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1.
Plants (Basel) ; 11(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36501341

RESUMO

Wood properties and agronomic traits associated with fast growth and frost tolerance make Eucalyptus nitens a valuable forest alternative. However, the rapid age-related decline in the adventitious root (AR) formation (herein, meaning induction, initiation, and expression stages) limits its propagation. We analyzed transcriptomic profile variation in leaves and stem bases during AR induction of microcuttings to elucidate the molecular mechanisms involved in AR formation. In addition, we quantified expressions of candidate genes associated with recalcitrance. We delimited the ontogenic phases of root formation using histological techniques and Scarecrow and Short-Root expression quantification for RNA sequencing sample collection. We quantified the gene expressions associated with root meristem formation, auxin biosynthesis, perception, signaling, conjugation, and cytokinin signaling in shoots harvested from 2- to 36-month-old plants. After IBA treatment, 702 transcripts changed their expressions. Several were involved in hormone homeostasis and the signaling pathways that determine cell dedifferentiation, leading to root meristem formation. In part, the age-related decline in the rooting capacity is attributable to the increase in the ARR1 gene expression, which negatively affects auxin homeostasis. The analysis of the transcriptomic variation in the leaves and rooting zones provided profuse information: (1) To elucidate the auxin metabolism; (2) to understand the hormonal and signaling processes involved; (3) to collect data associated with their recalcitrance.

2.
Sci Rep ; 10(1): 6106, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32269241

RESUMO

Many plant species bear fruits that suggest adaptation to seed dispersal by extinct megafauna. Present-day seed dispersal of these megafaunal plants is carried out by rodents, which can act as predators or dispersers; whether this interaction is primarily positive or negative can depend on the context. Here, we parameterized a stochastic model using data from the field and experimental arenas to estimate the effect of rodents on the recruitment of Myrcianthes coquimbensis -an Atacama Desert shrub with megafaunal fruits- and examine whether environmental conditions can alter the sign and strength of these rodent-plant interactions. We show that the outcome of these interactions is context-dependent: in wet conditions seed removal by rodents negatively impacts the recruitment probability of M. coquimbensis; in contrast, in dry conditions, the interaction with rodents increases recruitment success. In all cases, the strength of the effect of rodents on the recruitment success was determined mainly by their role as dispersers, which could be positive or negative. This study demonstrates that by caching seeds, rodents can be effective dispersers of a megafaunal fruit plant, but that the sign and magnitude of their effect on recruitment changes as a function of the environmental context in which the interaction occurs.


Assuntos
Comportamento Alimentar , Myrtaceae/fisiologia , Roedores/fisiologia , Dispersão de Sementes , Animais , Ecossistema , Frutas/fisiologia , Tempo (Meteorologia)
5.
Arch. cardiol. Méx ; Arch. cardiol. Méx;88(4): 298-305, oct.-dic. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-1124151

RESUMO

Resumen Se trata de un estudio de revisión de datos publicados en literatura médica relacionada con el cribado usado para la detección temprana de cardiopatías congénitas complejas en recién nacidos aparentemente sanos en diversas ciudades del mundo, incluyendo los reportados en México, desde aquellos en los que se realiza el cribado por el conocimiento de la fisiopatologìa de datos indirectos de hipoxia, observación de cianosis diferencial y la consecuente diferencia en los valores de la pulsioximetría pre y posductal derivada de la dependencia ductal y/o de comunicación interauricular de diversas cardiopatías congénitas graves, hasta aquellos estudios de investigación realizados de forma masiva y reportados como multicéntricos, justificando la utilidad de la práctica para su implementación cotidiana y obligada de forma extensa a nivel internacional. Asimismo se citan tópicos legislativos en nuestro país como parte de los esfuerzos para establecer la obligatoriedad del cribado en toda la República Mexicana.


Abstract A review is presented of data published in medical literature related to the screening used for the early detection of complex congenital heart disease in apparently healthy newborns in several cities of the world, including those reported in Mexico. The screening wasperformed due to the knowledge of the pathophysiology of indirect hypoxia data, observation of differential cyanosis and the consequent difference in the values of pre- and post-ductal pulse oximetry derived from the ductal and/or atrial septal defect dependence of several severe congenital heart diseases. Multicentre research studies have also been carried out on a massive scale, thus justifying the usefulness of the practice for its daily implementation and at international level. Additionally, legislative topics are cited in our country as part of the efforts to establish the mandatory nature of the screening throughout the Mexican Republic.


Assuntos
Humanos , Recém-Nascido , Oximetria/métodos , Triagem Neonatal/métodos , Cardiopatias Congênitas/diagnóstico , Diagnóstico Precoce , Cardiopatias Congênitas/fisiopatologia , Hipóxia/diagnóstico , México
6.
Rev. biol. trop ; Rev. biol. trop;66(2): 593-604, abr.-jun. 2018. tab
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-977331

RESUMO

Resumen El origen geográfico de la semilla ejerce un control genético sobre los caracteres de comportamiento de las plantas por lo cual su selección es una herramienta útil para lograr la máxima adaptación de la especie al medio. En este sentido, la caracterización de materiales de diferentes procedencias brinda información para la elección de las fuentes de semilla utilizables en programas de mejora, así como en proyectos de forestación y/o repoblación. El presente trabajo tuvo como objetivo establecer el efecto de la procedencia sobre las variables morfológicas que constituyen parámetros de calidad en plantines de Prosopis alba provenientes de tres áreas geográficas. Se midieron variables morfológicas de las plantas hasta los 150 días posteriores a la siembra. El efecto de la procedencia resultó significativo para la mayoría de las variables medidas: altura de las plantas y diámetro a la altura del cuello (al menos durante los primeros 3 meses de viverización), volumen de raíz, peso foliar específico y área foliar específica. Así mismo algunos de los índices y cocientes morfológicos considerados como variables para determinar la calidad de plantas resultan afectados por el origen geográfico del material: relación longitud parte aérea/parte radical, coeficiente de esbeltez e índice de esbeltez. Los resultados permiten afirmar que en P. alba la procedencia influye sobre la morfología de las plantas y determina la existencia de dos grupos diferentes: por un lado, las procedencias santiagueña y chaqueña y, por otro, la procedencia Salta Norte.


Abstract Seed provenance has a genetic control over the behavioral characteristics of plants, whereby selection is an useful tool to achieve the maximum adaptation of the species to the environment. In this sense, different provenance materials characterization provides information for choosing seed sources used in breeding programs, as well as afforestation and/or reforestation projects. The aim of this work was established provenance´s effect on morphological variables that constitute quality parameters in Prosopis alba seedlings from three geographic areas. Morphological plants´ variables were measured up to 150 days after planting. Provenance effect was significant for most of measured variables: plant´s height, neck diameter (at least during the first 3 months of nursery), root volume, specific leaf weight and specific leaf area. Likewise, some of the morphological indices and quotients considered variables to determine plants´ quality are affected by material´s geographical origin: shoot length/ root length proportion, slenderness coefficient and index. Results allow affirming P. alba´s provenance influences plants´ morphology determining the existence of two different groups: on one hand Santiago del Estero and Chaco provenances, and on the other, Salta Norte origin. Rev. Biol. Trop. 66(2): 593-604. Epub 2018 June 01.


Assuntos
Análise de Variância , Geomorfologia , Prosopis/anatomia & histologia , Fabaceae/anatomia & histologia
8.
Arch Cardiol Mex ; 88(4): 298-305, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-29548601

RESUMO

A review is presented of data published in medical literature related to the screening used for the early detection of complex congenital heart disease in apparently healthy newborns in several cities of the world, including those reported in Mexico. The screening was performed due to the knowledge of the pathophysiology of indirect hypoxia data, observation of differential cyanosis and the consequent difference in the values of pre- and post-ductal pulse oximetry derived from the ductal and/or atrial septal defect dependence of several severe congenital heart diseases. Multicentre research studies have also been carried out on a massive scale, thus justifying the usefulness of the practice for its daily implementation and at international level. Additionally, legislative topics are cited in our country as part of the efforts to establish the mandatory nature of the screening throughout the Mexican Republic.


Assuntos
Cardiopatias Congênitas/diagnóstico , Triagem Neonatal/métodos , Oximetria/métodos , Diagnóstico Precoce , Cardiopatias Congênitas/fisiopatologia , Humanos , Hipóxia/diagnóstico , Recém-Nascido , México
9.
PLoS One ; 11(11): e0166824, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27861550

RESUMO

Scatter-hoarding rodents can act as both predators and dispersers for many large-seeded plants because they cache seeds for future use, but occasionally forget them in sites with high survival and establishment probabilities. The most important fruit or seed trait influencing rodent foraging behavior is seed size; rodents prefer large seeds because they have higher nutritional content, but this preference can be counterbalanced by the higher costs of handling larger seeds. We designed a cafeteria experiment to assess whether fruit and seed size of Myrcianthes coquimbensis, an endangered desert shrub, influence the decision-making process during foraging by three species of scatter-hoarding rodents differing in body size: Abrothrix olivaceus, Phyllotis darwini and Octodon degus. We found that the size of fruits and seeds influenced foraging behavior in the three rodent species; the probability of a fruit being harvested and hoarded was higher for larger fruits than for smaller ones. Patterns of fruit size preference were not affected by rodent size; all species were able to hoard fruits within the entire range of sizes offered. Finally, fruit and seed size had no effect on the probability of seed predation, rodents typically ate only the fleshy pulp of the fruits offered and discarded whole, intact seeds. In conclusion, our results reveal that larger M. coquimbensis fruits have higher probabilities of being harvested, and ultimately of its seeds being hoarded and dispersed by scatter-hoarding rodents. As this plant has no other dispersers, rodents play an important role in its recruitment dynamics.


Assuntos
Frutas , Comportamento Predatório , Roedores , Dispersão de Sementes , Sementes , Estreptófitas , Animais
10.
Cochabamba; s.n; abr. 2011. 124 p. graf.
Tese em Espanhol | LIBOCS, LILACS, LIBOE | ID: biblio-1296177

RESUMO

Las condiciones de vivienda y saneamiento básico son fundamentales para llevar una vida sana y de calidad; sin embargo, al no contar con los mismos o si éstos son utilizados de manera ineficiente, llega a ser dañino para la salud. El presente estudio relacionó estos factores de vivienda y saneamiento básico con la incidencia de dos enfermedades con más altas tasas de de morbi mortalidad en niños/as menores de 5 años, en el hospital de segundo nivel de Quillacollo, con un total de 98 menores de 5 años que asistieron a consulta externa por una de estas dos enfermedades.Un 73.6% de niños/as que tuvo diarrea y un 74.4% que tuvo tos, cuenta con servicios básicos adecuados como agua por cañería, recojo de basura a través de un carro basurero y alcantarillado, y un 26.4% que tuvo diarrea y un 25.6% que tuvo tos, cuentan con servicios alternativos como agua de pozo, disposición de basura a través de un contenedor y letrina sanitaria. Estos resultados llevaron a la elaboración de propuestas de educación para el mejoramiento de las condiciones de vivienda y saneamiento básico, tanto para el personal de salud y las autoridades del municipio, con el objetivo de sensibilizar a los mismos y lograr una mayor atención a la población, velando de esta manera por la salud, sobre todo la infantil


Assuntos
Criança , Bolívia , Diarreia Infantil/epidemiologia , Doença Ambiental/epidemiologia , Doença Ambiental/prevenção & controle , Doenças Respiratórias/epidemiologia
11.
Methods Mol Biol ; 710: 215-25, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21207272

RESUMO

Tropical Ilex species have recalcitrant seeds. This chapter describes protocols for long-term conservation of Ilex brasiliensis, I. brevicuspis, I. dumosa, I. microdonta, I. integerrima, I. paraguariensis, I. pseudoboxus, I. taubertiana, and I. theezans through cryopreservation of zygotic rudimentary embryos at the heart developmental stage. The embryos are aseptically removed from the seeds and precultured (7 days) in the dark at 27±2°C on solidified quarter-strength Murashige and Skoog medium with 3% sucrose and 0.1 mg/L zeatin. The embryos are then encapsulated in 3% calcium alginate beads and pretreated at 24-h intervals in liquid medium supplemented with progressively increasing sucrose concentrations (0.5, 0.75, and 1 M). The beads are dehydrated for 5 h with silica gel to 25% water content (fresh weight basis) and then placed in sterile 5-mL cryovials. Then the beads are either plunged rapidly in liquid nitrogen where they are kept for 1 h (rapid cooling), or cooled at 1°C/min to -30°C and then immersed in liquid nitrogen for 1 h (slow cooling). After cryopreservation, the beads are rewarmed by immersion of the cryovials for 1 min in a water bath at 30°C. Finally, the beads are transferred onto culture medium (1/4MS, 3% sucrose, and 0.1 mg/L zeatin, solidified with 0.8% agar) and incubated in a growth room at 27±2°C under a 14-h light (116 µmol/m2/s) and 10-h dark photoperiod. Maximum recovery percentages between 15 and 83% (depending on the species and the treatment) were obtained with the cryopreserved embryos.


Assuntos
Ilex/embriologia , Sementes , Criopreservação/métodos , Crioprotetores , Glicerol , Sacarose
12.
Biocell ; 32(1): 33-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18669321

RESUMO

Tropical Ilex species have recalcitrant seeds. This work describes experiments demonstrating the feasibility of long-term conservation of Ilex brasiliensis, I. brevicuspis, I. dumosa, I. intergerrima, I. paraguariensis, I. pseudoboxus, I. taubertiana, and I. theezans through cryopreservation of zygotic rudimentary embryos at the heart developmental stage. The embryos were aseptically removed from the seeds and precultured (7 days) in the dark, at 27 +/- 2 degrees C on solidified (0.8% agar) 1/4MS medium, [consisting of quarter-strength salts and vitamins of Murashige and Skoog (1962) medium] with 3% sucrose and 0.1 mg/l Zeatin. The embryos were then encapsulated in 3% calcium alginate beads and pretreated at 24 h intervals in liquid medium supplemented with progressively increasing sucrose concentrations (0.5, 0.75 and 1 M). Beads were dehydrated for 5 h with silicagel to 25% water content (fresh weight basis) and then placed in sterile 5 ml cryovials. Then the beads were either plunged rapidly in liquid nitrogen were they were kept for 1 h (rapid cooling) or cooled at 1 degrees C min(-1) to -30 degrees C. Then the beads were immersed in liquid nitrogen for 1 h (slow cooling). The beads were rewarmed by immersion of the cryovials for 1 min in a water bath thermostated at 30 degrees C. Finally, beads were transferred onto culture medium (1/4MS, 3% sucrose, 0.1 mg/l zeatin, solidified with 0.8% agar) and incubated in a growth room at 27 +/- 2 degrees C under a 14 h light (116 micromol. m(-2) x s(-1))/ 10 h dark photoperiod. Maximum recovery percentages between 15 and 83% (depending on de the species and the treatment) were obtained with the cryopreserved embryos.


Assuntos
Criopreservação/métodos , Ilex/embriologia , Sementes/fisiologia , Sobrevivência Celular , Germinação , Ilex/fisiologia , Sementes/efeitos dos fármacos , Técnicas de Cultura de Tecidos
13.
Med Oral Patol Oral Cir Bucal ; 10(5): 394-401, 2005.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-16264387

RESUMO

Multifocal epithelial hyperplasia (MEH) is also known as focal epithelial hyperplasia, Heck's disease or multifocal papillomavirus-induced epithelial hyperplasia. It is characterised by the presence of multiple lesions in the oral mucosa of children and it has been associated with the presence of the human papillomavirus. The aim of this study was to determine the clinico-pathological features of the cases diagnosed as MEH in the Service of Dermatology of the Hospital Manuel Gea González (SDHMGG). The files of the SDHMGG were reviewed and all cases diagnosed as MEH were retrieved. Nine MEH cases were found. Most of the patients were 20 year-old or younger (67%) and females were more commonly affected (78%). All patients presented multiple lesions and always, close relatives with similar lesions were found. Lesions were located most commonly in the buccal mucosa, lower lip and commissures. MEH is a soft tissue intraoral condition that needs treatment solely of the traumatised lesions or those with cosmetic problems. Remaining lesions will disappear with the age of the patients. It is suggested that this entity should be named multifocal epithelial hyperplasia since this name describes better the clinico-pathological and microscopic features of the disease.


Assuntos
Hiperplasia Epitelial Focal/patologia , Adolescente , Adulto , Fatores Etários , Criança , Crioterapia , Saúde da Família , Feminino , Hiperplasia Epitelial Focal/terapia , Hiperplasia Epitelial Focal/virologia , Humanos , Masculino , Nitrogênio/uso terapêutico , Papillomaviridae/patogenicidade , Pobreza , Estudos Retrospectivos , Razão de Masculinidade
14.
Biocell ; Biocell;24(1): 53-63, Apr. 2000.
Artigo em Inglês | BINACIS | ID: bin-6405

RESUMO

In vitro regeneration of complete plants from nodal single bud segments of "yerba mate" (Ilex paraguariensis St. Hil.) was studied under defined nutritional and environmental conditions. Nodal segments harvested from actively growing shoots of conventionally raised plants were cultured on nutrient medium with the mineral salts and vitamins of Murashige and Skoog medium at 1/4 strength, supplemented with various concentrations of sucrose and 6-benzyladenine (BAP). Shoot regeneration from explants of both young (2 years old) and adult (20 years old) mother plants were readily achieved in the medium supplemented with 0.04-0.09 M sucrose with or without BAP. As many as 60-65 of the nodal segments cultured formed shoots. Rooting of regenerated shoots was observed in 50 of the explants harvested from young plants, whereas 25 of the explants rooted when the nodal explants were harvested from adult plants. The best rooting induction was achieved on 1/4 strength MS medium with vermiculite as the substrate and supplemented with 1-1.5 IBA (indolebutyric acid) and 1-2 PPZ (3-methyl-1-phenyl-2 pyrazolin-5-one). Plantlets were successfully transferred to soil.(AU)


Assuntos
RESEARCH SUPPORT, NON-U.S. GOVT , Fenômenos Fisiológicos Vegetais , Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Brotos de Planta/fisiologia , Regeneração
15.
Biocell ; Biocell;24(1): 53-63, Apr. 2000.
Artigo em Inglês | LILACS | ID: lil-335913

RESUMO

In vitro regeneration of complete plants from nodal single bud segments of "yerba mate" (Ilex paraguariensis St. Hil.) was studied under defined nutritional and environmental conditions. Nodal segments harvested from actively growing shoots of conventionally raised plants were cultured on nutrient medium with the mineral salts and vitamins of Murashige and Skoog medium at 1/4 strength, supplemented with various concentrations of sucrose and 6-benzyladenine (BAP). Shoot regeneration from explants of both young (2 years old) and adult (20 years old) mother plants were readily achieved in the medium supplemented with 0.04-0.09 M sucrose with or without BAP. As many as 60-65 of the nodal segments cultured formed shoots. Rooting of regenerated shoots was observed in 50 of the explants harvested from young plants, whereas 25 of the explants rooted when the nodal explants were harvested from adult plants. The best rooting induction was achieved on 1/4 strength MS medium with vermiculite as the substrate and supplemented with 1-1.5 IBA (indolebutyric acid) and 1-2 PPZ (3-methyl-1-phenyl-2 pyrazolin-5-one). Plantlets were successfully transferred to soil.


Assuntos
Fenômenos Fisiológicos Vegetais , Plantas , Brotos de Planta , Raízes de Plantas/fisiologia , Regeneração
16.
Artigo em Espanhol | BINACIS | ID: bin-7395

RESUMO

It has been observed that a high percentage of students present problems with the spinal column; this is due to the lack of prevention in the activities of daily life and in hospitals practice. Added to this, is the presence of a large percentage of alterations of the feet. This coincides with our hypothesis of work, and brings us to suggest the correct positions in the principal postures.(Au)


Assuntos
Humanos , Masculino , Feminino , Adulto , Doenças da Coluna Vertebral/epidemiologia , Argentina/epidemiologia , Prevalência , Distribuição por Sexo , Doenças da Coluna Vertebral/prevenção & controle
17.
Rev. Fac. Cienc. Méd. (Córdoba) ; Rev. Fac. Cienc. Méd. (Córdoba);50(1): 35-37, 1992.
Artigo em Espanhol | LILACS | ID: lil-320217

RESUMO

It has been observed that a high percentage of students present problems with the spinal column; this is due to the lack of prevention in the activities of daily life and in hospitals' practice. Added to this, is the presence of a large percentage of alterations of the feet. This coincides with our hypothesis of work, and brings us to suggest the correct positions in the principal postures.


Assuntos
Humanos , Masculino , Feminino , Adulto , Doenças da Coluna Vertebral/epidemiologia , Argentina , Doenças da Coluna Vertebral/prevenção & controle , Prevalência , Distribuição por Sexo
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