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1.
J Microbiol ; 61(12): 1043-1062, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38114662

RESUMO

Mucormycosis is a lethal and difficult-to-treat fungal infection caused by fungi of the order Mucorales. Mucor lusitanicus, a member of Mucorales, is commonly used as a model to understand disease pathogenesis. However, transcriptional control of hyphal growth and virulence in Mucorales is poorly understood. This study aimed to investigate the role of Tec proteins, which belong to the TEA/ATTS transcription factor family, in the hyphal development and virulence of M. lusitanicus. Unlike in the genome of Ascomycetes and Basidiomycetes, which have a single Tec homologue, in the genome of Mucorales, two Tec homologues, Tec1 and Tec2, were found, except in that of Phycomyces blakesleeanus, with only one Tec homologue. tec1 and tec2 overexpression in M. lusitanicus increased mycelial growth, mitochondrial content and activity, expression of the rhizoferrin synthetase-encoding gene rfs, and virulence in nematodes and wax moth larvae but decreased cAMP levels and protein kinase A (PKA) activity. Furthermore, tec1- and tec2-overexpressing strains required adequate mitochondrial metabolism to promote the virulent phenotype. The heterotrimeric G beta subunit 1-encoding gene deletant strain (Δgpb1) increased cAMP-PKA activity, downregulation of both tec genes, decreased both virulence and hyphal development, but tec1 and tec2 overexpression restored these defects. Overexpression of allele-mutated variants of Tec1(S332A) and Tec2(S168A) in the putative phosphorylation sites for PKA increased both virulence and hyphal growth of Δgpb1. These findings suggest that Tec homologues promote mycelial development and virulence by enhancing mitochondrial metabolism and rhizoferrin accumulation, providing new information for the rational control of the virulent phenotype of M. lusitanicus.


Assuntos
Mucor , Fatores de Transcrição , Fatores de Transcrição/genética , Virulência/genética , Estresse Oxidativo , Proteínas Fúngicas/genética
2.
Environ Sci Pollut Res Int ; 30(48): 105793-105807, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37721669

RESUMO

This paper aims to analyze the link between environmental degradation and institutional quality and the price of oil moderated by economic complexity and the underground economy. We use quantile regressions with annual panel data for 15 countries in the Middle East and North Africa during 1995-2021. The findings indicate that institutional quality, economic complexity, and output positively and heterogeneously impact environmental degradation. However, the square of production has a negative impact, confirming an inverted U relationship between production and environmental degradation. Likewise, we find that the price of oil and the underground economy have a negative and heterogeneous impact on environmental degradation. Based on our results, a potential recommendation for policymakers is that the institutional framework of Middle Eastern and North African countries should be accompanied by a more significant concern for the environment instead of prioritizing extractive growth that is detrimental to the environment's environmental sustainability. Likewise, economic diversification will mitigate environmental degradation and improve formal employment. Our findings are relevant to policymakers and researchers interested in promoting ecological sustainability.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Dióxido de Carbono/análise , África do Norte , Oriente Médio
3.
Environ Sci Pollut Res Int ; 30(32): 79171-79193, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37284957

RESUMO

Manufacturing is one of the primary sources of environmental pollution due to the emission of polluting gases and waste generation. This research aims to examine the manufacturing industry's effect on an environmental pollution index in nineteen Latin American countries using non-linear methods. The youth population, globalization, property rights, civil liberties, the unemployment gap, and government stability moderate the relationship between the two variables. The research has a temporal coverage between 1990 and 2017 and uses threshold regressions to verify the hypotheses. In order to obtain more specific inferences, we group countries according to the trade block and geographic region to which they belong. Our findings indicate that manufacturing has limited explanatory power for environmental pollution. This finding is supported by the fact that the manufacturing industry in the region is scarce. In addition, we find a threshold effect on the youth population, globalization, property rights, civil liberties, and government stability. Consequently, our results highlight the importance of institutional factors in designing and applying environmental mitigation mechanisms in developing regions.


Assuntos
Comércio , Poluição Ambiental , Adolescente , Humanos , América Latina/epidemiologia
4.
Bioorg Med Chem Lett ; 86: 129241, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36933671

RESUMO

Metformin is the most widely known anti-hyperglycemic, officially acquired by the USA government in 1995 and in 2001 it became the most prescribed treatment for type II diabetes. But how did it become the must-use drug for this disease in such a short period of time? it all started with traditional medicine, by using a plant known as "goat's rue" for the reduction of blood glucose levels. Its use arose in 1918 and evolved to the metformin synthesis in laboratories a couple of years later, using very rudimentary methods which involved melting and strong heating. Thus, a first synthetic route that allowed the preparation of the initial metformin derivates was established. Some of these resulted toxics, and others outperformed the metformin, reducing the blood glucose levels in such efficient way. Nevertheless, the risk and documented cases of lactic acidosis increased with metformin derivatives like buformin and phenformin. Recently, metformin has been widely studied, and it has been associated and tested in the treatment of type II diabetes, cancer, polycystic ovarian syndrome, cell differentiation to oligodendrocytes, reduction of oxidative stress in cells, weight reduction, as anti-inflammatory and even in the recent COVID-19 disease. Herein we briefly review and analyze the history, synthesis, and biological applications of metformin and its derivates.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Metformina , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Glicemia
5.
Can J Microbiol ; 69(5): 185-198, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36753728

RESUMO

Dimorphic species of Mucor, which are cosmopolitan fungi belonging to subphylum Mucoromycotina, are metabolically versatile. Some species of Mucor are sources of biotechnological products, such as biodiesel from Mucor circinelloides and expression of heterologous proteins from Mucor lusitanicus. Furthermore, Mucor lusitanicus has been described as a model for understanding mucormycosis infections. However, little is known regarding the relationship between Mucor lusitanicus and other soil inhabitants. In this study, we investigated the potential use of Mucor lusitanicus as a biocontrol agent against fungal phytopathogens, namely Fusarium oxysporum f. sp. lycopersici, Fusarium solani, and Alternaria solani, which destroy economically important crops. Results showed that aerobic cell-free supernatants of the culture broth (SS) from Mucor lusitanicus inhibited the growth of the fungal phytopathogens in culture, soil, and tomato fruits. The SS obtained from a strain of Mucor lusitanicus carrying the deletion of rfs gene, which encodes an enzyme involved in the synthesis of siderophore rhizoferrin, had a decreased inhibitory effect against the growth of the phytopathogens. Contrarily, this inhibitory effect was more evident with the SS from an rfs-overexpressing strain compared to the wild-type. This study provides a framework for the potential biotechnological use of the molecules secreted from Mucor lusitanicus in the biocontrol of fungal phytopathogens.


Assuntos
Mucor , Mucormicose , Mucor/genética , Sideróforos , Mucormicose/microbiologia , Doenças das Plantas
6.
Sci Rep ; 12(1): 10649, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739200

RESUMO

Mucormycosis is a fungal infection caused by Mucorales, with a high mortality rate. However, only a few virulence factors have been described in these organisms. This study showed that deletion of rfs, which encodes the enzyme for the biosynthesis of rhizoferrin, a siderophore, in Mucor lusitanicus, led to a lower virulence in diabetic mice and nematodes. Upregulation of rfs correlated with the increased toxicity of the cell-free supernatants of the culture broth (SS) obtained under growing conditions that favor oxidative metabolism, such as low glucose levels or the presence of H2O2 in the culture, suggesting that oxidative metabolism enhances virulence through rhizoferrin production. Meanwhile, growing M. lusitanicus in the presence of potassium cyanide, N-acetylcysteine, a higher concentration of glucose, or exogenous cAMP, or the deletion of the gene encoding the regulatory subunit of PKA (pkaR1), correlated with a decrease in the toxicity of SS, downregulation of rfs, and reduction in rhizoferrin production. These observations indicate the involvement of the cAMP-PKA pathway in the regulation of rhizoferrin production and virulence in M. lusitanicus. Moreover, rfs upregulation was observed upon macrophage interaction or during infection with spores in mice, suggesting a pivotal role of rfs in M. lusitanicus infection.


Assuntos
Diabetes Mellitus Experimental , Mucor , Animais , Compostos Férricos , Glucose , Peróxido de Hidrogênio , Camundongos , Mucor/genética , Sideróforos , Virulência/genética
7.
Org Biomol Chem ; 20(25): 5009-5034, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35703407

RESUMO

Iodine(III) reagents have attracted chemical relvance in organic synthesis by their use as safe, non-toxic, green and easy to handle reagents in different transformations. These characteristics make them important alternatives to procedures involving hazardous and harsh reaction conditions. Their versatility as oxidants has been exploited in the functionalization of different aromatic cores, which allow the introduction of several groups. Metal-free arylation using iodine(III) reagents is by far one of the most described topics in the literature; however, other highly relevant non-aromatic groups have been also introduced. Herein, we summarize the most representative developed procedures for the functionalization of aryls and heteroaryls by introducing halogens, using different iodine(III) reagents.


Assuntos
Iodo , Halogenação , Indicadores e Reagentes , Iodetos , Oxirredução , Estresse Oxidativo
8.
Environ Sci Pollut Res Int ; 29(44): 66605-66621, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35508853

RESUMO

Latin America experiences an increasing urban primacy index and a rapid expansion of the financial system, putting direct pressure on the demand for resources to satisfy the consumption of large cities. We investigate the convergence of per capita biocapacity in 16 Latin America countries and evaluate the factors that influence its evolution over time. Specifically, we analyze the impact of the urban primacy index, economic progress, and the financial globalization index on the convergence of per capita biocapacity. We use the methodological framework developed by Phillips and Sul Econometrica 75:1771-1855, (2007) to analyze the convergence and the formation of convergence clubs of biocapacity during 1970-2017. The findings indicate that the countries of the region do not share a common trend of biocapacity, although they are grouped into five converging clubs. Biocapacity transition analysis reveals that countries have heterogeneous transition pathways between them. Using marginal effects, we find that the urban primacy index and economic progress reduce the biocapacity. The effect of the financial globalization index on biocapacity is not conclusive. The quantile regressions reveal that quantiles' impact of the urban primacy index and financial globalization on per capita biocapacity is heterogeneous. However, the effect of economic progress on biocapacity that predominates among quantiles is positive. The adoption of common policies among the countries that form the converging clubs could improve the effectiveness of pro-environmental policies and promote the achievement of the Sustainable Development Goals related to environmental quality.


Assuntos
Desenvolvimento Sustentável , América Latina
9.
ACS Omega ; 7(8): 6944-6955, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35252686

RESUMO

The first gold(I)-catalyzed cycloisomerization procedure applied to the synthesis of substituted 4H-benzo[d][1,3]oxazines has been developed starting from N-(2-alkynyl)aryl benzamides. The chemoselective oxygen cyclization via the 6-exo-dig pathway yielded the observed heterocycles in modest to good chemical yields under very mild reaction conditions. The obtained oxazines were assayed on the breast cancer (BC)-derived cell lines MCF-7 and HCC1954 with differential biological activity. The newly synthesized 4H-benzo[d][1,3]oxazine compounds showed several degrees of cell proliferation inhibition with a remarkable effect for those compounds having a substituted aryl at C-2 of the molecules. The 4H-benzo[d][1,3]oxazines showed an IC50 ranking from 3.1 to 95 µM in MCF-7 and HCC1954 cells. These compounds represent potential drug candidates for BC treatment. However, additional assays are needed to elucidate their complete effect over the cellular and molecular hallmarks of cancer.

10.
Bioorg Med Chem Lett ; 63: 128649, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35245665

RESUMO

Zygomycetes are ubiquitous saprophytes in natural environments which transform organic matter. Some zygomycetes of gender Mucor have attracted interest in health sector. Due to its ability as opportunistic microorganisms infecting immuno-compromised people and to the few available pharmacological treatments, the mucormycosis is receiving worldwide attention. Concerning to the pharmacological treatments, some triazole-based compounds such as fluconazole are extensively used. Nevertheless, we focused in the quinolines since they are broadly used models for the design and development of new synthetic antifungal agents. In this study, the fungistatic activity on M. circinelloides of various 2-aryl-4-aryloxyquinoline-based compounds was discovered, and in some cases, it resulted better than reference compound fluconazole. These quinoline derivatives were synthesized via the Csp2-O bond formation using diaryliodonium(III) salts chemistry. A QSAR study was carried out to quantitatively correlate the chemical structure of the tested compounds with their biological activity. Also, a docking study to identify a plausible action target of our more active quinolines was carried out. The results highlighted an increased activity with the fluorine- and nitro-containing derivatives. In light of the few mucormycosis pharmacological treatments, herein we present some non-described molecules with excellent in vitro activities and potential use in the mucormycosis treatment.


Assuntos
Mucormicose , Quinolinas , Fluconazol , Humanos , Mucor , Mucormicose/tratamento farmacológico , Mucormicose/microbiologia , Relação Quantitativa Estrutura-Atividade , Quinolinas/farmacologia , Quinolinas/uso terapêutico
11.
Environ Sci Pollut Res Int ; 29(12): 16939-16958, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34655033

RESUMO

The energy sector of Argentina is predominantly reliant on fossil fuels. Consequently, such fossil fuel dependency within the nation's power sector, in particular, has aggravated the environmental quality in Argentina by amplifying the nation's energy production-based carbon emission levels. However, keeping into consideration the international commitments pledged by Argentina under the Paris Accord and the Sustainable Development Goals agenda, it is pertinent for this South American country to curb its energy production-based emission of greenhouse gases, especially carbon dioxide. Against this milieu, this study examines the impacts of renewable electricity generation, economic globalization, economic growth, and urbanization on carbon dioxide emissions generated from the production of electricity and heat in the context of Argentina. Using annual frequency data from 1971 to 2016, recent econometric methods are applied to control for multiple structural breaks in the data. The major findings from the ecnometric analyses affirmed long-run associations between renewable electricity generation, economic globalization, economic growth, urbanization, and energy production-based carbon dioxide emissions in Argentina. Besides, enhancing renewable electricity output shares is found to curb these emissions while economic globalization and urbanization are witnessed to boost them. Moreover, renewable electricity generation and economic globalization are found to jointly reduce the energy production-related carbon dioxide emissions in Argentina. The results also validate the authenticity of the Environmental Kuznets Curve (EKC) hypothesis. Finally, the causality analysis reveals evidence of unidirectional causalities running from renewable electricity generation, economic globalization, economic growth, and urbanization to energy production-related carbon dioxide emissions in Argentina. In line with these findings, this study recommends several viable policies which can be implemented to help Argentina control the growth of its energy production-based carbon dioxide emissions.


Assuntos
Dióxido de Carbono , Energia Renovável , Argentina , Dióxido de Carbono/análise , Desenvolvimento Econômico , Internacionalidade
12.
Environ Sci Pollut Res Int ; 28(42): 59771-59783, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34146332

RESUMO

The ecological footprint is an indicator used in recent years to assess the accelerated process of environmental degradation experienced by countries. In particular, in regions or countries with high biodiversity, strong dependence on natural resources, high informality, and low productive specialization. We employ a set of quantitative techniques within the theoretical framework of convergence and found the existence of per capita ecological footprint clubs. In addition, we estimate a set of logistic regressions to obtain the average marginal effect of the determinants of the convergence clubs. We found that economic complexity, the shadow economy, and natural resources significantly influence the formation of convergence clubs. The results indicate the existence of convergence in three clubs, while two clubs are divergent. Environmental policymakers in this region should collectively mitigate environmental degradation and achieve sustainable development goals, particularly among the countries that make up the convergence clubs.


Assuntos
Desenvolvimento Econômico , Recursos Naturais , Conservação dos Recursos Naturais , América Latina , Desenvolvimento Sustentável
13.
J Food Prot ; 84(5): 760-766, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33290541

RESUMO

ABSTRACT: This study investigated the presence of nontuberculous mycobacteria (NTM) for the first time in two types of unpasteurized fresh cheese produced in the state of Michoacan, Mexico. We tested for this pathogen, along with the others, to broaden the study of microbiological quality in 60 samples of cheese, 30 fresh and 30 Adobera, which were collected from six artisanal cheese factories (ACFs). The hygienic conditions of these establishments and the practices of cheese manufacture were generally poor. Although Mycobacterium bovis was not detected, four cheese samples harbored NTM isolates. The four NTM isolates were identified using three molecular markers (hsp65, rrs, and rpoB genes) that corresponded to Mycolicibacterium fortuitum (n = 3) and Mycolicibacterium mageritense (n = 1). All 60 cheese samples analyzed had unsatisfactory microbiological quality according to the Mexican Official Guideline. Regarding fresh cheeses, all 30 samples analyzed were positive for aerobic mesophilic bacteria, total coliforms, fecal coliforms, and yeasts and molds. Escherichia coli and Staphylococcus aureus were present in 23 and 21 samples, respectively. Listeria monocytogenes was identified in a sample and was isolated from a bulk milk tank in the same ACF. With regard to Adobera cheeses, all samples were positive for aerobic mesophilic bacteria, total coliforms, fecal coliforms, yeasts and molds, and S. aureus. E. coli was isolated from 28 samples. Salmonella was isolated from a sample and from a wooden shovel used in the manufacture of the cheeses in the same ACF. Thus, the consumption of unpasteurized fresh cheese may represent a public health risk. Because of this, health authorities should enforce the legislation that forbids the processing of cheese with unpasteurized milk and encourage producers to follow good manufacturing practices from original ingredients, through the production process of the cheese, to its sale to assure a safe product.


Assuntos
Queijo , Listeria monocytogenes , Animais , Queijo/análise , Escherichia coli , Microbiologia de Alimentos , México , Leite , Mycobacteriaceae , Micobactérias não Tuberculosas , Salmonella , Staphylococcus aureus
14.
Front Chem ; 8: 563470, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195052

RESUMO

The chemoselective reaction of the C- followed by the O-centered naphthyl radicals with the more electron-deficient hypervalent bond of the diaryliodonium(III) salts is described. This discovered reactivity constitutes a new activation mode of the diaryliodonium(III) salts which enabled a one-pot doubly arylation of naphthols through the sequential C s p 2 - C s p 2 /O- C s p 2 bond formation. The naphthyl radicals were generated in the reaction by the tetramethylpiperidinyl radical (TMP·) which resulted from the homolytic fragmentation of the precursor TMP2O. Experimental and DFT calculations provided a complete panorama of the reaction mechanism.

15.
Cell Microbiol ; 22(10): e13236, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32562333

RESUMO

Mucor circinelloides, a dimorphic opportunistic pathogen, expresses three heterotrimeric G-protein beta subunits (Gpb1, Gpb2 and Gpb3). The Gpb1-encoding gene is up-regulated during mycelial growth compared with that in the spore or yeast stage. gpb1 deletion mutation analysis revealed its relevance for an adequate development during the dimorphic transition and for hyphal growth under low oxygen concentrations. Infection assays in mice indicated a phenotype with considerably reduced virulence and tissue invasiveness in the deletion mutants (Δgpb1) and decreased host inflammatory response. This finding could be attributed to the reduced filamentous growth in animal tissues compared with that of the wild-type strain. Mutation in a regulatory subunit of cAMP-dependent protein kinase A (PKA) subunit (PkaR1) resulted in similar phenotypes to Δgpb1. The defects exhibited by the Δgpb1 strain were genetically suppressed by pkaR1 overexpression, indicating that the PKA pathway is controlled by Gpb1 in M. circinelloides. Moreover, during growth under low oxygen levels, cAMP levels were much higher in the Δgpb1 than in the wild-type strain, but similar to those in the ΔpkaR1 strain. These findings reveal that M. circinelloides possesses a signal transduction pathway through which the Gpb1 heterotrimeric G subunit and PkaR1 control mycelial growth in response to low oxygen levels.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Fúngicas/metabolismo , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Mucor/crescimento & desenvolvimento , AMP Cíclico/metabolismo , Proteínas Fúngicas/genética , Subunidades beta da Proteína de Ligação ao GTP/genética , Genes Fúngicos , Hifas/crescimento & desenvolvimento , Mucor/metabolismo , Mucor/patogenicidade , Mutação , Micélio/crescimento & desenvolvimento , Oxigênio/análise , Transdução de Sinais , Virulência/genética
16.
Environ Sci Pollut Res Int ; 27(13): 14477-14491, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31953767

RESUMO

Most of the countries of South America depend heavily on mining and agriculture, which develops through the destruction of the forest. The expansion of the agricultural frontier is more visible in countries with proximity to the Amazon. Otherwise, the increase in urban primacy and real income per capita has led to an increase in the use of non-renewable energy in recent decades. The interest in quantifying greenhouse gas emissions has increased, oriented towards the search for mechanisms that mitigate the irreversible effects of climate change. In this context, the objective of this research is to examine the causal link among non-renewable energy consumption and real GDP per capita in greenhouse gas emissions in ten countries of South America during 1971-2014. In addition, we group the countries according to their productive structure and we incorporate the structural changes of each country in the econometric estimations, allowing to significantly improve the understanding of the sources of greenhouse gases. We use cointegration and causality techniques for time series data, and we found that there is a relationship of short- and long-term equilibrium between the three variables in all countries. The causality test indicates that in Bolivia, Peru, and Uruguay, there is causality from the consumption of non-renewable energy to greenhouse gas emissions. Likewise, in Venezuela and the agricultural countries, GDP causes greenhouse gas emissions. An implication of the public policy derived from this research is that most of the countries of South America can promote a change in the energy matrix to contribute to the mitigation of greenhouse gas emissions without limiting economic growth.


Assuntos
Gases de Efeito Estufa , Bolívia , Dióxido de Carbono/análise , Desenvolvimento Econômico , Peru , Energia Renovável , América do Sul
17.
Environ Sci Pollut Res Int ; 27(3): 2760-2772, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31836982

RESUMO

The accelerated urbanization process generates a significant increase in energy, whose sources are mainly polluting. The harmful effects of both processes are reflected in climate change. This article examines the equilibrium and causality relationship among urban concentration, non-renewable energy consumption, and the real per capita output in 110 countries during 1971-2017. Using data from the World Bank's World Development Indicators (2018), we classify countries into four groups according to their level of development. Our evidence suggests that urban concentration has a negative effect on real per capita output in high-income countries, while non-renewable energy consumption has a positive effect on all groups of countries. The cointegration tests show that there is short- and long-term equilibrium in all groups of countries. The results of the DOLS and PDOLS models indicate that the strength of the cointegration vector is weak in most of the countries and groups analyzed. The Granger-type causality tests show that there is bidirectional causality from the real per capita output to the urban concentration in high and middle-low-income countries. There is unidirectional causality from the population concentration towards the real per capita output in the low-income countries; from the non-renewable energy consumption to the real per capita output in high-income countries; from the real per capita output to the non-renewable energy consumption in the countries of medium-high and medium-low income; and from urban concentration to non-renewable energy consumption in high- and medium-high-income countries. Our results highlight the importance of promoting policies of urban planning and generation and consumption of renewable energy without limiting the expansion of the output.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Fontes Geradoras de Energia/estatística & dados numéricos , Cidades/estatística & dados numéricos , Renda , Energia Renovável , Urbanização
18.
Microb Pathog ; 137: 103737, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31513895

RESUMO

Mucor circinelloides is an opportunistic human pathogen that is used to study mucormycosis, a rare but lethal infection in susceptible immunosuppressed patients. However, the virulence characteristics of this pathogen have not been fully elucidated. In this study, sporangiospores (spores) produced on YPG medium supplemented with native blood serum increased the virulence of M. circinelloides compared with spores produced on YPG supplemented with denatured blood serum or on YPG alone. The spores produced from YPG supplemented with native blood serum increased nematode death and led to significant increases in interleukin (IL)-6, IL-1ß, macrophage inhibitory protein-2, and tumour necrosis factor α mRNA levels in liver and lung tissues from infected diabetic mice compared with those in tissues from animals infected with spores produced in the presence of YPG supplemented with denatured blood serum or of YPG alone. Moreover, spores produced from cultures supplemented with native blood serum showed increased germination rates and longer hyphae compared with other spores. The spores produced in YPG supplemented with native blood serum also enhanced resistance to stress factors and H2O2 and increased thermotolerance compared with spores produced under other conditions. In addition, spores produced in presence of blood serum increased the ability of the pathogen to survive in the presence of macrophages. Taken together, our results showed that these factors were important features for fungal virulence in humans and suggested that thermolabile components in the blood serum may induce M. circinelloides virulence.


Assuntos
Mucor/patogenicidade , Mucormicose/sangue , Soro/microbiologia , Esporos Fúngicos/metabolismo , Animais , Citocinas/metabolismo , Diabetes Mellitus Experimental , Humanos , Peróxido de Hidrogênio , Hifas/crescimento & desenvolvimento , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Pulmão , Macrófagos/microbiologia , Masculino , Camundongos , RNA Mensageiro/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Virulência
19.
Environ Sci Pollut Res Int ; 26(19): 19843-19858, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31090009

RESUMO

Globalization has led countries to a strong interdependence among them, which is reflected in trade and capital flows. Simultaneously, in recent decades, the world is rapidly urbanizing. This dynamic has generated a process of economic growth with serious consequences for the environment, particularly in air quality. In this context, the objective of this research is to examine the causal link among carbon dioxide emissions per capita as a measure of air pollution, real per capita output, FDI, trade openness, and urbanization in 100 countries during 1980-2017. First, we used the cointegration test of Pedroni (JAMA 61:653-670, 1999) and Westerlund (JAMA 69:709-748, 2007) to find the equilibrium long and short term, respectively, and the Dumitrescu and Hurlin (JAMA 29:1450-1460, 2012) test to verify the direction of causality among the series. Second, we estimate the strength of the cointegration vector for individual countries through a dynamic ordinary least squares model (DOLS), and for country groups using a dynamic panel model with ordinary least squares (PDOLS). The results found indicate the existence of short- and long-term equilibrium among the variables globally and by groups of countries. The strength of the cointegration vector is strong in high and middle-high-income countries. At a global level, the results of the causality test suggest the existence of a unidirectional causal relationship that goes from output, urbanization, and FDI to air pollution, and a bidirectional relationship among trade and air pollution. These results are sensitive to the inclusion of the level of development of the countries. Our results suggest that the mechanisms to increase output, along with commercial and FDI flows, and urbanization are factors that play a relevant role in the determination of air pollution. Consequently, public policies should take these aspects into account in efforts to mitigate air pollution.


Assuntos
Poluição do Ar/análise , Dióxido de Carbono/análise , Comércio , Desenvolvimento Econômico , Investimentos em Saúde , Urbanização , Análise dos Mínimos Quadrados , Modelos Econométricos
20.
J Antimicrob Chemother ; 74(5): 1253-1259, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30753471

RESUMO

OBJECTIVES: This study investigated the presence of the crpP gene, which encodes an enzymatic mechanism of antibiotic phosphorylation that decreases ciprofloxacin susceptibility, in ESBL-producing clinical isolates and its effect in transconjugants. METHODS: A collection of 77 ESBL-producing clinical isolates of Enterobacteriaceae and 68 ESBL-producing transconjugants that had acquired plasmids from clinical isolates from hospitals in Mexico obtained from 1988 to 2012 was employed. The crpP homologue genes were identified by dot-blot and PCR assays; five of them were sequenced and an in silico analysis was conducted. Expression of CrpP proteins was determined by western blot assays using antibodies against CrpP from plasmid pUM505. Three crpP homologue genes were cloned and transferred to Escherichia coli J53-3 as recipient strain. RESULTS: The crpP gene was identified in four (5.19%) ESBL-producing isolates and five (7.35%) ESBL-producing transconjugants with plasmids from clinical isolates. Analysis of the deduced amino acid (aa) sequence of the CrpP protein homologues revealed that they all corresponded to small proteins (63-70 aa) with an identity of 10.1%-43.7% with respect to the pUM505 CrpP sequence. In addition, all crpP-positive transconjugants expressed a CrpP protein. Finally, transfer of crpP homologues conferred lower ciprofloxacin susceptibility to E. coli. CONCLUSIONS: These findings indicate the presence of crpP genes among ESBL-producing isolates from Mexican hospitals and point to widespread crpP-type genes in old Enterobacteriaceae clinical isolates (from 1994). CrpP probably confers resistance by means of the phosphorylation of ciprofloxacin.


Assuntos
Proteínas de Bactérias/genética , Ciprofloxacina/farmacologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Sequência de Aminoácidos , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Clonagem Molecular , Conjugação Genética , Farmacorresistência Bacteriana , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Fases de Leitura Aberta , Plasmídeos/genética , Prevalência
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