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Damiana (Turnera diffusa Willd. ex Schult.) is a species of plant used in traditional Mexican medicine for its aphrodisiac properties. Although it has a high commercial demand, both nationally and internationally, its sexual propagation is not usual due to the low percentage of seed germination. It has been proposed that ants play an important role in germination, due to the presence of elaiosomes. Therefore, the objectives of this study were to characterize the seed morphology of T. diffusa for agronomic purposes, analyze their viability, and evaluate their germination by simulating environmental conditions of an ant nest. For the morphological characterization, 30 seeds were selected and evaluated for the variables of color, size, and weight. Viability was evaluated with a tetrazolium test using two lots of seeds collected in 2016 and 2017, with different concentrations and three exposure times at 40°C. The germination of T. diffusa was evaluated under three pre-germination treatments and nine germination treatments. The results of the study showed that the seeds of T. diffusa have an average size of 0.725 mm long and 0.182 mm wide; the color of the seeds varies from brown to black when ripe and yellowish white when immature. There are no significant differences in the viability percentage (60%) for seeds collected in 2016 and 2017 (p = 0.20). On the other hand, there are significant differences between all the pre-germination and germination tests analyzed. Seeds of T. diffusa have the highest percentage of germination (36%) with the presence of elaiosome and 500 ppm of GA3. The germination interval of the seeds occurs over a period of six to 39 days. The application of GA3 in the germination of the seeds indicates that they present a physiological latency which was inhibited at concentrations of 500 and 300 ppm.
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Formigas , Turnera , Animais , Germinação , Formigas/fisiologia , Plantas , Sementes/fisiologiaRESUMO
Light and photoperiod are environmental signals that regulate flowering transition. In plants like Arabidopsis thaliana, this regulation relies on CONSTANS, a transcription factor that is negatively posttranslational regulated by phytochrome B during the morning, while it is stabilized by PHYA and cryptochromes 1/2 at the end of daylight hours. CO induces the expression of FT, whose protein travels from the leaves to the apical meristem, where it binds to FD to regulate some flowering genes. Although PHYB delays flowering, we show that light and PHYB positively regulate XAANTAL1 and other flowering genes in the shoot apices. Also, the genetic data indicate that XAL1 and FD participate in the same signaling pathway in flowering promotion when plants are grown under a long-day photoperiod at 22 °C. By contrast, XAL1 functions independently of FD or PIF4 to induce flowering at higher temperatures (27 °C), even under long days. Furthermore, XAL1 directly binds to FD, SOC1, LFY, and AP1 promoters. Our findings lead us to propose that light and temperature influence the floral network at the meristem level in a partially independent way of the signaling generated from the leaves.
Assuntos
Arabidopsis , Arabidopsis/genética , Febre , Meristema/genética , Fitocromo B , Temperatura , Fatores de Transcrição/genéticaRESUMO
Oxygenic photosynthesis is responsible for most of the fixation of atmospheric CO2. The microalgal community can transport atmospheric carbon into biological cycles in which no additional CO2 is created. This represents a resource to confront the actual climate change crisis. These organisms have evolved to adapt to several environments and different spectral distribution of light that may strongly influence their metabolism. Therefore, there is a need for development of photobioreactors specialized in addressing spectral optimization. Here, a multi-scale modular photobioreactor made from standard glass materials, ad hoc light circuits, and easily accessible, small commercial devices is described. The system is suitable to manage the principal culture variables of research in bioenergetics and photosynthesis. Its performance was tested by growing four evolutionary-distant microalgal species with different endosymbiotic scenarios: Chlamydomonas reinhardtii (Archaeplastida, green primary plastid), Polytomella parva (Archaeplastida, colorless plastid), Euglena gracilis (Discoba, green secondary plastid), and Phaeodactylum tricornutum (Stramenophiles, red secondary plastid). Our results show an improvement of biomass production, as compared to the traditional flask system. The modulation of the incident light spectra allowed us to observe a far-red adaptation in Euglena gracilis with a difference on paramylon production, and it also significantly increased the maximal cell density of the diatom species under green light. Together, these confirm that for photobioreactors with artificial light, manipulation of the light spectrum is a critical parameter for controlling the optimal performance, depending on the downstream goals.
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Triosephosphate isomerase (TIM) is an enzyme of the glycolysis pathway which exists in almost all types of cells. Its structure is the prototype of a motif called TIM-barrel or (α/ß)8 barrel, which is the most common fold of all known enzyme structures. The simplest form in which TIM is catalytically active is a homodimer, in many species of bacteria and eukaryotes, or a homotetramer in some archaea. Here we show that the purified homodimeric TIMs from nine different species of eukaryotes and one of an extremophile bacterium spontaneously form higher order aggregates that can range from 3 to 21 dimers per macromolecular complex. We analysed these aggregates with clear native electrophoresis with normal and inverse polarity, blue native polyacrylamide gel electrophoresis, liquid chromatography, dynamic light scattering, thermal shift assay and transmission electron and fluorescence microscopies, we also performed bioinformatic analysis of the sequences of all enzymes to identify and predict regions that are prone to aggregation. Additionally, the capacity of TIM from Trypanosoma brucei to form fibrillar aggregates was characterized. Our results indicate that all the TIMs we studied are capable of forming oligomers of different sizes. This is significant because aggregation of TIM may be important in some of its non-catalytic moonlighting functions, like being a potent food allergen, or in its role associated with Alzheimer's disease.
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Agregados Proteicos , Triose-Fosfato Isomerase/metabolismo , Cromatografia Líquida , Biologia Computacional/métodos , Difusão Dinâmica da Luz , Ativação Enzimática , Expressão Gênica , Cinética , Ligação Proteica , Multimerização Proteica , Sensibilidade e Especificidade , Especificidade da Espécie , Triose-Fosfato Isomerase/química , Triose-Fosfato Isomerase/genética , Triose-Fosfato Isomerase/isolamento & purificaçãoRESUMO
INTRODUCCIÓN. El principal factor para la correcta administración de medicación inhalada es la técnica en el uso del dispositivo para asegurar que el fármaco alcance la vía aérea y lograr mejoría clínica. OBJETIVOS. Determinar el porcentaje de pacientes que no realizan una correcta técnica, definir el error más frecuente, el grupo de edad con mayor número de errores y establecer si existe asociación entre exacerbaciones en el año previo y una técnica adecuada. MATERIALES Y MÉTODOS. Estudio observacional, de corte transversal que evaluó la técnica de uso del inhalador de dosis medida presurizado (pDMI) en 64 pacientes mayores de 18 años con diagnóstico definitivo de alguna enfermedad pulmonar crónica que usó como tratamiento un inhalador de dosis medida presurizado por técnica directa, atendido en la Consulta Externa del Servicio de Neumología del Hospital General del Sur del Instituto Ecuatoriano de Seguridad Social, la evaluación se realizó de acuerdo a los pasos descritos en el Consenso SEPAR-ALAT sobre terapia inhalada. RESULTADOS. El 85,0 % (64) presentaron errores durante el uso del inhalador, el error más frecuente fue no espirar hasta vaciar los pulmones, los mayores de 65 años presentaron 4 errores, aquellos que no exacerbaron en el año previo tuvieron 2 errores y se demostró que al realizar una correcta técnica inhalatoria disminuyó el numeró de exacerbaciones OR 0,56 IC (-0,82; 1,95). CONCLUSIÓN. Se demostró el alto porcentaje de pacientes que no realizaron una técnica inhalatoria adecuada en el uso del dispositivo, de ahí la importancia de realizar un entrenamiento previo, para lograr una terapia efectiva.
INTRODUCTION. The main factor for the correct administration of inhaled medication is the technique in the use of the device to ensure that the drug reaches the airway and achieve clinical improvement. OBJECTIVES. Determine the percentage of patients who do not perform a correct technique, define the most frequent error, the age group with the greatest number of errors and establish if there is an association between exacerbations in the previous year and an adequate technique. MATERIALS AND METHODS. An observational, cross-sectional study that evaluated the technique of using the pressurized metered dose inhaler (pDMI) in 64 patients over 18 years of age with a definitive diagnosis of a chronic lung disease that used as a treatment a pressurized metered dose inhaler by direct technique, attended in the External Consultation of the Pulmonology Service of the General Hospital of the South of the Ecuadorian Social Security Institute, the evaluation was carried out according to the steps described in the SEPAR-ALAT Consensus on inhaled therapy. RESULTS. 85,0% (64) presented errors while using the inhaler, the most frequent error was not exhaling until the lungs were emptied, those over 65 presented 4 errors, those who did not exacerbate in the previous year had 2 errors and it was shown that when performing a correct inhalation technique, the number of exacerbations decreased OR 0.56 IC (-0.82; 1.95). CONCLUSION. The high percentage of patients who did not perform an appropriate inhalation technique in the use of the device was demonstrated, hence the importance of prior training, to achieve effective therapy.
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Humanos , Masculino , Feminino , Adulto , Terapia Respiratória , Adulto , Aerossóis , Pneumopatias , Erros de Medicação , Asma , Doença Pulmonar Obstrutiva CrônicaRESUMO
Triosephosphate isomerase is the fifth enzyme in glycolysis and its canonical function is the reversible isomerization of glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. Within the last decade multiple other functions, that may not necessarily always involve catalysis, have been described. These include variations in the degree of its expression in many types of cancer and participation in the regulation of the cell cycle. Triosephosphate isomerase may function as an auto-antigen and in the evasion of the immune response, as a factor of virulence of some organisms, and also as an important allergen, mainly in a variety of seafoods. It is an important factor to consider in the cryopreservation of semen and seems to play a major role in some aspects of the development of Alzheimer's disease. It also seems to be responsible for neurodegenerative alterations in a few cases of human triosephosphate isomerase deficiency. Thus, triosephosphate isomerase is an excellent example of a moonlighting protein.
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Anemia Hemolítica Congênita não Esferocítica/veterinária , Doenças dos Animais/enzimologia , Erros Inatos do Metabolismo dos Carboidratos/veterinária , Triose-Fosfato Isomerase/deficiência , Triose-Fosfato Isomerase/metabolismo , Anemia Hemolítica Congênita não Esferocítica/tratamento farmacológico , Anemia Hemolítica Congênita não Esferocítica/metabolismo , Doenças dos Animais/tratamento farmacológico , Animais , Erros Inatos do Metabolismo dos Carboidratos/tratamento farmacológico , Erros Inatos do Metabolismo dos Carboidratos/metabolismo , Fosfato de Di-Hidroxiacetona/metabolismo , Gliceraldeído 3-Fosfato/metabolismo , Glicólise , HumanosRESUMO
Resumen La corteza pre-frontal es la base de las habilidades mentales de mayor complejidad del desarrollo humano. En su proceso de evaluación, la escala EFECO brinda un importante aporte para valorar su estado. En investigaciones previas se ha estudiado esta escala con su configuración de 67 ítems, narrativa centrada en el déficit y evaluación de 8 funciones ejecutiva. En esta investigación se presentan los siguientes aportes: una nueva versión de la escala, centrada en su narrativa en la habilidad ejecutiva, propuesta de ítems para valorar la función ejecutiva de verificación y una versión resumida de la escala en 42 ítems. En el estudio participaron 118 adultos saludables entre 18 y 25 años de edad (M edad = 20.72, DE = 1.65). En los resultados se encontró que la escala EFECO II-VC (versión modificada y completa) obtuvo como consistencia interna α = .96 y sus sub-escalas consistencia interna entre α = .64 y .81. La escala EFECO II-VR (versión modificada y resumida) obtuvo α = .94 y sus sub-escalas entre α = .68 y .79. La consistencia interna de los factores en los que se engloban las funciones ejecutivas se presentaron adecuados: el sistema supervisor de la cognición II-VC α = .93 y II-VR α = .70, mientras que el sistema supervisor de la conducta II-VC α = .93 y II-VR α = .81. Las correlaciones entre las funciones ejecutivas valoradas con ambas escalas fueron entre medianas y grandes r = .36 y .94. Se cierra el trabajo discutiendo el aporte clínico y científico de la modificación de la escala EFECO.
Abstract The pre-frontal cortex is the basis of the most complex mental abilities of human development. In its evaluation process, the EFECO scale provides an important contribution to assess its status. In previous investigations this scale has been studied with its configuration of 67 items, narrative focused on the deficit and evaluation of 8 executive functions. This research presents a new version of the scale, centered on its narrative in executive ability, proposed items to assess executive verification function and a summarized version of 42 items. The study included 118 healthy adults between 18 and 25 years of age (M age = 20.72, SD = 1.65). In the results it was found that the EFECO II-VC scale (modified and complete version) obtained as internal consistency α = .96 and its sub-scales internal consistency between α = .64 and .81. The EFECO II-VR scale (modified and summarized version) obtained α = .94 and its sub-scales between α = .68 and .79. The internal consistency of the factors in which the executive functions are included were adequate: the supervisory system of cognition II-VC α = .93 and II-VR α = .70, while the supervisor system of behavior II- VC α = .93 and II-VR α = .81. The correlations between the executive functions assessed with both scales were between medium and large r = .36 and .94. The work is closed discussing the clinical and scientific contribution of the modification of the EFECO scale.
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RESUMEN En este artículo se reporta un estudio en el cual se adaptó y validó tres tareas experimentales (SIMON, Go/No-Go y Stroop Victoria) para valorar el control inhibitorio y control de la interferencia en una muestra de estudiantes ecuatorianos. La muestra estuvo conformada por 100 estudiantes entre 6 y 15 años de edad (M=10,13 años, DE= 2,48) pertenecientes al sistema educativo público de Ecuador. El proceso que se siguió en la adaptación y validación fue mediante la traducción lingüística de los experimentos, posteriormente se siguió un juicio de expertos y un estudio piloto. En los resultados se encontró que no existen diferencias estadísticamente significativas en las medidas que valoran el control inhibitorio y de la interferencia considerando como factores de comparación las variables sociodemográficas de los participantes. En el análisis correlacional se encontró una asociación estadísticamente significativa entre las mediciones de los experimentos. Se concluye analizando las asociaciones encontradas y subrayando la necesidad de continuar aportando evidencia en la línea de investigación de adaptación y validación de reactivos de uso en la evaluación neuropsicológica.
ABSTRACT In this article we report a study in which three experimental tasks (SIMON, Go / No-Go and Stroop Victoria) were adapted and validated to evaluate the inhibitory control and interference control in a sample of Ecuadorian students. The sample consisted of 100 students between 6 and 15 years old (M = 10.13 years, SD = 2.48) belonging to the public education system of Ecuador. The process followed in the adaptation and validation was through the linguistic translation of the experiments, followed by an expert judgment and a pilot study. In the results it was found that there are no statistically significant differences in the measures that assess the inhibitory control and the interference considering the sociodemographic variables of the participants as comparison factors. In the correlation analysis we found a statistically significant association between the measurements of the experiments. We conclude by analyzing the associations found and underlining the need to continue providing evidence in the research line of adaptation and validation of test for using in neuropsychological evaluation.
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BACKGROUND: Streptococcus agalactiae or group B Streptococcus (GBS) has been recognized as a lethal pathogen in neonates worldwide. S. agalactiae infections also severely affect pregnant women and immunosuppressed adults with substantial attributable morbidity and mortality. However, in Latin America, studies on the epidemiology and behaviour of S. agalactiae infections remain limited. METHODS: To better understand the behaviour of S. agalactiae infections in our region, we conducted a retrospective study to phenotypically describe S. agalactiae isolates collected in one of the largest hospitals in Colombia at two time periods: 1994-2001 and 2004-2012. The isolates were identified by biochemical analysis and tested for antimicrobial susceptibility. RESULTS: In 1994-2001 a total of 201 S. agalactiae isolates were found in urine 38.3%, vaginal exudates 27.8%, soft tissue 12.9%, and blood 8.5%. Susceptibility to ampicillin or penicillin was 94% whereas resistance to erythromycin and clindamycin were 2.8% and 5.2% respectively. In total 46 culture-positive cases of invasive infections were reported, 11 (24%) in neonates and 35 (76%) in adults. In 2004-2012 a total of 671 isolates were found in urine 47.8%, vaginal exudates 32.6%, soft tissue 2.7% and blood 9%. Susceptibility rates to ampicillin and penicillin were 98% whereas resistance to erythromycin and clindamycin were 12.5% and 9.4%. A total of 95 severe infections were reported: 12 (12.6%) were in neonates, 5 (5.3%) in children and 78 (82.1%) in adults. Over the 17-year study period the averaged prevalence of invasive S. agalactiae isolates was 17.4%. The estimated incidence for neonatal infections was 1.34 per 1000 livebirths (0.99 × 1000 livebirths for early- onset disease and 0.35 × 1000 livebirths for late- onset disease) whereas for non-pregnant adults the estimated incidence was 0.75 × 1000 admissions. CONCLUSIONS: A remarkable increase in bloodstream infections in immunosuppressed adults and a shift to early neonatal S. agalactiae infections were seen over time. We also found an increase in S. agalactiae resistance to erythromycin and clindamycin during the study period, and the emergence of penicillin-nonsusceptible isolates. Our findings are consistent with the global trends described elsewhere, reinforcing the need for S. agalactiae control measures in our region.
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Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Colômbia/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana , Feminino , Hospitais Universitários/estatística & dados numéricos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae/classificação , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Adulto JovemRESUMO
For a better comprehension of the structure-function relationship in proteins it is necessary to identify the amino acids that are relevant for measurable protein functions. Because of the numerous contacts that amino acids establish within proteins and the cooperative nature of their interactions, it is difficult to achieve this goal. Thus, the study of protein-ligand interactions is usually focused on local environmental structural differences. Here, using a pair of triosephosphate isomerase enzymes with extremely high homology from two different organisms, we demonstrate that the control of a seventy-fold difference in reactivity of the interface cysteine is located in several amino acids from two structurally unrelated regions that do not contact the cysteine sensitive to the sulfhydryl reagent methylmethane sulfonate, nor the residues in its immediate vicinity. The change in reactivity is due to an increase in the apparent pKa of the interface cysteine produced by the mutated residues. Our work, which involved grafting systematically portions of one protein into the other protein, revealed unsuspected and multisite long-range interactions that modulate the properties of the interface cysteines and has general implications for future studies on protein structure-function relationships.