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1.
Appl Microbiol Biotechnol ; 105(21-22): 8019-8032, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34655320

RESUMO

Nitroalkanes such as nitromethane, nitroethane, 1-nitropropane (1NP), and 2-nitropropane (2NP), derived from anthropogenic activities, are hazardous environmental pollutants due to their toxicity and carcinogenic activity. In nature, 3-nitropropionate (3NPA) and its derivatives are produced as a defense mechanism by many groups of organisms, including bacteria, fungi, insects, and plants. 3NPA is highly toxic as its conjugate base, propionate-3-nitronate (P3N), is a potent inhibitor of mitochondrial succinate dehydrogenase, essential to the tricarboxylic acid cycle, and can inhibit isocitrate lyase, a critical enzyme of the glyoxylate cycle. In response to these toxic compounds, several organisms on the phylogenetic scale express genes that code for enzymes involved in the catabolism of nitroalkanes: nitroalkane oxidases (NAOs) and nitronate monooxygenases (NMOs) (previously classified as nitropropane dioxygenases, NPDs). Two types of NMOs have been identified: class I and class II, which differ in structure, catalytic efficiency, and preferred substrates. This review focuses on the biochemical properties, structure, classification, and physiological functions of NMOs, and offers perspectives for their in vivo and in vitro applications. KEY POINTS: • Nitronate monooxygenases (NMOs) are key enzymes in nitroalkane catabolism. • NMO enzymes are involved in defense mechanisms in different organisms. • NMO applications include organic synthesis, biocatalysts, and bioremediation.


Assuntos
Alcanos , Oxigenases de Função Mista , Oxigenases de Função Mista/genética , Filogenia
2.
FASEB J ; 33(7): 8363-8374, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30964711

RESUMO

Cellular checkpoints controlling entry into mitosis monitor the integrity of the DNA and delay mitosis onset until the alteration is fully repaired. However, this canonical response can weaken, leading to a spontaneous bypass of the checkpoint, a process referred to as checkpoint adaptation. Here, we have investigated the contribution of microcephalin 1 (MCPH1), mutated in primary microcephaly, to the decatenation checkpoint, a less-understood G2 pathway that delays entry into mitosis until chromosomes are properly disentangled. Our results demonstrate that, although MCPH1 function is dispensable for activation and maintenance of the decatenation checkpoint, it is required for the adaptive response that bypasses the topoisomerase II inhibition----mediated G2 arrest. MCPH1, however, does not confer adaptation to the G2 arrest triggered by the ataxia telangiectasia mutated- and ataxia telangiectasia and rad3 related-based DNA damage checkpoint. In addition to revealing a new role for MCPH1 in cell cycle control, our study provides new insights into the genetic requirements that allow cellular adaptation to G2 checkpoints, a process that remains poorly understood.-Arroyo, M., Kuriyama, R., Guerrero, I., Keifenheim, D., Cañuelo, A., Calahorra, J., Sánchez, A., Clarke, D. J., Marchal, J. A. MCPH1 is essential for cellular adaptation to the G2-phase decatenation checkpoint.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas do Citoesqueleto/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular Transformada , Proteínas do Citoesqueleto/genética , Humanos
3.
Appl Microbiol Biotechnol ; 104(7): 2987-2997, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060694

RESUMO

Metarhizium species are the most abundant fungi that can be isolated from soil, with a well-known biopesticide capacity. Metarhizium recognizes their hosts when the conidium interacts with insects, where the fungi are in contact with the hydrocarbons of the outermost lipid layer cuticle. These cuticular hydrocarbons comprise a mixture of n-alkanes, n-alkenes, and methyl-branched chains. Metarhizium can degrade insect hydrocarbons and use these hydrocarbons for energy production and the biosynthesis of cellular components. The metabolism of nitroalkanes involves nitronate monooxygenase activity. In this work, we isolated a family of six genes with potential nitronate monooxygenase activity from Metarhizium brunneum. The six genes were expressed in Escherichia coli, and the nitronate monooxygenase activity was verified in the recombinant proteins. Additionally, when the conidia of M. brunneum were grown in medium with nitroalkanes, virulence against Plutella xylostella increased. Furthermore, we analyzed the expression of the six Npd genes during the infection to this insect, which showed differential expression of the six Npd genes during infection.


Assuntos
Agentes de Controle Biológico/metabolismo , Dioxigenases/metabolismo , Metarhizium/enzimologia , Mariposas/microbiologia , Alcanos/metabolismo , Animais , DNA Fúngico/genética , Dioxigenases/genética , Hidrocarbonetos/metabolismo , Proteínas de Insetos/metabolismo , Metarhizium/genética , Metarhizium/patogenicidade , Controle Biológico de Vetores , Virulência/genética
4.
Int J Mol Sci ; 20(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547237

RESUMO

Upon tumor antigen recognition, cytotoxic T lymphocytes (CTLs) and target cells form specialized supramolecular structures, called cytotoxic immunological synapses, which are required for polarized delivery of cytotoxic granules. In previous reports, we described the accumulation of connexin 43 (Cx43)-formed gap junctions (GJs) at natural killer (NK) cell-tumor cell cytotoxic immunological synapse. In this report, we demonstrate the functional role of Cx43-GJs at the cytotoxic immunological synapse established between CTLs and melanoma cells during cytotoxicity. Using confocal microscopy, we evaluated Cx43 polarization to the contact site between CTLs isolated from pMEL-1 mice and B16F10 melanoma cells. We knocked down Cx43 expression in B16F10 cells and evaluated its role in the formation of functional GJs and the cytotoxic activity of CTLs, by calcein transfer and granzyme B activity assays, respectively. We found that Cx43 localizes at CTL/B16F10 intercellular contact sites via an antigen-dependent process. We also found that pMEL-1 CTLs but not wild-type naïve CD8+ T cells established functional GJs with B16F10 cells. Interestingly, we observed that Cx43-GJs were required for an efficient granzyme B activity in target B16F10 cells. Using an HLA-A2-restricted/MART-1-specific CD8+ T-cell clone, we confirmed these observations in human cells. Our results suggest that Cx43-channels are relevant components of cytotoxic immunological synapses and potentiate CTL-mediated tumor cell killing.


Assuntos
Conexina 43/imunologia , Junções Comunicantes/imunologia , Sinapses Imunológicas/imunologia , Melanoma/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Junções Comunicantes/patologia , Humanos , Sinapses Imunológicas/patologia , Melanoma/patologia , Camundongos Endogâmicos C57BL , Linfócitos T Citotóxicos/patologia
5.
J Ind Microbiol Biotechnol ; 44(1): 63-74, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27853904

RESUMO

Fermentative processes are widely used to produce food, beverages and biofuels. Saccharomyces cerevisiae is an efficient ethanol-producing microorganism. However, a concentration of high ethanol and other metabolites can affect yeast viability and decrease the ethanol yield. Many studies have focused on improving the fermentative efficiency, mostly through the genetic engineering of genes that have a direct impact on specific metabolic pathways. In the present study, we characterized a small open reading frame encoding a protein with an unknown function and biological role termed YNR034W-A. We analyzed the expression profile of the YNR034W-A gene during growth and glucose treatment, finding that it is expressed during the diauxic shift and stationary phase and is negatively regulated by glucose. We overexpressed the YNR034W-A gene in the BY4741 laboratory strain and a wild-type yeast strain (AR5) isolated during the Tequila fermentation process. Transformant derivatives of the AR5 strain showed an improved fermentative efficiency during fermentation of Agave tequilana Weber juice. We suggest that the improved fermentative efficiency is the result of a higher stress tolerance response in the YNR034W-A overexpressing transformant.


Assuntos
Agave , Fermentação , Fases de Leitura Aberta , Saccharomyces cerevisiae/genética , Bebidas Alcoólicas/análise , Etanol/metabolismo , Perfilação da Expressão Gênica , Engenharia Genética , Glucose/química , Microbiologia Industrial , Saccharomyces cerevisiae/metabolismo
6.
Catheter Cardiovasc Interv ; 88(6): 971-977, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27511120

RESUMO

OBJECTIVE: The objective of this study was to evaluate safety, efficacy, and durability of coil embolization of the major septal perforator of the left anterior descending coronary artery in patients with hypertrophic obstructive cardiomyopathy (HOCM). BACKGROUND: The long-term effect of coil embolization therapy in HOCM patients is not well defined. METHODS: We evaluated 24 symptomatic HOCM patients in a single center who underwent coil embolization of the septal perforator artery(ies). RESULTS: Twenty-four patients on optimal medical therapy presented with NYHA functional class III (75%) or IV (25%) underwent the procedure. The procedure was successful in 22 patients, with significant reduction in left ventricular outflow tract (LVOT) gradient. The functional class significantly improved to class I (54.2%) or II (41.7%) (P < = 0.01). The LVOT gradient was significantly lower during follow up echocardiography (21.3 ± 19 vs. 81.3 ± 41 mm Hg; P < = 0.01). Interventricular septal thickness decreased over time (16.3 ± 3 vs. 18.5 ± 2 mm, P< = 0.01). The procedure was aborted in one of the patients after the third coil prolapsed from the septal perforator in to the left anterior descending artery. The coil was effectively snared out. Three patients required additional coil placement in the second major septal perforator. New permanent pacemaker placement was required in one patient. However, three patients underwent ICD implantation at follow up due to ventricular arrhythmias. CONCLUSIONS: The results of this study suggest that the use of coil embolization for septal ablation is safe, effective, and durable in patients with symptomatic HOCM. © 2016 Wiley Periodicals, Inc.


Assuntos
Cardiomiopatia Hipertrófica/cirurgia , Ablação por Cateter/métodos , Vasos Coronários/cirurgia , Embolização Terapêutica/instrumentação , Septos Cardíacos/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cardiomiopatia Hipertrófica/diagnóstico , Vasos Coronários/diagnóstico por imagem , Ecocardiografia , Desenho de Equipamento , Feminino , Septos Cardíacos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
7.
J Immunol ; 192(3): 1313-9, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24376266

RESUMO

Gap junctions (GJs) mediate intercellular communication between adjacent cells. Previously, we showed that connexin 43 (Cx43), the main GJ protein in the immune system, mediates Ag transfer between human dendritic cells (DCs) and is recruited to the immunological synapse during T cell priming. This crosstalk contributed to T cell activation, intracellular Ca(2+) responses, and cytokine release. However, the role of GJs in NK cell activation by DCs and NK cell-mediated cytotoxicity against tumor cells remains unknown. In this study, we found polarization of Cx43 at the NK/DC and NK/tumor cell-contact sites, accompanied by the formation of functional GJs between NK/DCs and NK/tumor cells, respectively. Cx43-GJ-mediated intercellular communication (GJIC) between human NK and DCs was bidirectional. Blockage of Cx43-GJIC inhibited NK cell activation, though it affected neither the phenotype nor the function of DCs. Cx43 knockdown or inhibition using mimetic peptides greatly reduced CD69 and CD25 expression and IFN-γ release by DC-stimulated NK cells. Moreover, blocking Cx43 strongly inhibited the NK cell-mediated tumor cell lysis associated with inhibition of granzyme B activity and Ca(2+) influx. Our data identify a novel and active role for Cx43-GJIC in human NK cell activation and antitumor effector functions that may be important for the design of new immune therapeutic strategies.


Assuntos
Conexina 43/imunologia , Citotoxicidade Imunológica/imunologia , Células Dendríticas/imunologia , Junções Comunicantes/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária/imunologia , Apoptose , Sinalização do Cálcio , Comunicação Celular/imunologia , Linhagem Celular Tumoral , Conexina 43/antagonistas & inibidores , Células Dendríticas/ultraestrutura , Granzimas/fisiologia , Humanos , Vigilância Imunológica , Sinapses Imunológicas/imunologia , Testes de Liberação de Interferon-gama , Células Matadoras Naturais/ultraestrutura
8.
J Fungi (Basel) ; 9(9)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37755053

RESUMO

Beneficial associations are very important for plants and soil-dwelling microorganisms in different ecological niches, where communication by chemical signals is relevant. Among the chemical signals, the release of phytohormones by plants is important to establish beneficial associations with fungi, and a recently described association is that of the entomopathogenic ascomycete fungus Metarhizium with plants. Here, we evaluated the effect of four different phytohormones, synthetic strigolactone (GR24), sorgolactone (SorL), 3-indolacetic acid (IAA) and gibberellic acid (GA3), on the fungus Metarhizium guizhouense strain HA11-2, where the germination rate and hyphal elongation were determined at three different times. All phytohormones had a positive effect on germination, with GA3 showing the greatest effect, and for hyphal length, on average, the group treated with synthetic strigolactone GR24 showed greater average hyphal length at 10 h of induction. This work expands the knowledge of the effect of phytohormones on the fungus M. guizhouense, as possible chemical signals for the rapid establishment of the fungus-plant association.

9.
Cells ; 12(18)2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37759461

RESUMO

Fungal alcohol dehydrogenases (ADHs) participate in growth under aerobic or anaerobic conditions, morphogenetic processes, and pathogenesis of diverse fungal genera. These processes are associated with metabolic operation routes related to alcohol, aldehyde, and acid production. The number of ADH enzymes, their metabolic roles, and their functions vary within fungal species. The most studied ADHs are associated with ethanol metabolism, either as fermentative enzymes involved in the production of this alcohol or as oxidative enzymes necessary for the use of ethanol as a carbon source; other enzymes participate in survival under microaerobic conditions. The fast generation of data using genome sequencing provides an excellent opportunity to determine a correlation between the number of ADHs and fungal lifestyle. Therefore, this review aims to summarize the latest knowledge about the importance of ADH enzymes in the physiology and metabolism of fungal cells, as well as their structure, regulation, evolutionary relationships, and biotechnological potential.


Assuntos
Cirurgia Bariátrica , Etanol , Aldeídos , Evolução Biológica , Oxirredutases
10.
Microbiology (Reading) ; 157(Pt 1): 199-208, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20929953

RESUMO

Insect pathogenic fungi such as Metarhizium anisopliae and Beauveria bassiana have an increasing role in the control of agricultural insect pests and vectors of human diseases. Many of the virulence factors are well studied but less is known of the metabolism of these fungi during the course of insect infection or saprobic growth. Here, we assessed enzyme activity and gene expression in the central carbon metabolic pathway, including isocitrate dehydrogenase, aconitase, citrate synthase, malate synthase (MLS) and isocitrate lyase (ICL), with particular attention to the glyoxylate cycle when M. anisopliae and B. bassiana were grown under various conditions. We observed that ICL and MLS, glyoxylate cycle intermediates, were upregulated during growth on 2-carbon compounds (acetate and ethanol) as well as in insect haemolymph. We fused the promoter of the M. anisopliae ICL gene (Ma-icl) to a marker gene (mCherry) and showed that Ma-icl was upregulated when M. anisopliae was grown in the presence of acetate. Furthermore, Ma-icl was upregulated when fungi were engulfed by insect haemocytes as well as during appressorium formation. Addition of the ICL inhibitor 3-nitroproprionate delayed conidial germination and inhibited appressorium formation. These results show that these insect pathogenic fungi have a flexible metabolism that includes the glyoxylate cycle as an integral part of germination, pathogenesis and saprobic growth.


Assuntos
Beauveria/metabolismo , Glioxilatos/metabolismo , Insetos/microbiologia , Metarhizium/metabolismo , Animais , Fusão Gênica Artificial , Meios de Cultura/química , Perfilação da Expressão Gênica , Genes Reporter , Hemolinfa/microbiologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Redes e Vias Metabólicas/genética
11.
Appl Microbiol Biotechnol ; 87(3): 1033-44, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20361327

RESUMO

Catalases and peroxidases are the most important enzymes that degrade hydrogen peroxide into water and oxygen. These enzymes and superoxide dismutase are the first lines of cell defense against reactive oxygen species. Metarhizium anisopliae displays an increase in catalase-peroxidase activity during germination and growth. To determine the importance of catalase during the invasion process of M. anisopliae, we isolated the cat1 gene. cat1 cDNA expression in Escherichia coli and the subsequent purification of the protein confirmed that the cat1 gene codes for a monofunctional catalase. Expression analysis of this gene by RT-PCR from RNA isolated from fungus grown in liquid cultures showed a decrease in the expression level of the cat1 gene during germination and an increase during mycelium growth. The expression of this gene in the fungus during the infection process of the larvae of Plutella xylostella also showed a significant increase during invasive growth. Transgenic strains overexpressing the cat1 gene had twice the catalase activity of the wild-type strain. This increase in catalase activity was accompanied by a higher level of resistance to exogenous hydrogen peroxide and a reduction in the germination time. This improvement was also observed during the infection of P. xylostella larvae. M. anisopliae transgenic strains overexpressing the cat1 gene grew and spread faster in the soft tissue of the insect, reducing the time to death of the insect by 25% and the dose required to kill 50% of the population 14-fold.


Assuntos
Catalase/genética , Proteínas Fúngicas/genética , Expressão Gênica , Metarhizium/enzimologia , Metarhizium/patogenicidade , Esporos Fúngicos/crescimento & desenvolvimento , Animais , Catalase/metabolismo , Proteínas Fúngicas/metabolismo , Metarhizium/genética , Metarhizium/crescimento & desenvolvimento , Mariposas/microbiologia , Micélio/enzimologia , Micélio/genética , Micélio/crescimento & desenvolvimento , Micélio/patogenicidade , Esporos Fúngicos/enzimologia , Esporos Fúngicos/genética , Esporos Fúngicos/patogenicidade
12.
Curr Protein Pept Sci ; 21(3): 324-330, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951168

RESUMO

The fungal genus Metarhizium has been used as an entomopathogen worldwide for approximately 140 years, and its mechanism of infection and its virulence factors have been studied. The present review is a compilation of virulence factors described in the literature to date and their participation in specific stages of the infection process.


Assuntos
Proteínas Fúngicas/genética , Metarhizium/genética , Micoses/genética , Fatores de Virulência/genética , Metarhizium/patogenicidade , Micoses/microbiologia
13.
Med. crít. (Col. Mex. Med. Crít.) ; 37(2): 99-105, Feb. 2023. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1558396

RESUMO

Resumen: Introducción: la neumonía por coronavirus es emergente. Existen pocos datos del manejo ventilatorio. Presenta diferentes fenotipos pulmonares con difícil programación de la ventilación mecánica (VM). Se analizan estos pacientes en un hospital general. Material y métodos: se incluyen pacientes con neumonía por SARS-CoV-2 que ingresan a la unidad de cuidados intensivos (UCI) ventilados entre marzo y junio de 2020. Analizamos demografía, gravedad, programación ventilatoria, gases arteriales, mecánica pulmonar y desenlaces. Se describen los pacientes que recibieron posición prona (PP). Los pacientes se categorizaron por mediana de la compliance estática (Cst) y rangos ≤ 20, > 20 a ≤ 30 y > 30 en el día uno. Resultados: 118 pacientes, edad promedio 56.4 ± 1.3, 76.4% varones. El APACHE II y SOFA de ingreso: 13.6 ± 0.5 y 8.3 ± 0.2. Requirieron PP 47.5%. Los días de VM, UCI y hospital fueron 13.5 ± 0.9; 16.8 ± 0.9 y 23.8 ± 1.5. La mortalidad hospitalaria de pacientes PP y supinos fue de 32.1 y 11.3%, p = 0.005. Mortalidad global de 21.2%. Pacientes con Cst ≤ 20 mL/cmH2O presentaron una mortalidad de 44.4%. Conclusión: un porcentaje importante de los pacientes requiere PP precoz para superar la hipoxemia y aunque la mayoría responden, no asegura un buen desenlace hospitalario. Los pacientes con Cst ≤ 20 ml/cmH2O muestran mayor mortalidad.


Abstract: Introduction: coronavirus infection is an emerging pathology, there are few data regarding ventilatory management. Different pulmonary phenotypes make the MV process difficult. This encouraged us to analyze our COVID-19 patients with MV. Material and methods: all patients with SARS-CoV-2 pneumonia who were admitted ventilated to our unit through March to June 2020 were included. Demographics, severity scores, ventilatory settings, arterial gases, lung mechanics, and outcomes are analyzed. The patients who received prone position (PP) are described. Patients were categorized according to the median static compliance (Cst) and if it was ≤ 20, > 20 a ≤ 30 y > 30 in day 1. Results: 118 patients, the mean age was 56.4 ± 1.3, 76.4% males. APACHE II and SOFA on admission: 13.6 ± 0.5 and 8.3 ± 0.2. 47.5% of the patients required PP. The MV, ICU and hospital stay were 13.5 ± 0.9; 16.8 ± 0.9 and 23.8 ± 1.5 days. The in-hospital mortality of PP and supine patients was 32.1 and 11.3%, p = 0.005. Overall mortality 21.2%. Mortality of patients with Cst ≤ 20 mL/cmH2O was 44.4%. Conclusion: a significant percentage require early PP to overcome hypoxemia and although most respond, it does not ensure a good hospital outcome. The patients with compliance ≤ 20ml/ cmH2O have higher mortality.


Resumo: Introdução: a pneumonia por coronavírus é emergente. Existem poucos dados sobre o manejo ventilatório. Apresenta diferentes fenótipos pulmonares com difícil programação da VM. Esses pacientes são analisados em um hospital geral. Material e métodos: incluíram-se pacientes com pneumonia por SARS-CoV-2 internados na UTI ventilados entre março e junho de 2020. Analisamos dados demográficos, gravidade, programação ventilatória, gasometria arterial, mecânica pulmonar e desfechos. São descritos os pacientes que receberam posição prona (PP). Os pacientes foram categorizados pela média da compliance estática (Cst) e intervalos ≤ 20, >20 a ≤ 30 e >30 em 1 dia. Resultados: 118 pacientes, idade média 56.4 ± 1.3, 76.4% do sexo masculino. O APACHE II e SOFA de admissão: 13.6 ± 0.5 e 8.3 ± 0.2. Necessitaram PP 47.5%. Os dias de VM, UTI e hospital foram 13.5 ± 0.9; 16.8 ± 0.9 e 23.8 ± 1.5. A mortalidade hospitalar dos pacientes em PP e supino foi de 32.1 e 11.3%, p = 0.005. Mortalidade geral 21.2%. Pacientes com Cst ≤ 20 mL/cmH2O apresentaram mortalidade de 44.4%. Conclusão: muitos pacientes requerem PP precoce para superar a hipoxemia. A média da compliance não discrimina a mortalidade. Aqueles com Cst ≤ 20 apresentam maior mortalidade.

14.
Insects ; 9(3)2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30126092

RESUMO

Different strains of Metarhizium exhibit a range of polymorphisms in colony phenotypes. These phenotypes range from highly conidiating colonies to colonies that produce relatively more mycelia and few conidia. These different phenotypes are exhibited in infected insects in the soil. In this paper, we provide a theoretical consideration of colony polymorphisms and suggest that these phenotypes represent a range of strategies in the soil that Metarhizium exhibits. We call these different strategies "sleepers" and "creepers". The "sleeper" phenotype produces relatively greater amounts of conidia. We use the term "sleeper" to identify this phenotype since this strategy is to remain in the soil as conidia in a relatively metabolically inactive state until a host insect or plant encounter these conidia. The "creeper" phenotype is predominantly a mycelial phenotype. In this strategy, hyphae move through the soil until a host insect or plant is encountered. We theoretically model the costs and benefits of these phenotypic polymorphisms and suggest how evolution could possibly select for these different strategies.

15.
Mycobiology ; 45(2): 84-89, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28781540

RESUMO

Fungi of the Metarhizium genus are a very versatile model for understanding pathogenicity in insects and their symbiotic relationship with plants. To establish a co-transformation system for the transformation of multiple M. robertsii genes using Agrobacterium tumefaciens, we evaluated whether the antibiotic nourseothricin has the same marker selection efficiency as phosphinothricin using separate vectors. Subsequently, in the two vectors containing the nourseothricin and phosphinothricin resistance cassettes were inserted eGFP and mCherry expression cassettes, respectively. These new vectors were then introduced independently into A. tumefaciens and used to transform M. robertsii either in independent events or in one single co-transformation event using an equimolar mixture of A. tumefaciens cultures. The number of transformants obtained by co-transformation was similar to that obtained by the individual transformation events. This method provides an additional strategy for the simultaneous insertion of multiple genes into M. robertsii.

16.
J Agric Food Chem ; 65(43): 9435-9442, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28942644

RESUMO

Guineensine is a dietary N-isobutylamide widely present in black and long pepper (Piper nigrum and Piper longum) previously shown to inhibit cellular endocannabinoid uptake. Given the role of endocannabinoids in inflammation and pain reduction, here we evaluated guineensine in mouse models of acute and inflammatory pain and endotoxemia. Significant dose-dependent anti-inflammatory effects (95.6 ± 3.1% inhibition of inflammatory pain at 2.5 mg/kg ip and 50.0 ± 15.9% inhibition of edema formation at 5 mg/kg ip) and acute analgesia (66.1 ± 28.1% inhibition at 5.0 mg/kg ip) were observed. Moreover, guineensine inhibited proinflammatory cytokine production in endotoxemia. Intriguingly, guineensine and LPS independently induced catalepsy, but in combination this effect was abolished. Both hypothermia and analgesia were blocked by the CB1 receptor inverse agonist rimonabant, but the pronounced hypolocomotion was CB1 receptor-independent. A subsequent screen of 45 CNS-related receptors, ion channels, and transporters revealed apparent interactions of guineensine with the dopamine transporter DAT, 5HT2A, and sigma receptors, uncovering its prospective polypharmacology. The described potent pharmacological effects of guineensine might relate to the reported anti-inflammatory effects of pepper.


Assuntos
Alcenos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Edema/tratamento farmacológico , Endocanabinoides/metabolismo , Compostos Heterocíclicos com 2 Anéis/administração & dosagem , Inflamação/tratamento farmacológico , Piper nigrum/química , Extratos Vegetais/administração & dosagem , Animais , Edema/metabolismo , Endocanabinoides/antagonistas & inibidores , Humanos , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Sementes/química
17.
J Nucl Cardiol ; 13(4): 507-13, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16919574

RESUMO

BACKGROUND: Coronary artery disease is frequent in postmenopausal women. Silent myocardial ischemia has been induced with mental stress testing. METHODS AND RESULTS: To evaluate whether mental stress can induce ischemia in women with typical angina and normal coronary angiography, postmenopausal patients (n = 16) were studied. Each underwent technetium 99m methoxyisobutylisonitrile myocardial scintigraphy (exercise stress/rest/mental stress protocol), brachial artery endothelial function measurement by ultrasonography, and 24-hour ambulatory electrocardiographic recording (Holter). During mental stress testing, 6 patients (group I) had reversible perfusion defects on myocardial scintigraphy whereas the other 10 patients (group II) did not. Group I patients exhibited endothelial dysfunction more frequently than those in group II (83% vs 20%). Myocardial scintigraphy showed anteroapical/septal ischemia in 5 patients and inferoapical ischemia in one other patient, with both types of stress. Among group II patients, none showed a reversible perfusion defect during physical or mental stress. No group I patients had evidence of ischemia by Holter monitoring, whereas 2 of 10 group II patients did. CONCLUSION: In postmenopausal women with typical angina and normal coronary arteries, mental stress may provoke myocardial ischemia, which can be concordant with ischemia induced by exercise stress, and is associated with endothelial dysfunction.


Assuntos
Angina Pectoris/diagnóstico por imagem , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Estresse Psicológico/complicações , Angina Pectoris/etiologia , Angiografia Coronária , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Pessoa de Meia-Idade , Cintilografia , Medição de Risco/métodos , Fatores de Risco , Saúde da Mulher
18.
Microbiol Res ; 172: 57-67, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25534970

RESUMO

Zymography of alcohol dehydrogenase (ADH) activity in the entomopathogenic fungus Metarhizium anisopliae grown under various conditions revealed that micro-aerobic growth was associated with increased ADH activity. The major ADH protein, AdhIp, was purified to homogeneity by affinity chromatography and has an estimated molecular weight of 41kDa and an isoelectric point (pI) of 6.4. Peptide mass fingerprint analysis allowed the identification and cloning of the gene that encodes this protein, Adh1, as annotated in the M. anisopliae genome database. AdhIp is related to the medium-chain dehydrogenase/reductase (MDR)/zinc-dependent alcohol dehydrogenase-like family and contains conserved ADH sequence motifs, such as the zinc-containing ADH signature, the FAD/NAD binding domain and amino acid residues that are conserved in most microbial ADHs. Semi-quantitative RT-PCR analysis revealed that Adh1 gene expression occurs at low levels during early Plutella xylostella infection and that the Adh1 gene was primarily expressed at larval death and as mycelia emerge from the insect cuticle before conidiation. Antisense-RNA experiments indicated that NAD(+)-dependent ADH activity was diminished by 20-75% in the transformants, and the transformants that had lower ADH activity showed allyl alcohol resistance, which indicates that reduction in ADH activity also occurs in vivo. Bioassays performed using antisense adh1 transformants, which have lower ADH activity, showed that LC50 values were two to five times higher than the wild-type, indicating that AdhIp is required for full capability of the fungus to penetrate and/or colonize the insect.


Assuntos
Álcool Desidrogenase/metabolismo , Lepidópteros/microbiologia , Metarhizium/enzimologia , Metarhizium/crescimento & desenvolvimento , Álcool Desidrogenase/química , Álcool Desidrogenase/genética , Álcool Desidrogenase/isolamento & purificação , Animais , Clonagem Molecular , Perfilação da Expressão Gênica , Inativação Gênica , Ponto Isoelétrico , Larva/microbiologia , Larva/fisiologia , Lepidópteros/fisiologia , Metarhizium/genética , Peso Molecular , Reação em Cadeia da Polimerase em Tempo Real , Homologia de Sequência de Aminoácidos , Análise de Sobrevida , Virulência
19.
J Pharm Pharm Sci ; 7(3): 372-7, 2004 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-15576019

RESUMO

PURPOSE: Fibrinolytic therapy restores coronary patency and reduces mortality in patients with acute myocardial infarction. Albumin is present in most of the streptokinase formulation as a stabilizer but it is not known whether it plays a role in the product's efficacy and safety profiles. The aim of this study was to assess 90 minutes-coronary patency of a new albumin-free recombinant streptokinase (rSK) formulation. METHODS . Patients with ischemic chest pain and ST-segment elevation, less than 12 hours after symptoms onset, without contraindications for fibrinolytic therapy, were included to receive 1.5 x 10(6) IU of rSK in a one-hour intravenous infusion. Angiography was performed 90 minutes after and coronary patency was classified according to the TIMI flow scales. RESULTS: The study enrolled 25 patients, 59.4 +/- 9.2 years-old, 88% men and 92% white. The mean time interval between the symptoms onset and rSK infusion was 3.0 +/- 2.0 hours. Patency rate (TIMI 2-3) of the infarct-related vessel was 72% (18/25). Partial or complete ST-segment resolution was achieved in 17 patients (68%). Hypotension and nauseas were the most frequent adverse events. Haemorrhage or in-hospital deaths were not reported. CONCLUSIONS: This study suggests that intravenous albumin-free rSK is a safe and appropriate therapy to get early (90-minute) coronary patency in patients with acute myocardial infarction.


Assuntos
Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/uso terapêutico , Doença Aguda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estreptoquinase/efeitos adversos , Terapia Trombolítica , Resultado do Tratamento , Grau de Desobstrução Vascular/efeitos dos fármacos
20.
Commun Integr Biol ; 6(1): e22321, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23802036

RESUMO

Most land plants are able to form symbiotic associations with fungi, and in many cases these associations are necessary for plant and fungal survival. These plant/fungal associations are formed with mycorrhizal (arbuscular mycorrhizal or ectomycorrhizal) or endophytic fungi, fungi from distinct phylogenetic lineages. While it has been shown that mycorrhizal fungi are able to transfer nutrients to plant roots in exchange for carbon, endophytes have been thought as asymptomatic colonizers. Recently, however, it has been shown that some insect pathogenic endophytic fungi are able to transfer insect derived nitrogen to plant roots, likely in exchange for plant sugars. Here we explore potential convergent evolutionary strategies for nutrient transfer between insect pathogenic endophytes and mycorrhizal fungus.

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