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1.
Proc Natl Acad Sci U S A ; 119(14): e2122937119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344419

RESUMO

The bright-field (BF) optical microscope is a traditional bioimaging tool that has been recently tested for depth discrimination during evaluation of specimen morphology; however, existing approaches require dedicated instrumentation or extensive computer modeling. We report a direct method for three-dimensional (3D) imaging in BF microscopy, applicable to label-free samples, where we use Köhler illumination in the coherent regime and conventional digital image processing filters to achieve optical sectioning. By visualizing fungal, animal tissue, and plant samples and comparing with light-sheet fluorescence microscopy imaging, we demonstrate the accuracy and applicability of the method, showing how the standard microscope is an effective 3D imaging device.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Animais , Simulação por Computador , Técnicas Histológicas , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos
2.
Acta Sci. Biol. Sci. ; 43: e53097, 2021. graf, tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-764585

RESUMO

This study assessed and compared different methods for vegetative propagation of a miniature ornamental pineapple hybrid (ORN-MUT), seeking to determine the best method for production of plantlets, as well as for removal of the PMWaV viral complex from plants cultured in vitro, for production of healthy parent plants. Pineapple wilt is a disease that can cause large economic and is caused by a viral complex called Pineapple mealybug wilt-associated virus (PMWaV). For this, four propagation methods were evaluated (conventional, stem sectioning, micropropagation and etiolation of nodal segments). The time necessary for each method and the number of plants formed were assessed. Stem tips (0.5 mm) were cultured and indexed for three PMWaV types. Conventional propagation produced 17 plantlets per plant in 566 days, stem sectioning produced 2.3 plantlets per stem in 591 days, while the conventional micropropagation technique produced 1,284 plants after four subcultures in 778 days. Stems etiolated for 60 days showed peak production in the second subculture, with 1,224 plants. This method required 883 days to obtain plants with ideal size for transplantation to the field. In turn, stems etiolated for 120 days produced 935 plants at the end of four subcultures, with peak output in the third subculture, in which the plants could be cultivated in the field after 943 days. Conventional micropropagation and etiolation for 60 days were the best methods for production of plantlets of the ORN-MUT hybrid. The results of this work showed that the cultivation of shoot tips is an efficient strategy to remove the PMWaV complex and obtain healthy mother plants and can be a useful tool for other varieties of pineapple.(AU)


Assuntos
Ananas/crescimento & desenvolvimento , Ananas/virologia , Estiolamento
3.
Acta sci., Biol. sci ; Acta sci., Biol. sci;43: e53097, 2021. graf, tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460976

RESUMO

This study assessed and compared different methods for vegetative propagation of a miniature ornamental pineapple hybrid (ORN-MUT), seeking to determine the best method for production of plantlets, as well as for removal of the PMWaV viral complex from plants cultured in vitro, for production of healthy parent plants. Pineapple wilt is a disease that can cause large economic and is caused by a viral complex called Pineapple mealybug wilt-associated virus (PMWaV). For this, four propagation methods were evaluated (conventional, stem sectioning, micropropagation and etiolation of nodal segments). The time necessary for each method and the number of plants formed were assessed. Stem tips (0.5 mm) were cultured and indexed for three PMWaV types. Conventional propagation produced 17 plantlets per plant in 566 days, stem sectioning produced 2.3 plantlets per stem in 591 days, while the conventional micropropagation technique produced 1,284 plants after four subcultures in 778 days. Stems etiolated for 60 days showed peak production in the second subculture, with 1,224 plants. This method required 883 days to obtain plants with ideal size for transplantation to the field. In turn, stems etiolated for 120 days produced 935 plants at the end of four subcultures, with peak output in the third subculture, in which the plants could be cultivated in the field after 943 days. Conventional micropropagation and etiolation for 60 days were the best methods for production of plantlets of the ORN-MUT hybrid. The results of this work showed that the cultivation of shoot tips is an efficient strategy to remove the PMWaV complex and obtain healthy mother plants and can be a useful tool for other varieties of pineapple.


Assuntos
Ananas/crescimento & desenvolvimento , Ananas/virologia , Estiolamento
4.
Surg Neurol Int ; 11: 229, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874732

RESUMO

BACKGROUND: Surgery of thickened-fibrolipoma filum terminale (FT) is performed routinely and without conflict but is not a risk-free surgical procedure. Intraoperative neurophysiological monitoring with mapping techniques can help to certify the FT before sectioning. However, a tailored surgical approach to cauda equina and a low threshold of surrounding nerve roots can confuse the final surgical decision. The aim is to demonstrate the usefulness of this double methodology for FT certification. METHODS: A prospective study collected and reviewed retrospectively, from 2015 to 2018, 40 patients undergoing an FT surgery section were included in the study. After opening the dura mater and under the microscope, the cauda equina mapping is performed and the recording of muscles of the lower limbs and the external anal sphincter. In addition, a high-intensity stimulation of constant current of an isolated FT for a short period of time and in a dry surgical field, obtaining a bilateral-polyradicular-symmetrical response of cauda equina nerve roots. RESULTS: Traditional motor mapping identified FT in 65% (26/40) of patients. Although, 35% (14/40) of the patients still have low-intensity stimuli response (<1 mA) of a muscle, especially anal sphincter. When this happens, the optimization of the dissection around FT is performed. After that, 25% (10/40) of the patients still having a muscle response in spite of seem isolated FT. Increasing the stimulation intensity up to 20 mA evoked a cauda equina response in all cases. No postoperative neurological impairment was observed in this series. CONCLUSION: This proposed methodology accurately confirms the FT so that it can be safely found and cut. The Double Neurophysiological Certification improves the gap of the traditional mapping techniques of cauda equina and can be used in a variety of more complex surgeries in this area.

5.
Neurol Sci ; 41(2): 249-256, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31598783

RESUMO

PURPOSE: Symptomatic Chiari type I malformation (CM) is treated with posterior fossa decompression with/ without duroplasty. Few authors suggested cerebellar tonsil caudal migration due to a supposed "caudal traction" of cranial nerve structures in a so-called occult tethered cord syndrome. For these authors, filum terminale (FT) sectioning may improve CM symptoms. The objective of this review is to evaluate the effect of FT sectioning on the treatment of CM. METHODS: Using the PRISMA guidelines for systematic reviews, we reviewed studies to evaluate patient's outcomes with CM who underwent FT sectioning. The MINORS instrument was used for methodological quality assessment. The included studies' levels of evidence (LOE) were classified according to the Oxford Centre of Evidence-Based Medicine. RESULTS: Two studies from the same group of authors were included. We cannot assure if the cited cases in the first study were also included in their latter published study. The described results suggest that outcomes were not collected in a standardized fashion. Outcomes are described vaguely as a percentage of improvement. Case series samples were small and included not only patients with CM but also patients with scoliosis and syringomyelia. The MINORS score reported that both studies had low methodological quality. Both included studies were classified as level 4 of evidence. CONCLUSION: There is no scientific support for filum terminale sectioning in patients with CM without evidence of tethered cord. This procedure may be considered experimental and should be validated in a strict criterion of inclusion clinical trial comparing outcomes in posterior fossa decompression.


Assuntos
Malformação de Arnold-Chiari/cirurgia , Cauda Equina/cirurgia , Defeitos do Tubo Neural/cirurgia , Siringomielia/cirurgia , Humanos , Procedimentos Neurocirúrgicos/métodos , Escoliose/cirurgia
6.
Protoplasma ; 257(3): 993-1008, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31865451

RESUMO

For the observation of plant material under a light microscope, free-hand sectioning is usually the fastest and most practical procedure. The staining of the obtained cuts is a crucial step and the action mechanism of the dye is variable. Toluidine blue O is a cationic dye whose metachromatic potential for free-hand sections has long been known. Thus, this work aimed at analysing the performance of Toluidine blue O for this type of sectioning with a systematic and comparative approach. The action of Toluidine blue O pH 4.0 was tested for both fresh and previously clarified free-hand sections from leaves of different species of plant. These sections were compared with sections embedded in glycol-methacrylate resin stained with the same dye or submitted to different histochemical tests. The fresh sections obtained by free-hand and stained with Toluidine blue O permitted the accomplishment of histochemical inferences, with the advantage of maintaining the natural colours from the tissues. The previously clarified sections presented the advantage of having a clearer image, allowing a better cellular delimitation. We concluded that Toluidine blue O is very informative for sections of plant material obtained by free-hand, being, therefore, a procedure that is fast, inexpensive and with excellent results.


Assuntos
Histocitoquímica/métodos , Plantas/química , Coloração e Rotulagem/métodos , Cloreto de Tolônio/química
7.
Methods Mol Biol ; 2014: 3-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31197782

RESUMO

In order to successfully analyze and describe any plant tissue, the first challenge is preparation of good anatomical slides. The challenge is even greater when the target tissue has heterogeneous characteristics, such as the phloem where soft and stiff tissues occur side by side. The goal of this chapter is to present a detailed protocol containing various techniques for optimal preparation of phloem tissue samples for light microscopic analysis. The process typically involves the steps of fixation, softening, embedding, sectioning, staining, and mounting. The protocol can be applied to make samples of phloem and surrounding tissues of stems and roots, from woody to herbaceous plants.


Assuntos
Microscopia , Floema/anatomia & histologia , Floema/citologia , Automação Laboratorial , Técnicas de Preparação Histocitológica , Microscopia/métodos , Floema/química
8.
Int. j. morphol ; 36(2): 642-650, jun. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-954166

RESUMO

The aim of this study was to analyze the sexual dimorphism in the mandibles of Jordanians and derive a population specific equation for sex prediction. The employed sample comprised 270 cone beam computed tomography (CBCT) images of Jordanians (147 males and 123 females) aged 27-55 years. The images were rendered to 3D surface models, using customized software that provided various views for each mandible, on which measurements made of nine parameters (ramus height, right and left coronoids height, mandibular length, gonial angle, Intergonial breadth, Intercondylar breadth, mental and mandibular foramena) for the analysis of sex identification. The collected data sets were treated statistically using the Statistical Package SPSS version-21. Canonical discriminant function analysis was used to specify a parameter or combination of parameters that best separate the two sexes. Stepwise analysis together with leave-one-out classification procedure was applied (utilizing the Wilks lambda method), which identified six parameters that formed the best combination most precisely predicting sex. It also identified the predictors' coefficients from which a predictive equation for the Jordanian population was derived. The discriminant function group centroid discriminant scores for males and females and the sectioning cut-score were also defined. According to the equation, the function score for any set of measurements that is above the cut score is probably for a male individual whereas a score that was below the cut score is probably for a female subject.


El objetivo de este estudio fue analizar el dimorfismo sexual en las mandíbulas de los jordanos y derivar una ecuación específica de la población para la predicción del sexo. La muestra consistió en 270 imágenes de tomografía computarizada de haz cónico (CBCT) de jordanos (147 hombres y 123 mujeres) con edades entre los 27 y 55 años. Las imágenes se representaron en modelos de superficie 3D, utilizando software personalizado que proporcionó varias imágenes para cada mandíbula, en las que se midieron nueve parámetros (altura de la rama, altura de los procesos coronoides derecho e izquierdo, longitud mandibular, ángulo gonial, amplitud intergonial, amplitud intercondilar y foramen mandibular) para el análisis de la identificación de sexo. Los conjuntos de datos recopilados se trataron estadísticamente utilizando el programa estadístico SPSS versión-21. El análisis de función discriminante canónica se utilizó para especificar un parámetro, o una combinación de parámetros que separaran mejor los dos sexos. Se aplicó el análisis por pasos junto con el procedimiento de clasificación de dejar salir uno (utilizando el método de Wilks lambda), que identificó seis parámetros que formaban la mejor combinación que predecía con mayor precisión el sexo. También se identificó los coeficientes de los predictores a partir de los cuales se obtuvo una ecuación predictiva para la población jordana. Se definieron además, los puntajes discriminantes centroide del grupo para hombres y mujeres, además del puntaje de corte seccional. De acuerdo con la ecuación, el puntaje de la función para cualquier conjunto de medidas que está por encima del puntaje de corte es probablemente para un individuo masculino, mientras que un puntaje que estaba por debajo del puntaje de corte, probablemente era femenino.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Caracteres Sexuais , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Análise Discriminante , Tomografia Computadorizada de Feixe Cônico , Jordânia
9.
Int. j. morphol ; 35(4): 1525-1539, Dec. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-893165

RESUMO

RESUMEN: El hígado es un órgano sólido, de gran relevancia para la fisiología. Es asiento potencial de lesiones tumorales quísticas y sólidas; benignas y malignas (primarias y secundarias); razón por la cual, conocer su anatomía radiológica y quirúrgica es muy relevante. Los antecedentes históricos comienzan con Berta en 1716, quien fue el primero en realizar una resección hepática; en 1888, Lagenbuch fue el primero el realizar una resección hepática programada. En 1889, Keen realizó la primera lobectomía hepática izquierda, seguido de Webde, en 1910, quien ejecutó la primera lobectomía hepática derecha. Más tarde, Couinaud, en 1957, realizó ua descripción completa de la anatomía segmentaria del hígado, dando una mejor comprensión quirúrgica de la morfología hepática, para su abordaje en distintas patologías. Un hito fundamental en el desarrollo del estudio del hígado, fue el establecimiento de la "Clasificación de Brisbane", por parte del Comité Científico de la Asociación Internacional Hepatobilio-Pancreática, poniendo fin a la confusión terminológica establecida entre los términos franceses y anglosajones. Y desde el ámbito anatómico, se destaca la aparición de Terminologia Anatomica, por parte del Programa Federativo Internacional de Terminologia Anatomica (FIPAT) dependiente de la Federación Internacional de Asociaciones de Anatomistas (IFAA), quienes dentro de la misma, establecieron los términos anatómicos correspondientes al hígado. El objetivo de este manuscrito, es entregar un resumen esquemático de la anatomía quirúrgica y radiológica del hígado, que fundamentan las diferentes opciones de resecciones hepáticas.


SUMMARY: The liver is a solid organ which is most relevant for physiology. It is a potential site for cystic and solid (primary and secondary) benign and malignant tumor lesions. Therefore, thorough knowledge of its radiological and surgical anatomy is important. Historical background of liver resections began with Berta in 1716, who was the first to carry out the procedure. In 1888, Lagenbuch performed the first programmed liver resection and subsequently, in 1889 Keen performed the very first left hepatic lobectomy, followed by Webde in 1910, who performed the first right hepatic lobectomy. Later in 1957, Couinaud recorded a complete description of the segmental anatomy of the liver, providing a greater surgical understanding of the hepatic morphology, for approach in various pathologies. A fundamental milestone in the development of the liver study was the establishment of the "Brisbane Classification" by the Scientific Committee of the International Hepatobiliary-Pancreatic Association, which ended previous confusion between the French and Anglo-Saxon terminology. Furthermore, within the scope of anatomy, the introduction of Terminología Anatómica, by the International Federative Program of Anatomical Terminology (FIPAT) which depends on the International Federation of Associations of Anatomists ( IFAA), established the anatomical terms for the liver The objective of this manuscript is to provide a schematic summary of the surgical and radiological anatomy of the liver, on which the different options for liver resections are based.


Assuntos
Humanos , Hepatectomia , Fígado/anatomia & histologia , Fígado/diagnóstico por imagem , Fígado/cirurgia
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