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1.
Rev. biol. trop ; 69(supl. 1)mar. 2021.
Article in English | LILACS, SaludCR | ID: biblio-1507768

ABSTRACT

Introduction: Echinoderm coelomocytes have traditionally been investigated through a morphological approach using light microscopy, which relies on the idea of constant cell shape as a stable character. However, this can be affected by biotic or abiotic conditions. Objective: To analyze if the consistency in cell morphology offered by the cytocentrifugation method, might be used as a convenient tool to study echinoderm coelomocytes. Methods: Cells of Echinaster (Othilia) brasiliensis (Asteroidea), Holothuria (Holothuria) tubulosa (Holothuroidea), Eucidaris tribuloides, Arbacia lixula, Lytechinus variegatus, and Echinometra lucunter (Echinoidea) were spread on microscope slides by cytocentrifugation, stained, and analyzed through light microscopy. Additionally, fluorescence microscopy, scanning electron microscopy, and energy-dispersive x-ray spectroscopy were applied to cytospin preparations, to complement the analysis of granular and colorless spherulocytes of Eucidaris tribuloides. Results: Altogether, 11 cell types, including phagocytes, spherulocytes, vibratile cells, and progenitor cells were identified in the samples analyzed. The granular spherulocyte, a newly-described cell type, was observed in all Echinoidea and was very similar to the acidophilic spherulocytes of Holothuria (Holothuria) tubulosa. Conclusions: Cytocentrifugation proved to be versatile, either as the main method of investigation in stained preparations, or as a framework on which other procedures may be performed. Its ability to maintain a constant morphology allowed accurate correspondence between live and fixed/stained cells, differentiation among similar spherulocytes as well as comparisons between similar cells of Holothuroidea and Echinoidea.


Introducción: Los celomocitos de equinodermos se han investigado tradicionalmente a través de un enfoque morfológico utilizando microscopía óptica, que se basa en la idea de la forma celular constante como un carácter estable. Sin embargo, esto puede verse afectado por condiciones bióticas o abióticas. Objetivo: Analizar si la consistencia en la morfología celular que ofrece el método de citocentrifugación podría utilizarse como una herramienta conveniente para estudiar los celomocitos de equinodermos. Métodos: Células de Echinaster (Othilia) brasiliensis (Asteroidea), Holothuria (Holothuria) tubulosa (Holothuroidea), Eucidaris tribuloides, Arbacia lixula, Lytechinus variegatus y Echinometra lucunter (Echinoidea) se esparcieron en portaobjetos de microscopio por citocentrifugación, se tiñeron y analizaron mediante microscopía óptica. Adicionalmente, se aplicó microscopía de fluorescencia, microscopía electrónica de barrido y espectroscopía de rayos X con dispersión de energía a las preparaciones de citoespina, para complementar el análisis de los esferulocitos granulares e incoloros de Eucidaris tribuloides. Resultados: En total, se identificaron en las muestras analizadas 11 tipos de células, incluidos fagocitos, esferulocitos, células vibrátiles y células progenitoras. El esferulocito granular, un tipo de célula recién descrito, se observó en todos los Echinoidea y fue muy similar a los esferulocitos acidófilos de Holothuria (Holothuria) tubulosa. Conclusiones: La citocentrifugación demostró ser un método bastante versátil, ya sea como el método principal de investigación en preparaciones teñidas o como un marco en el que se pueden realizar otros procedimientos. Su capacidad para mantener una morfología constante permitió una correspondencia precisa entre las células vivas y las células fijas/teñidas, la diferenciación entre esferulocitos similares, así como comparaciones entre células similares de Holothuroidea y Echinoidea.


Subject(s)
Animals , Spectrometry, X-Ray Emission/methods , Echinodermata/microbiology , Centrifugation/instrumentation , Cell Nucleus Shape
2.
Arq. neuropsiquiatr ; 74(10): 816-822, Oct. 2016. tab, graf
Article in English | LILACS | ID: lil-796832

ABSTRACT

ABSTRACT Objective To define how to best handle cerebrospinal fluid (CSF) specimens to obtain the highest positivity rate for the diagnosis of malignancy, comparing two different methods of cell concentration, sedimentation and cytocentrifugation. Methods A retrospective analysis of 411 CSF reports. Results This is a descriptive comparative study. The positive identification of malignant CSF cells was higher using the centrifuge than that using the Suta chamber (27.8% vs. 19.0%, respectively; p = 0.038). Centrifuge positively identified higher numbers of malignant cells in samples with a normal concentration of white blood cells (WBCs) (< 5 cells/mm3) and with more than 200 cells/mm3, although this was not statistically significant. There was no lymphocyte loss using either method. Conclusions Cytocentrifugation positively identified a greater number of malignant cells in the CSF than cytosedimentation with the Suta chamber. However, there was no difference between the methods when the WBC counts were within the normal range.


RESUMO Objetivo Definir qual a melhor forma de concentrar amostras de LCR para obter maior porcentagem de positividade para o diagnóstico de infiltração neoplásica. comparando dois métodos diferentes de concentração de células, sedimentação e citocentrifugação. Métodos Análise retrospectiva de 411 laudos de LCR. Resultados Estudo comparativo descritivo. A identificação de células neoplásicas no LCR foi mais elevada quando usada a citocentrífuga do que a câmara de Suta (28% vs 19,0%, respectivamente; p = 0,038). Centrifugação identificou maior número de células neoplásicas em amostras com concentração de células < 5 células/mm3 e superior a 200 células/mm3, embora não significativo. Não houve perda de linfócitos usando qualquer um dos métodos. Conclusões A citocentrifugação identificou um número maior de células malignas no LCR do que a sedimentação com a câmara de Suta. No entanto, não houve diferença entre os métodos quando as contagens de leucócitos estavam dentro do intervalo normal.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Young Adult , Centrifugation/instrumentation , Centrifugation/methods , Central Nervous System Neoplasms/cerebrospinal fluid , Reference Standards , Reference Values , Specimen Handling/instrumentation , Specimen Handling/methods , Time Factors , Leukemia/cerebrospinal fluid , Cerebrospinal Fluid/cytology , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , Leukocyte Count
3.
Rev. argent. microbiol ; 41(3): 163-167, jul.-sep. 2009. mapas, tab
Article in Spanish | LILACS | ID: lil-634631

ABSTRACT

La miel es un producto natural que presenta una carga microbiana muy baja. No obstante, durante el procesamiento empleado para transformarla en un producto comercial, que incluye una etapa de extracción, puede contaminarse. El objetivo de este trabajo fue evaluar la contaminación microbiológica en diferentes puntos del circuito dentro de las plantas de extracción de miel. En 50 muestras se cuantificó el número de hongos filamentosos y levaduras, así como el de coliformes totales, y se determinó la presencia de Salmonella spp. Todas las muestras provenientes de los panales y de los extractores centrífugos presentaron un recuento de hongos filamentosos y levaduras ≤ 10 UFC/g de miel, y ausencia de coliformes. Sin embargo, se evidenciaron problemas de contaminación en la etapa de separación cera-miel de los opérculos, con indicios de que el sistema "en frío" implicaría mayores riesgos. De un total de 30 muestras procedentes de la bomba o de los tambores, 4 presentaron recuentos de hongos filamentosos y levaduras entre 10 y 50 UFC/g de miel. El presente trabajo muestra la importancia de prevenir contaminaciones provenientes de la separadora cera-miel y también la necesidad de realizar estudios microbiológicos en las plantas de extracción, ya que éstos podrían contribuir a determinar los puntos críticos en los sistemas de control de calidad.


One stage of honey production is extraction. Honey is a product with minimal types and levels of microorganisms; however it could be contaminated during its manipulation. The aim of this work was to evaluate the microbiological contamination of honey at different processing points. Mould and yeast, total coliform number as well as the presence of Salmonella spp. were determined in 50 samples. All comb and centrifugal honey-extractor samples showed low levels of mould and yeast (≤10 CFU/g of honey) and an absence of total coliforms. Contamination problems were observed at the uncapping stage of beeswax-capped honey separation, showing that the "unheated" honey process would imply more risks. Ten to fifty CFU/g of honey of mould and yeast were observed in four out of 30 samples from the honey pump and drums. The present work shows the importance of preventing contamination at the beeswax-honey separation stage, and also highlights the need to perform microbiological studies in the honeyhouse, which would contribute to determine critical points in control quality systems.


Subject(s)
Enterobacteriaceae/isolation & purification , Food Handling , Food Microbiology , Fungi/isolation & purification , Honey/microbiology , Argentina , Bacteria/isolation & purification , Centrifugation/instrumentation , Equipment Contamination , Food Handling/instrumentation , Quality Control , Temperature
5.
Acta physiol. pharmacol. ther. latinoam ; 42(1): 9-12, ene.-mar. 1992. ilus
Article in English | LILACS | ID: lil-113487

ABSTRACT

Un nuevo modelo de centrífuga humana de la síntesis de prostaglandinas endógenas es presentado. Las diferentes aplicaciones terapéuticas de esta máquina fueron demostradas en linfedema, arteriopatías obstructivas periféricas, síndrome de distrofia simpática refleja, retinopatía diabética plana o background y enfermedad coronaria


Subject(s)
Humans , Centrifugation/instrumentation , Endothelium, Vascular/physiology , Epoprostenol/biosynthesis , Centrifugation/methods
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