicos C57BL , Neuronas Motoras/metabolismo , Inhibición Neural/fisiología , Tamaño de los Órganos , Núcleo Motor del Nervio Trigémino/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Antecedentes:En Honduras son escasas las publicaciones sobre estilos de vida saludable, la OMS considera las enfermedades crónicas no transmisibles la principal causa de mortalidad y discapacidad mundial. Muchas de estas enfermedades tienen su origen en la adolescencia por la adopción de estilos de vida no saludables y conductas de riesgo. Se propuso determinar estilos de vida y factores asociados a estas enfermedades en grupo de estudiantes.Población y Método: se efectuó estudio descriptivo transversal en 240 estudiantes de Institutos de secundaria del casco urbano-rural de municipios de La Esperanza-Intibucá, de junio 2012 a junio 2013. Se aplicó encuesta que recolectaba información sociodemográfica, estilos de vida, antecedentes personal y familiares patológicos. Se midieron signos vitales y antropometría. Resultados:162/240 (77.5%) de estudiantes tenían de 12 a 17 años, 33.3%(80/240) de jóvenes entre 12 y 24 años tuvieron sexo en el último año, de los cuales 43.5%(35/80) tuvieron más de 1 pareja y 18%(15/80) no utilizo método anticonceptivo. En relación a estilos de vida, 20.4%(49/240) caminan menos de 30 minutos/día, 14.5%(10/69) fuman actualmente y 12.1%(29/240) están en sobrepeso. Los antecedentes familiares más frecuentes fueron hipertensión arterial y diabetes mellitus, 40.4%(97/240) y 19.6%(47/240) respectivamente.Discusión: Las enfermedades crónicas no transmisibles son en la actualidad una epidemia, identificar e intervenir sobre los factores de riesgo prevenibles que las condicionan, puede disminuir la carga que implican para los sistemas de salud. En este grupo de estudiantes, especialmente adolescentes, se encontró que tienen factores de riesgo en estilo de vida que condicionan aparición de enfermedades crónicas no transmisibles e infecciones de transmisión sexual...
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Humanos , Masculino , Adolescente , Femenino , Adulto Joven , Estilo de Vida Saludable , Estilo de Vida , Conducta Sedentaria , Enfermedades de Transmisión Sexual/complicaciones , Salud Rural/economíaRESUMEN
Objetivo: Comparar los valores obtenidos con sonda milimetrada y compás de punta seca como instrumentos de medida en la aplicación del Índice Estético Dental (DAI). Metodología: En 50 pacientes mayores de 12 años con dentición permanente, del Hospital Odontológico de la Facultad de Odontología de la Universidad Nacional del Nordeste (UNNE), se midieron las variables que componen el DAI, alternando ambos instrumentos de medición y se calculó el DAI. Resultados: En un 86 % de los casos ambos instrumentos arrojaron valores idénticos para las variables del DAI y en el 14 % restante las variaciones no superaron el mm. La correlación entre la puntuación final del DAI, midiendo las variables con sonda milimetrada y con compás de punta seca, fue estadísticamente significativa (r= 0,999). Conclusión: Las variaciones entre las medidas no influyeron en la puntuación final del índice lo que valida a la sonda milimetrada como instrumento de registro para el cálculo del DAI.
Objective: Compare the values obtained with calibrated probe and with drypoint compass as measuring instrument in implementing the Dental Aesthetic Index (DAI). Methodology: In 50 patients over 12 years with permanent dentition from ofDental Hospital, Faculty of Dentistry UNNE,were measured the variables that built the DAI, alternating both measuring instruments and estimated the DAI. Results: In 86% of cases both instruments yielded identical values for the DAI variables and the remaining 14% did not exceed one mm. The correlation between the final score of the DAI, measuring variables with calibrated probe and drypoint compass, was statistically significant (r = 0.999). Conclusions: Variations between measures not influence the final score of the indexvalidates the calibrated probe as a tool of registration for calculating the DAI.
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Instrumentos Dentales , Estética Dental , Maloclusión , Ortodoncia CorrectivaRESUMEN
Environmental metal pollution is one of the major problems faced by humankind. This type of pollution affects aquatic systems (estuaries, coastal lagoons, etc.), which are very dynamic systems, therefore making the study of the effects on the organisms that inhabit them an essential issue. In this study, the capacity of metal regulation by decapod crustacean Penaeus vannamei juveniles was determined. The effects of zinc, lead, and cadmium were tested individually and as a metal mixture exposure to determine possible synergism. The results showed that juvenile shrimps were capable of regulating zinc and lead, whereas cadmium was accumulated without any excretion, at least within the concentrations studied. It was also proved that under the estuarine conditions tested here, P. vannamei juveniles showed capacity to act as a bioindicator for cadmium.
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Cadmio/farmacocinética , Plomo/farmacocinética , Penaeidae/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Zinc/farmacocinética , Animales , Biomarcadores , Carga Corporal (Radioterapia) , Cadmio/análisis , Cadmio/toxicidad , Sinergismo Farmacológico , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Estuarios , Plomo/análisis , Plomo/toxicidad , Tasa de Depuración Metabólica , México , Concentración Osmolar , Océano Pacífico , Penaeidae/química , Penaeidae/efectos de los fármacos , Penaeidae/crecimiento & desarrollo , Espectrofotometría Atómica , Factores de Tiempo , Distribución Tisular , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Zinc/análisis , Zinc/toxicidadRESUMEN
Se estudiaron los expedientes de 14 defunciones quirúrgicas de una serie de 176 pacientes valorados con ASA 3 a 5 (riesgo elevado), sometidos a diferentes procedimientos quirúrgicos, del 1o. de julio al 30 de septiembre de 1991. Se analizaron los errores de manejo y se determinaron los factores que desencadenaron la muerte. La patología del paciente fue la principal causa de muerte. Predominó el error en el criterio médico de decisión quirúrgica