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1.
Br Poult Sci ; : 1-8, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995227

RESUMO

1. The production of chicken meat has resulted in high volumes of byproducts, such as feathers, bones, skin, viscera, and feet. The structure of feathers is one of the most complex among vertebrates, with a central axis and lateral filamentary structures, providing rigidity, lightness, and flexibility. Chicken feathers are composed of proteins, lipids, and water, with the highest protein content, especially keratin, which is responsible for the material's rigidity.2. Industries still make little use of feathers, which are generally intended for the production of flour or organic fertilisers. These are low added value products, and discarded feathers can harm the environment.3. Keratin extraction techniques and resulting protein hydrolysates have been studied in chicken feathers. Acid, alkaline or enzymatic hydrolysis is the most commonly used method for obtaining molecules with functional properties such as antioxidant, antimicrobial, antihypertensive and antidiabetic activity.4. The development of keratin-based biodegradable films represents an area of interest for reducing the economic and environmental impacts caused by inappropriate disposal of feathers.

2.
Bull Entomol Res ; 111(5): 568-578, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33858528

RESUMO

The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is one of the main pests of fruit, worldwide, and the use of population suppression method with low environmental impact is an increasingly strong requirement of the consumer market. The aim of this study was to evaluate the effect of mineral and natural films on the physical-chemical properties of grapes (Vitis vinifera L.), cultivar Itália, and oviposition behaviour of C. capitata. Fruits were immersed in suspensions (100 and 200 g L-1) of mineral (kaolin Surround®WP, kaolin 607, kaolin 608, kaolin 611 and talc) and natural films (chitosan, cassava starch, potato starch and guar gum 5.0 g L-1) and distilled water (control). After drying, fruits were exposed to C. capitata pairs of males and females for 24 h in choice and non-choice tests; the number of punctures with and without eggs, eggs per fruit and behavioural response of fly to treated and untreated fruits were recorded. Results obtained in this study are promising, given the scientific evidence that films of mineral particles such as kaolin (Surround®, 607, 608 and 611) changed the firmness, luminosity, chroma and hue angle of grapes and reduced the oviposition of C. capitata. In addition, our results also showed that natural polymers do not deter C. capitata females, but rather seem to stimulate oviposition.


Assuntos
Ceratitis capitata/fisiologia , Filmes Cinematográficos , Oviposição , Vitis , Animais , Feminino , Frutas , Caulim , Masculino , Polímeros , Talco
3.
Epidemiol Infect ; 148: e198, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32892789

RESUMO

This study aimed to analyse the survival of patients admitted to Brazilian hospitals due to the COVID-19 and estimate prognostic factors. This is a retrospective, multicentre cohort study, based on data from 46 285 hospitalisations for COVID-19 in Brazil. Survival functions were calculated using the Kaplan-Meier's method. The log-rank test compared the survival functions for each variable and from that, hazard ratios (HRs) were calculated, and the proportional hazard model was used in Cox multiple regression. The smallest survival curves were the ones for patients at the age of 68 years or more, black/mixed race, illiterate, living in the countryside, dyspnoea, respiratory distress, influenza-like outbreak, O2 saturation <95%, X-ray change, length of stay in the intensive care unit (ICU), invasive ventilatory support, previous heart disease, pneumopathy, diabetes, Down's syndrome, neurological disease and kidney disease. Better survival was observed in the influenza-like outbreak and in an asthmatic patient. The multiple model for increased risk of death when they were admitted to the ICU HR 1.28, diabetes HR 1.17, neurological disease HR 1.34, kidney disease HR 1.11, heart disease HR 1.14, black or mixed race of HR 1.50, asthma HR 0.71 and pneumopathy HR 1.12. This reinforces the importance of socio-demographic and clinical factors as a prognosis for death.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/mortalidade , Pneumonia Viral/epidemiologia , Pneumonia Viral/mortalidade , Idoso , Brasil/epidemiologia , COVID-19 , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
4.
Zygote ; 26(5): 417-423, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30460886

RESUMO

SummaryThis study investigated the in vitro culture of bovine follicles included in ovarian tissue for 2 or 6 days (D2 or D6), with the addition of different concentrations of follicle-stimulating hormone (FSH) (0, 10, 50, 100 or 200 ng/ml). Data were compared for follicular development, morphological integrity and diameter of follicles and oocytes. Ovaries (n = 10) from Nelore cows (n = 5) were divided into fragments (n = 11 per ovary) and were immediately fixed in Bouin's solution (D0) or were individually cultured for 2 or 6 days in one of the described concentrations of FSH and then processed for histology. Compared with the rates of follicular development at D2 for minimal essential medium (MEM) (75.0%) and 50 ng/ml of FSH (71.1%), the best rates of follicular development at D2 were obtained with 10 (84.7%), 100 (87.5%) and 200 ng/ml of FSH (85.0%; P<0.05). After 6 days of cultivation, there were no differences among treatments regarding follicular growth. The morphological integrity of preantral follicles was better maintained by 100 ng/ml FSH for 2 and 6 days of cultivation (51.2 and 40.4%, respectively; P<0.05) than that for MEM (D2: 30.9%, D6: 20.8%), 10 (D2: 39.2%, D6: 22.8%), 50 (D2: 30.4%, D6: 28.8%) and 200 ng/ml FSH (D2: 45.2%, D6: 36.8%). FSH at 100 ng/ml provided the highest mean diameter averages: 34.5±10.8 µm at D2 and 33.2±12.5 µm at D6 (P<0.05). We concluded that the medium supplemented with 100 ng/ml FSH during in vitro culture provided appropriate conditions for the development and morphological integrity of preantral follicles in cattle.


Assuntos
Hormônio Foliculoestimulante/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Animais , Bovinos , Relação Dose-Resposta a Droga , Feminino , Hormônio Foliculoestimulante/farmacologia , Folículo Ovariano/citologia , Técnicas de Cultura de Tecidos
5.
J Fish Biol ; 92(4): 1051-1064, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29465800

RESUMO

The expression pattern of genes coding for enzymes of the retinoic acid (RA) synthetic and degradation pathways was characterized in adult female zebrafish Danio rerio. Females were conditioned until maturation and post-spawn expression dynamics were determined. A striking upregulation of cyp26b1, but not cyp26a1, was observed following egg deposition, decreasing to initial levels during recovery. A similar, yet lower, fluctuation was observed for aldh1a2 and rdh10a, the enzymes participating in the two-step RA biosynthesis cascade. The present work highlights the dynamics of the adult D. rerio oogenesis and uncovers novel, yet elusive, metabolic contributors. Possible compartmentalized roles for the different gene paralogue isoforms are discussed.


Assuntos
Gônadas/metabolismo , Oogênese , Retinal Desidrogenase/metabolismo , Tretinoína/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Feminino , Retinal Desidrogenase/genética , Ácido Retinoico 4 Hidroxilase/genética , Ácido Retinoico 4 Hidroxilase/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
6.
J Toxicol Environ Health A ; 80(9): 465-476, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28682217

RESUMO

Nuclear receptors (NR) are involved in the regulation of several metabolic processes and it is well known that these constituents may be modulated by different chemicals classes, including pharmaceuticals that may activate or antagonize NR. In mammals, some pharmaceuticals modulate the transcription of pregnane X receptor, Pxr, peroxisome proliferator activated receptor, Ppars, and aryl hydrocarbon receptor, Ahr, affecting mRNA expression of genes belonging to various regulatory pathways, including lipid metabolism and detoxification mechanisms. The aim of this study was to determine the effects of simvastatin (SIM), an anticholesterolemic drug, on selected NR and AhR mRNA transcription levels during zebrafish early development. Embryos were collected at different development stages (0, 2, 6, 14, 24, 48, and 72 hr post fertilization (hpf)) and mRNA of all target NR was detected at all time points. Embryos (1 and 24 hpf) were exposed to different concentrations of SIM (5 or 50 µg/L) in two differing assays with varying exposure times (2 or 80 hr). The transcription levels of ahr2, raraa, rarab, rarga, pparαa, pparß1, pparγ, pxr, rxraa, rxrab, rxrbb, rxrga, rxrgb, as well as levels of cholesterol (Chol) were measured after exposure. SIM exerted no marked effect on Chol levels, and depending upon exposure duration mRNA levels of NR and AhR either increased or decreased. After 2 hr SIM treatment in 24 hpf embryos, transcription of ppars, pxr, and ahr was up-regulated, while after 80 hr mRNA levels of pxr and ahr were decreased with no marked changes in ppars. Data demonstrate that SIM produced alterations in gene expression of NR which are involved in varying physiological functions and that may disturb regulation of different physiological processes which might impair fish survival and ecosystems regeneration.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Sinvastatina/farmacologia , Peixe-Zebra/genética , Animais
7.
Ecotoxicol Environ Saf ; 136: 14-23, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27810576

RESUMO

Certain ATP binding cassette (ABC) transporter proteins, such as zebrafish Abcb4, are efflux pumps acting as a cellular defence against a wide range of different, potentially toxic chemical compounds thus mediating so called multixenobiotic resistance (MXR). Certain chemicals target MXR proteins and, as so called chemosensitisers, inhibit the activity of these proteins thus increasing the toxicity of other chemicals that would normally be effluxed. In this study 14 pharmaceuticals and personal care products (PPCPs) that are being increasingly detected in aquatic systems, were assessed for interference with the MXR system of zebrafish (Danio rerio). Concentration dependent effects of test compounds were recorded with the dye accumulation assay using zebrafish embryos and in ATPase assays with recombinant zebrafish Abcb4. In the dye accumulation assay embryos at 24h post fertilisation (hpf) were exposed to 8µm rhodamine 123 along with test compounds for 2h. The rhodamine 123 tissue levels upon the exposure served as a measure for MXR transporter efflux activity of the embryo (low rhodamine levels - high activity; high levels - low activity). The known ABC protein inhibitors MK571, vinblastine and verapamil served as positive controls. All tested PPCPs affected rhodamine 123 accumulation in embryos. For seven compounds rhodamine tissue levels were either both decreased and increased depending on the compound concentration indicating both stimulation and inhibition of rhodamine 123 efflux by those compounds, only increased (inhibition, six compounds) or only decreased (stimulation, one compound). Recombinant zebrafish Abcb4 was obtained with the baculovirus expression system and PPCPs were tested for stimulation/inhibition of basal transporter ATPase activity and for inhibition of the transporter ATPase activity stimulated with verapamil. Eight of the tested PPCPs showed effects on Abcb4 ATPase activity indicating that their effects in the dye accumulation assay may have indeed resulted from interference with Abcb4-mediated rhodamine 123 efflux. Slight stimulatory effects were found for musk xylene, nerol, isoeugenol, α-amylcinnamaldehyde, α-hexylcinnamaldehyde and simvastatin indicating Abcb4 substrate/competitive inhibitor properties of those compounds. Likewise, decreases of the verapamil-stimulated Abcb4 ATPase activity by diclofenac and fluoxetine may indicate competitive transporter inhibition. Sertraline inhibited the basal and verapamil-stimulated Abcb4 ATPase activities suggesting its property as non-competitive Abcb4 inhibitor. Taken together, our finding that chemically diverse PPCPs interfere with MXR efflux activity of zebrafish indicates that (1) efflux transporters may influence bioaccumulation of many PPCPs in fish and that (2) many PPCPs may act as chemosensitisers. Furthermore, it appears that interference of PPCPs with efflux activity in zebrafish embryos is not only from effects on Abcb4 but also on other efflux transporter subtypes.


Assuntos
Transportadores de Cassetes de Ligação de ATP/efeitos dos fármacos , Cosméticos/farmacologia , Preparações Farmacêuticas , Acroleína/análogos & derivados , Acroleína/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Bioensaio , Transporte Biológico/efeitos dos fármacos , Resistência a Medicamentos , Rodaminas/metabolismo , Verapamil/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo
8.
Phys Chem Chem Phys ; 18(39): 27507-27520, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27711471

RESUMO

The influence of solvent type on the solution thermodynamics, nucleation-kinetics and crystal growth of alpha para-aminobenzoic acid (PABA) crystallising from supersaturated ethanol, acetonitrile and water solutions, is examined using poly-thermal analysis of the metastable zone width. Application of a recently proposed model for analysis of crystallisation kinetics (J. Cryst. Growth, 2010, 312, 698-704) indicates a solvent and concentration dependence of the nucleation mechanism and key nucleation parameters for the alpha form of PABA. The mechanism of nucleation is found to change from instantaneous to progressive with decreasing concentration and also when changing the solvent from ethanol to acetonitrile to water. The dependence of the nucleation mechanism is correlated to the kinetic component of the nucleation rate through calculated values of instantaneously nucleated crystallites, which increase from 1.40 × 109 m-3 in ethanol to 1.08 × 1010 m-3 in acetonitrile to 2.58 × 1010 m-3 in water. This in combination with low calculated number concentrations of interfacial tension between 1.13 and 2.71 mJ m-2, supports the conclusion that the kinetic component of the nucleation rate is more limiting when crystallising PABA from ethanol solutions in comparison to water solutions. This finding is further supported by molecular dynamics simulations of the solvation free energy of PABA, which is found to be greatest in water, -42.4 kJ mol-1 and lowest in ethanol, -58.5 kJ mol-1.

9.
Gen Comp Endocrinol ; 225: 142-148, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26597622

RESUMO

Germ cell commitment and meiosis initiation are among the multitude of physiological roles of retinoic acid (RA) in vertebrates. Acting via receptor-mediated transcription, RA induces the expression of meiotic factors, triggering meiosis. Contrasting with vertebrates, invertebrate RA metabolism is scarcely understood. Still, some physiological processes appear to be conserved. Here we set to evaluate the role of retinoids in the gonad maturation process of the marine gastropod Patella vulgata. We found that retinoid concentration in gonadal tissue, namely RA, varies between breeding and resting specimens, with maxima attained in the latter. Additionally, we isolated and quantified the expression of both the retinoic acid receptor (RAR) and the retinoid X receptor (RXR) in gonads. In view of the stability of retinoid receptor expression, we suggest that the balance of RA levels operates through the enzymatic control of synthetic and catabolic processes. Overall, the reported data are supportive for a developmental role of RA during gonadal maturation in P. vulgata, which should be addressed in other protostome lineages.


Assuntos
Gastrópodes/metabolismo , Gônadas/metabolismo , Receptores do Ácido Retinoico/metabolismo , Receptores X de Retinoides/metabolismo , Retinoides/metabolismo , Animais , Proteínas de Transporte , Expressão Gênica , Reprodução/fisiologia , Tretinoína/metabolismo
10.
Genet Mol Res ; 14(4): 18936-44, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26782543

RESUMO

Type 1 diabetes mellitus (T1D) is a complex disorder characterized by an autoimmune response against human pancreatic beta-cells. Patients with T1D can also develop a response toward one or more other factors, such as in autoimmune thyroiditis (AITD) and celiac disease (CD). In the presence of T1D + AITD, the patient is diagnosed with autoimmune polyglandular syndrome type III (APSIII); patients with APSIII may also present with CD. These diseases have a strong genetic component and share many susceptibility genes, suggesting potentially overlapping pathogenic pathways. Polymorphisms in the TNF-α(rs1800629), CTLA-4 (rs231775), and PTPN22 (rs2476601) genes have been previous associated with T1D; however, there is no consensus regarding their role in T1D and scarce literature focusing on AIDT and/or CD. Thus, we analyzed these genetic variants in 205 Northeast Brazilian patients with T1D and with/without AITD and/or CD, and in 308 healthy controls. The PTPN22 gene variants were associated with T1D susceptibility and APSIII [odds ratio (OR) = 2.57 and 2.77, respectively]. CTLA4 rs231775 and TNF-αrs1800629 were not associated with T1D onset in the Brazilian population. However, when comparing APSIII individuals in the T1D only group, we observed an association of the TNF-αSNP in the allelic (P = 0.0442; OR = 0.44) and dominant models (P = 0.0387; OR = 0.40). This study reinforces the importance of CTLA-4 and other variants in unraveling the pathogenic mechanisms of T1D in different populations and in understanding their relationships with the development of other T1D-related autoimmune diseases.


Assuntos
Antígeno CTLA-4/genética , Diabetes Mellitus Tipo 1/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Fator de Necrose Tumoral alfa/genética , Adolescente , Adulto , Idade de Início , Brasil , Criança , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Adulto Jovem
11.
Genet Mol Res ; 14(4): 17730-8, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26782418

RESUMO

Type 1 diabetes mellitus (T1D) is an organ-specific autoimmune disease characterized by T-cell mediated self-destruction of insulin-producing ß cells in the pancreas. T1D patients are prone to develop other glandular autoimmune disorders, such as autoimmune thyroid disease that occurs simultaneously with autoimmune polyglandular syndrome type III (APSIII). Signal transducer and activator of transcription 4 (STAT4) is a well-known regulator of proinflammatory cytokines, and interferon-induced with helicase C domain 1 (IFIH1) is activated in the interferon type I response. Both genes have been examined separately in autoimmune diseases and, in this study, we assessed their joint role in T1D and APSIII. We conducted a case-control study, enrolling 173 T1D patients and 191 healthy controls from northeastern Brazil, to assess the distribution of the rs7574865 and rs3024839 SNPs in STAT4 and the rs3747517 and rs1990760 SNPs in IFIH1 in T1D and APSIII patients. Additionally, we conducted a meta-analysis with the rs7574865 SNP in STAT4 (1392 T1D patients and 1629 controls) and the rs1990760 SNP in IFIH1 (25092 T1D patients and 28544 controls) to examine their association with T1D. Distribution of STAT4 and IFIH1 allelic frequencies did not show statistically significant differences between T1D patients and controls in our study population; however, the meta-analysis indicated that SNPs in STAT4 and IFIH1 are associated with T1D worldwide. Our findings indicate that although STAT4 and IFIH1 SNPs are not associated with T1D in a Brazilian population, they might play a role in susceptibility to T1D on a larger worldwide scale.


Assuntos
RNA Helicases DEAD-box/genética , Diabetes Mellitus Tipo 1/genética , Poliendocrinopatias Autoimunes/genética , Fator de Transcrição STAT4/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/patologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Helicase IFIH1 Induzida por Interferon , Masculino , Pessoa de Meia-Idade , Poliendocrinopatias Autoimunes/complicações , Poliendocrinopatias Autoimunes/patologia , Polimorfismo de Nucleotídeo Único , Transdução de Sinais/genética
12.
J Environ Manage ; 164: 151-60, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26363977

RESUMO

Solid waste disposal sites (SWDS) - especially landfills - are a significant source of methane, a greenhouse gas. Although having the potential to be captured and used as a fuel, most of the methane formed in SWDS is emitted to the atmosphere, mainly in developing countries. Methane emissions have to be estimated in national inventories. To help this task the Intergovernmental Panel on Climate Change (IPCC) has published three sets of guidelines. In addition, the Kyoto Protocol established the Clean Development Mechanism (CDM) to assist the developed countries to offset their own greenhouse gas emissions by assisting other countries to achieve sustainable development while reducing emissions. Based on methodologies provided by the IPCC regarding SWDS, the CDM Executive Board has issued a tool to be used by project developers for estimating baseline methane emissions in their project activities - on burning biogas from landfills or on preventing biomass to be landfilled and so avoiding methane emissions. Some inconsistencies in the first two IPCC guidelines have already been pointed out in an Annex of IPCC latest edition, although with hidden details. The CDM tool uses a model for methane estimation that takes on board parameters, factors and assumptions provided in the latest IPCC guidelines, while using in its core equation the one of the second IPCC edition with its shortcoming as well as allowing a misunderstanding of the time variable. Consequences of wrong ex-ante estimation of baseline emissions regarding CDM project activities can be of economical or environmental type. Example of the first type is the overestimation of 18% in an actual project on biogas from landfill in Brazil that harms its developers; of the second type, the overestimation of 35% in a project preventing municipal solid waste from being landfilled in China, which harms the environment, not for the project per se but for the undue generated carbon credits. In a simulated landfill - the same amount of waste for 20 years -, the error would be an overestimation of 25% if the CDM project activity starts from the very first year or an underestimation of 15% if it starts just after the landfill closure. Therefore, a correction in the tool to calculate emissions from landfills as adopted by the CDM Executive Board is needed. Moreover, in countries not using the latest IPCC guidelines, which provides clear formulas to prevent misunderstandings, inventory compilers can also benefit from this paper by having more accurate results in national GHG inventories related to solid waste disposal, especially when increasing amounts of waste are landfilled, which is the case of the developing countries.


Assuntos
Metano/análise , Modelos Teóricos , Eliminação de Resíduos/métodos , Instalações de Eliminação de Resíduos , Biocombustíveis , Brasil , China , Mudança Climática , Conservação dos Recursos Naturais , Países em Desenvolvimento , Efeito Estufa , Resíduos Sólidos
13.
Gen Comp Endocrinol ; 208: 134-45, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25132059

RESUMO

Recent genomic and biochemical evidence in invertebrate species pushes back the origin of the retinoid metabolic and signaling modules to the last common ancestor of all bilaterians. However, the evolution of retinoid pathways are far from fully understood. In the majority of non-chordate invertebrate lineages, the ongoing functional characterization of retinoid-related genes (metabolism and signaling pathways), as well as the characterization of the endogenous retinoid content (precursors and active retinoids), is still incomplete. Despite limited, the available data supports the presence of biologically active retinoid pathways in invertebrates. Yet, the mechanisms controlling the spatial and temporal distribution of retinoids as well as their physiological significance share similarities and differences with vertebrates. For instance, retinol storage in the form of retinyl esters, a key feature for the maintenance of retinoid homeostatic balance in vertebrates, was only recently demonstrated in some mollusk species, suggesting that such ability is older than previously anticipated. In contrast, the enzymatic repertoire involved in this process is probably unlike that of vertebrates. The suggested ancestry of active retinoid pathways implies that many more metazoan species might be potential targets for endocrine disrupting chemicals. Here, we review the current knowledge about the occurrence and functionality of retinoid metabolic and signaling pathways in invertebrate lineages, paying special attention to the evolutionary origin of retinoid storage mechanisms. Additionally, we summarize existing information on the endocrine disruption of invertebrate retinoid modules by environmental chemicals. Research priorities in the field are highlighted.


Assuntos
Evolução Biológica , Disruptores Endócrinos/metabolismo , Invertebrados/metabolismo , Retinoides/metabolismo , Animais , Transdução de Sinais , Vertebrados/metabolismo
14.
J Toxicol Environ Health A ; 77(20): 1210-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25208661

RESUMO

Despite the recent focus on hazardous and noxious substances (HNS) spills preparedness and responses, much remains to be done regarding the threat posed by HNS spills on marine biota. Among the identified priority HNS, p-xylene was selected to conduct ecotoxicological assays. The aim of this study was to assess the performance of the amphipod Gammarus locusta under acute and chronic exposure to p-xylene simulating conditions of a spill incident. In the acute exposure (96 h) the p-xylene LC50 was estimated. In the chronic bioassay (36 d), an integration of organism-level endpoints (survival, growth rate, and sex ratio) with biochemical markers indicative of oxidative stress including catalase (CAT), glutathione S-transferase (GST), and superoxide dismutase (SOD) activities and lipid peroxidation (LPO) levels was determined. The aim was to increase the xylene ecotoxicological database and better predict its impact in aquatic environments. p-Xylene induced several chronic toxicity effects in G. locusta. Significant alterations in antioxidant enzymes and lipid peroxidation levels as well as growth rate and biased sex-ratio were observed. p-Xylene significantly affected the activities of CAT, SOD, and GST in G. locusta and produced oxidative damage by increasing levels of LPO in males. Further, impacts in key ecological endpoints, that is, growth and sex ratio, were noted that might be indicative of potential effects at the population level in a spill scenario. The present data may be useful to assist relevant bodies in preparedness and response to HNS spills.


Assuntos
Anfípodes/efeitos dos fármacos , Organismos Aquáticos/efeitos dos fármacos , Exposição Ambiental/análise , Xilenos/toxicidade , Animais , Organismos Aquáticos/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Determinação de Ponto Final , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Poluentes Químicos da Água/toxicidade
15.
Mar Pollut Bull ; 199: 115974, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176164

RESUMO

Deep-sea hydrothermal vents host unique ecosystems but face risks of incidents with Hazardous and Noxious Substances (HNS) along busy shipping lanes such as the transatlantic route. We developed an Ecopath with Ecosim (EwE) model of the Menez Gwen (MG) vent field (MG-EwE) (Mid-Atlantic Ridge) to simulate ecosystem effects of potential accidental spills of four different HNS, using a semi-Lagrangian Dispersion Model (sLDM) coupled with the Regional Ocean Modelling System (ROMS) calibrated for the study area. Food web modelling revealed a simplified trophic structure with low energy efficiency. The MG ecosystem was vulnerable to disruptions caused by all tested HNS, yet it revealed some long-term resilience. Understanding these impacts is vital for enhancing Spill Prevention, Control, and Countermeasure plans (SPCC) in remote marine areas and developing tools to assess stressors effects on these invaluable habitats.


Assuntos
Ecossistema , Fontes Hidrotermais , Substâncias Perigosas , Cadeia Alimentar , Acidentes
16.
Biometals ; 26(6): 1051-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24179092

RESUMO

Hepcidin is an antimicrobial peptide hormone that plays a central role in the metabolism of iron and its expression in the liver can be induced through two major pathways: the inflammatory pathway, mainly via IL-6; and the iron-sensing pathway, mediated by BMP-6. GATA-proteins are group of evolutionary conserved transcriptional regulators that bind to the consensus motif-WGATAR-in the promoter region. In hepatoma cells, GATA-proteins 4 and 6 in conjunction with the co-factor friend of GATA (FOG) were shown to modulate the transcription of HAMP. However, it is unclear as to which of the GATA-proteins drive the expression of HAMP in vivo. In this study, using in vitro and in vivo approaches, we investigated the relevance of GATA and FOG proteins in the expression of hepcidin following treatment with IL-6 and BMP-6. We found that treatment of Huh7 cells with either IL-6 or BMP-6 increased the HAMP promoter activity. The HAMP promoter activity following treatment with IL-6 or BMP-6 was further increased by co-transfection of the promoter with GATA proteins 4 and 6. However, co-transfection of the HAMP promoter with FOG proteins 1 or 2 repressed the promoter response to treatments with either IL-6 or BMP-6. The effects of both GATA and FOG proteins on the promoter activity in response to IL-6 or BMP-6 treatment were abrogated by mutation of the GATA response element-TTATCT-in the HAMP promoter region -103/-98. In vivo, treatment of mice with lipopolysaccharide led to a transient increase of Gata-6 expression in the liver that was positively correlated with the expression of hepcidin. Our results indicate that during inflammation GATA-6 is up-regulated in concert with hepcidin while GATA-4 and FOG (1 and 2) are repressed.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição GATA6/metabolismo , Hepatócitos/efeitos dos fármacos , Hepcidinas/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Proteína Morfogenética Óssea 6/farmacologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Feminino , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Fator de Transcrição GATA6/genética , Regulação da Expressão Gênica , Hepatócitos/citologia , Hepatócitos/metabolismo , Hepcidinas/agonistas , Hepcidinas/genética , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Interleucina-6/farmacologia , Lipopolissacarídeos , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Transcrição/genética , Transcrição Gênica
17.
Toxicol Mech Methods ; 23(8): 591-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23718563

RESUMO

Abstract The recent advances in molecular biology techniques have prompted the use of vitellogenin (VTG) gene expression as a sensitive and reliable indicator of estrogenic chemicals (EC) exposure. However, data on the dynamic response of the different VTGs genes upon EC exposure is still poorly understood, particularly in sentinel fish species used in field monitoring studies. Hence, the present study aimed at developing a sensitive real-time PCR assay for determining the response of VTG I and II in the recently proposed marine sentinel species Lipophrys pholis upon exposure to the model EC 17α-ethinylestradiol (EE2). The findings of the laboratory study indicate that L. pholis VTG I proved to be not only more inducible but also more sensitive to EE2 exposure than VTG II, for the same range of concentrations. In fact, VTG I gene induction was 475-fold higher than VTG II at 15 ng/L EE2, and 13-fold at 5 ng/L EE2. Overall, the findings of the present study indicate that in the field, expression of VTG I in L. pholis should be preferentially used in the screening of EC exposure because of its higher sensitivity. Furthermore, the present study favors L. pholis integration in monitoring programs associated with EC's pollution within the European water policy legislation.


Assuntos
Peixes/genética , Fígado/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Vitelogeninas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
18.
Braz J Biol ; 83: e265435, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700592

RESUMO

Sapindus saponaria L. (Sapindaceae) is a pioneer species used in programs to recover degraded areas. The trees also assist in the pest control of some insects due to the composition of saponins on their leaves. In addition, these chemical components are important to pharmaceutical product production. The objective was to evaluate the impact of spatial distribution, indices and ecological relationship of arthropods on S. saponaria leaves to preserve the balance of biodiversity. Aggregated distribution of arthropods was observed; the numbers of phytophagous arthropods were higher on the adaxial leaf face than on the abaxial part. Only Aleyrodidae (Hemiptera) had a higher presence on the abaxial leaf face of S. saponaria saplings. Abundance, diversity, and species richness of natural enemies correlated positively with phytophagous and pollinators insects. On the other hand, the number of Lyriomyza sp. mines correlated negatively with Pseudomyrmex termitarius (Smith) (Hymenoptera: Formicidae). All this information can assist and guide integrated pest management programs.


Assuntos
Artrópodes , Hemípteros , Sapindaceae , Sapindus , Saponaria , Animais , Insetos , Biodiversidade
19.
Meat Sci ; 204: 109286, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37494740

RESUMO

We aimed to evaluate the impact of nutrient supplementation of beef female calves at pre-weaning on adipogenic determination. Thirty-four female calves were assigned to two experimental treatments: Control (CON, n = 17), where animals were supplemented only with mineral mixture; Supplemented (SUP, n = 17), where animals received energy-protein supplement containing minerals (5 g/kg of BW per day) of their body weight. Animals were supplemented from 100 to 250 days of age, and muscle samples were biopsied at the end of the supplementation period. Regarding the performance variables, there were no differences between treatments for initial body weight (P = 0.75). The final body weight (P = 0.07), average daily gain (P = 0.07), rib eye area (P = 0.03), and rib fat thickness (P = 0.08) were greater in SUP female calves compared with CON treatment. The number of fibro-adipogenic progenitor cells (P = 0.69) did not differ between treatments, while a greater number of intramuscular pre-adipocytes were observed in SUP than CON female calves (P = 0.01). The expression of miRNA-4429 (P = 0.20) did not differ between treatments, while the expression of miRNA-129-5p (P = 0.09) and miRNA-129-2-3p (P = 0.05) was greater in CON than SUP female calves. Our results suggest that nutrient supplementation at early postnatal stages of development enhances the commitment of fibro-adipogenic progenitor cells into the adipogenic lineages allowing to an increase in intramuscular fat deposition potential of the animals later in life.


Assuntos
Dieta , MicroRNAs , Bovinos , Animais , Feminino , Dieta/veterinária , Desmame , Ração Animal/análise , Suplementos Nutricionais , Peso Corporal , Nutrientes
20.
Braz J Med Biol Res ; 56: e12533, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37585913

RESUMO

L-Arginine and chronic exercise reduce oxidative stress. However, it is unclear how they affect cardiomyocytes during cardiovascular disease (CVD) development. The aim of this research was to investigate the possible effects of L-arginine supplementation and aerobic training on systemic oxidative stress and their consequences on cardiomyocytes during cardiometabolic disease onset caused by excess fructose. Wistar rats were allocated into four groups: control (C), fructose (F, 10% fructose in water), fructose training (FT; moderate running, 50-70% of the maximal velocity), and fructose arginine (FA; 880 mg/kg/day). Fructose was given for two weeks and fructose plus treatments for the subsequent eight weeks. Body composition, blood glucose, insulin, lipid profile, lipid peroxidation, nitrite, metalloproteinase-2 (MMP-2) activity, left ventricle histological changes, microRNA-126, -195, and -146, eNOS, p-eNOS, and TNF-α expressions were analyzed. Higher abdominal fat mass, triacylglycerol level, and insulin level were observed in the F group, and both treatments reversed these alterations. Myocardial vascularization was impaired in fructose-fed groups, except in FT. Cardiomyocyte hypertrophy was observed in all fructose-fed groups. TNF-α levels were higher in fructose-fed groups than in the C group, and p-eNOS levels were higher in the FA than in the C and F groups. Lipid peroxidation was higher in the F group than in the FT and C groups. During CVD onset, moderate aerobic exercise reduced lipid peroxidation, and both training and L-arginine prevented metabolic changes caused by excessive fructose. Myocardial vascularization was impaired by fructose, and cardiomyocyte hypertrophy appeared to be influenced by pro-inflammatory and oxidative environments.


Assuntos
Doenças Cardiovasculares , MicroRNAs , Ratos , Animais , Doenças Cardiovasculares/metabolismo , Miócitos Cardíacos/metabolismo , Ratos Wistar , Fator de Necrose Tumoral alfa/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo , Arginina/farmacologia , Arginina/metabolismo , Insulina , Frutose/metabolismo , Frutose/farmacologia , Suplementos Nutricionais , Hipertrofia/metabolismo , MicroRNAs/metabolismo
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