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1.
J Sci Food Agric ; 104(10): 6311-6321, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38482895

RESUMO

BACKGROUND: As a result of the ineffectiveness of existing control methods against Verticillium dahliae, the causal agent of verticillium wilt of olive (Olea europaea; VWO), it is necessary to search for sustainable and environmentally friendly alternatives, such as bioprotection by products based on plant extracts and other naturally synthesized compounds. Therefore, present study aimed to evaluate the effects of seven natural-based commercial products on the inhibition of mycelial growth, the germination of V. dahliae conidia and microsclerotia, and disease progression in olive plants (cv. Picual). Aluminium lignosulfonate and a copper phosphonate salt (copper phosphite) were included for comparative purposes. RESULTS: The seaweed and willow extracts and copper phosphite inhibited V. dahliae mycelial growth by more than 50% at the high doses tested. Most of the products inhibited conidial germination by up to 90% compared to the control at the high doses tested. However, none of the products showed efficacy above 50% in inhibiting microsclerotia germination. The willow extract was the most effective at reducing disease severity and progression in olive plants, with no significant differences compared to the non-inoculated negative control. CONCLUSION: The results of the present study suggest that the use of natural-based products (i.e. seaweed and willow extracts) is a potential sustainable alternative in an integrated VWO control strategy. © 2024 Society of Chemical Industry.


Assuntos
Olea , Doenças das Plantas , Olea/microbiologia , Olea/química , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Alga Marinha/microbiologia , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Verticillium
2.
Plant Cell Environ ; 44(5): 1346-1360, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33347627

RESUMO

Capparis odoratissima is a tree species native to semi-arid environments of South America where low soil water availability coexists with frequent night-time fog. A previous study showed that water applied to leaf surfaces enhanced leaf hydration, photosynthesis and growth, but the mechanisms of foliar water uptake are unknown. Here, we combine detailed anatomical evaluations with water and dye uptake experiments in the laboratory, and use immunolocalization of pectin and arabinogalactan protein epitopes to characterize water uptake pathways in leaves. Abaxially, the leaves of C. odoratissima are covered with peltate hairs, while the adaxial surfaces are glabrous. Both surfaces are able to absorb condensed water, but the abaxial surface has higher rates of water uptake. Thousands of idioblasts per cm2 , a higher density than stomata, connect the adaxial leaf surface and the abaxial peltate hairs, both of which contain hygroscopic substances such as arabinogalactan proteins and pectins. The highly specialized anatomy of the leaves of C odoratissima fulfils the dual function of minimizing water loss when stomata are closed, while maintaining the ability to absorb liquid water. Cell-wall related hygroscopic compounds in the peltate hairs and idioblasts create a network of microchannels that maintain leaf hydration and promote water uptake.


Assuntos
Absorção Fisiológica , Capparis/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Água/metabolismo , Corantes Fluorescentes/metabolismo , Modelos Biológicos , Mucoproteínas/metabolismo , Pectinas/metabolismo , Proteínas de Plantas/metabolismo
4.
J Fungi (Basel) ; 10(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38392810

RESUMO

Verticillium wilt of olive (VWO) caused by Verticillium dahliae is considered a major olive (Olea europaea) disease in Mediterranean-type climate regions. The lack of effective chemical products against VWO makes it necessary to search for alternatives such as biological control. The main goal of this study was to evaluate the effect of six Streptomyces spp. strains as biological control agents (BCAs) against VWO. All of them were molecularly characterized by sequencing 16S or 23S rRNA genes and via phylogenetic analysis. Their effect was evaluated in vitro on the mycelial growth of V. dahliae (isolates V004 and V323) and on microsclerotia (MS) viability using naturally infested soils. Bioassays in olive plants inoculated with V. dahliae were also conducted to evaluate their effect against disease progress. In all the experiments, the reference BCAs Fusarium oxysporum FO12 and Aureobasidium pullulans AP08 were included for comparative purposes. The six strains were identified as Streptomyces spp., and they were considered as potential new species. All the BCAs, including Streptomyces strains, showed a significant effect on mycelial growth inhibition for both V. dahliae isolates compared to the positive control, with FO12 being the most effective, followed by AP08, while the Streptomyces spp. strains showed an intermediate effect. All the BCAs tested also showed a significant effect on the inhibition of germination of V. dahliae MS compared to the untreated control, with FO12 being the most effective treatment. Irrigation treatments with Streptomyces strain CBQ-EBa-21 or FO12 were significantly more effective in reducing disease severity and disease progress in olive plants inoculated with V. dahliae compared to the remaining treatments. This study represents the first approach to elucidating the potential effect of Streptomyces strains against VWO.

5.
Plants (Basel) ; 11(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35270115

RESUMO

Macrophomina phaseolina and Rhizoctonia solani are considered two major soil-borne pathogens of Phaseolus vulgaris in Cuba. Their management is difficult, not only due to their intrinsic biology as soil-borne pathogens, but also because the lack of active ingredients available against these pathogens. Actinobacteria, a heterogeneous bacterial group traditionally known as actinomycetes have been reported as promising biological control agents (BCAs) in crop protection. Thus, the main objective of this study was to evaluate the effectiveness of 60 actinobacterial strains as BCAs against M. phaseolina and R. solani in vitro by dual culture assays. The most effective strains were characterized according to their cellulolytic, chitinolytic and proteolytic extracellular enzymatic activity, as well as by their morphological and biochemical characters in vitro. Forty and 25 out of the 60 actinobacteria strains inhibited the mycelial growth of M. phaseolina and R. solani, respectively, and 18 of them showed a common effect against both pathogens. Significant differences were observed on their enzymatic and biochemical activity. The morphological and biochemical characters allow us to identify all our strains as species belonging to the genus Streptomyces. Streptomyces strains CBQ-EA-2 and CBQ-B-8 showed the highest effectiveness in vitro. Finally, the effect of seed treatments by both strains was also evaluated against M. phaseolina and R. solani infections in P. vulgaris cv. Quivicán seedlings. Treatments combining the two Streptomyces strains (CBQ-EA-2 + CBQ-B-8) were able to reduce significantly the disease severity for both pathogen infections in comparison with the non-treated and inoculated control. Moreover, they showed similar effect than that observed for Trichoderma harzianum A-34 and with Celest® Top 312 FS (Syngenta®; Basilea, Switzerland) treatments, which were included for comparative purposes.

6.
Ann N Y Acad Sci ; 1483(1): 67-79, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31868250

RESUMO

Scant empirical attention has been devoted to understanding endings in youth mentoring relationships, despite the frequency with which they occur. This study examined data from a mixed-methods study of mentoring relationship endings in which youth mentees, the youth's parents or guardians, mentors, and program staff were surveyed about the closure process, and a subsample of program staff, mentors, and parents or guardians also participated in in-depth qualitative interviews. Findings from a descriptive analysis detailing the perceptions of multiple stakeholders in the closure process as reported in surveys are presented along with case studies derived from a case-based analysis of in-depth qualitative interview data. Most relationship endings were initiated by the mentors, and although some matches engaged in an intentional and direct closure process, more often the endings were unclear or even confusing to program participants. Implications for practice are discussed, including recommendations for more training and greater involvement of program staff in the closure process, as are implications for future research.


Assuntos
Relações Interpessoais , Tutoria , Mentores , Adolescente , Adulto , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde
7.
Front Plant Sci ; 10: 268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930915

RESUMO

The formation and functioning of arbuscular mycorrhizal (AM) symbiosis are complex and tightly regulated processes. Transcriptional regulation mechanisms have been reported to mediate gene expression changes closely associated with arbuscule formation, where nutrients move between the plant and fungus. Numerous genes encoding transcription factors (TFs), with those belonging to the GRAS family being of particular importance, are induced upon mycorrhization. In this study, a screening for candidate transcription factor genes differentially regulated in AM tomato roots showed that more than 30% of known GRAS tomato genes are upregulated upon mycorrhization. Some AM-upregulated GRAS genes were identified as encoding for transcription factors which are putative orthologs of previously identified regulators of mycorrhization in other plant species. The symbiotic role played by other newly identified AM-upregulated GRAS genes remains unknown. Preliminary results on the involvement of tomato SlGRAS18, SlGRAS38, and SlGRAS43 from the SCL3, SCL32, and SCR clades, respectively, in mycorrhization are presented. All three showed high transcript levels in the late stages of mycorrhization, and the analysis of promoter activity demonstrated that SlGRAS18 and SlGRAS43 are significantly induced in cells containing arbuscules. When SlGRAS18 and SlGRAS38 genes were silenced using RNA interference in hairy root composite tomato plants, a delay in mycorrhizal infection was observed, while an increase in mycorrhizal colonization was observed in SlGRAS43 RNAi roots. The possible mode of action of these TFs during mycorrhization is discussed, with a particular emphasis on the potential involvement of the SHR/SCR/SCL3 module of GRAS TFs in the regulation of gibberellin signaling during mycorrhization, which is analogous to other plant developmental processes.

8.
J Bodyw Mov Ther ; 17(1): 125-36, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23294694

RESUMO

OBJECTIVE: The purposes of this study were to systematically review and apply regression analysis to randomised controlled trials [RCTs] that evaluated the effectiveness of Pilates exercise in improving persistent, non-specific low back pain and functional disability. METHODS: Electronic databases were searched from January 1950 to March 2011. Articles were eligible for inclusion if they were RCTs comparing Pilates exercise with a placebo treatment [PT], minimal intervention [MI] or another physiotherapeutic treatment [APT]. RESULTS: Nine trials were included. Pilates was moderately superior to APT (pooled Effect Size [ES] weighted = -0.55, 95% confidence interval [CI] = -0.08 to -1.03) in reducing disability but not for pain relief. Pilates provided moderate to superior pain relief compared to MI (pooled ES weighted = -0.44, 95% CI = -0.09 to -0.80) and a similar decrease in disability. The statistical model used did not detect any predictor variable. CONCLUSIONS: Due to the presence of co-interventions and the low methodological quality of some studies, these conclusions should be interpreted with caution.


Assuntos
Avaliação da Deficiência , Técnicas de Exercício e de Movimento/métodos , Dor Lombar/diagnóstico , Dor Lombar/reabilitação , Adolescente , Adulto , Fatores Etários , Idoso , Doença Crônica , Intervalos de Confiança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Regressão , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Resultado do Tratamento , Adulto Jovem
9.
J Evid Based Soc Work ; 9(3): 260-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22694132

RESUMO

The purpose of the authors in this study was to determine if the proportionality of peers who believe other youth are having oral sex or vaginal/anal intercourse influence the youth's intention to also have oral sex or vaginal/anal intercourse in the next three months. The results supported the hypothesis that the proportionality of perceiving one's peers as sexually active was correlated with one's intent to have oral sex in the next three months (r = .34 and .39, p < .01) and one's intent to have vaginal or anal sex within the next three months (r = .51 and r = .65, p < .01). Approximately 50% of youth who intent to have oral sex are also likely to have vaginal/anal sex. The results were not moderated by age, gender, or Hispanic/White status, but were moderated by being in a special/committed relationship.


Assuntos
Intenção , Grupo Associado , Percepção , Comportamento Sexual/psicologia , Sexualidade/psicologia , Adolescente , Comportamento do Adolescente/psicologia , Fatores Etários , Feminino , Humanos , Masculino
10.
J Bodyw Mov Ther ; 16(1): 109-14, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22196436

RESUMO

OBJECTIVE: The purpose of this systematic review was to determine how Pilates exercises have impacted body composition (BC) on selected populations. METHODS: A comprehensive literature search was performed using the keywords 'Pilates, body composition, systematic review, literature review, overweight, obesity, healthy weight, underweight' and their combination. RESULTS: Seven studies met the inclusion criteria and after further quality analyses it was determined that there is currently poor empirical quantitative evidence indicating a positive effect of Pilates exercises on BC. Several methodological flaws were observed in the studies analyzed, including few full-text published studies looking into the effects of Pilates exercises on BC, a lack of true experimental research designs, limited standardization in measurement techniques, insufficient or no control of the nutritional status, and inconsistent instructor qualifications. CONCLUSION: Well-designed research is needed to determine how Pilates exercises impact BC on selected populations.


Assuntos
Composição Corporal/fisiologia , Índice de Massa Corporal , Técnicas de Exercício e de Movimento/métodos , Obesidade/fisiopatologia , Obesidade/terapia , Humanos
11.
Rev. chil. cir ; 65(2): 166-171, abr. 2013. ilus
Artigo em Espanhol | LILACS | ID: lil-671269

RESUMO

Introduction: Tumors that are pathologically and immunohistochemically similar to gastrointestinal stromal tumors (GIST), but coming from soft tissues of the mesentery or retroperitoneum are called extra gastrointestinal stromal tumors (E-GISTs) and are more aggressive than GISTs. Clinical case: We report a 46 years old woman operated for a uterine sarcoma with a liver metastasis of the tumor, subsequently subjected to radiotherapy. A new CAT scan showed a 21 x 12 cm tumor. Radiotherapy was discontinued and the patient refused chemotherapy. Four years later, the patient consulted in the emergency room for a partial bowel obstruction. A new CAT scan showed a tumor that occupied the abdominal and pelvic cavity. The patient was operated, finding a highly vascularized and multisystem tumor that was fused together with the omentum, which was excised. The pathological diagnosis of the surgical piece was a high risk GIST.


Introducción: Los tumores del estroma gastrointestinal (GIST) fueron clasificados inicialmente dentro de otros grupos de tumores (leiomioma, leiomioblastoma, leiomiosarcoma), llamándolos leiomiomas bizarros o leiomiomas celulares debido a su apariencia histológica similar. Con el advenimiento de la microscopia electrónica se demostró que sólo algunos de estos tumores presentaban evidencias ultraestructurales de diferenciación muscular lisa. Posteriormente, los avances en la biología molecular y la inmunohistoquímica han permitido diferenciarlos de otras neoplasias digestivas e identificarlos como una patología clínica e histopatológica propia. Los tumores que histopatológicamente e inmunohistoquímicamente son similares a los GIST, pero proceden de los tejidos blandos del mesenterio o el retroperitoneo sin presentar conexión, ni siquiera tenue, con la pared ni con la superficie serosa de las vísceras, son denominanados tumores del estroma extragastrointestinal (E-GIST) y han mostrado tener un comportamiento más agresivo que los GIST originados a nivel gástrico y similar a los intestinales. Reporte del caso: Paciente de 47 años quien desarrolló durante 8 años un tumor abdominal, que resultó ser un tumor del estroma gastrointestinal de omento, sometida a tratamiento quirúrgico. En 18 meses no ha presentado recidiva tumoral.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias Peritoneais/cirurgia , Neoplasias Peritoneais/diagnóstico , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/diagnóstico , Células Intersticiais de Cajal , Neoplasias Peritoneais/patologia , Omento , Proteínas Proto-Oncogênicas c-kit , Tumores do Estroma Gastrointestinal/patologia
12.
Rev. peru. epidemiol. (Online) ; 16(2): 1-4, mayo.-ago 2012. tab, graf
Artigo em Espanhol | LILACS, LIPECS | ID: lil-706108

RESUMO

Objetivo: Determinar los factores de riesgo asociados al desarrollo de la retinopatía de la prematuridad (ROP) en neonatos prematuros. Métodos: Estudio caso control. Se evaluó factores neonatales en 31 neonatos con diagnóstico de ROP y 62 controles. Se estudiaron los neonatos con edad gestacional <37 semanas entre enero 2010 a diciembre 2011. Resultados: La media de peso al nacer fue 1647 gramos y la media de edad gestacional fue 33.99 semanas. La incidencia de ROP en neonatos con edad gestacional menor o igual a 32 semanas es 11.8% y en neonatos con peso al nacer < 1500 gr es 18.3%. Con el an lisis multivariado de regresión logística los factores significativos (p < 0.05) asociados a ROP fueron edad gestacional (OR= 6.27), peso al nacer (OR= 5.06), neumonía (OR= 6.42), asfixia neonatal (OR= 4.75), enfermedad de membrana hialina (OR= 8.74), transfusión sanguínea (OR = 18.49) y ventilación mecánica (OR = 13.63). Conclusiones: Bajo peso al nacer, menor edad gestacional, transfusión sanguínea, ventilación mecánica, neumonía, asfixia neonatal y membrana hialina son los principales factores de riesgo para el desarrollo de ROP.


Objective: To determine risk factors associated to retinopathy of prematurity (ROP) among premature infants. Methods: Case control study. 31 new born infants with ROP and 62 control infants were evaluated neonatal factors. We studied infants with gestational age < 37 weeks from January 2010 to December 2011. Results: Mean birth weight was 1647 gr. and mean gestational age was 33.8 weeks. The incidence of ROP was 11.8 % in infants with gestational age or less 32 weeks and 18.3% for infants with birth weight < 1500 g. In multivariate logistic regression analysis the significant factors (p < 0.05) associated to ROP were gestational age (OR = 6.27), birth weight (OR = 5.06), pneumonia (OR = 6.42), neonatal asphyxia (OR = 4.75), neonatal hyaline membrane (OR = 8.74), blood transfusion (OR = 18.49) and mechanical ventilation (OR = 13.63). Conclusions: Low birth weight, low gestational age, blood transfusion, mechanical ventilation and pneumonia, neonatal asphyxia and neonatal hyaline membrane are the main risk factors for the development of ROP.


Assuntos
Feminino , Idade Gestacional , Fatores de Risco , Recém-Nascido , Retinopatia da Prematuridade
13.
Plant Cell Environ ; 29(2): 247-56, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17080640

RESUMO

The specialized physiology of leafless, stem-succulent cacti is relatively well understood. This is not true, however, for Pereskia (Cactaceae), the 17 species of leafy trees and shrubs that represent the earliest diverging lineages of the cacti. Here we report on the water relations and photosynthesis of Pereskia guamacho, a small tree of the semiarid scrubland of Venezuela's Caribbean coast. Sapwood-specific xylem conductivity (Ksp) is low when compared to other vessel-bearing trees of tropical dry systems, but leaf-specific xylem conductivity is relatively high due to the high Huber value afforded by P. guamacho's short shoot architecture. P. guamacho xylem is not particularly vulnerable to drought-induced cavitation, especially considering the high leaf water potentials maintained year round. This is confirmed by the lack of significant variation exhibited in Ksp between wet and dry seasons. In the rainy season, P. guamacho exhibited C3-like patterns of stomatal conductance, but during a prolonged drought we documented nocturnal stomatal opening with a concomitant accumulation of titratable acid in leaves. This suggests that P. guamacho can perform drought-induced crassulacean acid metabolism (CAM photosynthesis), although delta 13C values imply that most carbon is assimilated via the C3 pathway. P. guamacho leaves display very low stomatal densities, and maximum stomatal conductance is low whether stomata open during the day or night. We conclude that leaf performance is not limited by stem hydraulic capacity in this species, and that water use is conservative and tightly regulated at the leaf level.


Assuntos
Cactaceae/fisiologia , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Água/fisiologia , Evolução Biológica , Carbono/metabolismo , Ecologia , Caules de Planta/fisiologia , Venezuela
14.
Clin Diagn Lab Immunol ; 9(1): 109-14, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11777839

RESUMO

The correlate of protection for serogroup B meningococci is not currently known, but for serogroup C it is believed to be the serum bactericidal assay (SBA). The current SBAs are labor intensive and the variations in protocols among different laboratories make interpretation of results difficult. A colorimetric SBA (cSBA), based on the ability of Neisseria meningitidis serogroup B to consume glucose, leading to acid production, was standardized by using group B strain Cu385-83 as the target. The cSBA results were compared to those obtained for a traditional colony-counting microassay (mSBA). Glucose and bromocresol purple pH indicator were added to the medium in order to estimate growth of cSBA target cell survivors through color change. Different variants of the assay parameters were optimized: growth of target cells (Mueller Hinton agar plates), target cell number (100 CFU/per well), and human complement source used at a final concentration of 25%. After the optimization, three other group B strains (H44/76, 490/91, and 511/91) were used as targets for the cSBA. The selection of the assay parameters and the standardization of cSBA were done with 13 sera from vaccinated volunteers. The titers were determined as the higher serum dilution that totally inhibited the bacterial growth marked by the color invariability of the pH indicator. This was detected visually as well as spectrophotometrically and was closely related to a significant difference in the growth of target cell survivors determined using Student's t test. Intralaboratory reproducibility was +/-1 dilution. The correlation between bactericidal median titers and specific immunoglobulin G serum concentration by enzyme immunoassay was high (r = 0.910, P < 0.01). The bactericidal titers generated by the cSBA and the mSBA were nearly identical, and there was a high correlation between the two assays (r = 0.974, P < 0.01). The standardized cSBA allows easy, fast, and efficient evaluation of samples.


Assuntos
Atividade Bactericida do Sangue , Neisseria meningitidis/imunologia , Adolescente , Adulto , Colorimetria , Proteínas do Sistema Complemento/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Neisseria meningitidis/classificação , Sensibilidade e Especificidade , Sorotipagem
15.
Rev. habanera cienc. méd ; 4(12)2005. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-412686

RESUMO

Se realizó un estudio en 25 pacientes de ambos sexos, mayores de 16 años que acudieron para su tratamiento al Servicio de Articulación Temporomandibular del Departamento de Prótesis de la Facultad de Estomatología de Ciudad de La Habana, con el objetivo de profundizar en el conocimiento de la relación entre la Sintomatología auditiva y los trastornos temporomandibulares. En 80(por ciwnto) de los pacientes estudiados, estaban presentes la Sintomatologia auditiva y el trastorno temporomandibular, 75(por ciento) de éstos presentaron como Sintomatología auditiva más frecuente la otalgia, siendo el dolor muscular y articular conjuntamente el más frecuente dentro del trastorno temporomandibular. También hubo predominio en la disminución de la dimensión vertical oclusiva en los pacientes estudiados


Assuntos
Humanos , Masculino , Adulto , Feminino , Dor de Orelha , Perda Auditiva , Transtornos da Articulação Temporomandibular , Síndrome da Disfunção da Articulação Temporomandibular , Dimensão Vertical
16.
Interciencia ; 26(10): 472-478, oct. 2001. mapas, tab, graf
Artigo em Espanhol | LILACS | ID: lil-341038

RESUMO

Las condiciones edáficas y climáticas que caracterizan las zonas áridas y semiáridas tropicales las colocan entre los ecosistemas más frágiles del mundo y más susceptibles a la desertificación. Esas zonas están sujetas a fuertes presiones debido al incremento poblacional y a cambios climáticos globales. Una de las causas principales de su degradación es la aplicación de tenologías agrícolas desarrolladas para áreas con condiciones ecológicas totalmente distintas. Es necesario estudiar sistemáticamente estos ecosistemas en sus condiciones naturales y analizar los mecanismos que utilizan las especies nativas para su supervivencia, a fin de proponer sistemas de producción fundamentados en la información generada. Los modelos deberán validarse a través de experimentos, utilizando la ecología como una herramienta fundamental en el proceso de planificación de sistemas de producción amigables con el ambiente y que conlleven al desarrollo sostenible. En las zonas áridas del noroeste de Venezuela, los resultados de investigaciones ecofisiológicas de las plantas dominantes y de cultivos alternativos en condiciones naturales y experimentales demuestran que la fenología de las plantas está acoplada a las lluvias efímeras y no a la estacionalidad climática, y que existe una alta compatibilidad y aumento de la productividad de especies suculentas cuando se asocian con árboles nativos. A partir de estos estudios se proponen sistemas agroforestales con la inclusión de cultivos suculentos (Aloe vera, Agave cocui, entre otros) bajo el resguardo del estrato arbóreo, a fin de proporcionar soluciones viables a los problemas de producción y degradación de las tierras áridas tropicales


Assuntos
Zona Árida , Biologia , Conservação dos Recursos Naturais/métodos , Ecologia , Ciência , Venezuela
17.
Rev. cuba. enferm ; 11(3): 9-10, oct.-dic. 1995.
Artigo em Espanhol | LILACS-Express | LILACS, BDENF | ID: lil-628247

RESUMO

Se describe el método de obtención de la vacuna DPT, desarrollada por primera vez en Cuba, y se expresan los resultados de las pruebas químicas y biológicas realizadas a 7 lotes de vacuna final. Se comprueba la eficiencia de la técnica de inmunodifusión radial simple para la prueba de identidad, y se compara con la prueba de floculación para la determinación de las concentraciones de los toxoides diftéricos y tetánicos presentes en la vacuna.

18.
Rev. cuba. farm ; 30(1)ene.-abr. 1996.
Artigo em Espanhol | LILACS | ID: lil-628410

RESUMO

La determinación de lipoproteínas en suero constituye una valoración de interés para el pesquisaje de las hiperlipoproteinemias. Es muy importante contar con un método rápido, sencillo y con un reactivo confiable que asegure dicha valoración. Se presentan los resultados logrados en pruebas de terreno en la provincia Habana con el reactivo ß pre-ß lipoproteína producido en la Empresa de Productos Biológicos "Carlos J. Finlay" y se comparan con un juego de reactivos para la determinación de colesterol con el propósito de analizar su correlación; los resultados obtenidos son satisfactorios. El coeficiente de correlación fue de 0,9997.


Determination of serum lipoproteins is an interesting assessment for the investigation of hyperlipoproteinemia. It is very important to count on a fast and simple method, and with a reliable reagent, to secure such assessment. Here the authors present the results obtained in field tests in Havana province, with the tested ß pre-ß lipoprotein reagent, produced at the "Carlos J. Finlay" biological products enterprise, and these results are compared with a reagent kit for cholesterol determination, with the aim for analysing their correlation. The outcomes were satisfactory. The correlation rate was 0,9997.

19.
Rev. cuba. farm ; 30(1)ene.-abr. 1996.
Artigo em Espanhol | LILACS | ID: lil-628403

RESUMO

La producción de toxoide tetánico se realiza a partir de la toxina tetánica destoxificada y purificada por métodos químicos. Un buen rendimiento de la toxina tetánica reviste gran importancia, pues éste es fundamental para obtener el número de dosis necesarias a un bajo costo. Se presentan los resultados obtenidos en la producción de toxina tetánica a partir de hidrolizado de caseína de producción nacional, mediante la realización de pruebas químicas, microbiológicas e inmunológicas, y se comprueba que el rendimiento es superior al obtenido con el hidrolizado de caseína de importación (triptona T, Oxoid).


The production of the tetanus toxoid is developed from the chemically detoxified and purified tetanus toxin. A good yielding of the tetanus toxin has a great importances, since it is fundamental to obtain the amount of necessary doses at a low cost. Here the authors present the results of the production of the tetanus toxin from the nationally produced casein hydrolysate, through chemical, microbiological, and immunological tests, and it is confirmed that the yield is higher than the one obtained with the imported casein hydrolysate (triptone T, Oxoid).

20.
Rev. cuba. farm ; 30(1)ene.-abr. 1996.
Artigo em Espanhol | LILACS | ID: lil-628404

RESUMO

La evaluación de la inmunidad celular mediante la respuesta producida por los linfocitos T, que son estimulados por la presencia de un antígeno determinado, es de sumo interés para el tratamiento de diversas enfermedades infecciosas que se producen durante el transcurso de quemaduras, lesiones, traumatismos, etcétera, por lo que la obtención de antígenos purificados para su uso en pruebas cutáneas que se emplean para dicha evaluación es de gran importancia. En nuestro trabajo nos dimos a la tarea de desarrollar un método de purificación para la obtención de uno de estos antígenos, a partir de la Candida albicans. El método utilizado fue el descrito por Buckley et al., al cual se le realizaron modificaciones. Se encontró que la metodología era adecuada y reproducible, pues el antígeno obtenido tenía características similares al antígeno de referencia.


The assessment of cellular immunity by means of the response produced by T-lymphocytes stimulated by the presence of a determined antigen, is of great interest in the treatment of several infectious diseases during the course of burns, lesions, traumas, etc., and due to this it is very important to obtain purified antigens for their usage in the skin tests used in such assessment. The authors developed a purification method to obtain one of these antigens, from Candida albicans. They carried out modifications on the method described by Buckley et al., and found that the methodology was adequate and reproducible, since the antigen obtained had similar characteristics to those of the reference antigen.

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