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1.
Acta sci., Biol. sci ; 45: e63169, 2023. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1427159

RESUMO

Intercellular protuberances (IPs) are projections on the cell surface and have been reported for families of ferns, Gymnosperms, and Angiosperms. Data on the type, chemical composition, and distribution of these structures among vascular plants are still scarce. Here, we investigate the occurrence, distribution, type of IPs among species of eight Dennstaedtiaceae genera and verify the taxonomic significance of these protuberances in the family. Rhizomes of 23 species of Dennstaedtiaceae from field and herbaria collections were analyzed by light microscopy and scanning electron microscopy. Histochemical tests were performed to identify the main classes of IPs chemical compounds. Two types of IPs were observed in Dennstaedtiaceae species: strand and filament types. They were observed in the intercellular spaces of the parenchyma in the cortex and pith regions. Overall, protuberances are irregularly shaped, with angustate or spheroidal apices. Their polysaccharide nature and pectic constitution were confirmed by histochemical tests. Concerning Pteridium arachnoideum (Kaulf.) Maxon subsp. arachnoideum, IPs have confirmed phenolic composition. Evidence indicates that IPs in Dennstaedtiaceae originate from the fragmentation of the middle lamella and that they have a structural function as well as protection against pathogens. In lateral-line aerenchyma, the occurrence of filament-type IPs may be related to the larger intercellular spacing in the cortex region, providing greater mechanical resistance. We have expanded the data on the occurrence of IPs in the Dennstaedtiaceae, which appear to be notable characters for the family. Moreover, the data presented herein confirmed the polysaccharide and pectic nature of these structures. However, we were unable to find links between IPs and taxonomy and evolution of the Dennstaedtiaceae. On the other hand, different IPs types were identified between the clades Dennstaedtioideae (strand-type IPs) and Hypolepidoideae (filament-type IPs, with exceptions).(AU)


Assuntos
Rizoma/química , Dennstaedtiaceae/anatomia & histologia , Imuno-Histoquímica/métodos
2.
Protoplasma ; 258(5): 963-977, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33651219

RESUMO

Phytomelanin is a brown to black pigment found in plant tissues, mainly in Asparagales and Asteraceae species. However, few studies deal with the processes of its synthesis, and there are still many questions to be answered regarding the organelles involved in this process and their functions, especially in vegetative organs. In a previous study with stems and leaves of 77 Vernonieae (Asteraceae) species, phytomelanin was demonstrated to always be associated with sclereids, which suggests the involvement of these cells in the pigment synthesis. Thus, we selected another species of tribe Vernonieae, Piptocarpha axillaris (Less.) Baker, which produces abundant phytomelanin secretion in stem tissues, to investigate which cells and organelles are involved in the synthesis and release of this pigment, as well as its distribution in the tissues. To achieve this goal, stems in different developmental phases were analyzed under light and transmission electron microscopy. Anatomical analysis showed that the polymerization of phytomelanin in P. axillaris starts at the second stem node, in the pith region, and occurs simultaneously with sclereid differentiation. The plastids of cells that will differentiate into sclereids actively participate in the phenolic material synthesis, following the "tannosome" and the "pearl necklace" models, giving rise to the main precursor of phytomelanin, which is then polymerized in the intercellular spaces during the sclerification process of sclereids. In stems with an established secondary structure, the pigment can be observed more frequently in the cortex, pericycle, primary phloem, secondary phloem, and pith.


Assuntos
Asteraceae , Floema , Folhas de Planta , Caules de Planta , Plantas , Plastídeos
3.
Clinics (Sao Paulo) ; 64(7): 669-74, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19606244

RESUMO

UNLABELLED: The purpose of this study was to compare esophageal infusion with 0.1 N hydrochloric acid (HCl) to esophageal infusion with saline in patients presenting with typical gastroesophageal reflux symptoms and erosive esophagitis. METHODS: Upper gastrointestinal endoscopy was performed on 44 prospective subjects, 29 of whom were included in the study. Eighteen patients presented with normal esophagi (Control Group "C"), nine of whom were infused with HCl and nine with saline. Eleven patients presented with erosive esophagitis (Lesion Group "L"), five of whom were infused with HCl and six with saline. Biopsies of the esophageal mucosa were collected before and after infusions. RESULTS: No statistically significant difference was found between the two types of infusions in terms of the dilation of the intercellular space of the esophageal epithelium, regardless of the status of the patient. CONCLUSIONS: Response to HCl infusion cannot be used as a marker for gastroesophageal reflux disease.


Assuntos
Esofagite/patologia , Esôfago/efeitos dos fármacos , Espaço Extracelular/efeitos dos fármacos , Refluxo Gastroesofágico/patologia , Ácido Clorídrico , Cloreto de Sódio , Adolescente , Adulto , Idoso , Biópsia , Epitélio/patologia , Esôfago/patologia , Feminino , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade , Mucosa/efeitos dos fármacos , Mucosa/patologia , Estudos Prospectivos , Adulto Jovem
4.
Rev. colomb. quím. (Bogotá) ; 38(1): 43-59, abr. 2009. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-636644

RESUMO

En este trabajo se analizó el líquido de lavado intercelular de Lycopersicon escu-lentum ceraciforme L1568 perteneciente al germoplasma nacional con resistencia en campo a P. infestans el cual mostró la presencia de cuatro ß (1,3) glucanasas después de infección con el patógeno. Para tal efecto las plantas se inocularon con el patógeno con el fin de inducir aumento en la concentración de las proteínas PR y otras sustancias relacionadas con defensa; 15 días después de la inoculación con el parásito, se extrajo el líquido de lavado intercelular de las hojas de tomate utilizando agua. Las proteínas con actividad de ß (1,3) glucanasa extraídas se liofilizaron, se resuspendieron en búfer, se purificaron utilizando cromatografía de exclusión, intercambio iónico y electroforesis preparativa. Los resultados de caracterización parcial, mostraronlaexistenciadeuna ß (1,3) glucanasa básica con peso molecular de 36,8 kDa y pI 9,2 y tres ß (1,3) glucanasas ácidas de 35,4; 30,1 y 7,2 kDa con puntos isoeléctricos de 3,8; 3,6 y 5,0 respectivamente. Adicionalmente se determinaron las propiedades cinéticas de cada enzima, KM, Vmáx,Eo yK3 encontrando, de acuerdo con los resultados obtenidos, que la proteína básica no ha sido reportada en la literatura relacionada con tomate.


In this paper was analysed the intercellular washing fluid of Lycopersicon esculentum ceraciforme L1568 belonging to the national germplasm with resistance to P. infestans in field which showed the presence of four ß (1,3) glucanases after infection with the pathogen. For this purpose the plants were inoculated with the pathogen to induce a concentration increase of PR proteins and other defence-related substances, 15 days after inoculation with the parasite was extracted the intercellular washing fluid of tomato leaves using water. The proteins with ß(1,3) glucanase activity were extracted, freeze-dried and re-suspended in buffer solution and were purified using exclusion chromatography, ion exchange chromatography and preparative electrophoresis. The results of partial characterization showed the presence of a basic ß (1,3) glucanase with a molecular weight of 36.8 kDa and pi 9.2 and three ß (1,3) glu-canase acid 35.4, 30.1 and 7.2 kDa with isoelectric points of 3.8, 3.6 and 5.0 respectively. Additionally it was determined the kinetic properties of each enzyme, KM,Vmax, and Eo,K3, according to the results, the basic protein has not been reported in the literature related to tomato.


Este trabalho analisou o líquido de lavado intercelular de Lycopersicon esculentum ceraciforme L1568 pertencente ao ger-moplasma nacional com resistência em campo a P. infestans, mostrau a presença de quatro ß (1,3) glucanase despois a infecção com o agente patogênico. Para este efeito as plantas foram inoculadas com o agente patogénico para induzir um aumento na concentração das proteínas PR y outras substâncias relacionadas com defesa, e 15 dias mais tarde se extraiu o líquido de lavado intercelular de folhas de tomate utilizando água. As proteínas extraídas foram liofilizadas, resuspendidas em solução tampão, purificadas utilizando cromatografia de exclusão, de intercambio iónico e electroforesepreparativa,. Os resultados da caracterização paracial revelou a existência de uma ß(1,3) glucanasa basica com peso molecular de 36,8 kDa e PI 9,2, e três ß(1,3) glucanasas ácidas de 35.4, 30.1 e 7.2 kDa com pontos isoeléctricos de 3.8, 3.6y 5.0, respectivamente. Adicionalmente, foi possível determinar as propriedades cinéticas KM,Vmax,Eo yK3 de cada enzima, encontrando de acordo com os resultados que a proteína básica não havia sido reportada na literatura.relacionada com tomate.

5.
Clinics ; Clinics;64(7): 669-674, 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-520800

RESUMO

The purpose of this study was to compare esophageal infusion with 0.1 N hydrochloridric acid (HCl) to esophageal infusion with saline in patients presenting with typical gastroesophageal reflux symptoms and erosive esophagitis. METHODS: Upper gastrointestinal endoscopy was performed on 44 prospective subjects, 29 of whom were included in the study. Eighteen patients presented with normal esophagi (Control Group "C"), nine of whom were infused with HCl and nine with saline. Eleven patients presented with erosive esophagitis (Lesion Group "L"), five of whom were infused with HCl and six with saline. Biopsies of the esophageal mucosa were collected before and after infusions. RESULTS: No statistically significant difference was found between the two types of infusions in terms of the dilation of the intercellular space of the esophageal epithelium, regardless of the status of the patient. CONCLUSIONS: Response to HCl infusion cannot be used as a marker for gastroesophageal reflux disease.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Esofagite/patologia , Esôfago/efeitos dos fármacos , Espaço Extracelular/efeitos dos fármacos , Refluxo Gastroesofágico/patologia , Ácido Clorídrico , Cloreto de Sódio , Biópsia , Epitélio/patologia , Esôfago/patologia , Microscopia Eletrônica , Mucosa/efeitos dos fármacos , Mucosa/patologia , Estudos Prospectivos , Adulto Jovem
6.
Rev. colomb. quím. (Bogotá) ; 34(1): 7-23, jun. 2005. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-636565

RESUMO

Se aislaron y caracterizaron parcialmente proteínas antifúngicas de los espacios intercelulares de hojas de tomate Lycopersicon esculentum cerasiforme, variedad que ha mostrado resistencia en campo a Phytophthora Infestans; se observó que después de inoculación con el patógeno dichas proteínas se acumularon sistémicamente en la planta. Las proteínas identificadas mostraron características de Defensinas de plantas, una nueva familia de proteínas con bajo peso molecular, carga positiva a pH fisiológico y actividad antifúngica evaluada in vitro contra P. infestans. Los análisis electroforéticos en geles de poliacrilamida con SDS-Tricina en condiciones reductoras y no reductoras, sugirieron que están asociadas en trímeros y tetrámeros y poseen pesos moleculares de 5,2 kDa.


Antifungal Proteins from intercellular space of Tomato leaves Lycopersicon esculentum cerasiforme were isolated and partially characterized; this variety had shown resistance against Phytophthora infestans, after inoculating plants with the pathogen it was observed that these proteins were accumulated systemically. The isolated proteins be haved as plant defensins, a novel protein family, with low molecular weight, cationics at physiological pH and Antifungal Activity in vitro evaluated against P. infestans. Electrophoretic analyses in SDS Tricine-PAGE, under reducing and non-reducing conditions suggested that, they were associated as trimers and tetramers; and have molecular weights of 5,2 kDa.

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