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1.
Rev. cient. odontol ; 9(1): e43, ene.-mar. 2021. ilus, tab
Article in Spanish | LILACS, LIPECS | ID: biblio-1254247

ABSTRACT

Objetivo: El propósito del presente estudio fue evaluar comparativamente las características de porosidad entre el cemento Portland, MTA Angelus® y Biodentine Septodont®, observados con un microscopio electrónico de barrido. Materiales y métodos: Se prepararon los cementos según las indicaciones del fabricante y se empaquetaron en tubos cilíndricos de polietileno con un diámetro interno de 10 mm y una altura de 5 mm. Se analizó la porosidad de las muestras mediante el microscopio electrónico de barrido. El análisis estadístico se realizó utilizando la prueba Kruskal-Wallis. El nivel de significancia se estableció en 0,05 Resultados: Se observó la descripción de la media de los valores del diámetro de los poros, y el tamaño mayor correspondió al cemento Portland (11,07). Existen diferencias significativas entre las medias del diámetro de los poros con un p = 0,05. Se identificó que el MTA Angelus® tiene la mayor cantidad de poros, le sigue el Biodentine Septodont® y, por último, el Portland. Se comparó la cantidad de poros entre los tres cementos y no se encontraron diferencias significativas, con un p = 0,09. Conclusión: Los análisis realizados en los cementos endodónticos dieron como resultado que el cemento Portland tiene mayor diámetro de poro a diferencia de los otros dos, lo cual implica que tanto el Biodentine Septodont® como el MTA Angelus® tienen mejores propiedades de resistencia y permeabilidad para evitar la microfiltración, y por tanto son mejores para la solución de casos clínicos. (AU)


Objective: The purpose of this study was to compare the porosity characteristics of Portland cement, mineral trioxide aggregate (MTA) Angelus® and Biodentine Septodont® by scanning electron microscopy. Materials and Methods: Cements were prepared according to the manufacturer's instructions and packed in cylindrical polyethylene tubes with an internal diameter of 10 mm and a height of 5 mm. The porosity of the samples was analyzed using scanning electron microscopy. Statistical analyses were performed using the Kruskall Wallis test. The level of significance was established at 0.05. Results: The largest size mean diameter valus was found with Portland cement (11.07). There were significant differences between the mean pore diameters (p = 0.05). MTA Angelus® had the largest number of pores, followed by Biodentine Septodont®, and finally, Portland. There were no significant differences in the pores of the three cements (p = 0.09). Conclusion: The results of this comparative analysis of endodontic cements showed that Portland cement has a larger pore diameter than MTA Angelus® and Biodentine Septodont®, demonstrating that these latter two cements present better resistance and permeability properties, and thereby prevent microleakage. (AU)


Subject(s)
Microscopy, Electron , Porosity , Dental Cements , Epidemiology, Descriptive , Cross-Sectional Studies
2.
Frontiers of Medicine ; (4): 933-937, 2021.
Article in English | WPRIM | ID: wpr-922509

ABSTRACT

Neurofibromatosis (NF) is a genetic disease in which the lungs are rarely involved. However, in NF cases with lung involvement, chest computed tomography may show bilateral basal reticulations, apical bullae, and cysts without bronchiectasis. Herein, we report a patient diagnosed with NF on the basis of the results of genetic testing who presented with early-onset wet cough and bronchiectasis. Considering the differential diagnosis of bronchiectasis combined with his early-onset wet cough, sinusitis, and sperm quality decline, we considered the possibility of primary ciliary dyskinesia (PCD). Further electron microscopy analysis of cilia and identification of homozygous mutations in the RSPH4A gene confirmed the diagnosis of PCD. Therefore, for patients with NF, when an image change exists in the lungs that does not correspond to NF, the possibility of other diagnoses, including PCD, must be considered.


Subject(s)
Cilia , Humans , Kartagener Syndrome/genetics , Microscopy, Electron , Mutation , Neurofibromatosis 1/genetics
3.
Braz. arch. biol. technol ; 64: e21200397, 2021. tab, graf
Article in English | LILACS | ID: biblio-1285557

ABSTRACT

HIGHLIGHTS Brachiaria brizantha proved to be a promising biomass for ethanol production. Fermentation was not impaired by the inhibitors furfural and hydroxymethylfurfural.


Abstract Different lignocellulosic biomasses are found worldwide and each country has its own important industrial crop that can be converted into high-value products, such as ethanol. Therefore, evaluation of new biomasses to be used in biorefineries is important to decrease the dependence on non-renewable resources and to guarantee sustainable development. This work evaluated Brachiaria brizantha, a grass commonly used as animal forage, and the standard biomass for 2G-ethanol, sugarcane bagasse. The chemical compositions of both biomasses were determined and different times and temperature of acid pretreatment were tested. Morphological analysis via scanning electron microscopy showed more deconstructed fibers after harsher biomass pretreatments. Simultaneous saccharification and fermentation of pretreated Brachiaria brizantha presented higher efficiency than when using sugarcane bagasse as the carbon source. A biomass conversion of 46 % was achieved when Brachiaria brizantha grass was pretreated with 2% sulfuric acid for 60 minutes. Moreover, fermentation was not impaired by the inhibitors furfural and hydroxymethylfurfural. It was concluded that Brachiaria brizantha is a promising biomass for ethanol production.


Subject(s)
Biomass , Brachiaria/chemistry , Saccharum/chemistry , Ethanol , Microscopy, Electron/instrumentation
4.
Int. j. morphol ; 38(6): 1786-1796, Dec. 2020. graf
Article in English | LILACS | ID: biblio-1134512

ABSTRACT

SUMMARY: Bisphenol A (BPA) is an industrial chemical widely used to make polycarbonate plastics for packaging and epoxy resins. This study sought to examine how selenium (Se) affects BPA toxicity in terms of albino rats' histological structure, antioxidant enzymes and reproductive organs (seminiferous tubules). Twenty-four adult male rats were divided into four experimental groups: Group 1: Control; Group 2: Orally administered BPA; Group 3: Orally administered sodium selenite; Group 4: Treated daily with BPA followed by selenium (Se). All experiment done for 4 weeks. BPA exposure caused changes in the testicular histological structure, which consists apoptosis, and led to changes in several biochemical markers: Malondialdehyde, catalase, superoxide dismutase, and glutathione peroxidase. However, these BPA side effects may be ameliorated in rats treated with BPA-plus-Se. These protective effects of Se may attributable to its ability to remove potentially damaging oxidizing agents in living organisms. The results may confirm that Se countered the oxidant effects and increased the BPA-induced stress response in rats. So, Se promotes the healthy growth and development of mammals by protecting them from oxidative stress. As human are greatly exposed to BPA and it can accumulate in tissues, there is concern about human reproductive functions particularly for occupational workers exposed usually to greater levels of BPA. Thus, the use of BPA in multiple industries must be restricted and the inaccurate usage of plastic containers should be avoided to decrease the health hazards. Administration of Se may protect against the adverse effects of BPA on reproductive functions and structures.


RESUMEN: El bisfenol A (BPA) es un químico industrial ampliamente utilizado para fabricar plásticos de policarbonato para envases y resinas epoxi. Este estudio examinó el efecto de selenio (Se) en la toxicidad del BPA en términos de la estructura histológica, enzimas antioxidantes y los órganos reproductivos (túbulos seminíferos) de ratas albinas. Se dividieron veinticuatro ratas macho adultas en cuatro grupos experimentales: Grupo 1: control; Grupo 2: BPA administrado por vía oral; Grupo 3: BPA administrado por vía oral para; Grupo 4: tratado diariamente con BPA seguido de selenio (Se). El experimento se realizó durante cuatro semanas y se observó que la exposición al BPA provocó cambios en la estructura histológica testicular, incluyendo apoptosis, y alteraciones en varios marcadores bioquímicos:malondialdehído, catalasa, superóxido dismutasa y glutatión peroxidasa. Sin embargo, estos efectos secundarios del BPA pueden mejorar en ratas tratadas con BPA-plus-Se. Estos efectos protectores del Se pueden ser atribuidos a la capacidad de eliminar agentes oxidantes potencialmente dañinos en organismos vivos. Los resultados indicaron que se contrarrestaron los efectos oxidantes y aumentó la respuesta al estrés inducido por BPA en ratas, y favorece el crecimiento y desarrollo en los mamíferos al protegerlos del estrés oxidativo. Debido a la exposición al BPA en el ser humano, se puede acumular en los tejidos, por lo que existe una preocupación por el daño a las funciones reproductivas en particular de los trabajadores que generalmente están expuestos a niveles más altos de BPA. Por lo tanto, se debe restringir el uso de BPA en las industrias y evitar el uso incorrecto de envases de plástico para así disminuir los riesgos para la salud. La administración correcta de Se puede proteger contra los efectos adversos del BPA en las funciones y estructuras reproductivas.


Subject(s)
Animals , Male , Rats , Phenols/toxicity , Selenium/pharmacology , Testis/drug effects , Benzhydryl Compounds/toxicity , Antioxidants/pharmacology , Phenols/administration & dosage , Superoxide Dismutase/drug effects , Testis/pathology , Benzhydryl Compounds/administration & dosage , Microscopy, Electron , Biomarkers , Catalase/drug effects , Administration, Oral , Apoptosis/drug effects , Oxidative Stress , Glutathione Peroxidase/drug effects
5.
Educ. med. super ; 34(2): e2057, abr.-jun. 2020.
Article in Spanish | LILACS, CUMED | ID: biblio-1124692

ABSTRACT

Introducción: Tradicionalmente, las clases prácticas con microscopios ópticos y láminas histológicas han sido el método principal para la enseñanza de la anatomía microscópica a los estudiantes de medicina. En este artículo se propone un cambio de paradigma. Objetivo: Ofrecer argumentos que propicien el debate sobre la conveniencia de enseñar anatomía microscópica a estudiantes de medicina prescindiendo de microscopios ópticos, láminas histológicas y clases prácticas en laboratorios de microscopía. Objetivo: Revisar Discutir los argumentos que avalaen la conveniencia de enseñar anatomía microscópica a estudiantes de medicina sin microscopios ópticos, láminas histológicas ni clases prácticas en laboratorios de microscopía. Desarrollo: Se propone otorgar un lugar protagónico a los dispositivos móviles, a través de los cuales el estudiante podrá gestionar su aprendizaje e interactuar con los medios de enseñanza y el profesor. Las imágenes digitales de preparaciones histológicas que representen diferentes métodos de estudio y microscopios (microscopía óptica, microscopía electrónica, inmunofluorescencia, etcétera), serán esenciales para el aprendizaje. Una actividad docente tipo seminario y no las clases prácticas tradicionales con microscopios ópticos y láminas histológicas resultaría la forma docente más adecuada; de este modo se propiciarían el intercambio y el debate, teniendo como base imágenes digitales que serán proyectadas en una pantalla para favorecer la explicación y la discusión de los contenidos. Se ofrecen 10 argumentos que respaldan la racionalidad de la propuesta. Conclusiones: Los argumentos a favor de enseñar histología sin con microscopios ópticos, láminas histológicas y prácticas en el laboratorio de microscopía constituyen han constituido la base para la enseñanza de sus contenidos durante años, pero el desarrollo de las TIC pudiera hacerlos innecesarios. Este cambio de paradigma debe ser sometido primero a pruebas empíricas y a un debate teórico(AU)


Introduction: Traditionally, hands-on classes with optical microscopes and histological laminae have been the primary method for teaching Microscopic Anatomy to medical students. In this article, we proposed a paradigm shift. Objective: To discuss review the foundations that support the convenience of teaching Microscopic Anatomy to medical students without optical microscopes, histological laminae, or hands-on classes in microscopy laboratories. Development: It is proposed to give a leading role to mobile devices, through which students can manage their learning and interact with the teaching media and with the teacher. Digital images of histological preparations representing different study methods and microscopes (optical microscopy, electron microscopy, immunofluorescence, etc.) will be essential for learning. A seminar-type teaching activity and not the traditional hands-on classes with optical microscopes and histological laminae would be the most suitable teaching form. In this way, exchange and debate would be fostered, based on digital images that will be projected on a screen in order to favor the explanation and discussion of the contents. Ten arguments are offered to support the rationality of the proposal. Conclusions: The arguments in favor of teaching Histology using optical microscopes, histological laminae, and microscopy laboratory practices have been the basis for teaching its contents in every year, but the development of information and communication technologies could make them unnecessary. This paradigm shift must first undergo empirical testing and theoretical debate(AU)


Subject(s)
Humans , Students, Medical , Microscopy, Electron , Information Technology , Anatomy , Learning
6.
Int. j. morphol ; 38(2): 305-308, abr. 2020. tab, graf
Article in English | LILACS | ID: biblio-1056439

ABSTRACT

Fixation is one of the processes in preparing histology and pathology. The common material for fixation is buffered formalin including paraformaldehyde. However, the effect of the damaged cells, which is fixed for a long time, causes the research for other fixation materials to become necessary. In addition, paraformaldehyde is also harmful to human body and natural environment. Ethanol is one of the alternative fixation materials, which has been used for two hundred years. It has been used for many purposes, both in routine staining and immunohistochemistry. Nonetheless, no research confirms its effect on the electron microscope. The authors studied the effect of 50 % of ethanol on the cell membrane, organelles, and nucleus of Purkinje cells (Neuron purkinjense) observed on a light microscope and Transmitted Electron Microscope (TEM). Then it was compared to buffered formalin. In the light microscope, it shows that both of fixations have no different effects of the morphology of the cell membrane, cytoplasm, the nucleus of Purkinje cells and the neutrophils. We assume that our 50 % of ethanol concentration is almost the same as BF 10 % in the ability of hardening tissue and color absorption based on the previous study. In TEM, the structure of the cell membrane, organelles, and cytoplasm of Purkinje cell look broken in the cerebellum of 50 % of ethanol except for the nucleus. There was no significant difference diameter of the nucleus. It happened in general because of the shrinkage effect of ethanol. However, the authors recommend using 50 % of ethanol for routine staining.


La fijación es uno de los procesos en la preparación de muestras para histología y patología. El material más común para la fijación es la formalina tamponada. Sin embargo, el daño a las células que se mantienen en formalina durante mucho tiempo, hace necesario buscar otros materiales de fijación. Además, el paraformaldehido también es perjudicial para el cuerpo humano y el medio ambiente natural. El etanol es uno de los materiales de fijación alternativos que se ha utilizado durante muchos años, con diversos objetivos, tanto en la tinción de rutina como en la inmunohistoquímica. Sin embargo no se ha confirmdo su efecto con microscopio electrónico. Los autores estudiaron el efecto del 50 % de etanol sobre la membrana celular, los orgánulos y el núcleo de las células de Purkinje observados en un microscopio óptico y un microscopio de transmisión electrónico (TEM). Luego se comparó con la formalina tamponada. En el microscopio óptico se observó que ambas fijaciones no tienen efectos diferentes a la morfología de la membrana celular, el citoplasma, el núcleo de las células de Purkinje y los neutrófilos. Suponemos que nuestra concentración de 50 % de etanol es casi la misma que BF 10 % en la capacidad de endurecer el tejido y la absorción de color según el estudio anterior. En TEM, la estructura de la membrana celular, los orgánulos y el citoplasma de la célula de Purkinje presentaban daño en el cerebelo con un 50 % de etanol, a excepción del núcleo. No hubo diferencia significativa en el diámetro del núcleo. En general lo anterior se debió al efecto de contracción del etanol. En conclusión los autores recomiendan usar 50% de etanol para la tinción de rutina.


Subject(s)
Animals , Male , Mice , Brain/drug effects , Brain/ultrastructure , Tissue Fixation/methods , Ethanol/pharmacology , Microscopy, Electron , Organelles/drug effects , Organelles/ultrastructure , Mice, Inbred BALB C
7.
Int. j. morphol ; 38(2): 461-471, abr. 2020. graf
Article in English | LILACS | ID: biblio-1056463

ABSTRACT

This experiment was designed to study the administration of normal doses of one of recent antimalarial drug and coadministration of vitamin E on the kidney tissue. A total twenty-four adult male albino rats were used and divided into four groups: the first one served as a control, the second received artemether orally for three days consecutively. The rats of the third and fourth groups received the same dose of artemether concomitantly with 50 and 100 mg/kg vitamin E orally daily for 2 weeks. After the last dose, the rats were sacrificed and the kidney tissues with blood samples obtained and processed for light, electron microscopic and biochemical analysis. Histologically, artemether treated kidneys showed atrophied glomeruli with widened urinary space and kidney tubules were degenerated with disturbed contour and some vacuoles inside it. Ultrastructurally, the glomeruli of this group showed hypertrophic endothelial cells, irregularity of its basement membrane, disrupted foot processes and filtration slits. The kidney tubule cells showed loss of basal infoldings, cytoplasmic vacuolation, polymorphic damaged swollen mitochondria a loss of its microvilli towards its capillary lumen. Artemether plus vitamin E of the rat kidney groups showed improvement of morphological changes compared to the changes seen in artemether alone. These data were confirmed by biochemical findings with marked improvement of blood urea and creatinine levels and increase of anti-oxidant enzyme activities of glutathione peroxidase and superoxide dismutase in the vitamin E treated groups. The results of this study revealed that vitamins E can improve the adverse changes of artemether of rat renal tissue.


Este proyecto fue diseñado para estudiar la administración de dosis normales de uno de los medicamentos antipalúdicos y de la administración de vitamina E en el tejido renal. Se utilizaron 24 ratas albinas machos adultas divididas en cuatro grupos: el primero sirvió como control, el segundo recibió arteméter por vía oral durante tres días consecutivos. Las ratas del tercer y cuarto grupos recibieron la misma dosis de arteméter concomitantemente con 50 y 100 mg / kg de vitamina E por vía oral diariamente durante 2 semanas. Después de la última dosis, las ratas fueron sacrificadas y se obtuvo el tejido renal de cada muestra los cuales fueron procesados para análisis con microscopías de luz y electrónica, además de exámenes bioquímicos. Histológicamente, los riñones tratados con arteméter mostraron atrofia glomerular con espacio urinario ensanchado y túbulos renales degenerados con contorno alterado y algunas vacuolas en su interior. Ultraestructuralmente, los glomérulos de este grupo mostraron células endoteliales hipertróficas, irregularidad de su membrana basal, procesos alterados del pie y hendiduras de filtración. Las células del túbulo renal mostraron pérdida de inflexiones basales, vacuolación citoplasmática, mitocondrias dañadas y pérdida de sus microvellosidades hacia la luz capilar. Arteméter más vitamina E en los grupos de riñón de rata mostraron una mejora de los cambios morfológicos, en comparación con los cambios observados en arteméter solamente. Estos datos fueron confirmados por hallazgos bioquímicos con una marcada mejoría de los niveles de urea y creatinina en sangre y un aumento de las actividades enzimáticas antioxidantes de la glutatión peroxidasa y la superóxido dismutasa en los grupos tratados con vitamina E. Los resultados de este estudio revelaron que la vitamina E puede mejorar los cambios adversos del arteméter del tejido renal de la rata.


Subject(s)
Animals , Male , Rats , Vitamin E/pharmacology , Acute Kidney Injury/chemically induced , Artemether/toxicity , Vitamin E/administration & dosage , Microscopy, Electron , Biomarkers/analysis , Rats, Wistar , Kidney/drug effects , Kidney/pathology , Kidney/ultrastructure , Antimalarials/toxicity
8.
Int. j. morphol ; 38(2): 505-512, abr. 2020. graf
Article in English | LILACS | ID: biblio-1056469

ABSTRACT

Sexual dimorphism exists at all levels of the nervous system. These sex differences could underlie genderrelated differences in behavior and neuropsychological function, as well as the gender differences in the prevalence of various mental disorders such as autism, attention deficit disorders, and schizophrenia. Myelination, on the other hand, is a unique cellular process that can have a dramatic impact on the structure and physiology of an axon and its surrounding tissue. The corpus callosum (CC) is the largest of the brain commissures, which connects the cerebral cortices of the two hemispheres, and provides interhemispheric connectivity for information transfer and processing between cortical regions. Variation in the axonal properties of CC will alter the interhemispheric connectivity. The CC consists of myelinated and unmyelinated axons, glial cells and blood vessels. Several functional studies have reported that the function of CC is associated with its axons density and myelination properties. The sexual dimorphism in the axonal content of the CC has always been controversial; hence, the aim of this study was to analyze the differences in axons' diameter and myelin sheath thickness of the CC between male and female rats. For this purpose, five pairs of adult male and female rats were perfused and the CC were removed and sectioned. Four sections from different subregions of the corpus callosum that represent the genu, anterior body, posterior body, and splenium of the CC were stained and electron microscopic images were captured using stereological guidelines. Later, the axons diameter and myelin sheath thickness for each subregion were calculated and compared between males and females. Our preliminary findings of the present study indicated region specific differences in the myelinated axon thickness and diameter in the CC between male and female rats.


El dimorfismo sexual existe en todos los niveles del sistema nervioso. Estas diferencias de sexo podrían ser la base de las diferencias de comportamiento y función neuropsicológica relacionadas con el sexo, así como las diferencias en la prevalencia de diversos trastornos mentales, como el autismo, los trastornos por déficit de atención y la esquizofrenia. La mielinización, por otro lado, es un proceso celular único que puede tener un impacto dramático en la estructura y fisiología de un axón y su tejido circundante. El cuerpo calloso (CC) es la mayor comisura cerebral, que conecta las cortezas cerebrales de ambos hemisferios, y proporciona la conectividad interhemisférica para la transferencia y el procesamiento de información entre regiones corticales. La variación en las propiedades axonales de CC alterará la conectividad interhemisférica. El CC consiste en axones mielinizados y no mielinizados, células gliales y vasos sanguíneos. Varios estudios funcionales han informado que la función de CC está asociada con la densidad de axones y las propiedades de mielinización. El dimorfismo sexual en el contenido axonal del CC siempre ha sido controvertido; por lo tanto, el objetivo de este estudio fue analizar las diferencias en el diámetro de los axones y el grosor de la vaina de mielina del CC entre ratas macho y hembra. Para este propósito, se perfundieron cinco pares de ratas macho y hembra adultas y se extrajeron y seccionaron las CC. Se tiñeron cuatro secciones de diferentes subregiones del cuerpo calloso que representan el genu, el cuerpo anterior, el cuerpo posterior y el esplenio y se capturaron imágenes de microscopía electrónicas utilizando referencias estereológicas. Posteriormente se calculó el diámetro de los axones y el grosor de la vaina de mielina para cada subregión y se compararon entre machos y hembras. Nuestros hallazgos preliminares del presente estudio indicaron diferencias específicas en el grosor y diámetro del axón mielinizado en el CC entre ratas macho y hembra.


Subject(s)
Animals , Male , Female , Rats , Axons/ultrastructure , Sex Characteristics , Corpus Callosum/ultrastructure , Myelin Sheath/ultrastructure , Microscopy, Electron , Corpus Callosum/cytology
9.
Article in English | WPRIM | ID: wpr-810955

ABSTRACT

Novel coronavirus (SARS-CoV-2) is found to cause a large outbreak started from Wuhan since December 2019 in China and SARS-CoV-2 infections have been reported with epidemiological linkage to China in 25 countries until now. We isolated SARS-CoV-2 from the oropharyngeal sample obtained from the patient with the first laboratory-confirmed SARS-CoV-2 infection in Korea. Cytopathic effects of SARS-CoV-2 in the Vero cell cultures were confluent 3 days after the first blind passage of the sample. Coronavirus was confirmed with spherical particle having a fringe reminiscent of crown on transmission electron microscopy. Phylogenetic analyses of whole genome sequences showed that it clustered with other SARS-CoV-2 reported from Wuhan.


Subject(s)
China , Coronavirus , Crowns , Genome , Humans , Korea , Microscopy, Electron , Microscopy, Electron, Transmission , Phylogeny , Vero Cells
10.
J. venom. anim. toxins incl. trop. dis ; 26: e20200023, 2020. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1135136

ABSTRACT

Endemic systemic mycoses remain a health challenge, since these opportunistic diseases are increasingly infecting immunosuppressed patients. The simultaneous use of antifungal compounds and other drugs to treat infectious or non-infectious diseases has led to several interactions and undesirable effects. Thus, new antifungal compounds should be investigated. The present study aimed to evaluate the activity of liriodenine extracted from Annona macroprophyllata on agents of systemic mycoses, with emphasis on the genus Paracoccidioides. Methods: The minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were determined by the microdilution method. The cellular alterations caused by liriodenine on a standard P. brasiliensis (Pb18) strain were evaluated by transmission and scanning electron microscopy. Results: Liriodenine was effective only in 3 of the 8 strains of the genus Paracoccidioides and in the Histoplasma capsulatum strain, in a very low concentration (MIC of 1.95 µg.mL-1); on yeasts of Candida spp. (MIC of 125 to 250 µg.mL-1), including C. krusei (250 µg.mL-1), which has intrinsic resistance to fluconazole; and in Cryptococcus neoformans and Cryptococcus gattii (MIC of 62.5 µg.mL-1). However, liriodenine was not effective against Aspergillus fumigatus at the studied concentrations. Liriodenine exhibited fungicidal activity against all standard strains and clinical isolates that showed to be susceptible by in vitro tests. Electron microscopy revealed cytoplasmic alterations and damage to the cell wall of P. brasiliensis (Pb18). Conclusion: Our results indicate that liriodenine is a promising fungicidal compound that should undergo further investigation with some chemical modifications.(AU)


Subject(s)
Paracoccidioides , Microscopy, Electron , Microbial Sensitivity Tests , Cryptococcus neoformans , Cryptococcus gattii , Mycoses , Antifungal Agents/isolation & purification
11.
Int. j. morphol ; 37(2): 694-700, June 2019. graf
Article in Spanish | LILACS | ID: biblio-1002279

ABSTRACT

Spondylus limbatus es una especie bajo protección especial en México, de la que existe poca información biológica y nada sobre estudios histológicos o de ultraestructura del ovario. El objetivo de esta investigación fue caracterizar la morfología ultraestructural de los gametos femeninos maduros y en degeneración. La gónada femenina de S. limbatus en estado de madurez presentó ovocitos postvitelogénicos de 60-70 µm de diámetro, que presentan el aspecto característico de células metabólicamente activas y altamente sintetizadoras. La membrana citoplasmática posee especializaciones destinadas a aumentar la superficie de absorción de la célula, las microvellosidades; el citoplasma presenta numerosos sistemas membranosos relacionados con la síntesis de material de reserva y secreción; y el patrón de organización nuclear altamente lobulado, y por consiguiente con una gran superficie que asegura el intercambio núcleo-citoplasma, se incorpora de forma estructural al proceso de vitelogénesis. Finalmente, se describen los cambios ultraestructurales resultantes de la lisis de los ovocitos: colapso de las membranas nuclear y citoplásmica, y presencia de células hemocíticas macrófagas.


Spondylus limbatus is a species under special protection in Mexico, of which there is little or no information in the literature of biological, histological or ultrastructural studies of the ovary. The objective of this research was to characterize the ultrastructural morphology of mature and degenerating female gametes. The female gonad of S. limbatus in mature state presented post-vitellogenic oocytes 60-70 µm in diameter, which have characteristics of metabolically active and highly synthesizing cells. The cytoplasmic membrane has specializations designed to increase the absorption surface of the cell, the microvilli; the cytoplasm presents numerous membranous systems related to synthesis of reserve and secretion material as well as the highly lobed nuclear organization pattern; a large surface that ensures core-cytoplasm exchange, is structurally incorporated into the vitellogenesis process. Finally, ultrastructural changes resulting from the lysis of the oocytes are described: collapse of nuclear and cytoplasmic membranes, and the presence of macrophage hemocytic cells.


Subject(s)
Animals , Female , Oocytes/ultrastructure , Bivalvia , Gonads/ultrastructure , Reproduction , Microscopy, Electron
12.
Rev. colomb. reumatol ; 26(2): 118-128, ene.-jun. 2019. graf
Article in Spanish | LILACS | ID: biblio-1115669

ABSTRACT

RESUMEN La proliferación del tejido sinovial, que es llamada pannus, se ha considerado como una manifestación tardía, inactiva e irreversible de la artritis reumatoide (AR), contrario a lo que históricamente se ha estudiado. Se realizó una búsqueda de la literatura para realizar una revisión narrativa e histórica respecto al surgimiento del término pannus y su papel en la artritis reumatoide. Estudios de microscopia de luz han mostrado el carácter destructivo de este tejido con hallazgos característicos de la AR, corroborados con microscopia electrónica arios más tarde. Estos hallazgos llevaron a caracterizar el componente celular del pannus con gran número de células inmunológicas y de líneas celulares específicas con propiedades especiales como los sinoviocitos similares a fibroblastos. Este componente celular es el origen de una gran cantidad de citoquinas y proteinasas que perpetúan y causan el daño óseo y del cartílago. Este componente inflamatorio ha sido evidente también con el desarrollo de técnicas de imágenes, como la resonancia magnética y la ultrasonografía, que muestran un papel activo del tejido sinovial engrosado, junto a la hipervascularización en el daño articular y la reversibilidad de estos cambios tras el tratamiento. Las evidencias contempladas permiten concluir que el pannus como evidencia histológica (más que clínica) se refiere a la proliferación del tejido sinovial e incluye un gran componente celular activo que genera y perpetúa la inflamación y, por tanto, la enfermedad.


ABSTRACT Pannus refers to synovial tissue proliferation, and has been considered a late, inactive and irreversible manifestation of rheumatoid arthritis (RA), contrary to historical findings. A literature search was performed on terminology about pannus and its historical role in the pathophysiology of RA. Light microscopy studies have shown the destructive impact of pannus tissue with very specific abnormalities, corroborated a year later with electronic microscopy. Some of these findings are the isolation of the immunological cells inside the tissue, especially one cell line with particular capacities, called synoviocytes similar to fibroblasts. This cellular component is the source a large quantity of cytokines and proteinases that perpetuate and cause bone and cartilage damage. Inflammation has been seen in many image techniques, such as magnetic resonance and ultrasound. These show the role of tissue widening and hyper-vascularization in tissue damage, and some reversibility after treatment of RA. With the evidence presented it is possible to conclude that pannus refers to a histological (more than clinical) term for synovial hypertrophy, and includes a large component of cell activity that generates and perpetuates inflammation and thus the disease.


Subject(s)
Humans , Arthritis, Rheumatoid , Synovitis , Microscopy, Electron , Magnetic Resonance Spectroscopy , Ultrasonography
13.
Rev. biol. trop ; 67(1): 83-93, Jan.-Mar. 2019. tab, graf
Article in English | LILACS | ID: biblio-1041896

ABSTRACT

Abstract The solubility equilibrium of calcite is influenced by physicochemical, climatic and biological factors. Annual cycles of exceptionally prolonged drought, in conjunction with naturally occurring diffuse organic pollution, generate the unique conditions for the precipitation of lithified carbonate structures (microbialites). The aim of this article is to analyze the possible implications of calcite precipitation produced in mats of Cladophora sp. in an Andean subtropical basin, considering it is the first time this phenomenon is described for the region. We collected samples from selected sites at the Lules River Basin, in four sampling dates between the years 2003 and 2004, within a monitoring work of 15 years. Samples were analyzed using an electron microscope and X-ray diffraction analysis. We found that Gomphonema sp. attached to Cladophora sp. contributes to precipitation of calcite and formation of microbialite like structures, in the studied area. This work presents an initial discussion of the discovery of microbialites-like structures attached to Cladophora sp. mats in a subtropical Andean stream and the environmental conditions that lead to their production, as well as the possible ecological implications of these microbialites.(AU)


Resumen La fase sólida de las sales de los cuerpos de agua juega un papel importante en la concentración de los elementos mayoritarios. El equilibrio de solubilidad de la calcita está influenciado por factores fisicoquímicos, climáticos y biológicos. Los ciclos anuales de sequía excepcionalmente prolongada, junto con la contaminación orgánica difusa de origen natural, generan condiciones únicas para la precipitación de estructuras de carbonato litificado (microbialitos). El objetivo de este artículo es analizar las posibles implicaciones de la precipitación de calcita producida en Cladophora sp. en una cuenca subtropical andina, considerando que es la primera vez que se describe este fenómeno para la región. Recolectamos muestras en sitios seleccionados en la Cuenca del Río Lules, en cuatro fechas de muestreo entre 2003 y 2004, en el marco de un trabajo de monitoreo de quince años. Usamos red Surber para realizar los muestreos. Las muestras de algas, una vez libres de macroinvertebrados, se secaron y pesaron. Analizamos utilizando microscopía electrónica y difracción de rayos X. Encontramos que Gomphonema sp. unido a Cladophora contribuye a la precipitación de calcita y la formación de estructuras similares a microbialitos, en el área estudiada. Este trabajo presenta una discusión inicial sobre el descubrimiento de estructuras similares a microbialitos unidas a filamentos de Cladophora sp. en una cuenca andina subtropical y las condiciones ambientales que conducen a su producción, así como las posibles implicaciones ecológicas de lo mencionado anteriormente.(AU)


Subject(s)
Lithium Carbonate/analysis , Diatoms/chemistry , Environmental Pollution , Droughts , Argentina , X-Ray Diffraction/instrumentation , Microscopy, Electron/instrumentation , Sampling Studies
14.
Rev. odontol. Univ. Cid. São Paulo (Online) ; 31(2): 116-124, abr/jun 2019. il.
Article in Portuguese | LILACS, BBO | ID: biblio-1021582

ABSTRACT

Atualmente o uso de instrumentos rotatórios é uma realidade, porém, estes apresentam restos de resíduos na superfície de corte. Sendo assim, o objetivo deste trabalho foi avaliar por meio de microscopia eletrônica de varredura (MEV), a presença de resíduos na superfície de corte de 20 instrumentos rotatórios de NiTi sem uso. Foram divididos em quatro grupos, a saber: Grupo A - TwistedFile® (n=5), Grupo B - BioRaCe® (n=6), Grupo C - Mtwo® (n=4) e GrupoD - EndoWave® (n=5). As pontas dos instrumentos foram microfotografadas com aumento de 190X a partir do diâmetro inicial para verificar a presença de resíduos. Em seguida, os instrumentos passaram por um rigoroso processo de limpeza e novamente microfotografados com o mesmo padrão de aumento, observando-se a ponta do instrumento e a 5mm da ponta do instrumento. Os dados obtidos foram tabulados e submetidos à análise percentual e estatística valendo-se do teste Exato de Fisher e nível de significância de 5%. No que se refere à sujidade ocorreram diferenças estatisticamente significantes entre as limas Mtwo® com os outros instrumentos (p<0,05). Concluiu-se que todos os instrumentos estavam sujos, exceto a marca Mtwo® e que após os procedimentos de limpeza a superfície de corte estava isenta de resíduos.


Currently the use of rotary instruments is a reality, however, they have leftover residue on the cut surface. Thus, the aim of this study was to evaluate by means of scanning electron microscopy (SEM), the presence of residues on the surface of cut 20 NiTi rotary instruments unused. Were divided into four groups as follows: Group A - TwistedFile® (n = 5) Group B - BioRaCe® (n = 6) Group C - Mtwo® (n = 4) Group D - EndoWave® (n = 5). The tip of the instruments was photomicrographed with 190X at magnification from the initial diameter for the presence of residues. Then, instruments passed through a rigorous cleaning and again photomicrographed with the same magnification observing the tip of the instrument and 5mm from the tip of the instrument. Data were tabulated and analyzed statistically percentage and taking advantage of the Fisher exact test and a significance level of 5%. With regard to dirt statistically significant differences between the files Mtwo® with other instruments (p <0.05). It was concluded that all instruments were dirty except Mtwo® brand and after cleaning procedures the cut surface was free of residues.


Subject(s)
Titanium , Microscopy, Electron , Dental Instruments , Nickel
15.
Experimental Neurobiology ; : 279-288, 2019.
Article in English | WPRIM | ID: wpr-739538

ABSTRACT

Charcot-Marie Tooth disease type 1A (CMT1A), the major type of CMT, is caused by duplication of peripheral myelin protein 22 (PMP22) gene whose overexpression causes structural and functional abnormalities in myelination. We investigated whether miRNA-mediated regulation of PMP22 expression could reduce the expression level of PMP22, thereby alleviating the demyelinating neuropathic phenotype of CMT1A. We found that several miRNAs were down-regulated in C22 mouse, a CMT1A mouse model. Among them, miR-381 could target 3′ untranslated region (3′UTR) of PMP22 in vitro based on Western botting and quantitative Real Time-PCR (qRT-PCR) results. In vivo efficacy of miR-381 was assessed by administration of LV-miR-381, an miR-381 expressing lentiviral vector, into the sciatic nerve of C22 mice by a single injection at postnatal day 6 (p6). Administration of LV-miR-381 reduced expression level of PMP22 along with elevated level of miR-381 in the sciatic nerve. Rotarod performance analysis revealed that locomotor coordination of LV-miR-381 administered C22 mice was significantly enhanced from 8 weeks post administration. Electrophysiologically, increased motor nerve conduction velocity was observed in treated mice. Histologically, toluidine blue staining and electron microscopy revealed that structural abnormalities of myelination were improved in sciatic nerves of LV-miR-381 treated mice. Therefore, delivery of miR-381 ameliorated the phenotype of peripheral neuropathy in CMT1A mouse model by down-regulating PMP22 expression. These data suggest that miRNA can be used as a potent therapeutic strategy to control diseases with copy number variations such as CMT1A.


Subject(s)
Animals , Demyelinating Diseases , In Vitro Techniques , Mice , MicroRNAs , Microscopy, Electron , Myelin Sheath , Neural Conduction , Peripheral Nervous System Diseases , Phenotype , Sciatic Nerve , Tolonium Chloride , Tooth Diseases , Untranslated Regions
16.
Article in English | WPRIM | ID: wpr-763268

ABSTRACT

Nephrotic syndrome (NS) is a common chronic glomerular disease in children characterized by significant proteinuria with resulting hypoalbuminemia, edema, and hyperlipidemia. Renal biopsy findings of diffuse foot processes effacement on electron microscopy and minimal change disease, focal segmental glomerulosclerosis (FSGS), or diffuse mesangial proliferation on light microscopy. It has been speculated that circulating permeability factors would be implicated in the pathogenesis of NS because they have been reportedly detected in the sera of patients and in experimental models of induced proteinuria. Moreover, a substantial portion of the patients with primary FSGS recurrence shortly after transplantation. This report reviews the current knowledge regarding the role of circulating permeability factors in the pathogenesis of proteinuria in NS and suggests future targeted therapeutic approaches for NS.


Subject(s)
Biopsy , Child , Edema , Foot , Glomerulosclerosis, Focal Segmental , Humans , Hyperlipidemias , Hypoalbuminemia , Microscopy , Microscopy, Electron , Models, Theoretical , Nephrosis, Lipoid , Nephrotic Syndrome , Permeability , Proteinuria , Recurrence
17.
Arq. Inst. Biol ; 86: e0232019, 2019. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1024605

ABSTRACT

Rust, caused by the biotrophic fungus Olivea neotectonae, stands out as an important disease in teak plantations in Brazil. Considering the current importance of this rust and the need to obtain additional basic information about its causal agent to better disease management, the present study aimed to analyze the morphology of O. neotectonae using light microscopy and demonstrate the infection process in teak leaves using scanning electron microscopy techniques (SEM). The morphological characteristics observed using light microscopy were similar to those described in the literature for this species. SEM revealed that the infection structures of the pathogen penetrated the teak leaf through the stomata complex. This study provides the first microscopic evidence of the infection process of Olivea neotectonae in leaves of teak plants.(AU)


A ferrugem, causada pelo fungo biotrófico Olivea neotectonae, destaca-se como uma doença importante nas plantações de teca no Brasil. Considerando a importância atual dessa ferrugem e a necessidade de obter informações básicas adicionais sobre seu agente causal para melhor manejo da doença, o presente estudo teve como objetivo analisar a morfologia da O. neotectonae utilizando microscopia de luz e demonstrar o processo de infecção em folhas de teca por meio de técnicas de microscopia eletrônica de varredura (MEV). As características morfológicas observadas em microscopia de luz foram semelhantes às descritas na literatura para essa espécie. A MEV revelou que as estruturas de infecção do patógeno penetraram na folha de teca através do complexo estomático. Este estudo fornece a primeira evidência microscópica do processo de infecção de Olivea neotectonae em folhas de plantas de teca.(AU)


Subject(s)
Pest Control , Rainforest , Fungi , Plant Diseases , Microscopy, Electron/methods
18.
Article in English | WPRIM | ID: wpr-764239

ABSTRACT

Canine adenovirus type 1 (CAV-1) infection results in hepatitis in dogs. In this study, we investigated the biologic and genetic characteristics of the CAV-1 vaccine strain (CAV1V) to improve quality control about CAV vaccine. The identity of CAV1V as CAV-1 was confirmed based on its cytopathic effects and the results of hemagglutination (HA) and immunofluorescence assays, and electron microscopy. The CAV1V strain reached 10(7.5) TCID(50)/mL in MDCK cells at 4 days post-inoculation and exhibited hemmagglutination activity of 256 U using guinea pig erythrocytes. Intranuclear fluorescence in the infected cells was observed and typical adenoviruses were observed in electon microscope. CAV1V strain was identified as a CAV-1 strain by nucleotide sequence analysis. In a comparison of the nucleotide sequences of the fiber genes of several CAV strains, CAV1V showed the highest similarity (99.8%) with the GLAXO strain, which was isolated in Canada. Our biological characterization of CAV1V will facilitate quality control of the canine hepatitis vaccine.


Subject(s)
Adenoviridae , Adenoviruses, Canine , Animals , Base Sequence , Canada , Dogs , Erythrocytes , Fluorescence , Fluorescent Antibody Technique , Guinea Pigs , Hemagglutination , Hepatitis , Madin Darby Canine Kidney Cells , Microscopy, Electron , Quality Control
19.
Experimental Neurobiology ; : 451-457, 2019.
Article in English | WPRIM | ID: wpr-763782

ABSTRACT

Currently, compared to jaw-closing (JC) α-motoneurons, the information on the distribution and morphology of glutamatergic synapses on the jaw-closing (JC) γ-motoneurons, which may help elucidate the mechanism of isometric contraction of the JC muscle, is very limited. This study investigated the distribution and ultrastructural features of vesicular glutamate transporter 1 (VGLUT1)- and VGLUT2-immunopositive (+) axon terminals (boutons) on JC γ-motoneurons by retrograde tracing with horseradish peroxidase, electron microscopic immunocytochemistry, and quantitative analysis. About 35% of the boutons on identified JC γ-motoneurons were VGLUT+, and of those, 99% were VGLUT2+. The fraction of VGLUT1+ boutons of all boutons and the percentage of membrane of JC γ-motoneurons covered by these boutons were significantly lower than those for the JC α-motoneurons, revealed in our previous work. The bouton volume, mitochondrial volume, and active zone area of the VGLUT2+ boutons on the JC γ-motoneurons were uniformly small. These findings suggest that the JC γ-motoneurons, in contrast to the JC α-motoneurons, receive generally weak glutamatergic synaptic input almost exclusively from VGLUT2+ premotoneurons that form direct synapse with motoneurons.


Subject(s)
Animals , Horseradish Peroxidase , Immunohistochemistry , Isometric Contraction , Membranes , Microscopy, Electron , Mitochondrial Size , Motor Neurons , Presynaptic Terminals , Rats , Synapses , Vesicular Glutamate Transport Protein 1
20.
Article in Chinese | WPRIM | ID: wpr-773491

ABSTRACT

OBJECTIVE@#To investigate the relationship between necroptosis and apoptosis in MCET3-E1 cell death induced by glucocorticoids.@*METHODS@#MC3T3-E1 cells were incubated with 10-6 mol/L dexamethasone followed by treatment with the apoptosis inhibitor z-VAD-fmk (40 μmol/L) or the necroptosis inhibitor necrostatin-1 (40 μmol/L) for 2 h. At 72 h after incubation with dexamethasone, the cells were harvested to determine the cell viability using WST-1 assay and the rate of necrotic cells using annexin V/PI double staining; the percentage of apoptotic cells was determined using Hoechst staining. The mitochondrial membrane potential and the level of ATP in the cells were also evaluated. Transmission electron microscopy was used to observe the microstructural changes of the cells. The expressions of RIP-1 and RIP-3 in the cells were detected by Western blotting.@*RESULTS@#At a concentration of 10-6 mol/L, dexamethasone induced both apoptosis and necroptosis in MC3T3- E1 cells. Annexin V/PI double staining showed that inhibition of cell apoptosis caused an increase in cell necrosis manifested by such changes as mitochondrial swelling and plasma membrane disruption, as shown by electron microscopy; Hoechst staining showed that the percentage of apoptotic cells was significantly reduced. When necroptosis was inhibited by necrostatin-1, MC3T3-E1 cells showed significantly increased apoptosis as shown by both AV/PI and Hoechst staining, and such changes were accompanied by changes in mitochondrial membrane potential and ATP level in the cells.@*CONCLUSIONS@#In the process of dexamethasone-induced cell death, necroptosis and apoptosis can transform reciprocally accompanied by functional changes of the mitochondria.


Subject(s)
3T3 Cells , Adenosine Triphosphate , Animals , Apoptosis , Cell Death , Dexamethasone , Membrane Potential, Mitochondrial , Mice , Microscopy, Electron , Mitochondria , Necrosis
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