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PURPOSE: For growth of methylotrophic yeast, glycerol is usually used as a carbon source. Glucose is used in some cases, but not widely consumed due to strong repressive effect on AOX1 promoter. However, glucose is still considered as a carbon source of choice since it has low production cost and guarantees growth rate comparable to glycerol. RESULTS: In flask cultivation of the recombinant yeast, Pichia pastoris GS115(pPIC9K-appA38M), while methanol induction point(OD600) and methanol concentration significantly affected the phytase expression, glucose addition in induction phase could enhance phytase expression. The optimal flask cultivation conditions illustrated by Response Surface Methodology were 10.37 OD600 induction point, 2.02 h before methanol feeding, 1.16% methanol concentration and 40.36µL glucose feeding amount(for 20 mL culture volume) in which the expressed phytase activity was 613.4 ± 10.2U/mL, the highest activity in flask cultivation. In bioreactor fermentation, the intermittent glucose feeding showed several advantageous results such as 68 h longer activity increment, 149.2% higher cell density and 200.1% higher activity compared to the sole methanol feeding method. These results implied that remaining glucose at induction point might exhibit a positive effect on the phytase expression. CONCLUSION: Glucose intermittent feeding could be exploited for economic phytase production and the other recombinant protein expression by P. pastoris GS115.
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6-Fitase , Reatores Biológicos , Fermentação , Glucose , Metanol , Proteínas Recombinantes , 6-Fitase/genética , 6-Fitase/metabolismo , Glucose/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Metanol/metabolismo , Reatores Biológicos/microbiologia , Meios de Cultura/química , Meios de Cultura/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo , Saccharomycetales/crescimento & desenvolvimento , Pichia/genética , Pichia/metabolismo , Pichia/crescimento & desenvolvimento , Expressão GênicaRESUMO
The intricate mechanisms governing brain health and function have long been subjects of extensive investigation. Recent research has shed light on two pivotal systems, the glymphatic system and the endocannabinoid system, and their profound role within the central nervous system. The glymphatic system is a recently discovered waste clearance system within the brain that facilitates the efficient removal of toxic waste products and metabolites from the central nervous system. It relies on the unique properties of the brain's extracellular space and is primarily driven by cerebrospinal fluid and glial cells. Conversely, the endocannabinoid system, a multifaceted signaling network, is intricately involved in diverse physiological processes and has been associated with modulating synaptic plasticity, nociception, affective states, appetite regulation, and immune responses. This scientific review delves into the intricate interconnections between these two systems, exploring their combined influence on brain health and disease. By elucidating the synergistic effects of glymphatic function and endocannabinoid signaling, this review aims to deepen our understanding of their implications for neurological disorders, immune responses, and cognitive well-being.
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Sistema Glinfático , Doenças do Sistema Nervoso , Humanos , Sistema Glinfático/metabolismo , Endocanabinoides/metabolismo , Encéfalo/metabolismo , Sistema Nervoso Central , Doenças do Sistema Nervoso/metabolismoRESUMO
Introduction: Sarcopenia is a highly prevalent disease associated with adverse outcomes such as falls, disability, and death. The current international consensuses agree that muscle strength, muscle mass, and gait speed must be included in the definition. However, these proposed criteria require objective measurements that are not available for most populations. Since the timely identification of sarcopenia is a priority, several subjective screening scales have been developed; however, they have some limitations due to their low sensitivity. The objective of this work was to develop and validate SARCO-GS, a new short scale to screen sarcopenia that is affordable, easy, and accessible for all clinical care settings. Methods and materials: The development of the SARCO-GS included four stages: (1) Review and analysis of documentary sources, (2) Contextualization of the theoretical model of sarcopenia, (3) Scale conformation, and (4) Reliability and validity analyses. SARCO-GS was validated in the FraDySMex study, which is a longitudinal cohort of community-dwelling adults. Results: In the studied population (n=852), the average age was 68.9 years (SD 10.21) and 80.1% of the participants were women. SARCO-GS is a seven-item scale with an innovative structure that included five subjective questions (gait speed, muscular strength, muscle mass) and two measurements of muscular strength and muscle mass (Chair stand test and calf circumference). The results regarding criterion validity showed that the cut-off point ≥ 3 had good sensitivity (77.68%) versus the EWGSOP2 consensus, with an adequate Area Under the Receiver Operating Characteristic (AUC) (0.73), in addition to showing higher values of sensitivity and AUC than SARC-F and SARC-CalF using as reference the same consensus. Furthermore, SARCO-GS presented good predictive validity for functional dependence (HR=2.22, p=0.046) and acceptable correlation with other related measurements (construct validity). Regarding reliability, the scale showed acceptable internal reliability (correlation between items and total score: 0.50 to 0.70). After the validation analysis, the scale was adapted to English. Conclusions: The SARCO-GS is a novel scale to screen sarcopenia with high sensitivity, good construct, predictive validity, and internal reliability that may be useful for health professionals in different clinical settings and for clinical research.
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Sarcopenia , Adulto , Humanos , Feminino , Idoso , Masculino , Sarcopenia/diagnóstico , Reprodutibilidade dos Testes , Força Muscular , Consenso , Pessoal de SaúdeRESUMO
Zika still poses a threat to global health owing to its association with serious neurological conditions and the absence of a vaccine and treatment. Sofosbuvir, an anti-hepatitis C drug, has shown anti-Zika effects in animal and cell models. Thus, this study aimed to develop and validate novel LC-MS/MS methods for the quantification of sofosbuvir and its major metabolite (GS-331007) in human plasma and cerebrospinal (CSF) and seminal fluid (SF), and apply the methods to a pilot clinical trial. The samples were prepared by liquid-liquid extraction and separated using isocratic mode on Gemini C18 columns. Analytical detection was performed using a triple quadrupole mass spectrometer equipped with an electrospray ionization source. The validated ranges for sofosbuvir were 0.5-2,000 ng/mL (plasma) and 0.5-100 ng/mL (CSF and SF), while for the metabolite they were 2.0-2,000 ng/mL (plasma), 5.0-200 ng/mL (CSF) and 10-1,500 ng/mL (SF). The intra-day and inter-day accuracies (90.8-113.8%) and precisions (1.4-14.8%) were within the acceptance range. The developed methods fulfilled all validation parameters concerning selectivity, matrix effect, carryover, linearity, dilution integrity, precision, accuracy and stability, confirming the suitability of the method for the analysis of clinical samples.
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Infecção por Zika virus , Zika virus , Animais , Humanos , Cromatografia Líquida/métodos , Limite de Detecção , Plasma , Reprodutibilidade dos Testes , Sofosbuvir , Espectrometria de Massas em Tandem/métodosRESUMO
By December 2021, the COVID-19 caused approximately 6.1 million deaths around the world. Several vaccines have been approved, but there is still a need for non-prophylactic treatments for COVID-19. Remdesivir is an antiviral drug approved for emergency use against COVID-19 in several countries, but one of the first clinical trials was inconclusive about the mortality reduction, although the drug showed a reduction in the recovery time of hospitalized patients. Thus, the present investigation revisits the clinical evidence of using remdesivir for COVID-19 treatment, patent status, pharmacology and chemistry. We found 184 families of patents in the Cortellis database, and concerning the clinical evidence, we retrieved 14 systematic reviews with meta-analysis involving remdesivir as a treatment for COVID-19, discussing the reduction of adverse events, hospitalization days, mortality rate and the mechanical ventilation period.
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Tratamento Farmacológico da COVID-19 , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/efeitos adversos , Humanos , SARS-CoV-2RESUMO
RESUMEN Introducción: La disautonomía es uno de los mecanismos fisiopatológicos principales que marcan el pronóstico de la cardiopatía isquémica y la insuficiencia cardíaca. La búsqueda de nuevas oportunidades de tratamiento requiere un conocimiento más profundo de los efectos cardíacos de la activación simpática crónica. Objetivos: Estudiar el tamaño del infarto y la función ventricular izquierda en un modelo de ratones transgénicos con sobreexpresión de la proteína Gs-α cardíaca en el contexto de la isquemia/reperfusión miocárdica y el infarto crónico. Material y métodos: Ratones transgénicos (TG) con sobreexpresión cardíaca de la subunidad alfa de la proteína Gs y sus respectivos controles wild-type (WT) fueron sometidos a isquemia miocárdica regional de 30 minutos con 2 horas de reperfusión (IR) o un infarto sin reperfusión (I) de 28 días de evolución. Se cuantificó el tamaño del infarto (TI) con cloruro de 2,3,5-trifeniltetrazolio y se evaluó la función ventricular izquierda mediante ecocardiografía y estudio hemodinámico. Cada grupo experimental estuvo acompañado por un grupo control (WT / TG Sham-2hrs y WT / TG Sham-28d). Resultados: No hubo diferencias significativas en el TI luego de la IR entre los ratones TG y WT (57,3 ± 3,5% vs 59,2±2,5%, respectivamente, p = NS). La frecuencia cardíaca en los ratones TG fue mayor durante el desarrollo de todo el protocolo. Con la infarto se observó un descenso de la fracción de eyección (WT: Sham-28d: 82 ± 2,4% vs I-28d: 44 ± 4% y TG: Sham-28d 89 ± 2% vs I-28d 42 ± 3%; p <0,05) conjuntamente con una disminución de la fracción de acortamiento (FA), y los cambios del área fraccional (CAF) del ventrículo izquierdo (VI) en comparación con los valores basales y sus respectivos grupos controles. Sin embargo, no se observaron diferencias entre los grupos WT y TG. Conclusión: la sobreexpresión de la proteína Gs-α cardíaca no aumenta el tamaño del infarto ni modifica la función ventricular izquierda en la isquemia/reperfusión aguda y en el infarto crónico en comparación con sus respectivos controles
ABSTRACT Background: Dysautonomia is one of the main pathophysiological mechanisms that define the prognosis of ischemic heart disease and heart failure. The search for new treatment opportunities requires a deeper understanding of the cardiac effects of chronic sympathetic activation. Objective: The aim of this study was to analyze left ventricular infarct size and ventricular function in a transgenic mouse model with overexpression of the cardiac Gs-α protein, in the context of myocardial ischemia/reperfusion and chronic infarction. Methods: Transgenic mice (TG) overexpressing cardiac Gs-α and its wild-type variant (WT) were subjected to 30-minute regional myocardial ischemia followed by 2-hour reperfusion (IR) or non- reperfusion (I) with a 28-day follow-up period. Infarct size (IS) was quantified using 2,3,5-triphenyltetrazolium chloride and left ventricular function was evaluated by echocardiography and LV catheterization. Each experimental group was accompanied by a control group (WT/TG Sham-2hrs and WT/TG Sham-28d). Results: There were no significant differences in IS after IR between TG and WT mice (57.3 ± 3.5% vs. 59.2 ± 2.5%, respectively, p = NS). The heart rate in TG mice was higher throughout the experiment. With ischemia, a in ejection fraction (WT: Sham-28d: 82 ± 2.4% vs. I-28d: 44 ± 4% and TG: Sham-28d 89 ± 2% vs. I-28d 42 ± 3%; p <0.05) was observed together with a decrease in shortening fraction and left ventricular fractional area changes compared with baseline values and their respective control (Sham) groups. However, no differences were observed between the WT and TG groups. Conclusions: Cardiac Gs-α protein overexpression does not increase infarct size or modify left ventricular function in acute ischemia / reperfusion and chronic infarction compared with their respective controls.
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Objetivo: Determinar la prevalencia del Síndrome de Burnout en trabajadores de empresa termoeléctrica en Choloma, Honduras, diciembre 2019. Diseño: Estudio descriptivo de corte transversal, realizado en empresa termoeléctrica, Choloma, Honduras, con una muestra a conveniencia de 35 trabajadores del departamento de Mantenimiento Mecánico Motores, tomando en cuenta los criterios de inclusión, utilizando un cuestionario que incluyó los elementos sociolaborales y los componentes del Maslach Burnout Inventory- General Survey. Resultados: La prevalencia de síndrome de burnout obtenida al aplicar la Escala de Maslach Burnout Inventory en los trabajadores técnicos de empresa termoeléctrica es de 14% (5); con puntuaciones altas en las dimensiones de agotamiento emocional y cinismo/despersonalización y puntuaciones bajas en eficacia profesional. De los trabajadores encuestados, un 29% (10) se encuentra en riesgo moderado, pues presentan niveles altos en las dimensiones agotamiento o cinismo/despersonalización, o baja en eficacia profesional. El 43% (15) se encuentra en riesgo leve, debido a que puntuaron medio en 1 o 2 dimensiones. Conclusiones: A pesar de que la prevalencia del Síndrome de Burnout definido es baja, es importante resaltar que existe un porcentaje considerablemente alto de trabajadores en riesgo de desarrollar síndrome de burnout. Además, se evidencia que los trabajadores con Síndrome de Burnout oscilan entre los 20 y los 39 años, siendo la población más joven afectada por el síndrome de burnout. Palabras clave: Síndrome de burnout, síndrome de quemado, Maslach Burnout Inventory, Maslach Burnout Inventory-General survey, Personal Técnico, empresa termoeléctrica, MBI-GS
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Esgotamento Profissional , Estresse Ocupacional , Esgotamento Psicológico , Doenças Profissionais , Epidemiologia Descritiva , Estudos Transversais , Saúde OcupacionalRESUMO
Resumen Objetivos: Determinar los factores asociados a la mortalidad de la hemorragia cerebral intraparenquimatosa espontánea en pacientes mayores de 50 años de edad que acudieron al Hospital Teodoro Maldonado Carbo durante el año 2017. Materiales y métodos: Mediante un estudio observacional retrospectivo analítico, con 92 pacientes diagnosticados de hemorragia intraparenquimatosa espontánea primaria, se evaluaron las características demográficas, factores de riesgo, factores de mal pronóstico y la mortalidad a los 30 días. La Intracerebral Hemorrage Grading Scale (ICH-GS) fue aplicada en nuestra población para evaluar la correlación de los puntajes obtenidos con la mortalidad a los 30 días. Resultados: De los 92 pacientes, (edad media: 69 años, media de la Escala de Coma de Glasgow [GCS] al ingreso: 11 puntos, media del volumen supratentorial e infratentorial 36.63 y 13.92 ml respectivamente, localización del hematoma más frecuente: tálamo [21,74%]). La mortalidad a 30 días fue del 31,40%. En un análisis univariado, GCS (odds ratio [OR] = 2.20, intervalo de confianza [IC] del 95% = 1.04- 4.65, p <0,04), volumen infratentorial (OR = 3.74 por ml, IC del 95% = 1.25 a 11.120, p <0.02) y la extensión ventricular (OR = 5.43, IC 95% = 1.40-22.35, P = 0.02), fueron predictores significativos para la mortalidad a los 30 días. La correlación de Pearson mostró correlaciones de 0.6556 entre el puntaje ICH-GS y la mortalidad a 30 días (P < 0.001). Conclusión: El puntaje de la GCS al ingreso junto con el volumen infratentorial y la extensión intraventricular son predictores significativos de mortalidad a los 30 días en pacientes con Hemorragia intracerebral (HIC) primaria espontánea, siendo útil para identificar pacientes de alto riesgo a corto plazo.
Abstract Objective: To determine the factors associated with the mortality of spontaneous intraparenchymal cerebral hemorrhage in patients over 50 years old who attended the Teodoro Maldonado Carbo Hospital during 2017. Methods: A retrospective analytical observational study of 92 patients of diagnosis of spontaneous primary intraparenchymal hemorrhage, 30-day mortality was evaluated according to demographic characteristics, risk factors and poor prognostic factors. The Intracerebral Hemorrhage Grading Scale (ICH-GS) scale was applied in our population to evaluate the correlation of the scores obtained with the 30-day mortality. Results: From 92 patients (mean age: 69 years, mean Glasgow Coma Scale [GCS] on admission: 10, mean supratentorial and infratentorial volume, respectively 36.63 and 13.92 ml, most common hematoma location: thalamus (21.74%). at 30 days it was [31.40%]). In a univariate analysis, GCS (odds ratio [OR] = 2.20, 95% confidence interval [CI] = 1.04- 4.65, p <0.04), infratentorial volume (OR) = 3.74 per ml, 95% CI = 1.25 to 11,120, p <0.02) and the ventricular extension was (OR = 5.43, 95% CI = 1.40-22.35, P = 0.02) were significant predictors for 30-day mortality The Pearson correlation showed correlations of 0.6556 between the IC-GS score and the 30-day mortality (P <0.001). Conclusions: The GCS score at admission together with infratentorial volume and intraventricular extension are significant predictors of 30-day mortality in patients with primary spontaneous Intracerebral Hemorrhage (ICH) being useful for identifying high-risk patients in the short term.
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Forest tree breeding has been successful at delivering genetically improved material for multiple traits based on recurrent cycles of selection, mating, and testing. However, long breeding cycles, late flowering, variable juvenile-mature correlations, emerging pests and diseases, climate, and market changes, all pose formidable challenges. Genetic dissection approaches such as quantitative trait mapping and association genetics have been fruitless to effectively drive operational marker-assisted selection (MAS) in forest trees, largely because of the complex multifactorial inheritance of most, if not all traits of interest. The convergence of high-throughput genomics and quantitative genetics has established two new paradigms that are changing contemporary tree breeding dogmas. Genomic selection (GS) uses large number of genome-wide markers to predict complex phenotypes. It has the potential to accelerate breeding cycles, increase selection intensity and improve the accuracy of breeding values. Realized genomic relationships matrices, on the other hand, provide innovations in genetic parameters' estimation and breeding approaches by tracking the variation arising from random Mendelian segregation in pedigrees. In light of a recent flow of promising experimental results, here we briefly review the main concepts, analytical tools and remaining challenges that currently underlie the application of genomics data to tree breeding. With easy and cost-effective genotyping, we are now at the brink of extensive adoption of GS in tree breeding. Areas for future GS research include optimizing strategies for updating prediction models, adding validated functional genomics data to improve prediction accuracy, and integrating genomic and multi-environment data for forecasting the performance of genetic material in untested sites or under changing climate scenarios. The buildup of phenotypic and genome-wide data across large-scale breeding populations and advances in computational prediction of discrete genomic features should also provide opportunities to enhance the application of genomics to tree breeding.
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One of the major issues in plant breeding is the occurrence of genotype × environment (GE) interaction. Several models have been created to understand this phenomenon and explore it. In the genomic era, several models were employed to improve selection by using markers and account for GE interaction simultaneously. Some of these models use special genetic covariance matrices. In addition, the scale of multi-environment trials is getting larger, and this increases the computational challenges. In this context, we propose an R package that, in general, allows building GE genomic covariance matrices and fitting linear mixed models, in particular, to a few genomic GE models. Here we propose two functions: one to prepare the genomic kernels accounting for the genomic GE and another to perform genomic prediction using a Bayesian linear mixed model. A specific treatment is given for sparse covariance matrices, in particular, to block diagonal matrices that are present in some GE models in order to decrease the computational demand. In empirical comparisons with Bayesian Genomic Linear Regression (BGLR), accuracies and the mean squared error were similar; however, the computational time was up to five times lower than when using the classic approach. Bayesian Genomic Genotype × Environment Interaction (BGGE) is a fast, efficient option for creating genomic GE kernels and making genomic predictions.
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Interação Gene-Ambiente , Genótipo , Modelos Genéticos , Teorema de Bayes , Valor Preditivo dos TestesRESUMO
Small molecules targeting kinases involved in B cell receptor signaling are showing encouraging clinical activity in chronic lymphocytic leukemia (CLL) patients. Fostamatinib (R406) and entospletinib (GS-9973) are ATP-competitive inhibitors designed to target spleen tyrosine kinase (Syk) that have shown clinical activity with acceptable toxicity in trials with CLL patients. Preclinical studies with these inhibitors in CLL have focused on their effect in patient-derived leukemic B cells. In this work we show that clinically relevant doses of R406 and GS-9973 impaired the activation and proliferation of T cells from CLL patients. This effect could not be ascribed to Syk-inhibition given that we show that T cells from CLL patients do not express Syk protein. Interestingly, ζ-chain-associated protein kinase (ZAP)-70 phosphorylation was diminished by both inhibitors upon TCR stimulation on T cells. In addition, we found that both agents reduced macrophage-mediated phagocytosis of rituximab-coated CLL cells. Overall, these results suggest that in CLL patients treated with R406 or GS-9973 T cell functions, as well as macrophage-mediated anti-tumor activity of rituximab, might be impaired. The potential consequences for CLL-treated patients are discussed.
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Indazóis/farmacologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Macrófagos/imunologia , Oxazinas/farmacologia , Pirazinas/farmacologia , Piridinas/farmacologia , Quinase Syk/antagonistas & inibidores , Linfócitos T/efeitos dos fármacos , Proteína-Tirosina Quinase ZAP-70/metabolismo , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Fagocitose/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Rituximab/farmacologia , Linfócitos T/imunologiaRESUMO
GS-9857, an inhibitor of the hepatitis C virus (HCV) nonstructural protein (NS) 3/4A, demonstrates potent activity against HCV genotypes 1-6 and improved coverage against commonly encountered NS3 resistance-associated variants (RAVs). In this study, the safety, tolerability, antiviral activity and pharmacokinetics (PK) of GS-9857 were evaluated in patients with chronic HCV genotype 1-4 infection. Patients with genotype 1-4 infection received placebo or once-daily GS-9857 at doses ranging from 50 to 300 mg for 3 days under fasting conditions. GS-9857 was well tolerated; all reported adverse events (AEs) were mild or moderate in severity. Diarrhoea and headache were the most commonly reported AEs. Grade 3 or 4 laboratory abnormalities were observed in 17% of patients receiving GS-9857; there were no Grade 3 or 4 abnormalities in alanine aminotransferase, aspartate aminotransferase or alkaline phosphatase levels. GS-9857 demonstrated potent antiviral activity in patients with chronic HCV infection, achieving mean and median maximum reductions in HCV RNA of ≥3 log10 IU/mL following administration of a 100-mg dose in patients with HCV genotype 1a, 1b, 2, 3 or 4 infection. The antiviral activity of GS-9857 was unaffected by the presence of pretreatment NS3 RAVs. In patients with genotype 1-4 infection, GS-9857 exhibited linear PK and was associated with a median half-life of 29-42 h, supporting once-daily dosing. Thus, the tolerability, efficacy and pharmacokinetic profile of GS-9857 support its further evaluation for treatment of patients with chronic HCV infection.
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Antivirais/administração & dosagem , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Compostos Macrocíclicos/administração & dosagem , Sulfonamidas/administração & dosagem , Adolescente , Adulto , Idoso , Ácidos Aminoisobutíricos , Antivirais/efeitos adversos , Antivirais/farmacocinética , Antivirais/farmacologia , Ciclopropanos , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Hepacivirus/isolamento & purificação , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Compostos Macrocíclicos/efeitos adversos , Compostos Macrocíclicos/farmacocinética , Compostos Macrocíclicos/farmacologia , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Prolina/análogos & derivados , Quinoxalinas , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Resultado do Tratamento , Carga Viral , Adulto JovemRESUMO
ABSTRACT Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis, during which unlimited spermatozoa is produced daily derived from SSCs in the testis throughout life of the male. Germline stem (GS) cells can be isolated from spermatogonia, which shared the characteristics of SSCs and embryonic stem cells (ESCs), and can be passaged stably in vitro. The study of GS cells contributes to understanding spermatogenesis process. However, little is known about the GS cells in domestic animals. Here, we report the successful establishment of a serum- and feeder-free system for multipotent male GS cells (mGSCs) from postnatal porcine testis. These cells expressed pluripotent markers, such as Oct4, Nanog, C-myc, and germline-specific markers including Vasa, CD90, CD49f, Gfrα1, Plzf and Dazl. Then we assayed the developmental potential of these cells in vitro. The porcine multipotent male germline stem cells (pmGSCs) can form embryoid bodies (EBs) by suspension culture. Immunofluorescence analysis showed that the EBs differentiated into neuron-specific enolase (NSE, ectoderm), α-actin (mesoderm), and Pdx1 (endoderm) positive cells. These cells induced by 10-6 M retinoic acid (RA) could be differentiated into spermatid-like cells which were positive for Acrosin. The pmGSCs has been cultured over 14 passages. Thus, we have established a long-term culture system for pmGSCs. This culture system provides a platform for the study of porcine mGSCs.
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El estudio de los factores de riesgo psicosocial recobra mayor relevancia ante las dinámicas impuestas por las economías globalizadas que generan entornos competitivos, aumentando las exigencias físicas, psicológicas y sociales de los trabajadores, quienes manifiestan diversas respuestas como el estrés laboral crónico también conocido como burnout o Síndrome de Quemarse por el Trabajo (SQT). El presente estudio tuvo como objetivo determinar la prevalencia del burnout y su relación con la presencia de factores de riesgo psicosocial laborales, percibidos como negativos en trabajadores de la Población Económicamente Activa (PEA) de Lima, Perú. Se encuestaron 339 trabajadores con la aplicación del Inventory General Survey (MBI-GS)¹, instrumento en su nueva versión, y la escala de Factores Psicosociales en el Trabajo², encontrándose prevalencia de burnout muy alto en la dimensión desgaste emocional o agotamiento (6,22%), asociado con 4 diferentes factores de riesgo psicosocial. El mayor factor de riesgo lo representan las exigencias laborales (p<0,004) y (OR= 6,979) con la dimensión cinismo de burnout; lo anterior deja de manifiesto que ante las exigencias laborales, los trabajadores expresan actitudes cínicas como mecanismo de defensa, por lo que se concluye que la prevalencia del burnout se relaciona significativamente con los factores de riesgo psicosocial, de ahí que las organizaciones deben prestar especial atención en estos factores.
The study of psychosocial risk factors regains more relevance to the dynamics imposed by globalized economies that generate competitive environments, increasing the physical, psychological and social needs of workers who manifest different answers as chronic job stress also known as Burnout or Syndrome of burning for Work (SQT). This study aimed to determine the prevalence of burnout and its relationship with the presence of occupational psychosocial risk factors, perceived as negative in workers of the Economically Active Population (EAP) in Lima, Peru. 339 workers were surveyed with the implementation of Inventory General Survey (MBI-GS)¹, instrument in its new version, and the scale of Psychosocial Factors in Work², finding high prevalence of burnout in the dimension emotional exhaustion (6,22% ), associated with 4 different psychosocial risk factors, the biggest risk factor is represented by work demands (p <0,004) and (OR = 6,979) with the cynicism of burnout dimension, the previous makes it clear that with work demands, workers expressed cynicism as a defense mechanism, so it is concluded that the prevalence of burnout was significantly related to psychosocial risk factors, hence that organizations should pay special attention to these factors.
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Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Esgotamento Profissional/epidemiologia , Emprego , Peru/epidemiologia , Fatores Socioeconômicos , Condições de Trabalho , Esgotamento Profissional/psicologia , Prevalência , Estudos Transversais , Inquéritos e Questionários , Fatores de Risco , Carga de TrabalhoRESUMO
The stomatal behavior of ferns provides an excellent system for disentangling responses to different environmental signals, which balance carbon gain against water loss. Here, we measured responses of stomatal conductance (gs ) to irradiance, CO2 , and vapor pressure deficit (VPD) for 13 phylogenetically diverse species native to open and shaded habitats, grown under high- and low-irradiance treatments. We tested two main hypotheses: that plants adapted and grown in high-irradiance environments would have greater responsiveness to all stimuli given higher flux rates; and that species' responsiveness to different factors would be correlated because of the relative simplicity of fern stomatal control. We found that species with higher light-saturated gs had larger responses, and that plants grown under high irradiance were more responsive to all stimuli. Open habitat species showed greater responsiveness to irradiance and CO2 , but lower responsiveness to VPD; a case of plasticity and adaptation tending in different directions. Responses of gs to irradiance and VPD were positively correlated across species, but CO2 responses were independent and highly variable. The novel finding of correlations among stomatal responses to different stimuli suggests coordination of hydraulic and photosynthetic signaling networks modulating fern stomatal responses, which show distinct optimization at growth and evolutionary time-scales.
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Gleiquênias/fisiologia , Estômatos de Plantas/fisiologia , Adaptação Fisiológica , Dióxido de Carbono , Costa Rica , Ecossistema , Gleiquênias/crescimento & desenvolvimento , Luz , Pressão de Vapor , ÁguaRESUMO
The inactivation of the chloroplast ascorbate peroxidases (chlAPXs) has been thought to limit the efficiency of the water-water cycle and photo-oxidative protection under stress conditions. In this study, we have generated double knockdown rice (Oryza sativa L.) plants in both OsAPX7 (sAPX) and OsAPX8 (tAPX) genes, which encode chloroplastic APXs (chlAPXs). By employing an integrated approach involving gene expression, proteomics, biochemical and physiological analyses of photosynthesis, we have assessed the role of chlAPXs in the regulation of the protection of the photosystem II (PSII) activity and CO2 assimilation in rice plants exposed to high light (HL) and methyl violagen (MV). The chlAPX knockdown plants were affected more severely than the non-transformed (NT) plants in the activity and structure of PSII and CO2 assimilation in the presence of MV. Although MV induced significant increases in pigment content in the knockdown plants, the increases were apparently not sufficient for protection. Treatment with HL also caused generalized damage in PSII in both types of plants. The knockdown and NT plants exhibited differences in photosynthetic parameters related to efficiency of utilization of light and CO2. The knockdown plants overexpressed other antioxidant enzymes in response to the stresses and increased the GPX activity in the chloroplast-enriched fraction. Our data suggest that a partial deficiency of chlAPX expression modulate the PSII activity and integrity, reflecting the overall photosynthesis when rice plants are subjected to acute oxidative stress. However, under normal growth conditions, the knockdown plants exhibit normal phenotype, biochemical and physiological performance.
Assuntos
Ascorbato Peroxidases/genética , Proteínas de Cloroplastos/genética , Oryza/genética , Estresse Oxidativo/fisiologia , Fotossíntese/genética , Proteínas de Plantas/genética , Ascorbato Peroxidases/metabolismo , Proteínas de Cloroplastos/metabolismo , Eletroforese em Gel Bidimensional , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Herbicidas/farmacologia , Isoenzimas/genética , Isoenzimas/metabolismo , Luz , Oryza/efeitos dos fármacos , Oryza/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Paraquat/farmacologia , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
INTRODUÇÃO: A primeira doença humana atribuída à resistência hormonal foi o pseudo-hipoparatireoidismo (PHP), uma doença rara caracterizada por hipocalcemia, hiperfosfatemia e níveis elevados de hormônio paratireoidiano (PTH) na presença de função renal normal, quadro condizente com resistência ao PTH. A classificação original do PHP leva em consideração a osteodistrofia hereditária de Albright (AHO): presente no PHP1a e ausente no PHP1b. Na medida em que as bases moleculares do PHP têm sido compreendidas, uma classificação baseada no genótipo tem surgido. Segundo ela, pacientes com PHP1a apresentam mutações na região codificadora da Gsalfa do GNAS e o padrão de herança é autossômico dominante relacionado à transmissão materna. Por outro lado, o PHP1b é caracterizado por alterações nas regiões diferencialmente metiladas (DMRs) do GNAS por mecanismos não completamente esclarecidos, limitando a previsão do seu padrão de herança. Pacientes que apresentam a AHO na ausência de resistência hormonal têm o diagnóstico de pseudopseudo-hipoparatireoidismo (PPHP) e seu padrão de herança é autossômico dominante relacionado à transmissão paterna de mutações na região codificadora da Gsalfa do GNAS. OBJETIVOS: Classificar 25 pacientes com PHP com base em defeitos no GNAS e caracterizar seu fenótipo. Pesquisar mutações no GNAS nos quatro pacientes com PPHP e também caracterizar seu fenótipo. MÉTODOS: A avaliação fenotípica incluiu análise das resistências hormonais, pesquisa de repercussões crônicas da hipocalcemia/hiperfosfatemia (calcificações em sistema nervoso central: SNC e catarata) e identificação da AHO. A análise do GNAS foi feita por sequenciamento automático e MLPA (região codificadora da Gsalfa) e por MS-MLPA (região regulatória: DMRs). RESULTADOS: Resistência ao PTH foi identificada nos 25 pacientes com PHP e resistência ao TSH em 17/25. Calcificações em SNC e catarata estiveram presentes em 18 e 10 pacientes com PHP, respectivamente. A...
BACKGROUND: The first human disease attributed to hormone resistance was pseudohypoparathyroidism (PHP), a rare disease characterized by hypocalcemia, hyperphosphatemia and elevated parathyroid hormone (PTH) levels in the presence of normal renal function, consistent picture of PTH resistance. The original classification of PHP takes into account the Albright hereditary osteodystrophy (AHO): present in PHP1a and absent in PHP1b. As the molecular bases of PHP have been understood, a classification based on genotype has emerged. According to it, PHP1a patients present mutations in the Gsalpha coding region of the GNAS and the pattern of inheritance is autosomal dominant related to maternal transmission. On the other hand, PHP1b is characterized by alterations in differentially methylated regions (DMRs) of the GNAS by mechanisms not completely clear, limiting the prediction of the pattern of inheritance. Patients who present AHO in the absence of hormone resistance have the diagnosis of pseudopseudohypoparathyroidism (PPHP) and their pattern of inheritance is autosomal dominant related to paternal transmission of mutations in the Gsalfa coding region of the GNAS. OBJECTIVE: To classify 25 patients with PHP based on GNAS molecular defects and to characterize their phenotype. To search for GNAS mutations in four patients with PPHP and also to characterize their phenotype. METHODS: The phenotypic evaluation included analysis of hormone resistances, research of chronic repercussions of hypocalcemia/hyperphosphatemia (calcifications in central nervous system: CNS and cataract) and identification of AHO. The analysis of the GNAS was done by automated sequencing and MLPA (Gsalphaa coding region) and by MS-MLPA (regulatory region: DMRs). RESULTS: PTH resistance was identified in 25 patients with PHP and TSH resistance in 17/25. Calcifications in CNS and cataract were present in 18 and 10 patients with PHP, respectively. AHO was characterized by: rounded face (n=18),...
Assuntos
Humanos , Masculino , Feminino , Hipocalcemia , Hormônio Paratireóideo , Pseudo-Hipoparatireoidismo , Pseudopseudo-HipoparatireoidismoRESUMO
The physiological responses of C4 species to simultaneous water deficit and low substrate temperature are poorly understood, as well as the recovery capacity. This study investigated whether the effect of these abiotic stressors is cultivar-dependent. The differential responses of drought-resistant (IACSP94-2094) and drought-sensitive (IACSP97-7065) sugarcane cultivars were characterized to assess the relationship between photosynthesis and antioxidant protection by APX and SOD isoforms under stress conditions. Our results show that drought alone or combined with low root temperature led to excessive energetic pressure at the PSII level. Heat dissipation was increased in both genotypes, but the high antioxidant capacity due to higher SOD and APX activities was genotype-dependent and it operated better in the drought-resistant genotype. High SOD and APX activities were associated with a rapid recovery of photosynthesis in IACSP94-2094 plants after drought and low substrate temperature alone or simultaneously.
Assuntos
Ascorbato Peroxidases/genética , Temperatura Baixa , Secas , Fotossíntese/genética , Saccharum/genética , Superóxido Dismutase/genética , Água , Adaptação Fisiológica/genética , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Genótipo , Fenótipo , Complexo de Proteína do Fotossistema II/metabolismo , Transpiração Vegetal , Saccharum/enzimologia , Saccharum/metabolismo , Estresse Fisiológico/genética , Superóxido Dismutase/metabolismoRESUMO
Müller cells are not only the main glial cell type in the retina but also latent progenitor/stem cells, which in pathological conditions can transdifferentiate to a neuronal phenotype and regenerate the neurons lost in a mature retina. Several signal transduction pathways can induce the dedifferentiation of mature Müller cells to a progenitor-like state, including that stimulated by glutamate. However, the precise molecular mechanisms by which terminally differentiated cells are initially primed to acquire multipotency remain unclear. In the present study, we have characterized early genetic and epigenetic events that occur immediately after glutamate-induced dedifferentiation of fully differentiated Müller cells is initiated. Using Müller cell-enriched cultures from postnatal rats, we demonstrate that glutamate triggers a rapid dedifferentiation response characterized by changes in cell morphology coupled to the induction of progenitor cell marker gene expression (e.g., nestin, lin28 and sox2) within 1h. Dedifferentiation involved the activation of N-methyl-d-aspartate and type II metabotropic glutamate receptors, as well as global DNA demethylation (evident through the decrease in methyl-CpG-binding protein 2 immunoreactivity) and an increase in gadd45-ß gene expression; although, early progenitor gene expression was only partially inhibited by pharmacological impairment of DNA methylation. Importantly, the expression of Müller glia identity genes (i.e., glutamine synthetase; cellular retinaldehyde binding protein, CRALBP) is retained through the process. Dedifferentiated Müller cells held an early neuronal differentiation potential similar to that observed in retinal progenitor-enriched cultures but, contrary to the latter, dedifferentiated Müller cells failed to further differentiate into mature photoreceptor lineages. We speculate that, in spite of the initial triggering of the dedifferentiation pathways, these cells may exhibit a certain degree of epigenetic memory that precludes them from further differentiation.