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1.
Phys Chem Chem Phys ; 24(38): 23076-23081, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36069334

RESUMO

The conformational landscape of ß-D-allose, a rare sugar, was investigated using laser ablation in combination with high-resolution rotational spectroscopy. Altogether, three species are identified, exhibiting a counter-clockwise intramolecular hydrogen bond network. The effect of epimerization on the main aldohexose is also studied and, despite the main conformers being very similar, the position of the hydroxyl groups in allose allows the formation of considerably stronger intramolecular hydrogen bonds than in glucose, and this could explain the low abundance of ß-D-allose in Nature.


Assuntos
Glucose , Açúcares , Glucose/química , Ligação de Hidrogênio
2.
J Phys Chem A ; 126(42): 7621-7626, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36099577

RESUMO

In the present work, we report the first rotational study of N-acetylgalactosamine, a cancer-associated sugar derivative, by means of high-resolution rotational spectroscopy. Two different conformers have been conclusively characterized using broadband Fourier transform microwave spectroscopy coupled with a laser ablation vaporization system. Additionally, we performed a comprehensive analysis of the intramolecular interactions that govern these structures, which allowed us to both characterize the existence of intramolecular hydrogen bond networks that drive the intrinsic conformation panorama of N-acetylgalactosamine and further rationalize the biological role of this aminosugar derivative as part of the Tn antigen.


Assuntos
Acetilgalactosamina , Neoplasias , Humanos , Conformação Molecular , Ligação de Hidrogênio , Compostos Orgânicos , Açúcares
3.
Ecotoxicol Environ Saf ; 150: 159-167, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29275183

RESUMO

Xenobiotics such as bisphenol A (BPA), are present in biosolids, which are applied as organic fertilizers in agricultural fields. Their effects on soil life have been poorly assessed, and this is particularly important in the case of earthworms, which represent the main animal biomass in this medium. In the present work we study the impacts of BPA on gene expression of Eisenia fetida, a widely used ecotoxicological model. Chronic soil tests and acute contact tests were performed, and gene expression was analyzed in total tissue and in masculine reproductive organs of the earthworms. The genes studied in this research played a role in endocrine pathways, detoxification mechanisms, stress response, epigenetics, and genotoxicity. Most of the genes were identified for the first time, providing potentially useful biomarkers for future assessments. For chronic exposures, no changes were detected in whole-body tissue; however, masculine reproductive organs showed changes in the expression of genes related to endocrine function (EcR, MAPR, AdipoR), epigenetic mechanisms (DNMTs), genotoxicity (PARP1), and stress responses (HSC70 4). For acute exposures, the expression of one epigenetic-related gene was altered for both whole-body tissues and male reproductive organs (Piwi2). Further changes were detected for whole-body tissues involved in detoxification (Metallothionein), stress (HSC70 4), and genotoxicity (PARP1) mechanisms. Acute exposure effects were also tested in whole-body tissues of juveniles, showing changes in the expression of Metallothionein and Piwi2. The molecular changes found in the analyzed earthworms indicate that exposure to BPA may have negative implications in their populations. Particularly interesting are the alterations related to epigenetic mechanisms, which suggest that future generations may be impacted. This study is the first to evaluate the molecular effects of BPA on soil organisms, and further assays will be necessary to better characterize the true environmental repercussions. CAPSULE: Levels of gene expression in total-body tissues and masculine reproductive organs were analyzed in earthworms after exposure to bisphenol A and we observed associated changes in detoxification, endocrine, epigenetic, genotoxic and stress pathways.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Expressão Gênica/efeitos dos fármacos , Oligoquetos/efeitos dos fármacos , Fenóis/toxicidade , Poluentes do Solo/toxicidade , Animais , Biomarcadores/metabolismo , Ecotoxicologia , Oligoquetos/genética , Solo/química
4.
Nutr Metab Cardiovasc Dis ; 28(2): 143-149, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29329924

RESUMO

BACKGROUND AND AIM: Oxidative stress plays a pivotal role in inducing endothelial dysfunction and progression from simple fatty liver steatosis (FLD) to non-alcoholic steatohepatitis (NASH). Polyphenols could reduce oxidative stress and restore endothelial function by inhibiting the nicotinamide-adenine-dinucleotide-phosphate (NADPH) oxidase isoform Nox2. The aim of this study was to assess endothelial function and oxidative stress in a population affected by simple FLD and NASH. Furthermore, we analysed the effect of high vs low content of cocoa polyphenols on endothelial function and oxidative stress in patients with NASH. METHODS: In a cross-sectional study we analysed endothelial function, as assessed by flow-mediated dilation (FMD), and oxidative stress, as assessed by Nox2 activation, serum isoprostanes and nitric oxide bioavailability (NOx), in patients with NASH (n = 19), FLD (n = 19) and controls (n = 19). Then, we performed a randomized, cross-over study in 19 subjects with NASH comparing the effect of 14-days administration of 40 g of chocolate at high (dark chocolate, cocoa >85%) versus low content (milk chocolate, cocoa <35%) of polyphenols on FMD and oxidative stress. Compared to controls, NASH and FLD patients had higher Nox2 activity and isoprostanes levels and lower FMD and NOx, with a significant gradient between FLD and NASH. The interventional study showed that, compared to baseline, FMD and NOx increased (from 2.9 ± 2.4 to 7.2 ± 3.0% p < 0.001 and from 15.9 ± 3.6 to 20.6 ± 4.9 µM, p < 0.001, respectively) in subjects given dark but not in those given milk chocolate. A simple linear regression analysis showed that Δ (expressed by difference of values between before and after 14 days of chocolate assumption) of FMD was associated with Δ of Nox2 activity (Rs = -0.323; p = 0.04), serum isoprostanes (Rs: -0.553; p < 0.001) and NOx (Rs: 0.557; p < 0.001). CONCLUSIONS: Cocoa polyphenols improve endothelial function via Nox2 down-regulation in NASH patients.


Assuntos
Artéria Braquial/fisiopatologia , Chocolate , Endotélio Vascular/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Vasodilatação , Adulto , Biomarcadores/sangue , Artéria Braquial/metabolismo , Estudos Cross-Over , Estudos Transversais , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Endotélio Vascular/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , NADPH Oxidase 2/sangue , Óxido Nítrico/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Estresse Oxidativo , Cidade de Roma , Fatores de Tempo , Resultado do Tratamento
5.
Nutr Metab Cardiovasc Dis ; 27(10): 890-895, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28743559

RESUMO

BACKGROUND AND AIM: Impaired fasting glucose (IFG) is associated with an increased risk of cardiovascular disease but the underlying mechanisms are still unclear. Aim of the study was to investigate the interplay between platelet activation, lipopolysaccharides (LPS) and markers of oxidative stress in patients with IFG and control subjects. METHODS AND RESULTS: We performed a cross-sectional study including 35 patients with IFG and 35 control subjects who were well comparable for age, sex, body mass index and smoking history. Serum levels of LPS, zonulin (a marker of gut permeability), oxidized LDL and plasma levels of soluble P-selectin, were measured. Patients with IFG had significantly higher levels of sP-selectin, LPS, zonulin and oxLDL compared to control subjects. The IFG status (beta coefficient: 0.518, p < 0.001), higher LPS (beta coefficient: 0.352, p = 0.001) and female sex (beta coefficient: 0.179, p = 0.042) were independently associated with higher sP-selectin; in addition, oxLDL was positively associated with sP-selectin (r = 0.530, p < 0.001) and LPS (r = 0.529, p = 0.001). In IFG patients, we found a significant association between LPS and zonulin (r = 0.521, p = 0.001); this association was confirmed at multivariable analysis (beta coefficient: 0.512, p = 0.007). CONCLUSION: Our study provides evidence that patients with IFG have increased platelet activation, and suggests LPS as a potential trigger for in vivo platelet activation in this patient population.


Assuntos
Glicemia/metabolismo , Endotoxemia/sangue , Jejum/sangue , Trato Gastrointestinal/metabolismo , Intolerância à Glucose/sangue , Ativação Plaquetária , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Toxina da Cólera/sangue , Estudos Transversais , Endotoxemia/diagnóstico , Feminino , Intolerância à Glucose/diagnóstico , Haptoglobinas , Humanos , Modelos Lineares , Lipopolissacarídeos/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estresse Oxidativo , Selectina-P/sangue , Permeabilidade , Precursores de Proteínas
6.
Med Vet Entomol ; 30(3): 301-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27279553

RESUMO

Wolbachia pipientis (Rickettsiales: Rickettsiaceae) protects mosquitoes from infections with arboviruses and parasites. However, the effect of its co-infection on vector competence for Dirofilaria immitis (Spirurida: Onchocercidae) in the wild has not been investigated. This study aimed to screen vectors of D. immitis for wPip, to characterize these, and to investigate a possible association between the occurrence of W. pipientis and that of the nematode. The presence of W. pipientis was assessed in the five mosquito potential vectors of D. immitis in Portugal. Polymerase chain reaction (PCR) products were sequenced, and wPip haplotypes were determined by PCR-restricted fragment length polymorphism (RFLP). Results showed that wPip was detected in 61.5% of Culex pipiens (Diptera: Culicidae) pools and 6.3% of Culex theileri pools. wPip 16s rRNA sequences found in Cx. theileri exactly match those from Cx. pipiens, confirming a mosquito origin, rather than a nematode origin, as some specimens were infected with D. immitis. Only wPip haplotype I was found. No association was found between the presence of wPip and D. immitis in mosquitoes and hence a role for this endosymbiont in influencing vectorial competence is yet to be identified. This study contributes to understanding of wPip distribution in mosquito populations and, to the best of the authors' knowledge, is the first report of natural infections by wPip in Cx. theileri.


Assuntos
Culex/microbiologia , DNA Bacteriano/genética , Mosquitos Vetores/microbiologia , RNA Ribossômico 16S/genética , Wolbachia/isolamento & purificação , Animais , Culex/parasitologia , Dirofilaria immitis/isolamento & purificação , Dirofilariose/parasitologia , Dirofilariose/transmissão , Haplótipos , Mosquitos Vetores/parasitologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Portugal , Wolbachia/genética
7.
Heredity (Edinb) ; 112(2): 132-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24045291

RESUMO

Communities of organisms inhabiting extreme terrestrial environments provide a unique opportunity to study evolutionary forces that drive population structure and genetic diversity under the combined challenges posed by multiple geogenic stressors. High abundance of an invasive pantropical earthworm (and the absence of indigenous lumbricid species) in the Furnas geothermal field (Sao Miguel Island, Azores) indicates its remarkable tolerance to high soil temperature, exceptionally high carbon dioxide and low oxygen levels, and elevated metal bioavailability, conditions which are lethal for the majority of terrestrial metazoans. Mitochondrial and nuclear markers were used to analyze the relationship between populations living inside and outside the geothermal field. Results showed that Pontoscolex corethrurus (Annelida, Oligochaeta, Glossoscolecidae) to be a genetically heterogeneous complex within the Sao Miguel landscape and is probably differentiated into cryptic species. The population exposed to the hostile soil conditions within the volcanic caldera possesses the lowest within-population mitochondrial diversity but an unexpectedly high degree of nuclear variability with several loci evidencing positive selection, parameters indicative of a genetically unique population only distantly related to conspecifics living outside the caldera. In conclusion, P. corethrurus inhabiting active volcanic soil is a discrete extremophile population that has evolved by tolerating a mixture of non-anthropogenic chemical and physical stressors.


Assuntos
Oligoquetos/genética , Solo , Animais , DNA Mitocondrial , Variação Genética , Genética Populacional , Genótipo , Dados de Sequência Molecular , Oligoquetos/classificação , Filogenia
8.
Public Health ; 127(3): 214-22, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23375366

RESUMO

OBJECTIVES: To analyse the associations between unemployment and suboptimal self-rated health as well as high alcohol consumption, and to examine the role of possible mediating factors explaining the associations from a gender perspective. STUDY DESIGN: The sample, from a 14-year longitudinal study with a 96.4% response rate, consisted of 386 women and 478 men who were either employed or unemployed at 30 years of age. METHODS: The health outcomes studied were suboptimal self-rated health and high alcohol consumption at 30 years of age. Logistic regression was used for analysis, and the relational theory of gender was used to discuss the findings. RESULTS: A strong relationship was found between unemployment and suboptimal self-rated health among women, and unemployment and high alcohol consumption among men, even after controlling for health-related selection, potential mediators and background factors. All mediating factors in the model were attributable to suboptimal self-rated health among unemployed women. Two mediating factors were also substantially related to high alcohol consumption among unemployed men. CONCLUSIONS: Long-term unemployment at a young age could have various health effects in men and women. At present, the mechanisms behind the health consequences are better understood among women. Research would benefit from developing theories in order to explain how youth unemployment leads to gendered health consequences.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Autoavaliação Diagnóstica , Desemprego/estatística & dados numéricos , Adulto , Feminino , Seguimentos , Humanos , Masculino , Fatores de Risco , Suécia/epidemiologia
9.
Euro Surveill ; 17(49)2012 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-23231893

RESUMO

Following the identification of two autochthonous cases of dengue type 1 on 3 October 2012, an outbreak of dengue fever has been reported in Madeira, Portugal. As of 25 November, 1,891 cases have been detected on the island where the vector Aedes aegypti had been established in some areas since 2005. This event represents the first epidemic of dengue fever in Europe since 1928 and concerted control measures have been initiated by local health authorities.


Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Dengue/epidemiologia , Surtos de Doenças , Adolescente , Adulto , Aedes/virologia , Idoso , Animais , Criança , Pré-Escolar , Dengue/transmissão , Notificação de Doenças , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Vigilância de Evento Sentinela , Análise de Sequência , Viagem , Adulto Jovem
10.
Genet Mol Res ; 11(4): 4043-57, 2012 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-23212341

RESUMO

Xanthomonas citri subsp citri (Xac) is the bacterium responsible for citrus canker disease in citrus plants. The aim of this study was to describe the recombinant expression, purification, and characterization of a cysteine peptidase from Xac strain 306, which is a candidate for involvement in the pathogenicity of this bacterium. The gene was cloned and expressed in Pichia pastoris, and the cysteine peptidase was successfully expressed, secreted, and purified using affinity chromatography with a yield of approximately 10 mg/L. A polyclonal antibody produced against cysteine peptidase from X. citri subsp citri fused with HIS tag ((HIS)CPXAC) recognized the purified recombinant cysteine peptidase (HIS)CPXAC, confirming the correct production of this protein in P. pastoris. The same antibody detected the protein in the culture supernatant of Xac grown in pathogenicity-inducing medium. Kinetic analysis revealed that (HIS)CPXAC hydrolyzed the carbobenzoxy-Leu-Arg-7-amido-4-methylcoumarin substrate with a catalytic efficiency (k(cat)/K(m)) of 47 µM(-1)∙s(-1). The purified ((HIS))CPXAC displayed maximal catalytic activity at pH 5.5 and 30°C. The recombinant enzyme was inhibited by the specific cysteine peptidase inhibitor E-64, as well as by the recombinant cysteine peptidase inhibitors CaneCPI-1, CaneCPI-2, CaneCPI-3, and CaneCPI-4, with K(i) values of 1.214, 84.64, 0.09, 0.09, and 0.012 nM, respectively. Finally, the N-terminal sequencing of the purified protein enabled the identification of the first 5 amino acid residues (AVHGM) immediately after the putative signal peptide, thereby enabling the identification of the cleavage point and corroborating previous studies that have identified this sequence in a secreted protein from Xanthomonas spp.


Assuntos
Cisteína Proteases/metabolismo , Proteínas Recombinantes/metabolismo , Xanthomonas/enzimologia , Sequência de Aminoácidos , Biocatálise/efeitos dos fármacos , Biologia Computacional , Meios de Cultura , Cisteína Proteases/química , Ativação Enzimática/efeitos dos fármacos , Ensaios Enzimáticos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Inibidores de Proteases/farmacologia , Alinhamento de Sequência , Análise de Sequência de Proteína , Temperatura , Xanthomonas/efeitos dos fármacos , Xanthomonas/patogenicidade
12.
RSC Adv ; 13(1): 212-219, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36605649

RESUMO

This work reports a complete conformational analysis of caffeic acid, an exceptionally versatile pharmacophore, using laser ablation chirped-pulse Fourier transform microwave spectroscopy. The whole conformational space consisting of eight distinct species has been fully deciphered based on the trend of the rotational constants supported by theoretical computations. We show how rotational spectroscopy can be confidently used to distinguish between conformers even when the structural differences are minimal, such as those involved in the conformational panorama of caffeic acid. Additionally, the structural information here provided, such as the planarity observed in all the conformers, could help to elucidate the mechanisms underlying the biological and pharmacological activity of hydroxycinnamic acids.

13.
Curr Issues Mol Biol ; 12(1): 1-10, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19478349

RESUMO

Coeliac disease (CD) development involves genetic (HLA-DQ2/DQ8) and environmental factors. Herein, the influence of the HLA-DQ genotype on the gut colonization process of breast-fed children was determined. A cohort of 20 newborns, with at least one first-degree relative with CD, were classified according to their HLA-DQ genotype into high, intermediate and low genetic risk groups, showing 24-28%, 7-8% and less than 1% probability to develop CD, respectively. Faecal microbiota was analysed at 7 days, 1 and 4 months of children's age by fluorescence in situ hybridization. When considering all data, Gram-negative bacteria and Bacteroides-Prevotella group proportions were higher (P<0.05) in the high than in the intermediate and low genetic risk groups. E. coli, Streptococcus-Lactococcus, E. rectale-C. coccoides, sulphate-reducing bacteria, C. lituseburense and C. histolyticum group proportions were also significantly higher (P<0.05) in the high than in the low genetic risk group. Correlations between these bacterial groups and the genetic risk were also detected (P<0.05). In addition, the number and type of CD relative seemed to influence (P<0.050) these bacterial proportions in children at CD risk. At 4 months of age, similar relationships were established between the high genetic risk to develop CD and the proportions of Streptococcus-Lactococcus (P<0.05), E. rectale-C. coccoides (P<0.05), C. lituseburense (P<0.05), C. histolyticum (P<0.05), Bacteroides-Prevotella (P<0.10) groups and total Gram-negative bacteria (P<0.05). The results suggest a relationship between HLA-DQ genes and the gut microbial colonization process that could lead to a change in the way this disorder is investigated.


Assuntos
Antígenos HLA-DQ/genética , Intestinos/microbiologia , Bacteroides/crescimento & desenvolvimento , Bacteroides/isolamento & purificação , Citometria de Fluxo , Genótipo , Cadeias alfa de HLA-DQ , Cadeias beta de HLA-DQ , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Lactococcus/crescimento & desenvolvimento , Lactococcus/isolamento & purificação , Prevotella/crescimento & desenvolvimento , Prevotella/isolamento & purificação , Streptococcus/crescimento & desenvolvimento , Streptococcus/isolamento & purificação
14.
Astron Astrophys ; 6442020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33594291

RESUMO

CONTEXT: Cyanoacetamide is a -CN bearing molecule that is also an amide derivative target molecule in the interstellar medium. AIMS: The aim of our investigation is to analyze the feasibility of a plausible formation process of protonated cyanoacetamide under interstellar conditions and to provide direct experimental frequencies of the ground vibrational state of the neutral form in the microwave region in order to enable its eventual identification in the interstellar medium. METHODS: We used high-level theoretical computations to study the formation process of protonated cyanoacetamide. Furthermore, we employed a high-resolution laser-ablation molecular beam Fourier transform spectroscopic technique to measure the frequencies of the neutral form. RESULTS: We report the first rotational characterization of cyanoacetamide, and a precise set of the relevant rotational spectroscopic constants have been determined as a first step to identifying the molecule in the interstellar medium. We fully explored the potential energy surface to study a gas-phase reaction on the formation process of protonated cyanoacetamide. We found that an exothermic process with no net activation barrier is initiated by the high-energy isomer of protonated hydroxylamine, which leads to protonated cyanoacetamide.

15.
Med Intensiva (Engl Ed) ; 44(1): 18-26, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30195445

RESUMO

OBJECTIVE: To evaluate if there is an association between obesity and mortality in the Intensive Care Unit (ICU) in adult patients receiving invasive mechanical ventilation. DESIGN: Systematic review with meta-analysis. SCOPE: ICU. DATA SOURCE: A search was made in MEDLINE, Cochrane Library, CINAHL and Global Health databases without language restriction, until February 21, 2017. SELECTION OF STUDIES: Studies that reported mortality in the ICU in obese versus non-obese patients who received IMV were included. MAIN VARIABLES: Mortality in the ICU. RESULTS: 2163 articles were found, of which 14 studies were included. No statistically significant differences were found between obese and non-obese patients with respect to the variable mortality in the ICU (OR: 0.94, 95% CI: 0.81-1.10, P=.45). CONCLUSION: No relationship was found between the subgroup of obese adult patients receiving IMV and the mortality variable in the ICU.


Assuntos
Mortalidade Hospitalar , Unidades de Terapia Intensiva , Obesidade/mortalidade , Respiração Artificial/mortalidade , Índice de Massa Corporal , Intervalos de Confiança , Humanos , Tempo de Internação , Razão de Chances , Estudos Prospectivos , Viés de Publicação , Estudos Retrospectivos
16.
Astron Astrophys ; 6392020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33154598

RESUMO

CONTEXT: Glycolamide is a glycine isomer and also one of the simplest derivatives of acetamide (e.g., one hydrogen atom is replaced with a hydroxyl group), which is a known interstellar molecule. AIMS: In this context, the aim of our work is to provide direct experimental frequencies of the ground vibrational state of glycolamide in the centimeter-, millimeter- and submillimeter-wavelength regions in order to enable its identification in the interstellar medium. METHODS: We employed a battery of state-of-the-art rotational spectroscopic techniques in the frequency and time domain to measure the frequencies of glycolamide. We used the spectral line survey named Exploring Molecular Complexity with ALMA (EMoCA), which was performed toward the star forming region Sgr B2(N) with ALMA to search for glycolamide in space. We also searched for glycolamide toward Sgr B2(N) with the Effelsberg radio telescope. The astronomical spectra were analyzed under the local thermodynamic equilibrium approximation. We used the gas-grain chemical kinetics model MAGICKAL to interpret the results of the astronomical observations. RESULTS: About 1500 transitions have been newly assigned up to 460 GHz to the most stable conformer, and a precise set of spectroscopic constants was determined. Spectral features of glycolamide were then searched for in the prominent hot molecular core Sgr B2(N2). We report the nondetection of glycolamide toward this source with an abundance at least six and five times lower than that of acetamide and glycolaldehyde, respectively. Our astrochemical model suggests that glycolamide may be present in this source at a level just below the upper limit, which was derived from the EMoCA survey. We could also not detect the molecule in the region's extended molecular envelope, which was probed with the Effelsberg telescope. We find an upper limit to its column density that is similar to the column densities obtained earlier for acetamide and glycolaldehyde with the Green Bank Telescope.

17.
Sci Total Environ ; 676: 97-104, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31029904

RESUMO

The use of organic Ultraviolet (UV) filters has increased in the last years, either in sunscreens, other cosmetics, or even food packaging. These filters may end up in soil and water since the Wastewater Treatment Plants may not successfully remove them. Among them, benzophenones are known to act as endocrine disruptors. However, most of the studies are directed towards vertebrates and aquatic invertebrates, while there is a lack of information on the molecular mechanisms affected by these compounds on soil dwelling invertebrates. Here, we study the impact of direct acute (48 h) contact of 4-hydroxybenzophenone (4-OHBP) at two sublethal concentrations (0.02 and 0.2 mg/mL) on gene expression of the earthworm Eisenia fetida. Investigated genes were involved in endocrine pathways, stress response, detoxification mechanisms, genotoxicity, energy metabolism and epigenetics. Three of them were identified for the first time in earthworms. Our results suggest that exposure to 4-OHBP affected endocrine pathways, causing an increase in the Ecdysone receptor gene (EcR) expression. Moreover, the UV filter induced changes in the CuZn superoxide dismutase gene (CuZn SOD), indicating an effect in the stress response. Finally, significant changes were detected for glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH) expression, indicating that energy metabolism is influenced by the 4-OHBP and highlighting the risks of using GAPDH as an internal reference for Real Time PCR.


Assuntos
Disruptores Endócrinos/toxicidade , Oligoquetos/fisiologia , Protetores Solares/toxicidade , Animais , Sistema Endócrino/efeitos dos fármacos , Receptores de Esteroides/metabolismo , Superóxido Dismutase/metabolismo
18.
Trans R Soc Trop Med Hyg ; 102(8): 823-32, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18455742

RESUMO

Circulation of West Nile virus in Portugal was demonstrated by serological surveys, and the virus was isolated in 1969 from Anopheles maculipennis s.l. A survey of the whole country was carried out (2001-2004) to assess the abundance of mosquito species and to screen them for arbovirus infection. A total of 770 collections yielded 32460 mosquitoes of 15 species. The regions with the highest abundance of mosquitoes were the coastal and estuarine districts of Santarém, Setúbal and Faro. Culex pipiens s.l., An. maculipennis s.l., Cx. theileri and Ochlerotatus caspius were the most abundant and widespread, accounting for 92% of mosquitoes caught. Anopheles maculipennis s.l. and Cx. pipiens s.l. were present all over the country. Culex theileri and. Oc. caspius were more abundant in the southern and coastal areas, respectively. A total of 2355 mosquito pools were screened by RT-PCR for flaviviruses, of which 987 pools were also screened for bunyaviruses. Culex pipiens s.l. and Cx. univittatus collected in 2004 in the southern district of Faro were found to be infected with West Nile virus. The density and proximity of these mosquitoes to the human populations may constitute a public health threat in the case of involvement in arbovirus transmission cycles.


Assuntos
Arbovírus/isolamento & purificação , Culicidae/virologia , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Monitoramento Ambiental , Monitoramento Epidemiológico , Interações Hospedeiro-Parasita/fisiologia , Humanos , Portugal/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Febre do Nilo Ocidental/epidemiologia
19.
Int J Food Microbiol ; 126(1-2): 116-22, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18619697

RESUMO

In winemaking, spontaneous grape must fermentations have been replaced by inoculation of commercial active dry wine yeast (ADWY). Yeast rehydration is the key to avoiding stuck and sluggish fermentations. Despite the importance of this step, not enough is known about what this process implies for winemaking as a whole or about what kind of practices could help to improve it. The main aim of this study is to determine the best yeast rehydration conditions for ensuring good cell viability and vitality before inoculation into the must. The experimental rehydration media in this study can be divided into four groups: carbon and nitrogen compounds, metallic ions, oxidant and antioxidant agents, and membrane fluidity agents. We studied the biochemical and biophysical behaviour of ADWY after rehydration in the various media under oenological conditions, i.e. incubation at 37 degrees C for 30 min. The viability of rehydrated yeast cells was evaluated by plating, and assessed by fluorescence microscopy and flow cytometry. The vitality of rehydrated cells was estimated by indirect impedance. The rehydrating solution complemented with magnesium provided the best vitality rate because the time taken to reach the activity threshold was cut by two thirds. This improvement was also illustrated by the less time needed to stop the leakage of intracellular compounds during the rehydration process.


Assuntos
Microbiologia Industrial , Água/farmacologia , Vinho/microbiologia , Leveduras/fisiologia , Carbono/farmacologia , Contagem de Colônia Microbiana , Dessecação , Fermentação , Citometria de Fluxo , Magnésio/farmacologia , Microscopia de Fluorescência , Nitrogênio/farmacologia , Vinho/normas
20.
Chemosphere ; 190: 287-295, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28992482

RESUMO

The application of biosolids in agricultural fields is increasing annually. They contain not only nutrients but also xenobiotics, such as Bisphenol A (BPA). These compounds are not regulated in the use of biosolids in agriculture, which highlights the need to assess their effects on soil life, of which earthworms are most abundant of the animal representatives. In this study the effect of BPA on life-history parameters, such as mortality, growth and reproduction, and on immunity, is evaluated for Dendrobaena veneta and Eisenia fetida. Sublethal concentrations were evaluated by a modified OECD artificial soil test. Decline in growth with increasing concentration of BPA was detected during the first two weeks and the opposite effect for the next two, although these differences were only significant at the highest concentration. Reproduction traits were only significantly different for E. fetida, for which the number of juveniles decreased at higher concentrations, thus showing different sensitivity in both species. By using a contact test, the potentially harmful effect of direct contact with BPA was shown to be much higher than in soil (resembling natural) conditions. Finally, results indicate that BPA may not affect the immune system of these animals, at least in terms of coelomocyte viability.


Assuntos
Compostos Benzidrílicos/farmacologia , Oligoquetos/efeitos dos fármacos , Fenóis/farmacologia , Solo/química , Animais , Relação Dose-Resposta a Droga , Oligoquetos/crescimento & desenvolvimento , Oligoquetos/imunologia , Oligoquetos/fisiologia , Reprodução/efeitos dos fármacos , Poluentes do Solo/análise , Poluentes do Solo/farmacologia , Especificidade da Espécie
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