RESUMO
In this work, an accurate analytical method was developed for the simultaneous analysis of twenty-seven antimicrobials (AMs) in earthworms using liquid chromatography coupled to a triple quadrupole mass spectrometry detector (UHPLC-MS/MS). Adequate apparent recoveries (80-120 %) and limits of quantification (LOQ) (1 µg·kg-1 - 10 µg·kg-1) were obtained, with the exception of norfloxacin (34 µg·kg-1). The method was applied to evaluate the accumulation of sulfamethazine (SMZ) and tetracycline (TC) in earthworms after performing OECD-207 toxicity test, in which Eisenia fetida (E. fetida) organisms were exposed to soils spiked with 10 mg·kg-1, 100 mg·kg-1 or 1000 mg·kg-1 of SMZ and TC, individually. The results confirmed the bioaccumulation of both AMs in the organisms, showing a greater tendency to accumulate SMZ since higher bioconcentration factor values were obtained for this compound at the exposure concentrations tested. In addition, the degradation of both AMs in both matrices, soils and earthworms was studied using liquid chromatography coupled to a q-Orbitrap high resolution mass spectrometry detector. Thirteen transformation products (TPs) were successfully identified, eight of them being identified for the first time in soil/earthworm (such as 4-Amino-3-chloro-n-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide or 4-(dimethylamino)-1,11,12a-trihydroxy-6,6-dimethyl-3,7,10,12-tetraoxo-3,4,4a,5,5a,6,7,10,12,12a-decahydrotetracene-2-carboxamide, among others) and their formation/degradation trend over time was also studied. Regarding the biological effects, only SMZ caused changes in earthworm growth, evidenced by weight loss in earthworms exposed to concentrations of 100 mg·kg-1 and 1000 mg·kg-1. Riboflavin decreased at all concentrations of SMZ, as well as at the highest concentration of TC. This indicates that these antibiotics can potentially alter the immune system of E. fetida. This research represents a significant advance in improving our knowledge about the contamination of soil by AM over time. It investigates the various ways in which earthworms are exposed to AMs, either by skin contact or ingestion. Furthermore, it explores how these substances accumulate in earthworms, the processes by which earthworms break them down or metabolise them, as well as the resulting TPs. Finally, it examines the potential effects of these substances on the environment.
Assuntos
Anti-Infecciosos , Oligoquetos , Poluentes do Solo , Animais , Oligoquetos/metabolismo , Espectrometria de Massas em Tandem , Poluentes do Solo/análise , Anti-Infecciosos/toxicidade , Anti-Infecciosos/metabolismo , Sulfametazina/análise , Antibacterianos/farmacologia , Solo/química , Tetraciclina/análiseRESUMO
Soil contamination by antibiotics is a global issue of great concern that contributes to the rise of bacterial antibiotic resistance and can have toxic effects on non-target organisms. This study evaluated the variations of molecular, cellular, and histological parameters in Eisenia fetida earthworms exposed to sulfamethazine (SMZ) and tetracycline (TC), two antibiotics commonly found in agricultural soils. The earthworms were exposed for 14â¯days to a series of concentrations (0, 10, 100, and 1000â¯mg/kg) of both antibiotics. SMZ and TC did not affect the survival of E. fetida, however, other effects at different levels of biological complexity were detected. The two highest concentrations of SMZ reduced the viability of coelomocytes. At the highest TC concentration, there was a noticeable decline in cell viability, acetylcholinesterase activity (neurotoxicity), and the relative presence of mucopolysaccharides in the epidermis (mucous production). Glutathione S-transferase activity decreased in all TC treatments and at the highest SMZ concentration. However, levels of malondialdehyde and protein carbonyls did not change, suggesting an absence of oxidative stress. Tetracycline was neurotoxic to E. fetida and changed the integrity of the epidermis. Both antibiotics altered the intestinal microbiota of E. fetida, leading to a reduction in the relative abundance of bacteria from the phyla Proteobacteria and Bacteroidetes, while causing an increase in the phylum Actinobacteroidota. All observed changes indicate that both SMZ and TC can disrupt the earthworms' immune system and gut microbiome, while fostering the growth of bacteria that harbour antibiotic resistance genes. Finally, both antibiotics exerted additional metabolic and physiological effects that increased the vulnerability of E. fetida to pathogens.
RESUMO
Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.
Assuntos
Anidrases Carbônicas , Tartarugas , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Anidrases Carbônicas/metabolismo , Catalase/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glicogênio/metabolismo , Nitrogênio/metabolismo , Oxigênio/metabolismo , Piruvato Carboxilase/metabolismo , RNA/metabolismo , Tartarugas/metabolismoRESUMO
Members of the ADAM family (membrane proteins with a disintegrin and metalloprotease domain) have been implicated in several cell-interactive events, including cell-cell fusion. Recent evidence implicates three ADAMs, fertilin-alpha, fertilin-beta, and meltrin-alpha, in sperm-egg fusion and myoblast fusion. In light of the large number and wide tissue distribution of the ADAMs, they may also participate in other cell-cell fusion events. As ADAMs are also found in both vertebrates and invertebrates, some features of cell-cell fusion reactions may be conserved throughout the animal kingdom.
Assuntos
Fusão Celular , Glicoproteínas de Membrana/metabolismo , Metaloendopeptidases/metabolismo , Sequência de Aminoácidos , Animais , Feminino , Masculino , Dados de Sequência Molecular , Interações Espermatozoide-ÓvuloRESUMO
This work describes the new facility for applied nuclear physics at the University of Sao Paulo, mainly for irradiation of electronic devices. It is a setup composed of a quadrupole doublet for beam focusing/defocusing plus multiple scattering through gold foils to produce low intensity, large-area, and high-uniformity heavy-ion beams from 1H to 107Ag. Beam intensities can be easily adjusted from 102 particles cm2/s to hundreds of nA for an area as large as 2.0 cm2 and uniformity better than 90%. Its irradiation chamber has a high-precision motorized stage, and the system is controlled by a LabViewTM environment, allowing measurement automation. Design considerations and examples of use are presented.
RESUMO
Most transformed cells have lost anchorage and serum dependence for growth and survival. Previously, we established that when serum is absent, fibronectin survival signals transduced by focal adhesion kinase (FAK), suppress p53-regulated apoptosis in primary fibroblasts and endothelial cells (Ilic et al. 1998. J. Cell Biol. 143:547-560). The present goals are to identify survival sequences in FAK and signaling molecules downstream of FAK required for anchorage-dependent survival of primary fibroblasts. We report that binding of the SH3 domain of p130Cas to proline-rich region 1 of FAK is required to support survival of fibroblasts on fibronectin when serum is withdrawn. The FAK-p130Cas complex activates c-Jun NH2-terminal kinase (JNK) via a Ras/Rac1/Pak1/MAPK kinase 4 (MKK4) pathway. Activated (phospho-) JNK colocalizes with FAK in focal adhesions of fibroblasts cultured on fibronectin, which supports their survival, but not in fibroblasts cultured on collagen, which does not. Cells often survive in the absence of extracellular matrix if serum factors are provided. In that case, we confirm work of others that survival signals are transduced by FAK, phosphatidylinositol 3'-kinase (PI3-kinase), and Akt/protein kinase B (PKB). However, when serum is absent, PI3-kinase and Akt/PKB are not involved in the fibronectin-FAK-JNK survival pathway documented herein. Thus, survival signals from extracellular matrix and serum are transduced by FAK via two distinct pathways.
Assuntos
Adesão Celular , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases/metabolismo , Proteínas , Animais , Sobrevivência Celular , Meios de Cultura Livres de Soro , Fibroblastos , Proteína-Tirosina Quinases de Adesão Focal , Imuno-Histoquímica , Proteínas Quinases JNK Ativadas por Mitógeno , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Coelhos , Proteína p130 Retinoblastoma-Like , Transdução de Sinais , Transfecção , Domínios de Homologia de srcRESUMO
In many malignant cells, both the anchorage requirement for survival and the function of the p53 tumor suppressor gene are subverted. These effects are consistent with the hypothesis that survival signals from extracellular matrix (ECM) suppress a p53-regulated cell death pathway. We report that survival signals from fibronectin are transduced by the focal adhesion kinase (FAK). If FAK or the correct ECM is absent, cells enter apoptosis through a p53-dependent pathway activated by protein kinase C lambda/iota and cytosolic phospholipase A2. This pathway is suppressible by dominant-negative p53 and Bcl2 but not CrmA. Upon inactivation of p53, cells survive even if they lack matrix signals or FAK. This is the first report that p53 monitors survival signals from ECM/FAK in anchorage- dependent cells.
Assuntos
Apoptose/fisiologia , Moléculas de Adesão Celular/metabolismo , Matriz Extracelular/enzimologia , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Anexinas/metabolismo , Proteínas Sanguíneas/farmacologia , Caspases/química , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Meios de Cultura Livres de Soro/farmacologia , Endotélio/citologia , Matriz Extracelular/química , Fibroblastos/química , Fibroblastos/citologia , Fibroblastos/enzimologia , Fibronectinas/metabolismo , Proteína-Tirosina Quinases de Adesão Focal , Proteínas de Fluorescência Verde , Marcação In Situ das Extremidades Cortadas , Indicadores e Reagentes , Isoenzimas/metabolismo , Proteínas Luminescentes , Fosfolipases A/metabolismo , Fosfolipases A2 , Proteína Quinase C/metabolismo , Estrutura Terciária de Proteína , Coelhos , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/citologiaRESUMO
Integrins can exist in different functional states with low or high binding capacity for particular ligands. We previously provided evidence that the integrin alpha6beta1, on mouse eggs and on alpha6-transfected cells, interacted with the disintegrin domain of the sperm surface protein ADAM 2 (fertilin beta). In the present study we tested the hypothesis that different states of alpha6beta1 interact with fertilin and laminin, an extracellular matrix ligand for alpha6beta1. Using alpha6-transfected cells we found that treatments (e.g., with phorbol myristate acetate or MnCl2) that increased adhesion to laminin inhibited sperm binding. Conversely, treatments that inhibited laminin adhesion increased sperm binding. Next, we compared the ability of fluorescent beads coated with either fertilin beta or with the laminin E8 fragment to bind to eggs. In Ca2+-containing media, fertilin beta beads bound to eggs via an interaction mediated by the disintegrin loop of fertilin beta and by the alpha6 integrin subunit. In Ca2+-containing media, laminin E8 beads did not bind to eggs. Treatment of eggs with phorbol myristate acetate or with the actin disrupting agent, latrunculin A, inhibited fertilin bead binding, but did not induce laminin E8 bead binding. Treatment of eggs with Mn2+ dramatically increased laminin E8 bead binding, and inhibited fertilin bead binding. Our results provide the first evidence that different states of an integrin (alpha6beta1) can interact with an extracellular matrix ligand (laminin) or a membrane-anchored cell surface ligand (ADAM 2).
Assuntos
Integrinas/metabolismo , Laminina/metabolismo , Glicoproteínas de Membrana/metabolismo , Metaloendopeptidases/metabolismo , Proteínas ADAM , Sequência de Aminoácidos , Animais , Sítios de Ligação , Desintegrinas/genética , Desintegrinas/metabolismo , Feminino , Fertilinas , Técnicas In Vitro , Integrina alfa6beta1 , Integrinas/química , Integrinas/genética , Ligantes , Masculino , Glicoproteínas de Membrana/genética , Metaloendopeptidases/genética , Camundongos , Camundongos Endogâmicos ICR , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/metabolismo , Transfecção , Zigoto/crescimento & desenvolvimentoRESUMO
Two Brazilian cases of Trypanosoma cruzi/HIV co-infection have recently been treated with azole derivatives. Benznidazole, the drug generally used for the treatment of Chagas disease, was initially used in one case but discontinued because of an adverse effect (retrobulbar neuritis) and replaced by itraconazole. The other case had oesophageal candidiasis, which was treated with ketoconazole, a drug that had already been shown to be effective in the treatment of Chagas disease. Since the medications were effective in reducing the T. cruzi parasitaemia in both patients, they probably helped prevent the severe morbidity sometimes associated with Chagas disease, although the HIV infections still proved fatal in both cases.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Doença de Chagas/tratamento farmacológico , Itraconazol/uso terapêutico , Cetoconazol/uso terapêutico , Tripanossomicidas/uso terapêutico , Adulto , Brasil , Quimioterapia Combinada , Evolução Fatal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parasitemia/tratamento farmacológico , Trypanosoma cruzi/efeitos dos fármacosRESUMO
Given the increasing use of carbon nanotubes (CNT) in several industries and technological applications, it is essential to perform in vivo toxicological studies with these nanomaterials to evaluate their potential ecotoxicity. Dopamine (DA) and serotonin (5HT) are key neurotransmitters for brain functions and behavioral responses. Determination of DA and 5HT were performed in brain samples from zebrafish Danio rerio exposed i.p. to single-walled CNT (SWCNT), besides analyzing acetylcholinesterase (AChE) and ectonucleotidases activity, lipid peroxidation and total antioxidant capacity. Results showed that treatment with SWCNT increased between 3 and 6-fold the concentration of DA and 5HT (pâ¯<â¯0.05). Similarly, a significant reduction (pâ¯<â¯0.05) in AChE activity was observed in the brains of SWCNT exposed zebrafish when compared to the control groups. Cholinergic, serotonergic, and dopaminergic systems, through AChE activity and serotonin and dopamine levels, respectively were affected by SWCNT in the zebrafish brain. Alterations in these neurotransmitters can potentially affect several physiological and behavioral that they control.
Assuntos
Antioxidantes/metabolismo , Nanotubos de Carbono/toxicidade , Síndromes Neurotóxicas , Neurotransmissores/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peixe-ZebraRESUMO
Mechanical unloading in microgravity during spaceflight is known to cause muscular atrophy, changes in muscle fiber composition, gene expression, and reduction in regenerative muscle growth. Although some limited data exists for long-term effects of microgravity in human muscle, these processes have mostly been studied in rodents for short periods of time. Here we report on how long-term (30-day long) mechanical unloading in microgravity affects murine muscles of the femoral Quadriceps group. To conduct these studies we used muscle tissue from 6 microgravity mice, in comparison to habitat (7), and vivarium (14) ground control mice from the NASA Biospecimen Sharing Program conducted in collaboration with the Institute for Biomedical Problems of the Russian Academy of Sciences, during the Russian Bion M1 biosatellite mission in 2013. Muscle histomorphology from microgravity specimens showed signs of extensive atrophy and regenerative hypoplasia relative to ground controls. Specifically, we observed a two-fold decrease in the number of myonuclei, compared to vivarium and ground controls, and central location of myonuclei, low density of myofibers in the tissue, and of myofibrils within a fiber, as well as fragmentation and swelling of myofibers. Despite obvious atrophy, muscle regeneration nevertheless appeared to have continued after 30 days in microgravity as evidenced by thin and short newly formed myofibers. Many of them, however, showed evidence of apoptotic cells and myofibril degradation, suggesting that long-term unloading in microgravity may affect late stages of myofiber differentiation. Ground asynchronous and vivarium control animals demonstrated normal, well-developed tissue structure with sufficient blood and nerve supply and evidence of regenerative formation of new myofibers free of apoptotic nuclei. Regenerative activity of satellite cells in muscles was observed both in microgravity and ground control groups, using Pax7 and Myogenin immunolocalization, as well as Myogenin expression analysis. In addition, we have detected positive nuclear immunolocalization of c-Jun and c-Myc proteins indicating their sensitivity to changes in gravitational loading in a given model. In summary, long-term spaceflight in microgravity caused significant atrophy and degeneration of the femoral Quadriceps muscle group, and it may interfere with muscle regenerative processes by inducing apoptosis in newly-formed myofibrils during their differentiation phase.
Assuntos
Fêmur/patologia , Atrofia Muscular/etiologia , Músculo Quadríceps/patologia , Voo Espacial , Ausência de Peso/efeitos adversos , Animais , Apoptose , Diferenciação Celular , Fêmur/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Miogenina/metabolismo , Músculo Quadríceps/metabolismo , RegeneraçãoRESUMO
Previously, we reported the effect of rearing conditions (plastic floors and air quality) on carcass injury development of broiler chickens at thermal comfort. In this study, the same rearing conditions were tested at thermal stress. The birds were reared in 2 climatic chambers, and the experiment followed a completely randomized design with one factor, flooring material: wood shaving or perforated plastic. The birds were divided into 16 experimental pens, being 8 females and 8 males. The studied parameters were the same as the previous study (ammonia concentration, carbon dioxide, performance, carcass yield, and variability, and scores of hygiene, gait and chest, and hocks and footpad lesions). Higher ammonia (15 ppm vs. 4 ppm) and carbon dioxide (1,000 ppm vs. 850 ppm) concentration was seen at d 42 for the wood shavings floor as compared to the perforated plastic floor, respectively. Regarding gender, males had better performance than females at 42 d of age on both floor types. Males reared on wood shavings showed a higher meat production (29.049 kg/m2) than females (24.700 kg/m2). There were observed breast lesion incidences of 10.4% (score 1) in males reared on the plastic floor, as well higher incidence of hock injury and footpad dermatitis. Chickens reared on plastic flooring showed better hygiene than chickens reared on wood shavings. Our findings revealed that the use of perforated plastic flooring in a heat stress situation can improve the air quality (less CO2 and NH3 concentration) and bird cleanliness. On the other hand, chickens are more susceptible to develop lesions in the breast, hock, and footpad. We conclude that the use of plastic flooring in heat stress conditions needs more attention, since chickens are more susceptible to develop lesions on the carcass, being a source of pain, impairing bird wellbeing and causing losses in meat production.
Assuntos
Poluição do Ar/análise , Criação de Animais Domésticos/métodos , Galinhas , Pisos e Cobertura de Pisos , Temperatura Alta/efeitos adversos , Abrigo para Animais , Amônia/análise , Animais , Dióxido de Carbono/análise , Galinhas/crescimento & desenvolvimento , Galinhas/lesões , Galinhas/fisiologia , Pisos e Cobertura de Pisos/classificação , Plásticos , Distribuição Aleatória , Estresse FisiológicoRESUMO
Hypertrophic terminally differentiated cardiac myocytes show increased sarcomeric organization and altered gene expression. Previously, we established a role for the nonreceptor tyrosine kinase Src in signaling cardiac myocyte hypertrophy. Here we report evidence that p130Cas (Cas) and focal adhesion kinase (FAK) regulate this process. In neonatal cardiac myocytes, tyrosine phosphorylation of Cas and FAK increased upon endothelin (ET) stimulation. FAK, Cas, and paxillin were localized in sarcomeric Z-lines, suggesting that the Z-line is an important signaling locus in these cells. Cas, alone or in cooperation with Src, modulated basal and ET-stimulated atrial natriuretic peptide (ANP) gene promoter activity, a marker of cardiac hypertrophy. Expression of the C-terminal focal adhesion-targeting domain of FAK interfered with localization of endogenous FAK to Z-lines. Expression of the Cas-binding proline-rich region 1 of FAK hindered association of Cas with FAK and impaired the structural stability of sarcomeres. Collectively, these results suggest that interaction of Cas with FAK, together with their localization to Z-lines, is critical to assembly of sarcomeric units in cardiac myocytes in culture. Moreover, expression of the focal adhesion-targeting and/or the Cas-binding proline-rich regions of FAK inhibited ANP promoter activity and suppressed ET-induced ANP and brain natriuretic peptide gene expression. In summary, assembly of signaling complexes that include the focal adhesion proteins Cas, FAK, and paxillin at Z-lines in the cardiac myocyte may regulate, either directly or indirectly, both cytoskeletal organization and gene expression associated with cardiac myocyte hypertrophy.
Assuntos
Cardiomegalia/metabolismo , Regulação da Expressão Gênica , Miocárdio/citologia , Fosfoproteínas/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas , Sarcômeros/fisiologia , Animais , Fator Natriurético Atrial/genética , Cardiomegalia/genética , Fracionamento Celular , Células Cultivadas , Proteína Substrato Associada a Crk , Meios de Cultura Livres de Soro , Proteínas do Citoesqueleto/metabolismo , Endotelinas/metabolismo , Endotelinas/farmacologia , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Genes Reporter , Immunoblotting , Imuno-Histoquímica , Proteínas dos Microfilamentos/metabolismo , Miocárdio/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Paxilina , Fosfoproteínas/genética , Fosforilação , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/genética , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Proteína p130 Retinoblastoma-Like , Sarcômeros/efeitos dos fármacos , Transdução de Sinais , Tensinas , Quinases da Família src/metabolismoRESUMO
Astronauts are exposed to radiation during space travel under conditions of dramatically reduced weightbearing activity. However, we know little about how gravity-dependent loading affects tissue sensitivity to radiation. We hypothesize gravity-dependent loading and irradiation share common molecular signaling pathways in bone cell progenitors that are sensitive to stress-induced reactive oxygen species (ROS), species capable of impacting skeletal health. To address this, progenitor cells with potential to differentiate into bone-forming osteoblasts were extracted from bone marrow, then cells were centrifuged (from 5-gravity (g) to 50-g for 5-180 min) on day 2 in culture, or were exposed to a single dose (1-5 Gy) of irradiation (137Cs 1 Gy/min) on day 3 or 4. Production of ROS was measured via fluorescence-activated cell sorting (FACS) using an oxidation-sensitive dye. Cell numbers were assessed by measurement of DNA content (CyQUANT). Osteoblastogenesis was estimated by measurement of alkaline phosphatase (ALP) activity and production of mineralized matrix (Alizarin Red staining). Transient centrifugation was a potent stimulus to bone marrow stromal cells, increasing production of ROS (1.2-fold), cell number (1.5-fold to 2.2-fold), and ALP activity (2.7-fold). Radiation also caused dose- and time-dependent increases in ROS production (1.1-fold to 1.4-fold) by bone marrow stromal cells, but inhibited subsequent osteoblast differentiation. In summary, gravity-dependent loading by centrifugation stimulated ROS production and increased numbers of osteoblasts. Although radiation increased production of ROS by bone marrow stromal cells, cell number and differentiation of osteoprogenitors appeared reduced. We conclude gravity-dependent loading and radiation both stimulate production of ROS and affect critical bone cell functions including growth and differentiation.
Assuntos
Células da Medula Óssea , Raios gama , Hipergravidade , Osteogênese/efeitos da radiação , Estresse Oxidativo , Células-Tronco , Fosfatase Alcalina/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/efeitos da radiação , Diferenciação Celular/fisiologia , Diferenciação Celular/efeitos da radiação , Células Cultivadas , DNA/metabolismo , Fêmur/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoblastos/efeitos da radiação , Osteogênese/fisiologia , Oxirredução , Estresse Oxidativo/fisiologia , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Células-Tronco/efeitos da radiação , Células Estromais/citologia , Células Estromais/metabolismo , Células Estromais/efeitos da radiação , Tíbia/citologiaRESUMO
The potential use of acetylcholinesterase (AChE) and metallothionein (MT) responses as biomarker of organophosphorous (OPs) and trace metal were assessed in fish Seriola dumerilli exposed to 0, 4, 6 mg/kg of malathion for 2, 7 and 13 days, and to 0, 50, 100, 250 mug/kg of Cd for 2 days. Brain AChE was significantly inhibited after 2 and 7 days of malathion exposure, in a dose-response manner, but no inhibition was observed after 13 days of exposure. When exposed to Cd for 2 days, S. dumerelli presented an increase in AChE activity at a concentration of 50 mug/kg, but a strong and dose-dependent AChE inhibition at 100 and 250 mug/kg. Cd treatment also caused a rapid increase in MTs concentration in liver, even at the lower concentration. Our experiments indicate that the measurement of hepatic MT concentration and brain AChE activity in S. dumerilli would be useful biomarkers of OP and Cd exposure and/or effects.
RESUMO
Glomerular filtration rates, as assessed by creatinine clearances were studied in 35 mild hypertensive, 104 moderate hypertensive and 167 severe hypertensive patients. The ages ranged from 16 to 65 years and the duration of hypertension varied between 0.5 and five years. The cause of hypertension was presumed idiopathic in all but 13 severe hypertensives in whom renal biopsies were performed. The mean creatinine clearances in mild, moderate and severe hypertensives were 154.5 +/- 15.0, 83.0 +/- 26.0, 15.0 +/- 14.0 (male) and 147.0 +/- 20.0, 78.0 +/- 15.0 and 14.3 +/- 13.0 (female) respectively. A creatinine clearance of greater than 125 ml per minute was recorded in all patients with mild hypertension. This finding might be a feature of early structural and functional renal damage in mild hypertension.
Assuntos
Creatinina/metabolismo , Hipertensão/metabolismo , Adolescente , Adulto , Idoso , Creatinina/análise , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The effects of contaminants on the biochemical parameters of the intensively farmed mussel Perna perna, are unknown. The aim of this study was to compare biochemical responses in mussels held in clean and contaminated sites in Santa Catarina Island, Brazil. Mussels were transplanted from a farming area, Ratones Grande Island (RGI), to two contaminated sites, Itacorubi (ITAC) and Hercílio Luz Bridge (HLB). A reference group was kept at RGI. After 150 and 180 days of exposure, the digestive glands of the mussels were analyzed for catalase, glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferase (GST) activities. No changes were observed in the catalase activity, in both periods. Low G6PDH activity was observed in mussels transplanted for 150 days at the ITAC site. Increased GST activity was observed in mussels from ITAC and HLG sites after 180 days. These responses are probably related to the augmented discharges of domestic effluents associated with elevated rainfall index.
Assuntos
Bivalves/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Bivalves/metabolismo , Brasil , Catalase/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Glutationa Transferase/metabolismo , NADP/metabolismoRESUMO
Reports on children presenting symptoms compatible with the chronic phase of Chagas disease are sporadic. We report a case of a 7-year-old boy who had megaesophagus and megacolon, both of them a consequence of the trypanosomiasis. The etiology was established by means of laboratory and histological features. Based on epidemiological data, the authors concluded that vertical transmission was the most probable route of acquisition. This diagnosis should be considered in children presenting similar complaints, even those living away from endemic areas.
Assuntos
Doença de Chagas/diagnóstico , Acalasia Esofágica/diagnóstico , Megacolo/diagnóstico , Doença de Chagas/complicações , Doença de Chagas/transmissão , Criança , Acalasia Esofágica/etiologia , Humanos , Transmissão Vertical de Doenças Infecciosas , Masculino , Megacolo/etiologiaRESUMO
The first two Uruguayan cases of botryomycosis were diagnosed in white adult male patients with cutaneous lesions. Staphylococcus aureus was the etiologic agent in both cases. In one of them, however, Pseudomonas aeruginosa was also identified during relapse. General comments on diagnosis and pathogenesis of the disease are made.
Assuntos
Infecções Cutâneas Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Cutâneas Estafilocócicas/microbiologia , UruguaiRESUMO
Thirty-two monkeys were captured and adapted to laboratory conditions captives isolated. They were submitted to multiple xenodiagnosis which were negative. Twelve were infected intraperitoneally with different strains of T. cruzi (1.10(5) to 5.10(6)). Twenty were the control group. Between on to six years both the control group and the infected monkeys, were submitted to xenodiagnosis, serological testing clinical examination and electrocardiography. The clinical examination and the electrocardiogram were always normal. The monkey were autopsied and histological examination detected in the infected group four monkeys with evidence of disease: one with parasites in the tissue and three with chronic myocarditis. Parasitaemia was in 66.66% of the monkeys in the acute phase and the serology was positive in 91.66% in the chronic phase. The authors concluded that Cebus monkeys were not susceptible to the development of the disease but they could be utilized to maintain of such strains and studies of serological research in long-terms infections.