RESUMO
Polyglucosan bodies are accumulations of insoluble glucose polymers and proteins that form intracytoplasmic inclusions in the brain, large numbers of which can be indicative of neurodegenerative diseases such as Lafora disease. Montserrat orioles (Icterus oberi) are an icterid passerine endemic to Montserrat with conservation populations maintained in captivity abroad. We demonstrate that polyglucosan bodies are unusually abundant in the cerebellar molecular and Purkinje cell layers and cerebellar peduncles of captive-bred and wild-caught Montserrat orioles. The bodies are periodic acid-Schiff positive and diastase resistant and label with concanavalin A and for ubiquitin, consistent with those seen in humans. We found no association of the polyglucosan bodies with concurrent neurological lesions or clinical signs, nor with EPM2A and EPM2B gene mutations associated with Lafora disease. We conclude that an abundance of cerebellar polyglucosan bodies may be a normal finding in aged Montserrat orioles and not a threat to the captive breeding population.
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Ivermectin is one of the most widely used drugs for parasite control. Previous studies have shown a reduction in the abundance and diversity of "non-target" coprophilous organisms due to the presence of ivermectin (IVM) in bovine faecal matter (FM). Due to its breadth of behavioural habits, Calliphora vicina is a suitable dipteran species to evaluate the effects of IVM in FM. The aim of this work was to evaluate the effect of five concentrations of IVM in FM (3000, 300, 100, 30, and 3 ng/g) on the development of C. vicina. The following endpoints were evaluated: survival (between the first larval stage and emergence of new adults), larval development times to pupation and pupation times to adult, and adult emergence (% sex) and LC50. Sampling was performed from larval hatching at 60 and 120 min and at 3, 4, 5, and 12 h, and every 24 h specimens were weighed until pupae were observed. Data were analysed by ANOVA using a non-parametric Kruskal-Wallis test and as a function of elapsed development time and accumulated degree hours (ADH). Mortality at 3000 and 300 ng/g was 100% and 97%, respectively. There were statistically significant delays in adult emergence time (p = 0.0216) and in the ADH (p = 0.0431) between the control group (C) and 100 ng/g. The LC50 was determined at 5.6 ng/g. These results demonstrate the lethal and sub-lethal effects of IVM on C. vicina, while highlighting the usefulness of this species as a bioindicator for ecotoxicological studies.
Assuntos
Calliphoridae , Fezes , Ivermectina , Larva , Animais , Ivermectina/farmacologia , Calliphoridae/efeitos dos fármacos , Calliphoridae/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Fezes/parasitologia , Bovinos , Análise de Sobrevida , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Feminino , Antiparasitários/farmacologia , Masculino , Dose Letal Mediana , Dípteros/efeitos dos fármacos , Dípteros/crescimento & desenvolvimentoRESUMO
Phosphorus (P) is a vital nutrient for plant growth. P availability is generally low in soils, and plant responses to low P availability need to be better understood. In a previous study, we studied the growth and physiological responses of 24 species to low P availability in the soil and verified of eucalypts, five (Eucalyptus acmenoides, E. grandis, E. globulus, E. tereticornis, and Corymbia maculata) contrasted regarding their efficiency and responsiveness to soil P availability. Here, we obtained the metabolomic and lipidomic profile of leaves, stems, and roots from these species growing under low (4.5 mg dm-3) and sufficient (10.8 mg dm-3) P in the soil. Disregarding the level of P in the soils, P allocation was always higher in the stems. However, when grown in the P-sufficient soil, the stems steadily were the largest compartment of the total plant P. Under low P, the relative contents of primary metabolites, such as amino acids, TCA cycle intermediates, organic acids and carbohydrates, changed differently depending on the species. Additionally, phosphorylated metabolites showed enhanced turnover or reductions. While photosynthetic efficiencies were not related to higher biomass production, A/Ci curves showed that reduced P availability increased the eucalypt species' Vcmax, Jmax and photosynthetic P-use efficiency. Plants of E. acmenoides increased galactolipids and sulfolipids in leaves more than other eucalypt species, suggesting that lipid remodelling can be a strategy to cope with the P shortage in this species. Our findings offer insights to understand genotypic efficiency among eucalypt species to accommodate primary metabolism under low soil P availability and eventually be used as biochemical markers for breeding programs.
RESUMO
The ethanol surface reaction over CeO2 nanooctahedra (NO) and nanocubes (NC), which mainly expose (111) and (100) surfaces, respectively, was studied by means of infrared spectroscopy (TPSR-IR), mass spectrometry (TPSR-MS), and density functional theory (DFT) calculations. TPSR-MS results show that the production of H2 is 2.4 times higher on CeO2-NC than on CeO2-NO, which is rationalized starting from the different types of adsorbed ethoxy species controlled by the shape of the ceria particles. Over the CeO2(111) surface, monodentate type I and II ethoxy species with the alkyl chain perpendicular or parallel to the surface, respectively, were identified. Meanwhile, on the CeO2(100) surface, bidentate and monodentate type III ethoxy species on the checkerboard O-terminated surface and on a pyramid of the reconstructed (100) surface, respectively, are found. The more labile surface ethoxy species on each ceria nanoshape, which are the monodentate type I or III ethoxy on CeO2-NO and CeO2-NC, respectively, react on the surface to give acetate species that decompose to CO2 and CH4, while H2 is formed via the recombination of hydroxyl species. In addition, the more stable monodentate type II and bidentate ethoxy species on CeO2-NO and CeO2-NC, respectively, give an ethylenedioxy intermediate, the binding of which is facet-dependent. On the (111) facet, the less strongly bound ethylenedioxy desorbs as ethylene, whereas on the (100) facet, the more strongly bound intermediate also produces CO2 and H2 via formate species. Thus, on the (100) facet, an additional pathway toward H2 formation is found. ESR activity measurements show an enhanced H2 production on the nanocubes.
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Establishing quality reference values (QRVs) for rare earth elements (REEs) in soils is essential for the screening of these emergent contaminants. Currently, Brazil has the second-largest reserve of REEs, but data regarding background concentrations and distributions in soils remain scarce. The aim of this study was to establish the QRVs and assess the spatial distribution of REEs in soils, including REE fractionations and anomalies in (Piauí) state (251,529.186 km2), northeastern Brazil. This study reports the most detailed data on REE geochemistry in Brazilian soils. A total of 243 composite soil samples was collected at 0-20 cm depth. The mean background concentrations in soils followed the abundance of the earth's upper crust: Ce > La > Nd > Pr > Sm > Dy > Gd > Er > Yb > Eu > Tb > Lu. The ∑REEs (mg kg-1) showed the following order based on the individual mesoregions of Piauí state: Southeast (262.75) > North and Central-North (89.68) > Southwest (40.33). The highest QRVs were observed in the Southeast mesoregion. The establishment of QRVs based on the mesoregion scale improves data representativeness and the monitoring of natural REE values by identifying hot spots. Geostatistical modeling indicated significant local variability, especially in the Southeast mesoregion. The levels of these elements in this spatial zone are naturally higher than the other values across Piauí state and the mesoregion itself and indicate a high potential to exceed the QRVs. Our approach provides much needed data to help strengthen policies for both human health and environmental protection.
Assuntos
Metais Terras Raras , Poluentes do Solo , Monitoramento Ambiental , Política Ambiental , Geologia , Humanos , Metais Terras Raras/análise , Solo , Poluentes do Solo/análiseRESUMO
A series of benzo [d] [1,3] azoles 2-substituted with benzyl- and allyl-sulfanyl groups were synthesized, and their cytotoxic activities were in vitro evaluated against a panel of six human cancer cell lines. The results showed that compounds BTA-1 and BMZ-2 have the best inhibitory effects, compound BMZ-2 being comparable in some cases with the reference drug tamoxifen and exhibiting a low cytotoxic effect against healthy cells. In silico molecular coupling studies at the tamoxifen binding site of ERα and GPER receptors revealed affinity and the possible mode of interaction of both compounds BTA-1 and BMZ-2.
Assuntos
Antineoplásicos/química , Antineoplásicos/metabolismo , Azóis/química , Azóis/metabolismo , Citotoxinas/química , Citotoxinas/metabolismo , Simulação de Acoplamento Molecular/métodos , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Azóis/síntese química , Azóis/farmacologia , Sítios de Ligação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/síntese química , Citotoxinas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Receptor alfa de Estrogênio/metabolismo , Humanos , Células MCF-7 , Estrutura Molecular , Células PC-3 , Relação Estrutura-Atividade , Tamoxifeno/metabolismo , Tamoxifeno/farmacologiaRESUMO
The resistance of Haemonchus contortus to synthetic anthelmintics is of increasing concern; and different strategies are being evaluated to improve parasite control. The present study investigated the in vitro effects of combinations of synthetic compounds and monoterpenes. Additionally, the chemical association of the best combinations and their impact on the ultrastructural and biophysical properties of H. contortus eggs was evaluated. We assessed the efficacy of the monoterpenes, carvacrol, thymol, r-carvone, s-carvone, citral, and p-cymene and the anthelmintics, albendazole and levamisole using the egg hatch test (EHT) and the larval migration inhibition test (LMIT), respectively. The minimum effective concentrations of the monoterpenes, according to the EHT (efficacy ranging from 4.4%-11.8%) and LMIT (efficacy ranging from 5.6%-7.4%), were used in combination with different concentrations of synthetic compounds, and the IC50 and synergism rate (SR) were calculated. Fourier-transform infrared spectroscopy (FTIR) was used to analyze the chemical association between the best combinations as revealed by the in vitro tests (albendazole and levamisole with r-carvone or s-carvone). Atomic force microscopy (AFM) was used to assess the ultrastructural and biophysical properties of H. contortus eggs treated with the albendazole and r-carvone combination. Among the monoterpenes, the highest efficacies were exhibited by carvacrol (IC50 = 185.9 µg/mL) and thymol (IC50 = 187.0 µg/mL), according to the EHT, and s-carvone and carvacrol (IC50 = 1526.0 and 1785.3 µg/mL, respectively), according to the LMIT. According to the EHT, albendazole showed a slight statistically significant synergism in combination with r-carvone (SR = 3.8) and s-carvone (SR = 3.0). According to the LMIT, among the monoterpenes, r-carvone (SR = 1.7) and s-carvone (SR = 1.7) showed an increase in efficacy with levamisole; however, this was not statistically significant. The FTIR spectra of albendazole and levamisole, in association with r-carvone and s-carvone, indicated the presence of chemical interactions between the synthetic and natural molecules, contributing to the possible synergistic effects of these associations. Eggs treated with albendazole and r-carvone showed an increase in roughness and a decrease in height, suggesting that the treatment induced damage to the egg surface and an overflow of its internal contents. Overall, the combination of albendazole with r-carvone and s-carvone was efficacious against H. contortus, demonstrating a chemical association between the compounds; the significant changes in the egg ultrastructure justify this efficacy.
Assuntos
Anti-Helmínticos/síntese química , Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos , Monoterpenos/química , Monoterpenos/farmacologia , Animais , Haemonchus/ultraestrutura , Larva/efeitos dos fármacos , Larva/fisiologia , Microscopia de Força Atômica , Estrutura Molecular , Atividade Motora/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-AtividadeRESUMO
A series of Pt(II) complexes of the type [Pt(1,10-phenanthroline)(SArFn)2] (SArFn = SC6H3-3,4-F2(1); SC6F4-4-H (2); SC6F5(3)) were synthesized from [Pt(1,10-phenanthroline)(Cl)2] and [Pb(SArFn)2] via metathesis reactions. The complexes were fully characterized including the unambiguous determination of their molecular structures by single-crystal X-ray diffraction techniques, showing the metal centers to be into a slightly distorted square-planar environments. The in vitro cytotoxic activity of the complexes was evaluated on six cancerous cell lines, i.e: glial cells of nervous central system (U-251), prostate (PC-3), leukemia (K-562), colon (HCT-15), breast (MCF-7) and lung (SKLU-1); we also included a healthy cell line of COS-7 (African green monkey kidney) for comparative purposes. We found that complex 2 was selective for PC-3. In addition, the IC50 values for the series of complexes were determined using the U-251, HCT-15 and SKLU-1 cancerous cell lines, as well as in the healthy cell line (COS-7), where complex 1 exhibited the best activity, with IC50 values going from 4.56 to 4.78 µM. These studies where further complemented with DNA docking theoretical calculations and DNA affinity experiments.
Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/farmacologia , Fenantrolinas/química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X/métodos , Humanos , Técnicas In Vitro , Estrutura Molecular , Neoplasias/patologia , Compostos Organoplatínicos/química , Relação Estrutura-AtividadeRESUMO
The combination of synthetic anthelmintics and bioactive phytochemicals may be a pharmacological tool for improving nematode control in livestock. Carvone (R-CNE) has shown in vitro activity against gastrointestinal nematodes; however, the anthelmintic effect of bioactive phytochemicals either alone or combined with synthetic drugs has been little explored in vivo. Here, the pharmacological interaction of abamectin (ABM) and R-CNE was assessed in vitro and in vivo. The efficacy of this combination was evaluated in lambs naturally infected with resistant gastrointestinal nematodes. Additionally, the ligand and molecular docking of both molecules to P-glycoprotein (P-gp) was studied in silico. The presence of R-CNE produced a significant (p < 0.05) increase of Rho123 and ABM accumulation in the intestinal explants. After 60 min of incubation, Rho123 incubated with R-CNE had a 67 ± 21% higher concentration (p < 0.01) than when it was incubated alone. In the case of ABM, a significant increase in the intestinal concentrations was observed at 15 and 30 min after incubation with R-CNE. In the in vivo assay, no undesirable effects were observed after the oral administration of R-CNE. The coadministration of the natural compound prolonged ABM absorption in lambs. ABM T ½ absorption was 1.57-fold longer (p < 0.05) in the coadministered group. Concentrations of R-CNE between 420 and 2,593 ng/mL were detected in the bloodstream between 1 and 48 h posttreatment. The in vivo efficacy of ABM against gastrointestinal nematodes increased from 94.9 to 99.8% in the presence of R-CNE, with the lower confidence interval limit being >90%. In vitro/in vivo pharmacoparasitological studies are relevant for the knowledge of the interactions and the efficacy of bioactive natural products combined with synthetic anthelmintics. While ADMET (absorption, distribution, metabolism, excretion, and toxicity) predictions and the molecular docking study showed a good interaction between ABM and P-gp, R-CNE does not appear to modulate this efflux protein. Therefore, the pharmacokinetic-pharmacodynamic effect of R-CNE on ABM should be attributed to its effect on membrane permeability. The development of pharmacology-based information is critical for the design of successful strategies for the parasite control.
RESUMO
Thorium (Th) is one of the main sources of natural radiation to ecosystems. However, data regarding Th concentrations in rocks, soil, water and sediments are currently scarce. Accordingly, this study aimed to establish background concentrations and quality reference values (QRVs) for Th in the environmentally impacted Ipojuca River catchment in Brazil, where the weathering of granites releases Th into the environment. Additionally, the study aimed to calculate Th fluxes in water, and both bed and suspended sediment. The mean Th concentration in the study catchment soils was 28.6 mg kg-1. The QRV for Th was estimated to be 21 mg kg-1 and 86.3 Bq kg-1. Bed and suspended sediment-associated concentrations ranged from 2.8 to 32.9 mg kg-1. Suspended sediment-associated discharge (3.42 t year-1) accounted for more than 99% of the total Th flux, while the dissolved phase transport was negligible in comparison. At the downstream cross section in the study catchment, suspended sediment samples exhibited Th concentrations similar to those observed in rivers impacted by mining activities. The discharge of sediment to the ocean from the study area is mainly triggered by soil erosion processes in the hotspot region (middle-inferior course). It is essential to identify Th hotspots before establishing environmental policies regarding human health and environmental protection.
Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Tório/análise , Brasil , Ecossistema , Sedimentos Geológicos/química , Rios , Solo/química , ÁguaRESUMO
The combination of the organophosphate (OP) chlorpyrifos (CPF) and the pyrethroid cypermethrin (CPM) is commonly marketed as pour-on formulations for the control of sheep lice, ked, and blowflies. CPF irreversibly inhibits acetylcholinesterases (AChE), while pyrethroids are not AChE inhibitors. However, combinations of pyrethroids with OPs showed a highly synergistic effect on AChE inhibition. Thus, the aim of the current work was to evaluate in vitro and in vivo the inhibitory potency of both pesticides, alone and in combination with AChE and butyrylcholinesterase (BChE) activities in sheep blood. In vitro, IC50 values were similar after CPF or CPF plus CPM incubations. The pour-on coadministration of recommended doses of CPF and CPM did not cause a significant inhibition of AChE and BChE in sheep blood. Only slight percentages of inhibition of their catalytic activities were observed when both drugs were given at 4-fold higher dose rates. The lower systemic availability of topical administration of OPs in sheep may help to explain the lower degree of inhibition of blood AChE and BChE in vivo. The results emerged from this research are a further contribution to the knowledge of the risks of implementing higher dosage regimens of OPs-containing antiparasitic formulations.
Assuntos
Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Clorpirifos/efeitos adversos , Inibidores da Colinesterase/efeitos adversos , Piretrinas/efeitos adversos , Ovinos/sangue , Administração Tópica , Animais , Clorpirifos/administração & dosagem , Clorpirifos/uso terapêutico , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/uso terapêutico , Combinação de Medicamentos , Inseticidas/administração & dosagem , Inseticidas/efeitos adversos , Inseticidas/uso terapêutico , Masculino , Piretrinas/administração & dosagem , Piretrinas/uso terapêuticoRESUMO
OBJECTIVES/HYPOTHESIS: To investigate the cochleovestibular apparatus bilaterally in children with isolated unilateral bony cochlear nerve canal (bCNC) stenosis. STUDY DESIGN: Retrospective review. METHODS: Imaging studies of children with unilateral bCNC stenosis (<1.0 mm) on computed tomography imaging (N = 36) were compared with controls imaged due to trauma without temporal bone injury (N = 32). Twenty-six measurements were obtained in each ear, assessing the bony internal auditory canal (IAC), cochlea, and vestibular end-organs, and were analyzed using one-way analysis of variance for intersubject comparisons and paired t tests for intrasubject comparisons with a Bonferroni adjustment for multiple comparisons (P = .0006). RESULTS: Patients with bCNC stenosis had a smaller IAC (P < .000) and cochlea (P < .000) on the stenotic side as compared with controls. Although the vestibular end-organ was also smaller in bCNC ears, this difference was not significant. The contralateral ear also had a smaller bCNC (P < .000) and cochlea (P < .000) as compared with controls, although to a lesser degree than the stenotic side. CONCLUSIONS: Children with unilateral bCNC stenosis have abnormal biometry of both the cochlea and the vestibular end-organ in the affected and the normal contralateral ear as compared with controls. LEVEL OF EVIDENCE: 3b Laryngoscope, 129:2403-2408, 2019.
Assuntos
Cóclea/anormalidades , Nervo Coclear/patologia , Tomografia Computadorizada por Raios X , Vestíbulo do Labirinto/anormalidades , Doenças do Nervo Vestibulococlear/patologia , Criança , Pré-Escolar , Cóclea/diagnóstico por imagem , Nervo Coclear/diagnóstico por imagem , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/etiologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Vestíbulo do Labirinto/diagnóstico por imagem , Doenças do Nervo Vestibulococlear/congênito , Doenças do Nervo Vestibulococlear/diagnóstico por imagemRESUMO
Rare earth elements (REEs) have been recently recognized as emergent pollutants in rivers. However, data regarding REE fluxes in association with either bed or suspended are scarce. To address this knowledge gap, we determined the concentrations and fluxes of La, Ce, Pr, Nd, Sm, Eu, Gd, Yb, Lu, Dy, Er, Ho, Tb, and Tm in bed and suspended sediment samples of a representative polluted Brazilian River. Sediment-associated data on REEs were placed in the context of corresponding background concentrations in soils under natural conditions along the Ipojuca watershed. Light rare earth elements (LREEs) comprised more than 94% of the total REEs associated with bed and suspended sediments. Suspended sediments accounted for more than 95% of the total REE flux. The Ce and Nd fluxes of about 7 t year-1 underscore the importance of including REEs in future estimations of global suspended sediment-associated element fluxes. In contrast, bedload often transported less than 0.0007 t year-1 of each REE. The main sources of pollution in the Ipojuca River are anthropogenic, likely due to domestic effluent and waste water from industrial and agricultural operations-major causes of sediment-associated Gd transport in polluted streams.
Assuntos
Sedimentos Geológicos/análise , Metais Terras Raras/análise , Poluentes Químicos da Água/análise , Agricultura , Brasil , Monitoramento Ambiental/métodos , Rios/química , Solo/química , Poluentes do Solo/análiseRESUMO
O método conhecido como análise fenomenal, ou a análise do que uma dada situação significa à uma pessoa, tem influenciando, em anos recentes, as áreas de psicoterapia, aconselhamento e teoria da personalidade. A questão é saber o que esse método tem a oferecer ao estudo de fenômenos psicológicos gerais. Vários psicólogos sabem ou especulam sobre a possível contribuição da análise fenomenal para a psicologia geral. Esse fato foi enfaticamente reconhecido por Koehler: "Nunca, eu acredito, seremos capazes de resolver quaisquer problemas relativos a princípios últimos enquanto não retornarmos à fonte dos nossos conceitos - em outras palavras, enquanto não utilizarmos o método fenomenológico, a análise qualitativa da experiência" (Koehler, 1938, p. vii). MacLeod (1951, p. 215) tentou transmitir o valor da análise fenomenal ao declarar: "Ser científico é ser curioso de uma maneira disciplinada, isto é, tentar compreender (não meramente prever ou controlar) com a ajuda dos melhores métodos de observação, dedução e verificação". Em referência à psicologia social, Asch (1953, p. X) disse: "Eu entendo como necessário manter em primeiro plano os modos humanos de experienciar o mundo da natureza e do homem, visto que as ações sociais de que falamos são aquelas de seres conscientes que atuam, em grande parte, em termos daquilo que compreendem e sentem". Quando o humano começa a pensar ou falar sobre suas experiências, ele está tentando expressar suaconsciência. É através desta formulação que a consciência se torna conhecimento conceitual e uma condição necessária para qualquer comunicação relativa a fenômenos subjetivos. A consciência implícita e vaga de um fenômeno subjetivo complexo é capaz de mudar graças ao processo de expressão e de formulação em conhecimento explícito de seus componentes. Esse processo é conhecido como explicação. É o que temos de essencial no processo de psicoterapia, no qual o paciente gradualmente aprende a expressar sua experiência implícita, vaga e dolorosa em uma descrição explicitamente reconhecida do que está ocorrendo em sua vida subjetiva.
Assuntos
Emoções , Teoria GestálticaRESUMO
Angiogenesis is a coordinated process tightly regulated by the balance between Delta-like-4 (DLL4) and Jagged-1 (JAG1) in endothelial cells. Here we show that galectin-3 (gal-3), a glycan-binding protein secreted by cancer cells under hypoxic conditions, triggers sprouting angiogenesis, assisted by hypoxic changes in the glycosylation status of endothelial cells that enhance binding to gal-3. Galectin-3's proangiogenic functions were found to be predominantly dependent on the Notch ligand JAG1. Differential direct binding to JAG1 was shown by surface plasmon resonance assay. Upon binding to Notch ligands, gal-3 preferentially increased JAG1 protein half-life over DLL4 and preferentially activated JAG1/Notch-1 signaling in endothelial cells. JAG1 overexpression in Lewis lung carcinoma cells accelerated tumor growth in vivo, but this effect was prevented in Lgals3-/- mice. Our findings establish gal-3 as a molecular regulator of the JAG1/Notch-1 signaling pathway and have direct implications for the development of strategies aimed at controlling tumor angiogenesis.
Assuntos
Galectina 3/metabolismo , Proteína Jagged-1/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica/metabolismo , Receptores Notch/metabolismo , Animais , Proteínas Sanguíneas , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Galectina 3/genética , Galectinas , Humanos , Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ligantes , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Modelos Biológicos , Neoplasias/genética , Neovascularização Patológica/genética , Ligação Proteica , Transdução de SinaisRESUMO
At risk of committing entomological heresy, we question the identity of a dung-burying beetle species that originates from Africa and has been introduced first into Hawaii and subsequently to Australasia, North America, and South America (Fincher 1986; Edwards 2007; Noriega et al. 2010) for pasture improvement and biological control of dung-breeding flies (Waterhouse 1974; Bornemissza 1979). Under the name Onthophagus gazella (Fabricius 1787), it was the first species selected for introduction into Australia by the CSIRO Dung Beetle Project (Bornemissza 1976; Edwards 2007). Firstly, in 1968, a "tropical strain" was introduced from Hawaii where it had become established after introduction from Zimbabwe in 1957 (Markin & Yoshioka 1998). Later, after establishment of the CSIRO Dung Beetle Research Unit in Pretoria in 1970, a "cold" or "even rainfall strain" was introduced into Australia directly from South Africa (Bornemissza 1976) (even rainfall region = south coast of Eastern Cape). The species was subsequently introduced into the southern continental United States of America (Victoria County, Texas) from Hawaii (Montes de Oca & Halffter 1998) then elsewhere into southeastern and southwestern states from Hawaii and breeding colonies from Australia (Anderson & Loomis 1978). It has since expanded its range through Mexico, Central America, and the Caribbean to coastal Colombia (Kohlmann 1994; Noriega 2002; Noriega et al. 2006, 2011). Expansion of its range within central southern South America (Noriega et al. 2010) has been assisted by introductions into Brazil from the United States of America since the 1980s (Bianchin et al. 1998), and others into Venezuela and Chile (Vidaurre et al. 2008). More recently, it has been introduced into quarantine and field trials in New Zealand (Forgie et al. 2013) using individuals originating from the south coast of the Eastern Cape and Northwest Province of South Africa (S. Forgie, personal communication).
Assuntos
Besouros , África , Animais , Região do Caribe , América do Norte , América do SulRESUMO
1. Precision-cut liver slices (PCLS) from food-producing animals have not been extensively used to study xenobiotic metabolism, and thus information on this field of research is sparse. 2. The aims of the present work were to further validate the technique of production and culture of bovine PCLS and to characterize the metabolic interaction between the anthelmintic albendazole (ABZ) and the flavin-monooxygenase (FMO) inhibitor methimazole (MTZ). 3. Nine steers were used as donors. PCLS were produced and incubated under two methods: a dynamic organ culture (DOC) incubator and a well-plate (WP) system. 4. Tissue viability, assessed through both structural and functional markers, was preserved throughout 12 h of incubation. ABZ was metabolized to its (+) and (-) albendazole sulfoxide stereoisomers (ABZSO) in bovine PCLS. The interaction between ABZ and MTZ resulted in a reduction (p < 0.001) in the rates of appearance of (+) ABZSO. Conversely, in presence of MTZ, the rates of appearance of (-) ABZSO increased under both systems (p < 0.05). 5. Both culture systems were suitable for assessing the interaction between ABZ and MTZ. 6. Overall, the results presented herein show that PCLS are a useful and reliable tool for short-term studies on metabolic drug-drug interactions in the bovine species.
Assuntos
Interações Medicamentosas , Fígado/metabolismo , Administração Oral , Albendazol/análogos & derivados , Albendazol/metabolismo , Animais , Anti-Helmínticos/metabolismo , Bovinos , Metimazol/metabolismo , Microssomos Hepáticos/metabolismo , EstereoisomerismoRESUMO
ST6GalNAc-I, the sialyltransferase responsible for sialyl-Tn (sTn) synthesis, has been previously reported to be positively associated with cancer aggressiveness. Here we describe a novel sTn-dependent mechanism for chemotherapeutic resistance. We show that sTn protects cancer cells against chemotherapeutic-induced cell death by decreasing the interaction of cell surface glycan receptors with galectin-3 and increasing its intracellular accumulation. Moreover, exogenously added galectin-3 potentiated the chemotherapeutics-induced cytotoxicity in sTn non-expressing cells, while sTn overexpressing cells were protected. We also found that the expression of sTn was associated with a reduction in galectin-3-binding sites in human gastric samples tumors. ST6GalNAc-I knockdown restored galectin-3-binding sites on the cell surface and chemotherapeutics sensibility. Our results clearly demonstrate that an interruption of O-glycans extension caused by ST6GalNAc-I enzymatic activity leads to tumor cells resistance to chemotherapeutic drugs, highlighting the need for the development of novel strategies to target galectin-3 and/or ST6GalNAc-I.
Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Galectina 3/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Animais , Antígenos Glicosídicos Associados a Tumores/genética , Antígenos Glicosídicos Associados a Tumores/metabolismo , Proteínas Sanguíneas , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Galectinas , Glicosilação , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Processamento de Proteína Pós-Traducional , Transporte Proteico , Interferência de RNA , Sialiltransferases/genética , Sialiltransferases/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Fatores de Tempo , Transfecção , Carga TumoralRESUMO
The current work evaluated the inhibitory potency of the herbicide glyphosate (GLP) on acetylcholinesterase (AChE) activity in male and female rat tissues. The AChE activity in brain was higher (p<0.05) than those observed in kidney (females: 2.2-fold; males: 1.9-fold), liver (females: 6-fold; males: 6.9-fold) and plasma (females: 14.7-fold; males: 25.3-fold). Enzyme activities were higher in presence of 10mM GLP compared to those measured at an equimolar concentration of the potent AChE inhibitor dichlorvos (DDVP). Moreover, IC50s for GLP resulted between 6×10(4)- and 6.8×10(5)-fold higher than those observed for DDVP. In conclusion, GLP is a weak inhibitor of AChE in rats.
Assuntos
Inibidores da Colinesterase/toxicidade , Glicina/análogos & derivados , Herbicidas/toxicidade , Acetilcolinesterase/sangue , Acetilcolinesterase/metabolismo , Animais , Encéfalo/enzimologia , Feminino , Glicina/toxicidade , Rim/enzimologia , Fígado/enzimologia , Masculino , Ratos Wistar , GlifosatoRESUMO
One of the ways to develop health simulations is through the use of computers. This paper presents the use of Intelligent Computer-aided Instruction (ICAI) for the development of an interactive simulator for learning Cardio Pulmonary Resucitation (CPR) which incorporates online tutorials, training and evaluation.