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1.
Sci Rep ; 11(1): 11867, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-34088933

RESUMEN

We investigate the magnetic nanoparticles hyperthermia in a non-adiabatic and radiating process through the calorimetric method. Specifically, we propose a theoretical approach to magnetic hyperthermia from a thermodynamic point of view. To test the robustness of the approach, we perform hyperthermia experiments and analyse the thermal behavior of magnetite and magnesium ferrite magnetic nanoparticles dispersed in water submitted to an alternating magnetic field. From our findings, besides estimating the specific loss power value from a non-adiabatic and radiating process, thus enhancing the accuracy in the determination of this quantity, we provide physical meaning to a parameter found in literature that still remained not fully understood, the effective thermal conductance, and bring to light how it can be obtained from experiment. In addition, we show our approach brings a correction to the estimated experimental results for specific loss power and effective thermal conductance, thus demonstrating the importance of the heat loss rate due to the thermal radiation in magnetic hyperthermia.

2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;53(1): e8659, Jan. 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1055485

RESUMEN

Eosinophils are abundant in the reproductive tract, contributing to the remodeling and successful implantation of the embryo. However, the mechanisms by which eosinophils migrate into the uterus and their relationship to edema are still not entirely clear, since there are a variety of chemotactic factors that can cause migration of these cells. Therefore, to evaluate the role of CCR3 in eosinophil migration, ovariectomized C57BL/6 mice were treated with CCR3 antagonist SB 328437 and 17β-estradiol. The hypothesis that the CCR3 receptor plays an important role in eosinophil migration to the mouse uterus was confirmed, because we observed reduction in eosinophil peroxidase activity in these antagonist-treated uteruses. The antagonist also influenced uterine hypertrophy, inhibiting edema formation. Finally, histological analysis of the orcein-stained uteruses showed that the antagonist reduced eosinophil migration together with edema. These data showed that the CCR3 receptor is an important target for studies that seek to clarify the functions of these cells in uterine physiology.


Asunto(s)
Animales , Femenino , Conejos , Útero/citología , Movimiento Celular/efectos de los fármacos , Eosinófilos/efectos de los fármacos , Estradiol/administración & dosificación , Estrógenos/administración & dosificación , Receptores CCR3/antagonistas & inhibidores , Ovariectomía , Ratones Endogámicos C57BL
3.
Braz J Med Biol Res ; 53(1): e8659, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31859912

RESUMEN

Eosinophils are abundant in the reproductive tract, contributing to the remodeling and successful implantation of the embryo. However, the mechanisms by which eosinophils migrate into the uterus and their relationship to edema are still not entirely clear, since there are a variety of chemotactic factors that can cause migration of these cells. Therefore, to evaluate the role of CCR3 in eosinophil migration, ovariectomized C57BL/6 mice were treated with CCR3 antagonist SB 328437 and 17ß-estradiol. The hypothesis that the CCR3 receptor plays an important role in eosinophil migration to the mouse uterus was confirmed, because we observed reduction in eosinophil peroxidase activity in these antagonist-treated uteruses. The antagonist also influenced uterine hypertrophy, inhibiting edema formation. Finally, histological analysis of the orcein-stained uteruses showed that the antagonist reduced eosinophil migration together with edema. These data showed that the CCR3 receptor is an important target for studies that seek to clarify the functions of these cells in uterine physiology.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Eosinófilos/efectos de los fármacos , Estradiol/administración & dosificación , Estrógenos/administración & dosificación , Receptores CCR3/antagonistas & inhibidores , Útero/citología , Animales , Femenino , Ratones , Ratones Endogámicos C57BL , Ovariectomía
4.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1509041

RESUMEN

Introducción: Reducir la pobreza y lograr cobertura universal de salud con protección financiera para las personas de todas las edades son parte de los Objetivos de Desarrollo Sostenible. Objetivo: Determinar el gasto de bolsillo de salud (GBS) ante la enfermedad de personas de 60 y más años (≥ 60 años) y su incidencia económica en los hogares según su condición de pobreza en Paraguay. Material y Método: Se analizó la Encuesta Permanente de Hogares del 2014, considerando la definición oficial de pobreza y la referencia de enfermedad o accidente en un trimestre. Se calculó el promedio de GBS por hogar, la incidencia sobre el ingreso monetario trimestral (IM) y sobre los subsidios estatales por pensión alimentaria para adultos mayores (IPa). Resultados: De los 1.621.525 hogares del país 435.448 tenía al menos 1 persona ≥ 60 años, de los cuales 188.715 tenía al menos 1 de ellos enfermo o accidentado y 144.554 reportó GBS. Entre los hogares no pobres: 11,6% (IC 10,5 a 12,9) tuvo al menos 1 enfermo ≥ 60 años, de los cuales 75,8% (IC 71,2 a 79,8) tuvo GBS, siendo en promedio 547.931 Gs. (DE 58.251). Los medicamentos fueron 53,3% (IC 45,2 a 61,5) del total. La IM fue 5,7% (IC 4,6 a 6,9). Entre los hogares pobres: 11,6% (IC 9,6 a 14,0) tuvo al menos 1 enfermo ≥ 60 años, de los cuales 79,5% (IC 70,7 a 86,2) tuvo GBS, siendo en promedio 341.542 Gs. (DE 49.101). Los medicamentos fueron 71,3% (IC 61,9 a 80,7) del total. La IM fue 11,5% (IC 7,0 a 16,0), la IPa fue de 16,9% (IC 4,4 a 29,4). El GBS fue el equivalente a 19 días de alimentación en promedio (DE 3,71). Conclusión: Paraguay requiere de mayor protección financiera para adultos mayores mediante sinergias de las políticas de reducción de pobreza y de salud.


Introduction: Reducing poverty and achieving universal health coverage for people of all ages are part of the Sustainable Development Goal. Objective: determine the Out-of-pocket Health Expenditure (GBS) for people 60 and older (≥ 60 years) who are sick and its economic impact on households according to their poverty status in Paraguay. Material and Method: the 2014 Permanent Household Survey was analyzed, considering the official definition of poverty and the reference of illness or accident in a quarter. The average of GBS per household, the impact on quarterly monetary risk (IM) and on state subsidies for food pensions for the elderly (IPa). Results: Of 1,621,525 homes in the country 435,448 had at least 1 person 60 years, of which 188,715 had at least 1 of them ill or injured and 144,554 reported GBS. Among the non-poor households: 11.6% (IC 10.5 to 12.9) had at least 1 ill person ≥ 60 years, of which 75.8% (IC 71.2 to 79.8) had GBS, being on average 547,931 Gs. (DE 58,251). The medications were 53.3% (IC 45.2 to 61.5) from total. There was an IM of 5,7% (IC 4.6 to 6.9). Among the poor households: 11.6% (IC 9.6 to 14.0) had at least 1 ill person ≥ 60 years, of which 79.5% (IC 70.7 to 86,2) had GBS, being on average 341,542 Gs. (DE 40,101). The medications were 71.3 % (IC 61.9 to 80.7) from total. There was an IM of 11.5% (IC 7.0 to 16.0). There was an IPa of 16.9% (IC 4.4 to 29.4). The GBS was the equivalent to 19 days of feeding on average (DE 3.71). Conclusion: Paraguay requires more financial protection for older adults through synergies of poverty reduction and health policies.

5.
Lett Appl Microbiol ; 67(1): 54-63, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29603295

RESUMEN

Zymomonas mobilis has long attracted attention owing to its capacity to ferment hexose to ethanol. From a taxonomic viewpoint, Z. mobilis is a unique species of the genus Zymomonas, separated into three subspecies, Z. mobilis subsp. mobilis, Z. mobilis subsp. pomaceae and Z. mobilis subsp. francensis on the basis of physiological tests, which are often unreliable owing to the genetic proximity among these species. Currently, the use of molecular techniques is more appropriate for identification of these bacterial subspecies. In this study, the 32 strains of Z. mobilis present in the UFPEDA bacterial collection were characterized using molecular techniques, such as sequencing of the 16S rDNA gene and its theoretical restriction profile, classifying them as members of the subspecies, Z. mobilis subsp. mobilis. In addition, anaerobic cultivations were performed, which showed the biological diversity of the strains in terms of growth, sugar consumption and ethanol production. From these results, it was possible to identify the strain Z-2-80 as a promising bacterium for use in the fermentation process. SIGNIFICANCE AND IMPACT OF THE STUDY: Zymomonas mobilis is a bacterium of great relevance to biotechnology, owing to its capacity to ferment hexose to ethanol. On a molecular basis, 32 isolates were identified as Z. mobilis subsp. mobilis. However, intraspecific diversity was identified when these were grown under strictly anaerobic conditions. The results obtained from this study suggest a strain of Z. mobilis as an alternative for use in the fermentation process.


Asunto(s)
Reactores Biológicos/microbiología , ADN Bacteriano/genética , Etanol/metabolismo , Zymomonas/clasificación , Zymomonas/metabolismo , Anaerobiosis , Brasil , ADN Ribosómico/genética , Fermentación , Hexosas/metabolismo , ARN Ribosómico 16S/genética , Zymomonas/genética , Zymomonas/aislamiento & purificación
6.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;51(1): e6799, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-889013

RESUMEN

Arthritis is positively associated with the decline of sex hormones, especially estrogen. Tamoxifen (TMX) is a selective estrogen receptor modulator, possessing agonist or antagonistic activity in different tissues. Thus, the objective of this study was to investigate the effect of TMX on the zymosan-induced arthritis model. Female Swiss normal and ovariectomized (OVX) mice were divided into groups and treated for five days with TMX (0.3, 0.9 or 2.7 mg/kg) or 17-β-estradiol (E2, 50 µg/kg). On the fifth day, arthritis was induced and 4 h later, leukocyte migration into joint cavities was evaluated. The neutrophil migration in OVX animals, but not in normal mice, treated with TMX (all tested doses) was significantly decreased compared with mice that received the vehicle (P≤0.05). Similarly, this effect was also demonstrated in the E2-treated group. Therefore, the present study demonstrates that TMX presented agonist effects in inhibiting neutrophil migration and preventing arthritis progression in OVX mice.


Asunto(s)
Animales , Femenino , Conejos , Artritis Experimental/tratamiento farmacológico , Tamoxifeno/farmacología , Ovariectomía , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tamaño de los Órganos/efectos de los fármacos , Factores de Tiempo , Útero/efectos de los fármacos , Zimosan , Movimiento Celular/efectos de los fármacos , Resultado del Tratamiento , Ciclo Estral/efectos de los fármacos , Modelos Animales de Enfermedad , Antagonistas de Estrógenos/farmacología , Ensayos de Migración de Leucocitos , Neutrófilos/efectos de los fármacos
7.
Braz J Med Biol Res ; 51(1): e6799, 2017 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-29160416

RESUMEN

Arthritis is positively associated with the decline of sex hormones, especially estrogen. Tamoxifen (TMX) is a selective estrogen receptor modulator, possessing agonist or antagonistic activity in different tissues. Thus, the objective of this study was to investigate the effect of TMX on the zymosan-induced arthritis model. Female Swiss normal and ovariectomized (OVX) mice were divided into groups and treated for five days with TMX (0.3, 0.9 or 2.7 mg/kg) or 17-ß-estradiol (E2, 50 µg/kg). On the fifth day, arthritis was induced and 4 h later, leukocyte migration into joint cavities was evaluated. The neutrophil migration in OVX animals, but not in normal mice, treated with TMX (all tested doses) was significantly decreased compared with mice that received the vehicle (P≤0.05). Similarly, this effect was also demonstrated in the E2-treated group. Therefore, the present study demonstrates that TMX presented agonist effects in inhibiting neutrophil migration and preventing arthritis progression in OVX mice.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Ovariectomía , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tamoxifeno/farmacología , Animales , Ensayos de Migración de Leucocitos , Movimiento Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Antagonistas de Estrógenos/farmacología , Ciclo Estral/efectos de los fármacos , Femenino , Ratones , Neutrófilos/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del Tratamiento , Útero/efectos de los fármacos , Zimosan
8.
Braz. j. biol ; Braz. j. biol;77(1): 191-198, Jan-Mar. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-839154

RESUMEN

Abstract Successful animal rearing under laboratory conditions for commercial processes or laboratory experiments is a complex chain that includes several stressors (e.g., sampling and transport) and incurs, as a consequence, the reduction of natural animal conditions, economic losses and inconsistent and unreliable biological results. Since the invasion of the bivalve Limnoperna fortunei (Dunker, 1857) in South America, several studies have been performed to help control and manage this fouling pest in industrial plants that use raw water. Relatively little attention has been given to the laboratory rearing procedure of L. fortunei, its condition when exposed to a stressor or its acclimation into laboratory conditions. Considering this issue, the aims of this study are to (i) investigate L. fortunei physiological responses when submitted to the depuration process and subsequent air transport (without water/dry condition) at two temperatures, based on glycogen concentrations, and (ii) monitor the glycogen concentrations in different groups when maintained for 28 days under laboratory conditions. Based on the obtained results, depuration did not affect either of the groups when they were submitted to approximately eight hours of transport. The variation in glycogen concentration among the specimens that were obtained from the field under depurated and non-depurated conditions was significant only in the first week of laboratory growth for the non-depurated group and in the second week for the depurated group. In addition, the tested temperature did not affect either of the groups that were submitted to transport. The glycogen concentrations were similar to those of the specimens that were obtained from the field in third week, which suggests that the specimens acclimated to laboratory conditions during this period of time. Thus, the results indicate that the air transport and acclimation time can be successfully incorporated into experimental studies of L. fortunei. Finally, the tolerance of L. fortunei specimens to the stressor tested herein can help us understand the invasive capacity of this mussel during the establishment process.


Resumo A criação bem sucedida de animais em condições de laboratório para processos comerciais ou experimentais é uma cadeia complexa que inclui vários fatores de estresse (ex. coleta e transporte) que tem como consequência a redução das condições naturais do animal, prejuízos econômicos e resultados biológicos inconsistentes. Desde a invasão do bivalve Limnoperna fortunei (Dunker, 1857) na América do Sul, vários estudos têm sido realizados para ajudar no controle e gestão dessa praga em plantas industriais que utilizam água. Relativamente pouca atenção tem sido dada ao processo de criação de L. fortunei em laboratório, sua condição quando exposta ao estresse e sua aclimatação a condições de laboratório. Considerando estes aspectos, os objetivos deste estudo foram: (i) investigar as respostas fisiológicas de L. fortunei submetidos ao processo de depuração e subsequente transporte (sem água/condição seca) em duas temperaturas, analisando as diferentes concentrações de glicogênio e (ii) monitorar as concentrações de glicogênio nos diferentes grupos, quando mantidos por 28 dias em condições de laboratório. Com base nos resultados obtidos, a depuração não afetou nenhum grupo quando eles foram submetidos a oito horas de transporte. A variação da concentração de glicogênio entre os espécimes do campo quando depurados e não depurados, foi significativa apenas em relação à primeira semana em laboratório para o grupo não depurado e à segunda semana para o grupo depurado. Além disto, a temperatura testada não afetou os grupos submetidos ao transporte. As concentrações de glicogénio foram semelhantes as dos espécimes do campo a partir da terceira semana, o que sugere que os espécimes estão aclimatados às condições de laboratoriais neste período de tempo. Assim, os resultados indicam que o transporte ao ar e o tempo de aclimatação podem ser incorporados com sucesso aos estudos experimentais com L. fortunei. Finalmente, o conhecimento sobre a tolerância de L. fortunei ao estresse pode ajudar a entender a capacidade invasiva deste durante o processo de estabelecimento.


Asunto(s)
Animales , Adaptación Fisiológica/fisiología , Mytilidae/fisiología , América del Sur , Manejo de Especímenes , Temperatura , Agua , Análisis de Varianza , Mytilidae/química , Glucógeno/análisis , Aclimatación/fisiología
9.
Braz. J. Biol. ; 77(1): 191-198, jan.-mar. 2017. graf, tab
Artículo en Inglés | VETINDEX | ID: vti-734874

RESUMEN

Successful animal rearing under laboratory conditions for commercial processes or laboratory experiments is a complex chain that includes several stressors (e.g., sampling and transport) and incurs, as a consequence, the reduction of natural animal conditions, economic losses and inconsistent and unreliable biological results. Since the invasion of the bivalve Limnoperna fortunei (Dunker, 1857) in South America, several studies have been performed to help control and manage this fouling pest in industrial plants that use raw water. Relatively little attention has been given to the laboratory rearing procedure of L. fortunei, its condition when exposed to a stressor or its acclimation into laboratory conditions. Considering this issue, the aims of this study are to (i) investigate L. fortunei physiological responses when submitted to the depuration process and subsequent air transport (without water/dry condition) at two temperatures, based on glycogen concentrations, and (ii) monitor the glycogen concentrations in different groups when maintained for 28 days under laboratory conditions. Based on the obtained results, depuration did not affect either of the groups when they were submitted to approximately eight hours of transport. The variation in glycogen concentration among the specimens that were obtained from the field under depurated and non-depurated conditions was significant only in the first week of laboratory growth for the non-depurated group and in the second week for the depurated group. In addition, the tested temperature did not affect either of the groups that were submitted to transport. The glycogen concentrations were similar to those of the specimens that were obtained from the field in third week, which suggests that the specimens acclimated to laboratory conditions during this period of time. Thus, the results indicate that the air transport and acclimation time can be successfully incorporated into experimental studies of L. fortunei[...](AU)


A criação bem sucedida de animais em condições de laboratório para processos comerciais ou experimentais é uma cadeia complexa que inclui vários fatores de estresse (ex. coleta e transporte) que tem como consequência a redução das condições naturais do animal, prejuízos econômicos e resultados biológicos inconsistentes. Desde a invasão do bivalve Limnoperna fortunei (Dunker, 1857) na América do Sul, vários estudos têm sido realizados para ajudar no controle e gestão dessa praga em plantas industriais que utilizam água. Relativamente pouca atenção tem sido dada ao processo de criação de L. fortunei em laboratório, sua condição quando exposta ao estresse e sua aclimatação a condições de laboratório. Considerando estes aspectos, os objetivos deste estudo foram: (i) investigar as respostas fisiológicas de L. fortunei submetidos ao processo de depuração e subsequente transporte (sem água/condição seca) em duas temperaturas, analisando as diferentes concentrações de glicogênio e (ii) monitorar as concentrações de glicogênio nos diferentes grupos, quando mantidos por 28 dias em condições de laboratório. Com base nos resultados obtidos, a depuração não afetou nenhum grupo quando eles foram submetidos a oito horas de transporte. A variação da concentração de glicogênio entre os espécimes do campo quando depurados e não depurados, foi significativa apenas em relação à primeira semana em laboratório para o grupo não depurado e à segunda semana para o grupo depurado. Além disto, a temperatura testada não afetou os grupos submetidos ao transporte. As concentrações de glicogénio foram semelhantes as dos espécimes do campo a partir da terceira semana, o que sugere que os espécimes estão aclimatados às condições de laboratoriais neste período de tempo. Assim, os resultados indicam que o transporte ao ar e o tempo de aclimatação podem ser incorporados com sucesso aos estudos experimentais com L. fortunei[...](AU)


Asunto(s)
Animales , Mytilidae/fisiología , Glucógeno/análisis , Adaptación Fisiológica , Especies Introducidas
10.
Braz J Biol ; 77(1): 191-198, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27509217

RESUMEN

Successful animal rearing under laboratory conditions for commercial processes or laboratory experiments is a complex chain that includes several stressors (e.g., sampling and transport) and incurs, as a consequence, the reduction of natural animal conditions, economic losses and inconsistent and unreliable biological results. Since the invasion of the bivalve Limnoperna fortunei (Dunker, 1857) in South America, several studies have been performed to help control and manage this fouling pest in industrial plants that use raw water. Relatively little attention has been given to the laboratory rearing procedure of L. fortunei, its condition when exposed to a stressor or its acclimation into laboratory conditions. Considering this issue, the aims of this study are to (i) investigate L. fortunei physiological responses when submitted to the depuration process and subsequent air transport (without water/dry condition) at two temperatures, based on glycogen concentrations, and (ii) monitor the glycogen concentrations in different groups when maintained for 28 days under laboratory conditions. Based on the obtained results, depuration did not affect either of the groups when they were submitted to approximately eight hours of transport. The variation in glycogen concentration among the specimens that were obtained from the field under depurated and non-depurated conditions was significant only in the first week of laboratory growth for the non-depurated group and in the second week for the depurated group. In addition, the tested temperature did not affect either of the groups that were submitted to transport. The glycogen concentrations were similar to those of the specimens that were obtained from the field in third week, which suggests that the specimens acclimated to laboratory conditions during this period of time. Thus, the results indicate that the air transport and acclimation time can be successfully incorporated into experimental studies of L. fortunei. Finally, the tolerance of L. fortunei specimens to the stressor tested herein can help us understand the invasive capacity of this mussel during the establishment process.


Asunto(s)
Adaptación Fisiológica/fisiología , Mytilidae/fisiología , Aclimatación/fisiología , Análisis de Varianza , Animales , Glucógeno/análisis , Mytilidae/química , América del Sur , Manejo de Especímenes , Temperatura , Agua
11.
Phys Rev E ; 96(6-1): 062143, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29347279

RESUMEN

What are the necessary ingredients for log-periodicity to appear in the dynamics of a random walk model? Can they be subtle enough to be overlooked? Previous studies suggest that long-range damaged memory and negative feedback together are necessary conditions for the emergence of log-periodic oscillations. The role of negative feedback would then be crucial, forcing the system to change direction. In this paper we show that small-amplitude log-periodic oscillations can emerge when the system is driven by positive feedback. Due to their very small amplitude, these oscillations can easily be mistaken for numerical finite-size effects. The models we use consist of discrete-time random walks with strong memory correlations where the decision process is taken from memory profiles based either on a binomial distribution or on a delta distribution. Anomalous superdiffusive behavior and log-periodic modulations are shown to arise in the large time limit for convenient choices of the models parameters.

12.
Genet Mol Res ; 15(1): 15017488, 2016 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26985927

RESUMEN

Actinobacteria are known to produce various secondary metabolites having antibiotic effects. This study assessed the antimicrobial potential of actinobacteria isolated from the rhizosphere of Caesalpinia pyramidalis Tul. from the Caatinga biome. Sixty-eight actinobacteria isolates were evaluated for antimicrobial activity against different microorganisms by disk diffusion and submerged fermentation, using different culture media, followed by determination of minimum inhibitory concentration (MIC) and chemical prospecting of the crude extract. Of the isolates studied, 52.9% of those isolated at 37°C and 47.05% of those isolated at 45°C had activity against Bacillus subtilis, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Fusarium moniliforme, and Candida albicans. When compared with others actinobacteria, the isolate C1.129 stood out with better activity and was identified by 16S rDNA gene analysis as Streptomyces parvulus. The crude ethanol extract showed an MIC of 0.97 µg/mL for MRSA and B. subtilis, while the ethyl acetate extract showed MIC of 3.9 µg/mL for S. aureus and MRSA, showing the greatest potential among the metabolites produced. Chemical prospecting revealed the presence of mono/sesquiterpenes, proanthocyanidin, triterpenes, and steroids in both crude extracts. This study evaluates S. parvulus activity against multi-resistant microorganisms such as MRSA. Thus, it proves that low-fertility soil, as is found in the Caatinga, may contain important microorganisms for the development of new antimicrobial drugs.


Asunto(s)
Actinobacteria/metabolismo , Antibacterianos/farmacología , Antifúngicos/farmacología , Productos Biológicos/farmacología , Caesalpinia/microbiología , Rizosfera , Actinobacteria/genética , Actinobacteria/aislamiento & purificación , Antibacterianos/química , Antifúngicos/química , Bacillus subtilis/efectos de los fármacos , Productos Biológicos/química , Candida albicans/efectos de los fármacos , Fusarium/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Filogenia , Staphylococcus aureus/efectos de los fármacos
13.
Genet Mol Res ; 14(2): 5435-44, 2015 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-26125739

RESUMEN

The increased incidence of fungal infections and the development of drug resistance have led to the search for microorganisms capable of producing bioactive metabolites with antifungal activity. Among these microorganisms, Streptomyces spp are distinguished mainly owing to their potential to secrete bioactive molecules. The aim of this study was to evaluate the production of secondary metabolites by Streptomyces sp TUR-10 against 12 fungal clinical isolates (yeast and filamentous fungi). In the preliminary screening, Streptomyces sp TUR-10 showed activity against 75% of the clinical isolates, and was selected for fermentation. In this assay, we tested three different media (MPE, M1, and ISP-4) for 96 h at pH 7.0 and 30°C for the production of bioactive metabolites. Increased production of bioactive compounds was observed when using the MPE medium for 48 h, with good activity against Candida pelliculosa. The minimum inhibitory concentration showed significant antifungal activity values ranging from 15.6 to 250 µg/mL. The actinobacterium was characterized by 16S rRNA analysis and the pattern suggested that the isolate studied belonged to the species Streptomyces ansochromogenes. The biotechnological potential of this strain was also demonstrated by the detection of the nrps and pks genes. These results indicate the production of secondary metabolites of biotechnological interest by actinobacteria from the rhizosphere, suggesting great potential for further research.


Asunto(s)
Antifúngicos/farmacología , Hongos/efectos de los fármacos , Metabolismo Secundario/genética , Streptomyces/química , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Candida/efectos de los fármacos , Candida/patogenicidad , Hongos/patogenicidad , Humanos , Pruebas de Sensibilidad Microbiana , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptomyces/genética , Streptomyces/metabolismo
14.
Genet Mol Res ; 14(1): 805-14, 2015 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-25730020

RESUMEN

Zymomonas mobilis is a Gram-negative bacterium that has drawn attention in the bioethanol industry. Besides bioethanol, this bacterium also produces other biotechnological products such as levans, which show antitumor activity. Molecular studies involving Z. mobilis have advanced to the point that allows us to characterize interspecies genetic diversity and understand their metabolism, and these data are essential for better utilization of this species. In this study, the genetic diversity of 24 strains from the Microorganisms Collection of Departamento de Antibióticos (UFPEDA) from Universidade Federal de Pernambuco were characterized. The methods used were amplified ribosomal DNA restriction analysis and diversity analysis of the internally transcribed 16S-23S rDNA spacer region (ISR). These analyses revealed low genetic variability of the 16S rDNA gene. These data confirm that these isolates are, or are closely related to, Z. mobilis. Moreover, the analysis of the ISR confirmed the genetic variability of strains deposited in the UFPEDA collection of microorganisms and grouped these strains into ten ribotypes, which can be used in the future for breeding programs and for the preservation of biodiversity. Furthermore, this study characterized the genetic variability between the UFPEDA 205/ ZAP, UFPEDA 98/AG11, and ZAG strains, which were obtained by spheroplast fusion among them. The data also indicate that there is genetic variability among the UFPEDA 202/CP4 and UFPEDA 633/ ZM4 strains, demonstrating that these important Z. mobilis strains are distinct, as suggested in previous studies.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , ADN Ribosómico/genética , Variación Genética , Zymomonas/genética , Biocombustibles/microbiología , Etanol/metabolismo , Zymomonas/metabolismo
15.
J Helminthol ; 86(3): 348-52, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21838959

RESUMEN

The present study aimed to evaluate the ovicidal activity (type 3 effect) of VC1 and VC4 isolates of Pochonia chlamydosporia in a solid medium and the action of a crude extract of P. chlamydosporia against eggs of Ascaridia galli. To evaluate ovicidal activity in culture medium, 1000 A. galli eggs were plated on Petri dishes containing 2% water-agar with grown fungal isolates (VC1 or VC4) and without fungus (control group) and were examined at 1, 3 and 5 days post-inoculation (assay A). Then, to test the action of crude extracts of P. chlamydosporia (VC1 or VC4), 500 eggs of A. galli were plated on Petri dishes of 4.5 cm diameter with 5 ml of fungal filtrate from each tested isolate. The control group consisted of 500 eggs of A. galli with 10 ml of distilled water on each Petri dish (assay B). Fungal isolates were effective (P < 0.01) at destroying these eggs, showing a type 3 effect at the studied intervals. On the other hand, the crude extract of isolates (VC1 or VC4) reduced the number of A. galli eggs in the treated group compared with the control group by 64.1% and 56.5%, respectively. The results of the present study show that P. chlamydosporia is effective at destroying eggs of A. galli and could therefore be used in the biological control of nematodes.


Asunto(s)
Ascaridia/efectos de los fármacos , Ascaridiasis/veterinaria , Mezclas Complejas/farmacología , Hypocreales/química , Enfermedades de las Aves de Corral/parasitología , Animales , Ascaridia/crecimiento & desarrollo , Ascaridia/microbiología , Ascaridiasis/microbiología , Recuento de Huevos de Parásitos , Control Biológico de Vectores/métodos
16.
Rev. ciênc. farm. básica apl ; Rev. ciênc. farm. básica apl;32(2)ago. 2011.
Artículo en Portugués | LILACS | ID: lil-604988

RESUMEN

Os objetivos deste estudo foram determinar as atividades antioxidante e antimicrobiana de extratos de cascas e folhas de uma notável árvore da Caatinga (semi-árido brasileiro), usado em remédios populares, Ziziphus joazeiro Mart. A atividade antioxidante foi avaliada através do método de captação pelo DPPH, enquanto a atividade antimicrobiana foi avaliada pelo método de difusão em ágar seguido pela determinação da concentração inibitória mínima (CMI). Os resultados mostraram que ambos os extratos de Z. joazeiro possuem atividade antioxidante com EC50 de 461,88 e 1.743,05mg/mL para as folhas e casca, respectivamente. As amostras foram ativas contra 70% das bactérias testadas. O extrato de folhas mostrou CMI entre 0,25-0,5 mg/mL contra Micrococcus luteus e entre 0,125-0,250 mg/mL contra Mycobacterium smegmatis, enquanto o extrato da casca apresentou CMI entre 0,5-1,0 mg /ml M. smegmatis.


The objectives of this study were to determine the antioxidant and antimicrobial activities of ethanolic extracts of the bark and leaves of a notable tree of the caatinga (Brazilian semiarid scrubland) used in many popular remedies, Ziziphus joazeiro Mart. The antioxidant activity was assessed by the DPPH free-radical scavenging assay, while the antimicrobial activity, against a range of Gram positive and negative bacteria and a yeast, was determined by the agar disk diffusion method, followed by an assay of the minimum inhibitory concentration (MIC). The results showed that both extracts of Z. joazeiro have antioxidant activity, the EC50 of leaf extract being 461.88 and that of bark 1743.05 mg/mL, with respect to DPPH absorbance in a standard assay. Samples were active against 70% of the bacterial species tested. The leaf extract showed MICs of 0.25-0.5 mg/mL against Micrococcus luteus and 0.125-0.250 mg/mL against Mycobacterium smegmatis, while the bark extract showed a MIC of 0.5-1.0 mg/mL against M. smegmatis.


Asunto(s)
Antiinfecciosos , Antioxidantes , Extractos Vegetales , Estructuras de las Plantas , Ziziphus
17.
J Helminthol ; 85(2): 164-70, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20682085

RESUMEN

Protease production from Duddingtonia flagrans (isolate AC001) was optimized and the larvicidal activity of the enzymatic extract was evaluated on infective horse cyathostomin larvae (L3). Duddingtonia flagrans was grown in liquid medium with eight different variables: glucose, casein, bibasic potassium phosphate (K2HPO4), magnesium sulphate (MgSO4), zinc sulphate (ZnSO4), ferrous sulphate (FeSO4), copper sulphate (CuSO4) and temperature. The Plackett-Burman analysis showed a significant influence of MgSO4, CuSO4 and casein (P < 0.05) on protease production by D. flagrans in liquid medium. Central composite design indicated that the highest proteolytic activity was 39.56 U/ml as a function of the concentrations of casein (18.409 g/l), MgSO4 (0.10 g/l) and CuSO4 (0.50 mg/l). A significant difference (P < 0.01) was found for the larval number between the treated and control groups at the end of the experiment. A reduction of 95.46% in the number of free-living larvae was found in the treated group compared with the control. The results of this study suggest that protease production by D. flagrans (AC001) in liquid medium was optimized by MgSO4, CuSO4 and casein, showing that the optimized enzymatic extract exerted larvicidal activity on cyathostomins and therefore may contribute to large-scale industrial production.


Asunto(s)
Antihelmínticos/metabolismo , Antihelmínticos/farmacología , Duddingtonia/enzimología , Péptido Hidrolasas/metabolismo , Péptido Hidrolasas/farmacología , Estrongílidos/efectos de los fármacos , Animales , Antihelmínticos/aislamiento & purificación , Medios de Cultivo/química , Duddingtonia/crecimiento & desarrollo , Caballos , Larva/efectos de los fármacos , Péptido Hidrolasas/aislamiento & purificación , Proteolisis , Análisis de Supervivencia
18.
Vet Parasitol ; 169(1-2): 123-7, 2010 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-20097478

RESUMEN

An assessment was made of the ovicidal activity of egg-parasitizing fungi Pochonia chlamydosporia (isolates VC1 and VC4) and Paecilomyces lilacinus on Toxocara canis eggs in vitro. The fungal isolates were inoculated onto Petri dishes with 2% water-agar (2% WA) and stored at 25 degrees C for 10 days in an incubator, in the dark. The control group was comprised of Petri dishes without fungi, containing the 2%WA medium only. Later, 1000 embryonated eggs were placed on the surface of the plates with fungal isolates and also on the control plates, and were then incubated at 25 degrees C for 7, 14 and 21 days. At these intervals, the eggs were retrieved and underwent percentage assessment according to the following parameters: no changes; type 1 effect, physiological and biochemical effect without morphological damage to eggshell, with visualization of hyphae adhered to eggshell; type 2 effect, lytic effect with morphological changes in embryo and eggshell, without hyphal penetration through the eggshell; type 3 effect, lytic effect with morphological changes in embryo and eggshell, with hyphal penetration and internal egg colonization. All the fungal isolates showed ovicidal activity (type 3 effect) on T. canis eggs, with 13.8%, 20.5% and 20.3% of ovicidal activity using P. chlamydosporia isolate VC1 after 7, 14 and 21 days, whereas isolate VC4 showed 15.2%, 19.0% and 21.7% of ovicidal activity at the same time intervals. P. lilacinus showed ovicidal activity of 12.3%, 18.8% and 20.0% after 7, 14 and 21 days. P. chlamydosporia and P. lilacinus were effective in vitro on T. canis eggs and can be considered a potential candidate to biological controller of those nematodes.


Asunto(s)
Hypocreales/fisiología , Paecilomyces/fisiología , Control Biológico de Vectores , Toxocara canis/microbiología , Animales , Enfermedades de los Perros/prevención & control , Perros , Femenino , Modelos Lineales , Factores de Tiempo , Toxocariasis/prevención & control , Cigoto/microbiología
19.
Appl Biochem Biotechnol ; 160(6): 1797-807, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19475517

RESUMEN

Clavulanic acid (CA) is a beta-lactam antibiotic, which has a potent beta-lactamase inhibiting activity. The influence of five variables, namely pH (6.0, 6.4, and 6.8), temperature (28 degrees C, 30 degrees C, and 32 degrees C), agitation intensity (150, 200, and 250 rpm), glycerol concentration (5.0, 7.5, and 10 g/L) and soybean flour concentration (5.0, 12.5, and 20 g/L), on CA production by a new isolate of Streptomyces (DAUFPE 3060) was investigated in 250-mL Erlenmeyer flasks using a fractional factorial design. Temperature and soybean flour concentration were shown to be the two variables that exerted the most important effects on the production of CA at 95% confidence level. The highest CA concentration (494 mg/L) was obtained after 48 h at 150 rpm, 32 degrees C, pH 6.0, 5.0 g/L glycerol, and 20 g/L soybean flour concentrations. Under these conditions, the yields of biomass and product on consumed substrate were 0.26 g(X)/g(S) and 64.3 mg(P)/g(S), respectively. Fermentations performed in 3.0-L bench-scale fermenter allowed increasing the CA production by about 60%.


Asunto(s)
Ácido Clavulánico/biosíntesis , Streptomyces/metabolismo , Biomasa , Reactores Biológicos/microbiología , Carbono/farmacología , Fermentación/efectos de los fármacos , Harina , Glicerol/farmacología , Concentración de Iones de Hidrógeno/efectos de los fármacos , Nitrógeno/farmacología , Streptomyces/efectos de los fármacos , Factores de Tiempo
20.
J Helminthol ; 84(1): 21-5, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19570314

RESUMEN

The action of four fungal isolates of the species Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a) and Pochonia chlamydosporia (VC1 and VC4) on eggs of Oxyuris equi and Austroxyuris finlaysoni was evaluated in two assays (A and B). Eggs of O. equi (Test A) and A. finlaysoni (Test B) were plated on Petri dishes with 2% water-agar with grown fungal isolates and control without fungus. After 5, 10 and 15 days, 100 eggs were collected and classified according to the following parameters: type 1 effect, physiological and biochemical effect without morphological damage to the eggshell; type 2 effect, lytic effect with morphological alteration of the eggshell and embryo; and type 3 effect, lytic effect with morphological alteration of the eggshell and embryo, hyphal penetration and internal egg colonization. Pochonia chlamydosporia isolates VC1 and VC4 showed ovicidal activity for type 1, 2 and 3 effects on eggs of O. equi and eggs of A. finlaysoni. In vitro assays A and B showed that P. chlamydosporia had a negative influence on eggs of O. equi and A. finlaysoni and can be considered as a potential biological control agent of nematodes.


Asunto(s)
Hypocreales/fisiología , Nematodos/microbiología , Control Biológico de Vectores/métodos , Animales , Ascomicetos/fisiología , Femenino , Masculino , Nematodos/fisiología , Óvulo/microbiología , Óvulo/fisiología
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