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1.
J Plant Res ; 135(4): 593-608, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35641669

RESUMEN

Plant galls are generated by the stimuli of gall-inducing organisms on their hosts, creating gall morphotypes that vary in color, shape, size, and tissue organization. Herein, we propose to compare the structural features of gall morphotypes on the superhost Croton floribundus (Euphorbiaceae) in order to recognize gall morphospecies, i.e., galls with similar shapes but different internal structures. Non-galled leaves and galls were analyzed macroscopically, histologically, and histochemically for the detection of primary metabolites, and the results obtained were used for statistical analyses of similarity. Among the eight gall morphospecies, four are globoid, two are lenticular, one is fusiform and one is marginal leaf rolling. Stomatal differentiation and the occurrence of different types of trichomes were impaired in some gall morphospecies. Three patterns of organization of the ground system are recognized, ranging from the maintenance of mesophyll cells that differentiate into palisade and spongy cells dorsiventrally to the formation of a complex cortex with three morphofunctional layers. The marginal leaf rolling galls have the simplest anatomical structures, quite similar to those of the non-galled host leaf, while lenticular, globoid (types I to IV), and fusiform galls are anatomically more complex. Herein, we report on eight gall morphospecies occurring on C. floribundus, which are distinguished by morpho-anatomical attributes and show the disruption of the morphogenetic patterns of the host leaf toward the morphogenesis of unique gall features.


Asunto(s)
Fabaceae , Tumores de Planta , Hojas de la Planta
2.
Mycoses ; 61(8): 587-593, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29663530

RESUMEN

Paracoccidioidomycosis (PCM) is the most prevalent systemic mycosis among immunocompetent patients in Latin America. This study aimed to describe the expansion over time and the geographical distribution of confirmed Neuroparacoccidioidomycosis (NPCM) and PCM cases, and relate it to environmental characteristics such as climate, soil types and coffee crops. This was a retrospective study of autopsy and biopsy reports between 1951 and 2014 from the Medical Pathology Section of the Hospital de Clinicas, Universidade Federal do Paraná (UFPR), Curitiba, Southern Brazil. PCM was predominant in male agricultural workers. PCM cases predominated in areas with subtropical climate with hot summers in North West Parana state. NPCM cases were distributed statewide more frequent in rural than metropolitan area. There was no association with climate, soil type, or coffee crop culture. Most of the PCM cases were in the metropolitan area of the capital, chiefly due to migration fluxes. Even though the history is predominantly agricultural, PCM cases were distributed mainly in the metropolitan area of the state capital, there was no association with climate and soil. NPCM cases were numerically more frequent in rural than metropolitan area.


Asunto(s)
Infecciones Fúngicas del Sistema Nervioso Central/epidemiología , Paracoccidioidomicosis/epidemiología , Topografía Médica , Adulto , Brasil/epidemiología , Clima , Exposición a Riesgos Ambientales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Exposición Profesional , Prevalencia , Estudios Retrospectivos , Población Urbana
3.
Disabil Rehabil Assist Technol ; 16(5): 556-560, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-31686579

RESUMEN

OBJECTIVES: Elderly amputees are a specific clientele because of the interaction of this disease with the ageing process. The objective of this study was to determine the impact of prosthesis rehabilitation on the functional capacity of elderly with lower-limb amputation (LLA) in short and long time. MATERIALS AND METHODS: A quasi-experimental study was developed. The sample consisted of 29 elderly with LLA who finished the prosthesis rehabilitation programme. Gait capacity was evaluated by Functional Ambulation Classification Scale (FAC), ability to perform basic activities of daily living (ADL) was evaluated by Barthel Index (BI) and Pfeffer Questionnaire was used to evaluate the capacity to execute instrumental ADL. Statistical inference was done by t-test, t-student test and chi-squared test. The significance level was fixed at 5% (p < 0.05). RESULTS: In the transtibial group (n = 15) no difference (p = 0.108) was found between BI score before amputation and after 3 months of follow up. The transfemoral group (n = 14) improved significantly (p = 0.045) the FAC before starting and after 3 months of discharge from ambulatory rehabilitation. Both groups increased the time of prosthesis use during the day after 3 months of follow up. However, no group has achieved FAC and Pfeffer Questionnaire pre-amputation performance. CONCLUSION: Although elderly with LLA improved functional capacity after 3 months of a prosthesis rehabilitation programme, they did not achieve their pre-amputation functionality.Implications for rehabilitationLower-limb amputation causes a significant socioeconomic impact and decreases functional capacity, autonomy and quality of life. Elderly people with a lower-limb amputation impose a heavy burden on health resources, requiring extensive rehabilitation and long term care. The specific presentation of elderly persons with lower-limb amputation, with multiple physical, psychological, cognitive, and social comorbidities, imposes unique challenges to ongoing care. The potential bias from the inclusion of younger patients into a study with an elderly population with lower-limb amputation supports the need for independent investigation.In our study we verified that although elderly with transfemoral or transtibial amputation have improved their functional independence after lower-limb prosthesis rehabilitation, they could not achieve their functional capacity before amputation. This improvement especially occurred for the basic activities of daily living, however elderly patients with transfemoral amputations presented greater difficulty in improving functional capacity.These results support that being able to better select elderly by their mobility potential and environmental barriers, is an important goal for future research to aim toward those who will achieve and maintain prosthetic walking or those who could better focus on regaining nonprosthetic mobility.


Asunto(s)
Amputados , Miembros Artificiales , Actividades Cotidianas , Anciano , Amputación Quirúrgica , Humanos , Estudios Longitudinales , Extremidad Inferior/cirugía , Calidad de Vida
4.
Plant Physiol Biochem ; 146: 457-462, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31821930

RESUMEN

In an altitudinal Brazilian ecosystem, fog is a frequent event in both the dry and rainy seasons. The drought stress is aggravated in the dry season due to elevated evaporative demand and this constraint can induce oxidative stress in plants. In this ecosystem, there are plants which present different foliar water uptake (FWU) capacities - species that absorb less water more quickly (LQ) and those that absorb more water more slowly (MS). In this study, the relationship between oxidative stress responses and the different FWU strategies was evaluated in dry and rainy seasons. The oxidative stress was assessed by H2O2 production and lipid peroxidation as well as by the antioxidant enzymes system as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). During the dry season, plants had higher oxidative stress compared to rainy season plants which exhibited moderate oxidative damage. The FWU strategies were closely related to oxidative stress responses, since the LQ species presented the higher H2O2 content and oxidative defense system. Contrastingly, it was found that MS species have the lowest values of H2O2 and less SOD, CAT and APX activities. However, the lipid peroxidation did not present any relation with FWU strategies. Altogether results revealed that plants, which present MS strategy, are more adapted to cope with the higher H2O2 concentrations generated in the dry season and drought stress events than those that present LQ strategy.


Asunto(s)
Estaciones del Año , Antioxidantes , Ascorbato Peroxidasas , Brasil , Catalasa , Ecosistema , Peróxido de Hidrógeno , Peroxidación de Lípido , Estrés Oxidativo , Superóxido Dismutasa , Agua
5.
Plant Physiol Biochem ; 153: 64-71, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32480237

RESUMEN

Root growth is reduced in soils with low pH [H+] and abundant soluble aluminum [Al3+], which can be a consequence of the interaction between Al3+ and cell wall composition. The competition between Al3+ and Ca2+ toward binding to pectin molecules was evaluated in roots of Urochloa decumbens, an African grass highly adapted to acidic Al-rich soils. Variations in the composition and distribution of pectins can change the extensibility, rigidity, porosity, and adhesive properties of plant cell walls, which were tested in seedlings of U. decumbens exposed to pH 3.5, 4.5 and 5.8 and to 0, 80, 160 and 320 µM of Al3+ for 80h. Root growth corroborated that U. decumbens is very tolerant to soil acidity, with effective reduction of root growth only at pH 3.5. Immunocytochemical approaches demonstrated variations in pectin composition induced both by Al3+ and by H+ in root tissues and zones. Based on the usual linkage between Ca2+ and pectins, Density Functional Theory (DFT) analyses indicated that Al3+ bound easier to pectins than Ca2+ did, leading to the formation of more Al3+-pectate complexes than Ca2+-pectate complexes, which resulted in higher rigidity of cell walls, and hampered cell extension.


Asunto(s)
Aluminio/metabolismo , Calcio/metabolismo , Pectinas/metabolismo , Raíces de Plantas/metabolismo , Poaceae/metabolismo , Pared Celular , Teoría Funcional de la Densidad , Inmunohistoquímica
6.
Plant Physiol Biochem ; 156: 445-460, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33022481

RESUMEN

Most seeds store reserves, which mobilization after germination is complex and diversified among plant species. Information on the reserve mobilization in recalcitrant seeds (i.e., intolerant to desiccation) is scarce. The aim of this work was to characterize the dynamics of reserve mobilization and the degradation pattern of the endospermic cell walls in the recalcitrant seeds of the neotropical palm Mauritia flexuosa. Biometric, anatomical, histochemical, ultrastructural and immunocytochemistry assessments were performed in the endosperm and haustorium (structure of the seedling involved in reserve mobilization), during germination and throughout seedling development. Endo-ß-mannanase activity was assessed. The main reserves stored in the seeds are mucilage in the living protoplast and, mainly, heteromannans in the thick cell walls of the endosperm cells. The reserve mobilization extends for about 180 days, in four phases. During germination, the embryonic reserves are catabolized, which induces the mobilization of the endosperm by establishing the flow of water and carrying substances to the haustorium. After germination, the cells of the endosperm actively control the process of their degradation, which results in the formation of the digestion zone. The growth of the haustorium promotes the crushing of endospermic cells and facilitates the entry of substances via the apoplastic route. The pattern of degradation of endospermic cells involves three phases: 1) mobilization of the vacuolar content by symplastic route; 2) increased vacuole turgor pressure, directing the content of the cytoplasm to the cell walls; 3) degradation of cell walls.


Asunto(s)
Arecaceae , Pared Celular/química , Germinación , Mananos/química , Semillas/fisiología , Semillas/química
7.
Talanta ; 175: 9-20, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28842040

RESUMEN

A headspace solid phase microextraction (HS-SPME) method combined with gas chromatography-mass spectrometry (GC/MS) was developed and optimized for extraction and analysis of volatile organic compounds (VOC) of leaves and galls of Myrcia splendens. Through a process of optimization of main factors affecting HS-SPME efficiency, the coating divivnilbenzene-carboxen-polydimethylsiloxane (DVB/Car/PDMS) was chosen as the optimum extraction phase, not only in terms of extraction efficiency, but also for its broader analyte coverage. Optimum extraction temperature was 30°C, while an extraction time of 15min provided the best compromise between extraction efficiencies of lower and higher molecular weight compounds. The optimized protocol was demonstrated to be capable of sampling plant material with high reproducibility, considering that most classes of analytes met the 20% RSD FDA criterion. The optimized method was employed for the analysis of three classes of M. splendens samples, generating a final list of 65 tentatively identified VOC, including alcohols, aldehydes, esters, ketones, phenol derivatives, as well as mono and sesquiterpenes. Significant differences were evident amongst the volatile profiles obtained from non-galled leaves (NGL) and leaf-folding galls (LFG) of M. splendens. Several differences pertaining to amounts of alcohols and aldehydes were detected between samples, particularly regarding quantities of green leaf volatiles (GLV). Alcohols represented about 14% of compounds detected in gall samples, whereas in non-galled samples, alcohol content was below 5%. Phenolic derived compounds were virtually absent in reference samples, while in non-galled leaves and galls their content ranged around 0.2% and 0.4%, respectively. Likewise, methyl salicylate, a well-known signal of plant distress, amounted for 1.2% of the sample content of galls, whereas it was only present in trace levels in reference samples. Chemometric analysis based on Heatmap associated with Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) provided a suitable tool to differentiate VOC profiles in vegetal material, and could open new perspectives and opportunities in agricultural and ecological studies for the detection and identification of herbivore-induced plant VOC emissions.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Myrtaceae/química , Hojas de la Planta/química , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/análisis , Alcoholes/análisis , Aldehídos , Diseño de Equipo , Ésteres/análisis , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Cetonas/análisis , Fenoles/análisis , Microextracción en Fase Sólida/instrumentación , Temperatura
8.
Rev. biol. trop ; Rev. biol. trop;61(3): 1053-1065, sep. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-688459

RESUMEN

The survival of plants in epiphytic environments depends on vegetative adaptations capable to defraud different stresses. Based on the structural diversity of the Orchidaceae, the current study has the objective of relating the anatomical structure of Dichaea cogniauxiana and Epidendrum secundum with the distinct environments where they live. It was expected that, despite structural similarities as strategies for resource acquisition, some peculiar variations related to the distinct light microenvironments (inside or in the edge of the nebular forest, near to “campo rupestre” area) might be found. Leaves and roots of both species were collected in a nebular forest located at a “campo rupestre” area at Serra da Piedade, Brazil), in January and February 2005. D. cogniauxiana is adhered to trunks, in sites with high atmospheric humidity and shaded, while E. secundum is located at the edge of the nebular forest, in more luminous sites. The leaves of E. secundum had thicker cuticle and higher number of stomata per area than those of D. cogniauxiana, characteristics coherent with their distinct pattern of exhibition to sun light. The suprastomatic chambers formed by the thicker cuticle may function as a barrier of resistance to water evaporation. The succulence of the leaves of E. secundum propitiates organic acids storage at night, and the storage of starch may be involved in PEP-carboxylase metabolism, both propitiating CAM mechanism. Roots with larger number of cell layers of the velamen, and specialized thick walled cortical cells (both in E. secundum) help water absorption and indicate better adaptation to an environment with intense solar radiation and a probable higher water deficit. The remarkable cell wall thickening of E. secundum exodermis can confer more efficient protection against the excess of transpiration at the border of the nebular forest. On the other hand, besides D. cogniauxiana be epiphyte, it is in a low position - in a shaded environment and with high relative humidity. Its thin thickened velamen permits the entrance of the low available light, and photosynthesis, producing oxygen and helping to avoid hypoxia condition. As features registered for D. cogniauxiana and E. secundum roots, we can depict the velamen, distinct exodermis and endodermis, and specialized thick walled cortical cells as characteristic of epiphytic plants.


La sobrevivencia de las plantas epífitas a su ambiente depende de las adaptaciones vegetativas que les permiten afrontar diferentes tipos de estrés. Basado en la diversidad estructural de las Orchidaceae, el presente estudio tiene por objetivo relatar la estructura anatómica de Dichaea cogniauxiana y Epidendrum secundum con relación a los distintos ambientes donde viven. Hojas y raíces fueron recolectados en un bosque nuboso de un campo rupestre en la Serra da Piedade, Brasil. Dichaea cogniauxiana está adherida a los troncos, en sitios con alta humedad atmosférica y sombra, mientras que E. secundum está localizada en el margen del bosque nebular, en sitios más iluminados. Las hojas de E. secundum tienen una cutícula más gruesa y un mayor número de estomas por área que las de D. cogniauxiana, características coherentes con los diferentes patrones de exhibición a la luz del sol. Las cámaras supraestomáticas formadas por la cutícula pueden funcionar como una barrera de resistencia a la evaporación del agua. La suculencia de las hojas de E. secundum propicia el almacenamiento de ácidos orgánicos por la noche, y el almacenamiento de almidón puede estar implícito en el metabolismo de la PEP-carboxilasa. Las raíces con mayor velamen y especializadas paredes gruesas de las células corticales (ambas en E. secundum) ayudan a la absorción e indican una mejor adaptación al ambiente con intensa radiación solar y probable alto déficit de agua. El engrosamiento de la pared celular en la exodermis de E. secundum puede conferir una protección más eficaz contra el exceso de transpiración en el margen del bosque nebular. Por otra parte, D. cogniauxiana además de ser epífita, está en una posición baja, en un ambiente sombreado y con una alta humedad relativa. Su velamen delgado permite la entrada de la baja luz disponible y la fotosíntesis, produciendo oxígeno que ayuda a evitar la condición hipóxica.


Asunto(s)
Adaptación Fisiológica/fisiología , Ecosistema , Orchidaceae/fisiología , Árboles , Brasil , Orchidaceae/clasificación , Fotosíntesis/fisiología , Epidermis de la Planta/fisiología , Hojas de la Planta/fisiología , Simpatría
9.
Rev. biol. trop ; Rev. biol. trop;57(1/2): 293-302, March-June 2009. ilus
Artículo en Inglés | LILACS | ID: lil-637719

RESUMEN

Gall inducing insects most frequently oviposit in young tissues because these tissues have higher metabolism and potential for differentiation. However, these insects may also successfully establish in mature tissues as was observed in the super-host Copaifera langsdorffii. Among C. langsdorffii gall morphotypes, one of the most common is a midrib gall induced by an undescribed species of Cecidomyiidae. Following this ‘host plant and gall-inducing insect’ model, we addressed two questions: 1) Do the age of the tissues alter the gall extended phenotype? 2) Do gall morphological and anatomical features influence the adaptive value of the galling insect? For anatomical and histometrical studies, transverse sections of young and mature, galled and ungalled samples were prepared. Galls in young leaflets presented higher potential for cell division and greater nutritive reserves, whereas galls in mature leaflets perhaps provide more protection against natural predators and desiccation. Host organ age at the time of oviposition may influence plant cell fates and consequently the interpretation of the adaptive value of insect galls. Rev. Biol. Trop. 57 (1-2): 293-302. Epub 2009 June 30.


Asunto(s)
Animales , Fabaceae/parasitología , Hojas de la Planta/parasitología , Tumores de Planta/parasitología , Fabaceae/anatomía & histología , Fabaceae/clasificación , Interacciones Huésped-Parásitos , Insectos/fisiología , Hojas de la Planta/anatomía & histología , Hojas de la Planta/citología , Factores de Tiempo
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