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BACKGROUND AND PURPOSE: Cerebral amyloid angiopathy is characterized by amyloid ß deposition in leptomeningeal and superficial cortical vessels. Cognitive impairment is common and may occur independent of concomitant Alzheimer disease neuropathology. It is still unknown which neuroimaging findings are associated with dementia in cerebral amyloid angiopathy and whether they are modulated by sex. This study compared MR imaging markers in patients with cerebral amyloid angiopathy with dementia or mild cognitive impairment or who are cognitively unimpaired and explored sex-specific differences. MATERIALS AND METHODS: We studied 58 patients with cerebral amyloid angiopathy selected from the cerebrovascular and memory outpatient clinics. Clinical characteristics were collected from clinical records. Cerebral amyloid angiopathy was diagnosed on MR imaging on the basis of the Boston criteria. Visual rating scores for atrophy and other imaging features were independently assessed by 2 senior neuroradiologists. RESULTS: Medial temporal lobe atrophy was higher for those with cerebral amyloid angiopathy with dementia versus those cognitively unimpaired (P = .015), but not for those with mild cognitive impairment. This effect was mainly driven by higher atrophy in men with dementia, compared with women with and without dementia (P = .034, P = .012; respectively) and with men without dementia (P = .012). Enlarged perivascular spaces in the centrum semiovale were more frequent in women with dementia versus men with and without dementia (P = .021, P = .011; respectively) and women without dementia (P = .011). CONCLUSIONS: Medial temporal lobe atrophy was more prominent in men with dementia, whereas women showed a higher number of enlarged perivascular spaces in the centrum semiovale. Overall, this finding suggests differential pathophysiologic mechanisms with sex-specific neuroimaging patterns in cerebral amyloid angiopathy.
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Enfermedad de Alzheimer , Angiopatía Amiloide Cerebral , Masculino , Humanos , Femenino , Péptidos beta-Amiloides , Angiopatía Amiloide Cerebral/complicaciones , Angiopatía Amiloide Cerebral/diagnóstico por imagen , Angiopatía Amiloide Cerebral/patología , Enfermedad de Alzheimer/patología , Imagen por Resonancia Magnética , Atrofia/complicacionesRESUMEN
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.
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Nowadays, pharmaceutical companies are facing several challenges with the development and approval of new biological products. The unique properties of several fluorinated ionic liquids (FILs), such as their high surfactant power in aqueous solutions, their chemical and biological stability, and low toxicity, favor their application in the pharmaceutical industry. Furthermore, the numerous combinations between cations and anions, in the FILs design, enlarge the possibilities to construct a successful delivery system. Several FILs also proved to not affect the activity, stability, and secondary structure of the therapeutic protein lysozyme. This work aims to study the aggregation behavior of distinct FILs in the protein suitable medium, in the presence or absence of lysozyme. Besides, different incubation conditions were tested to guarantee the optimal enzymatic activity of the protein at more stable delivery systems. Following the optimization of the incubation conditions, the quantification of the encapsulated lysozyme was performed to evaluate the encapsulation efficiency of each FIL-based system. The release of the protein was tested applying variables such as time, temperature, and ultrasound frequency. The experimental results suggest that the aggregation behavior of FILs is not significantly influenced by the protein and/or protein buffer and supports their application for the design of delivery systems with high encapsulation efficiencies, maintaining the biological activity of either encapsulated and released protein.
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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.
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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 C57BLRESUMEN
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.
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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 , OvariectomíaRESUMEN
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.
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Graphene is considered a promising substance in applications related to the capture and reduction of the environmental impact of fluorinated gases. However, further research is still required to explore all related possibilities. In this work, the potential use in this context of nanofluids (NFs), obtained by dispersing graphene nanosheets in fluorinated ionic liquids (FILs) is investigated. As a starting step, a thermal and structural characterization for this type of IoNanofluids (IoNFs) is presented. The highly nanostructured nature of FILs has been recently demonstrated. The presence of fluorinated moieties is responsible for enhancing the accommodation of solutes such as small gases. The strong tendency to self-assemble forming continuous and supramolecular structures, and the versatility to rearrange in several conformational features allows the stabilization of nano colloidal systems. It is essential to perform a comprehensive study of their structural features to understand the behavior of this type of heterogeneous systems. Therefore, we present screening on the phase and structural behavior of these novel IoNFs to discover and develop optimized systems where FILs turn out to be advantageous. Thermogravimetric analysis (TGA) was employed to evaluate IoNFs mass losses with temperature, and their solid-fluid phase transitions were located using a differential scanning calorimeter (DSC). Their rheological properties were also determined through oscillatory experiments, obtaining the viscous and loss moduli. In addition, the structural percolation transition was also identified.
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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.
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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 & purificaciónRESUMEN
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.
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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 fármacosRESUMEN
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.
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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 , ZimosanRESUMEN
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.
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Animales , Adaptación Fisiológica/fisiología , Mytilidae/fisiología , América del Sur , Manejo de Especímenes , Temperatura , Agua , Análisis de Varianza , Mytilidae/química , Glucógeno/análisis , Aclimatación/fisiologíaRESUMEN
The shape and size of nanoparticles are important parameters affecting their biodistribution, bioactivity, and toxicity. The high-throughput characterisation of the nanoparticle shape in dispersion is a fundamental prerequisite for realistic in vitro and in vivo evaluation, however, with routinely available bench-top optical characterisation techniques, it remains a challenging task. Herein, we demonstrate the efficacy of a single particle extinction and scattering (SPES) technique for the in situ detection of the shape of nanoparticles in dispersion, applied to a small library of anisotropic gold particles, with a potential development for in-line detection. The use of SPES paves the way to the routine quantitative analysis of nanoparticles dispersed in biologically relevant fluids, which is of importance for the nanosafety assessment and any in vitro and in vivo administration of nanomaterials.
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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.
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Adaptación Fisiológica/fisiología , Mytilidae/fisiología , Aclimatación/fisiología , Análisis de Varianza , Animales , Glucógeno/análisis , Mytilidae/química , América del Sur , Manejo de Especímenes , Temperatura , AguaRESUMEN
The range of possible nanostructures is so large and continuously growing, that collating and unifying the knowledge connected to them, including their biological activity, is a major challenge. Here we discuss a concept that is based on the connection of microscopic features of the nanomaterials to their biological impacts. We also consider what would be necessary to identify the features that control their biological interactions, and make them resemble each other in a biological context.
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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.
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This paper reports the thermal, thermodynamic, thermophysical and surface properties of eight ionic liquids with fluorinated alkyl side chain lengths equal or greater than four carbon atoms. Melting and decomposition temperatures were determined together with experimental densities, surface tensions, refractive indices, dynamic viscosities and ionic conductivities in a temperature interval ranging from 293.15 to 353.15 K. The surface properties of these fluorinated ionic liquids were discussed and several thermodynamic functions, as well as critical temperatures, were estimated. Coefficients of isobaric thermal expansion, molecular volumes and free volume effects were calculated from experimental values of density and refractive index and compared with previous data. Finally, Walden plots were used to evaluate the ionicity of the investigated ionic liquids.
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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.
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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 fármacosRESUMEN
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.
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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/metabolismoRESUMEN
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/metabolismoRESUMEN
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.