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1.
Front Plant Sci ; 14: 1198197, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426986

RESUMO

[This corrects the article DOI: 10.3389/fpls.2022.971235.].

2.
Front Plant Sci ; 13: 971235, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262651

RESUMO

Laticifers are secretory structures that produce latex, forming a specialized defense system against herbivory. Studies using anatomical approaches to investigate laticifer growth patterns have described their origin; however, their mode of growth, i.e., whether growth is intrusive or diffuse, remains unclear. Studies investigating how cytoskeleton filaments may influence laticifer shape establishment and growth patterns are lacking. In this study, we combined microtubule immunostaining and developmental anatomy to investigate the growth patterns in different types of laticifers. Standard anatomical methods were used to study laticifer development. Microtubules were labelled through immunolocalization of α-tubulin in three types of laticifers from three different plant species: nonanastomosing (Urvillea ulmacea), anastomosing unbranched with partial degradation of terminal cell walls (Ipomoea nil), and anastomosing branched laticifers with early and complete degradation of terminal cell walls (Asclepias curassavica). In both nonanastomosing and anastomosing laticifers, as well as in differentiating meristematic cells, parenchyma cells and idioblasts, microtubules were perpendicularly aligned to the cell growth axis. The analyses of laticifer microtubule orientation revealed an arrangement that corresponds to those cells that grow diffusely within the plant body. Nonanastomosing and anastomosing laticifers, branched or not, have a pattern which indicates diffuse growth. This innovative study on secretory structures represents a major advance in the knowledge of laticifers and their growth mode.

3.
Plants (Basel) ; 10(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34834691

RESUMO

Stinging trichomes are rare in plants, occurring only in angiosperms, where they are reported for a few genera belonging to six families. Although there is no report of stinging trichomes in Apocynaceae, previous fieldwork collections of Fischeria and Matelea caused us a mild allergic reaction on the skin when we contacted the dense indumentum of the plants. This fact associated with the well-known presence of glandular trichomes with acute apex in both genera raised suspicions that stinging trichomes could be present in the family. Hence, this study aimed to investigate the likely occurrence of stinging trichomes in Fischeria and Matelea. We analyzed vegetative shoots and leaves of Fischeria stellata and Matelea denticulata through the usual procedures of light and scanning electron microscopy. We also performed several histochemical tests to investigate the chemical composition of trichome secretion. We detected that glandular trichomes occur throughout the surface of the leaf and stem. They are multicellular, uniseriate with an apical secretory cell, which has a dilated base and a needle-shaped apex. The secretion is compressed into the acuminate portion of the apical cell by a large vacuole, and crystals are deposited in the cell wall in a subapical position, providing a preferential site of rupture. The secretion, composed of amino acids and/or proteins, is released under mechanical action, causing skin irritation. Based on our detailed morphological and anatomical analyses, and in the functional aspects observed, we concluded that the glandular trichomes in Fischeria and Matelea can indeed be classified as stinging. Thus, Apocynaceae is the seventh family for which this type of trichome has been reported. We also compiled information on stinging trichomes in all families of angiosperms. Their phylogenetic distribution indicates that they have evolved at least 12 times during angiosperm evolution and may represent an evolutionary convergence of plant defense against herbivory.

4.
Front Plant Sci ; 12: 669585, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777088

RESUMO

[This corrects the article DOI: 10.3389/fpls.2020.612985.].

5.
Front Plant Sci ; 11: 612985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33537047

RESUMO

Laticifer occurrence and structure are poorly known in Sapindaceae. Occurrence is likely underestimated owing to the low production of latex in most species. We investigated 67 species from 23 genera of Sapindaceae to verify laticifer occurrence and their structural, developmental and chemical features, as well as their evolutionary history in the family. Shoots were collected from herbarium and fresh specimens for histological analyses. Three characters derived from laticifer features were coded and their ancestral states reconstructed through Bayesian stochastic mapping and maximum likelihood estimation. Only articulated non-anastomosing laticifers were found in Sapindaceae. Laticifers differentiate early during shoot development and are found in the cortex, phloem, and pith. Latex is mostly composed of lipids. Callose and suberin were detected in laticifer cell walls in some genera. Reconstruction of laticifer ancestral states showed that laticifers are present in most clades of Sapindaceae with some reversals. Callose in the laticifer cell wall was found exclusively in Serjania and Paullinia (tribe Paullinieae), a character regarded as independently derived. Occurrence of laticifers in Sapindaceae is broader than previously reported. Articulated non-anastomosing laticifers had five independent origins in Sapindaceae with some secondary losses, occurring in five out of six genera of Paullinieae and 10 other genera outside Paullinieae. Particularly, callose in the laticifer cell wall evolved independently twice in the family, and its occurrence may be interpreted as a key-innovation that promoted the diversification of Paullinia and Serjania. Our study suggests that laticifer characters may be useful in understanding the generic relationships within the family.

6.
An Acad Bras Cienc ; 89(3 Suppl): 2399-2410, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29069136

RESUMO

Wild plant species with potential for use as ornamental green foliage are often reported. Nevertheless, there are few studies evaluating morphological and anatomical aspects associated with this use. Preliminary trials suggest that the species of Sphaeradenia (Sander ex Mast.) Harling, a Cyclantaceae that occurs from Costa Rica to Peru, is suitable to be used as fresh foliage because of attractiveness of their leaves in vase and its durability without showing tissue damage, compared with other genera of this family. Through the study of anatomical characters, it is possible to predict the potential of a species that can serve as ornamental foliage. In this study, three foliar anatomical features (thickness of the cuticle and leaf, and percentage of fibers in the mesophyll) of seven Cyclanthaceae species were evaluated, using anatomical techniques and image analysis with the LUCIA® and ImageJ softwares. Statistical analysis of the results suggests that this high durability is associated with the thickness of the cuticle and mesophyll, but not with the amount of fibers in the leaf.


Assuntos
Folhas de Planta/anatomia & histologia , Fenômenos Fisiológicos Vegetais , Células do Mesofilo , Folhas de Planta/fisiologia
7.
Rev. colomb. radiol ; 28(3): 4486-4488, 2017. ilus
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-986738

RESUMO

El bezoar es una concreción que se forma en la luz del tracto gastrointestinal por la acumulación de cuerpos extraños no digeribles. Se clasifican de acuerdo con el material que los componen, son el tricobezoar y el fitobezoar las formas más frecuentes, los cuales están compuestos de pelo y de fibras de vegetales y frutas, respectivamente. El bezoar usualmente se forma en el estómago, puede pasar al intestino delgado (síndrome de Rapunzel) y ser una causa poco frecuente de obstrucción intestinal. En este artículo se describe un caso de tricobezoar gástrico, sus hallazgos por imagen, patología y una breve revisión de la literatura. La información acerca de esta entidad es limitada y se cuenta con pocas series de casos por lo cual es necesario continuar describiendo y determinando sus hallazgos en las diferentes modalidades diagnósticas.


A bezoar is a foreign body that can form in the gastrointestinal tract due to the ingestion of non digestible substances. They are classified according to their composition, with trichobezoar and phytobezoar being the most frequent forms, and they are formed by hair and vegetable and fruits fibres respectively. A bezoar is usually formed in the stomach but can however move to the small intestine (Rapunzel syndrome) and become a low frequency cause of intestinal obstruction (0.4 to 4%). This article describes a case of gastric trichobezoar, its findings by image, pathology and a brief review of the literature. The information about this entity is limited and there are few series of cases so it is necessary to continue describing and determining their findings in the different diagnostic modalities.


Assuntos
Humanos , Bezoares , Tomografia Computadorizada Multidetectores , Intestino Delgado
8.
An. acad. bras. ciênc ; 89(3,supl): 2399-2410, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886800

RESUMO

ABSTRACT Wild plant species with potential for use as ornamental green foliage are often reported. Nevertheless, there are few studies evaluating morphological and anatomical aspects associated with this use. Preliminary trials suggest that the species of Sphaeradenia (Sander ex Mast.) Harling, a Cyclantaceae that occurs from Costa Rica to Peru, is suitable to be used as fresh foliage because of attractiveness of their leaves in vase and its durability without showing tissue damage, compared with other genera of this family. Through the study of anatomical characters, it is possible to predict the potential of a species that can serve as ornamental foliage. In this study, three foliar anatomical features (thickness of the cuticle and leaf, and percentage of fibers in the mesophyll) of seven Cyclanthaceae species were evaluated, using anatomical techniques and image analysis with the LUCIA® and ImageJ softwares. Statistical analysis of the results suggests that this high durability is associated with the thickness of the cuticle and mesophyll, but not with the amount of fibers in the leaf.


Assuntos
Fenômenos Fisiológicos Vegetais , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Células do Mesofilo
9.
J Clin Apher ; 30(6): 347-52, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25708454

RESUMO

INTRODUCTION: Therapeutic plasma exchange (TPE) is an extracorporeal blood purification therapy that is part of the treatment of various diseases. Plasma and blood cells can be separated by centrifugation or using membrane separators. MATERIALS AND METHODS: A descriptive analysis, in which the first 500 TPE sessions using membrane filtration without anticoagulation of the extracorporeal circuit are described. RESULTS: Five hundred (500) TPE sessions were performed on 68 patients over a period of 5 years. Therapeutic indications were 17 different diseases. 5% albumin was the most frequent replacement solution used in 62% of sessions. The mean number of plasma volume replacements was 1.33. Complications occurred in 7.6% of the sessions. Arterial hypotension was the most common event and clotting of the extracorporeal circuit was documented in just one TPE session. Electrolyte tests performed in patients during the procedure showed: 11% hypocalcemia, with a similar distribution of hypokalemia. Twenty-two percent (22%) and 37% of phosphorus and magnesium records, respectively, were higher than normal. No symptoms associated with electrolyte abnormalities were documented. CONCLUSIONS: TPE by membrane filtration is one of the techniques by which it is possible to perform such therapy. In this registry, a low rate of complications was documented. While the need for anticoagulation may be related not only to clotting of the circuit but also to the efficiency of the therapy, clinical response in this series of patients was as expected for each disease. Continuous monitoring and an individualized analysis of electrolytes should be performed in TPE patients.


Assuntos
Troca Plasmática/métodos , Centros Médicos Acadêmicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Remoção de Componentes Sanguíneos , Colômbia , Feminino , Filtração/instrumentação , Filtração/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Troca Plasmática/efeitos adversos , Troca Plasmática/instrumentação , Sistema de Registros , Estudos Retrospectivos , Adulto Jovem
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