ABSTRACT
Glycerol dehydrogenase (GldA) from Escherichia coli BW25113, naturally catalyzes the oxidation of glycerol to dihydroxyacetone. It is known that GldA exhibits promiscuity towards short-chain C2-C4 alcohols. However, there are no reports regarding the substrate scope of GldA towards larger substrates. Herein we demonstrate that GldA can accept bulkier C6-C8 alcohols than previously anticipated. Overexpression of the gldA gene in the knockout background, E. coli BW25113 ΔgldA, was strikingly effective converting 2 mM of the compounds: cis-dihydrocatetechol, cis-(1 S,2 R)- 3-methylcyclohexa-3,5-diene-1,2-diol and cis-(1 S,2 R)- 3-ethylcyclohexa-3,5-diene-1,2-diol, into 2.04 ± 0.21 mM of catechol, 0.62 ± 0.11 mM 3-methylcatechol, and 0.16 ± 0.02 mM 3-ethylcatechol, respectively. In-silico studies on the active site of GldA enlightened the decrease in product formation as the steric substrate demand increased. These results are of high interests for E. coli-based cell factories expressing Rieske non-heme iron dioxygenases, producing cis-dihydrocatechols, since such sough-after valuable products can be immediately degraded by GldA, substantially hampering the expected performance of the recombinant platform.
Subject(s)
Dioxygenases , Sugar Alcohol Dehydrogenases , Escherichia coli/genetics , Escherichia coli/metabolism , Sugar Alcohol Dehydrogenases/genetics , Dioxygenases/metabolism , Oxidation-Reduction , Glycerol/metabolismABSTRACT
OBJECTIVE: The purpose of this study was to assess knowledge and attitudes regarding end-of-life care (ELOC) among senior medical students at the University of Puerto Rico School of Medicine. METHODS: This was a cross-sectional study in which a questionnaire was administered to senior medical students from February through March 2017. The questionnaire included a knowledge and an attitudinal scale, and socio-demographic information. RESULTS: Eighty-one students with a mean age of 26 years participated. The majority were female (60.5%; n = 49) and most participants (81.5%; n = 63) correctly answered more than 70% of the questions on the knowledge scale. However, less than half (45.7%; n = 37) perceived that they had the knowledge necessary for EOLC. More male than female students (68.3% and 30.6%, respectively) felt that they were adequately prepared for working with patients requiring EOLC, a difference that was significant (P < .05). Most participants (81.0%; n = 66) had experienced the loss (due to death) of a significant person, and 66.0% (n = 53) felt that they had benefited from their experiences regarding being able to handle death. CONCLUSION: The study shows that participants had adequate knowledge about and positive attitudes toward EOLC but believed that they were lacking in knowledge, especially female students. These findings suggest the need to design and implement strategies to develop and strengthen self-efficacy in medical students regarding management of patients at the end of life.
Subject(s)
Health Knowledge, Attitudes, Practice , Students, Medical/psychology , Terminal Care/psychology , Adult , Cross-Sectional Studies , Female , Humans , Male , Puerto Rico , Schools, Medical , Surveys and QuestionnairesABSTRACT
A substantial influence of a magnetic field on the third-order nonlinear optical properties exhibited by aggregated networks of aligned carbon nanotubes (CNT) is reported by systematic measurements. A two-wave mixing was employed to explore and modulate the refractive index in the nanostructures in the nanosecond and picosecond regime. The presence of a magnetic field was able to modify the optical transmittance in the sample and the potentiality to generate structured light was proposed. Numerical simulations were conducted to analyze the magnetic field phenomena and the oscillations of the electric field in the studied sample. We discussed theoretical concepts, experimental methods, and computational tools employed to evaluate the third-order nonlinear optical properties of CNT in film form. Immediate applications of the system to modulate structured light can be contemplated.
ABSTRACT
Introduction: Currently, diabetes mellitus represents one of the medical conditions that more frequently complicates pregnancy affecting the fetus's growth and development. Objective: To determine the skeletal malformations and growth alterations in fetuses of diabetic Wistar rats. Materials and methods: We used a neonatally streptozotocin-induced mild diabetes model (STZ 100 mg/kg body weight - subcutaneously) in Wistar rats. In adulthood, healthy and diabetic rats were mated with healthy males of the same age and strain. On day 20 of gestation, a cesarean was performed under anesthesia. Fetuses were removed, weighed, and classified as small (SPA), adequate (APA), and large (LPA) for the gestational age. Selected fetuses were processed for skeletal anomaly and ossification sites analysis. Results: In the offspring of diabetic rats, there was a higher percentage of fetuses classified as small or large and a lower percentage of fetuses with adequate weight; the fetal weight mean was lower and there were fewer sites of ossification. Alterations were observed in the ossification of the skull, sternum, spine, ribs and fore and hind limbs; and also, there was a direct correlation between fetal weight and ossification degree. There were congenital malformations associated with fusion and bifurcation of the ribs, as well as changes indicative of hydrocephaly, such as the dome shape of the skull, a wide distance between parietals, and the width of the anterior and posterior fontanels. Conclusion: Moderate diabetes during pregnancy alters fetal growth and development with macrosomia and intrauterine growth restriction, as well as skeletal malformations.
Introducción. En la actualidad, la diabetes mellitus representa una de las condiciones médicas que complica el embarazo con mayor frecuencia, lo que afecta el crecimiento y el desarrollo fetal. Objetivo. Determinar las malformaciones esqueléticas y alteraciones en el crecimiento en fetos de ratas Wistar diabéticas. Materiales y métodos. Se utilizó un modelo de diabetes moderada inducida neonatalmente con estreptozotocina (STZ 100 mg/kg de peso corporal, por vía subcutánea) en ratas Wistar. En la adultez, las ratas sanas y diabéticas se aparearon con machos sanos de la misma edad y cepa. El día 20 de gestación se practicó la cesárea bajo anestesia. Se extrajeron los fetos, se pesaron y clasificaron como pequeños (PAG), adecuados (AEG) o grandes (GEG) para la edad gestacional. Los fetos seleccionados se procesaron para el análisis de anomalías esqueléticas y sitios de osificación. Resultados. En la descendencia de las ratas diabéticas, hubo un mayor porcentaje de fetos clasificados como pequeños o grandes y un menor porcentaje de fetos con peso adecuado; el promedio de peso fetal fue menor y había menos sitios de osificación. Se observaron alteraciones en la osificación de cráneo, esternón, columna vertebral, costillas y extremidades anteriores y posteriores; y también, hubo una correlación directa entre el peso y el grado de osificación fetal. Hubo malformaciones congénitas asociadas con la fusión y bifurcación de las costillas, así como cambios indicativos de hidrocefalia, como la forma de domo del cráneo, una amplia distancia entre los parietales y la anchura de las fontanelas anterior y posterior. Conclusión. La diabetes moderada durante la gestación altera el crecimiento y el desarrollo fetal, que se ve afectado tanto por macrosomía y la restricción del crecimiento intrauterino como por malformaciones esqueléticas.
Subject(s)
Diabetes Mellitus, Experimental , Animals , Female , Fetal Growth Retardation , Fetus , Gestational Age , Male , Pregnancy , Rats , Rats, WistarABSTRACT
Resumen Introducción. En la actualidad, la diabetes mellitus representa una de las condiciones médicas que complica el embarazo con mayor frecuencia, lo que afecta el crecimiento y el desarrollo fetal. Objetivo. Determinar las malformaciones esqueléticas y alteraciones en el crecimiento en fetos de ratas Wistar diabéticas. Materiales y métodos. Se utilizó un modelo de diabetes moderada inducida neonatalmente con estreptozotocina (STZ 100 mg/kg de peso corporal, por vía subcutánea) en ratas Wistar. En la adultez, las ratas sanas y diabéticas se aparearon con machos sanos de la misma edad y cepa. El día 20 de gestación se practicó la cesárea bajo anestesia. Se extrajeron los fetos, se pesaron y clasificaron como pequeños (PAG), adecuados (AEG) o grandes (GEG) para la edad gestacional. Los fetos seleccionados se procesaron para el análisis de anomalías esqueléticas y sitios de osificación. Resultados. En la descendencia de las ratas diabéticas, hubo un mayor porcentaje de fetos clasificados como pequeños o grandes y un menor porcentaje de fetos con peso adecuado; el promedio de peso fetal fue menor y había menos sitios de osificación. Se observaron alteraciones en la osificación de cráneo, esternón, columna vertebral, costillas y extremidades anteriores y posteriores; y también, hubo una correlación directa entre el peso y el grado de osificación fetal. Hubo malformaciones congénitas asociadas con la fusión y bifurcación de las costillas, así como cambios indicativos de hidrocefalia, como la forma de domo del cráneo, una amplia distancia entre los parietales y la anchura de las fontanelas anterior y posterior. Conclusión. La diabetes moderada durante la gestación altera el crecimiento y el desarrollo fetal, que se ve afectado tanto por macrosomía y la restricción del crecimiento intrauterino como por malformaciones esqueléticas.
Abstract Introduction: Currently, diabetes mellitus represents one of the medical conditions that more frequently complicates pregnancy affecting the fetus's growth and development. Objective: To determine the skeletal malformations and growth alterations in fetuses of diabetic Wistar rats. Materials and methods: We used a neonatally streptozotocin-induced mild diabetes model (STZ 100 mg/kg body weight - subcutaneously) in Wistar rats. In adulthood, healthy and diabetic rats were mated with healthy males of the same age and strain. On day 20 of gestation, a cesarean was performed under anesthesia. Fetuses were removed, weighed, and classified as small (SPA), adequate (APA), and large (LPA) for the gestational age. Selected fetuses were processed for skeletal anomaly and ossification sites analysis. Results: In the offspring of diabetic rats, there was a higher percentage of fetuses classified as small or large and a lower percentage of fetuses with adequate weight; the fetal weight mean was lower and there were fewer sites of ossification. Alterations were observed in the ossification of the skull, sternum, spine, ribs and fore and hind limbs; and also, there was a direct correlation between fetal weight and ossification degree There were congenital malformations associated with fusion and bifurcation of the ribs, as well as changes indicative of hydrocephaly, such as the dome shape of the skull, a wide distance between parietals, and the width of the anterior and posterior fontanels. Conclusion: Moderate diabetes during pregnancy alters fetal growth and development with macrosomia and intrauterine growth restriction, as well as skeletal malformations.
Subject(s)
Diabetes Mellitus, Experimental , Fetal Growth Retardation , Congenital Abnormalities , Fetal Macrosomia , TeratogenesisABSTRACT
Alendronate, a bisphosphonate used to prevent osteoporosis, stimulates osteogenesis but impairs adipogenesis. Different clinical trials suggest that the incidence of diabetes may be lower in patients treated with alendronate. Taking into account the importance of adipocytes and macrophages of adipose tissue in insulin resistance and type 2 diabetes, it is necessary to evaluate the effect of alendronate in both cell types. In this paper, we investigated the effect of alendronate on the differentiation to adipocytes of 3T3-L1 fibroblasts, the cell line most used to study adipogenesis, and also its effect on lipid content and oxidative stress in mature adipocytes as well as on the inflammatory response of macrophages. We found that alendronate inhibits differentiation of 3T3-L1 fibroblasts to adipocytes in keeping with reports in other cell lines. On the other hand, treatment of 3T3-L1 adipocytes with alendronate was able to decrease triglyceride content and to prevent H2O2-induced lipid peroxidation which was evaluated as an indicator of oxidative stress. In addition, it was found that activation of RAW 264.7 macrophages to a pro-inflammatory M1 type is inhibited by this bisphosphonate. These results suggest that alendronate may contribute to prevent adipocyte excessive enlargement and the induction of oxidative stress in 3T3-L1 adipocytes as well as the activation of macrophages to a pro-inflammatory M1 type, which are events associated with adipose tissue dysfunction and insulin resistance. In this study, we unraveled the underlying mechanisms of events that were previously observed in clinical trials.
Subject(s)
Alendronate , Diabetes Mellitus, Type 2 , 3T3-L1 Cells , Adipocytes , Adipogenesis , Adipose Tissue/metabolism , Alendronate/metabolism , Alendronate/pharmacology , Animals , Cell Differentiation , Diabetes Mellitus, Type 2/metabolism , Humans , Hydrogen Peroxide/metabolism , Macrophages , Mice , Oxidative Stress , Triglycerides/metabolismABSTRACT
Lead (Pb) is an environmental and industrial contaminant that still represents a public health problem. In this paper, we investigated the effect of Pb on proliferation, lipid peroxidation and the number of micronucleated cells in exponentially growing 3T3-L1 fibroblasts, a cell line previously used to evaluate different environmental contaminants. We found that Pb (10 µM or higher) was able to inhibit proliferation of exponentially growing cells after 24-h treatment, which was evaluated by the MTT assay and cell counting in Neubauer chamber, but cell survival was not affected according to the trypan blue exclusion assay. On the other hand, Pb was able to increase lipid peroxidation and the number of micronucleated cells, which are indicative of oxidative stress and genotoxic damage respectively. We also found that removal of Pb after 24-h treatment allowed cells to recover proliferation. Our results indicate that Pb was able to induce oxidative stress and genotoxicity in this cell line under standardized conditions, which supports the involvement of Pb in similar effects observed in human exposed to this heavy metal. In addition, Pb inhibits proliferation of exponentially growing fibroblasts but cells resume proliferation after removal of this metal, which suggests that it is important to move away Pb-exposed individuals from the source of contamination.
ABSTRACT
Research shows that the exclusion of families' funds of knowledge (FoK) from the curriculum contributes to low levels of school engagement. This study is part of an ongoing research project aiming to promote school engagement among students from immigrant backgrounds through the strategic use of FoK. We provide an overview of the project design and explain how it has been implemented in the specific context of early childhood education in a school in Catalonia. A qualitative approach is used to assess the effect of the process from the teacher perspective, contrasting positive aspects with some of the difficulties experienced. We conclude that including families' FoK in pedagogical practice can contribute towards improving student engagement and fostering more inclusive educational environments.
Algumas pesquisas mostram que excluir os fundos de conhecimento (FoK) das famílias do currículo escolar contribui para os baixos níveis de envolvimento na escola. Este estudo é parte de um projeto de pesquisa em andamento que visa promover o envolvimento dos estudantes de origem imigrante na escola, por meio do uso estratégico do FoK. Fornecemos uma visão geral do projeto e explicamos como ele foi implementado no contexto específico da educação infantil em uma escola na Catalunha. Foi utilizada uma abordagem qualitativa para avaliar o efeito do processo pela perspectiva do professor, contrastando aspectos positivos com algumas das dificuldades vivenciadas. Concluímos que a inclusão do FoK das famílias na prática pedagógica pode contribuir para melhorar o envolvimento dos alunos e promover ambientes educacionais mais inclusivos.
Las investigaciones demuestran que la exclusión de los fondos de conocimiento (FoK) de las familias del currículum contribuye a bajos niveles de compromiso escolar. Este estudio forma parte de una investigación en curso destinada a promover el compromiso escolar entre alumnos de origen inmigrante mediante el uso estratégico de FoK. Proporcionamos una descripción general del diseño del proyecto y explicamos cómo se ha implementado en el contexto específico de educación de primera infancia en un centro escolar en Cataluña. Aplicamos una metodología cualitativa para evaluar el efecto del proceso desde la perspectiva del profesorado, contrastando los aspectos positivos con algunas dificultades experimentadas. Concluimos que la inclusión de los FoK de las familias en la práctica pedagógica puede contribuir a mejorar el compro miso escolar y a fomentar un entorno educativo más inclusivo.
ABSTRACT
Expanding the reaction scope of natural metalloenzymes can provide new opportunities for biocatalysis. Mononuclear non-heme iron-dependent enzymes represent a large class of biological catalysts involved in the biosynthesis of natural products and catabolism of xenobiotics, among other processes. Here, we report that several members of this enzyme family, including Rieske dioxygenases as well as α-ketoglutarate-dependent dioxygenases and halogenases, are able to catalyze the intramolecular C-H amination of a sulfonyl azide substrate, thereby exhibiting a promiscuous nitrene transfer reactivity. One of these enzymes, naphthalene dioxygenase (NDO), was further engineered resulting in several active site variants that function as C-H aminases. Furthermore, this enzyme could be applied to execute this non-native transformation on a gram scale in a bioreactor, thus demonstrating its potential for synthetic applications. These studies highlight the functional versatility of non-heme iron-dependent enzymes and pave the way to their further investigation and development as promising biocatalysts for non-native metal-catalyzed transformations.
Subject(s)
Dioxygenases/metabolism , Ferrous Compounds/metabolism , Imines/metabolism , Metalloproteins/metabolism , Amination , Biocatalysis , Dioxygenases/chemistry , Dioxygenases/isolation & purification , Escherichia coli/chemistry , Escherichia coli/cytology , Escherichia coli/metabolism , Ferrous Compounds/chemistry , Ferrous Compounds/isolation & purification , Imines/chemistry , Metalloproteins/chemistry , Metalloproteins/isolation & purification , Models, Molecular , Molecular StructureABSTRACT
O A infecção pelo HIV é uma epidemia multifacetada no Brasil e no mundo. É necessário entender os diferentes aspectos relacionados à distribuição e disseminação do vírus, através do desenho dos vários perfis de pessoas que vivem com HIV/AIDS (PVHA). O estudo apresenta o objetivo de traçar o perfil clínico e sociodemográfico dos pacientes portadores de HIV atendidos ambulatorialmente no Hospital do Servidor Público Municipal, em São Paulo SP Brasil. Trata-se de um estudo descritivo, transversal e retrospectivo que utiliza os dados coletados em questionário e informações registradas em prontuários de atendimento ambulatorial. Foram coletados dados referentes as características sociodemográficas, comportamentais, clínicas e sorológicas de 44 pacientes. A amostra foi composta de 56,8% de homens e 43,2% de mulheres, com média de idade de 53,3 anos a, 45,5% apresentando raça branca autodeclarada e 43,2% referindo parceiro sexual único e fixo. Destes, 52,6% sorodiscordantes. A maior parte dos participantes possui ensino superior completo (36,4%), são heterossexuais (63,6%) e usam preservativos em todas as relações sexuais (59,0%). Foram definidos 19 casos de AIDS de acordo com o critério CDC modificado, representando 43,1% da amostra. A média de contagem de linfóticos T CD4+ na última consulta foi de 602,7 (± 271,5) e 77,2% dos pacientes apresentavam carga viral indetectável. Apenas um caso de coinfecção por tuberculose pulmonar foi descrito. O herpes-Zoster e a candidíase oral foram as doenças relacionadas ao HIV/AIDS mais prevalentes entre os pacientes, enquanto a hipertensão arterial, dislipidemia e depressão foram as comorbidades clínicas mais frequentemente relatas. Ao comparar dados sociodemográficos dos participantes da pesquisa ao perfil nacional e estadual, foi possível concluir que os pacientes atendidos neste serviço apresentavam idade mais avançada e maior nível de escolaridade que a média das demais PVHA. Em sua maioria, os participantes mantiveram um ou nenhum parceiro sexual no último ano, referindo uso constante de preservativos durante as relações sexuais, o que contraria o estigma recaído inicialmente sobre as PVAH. A presença de parcerias sexuais únicas sorodiscordantes em aproximadamente metade dos casos fala a favor do cuidado com a supressão viral e uso de preservativos durante relações sexuais. Palavras-chave: HIV. Síndrome da Imunodeficiência Adquirida. EpidemiologiaO A infecção pelo HIV é uma epidemia multifacetada no Brasil e no mundo. É necessário entender os diferentes aspectos relacionados à distribuição e disseminação do vírus, através do desenho dos vários perfis de pessoas que vivem com HIV/AIDS (PVHA). O estudo apresenta o objetivo de traçar o perfil clínico e sociodemográfico dos pacientes portadores de HIV atendidos ambulatorialmente no Hospital do Servidor Público Municipal, em São Paulo SP Brasil. Trata-se de um estudo descritivo, transversal e retrospectivo que utiliza os dados coletados em questionário e informações registradas em prontuários de atendimento ambulatorial. Foram coletados dados referentes as características sociodemográficas, comportamentais, clínicas e sorológicas de 44 pacientes. A amostra foi composta de 56,8% de homens e 43,2% de mulheres, com média de idade de 53,3 anos a, 45,5% apresentando raça branca autodeclarada e 43,2% referindo parceiro sexual único e fixo. Destes, 52,6% sorodiscordantes. A maior parte dos participantes possui ensino superior completo (36,4%), são heterossexuais (63,6%) e usam preservativos em todas as relações sexuais (59,0%). Foram definidos 19 casos de AIDS de acordo com o critério CDC modificado, representando 43,1% da amostra. A média de contagem de linfóticos T CD4+ na última consulta foi de 602,7 (± 271,5) e 77,2% dos pacientes apresentavam carga viral indetectável. Apenas um caso de coinfecção por tuberculose pulmonar foi descrito. O herpes-Zoster e a candidíase oral foram as doenças relacionadas ao HIV/AIDS mais prevalentes entre os pacientes, enquanto a hipertensão arterial, dislipidemia e depressão foram as comorbidades clínicas mais frequentemente relatas. Ao comparar dados sociodemográficos dos participantes da pesquisa ao perfil nacional e estadual, foi possível concluir que os pacientes atendidos neste serviço apresentavam idade mais avançada e maior nível de escolaridade que a média das demais PVHA. Em sua maioria, os participantes mantiveram um ou nenhum parceiro sexual no último ano, referindo uso constante de preservativos durante as relações sexuais, o que contraria o estigma recaído inicialmente sobre as PVAH. A presença de parcerias sexuais únicas sorodiscordantes em aproximadamente metade dos casos fala a favor do cuidado com a supressão viral e uso de preservativos durante relações sexuais. Palavras-chave: HIV. Síndrome da Imunodeficiência Adquirida. Epidemiologia
Subject(s)
Humans , Male , Female , Epidemiology , Acquired Immunodeficiency SyndromeABSTRACT
We investigated for the first time the expression of melanoma cell adhesion molecule (MCAM) and its involvement in the differentiation of 3T3-L1 fibroblasts to adipocytes. We found that MCAM mRNA increased subsequent to the activation of the master regulator of adipogenesis, PPARγ, and this increase was maintained in the mature adipocytes. On the other hand, MCAM knockdown impaired differentiation and induction of PPARγ as well as expression of genes activated by PPARγ. However, events that precede and are necessary for early PPARγ activation, such as C/EBPß induction, ß-catenin downregulation, and ERK activation, were not affected in the MCAM knockdown cells. In keeping with this, the increase in PPARγ mRNA that precedes MCAM induction was not altered in the knockdown cells. In conclusion, our findings suggest that MCAM is a gene upregulated and involved in maintaining PPARγ induction in the late but not in the early stages of 3T3-L1 fibroblasts adipogenesis.
Subject(s)
Adipocytes/metabolism , Adipogenesis , Cell Differentiation , Fibroblasts/metabolism , Gene Expression Regulation , PPAR gamma/biosynthesis , 3T3-L1 Cells , Adipocytes/cytology , Animals , CD146 Antigen/genetics , CD146 Antigen/metabolism , Fibroblasts/cytology , Gene Knockdown Techniques , Mice , PPAR gamma/geneticsABSTRACT
Lead (Pb) is an environmental and industrial contaminant that still represents a public health problem. Elevated Pb exposure has been inversely correlated with femoral bone density and associated with osteoporosis. In the last years, it has been shown that inhibition of osteogenesis from mesenchymal stem cells activates adipogenesis and vice versa. In this paper, we investigated the effect of Pb on the differentiation of 3T3-L1 fibroblasts to adipocytes which is the cell model most used to study adipogenesis. After induction of differentiation, 2 days post-confluent cells re-enter the cell cycle and undergo mitotic clonal expansion (MCE) followed by expression of genes that produce the adipocyte phenotype. The presence of concentrations of Pb up to 10 µM during differentiation of 3T3-L1 fibroblasts did not interfere with MCE but enhanced the accumulation of cytosolic lipids that occur during adipogenesis, as well as, the induction of PPARγ, the master gene in adipogenesis. It is known that PPARγ upregulation is subsequent to induction of C/EBPß and ERK activation, which are early events in adipogenesis. We found that both events were enhanced by Pb treatment. Our results support a stimulatory effect of Pb on adipogenesis which involves ERK activation and C/EBPß upregulation prior to PPARγ and adipogenesis activation.
Subject(s)
Adipocytes/metabolism , Adipogenesis/drug effects , CCAAT-Enhancer-Binding Protein-beta/metabolism , Fibroblasts/metabolism , Lead/toxicity , MAP Kinase Signaling System/drug effects , PPAR gamma/metabolism , 3T3-L1 Cells , Adipocytes/pathology , Animals , Fibroblasts/pathology , MiceABSTRACT
Glyphosate-based herbicides (GF) are extensively used for weed control. Thus, it is important to investigate their putative toxic effects. We have reported that GF at subagriculture concentrations inhibits proliferation and differentiation to adipocytes of 3T3-L1 fibroblasts. In this investigation, we evaluated the effect of GF on genes upregulated during adipogenesis. GF was able to inhibit the induction of PPAR gamma, the master gene in adipogenesis but not C/EBP beta, which precedes PPAR gamma activation. GF also inhibited differentiation and proliferation of another model of preadipocyte: mouse embryonic fibroblasts. In exponentially growing 3T3-L1 cells, GF increased lipid peroxidation and the activity of the antioxidant enzyme, superoxide dismutase. We also found that proliferation was inhibited with lower concentrations of GF when time of exposure was extended. Thus, GF was able to inhibit proliferation and differentiation of preadipocytes and to induce oxidative stress, which is indicative of its ability to alter cellular physiology.
Subject(s)
Adipocytes/drug effects , Adipogenesis/drug effects , Fibroblasts/drug effects , Glycine/analogs & derivatives , Herbicides/pharmacology , PPAR gamma/genetics , 3T3-L1 Cells , Adipocytes/cytology , Adipocytes/metabolism , Animals , CCAAT-Enhancer-Binding Protein-beta/genetics , CCAAT-Enhancer-Binding Protein-beta/metabolism , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Embryo, Mammalian , Fibroblasts/cytology , Fibroblasts/metabolism , Gene Expression Regulation , Glycine/pharmacology , Lipid Peroxidation/drug effects , Mice , Oxidative Stress , PPAR gamma/antagonists & inhibitors , PPAR gamma/metabolism , Primary Cell Culture , Signal Transduction , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , GlyphosateABSTRACT
Enzymatic dioxygenation of benzyl azide by toluene dioxygenase (TDO) produces significant amounts of the cis-cyclohexadienediol derived from benzonitrile, along with the expected azido diols. We demonstrate that TDO catalyses the oxidation of benzyl azide to benzonitrile, which is further dioxygenated to produce the observed cis-diol. A proposed mechanism for this transformation involves initial benzylic monooxygenation followed by a nitrene-mediated rearrangement to form an oxime, which is further dehydrated to afford the nitrile. To the best of our knowledge, this is the first report of enzymatic oxidation of an alkyl azide to a nitrile. In addition, the described oxime-dehydration activity has not been reported for Rieske dioxygenases.
Subject(s)
Azides/metabolism , Nitriles/metabolism , Oxygenases/metabolism , Pseudomonas putida/enzymology , Azides/chemistry , Benzyl Compounds/chemistry , Benzyl Compounds/metabolism , Models, Molecular , Nitriles/chemistry , Oxidation-Reduction , Oxygenases/chemistry , Pseudomonas putida/chemistry , Pseudomonas putida/metabolismABSTRACT
Enzymatic dioxygenation of benzyl azide by toluene dioxygenase produces the expected enantiopure cis-cyclohexadienediol along with an exocyclic diene formed by a spontaneous sequence of two [3,3] sigmatropic shifts. This novel dienediol presents high synthetic potential for natural product synthesis. The sigmatropic rearrangements can be reversed by protection of the diol moiety. An optimized production protocol for either of these valuable diols is presented.
Subject(s)
Alcohols/chemical synthesis , Azides/chemistry , Oxygenases/metabolism , Alcohols/chemistry , Molecular Structure , StereoisomerismABSTRACT
We aimed to describe and compare the general morphological, somatotype and training background characteristics of Iberian waterpolo players (22 Portuguese and 22 Spanish National Teams players) considering their playing positions. The International Working Group of Kinanthropometry guidelines was herein followed, and a somatochart was obtained through specific software (Somatotype, Calculation and Analysis. (c)2001 SWEAT technologies). Spanish players train more hours per week (22.8 ±9.5 vs.12.2 ±5.6), are taller (187.4 cm ±6.6 vs.180.3 cm ±5.1), heavier (89.2 kg ±11.6 vs.79.1 kg ±10.0), show higher arm span (195.7 cm ±8.5 vs.185.2 cm ±7.4) and muscle mass percentage (49.0% ± 1.8 vs.46.0% ±6.0), and tend to be more mesomorphic (5.19 ±1.27 vs.4.26 ±1.32) than the Portuguese players. Concerning field positions, Spanish center forward players train more hours per week than the Portuguese (20.2 ±9.1 vs.12.2 ±3.8) and show higher arm span (204.4 cm ±7.3 vs.184.0 cm ±6.5). Spanish goal keepers and outside players show higher muscle mass percentage (49.8% ±1.5 vs.42.2% ±5.2 and 49.4% ±1.5 vs.45.5% ±4.6, respectively) than the Portuguese players. These evidences should be taken into account for the improvement of waterpolo sport...
"Comparação de indicadores morfológicos e do tempo de treino semanal em equipes de pólo aquático de diferentes níveis competitivos." O presente estudo objetivou descrever e comparar a morfologia geral, o somatótipo e horas de treino de jogadores Ibéricos de selecções nacionais de polo aquático (22 portugueses e 22 espanhóis) e compará-los quanto às posições de jogo. Utilizou-se um software específico para o desenho da somatocarta (Somatotype, Calculation and Analysis,(c)2001 SWEAT technologies). Os jogadores espanhóis, quando comparados com os portugueses, treinam mais horas por semana (22,8 ±9,5 vs.12,2 ±5,6), são mais altos (187,4 cm ±6,6 vs.180,3 cm ±5,1), mais pesados (89,2 kg ±11,6 vs.79,1 kg ±10,0), apresentam maior envergadura (195,7 cm ±8,5 vs. 185,2 cm ±7,4), percentagem de massa muscular (49,0% ±1,8 vs. 46,0% ±6,0) e tendem a ser mais mesomorfos (5,19 ±1,27 vs. 4,26 ±1,32) do que os jogadores portugueses. Quanto às posições de jogo, os pivôs espanhóis treinam mais horas por semana (20,2 ±9,1 vs.12,2 ±3,8) e apresentam maior envergadura (204,4 cm ±7,3 vs.184,0 cm ±6,5) que os portugueses. Ainda, respectivamente, os goleiros e os jogadores laterais espanhóis apresentam percentagens mais elevadas de massa muscular (49,8% ±1,5 vs.42,2% ±5,2 e 49,4% ±1,5 vs.45,5% ±4,6) do que os portugueses. Estas evidências devem ser consideradas para a melhoria do polo aquático...
"Comparación de indicadores morfológicos y de tiempo de entrenamiento semanal en equipos de waterpolo de diferentes niveles competitivos" El objetivo del estudio fue describir y comparar la morfología general, somatotipo y horas de entrenamiento de jugadores Ibéricos de selecciones nacionales de waterpolo (22 portugueses y 22 españoles) y comparar sus diferencias entre posiciones de juego. Los parámetros evaluados fueron seleccionados en la literatura. La somatocarta fue construida con un software específico (Somatotype, Calculation and Analysis, (c)2001 SWEAT technologies). Los jugadores españoles entrenan más horas por semana (22,8 ±9,5 vs.12,2 ±5,6), tienen más altura (187,4cm ± 6,6 vs.180,3 cm ±5.1), más peso (89,2 kg ±11,6 vs.79,1 kg ±10,0), más envergadura (195,7 cm ±8,5 vs. 185,2 cm ±7,4), porcentaje de masa muscular (49,0% ±1,8 vs. 46,0% ±6,0) y tienden a presentar valores más altos de mesomorfia (5,19 ±1,27 vs. 4,26 ±1,32) que los jugadores portugueses. Con respecto a las posiciones de juego, los boyas Españoles superan los portugueses en las horas de entrenamiento semanal (20,2 ±9,1 vs.12,2 ±3,8) y presentan más envergadura (204,4 cm ±7,3 vs.184,0 cm ±6,5). Los porteros y jugadores periféricos españoles tienen más masa muscular que los jugadores portugueses (49,8% ±1,5 vs. 42,2% ±5,2 e 49,4% ±1,5 vs.45,5% ±4,6), respectivamente. Estas evidencias deberán ser consideradas para la mejora del waterpolo...
Subject(s)
Humans , Male , Adult , Athletic Performance , /methods , SportsABSTRACT
Heavy metals contamination has become an important risk factor for public health and the environment. Chromium is a frequent industrial contaminant and is also used in orthopaedic joint replacements made from cobalt-chromium-alloy. Since hexavalent chromium (Cr(VI)) was reported as genotoxic and carcinogenic in different mammals, to further evaluate its cytotoxicity, we investigated the effect of this heavy metal in the proliferation and differentiation to adipocytes of 3T3-L1 fibroblasts. These cells, after the addition of a mixture containing insulin, dexamethasone and methylisobutylxanthine, first proliferate, a process known as mitotic clonal expansion (MCE), and then differentiate to adipocytes. In this differentiation process a key transcription factor is induced: peroxisome proliferator-activated receptor gamma (PPAR gamma). We found that treatment of 3T3-L1 fibroblasts with potassium chromate inhibited proliferation in exponentially growing cells and MCE as well as differentiation. A decrease in PPAR gamma content, evaluated by western blot and immunofluorescence, was found in cells differentiated in the presence of chromium. On the other hand, after inhibition of differentiation with chromium, when the metal was removed, differentiation was recovered, which indicates that this may be a reversible effect. We also found an increase in the number of micronucleated cells after treatment with Cr(VI) which is associated with genotoxic effects. According to our results, Cr(VI) is able to inhibit proliferation and differentiation to adipocytes of 3T3-L1 fibroblasts and to increase micronucleated cells, which are all indicative of alterations in cellular physiology and therefore, contributes to further elucidate the cytotoxic effects of this heavy metal.
Subject(s)
Adipocytes/cytology , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Chromium/toxicity , Fibroblasts/drug effects , 3T3-L1 Cells , Adipocytes/drug effects , Animals , Environmental Pollutants/toxicity , Fibroblasts/cytology , Fibroblasts/physiology , MiceABSTRACT
Adipogenesis is stimulated in 3T3-L1 fibroblasts by a combination of insulin, dexamethasone and isobutylmethylxanthine, IBMX, (I+D+M). Two transcription factors are important for the acquisition of the adipocyte phenotype, C/EBP beta (CCAT enhancer-binding protein beta) and PPAR gamma (peroxisome proliferator-activated receptor gamma). IBMX increases cAMP content, which can activate protein kinase A (PKA) and/or EPAC (exchange protein activated by cAMP). To investigate the importance of IBMX in the differentiation mixture, we first evaluated the effect of the addition of IBMX on the increase of C/EBP beta and PPAR gamma and found an enhancement of the amount of both proteins. IBMX addition (I+D+M) or its replacement with a cAMP analogue, dibutyryl-cAMP or 8-(4-chlorophenylthio)-2-O'-methyl-cAMP (8CPT-2-Me-cAMP), the latter activates EPAC and not PKA, remarkably increased PPAR gamma mRNA. However, neither I+D nor any of the inducers alone, increased PPAR gamma mRNA to a similar extent, suggesting the importance of the presence of both IBMX and I+D. It was also found that the addition of IBMX or 8CPT-2-Me-cAMP was able to increase the content of C/EBP beta with respect to I+D. In agreement with these findings, a microarray analysis showed that the presence of either 8CPT-2-Me-cAMP or IBMX in the differentiation mixture was able to upregulate PPAR gamma and PPAR gamma-activated genes as well as other genes involved in lipid metabolism. Our results prove the involvement of IBMX-cAMP-EPAC in the regulation of adipogenic genes during differentiation of 3T3-L1 fibroblasts and therfore contributes to elucidate the role of cyclic AMP in this process.
Subject(s)
Adipogenesis/genetics , Cell Differentiation/physiology , Cyclic AMP/metabolism , Gene Expression Regulation/physiology , Guanine Nucleotide Exchange Factors/metabolism , 1-Methyl-3-isobutylxanthine/metabolism , 3T3-L1 Cells , Adipogenesis/physiology , Analysis of Variance , Animals , Azo Compounds , Blotting, Western , CCAAT-Enhancer-Binding Protein-beta/metabolism , Cell Count , DNA Primers/genetics , Dexamethasone/metabolism , Insulin/metabolism , Mice , Microarray Analysis , Microscopy, Fluorescence , PPAR gamma/metabolismABSTRACT
Normal fear is defined as a reaction to a real or imagined threat and is considered an integral and adaptive feature related to the primary function of survival. Nevertheless, when fear is intense and maladaptive, it may lose its role for survival and may progress in a phobic disorder with a negative impact for the individual who suffers it. According to some researchers, childhood and adolescence are the main life periods where phobias and other anxiety disorders develop. It is estimated that up to 50% of children and adolescents report one or more intense fears and more than 20% of these meet diagnostic criteria for specific phobias, frequently related to the development of future mental disorders during adulthood. In the assessment of fear, it is important to consider the evaluation of its intensity as well as its frequency among three main dimensions: the subjective dimension (including feelings and thoughts), the physical dimension (e.g., tachycardia and paleness) and the behavioral dimension (e.g., avoidant behaviors). So far, the main fear assessment methods include self-reports, observation and psychophysiological registers. In the area of mental health, the Fear Survey Schedule for Children II (FSSC-II) is the most widely used instrument for the assessment of fears in youth population. The cultural adaptation of an internationally instrument such as the FSSC-II brings the opportunity for subsequent comparison of investigation findings with other populations. The FSSC-II is an updated version of the original instrument as it includes other type of fears such as fear of war and/or AIDS designed to both children and adolescents. Since it is possible that some mental disorders in adulthood are conditioned by the presence of fears in early stages of life, it is important to have an objective characterization of the main fears in our culture. On this basis, adequate psychopathology prevention programs and treatment strategies can be designed and tested. In general, psychopathology is influenced by the cultural context and fears are not the exception as they tend to manifest differently from one cultural context to another. Therefore, the aim of the present work was to translate, culturally adapt and examine the psychometric properties of the FSSC-II in a Mexican sample of high school students. Method A total of 5030 high school students who accepted to participate in the study were recruited. Age ranged between 14 and 24 years old. The FSSC-II is composed of 78 items scored in a three-point Likert scale that assess frequency and intensity of different fears classified in five main dimensions: fear of death and danger, fear of the unknown, fear of failure or criticism, fear of animals and physical stress-medical fears. Before the enrollment procedure, the FSSC-II was adapted for Mexican population. First, translation-back translation was performed by two independent translators. Some items of the instrument were culturally adapted by consensus to reach the final version of the instrument. A principal component analysis with varimax rotation was performed to determine the construct validity of the instrument in Mexican population. Cronbach's alpha was used to determine the internal consistency of each domain and total score of the FSSC-II. All analyses were performed with the 10th version of the SPSS-X. Results A total of 2992 women and 2038 men participated. Mean age was of 16.43±1.2 years old. For the Mexican adaptation of the FSSC-II, 1 1.53% of the items (n=18) were culturally adapted. Factor analysis showed five factors for the instrument. These factors were consistent with those described in the original version: fear of death and danger, fear of animals or injuries, fear of failure or criticism, fear of the unknown and medical fears. Internal consistency of the FSSC-II was .96. Alpha coefficients for four dimensions were above .80, except the "medical fears" dimension (.70). Discussion The Spanish version of the FSSC-II among Mexican high school students showed adequate psychometric properties. The adaptation process implicated the modification of some items of the original instruments in order to reach a correct assessment of the proposed constructs of the instrument according to the predominant cultural patterns of Mexico. On the other hand, some items were not modified and were taken literally from either U.S. or Australian versions. Although more than 10% of the items were adjusted, the factor structure of the instrument remained congruent with the original version and the U.S version of the FSSC-II. The Mexican version was totally compatible with the five constructs found in the U.S. version; nevertheless it is important to remark that the content of the Mexican version was more compatible with the content of the items of the Australian version. Some of the inconsistencies found between the three versions may be the result of the subjects' age in the studies. The U.S. study included subjects with ages between 8 and 11 years, the Australian study included subjects between 7 and 18 years old, while our study included subjects with ages between 14 and 24 years old. The way children experience reality is not the same as that of adolescents or adults. It is possible to assume that the fears of children are more related to immediate, concrete stimuli, while the ones of adolescents and young adults are related to anticipatory or abstract stimuli. For example, the item of "Fear of being scolded by the principal" can be experienced by a child as something extremely dangerous and, therefore, the item will classify in the dimension "fear of death and danger" and not in the dimension of "fear of failure or criticism" where the answer of an adolescent or a young adult is most likely to be classified. Despite the disparities between the three versions, the FSSC-II showed high internal consistency values and an adequate percentage of explained variance in our sample. These results highlight the utility of the FSSC-II for the assessment of the frequency and intensity of fears in both adolescents and young adults in Mexico. It would be desirable to perform future studies among children.
El miedo es una emoción que se experimenta a lo largo de la vida y en ocasiones posibilita la adaptación. No obstante, el miedo puede tornarse desadaptativo y evolucionar hacia un trastorno fóbico que impacta negativamente en el individuo que lo padece. La infancia y la adolescencia son las etapas en las que típicamente inician las fobias, las cuales se han asociado al desarrollo de otros trastornos mentales en la vida adulta. En la evaluación del miedo es necesario evaluar tanto su intensidad como su frecuencia en tres dimensiones principales: la subjetiva, la física y la conductual. Los principales métodos de valoración del miedo han sido los autoinformes, la observación externa y los registros psicofisiológicos. En el área de la salud mental, la escala más utilizada para la evaluación de miedos en población juvenil es el Inventario de Miedos para Niños II (Fear Survey Schedule for Children II, FSSC-II). La adaptación cultural de un instrumento internacionalmente utilizado como éste brinda la oportunidad de realizar comparaciones subsecuentes de los hallazgos de investigación con otras poblaciones. Dado el impacto del miedo en el futuro desarrollo de trastornos mentales, es importante contar con una caracterización de los principales miedos en nuestra población para la elaboración de futuros programas preventivos y de tratamiento efectivos. De esta forma, el objetivo del presente estudio fue traducir al español, adaptar culturalmente y evaluar psicométricamente el Inventario de Miedos para Niños FSSC-II en una muestra de adolescentes y adultos jóvenes mexicanos. Método La muestra estuvo conformada por estudiantes de preparatoria de ambos sexos, entre 14 y 24 años de edad, que aceptaron participar en el estudio de manera anónima. Dos traductores independientes realizaron la traducción-retraducción y adaptación cultural del FSSC-II y posteriormente fue aplicado a los estudiantes. Se obtuvo la consistencia interna del instrumento mediante el alpha de Cronbach y la validez de constructo mediante un análisis de componentes principales. Resultados Se incluyeron 2992 mujeres y 2038 hombres, con una edad promedio de 16.43 años. El 11.53% de los reactivos de la versión original del FSSC-II se adaptaron para su uso en población mexicana. El análisis factorial mostró cinco factores agrupados de acuerdo con lo teóricamente esperado: miedo a la muerte o peligro, miedo a los animales o lesiones, miedo al fracaso escolar o a la crítica, miedo a lo desconocido y miedos médicos. Todos los factores del FSSC-II mostraron elevados valores de consistencia interna (>.80) con excepción del área de miedos médicos (.70). El alpha de la puntuación total de la escala fue de .96. Discusión La estructura de cinco factores del instrumento resultó congruente con la versión australiana original y la estadounidense, siendo compatible en su totalidad con la versión de Estados Unidos. No obstante, en cuanto al contenido de los reactivos, la versión mexicana del FSSC-II fue más similar a la versión australiana del instrumento. Estas inconsistencias pueden deberse a las diferencias de edades de las muestras sujetas a estudio, siendo distintas las realidades que vive un niño a las que vive un adolescente o un adulto joven. A pesar de estas divergencias, la alta consistencia interna y varianza explicada del instrumento muestran su utilidad para evaluar la frecuencia e intensidad de miedos en adolescentes y adultos jóvenes en nuestro país. Es deseable dirigir futuros estudios para evaluar a niños de menores edades.