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1.
Data Brief ; 36: 107019, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33937454

RESUMO

Forager Apis melliefera honeybees were collected from four localities located in Europe, i.e.: London, UK; Athens, Greece; Marchamalo, Spain and Lublin, Poland. Furthermore, from Asia we have collected A. mellifera as well as A. cerana foragers form Chiang Mai in Thailand We used next generation sequencing (NGS) to analyse the 16S rRNA bacterial gene amplicons based on the V3-V4 region and the ITS2 region from fungi and plants derived from honeybee samples. Amplicon libraries, were prepared using the 16S Metagenomic Sequencing Library Preparation, Preparing 16S Ribosomal RNA Gene Amplicons for the Illumina MiSeq System (Illumina®) protocol. NGS raw data are available at https://www.ncbi.nlm.nih.gov/bioproject/PRJNA686953. Furthermore, isolated DNA was used as the template for screening pathogens: Nosema apis, N. ceranae, N. bombi, tracheal mite (Acarapis woodi), any organism in the parasitic order Trypanosomatida, including Crithidia spp. (i.e., Crithidia mellificae), neogregarines including Mattesia and Apicystis spp. (i.e., Apicistis bombi). The presented data can be used to compare the metagenomic samples from different honeybee population all over the world. A higher load of fungi, and bacteria groups such as: Firmicutes (Lactobacillus); γ- proteobacteria, Neisseriaceae, and other unidentified bacteria was observed for Nosema cearana and neogregarines infected honeybees. Healthy honeybees had a higher load of plant pollens, and bacteria groups such as: Orbales, Gilliamella, Snodgrassella, and Enterobacteriaceae. More details can be found in research article [1] Ptaszynska et al. 2021.

2.
Pathogens ; 10(3)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810160

RESUMO

European Apis mellifera and Asian Apis cerana honeybees are essential crop pollinators. Microbiome studies can provide complex information on health and fitness of these insects in relation to environmental changes, and plant availability. Amplicon sequencing of variable regions of the 16S rRNA from bacteria and the internally transcribed spacer (ITS) regions from fungi and plants allow identification of the metabiome. These methods provide a tool for monitoring otherwise uncultured microbes isolated from the gut of the honeybees. They also help monitor the composition of the gut fungi and, intriguingly, pollen collected by the insect. Here, we present data from amplicon sequencing of the 16S rRNA from bacteria and ITS2 regions from fungi and plants derived from honeybees collected at various time points from anthropogenic landscapes such as urban areas in Poland, UK, Spain, Greece, and Thailand. We have analysed microbial content of honeybee intestine as well as fungi and pollens. Furthermore, isolated DNA was used as the template for screening pathogens: Nosema apis, N. ceranae, N. bombi, tracheal mite (Acarapis woodi), any organism in the parasitic order Trypanosomatida, including Crithidia spp. (i.e., Crithidia mellificae), neogregarines including Mattesia and Apicystis spp. (i.e., Apicistis bombi). We conclude that differences between samples were mainly influenced by the bacteria, plant pollen and fungi, respectively. Moreover, honeybees feeding on a sugar based diet were more prone to fungal pathogens (Nosema ceranae) and neogregarines. In most samples Nosema sp. and neogregarines parasitized the host bee at the same time. A higher load of fungi, and bacteria groups such as Firmicutes (Lactobacillus); γ-proteobacteria, Neisseriaceae, and other unidentified bacteria was observed for Nosema ceranae and neogregarine infected honeybees. Healthy honeybees had a higher load of plant pollen, and bacteria groups such as: Orbales, Gilliamella, Snodgrassella, and Enterobacteriaceae. Finally, the period when honeybees switch to the winter generation (longer-lived forager honeybees) is the most sensitive to diet perturbations, and hence pathogen attack, for the whole beekeeping season. It is possible that evolutionary adaptation of bees fails to benefit them in the modern anthropomorphised environment.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31301398

RESUMO

In fish of freshwaters environments, the accumulation and toxic effects of arsenite (AsIII) can be attenuated by detoxification proteins such as GST and ABCC transporters. We studied the effects of AsIII on the middle intestine of O. mykiss in ex-vivo and in vivo/ex vivo assays. For the ex vivo assays, we measured the transport rate of the ABCC substrate DNP-SG and GST activity in intestinal strips and everted sacs. AsIII inhibited DNP-SG transport in a concentration-dependent manner, specifically when we applied it on the basolateral side. GST activity increased when we applied a maximum concentration of AsIII. For the in vivo/ex vivo assays, we kept fish in water with or without 7.7 µmol L-1 of AsIII for 48 h. Then, we measured DNP-SG transport rate, GST activity, and PP1 activity in intestine strips during one hour. For PP1 activity, we incubated the strips with or without microcystin-LR (MCLR), a toxin excreted through ABCC2 proteins. We also analyzed Abcc2 and Gst-π mRNA expression in intestine and liver tissue. In the group exposed in vivo to AsIII, DNP-SG transport rate and GST activity were higher and the effect of MCLR over PP1 activity was attenuated. AsIII significantly induced only Abcc2 mRNA expression in both middle intestine and liver. Our results suggest that, in the middle intestine of O. mykiss, AsIII is absorbed mainly at the basolateral side of the enterocytes, excreted to the lumen by ABCC2 transporters, and is capable of modulating Abcc2 mRNA expression by a transcriptional mechanism.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Arsenitos , Glutationa S-Transferase pi/metabolismo , Intestinos/enzimologia , Fígado/metabolismo , Oncorhynchus mykiss/metabolismo , Animais , Arsenitos/metabolismo , Arsenitos/farmacocinética , Arsenitos/toxicidade , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , RNA Mensageiro , Xenobióticos/metabolismo , Xenobióticos/farmacocinética , Xenobióticos/toxicidade
4.
J Invertebr Pathol ; 157: 36-44, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30099010

RESUMO

Immune cell characterization, immunological response and the associated gill oxidative balance were studied in the Patagonian freshwater mussel, Diplodon chilensis, using two microbiological immunostimulant models: Saccharomyces cerevisiae and Escherichia coli. Mussels were collected out of the breeding season in Paimún Lake and acclimated in the laboratory. Two exposure experiments were performed during two consecutive weeks: (1) mussels challenged with 500 yeast cells mL-1; and (2) mussels challenged with 1000 bacteria cells mL-1. Microorganisms were added in the water every two days, alternating with 6000 lyophilized cells of the green algae Scenedesmus vacuolatus mL-1. A control group, fed with S. vacuolatus, was set for each treatment. Morphological cell characterization was carried out in adherent hemocytes of D. chilensis hemolymph under control conditions. The most important cell type observed were the hyalinocytes (representing ca. 98% of the circulating cells), agranular cells with non-central polymorphic nucleus surrounded by cytoplasm; granulocytes (cells with cytoplasmic granules and non-central rounded nucleus) represented ca. 2%. Another two cell types were occasionally detected, binucleated hyalinocytes and hemoblast-like cells but were not considered for the analyses. Both adherent hyalinocytes and granulocytes exhibit phagocytic activity towards Congo red stained yeast, which was two-fold higher in granulocytes than in hyalinocytes, regardless of the applied challenge. Total hemocyte counts were diminished in mussels challenged with S. cerevisiae or E. coli. Hydrolytic and defense cellular enzyme activities were analyzed only for hyalinocytes. Both, S. cerevisiae and E. coli increased acid phosphatase activity. E. coli challenge diminished hemocyte lysosomal membrane stability and increased humoral phenoloxidase activity, while S. cerevisiae challenge did not affect any of these variables. Mussels challenged with E. coli showed increased gill antioxidant response without oxidative damage, while those challenged with S. cerevisiae showed no change in these variables.


Assuntos
Bivalves/imunologia , Bivalves/microbiologia , Brânquias/imunologia , Hemolinfa/imunologia , Animais , Escherichia coli/imunologia , Infecções por Escherichia coli/imunologia , Micoses/veterinária , Saccharomyces cerevisiae/imunologia
5.
Environ Toxicol Chem ; 36(7): 1785-1794, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27600597

RESUMO

The aim of the present study was to characterize the immune response-total hemocyte number, cell type proportion, hemocyte viability, lysosomal membrane stability, phagocytic activity, cellular acid and alkaline phosphatase activity, and humoral bacteriolytic and phenoloxidase activity--in Diplodon chilensis exposed to 0.2 mg/L of azinphos-methyl (AZM), using Escherichia coli as immunological and pro-oxidant challenges. In addition, glutathione-S-transferase and lipid peroxidation thiobarbituric acid reactive substances were analyzed in gill tissue. Mussels from an unpolluted site were treated for 3 d as follows: 1) experimental control; 2) solvent effects control (acetone 0.01%); 3) bacterial challenge effects control (E. coli, 5 cells/mL × 104 cells/mL); 4) pesticide effects control (AZM in acetone); 5) control for combined effects of solvent and bacterial challenge; and 6) exposed to AZM, then challenged with E. coli. The results showed increased granulocyte proportion and phagocytic activity. Partial reversion of deleterious effects of E. coli on lysosomal membranes was observed in mussels exposed to AZM and then challenged with E. coli. Total hemocyte number and humoral bacteriolytic activity were increased only by E. coli challenge. Acid phosphatase activity was increased by both E. coli and AZM, whereas the stimulating effect of E. coli on alkaline phosphatase activity was negatively modulated by AZM. Azinphos-methyl inhibited phenoloxidase activity regardless of the E. coli challenge. Gill glutathione-S-transferase activity was increased by E. coli treatment either alone or pretreated with acetone or AZM and by AZM alone. Thiobarbituric acid reactive substance levels were reduced by AZM alone or combined with the E. coli challenge and by acetone followed by the E. coli challenge. Both acetone and AZM seem to be important modulators of immune and antioxidant responses in D. chilensis. Environ Toxicol Chem 2017;36:1785-1794. © 2016 SETAC.


Assuntos
Antioxidantes/metabolismo , Azinfos-Metil/toxicidade , Bivalves/efeitos dos fármacos , Escherichia coli/patogenicidade , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Fosfatase Alcalina/metabolismo , Animais , Bivalves/imunologia , Bivalves/metabolismo , Bivalves/microbiologia , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Hemócitos/efeitos dos fármacos , Hemócitos/imunologia , Imunidade Humoral/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Monofenol Mono-Oxigenase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/química
6.
Fish Shellfish Immunol ; 51: 17-25, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26892796

RESUMO

In order to test if orally supplied Euglena sp. cells modulate the physiological status of bivalves during bioremediation procedures, we evaluated the effect of Euglena gracilis diet on the immune response, oxidative balance and metabolic condition of Diplodon chilensis exposed to sewage water pollution. Mussels were fed for 90 days with E. gracilis (EG) or Scenedesmus vacuolatus (SV, control diet), and then exposed for 10 days at three sites along the Pocahullo river basin: 1) an unpolluted site, upstream of the city (control, C); 2) upstream (UpS) and 3) downstream (DoS) from the main tertiary-treated sewage discharge, in the city of San Martín de los Andes, Northwest Patagonia, Argentina. Our results show that the total hemocyte number decreases while pollution load increases along the river course for both, EG and SV mussels. Phagocytic activity is higher in EG mussels than in SV ones under all conditions. Reactive oxygen species (ROS) production in hemocytes increases with the increase in the pollution load, being significantly higher for EG mussels than for SV ones at DoS; no changes are observed for total oxyradical scavenging capacity (TOSC). Hemocytes' viability is increased for E. gracilis diet at C and remains unchanged in this group of mussels when exposed at the polluted sites. Lysosomal membrane stability is higher in EG mussels than in SV ones for all conditions, although it is decreased at polluted sites compared with that at C. Antioxidant (catalase) and detoxifying (gluthatione S-transferase) defenses are generally lower in gills and digestive gland of EG mussels than in SV ones. Lipid peroxidation (TBARS) is evident in gills of EG mussels at C, and in digestive gland of the same group, at all the sites. Gill mass factor (GF) is affected by the E. gracilis diet; it is increased at C and decreased at polluted sites when compared with that of SV ones. Digestive gland mass factor (DGF) is higher in EG mussels than in SV ones. In D. chilensis, continuous and long term feeding with E. gracilis cells favors immune response and reduces the damage caused by sewage pollution exposure on hemocytes. Nevertheless, diet and transplantation procedures may produce negative effects on the oxidative balance of gills and digestive gland and should be taken into account for bioremediation strategies.


Assuntos
Bivalves/imunologia , Dieta , Euglena gracilis/imunologia , Imunidade Inata , Esgotos/análise , Águas Residuárias/análise , Ração Animal/análise , Animais , Argentina , Bivalves/metabolismo , Hemócitos/imunologia , Oxirredução , Rios
7.
Psychopharmacology (Berl) ; 207(1): 57-71, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19711055

RESUMO

RATIONALE: Experimental evidence indicates that nicotine causes long-lasting changes in the brain associated with behavior. Although much has been learned about factors participating in this process, less is known concerning the mechanisms and brain areas involved in nicotine preference. OBJECTIVES: The objective of this study is to examine the participation of brain structures during the development of nicotine-conditioned place preference (CPP). METHODS: To identify brain regions activated in CPP, we have measured the levels of phosphorylated cyclic AMP response element binding protein (pCREB) and Fos protein using a behavioral CPP and conditioned place aversion (CPA) paradigms. RESULTS: Rats developed reliable and robust CPP and also CPA. During nicotine preference and reinstatement behaviors, a significant increase of both pCREB and Fos protein expression occurs in the nucleus accumbens (NAc) and ventral tegmental area (VTA) and also in the prefrontal cortex (PFC), dorsal striatum (DStr), amygdala, and hippocampus. These increases were abolished by the administration of mecamylamine or by a CPA protocol, showing a specific activation of pCREB in drug preference animals, mediated by nicotinic receptors. Specifically in the VTA, nicotine-induced preference and reinstatement of the preference caused the activation of dopaminergic and GABAergic cells in different proportions. CONCLUSION: The results indicate that the phosphorylation of CREB and expression of Fos protein, as indicators of neural activity, accompany the acquisition and maintenance of nicotine-induced CPP but not CPA in mesolimbic areas (NAc, VTA, PFC, and DStr) as well as in memory consolidation structures (hippocampus and amygdala) and nicotinic receptor are involved in this process. Taken together, these studies identify the brain regions where pCREB activity is essential for nicotine preference.


Assuntos
Encéfalo/efeitos dos fármacos , Proteína de Ligação a CREB/metabolismo , Condicionamento Operante/efeitos dos fármacos , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Proteínas Oncogênicas v-fos/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Contagem de Células/métodos , Condicionamento Operante/fisiologia , Extinção Psicológica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato Descarboxilase/metabolismo , Masculino , Mecamilamina/farmacologia , Antagonistas Nicotínicos/farmacologia , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Estatísticas não Paramétricas , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
8.
J Neurochem ; 109(2): 326-35, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19183250

RESUMO

Hypothalamic norepinephrine (NE) release regulates arterial pressure by altering sympathetic nervous system activity. Because angiotensin (Ang) (1-7) decreases hypothalamic NE release and this effect may be correlated with a diminished NE synthesis, we hypothesize that Ang-(1-7) down-regulates tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamines biosynthesis. We investigated the effect of Ang-(1-7) on centrally TH activity and expression. TH activity was evaluated by the release of tritiated water from (3)H-l-tyrosine. TH expression and phosphorylation were determined by western blot. Hypothalami from normotensive or spontaneously hypertensive rats pre-incubated with Ang-(1-7) showed a significant decrease in TH specific activity. Ang-(1-7) caused a decrease in TH phosphorylation at Ser19 and Ser40 residues. The heptapeptide induced a decrease in TH expression that was blocked by an AT(2) receptor antagonist and not by an AT(1) or Mas receptor antagonist, suggesting the involvement of AT(2) receptors. The proteasome inhibitor MG132 blocked the Ang-(1-7)-mediated TH reduction. In addition, Ang-(1-7) increased the amount of TH-ubiquitin complexes, indicating that the Ang-(1-7)-mediated TH degradation involves ubiquitin conjugation prior to proteasome degradation. We conclude that Ang-(1-7) down-regulates TH activity and expression centrally leading to a decrease in the central NE system activity.


Assuntos
Angiotensina I/fisiologia , Fragmentos de Peptídeos/fisiologia , Complexo de Endopeptidases do Proteassoma/fisiologia , Receptores de Angiotensina/fisiologia , Transdução de Sinais/fisiologia , Tirosina 3-Mono-Oxigenase/metabolismo , Ubiquitina/fisiologia , Animais , Células Cultivadas , Cavalos , Masculino , Complexo de Endopeptidases do Proteassoma/química , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ubiquitina/química
9.
Peptides ; 28(8): 1580-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17646033

RESUMO

Since angiotensin (Ang) (1-7) injected into the brain blocked Ang II pressor actions in rats made hypertensive by aortic coarctation (CH), we examined systemic and tissue angiotensin peptide levels, specifically concentrating on the hypothalamic Ang-(1-7) levels. Plasma, heart and kidney isolated from CH rats showed increased levels of Ang I, Ang II and Ang-(1-7) compared with the normotensive group, with Ang II being the predominant peptide in heart and kidney. In the hypothalamus, equimolar amounts of Ang II and Ang-(1-7) were found in the sham group, whereas only Ang-(1-7) levels increased in CH rats. We conclude that aortic coarctation activates systemic and tissue renin-angiotensin system. The increased central levels of Ang-(1-7) in the CH rats suggest a potential mitigating role of this peptide in central control of the hypertensive process.


Assuntos
Angiotensina I/metabolismo , Coartação Aórtica/complicações , Coartação Aórtica/metabolismo , Hipertensão/etiologia , Hipertensão/metabolismo , Hipotálamo/metabolismo , Fragmentos de Peptídeos/metabolismo , Angiotensina II/metabolismo , Angiotensinas/metabolismo , Animais , Rim/metabolismo , Masculino , Miocárdio/metabolismo , Ratos , Ratos Wistar , Sistema Renina-Angiotensina/fisiologia
10.
J Sep Sci ; 29(3): 405-13, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16544883

RESUMO

A new LC-ESI-MS method was developed for the determination of residues of the antibacterial tylosins A, B, C and D in honey. The procedure employed an SPE on polymeric cartridges for the isolation of tylosins from diluted honey. Chromatographic separation of the tylosins was performed on a C18 column (150 x 4.60 mm2 ID, 5 microm) using a ternary gradient made of formic acid 1% in water (solvent A), methanol (solvent B) and ACN (solvent C) as mobile phase, at 30 degrees C and at a flow rate of 0.8 mL/min. Average analyte recoveries for the studied compounds ranged from 89 to 106% in replica sets of fortified honey samples. The detection limits for the four drugs studied were between 2 and 3 microg/kg. The developed method has been applied to the analysis of tylosin residues in honey from veterinarian treated beehives fed with the technical product, which contains the four compounds and is a new candidate antibiotic to treat American foulbrood disease of honey bee colonies.


Assuntos
Antibacterianos/análise , Mel/análise , Tilosina/análise , Antibacterianos/química , Cromatografia Líquida , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Temperatura , Tilosina/química
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