RESUMEN
OBJECTIVE: To assess the effects of arginine, with or without sodium fluoride (NaF; 1,450 ppm), on saliva-derived microcosm biofilms and enamel demineralization. METHODS: Saliva-derived biofilms were grown on bovine enamel blocks in 0.2 % sucrose-containing modified McBain medium, according to six experimental groups: control (McBain 0.2 %); 2.5 % arginine; 8 % arginine; NaF; 2.5 % arginine with NaF; and 8 % arginine with NaF. After 5 days of growth, biofilm viability was assessed by colony-forming units counting, laser scanning confocal microscopy was used to determine biofilm vitality and extracellular polysaccharide (EPS) production, while biofilm metabolism was evaluated using the resazurin assay and lactic acid quantification. Demineralization was evaluated by measuring pH in the culture medium and calcium release. Data were analyzed by Kruskal-Wallis' and Dunn's tests (p < 0.05). RESULTS: 8 % arginine with NaF showed the strongest reduction in total streptococci and total microorganism counts, with no significant difference compared to arginine without NaF. Neither 2.5 % arginine alone nor NaF alone significantly reduced microbial counts compared to the control, although in combination, a reduction in all microbial groups was observed. Similar trends were found for biofilm vitality and EPS, and calcium released to the growth medium. CONCLUSIONS: 8 % Arginine, with or without NaF, exhibited the strongest antimicrobial activity and reduced enamel calcium loss. Also, NaF enhanced the effects of 2.5 % arginine, yielding similar results to 8 % arginine for most parameters analyzed. CLINICAL SIGNIFICANCE: The results provided further evidence on how arginine, with or without NaF, affects oral microcosm biofilms and enamel mineral loss.
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Arginina , Biopelículas , Cariostáticos , Esmalte Dental , Microscopía Confocal , Saliva , Fluoruro de Sodio , Desmineralización Dental , Biopelículas/efectos de los fármacos , Arginina/farmacología , Fluoruro de Sodio/farmacología , Esmalte Dental/efectos de los fármacos , Esmalte Dental/microbiología , Bovinos , Animales , Desmineralización Dental/prevención & control , Desmineralización Dental/microbiología , Cariostáticos/farmacología , Saliva/microbiología , Saliva/metabolismo , Saliva/efectos de los fármacos , Concentración de Iones de Hidrógeno , Viabilidad Microbiana/efectos de los fármacos , Calcio/análisis , Calcio/metabolismo , Streptococcus/efectos de los fármacos , Xantenos/farmacología , Recuento de Colonia Microbiana , Oxazinas/farmacologíaRESUMEN
The influence of the method of evaluating developmentally competent oocytes on their viability after cryopreservation still needs to be better understood. The objective of this study was to determine the cleavage and embryo developmental rates after parthenogenetic activation of cumulus-oocyte complexes (COCs) selected by different concentrations of brilliant cresyl blue (BCB) and cryopreservation. In the first experiment, COCs were separated into groups and incubated for 1 h in medium containing BCB (13 µM, 16 µM, or 20 µM). The control group was not exposed to BCB staining. In the second experiment, COCs were divided into four groups: 13 µM BCB(+), 13 µM BCB(-), fresh control (selected by morphologic observation and immediately in vitro matured) and vitrified control (selected by morphologic evaluation, vitrified, and in vitro matured). In the first experiment, the 13 µM BCB group displayed greater development rates at the morula stage (65.45%, 36/55) when compared with the other groups. In the second experiment, cleavage (47.05%, 72/153) and morula development (33.55%, 51/153) of the control group of fresh COCs were increased compared with the other groups. However, when comparing morula rates between vitrified COC control and BCB(+) groups, the BCB(+) group had better results (19.23%, 5/26 and 64.7%, 11/17, respectively). Our best result in rat COC selection by BCB staining was obtained using a concentration of 13 µM. This selection could be a valuable tool to improve vitrification outcomes, as observed by the BCB(+) group that demonstrated better results compared with the vitrified COC control.
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Técnicas de Maduración In Vitro de los Oocitos , Vitrificación , Ratas , Animales , Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos/fisiología , Oxazinas/farmacologíaRESUMEN
The emergence of multidrug-resistant strains of M. tuberculosis has raised concerns due to the greater difficulties in patient treatment and higher mortality rates. Herein, we revisited the 2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine scaffold and identified potent new carbamate derivatives having MIC90 values of 0.18-1.63â µM against Mtb H37Rv. Compounds 47-49, 51-53, and 55 exhibited remarkable activity against a panel of clinical isolates, displaying MIC90 values below 0.5â µM. In Mtb-infected macrophages, several compounds demonstrated a 1-log greater reduction in mycobacterial burden than rifampicin and pretomanid. The compounds tested did not exhibit significant cytotoxicity against three cell lines or any toxicity to Galleria mellonella. Furthermore, the imidazo[2,1-b][1,3]oxazine derivatives did not show substantial activity against other bacteria or fungi. Finally, molecular docking studies revealed that the new compounds could interact with the deazaflavin-dependent nitroreductase (Ddn) in a similar manner to pretomanid. Collectively, our findings highlight the chemical universe of imidazo[2,1-b][1,3]oxazines and their promising potential against MDR-TB.
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Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Antituberculosos/química , Simulación del Acoplamiento Molecular , Oxazinas/farmacología , Tuberculosis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológicoRESUMEN
Forestry pest management includes biological and chemical methods of pest control. Using insecticides and natural enemies can be compatible in forest pest management programs. The compatibility of the predatory stink bug Podisus distinctus with the insecticide indoxacarb, used in forestry, needs to be evaluated in Brazil. This study investigated the mortality, survival, respiration, preference, prey consumption, and locomotor activity of P. distinctus adults exposed to indoxacarb. In concentration-mortality bioassays, the lethality of indoxacarb (LC50 = 2.62 g L-1 and LC90 = 6.11 g L-1) was confirmed in P. distinctus adults. The survival rate was 100% in predator insects not exposed to indoxacarb, declining to 40.7% in predator insects exposed to 2.62 g L-1 and 0.1% in predators treated with 6.11 g L-1. Indoxacarb reduced the respiration of P. distinctus from 18.45 to 14.41 µL CO2 h-1 at 2.62 g L-1 for up to 3 h after insecticide exposure, inhibiting food consumption and displaying hyperexcitation. The harmful effects of indoxacarb to the natural enemy suggest that it should be better assessed for use with P. distinctus for pest management in forestry.
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Hemípteros , Heterópteros , Insecticidas , Animales , Insecticidas/farmacología , Oxazinas/farmacología , Conducta PredatoriaRESUMEN
OBJECTIVES: The ability of tumor cells to drive angiogenesis is an important cancer hallmark that positively correlates with metastatic potential and poor prognosis. Therefore, targeting angiogenesis is a rational therapeutic approach and dissecting proangiogenic pathways is important, particularly for malignancies driven by oncogenic KRAS, which are widespread and lack effective targeted therapies. Based on published studies showing that oncogenic RAS promotes angiogenesis by upregulating the proangiogenic NF-κB target genes IL-8 and VEGF, that NF-κB activation by KRAS requires the IKKß kinase, and that targeting IKKß reduces KRAS-induced lung tumor growth in vivo, but has limited effects on cell growth in vitro, we hypothesized that IKKß targeting would reduce lung tumor growth by inhibiting KRAS-induced angiogenesis. MATERIALS AND METHODS: To test this hypothesis, we targeted IKKß in KRAS-mutant lung cancer cell lines either by siRNA-mediated transfection or by treatment with Compound A (CmpdA), a highly specific IKKß inhibitor, and used in vitro and in vivo assays to evaluate angiogenesis. RESULTS AND CONCLUSIONS: Both pharmacological and siRNA-mediated IKKß targeting in lung cells reduced expression and secretion of NF-κB-regulated proangiogenic factors IL-8 and VEGF. Moreover, conditioned media from IKKß-targeted lung cells reduced human umbilical vein endothelial cell (HUVEC) migration, invasion and tube formation in vitro. Furthermore, siRNA-mediated IKKß inhibition reduced xenograft tumor growth and vascularity in vivo. Finally, IKKß inhibition also affects endothelial cell function in a cancer-independent manner, as IKKß inhibition reduced pathological retinal angiogenesis in a mouse model of oxygen-induced retinopathy. Taken together, these results provide a novel mechanistic understanding of how the IKKß pathway affects human lung tumorigenesis, indicating that IKKß promotes KRAS-induced angiogenesis both by cancer cell-intrinsic and cancer cell-independent mechanisms, which strongly suggests IKKß inhibition as a promising antiangiogenic approach to be explored for KRAS-induced lung cancer therapy.
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Células Endoteliales/fisiología , Quinasa I-kappa B/metabolismo , Neoplasias Pulmonares/irrigación sanguínea , Oxazinas/farmacología , Piperidinas/farmacología , Piridinas/farmacología , Animales , Línea Celular Tumoral , Movimiento Celular , Humanos , Quinasa I-kappa B/antagonistas & inhibidores , Quinasa I-kappa B/genética , Interleucina-8/genética , Interleucina-8/metabolismo , Neoplasias Pulmonares/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Mutación/genética , FN-kappa B/genética , FN-kappa B/metabolismo , Neovascularización Patológica , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas p21(ras)/genética , ARN Interferente Pequeño/genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Objectives: To describe the distributions of bedaquiline and linezolid MIC values for the Mycobacterium tuberculosis WT population and to define the corresponding epidemiological cut-offs (ECOFFs) in three Latin American countries. Methods: MICs of bedaquiline and linezolid were determined by the resazurin microtitre assay (REMA). In phase 1, interlaboratory reproducibility was assessed using a panel of 10 fully susceptible M. tuberculosis strains. Phase 2 involved MIC determination for 248 clinical isolates from Argentina (n = 58), Brazil (n = 100) and Peru (n = 90) from patients who were treatment-naive for bedaquiline and linezolid. We then determined the ECOFFs for bedaquiline and linezolid by the eyeball method and the ECOFFinder statistical calculator. Results: Phase 1: REMA MIC values in the three sites were either identical to each other or differed by one 2-fold dilution from the consensus value with the exception of a single value. Phase 2: the bedaquiline MIC range was 0.0039-0.25 mg/L for pan-susceptible and drug-resistant isolates combined. The linezolid MIC range was 0.062-0.5 mg/L for pan-susceptible isolates and 0.031-4 mg/L for drug-resistant isolates. ECOFFs were 0.125 mg/L for bedaquiline and 0.50 mg/L for linezolid. Conclusions: REMA is reproducible and robust for the determination of bedaquiline and linezolid MIC distributions and ECOFF values when applied in laboratories of medium/low-resource countries. We suggest that WT MIC distributions for both drugs should be used as a monitoring tool to control the possible rapid emergence of resistance.
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Antituberculosos/farmacología , Diarilquinolinas/farmacología , Linezolid/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Argentina , Brasil , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana , Oxazinas/farmacología , Perú , Valores de Referencia , Reproducibilidad de los Resultados , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Xantenos/farmacologíaRESUMEN
This study reports the antibacterial properties and modulation analysis of antibiotic activity by NaCe(MoO4)2 microcrystals as well as their structural and morphological characterization. Evaluation of the antibacterial and antibiotic-modulating activity was carried out using the broth microdilution method. The Minimum Inhibitory Concentrations (MICs) of the compounds were expressed as the geometric mean of the triplicate values obtained through the use of Resazurin. Compound concentrations in the plates ranged from 512 to 0.5⯵g/mL. Regarding its direct antibacterial activity, NaCe(MoO4)2 had a MICâ¯≥â¯1024⯵g/mL against all studied strains. As for its modulatory effect, it presented synergism with the antibiotic Gentamicin against the S. aureus strain and with Norfloxacin against E. coli, causing a reduction of 75% and 60%, respectively, in the antibiotic quantity required to have the same effect on the strain in study.
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Antibacterianos/farmacología , Cerio/farmacología , Molibdeno/farmacología , Antibacterianos/química , Cerio/química , Química Farmacéutica/métodos , Sinergismo Farmacológico , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Gentamicinas/farmacología , Pruebas de Sensibilidad Microbiana , Molibdeno/química , Nanopartículas , Norfloxacino/farmacología , Oxazinas/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Difracción de Rayos X , Xantenos/farmacologíaRESUMEN
Many countries in Latin America have recently experienced outbreaks of Zika and chikungunya fever, in additional to the usual burden imposed by dengue, all of which are transmitted by Aedes aegypti in this region. To identify potential larvicides, we determined the toxicity of eight modern insecticides to A. aegypti larvae from a colony that originated from field-collected insects in southern Mexico. The most toxic compounds were pyriproxyfen (which prevented adult emergence) and λ-cyhalothrin, followed by spinetoram, imidacloprid, thiamethoxam, and acetamiprid, with chlorantraniliprole and spiromesifen the least toxic products. Field trails performed in an urban cemetery during a chikungunya epidemic revealed that insecticide-treated ovitraps were completely protected from the presence of Aedes larvae and pupae for 6 and 7 weeks in spinosad (Natular G30) and λ-cyhalothrin-treated traps in both seasons, respectively, compared to 5-6 weeks for temephos granule-treated ovitraps, but was variable for pyriproxyfen-treated ovitraps with and 1 and 5 weeks of absolute control in the dry and rainy seasons, respectively. Insecticide treatments influenced the mean numbers of Aedes larvae + pupae in each ovitrap, mean numbers of eggs laid, and percentage of egg hatch over time in both trials. The dominant species was A. aegypti in both seasons, although the invasive vector Aedes albopictus was more prevalent in the rainy season (26.7%) compared to the dry season (10.2%). We conclude that the granular formulation of spinosad (Natular G30) and a suspension concentrate formulation of λ-cyhalothrin proved highly effective against Aedes spp. in both the dry and rainy seasons in the cemetery habitat in this region.
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Aedes/efectos de los fármacos , Fiebre Chikungunya/prevención & control , Dengue/prevención & control , Insectos Vectores/efectos de los fármacos , Insecticidas/farmacología , Larva/efectos de los fármacos , Pupa/crecimiento & desarrollo , Infección por el Virus Zika/prevención & control , Aedes/virología , Animales , Cementerios , Fiebre Chikungunya/transmisión , Fiebre Chikungunya/virología , Dengue/transmisión , Dengue/virología , Combinación de Medicamentos , Insectos Vectores/virología , Macrólidos/farmacología , México , Neonicotinoides/farmacología , Nitrilos/farmacología , Nitrocompuestos/farmacología , Oxazinas/farmacología , Piretrinas/farmacología , Piridinas/farmacología , Compuestos de Espiro/farmacología , Temefós/farmacología , Tiametoxam , Tiazoles/farmacología , Infección por el Virus Zika/transmisión , Infección por el Virus Zika/virología , ortoaminobenzoatos/farmacologíaRESUMEN
Thiamethoxam (TMX) belongs to a class of neuro-active insecticides referred as neonicotinoids, while actara® (AC) is one of the most popular TMX-based products in Brazil. The aim of this study was to evaluate the mutagenic, recombinogenic and carcinogenic potential of TMX and AC insecticides. The mutagenic and recombinogenic effect of TMX and AC were evaluated in vivo by the Somatic Mutation and Recombination Test (SMART) while carcinogenic effects were evaluated through the Test for Detection of Epithelial Tumor Clones (wts test), both in somatic cells of Drosophila melanogaster. In the SMART, third instar larvae from standard (ST) and high bioactivation (HB) crosses were treated with different concentrations of TMX and AC (2.4; 4.8; 9.7 × 10-4 mM and 1.9 × 10-3 mM). The results revealed mutagenic effects at the highest concentrations tested in the HB cross. In the test for the detection of epithelial tumor, third instar larvae resulting from the cross between wts/TM3, Sb1 virgin females and mwh/mwh males were treated with the same concentrations of TMX and AC used in the SMART. No carcinogenic effect was observed at any of the concentrations tested. In this work, the inhibition of the mechanism of repair by homologous recombination was observed in flies exposed to 9.7 × 10-4 and 1.9 × 10-3 mM of AC. In conclusion, TMX and AC demonstrated to be a promutagen in the highest concentrations tested.
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Drosophila melanogaster/efectos de los fármacos , Neonicotinoides/farmacología , Nitrocompuestos/farmacología , Oxazinas/farmacología , Tiazoles/farmacología , Animales , Brasil , Carcinogénesis/efectos de los fármacos , Drosophila melanogaster/citología , Femenino , Insecticidas/farmacología , Masculino , Mutagénesis/efectos de los fármacos , Pruebas de Mutagenicidad/métodos , Recombinación Genética/efectos de los fármacos , TiametoxamRESUMEN
Oxazine derivatives, a class of heterocyclic compounds, exhibit a variety of biological properties, such as anticonvulsant and antitumor activities. In this study, we evaluated the effect of two cyclohexene-fused 1,3-oxazines (cis1-benzyl-N-phenyl-1,4,4a,5,8,8a-hexahydro-3,1-benzoxazin-2-imine (1) and transN-phenyl-1,4,4a,5,8,8a-hexahydro-3,1-benzoxazin-2-imine (2)) in cultures of Bacillus cereus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Salmonella enterica, Serratia marcescens, Shigella flexneri and Staphylococcus aureus by the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). Additionally, the ex vivo antiparasitic activity of oxazines was assessed against Schistosoma mansoni, a helminth that is one of the major agents of the disease schistosomiasis Also, oxazines were evaluated on three tumor cell lines, NCI-H292 (human lung carcinoma), MCF-7 (human breast adenocarcinoma) and HEp-2 (human cervix carcinoma), and two normal cell lines (Vero and red blood cells). Bioassays revealed that oxazine 2 is more effective against bacteria than oxazine 1, with the lowest MIC and MBC values of 3.91 and 32.5µg/mL, respectively. Similarly, compound 2 demonstrated higher antiparasitic activity than 1, and scanning electron microscopy analysis showed several morphological alterations in the tegument of worms in a concentration-dependent manner. In contrast, both oxazines exhibited low cytotoxic effects on cancer and normal cell lines. These results indicated that oxazines exerted direct effects on bacteria and parasite schistosomes. More importantly, since schistosomiasis control programs rely on one drug, praziquantel, oxazines may have the potential to become new antischistosomal agents.
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Antibacterianos/farmacología , Ciclohexenos/farmacología , Oxazinas/farmacología , Esquistosomicidas/farmacología , Animales , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Schistosoma mansoni/efectos de los fármacos , Schistosoma mansoni/ultraestructura , OvinosRESUMEN
PURPOSE: Morphological features of tear microdesiccates on glass surfaces have been associated with tear fluid status. Tear-film lipids play a critical role in the pathophysiology of some ocular surface disorders. Tear microdesiccates display 4 distinctive morphological domains (zones I, II, III, and transition band). In this study, we investigated the lipid location in tear microdesiccates. METHODS: Tear from individual healthy eyes (assessed by symptoms, signs, and slit-lamp examination) was collected using absorbing minisponges. One-µL aliquots were allowed to dry under ambient conditions on microscope slides. Tear microdesiccates were examined by various transmitted light microscopy methods. Tear lipids were located both by partition experiments using 2 lipophilic dyes (Oil red O and Nile blue A) mixed with tear fluid under conditions preserving morphological features of microdesiccates and by assessing the effect of 2 solvents markedly differing in polarity (water and ethanol) on the morphology of particular domains of preformed microdesiccates. RESULTS: During desiccation, both Nile blue A and Oil red O became preferentially located in the outermost domain of tear microdesiccates (zone I) without affecting the formation of major fern-like crystalloids (zones II and III). Low volumes of water drastically affected fern-like crystalloids, whereas the gross morphology of zone I was maintained. Contrarily, ethanol, a less polar solvent, was a fixative for fern-like crystalloids, although it markedly affected the bulk of zone I by extracting liquid droplets out of microdesiccates and visibilizing some filamentous subcomponents. CONCLUSIONS: Zone I is a hydrophobic domain, whereas zones II and III are highly hydrophilic domains of tear microdesiccates. Zone I represents a lipid-rich structure.
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Lípidos/análisis , Lágrimas/química , Adolescente , Compuestos Azo/farmacología , Colorantes/farmacología , Desecación , Femenino , Voluntarios Sanos , Humanos , Masculino , Oxazinas/farmacología , Lágrimas/efectos de los fármacos , Adulto JovenRESUMEN
Small molecules targeting kinases involved in B cell receptor signaling are showing encouraging clinical activity in chronic lymphocytic leukemia (CLL) patients. Fostamatinib (R406) and entospletinib (GS-9973) are ATP-competitive inhibitors designed to target spleen tyrosine kinase (Syk) that have shown clinical activity with acceptable toxicity in trials with CLL patients. Preclinical studies with these inhibitors in CLL have focused on their effect in patient-derived leukemic B cells. In this work we show that clinically relevant doses of R406 and GS-9973 impaired the activation and proliferation of T cells from CLL patients. This effect could not be ascribed to Syk-inhibition given that we show that T cells from CLL patients do not express Syk protein. Interestingly, ζ-chain-associated protein kinase (ZAP)-70 phosphorylation was diminished by both inhibitors upon TCR stimulation on T cells. In addition, we found that both agents reduced macrophage-mediated phagocytosis of rituximab-coated CLL cells. Overall, these results suggest that in CLL patients treated with R406 or GS-9973 T cell functions, as well as macrophage-mediated anti-tumor activity of rituximab, might be impaired. The potential consequences for CLL-treated patients are discussed.
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Indazoles/farmacología , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Macrófagos/inmunología , Oxazinas/farmacología , Pirazinas/farmacología , Piridinas/farmacología , Quinasa Syk/antagonistas & inhibidores , Linfocitos T/efectos de los fármacos , Proteína Tirosina Quinasa ZAP-70/metabolismo , Anciano , Anciano de 80 o más Años , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Femenino , Humanos , Activación de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Fagocitosis/efectos de los fármacos , Fosforilación/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Rituximab/farmacología , Linfocitos T/inmunologíaRESUMEN
Dormancy models for Mycobacterium tuberculosis play important roles in understanding various aspects of tuberculosis pathogenesis and in the testing of novel therapeutic regimens. By simulating the latent tuberculosis infection, in which the bacteria exist in a non-replicative state, the models demonstrate reduced susceptibility to antimycobacterial agents. This minireview outlines the models available for simulating latent tuberculosis both in vitro and in several animal species. Additionally, this minireview discusses the advantages and disadvantages of these models for investigating the bacterial subpopulations and susceptibilities to sterilization by various antituberculosis drugs.
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Antituberculosos/farmacología , Modelos Animales de Enfermedad , Tuberculosis Latente/patología , Mycobacterium tuberculosis/crecimiento & desarrollo , Tuberculosis Pulmonar/patología , Animales , Farmacorresistencia Bacteriana , Cobayas , Indicadores y Reactivos/farmacología , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/microbiología , Macaca fascicularis , Ratones , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , Oxazinas/farmacología , Conejos , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/microbiología , Xantenos/farmacología , Pez CebraRESUMEN
The brown stink bug Euschistus heros is the most abundant species of the soybean-sucking bugs, and causes large economic losses. Applying different chemical groups of organosynthetic insecticides for its control increases the potential for resistance. Esterases are a group of enzymes that play a variety of roles in insects, and some of them are related to the metabolism of xenobiotics. The aim of this study was to analyze the esterase isoenzyme system of this species and investigate its response to Engeo™ Pleno (thiamethoxam and lambda-cyhalothrin), which is the most widely used pesticide in soybean crops. Two strains were analyzed: the EB strain, which had been free of insecticides for several generations; and the MA strain, which was collected in a location exposed to agrochemicals. By analyzing the polyacrylamide gel electrophoresis profile, seven different esterases in adults and nymphs of both strains were found. Eight gene loci were responsible for the synthesis of these enzymes. The differences in esterases between the two strains and enzyme changes in insects exposed to Engeo™ Pleno suggest that EST-2 and EST-4 are related to the metabolism of the agrochemical used and are mechanisms of resistance.
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Esterasas/genética , Hemípteros/enzimología , Proteínas de Insectos/genética , Insecticidas/farmacología , Nitrilos/farmacología , Nitrocompuestos/farmacología , Oxazinas/farmacología , Piretrinas/farmacología , Tiazoles/farmacología , Animales , Inhibidores Enzimáticos/química , Esterasas/antagonistas & inhibidores , Esterasas/metabolismo , Genes de Insecto , Sitios Genéticos , Hemípteros/efectos de los fármacos , Proteínas de Insectos/antagonistas & inhibidores , Proteínas de Insectos/metabolismo , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Dosificación Letal Mediana , Neonicotinoides , Ninfa/efectos de los fármacos , Ninfa/enzimología , Control de Plagas , Especificidad por Sustrato , TiametoxamRESUMEN
Dormancy models for
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Animales , Cobayas , Ratones , Conejos , Antituberculosos/farmacología , Modelos Animales de Enfermedad , Tuberculosis Latente/patología , Tuberculosis Pulmonar/patología , Farmacorresistencia Bacteriana , Indicadores y Reactivos/farmacología , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/microbiología , Macaca fascicularis , Mycobacterium tuberculosis , Mycobacterium tuberculosis/metabolismo , Oxazinas/farmacología , /tratamiento farmacológico , Tuberculosis Pulmonar/microbiología , Xantenos/farmacología , Pez CebraRESUMEN
Dormancy models for
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Animales , Cobayas , Ratones , Conejos , Antituberculosos/farmacología , Modelos Animales de Enfermedad , Tuberculosis Latente/patología , Mycobacterium tuberculosis/crecimiento & desarrollo , Tuberculosis Pulmonar/patología , Farmacorresistencia Bacteriana , Indicadores y Reactivos/farmacología , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/microbiología , Macaca fascicularis , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , Oxazinas/farmacología , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/microbiología , Xantenos/farmacología , Pez CebraRESUMEN
OBJECTIVE: To analyze the neonatal screening program for hemoglobinopathies in São Carlos, Southeast Brazil, by investigating a series of cases in which the screening test was abnormal. More specifically, it was aimed to know the information regarding the neonatal screening received by mothers at the hospital and at primary health care, in addition to information related to genetic counseling. METHODS: A descriptive study that enrolled 119 mothers, accounting for 73% of all children born between 2010 and 2011 with abnormal results of neonatal screening for hemoglobinopathies. The mothers completed a questionnaire that assessed the information received at hospital and primary health care, and issues related to genetic counseling. Descriptive statistics was performed. RESULTS: Of the 119 participating mothers, 69 (58%) had children with sickle cell trait, 22 (18.5%) with hemoglobin C trait, 18 (15.1%) with alpha thalassemia trait and, in 10 cases (8.4%), the result was inconclusive. At the hospital, 118 mothers (99.2%) received information about where to go to collect the test and 115 (96.6%) were informed about the correct time to collect the test. Only 4 mothers (3.4%) were informed about which diseases are investigated and the risks of not performing the screening. Seventeen mothers (14.3%) recognized the difference between trait and disease, and 42 (35.3%) considered that a positive screening test could have implications for future pregnancies. In 70 cases (58.8%), the child's physician was not informed about the screening test results. CONCLUSIONS: The neonatal screening program needs further improvement. In both scenarios investigated, health professionals demonstrated a lack of training in providing information to mothers and families. .
OBJETIVO: Fazer uma análise do programa de triagem neonatal de hemoglobinopatias no município de São Carlos, São Paulo, Brasil, por meio da investigação de série de casos cujo resultado do teste de rastreio foi alterado. Objetivou-se conhecer as informações a respeito da triagem neonatal recebidas pelas mães na maternidade e na atenção primária à saúde, além das informações relacionadas à orientação genética. MÉTODOS: Estudo descritivo, no qual participaram 119 mães cujos filhos apresentaram teste de triagem de hemoglobinopatia alterado, o que correspondeu a 73% das crianças nascidas entre 2010 e 2011 com resultado de triagem neonatal para hemoglobinopatia anormal. As mães responderam um questionário que avaliou informações recebidas na maternidade e na atenção primária à saúde, além de aspectos relacionados à orientação genética. Foi feita estatística descritiva dos dados. RESULTADOS: Das 119 mães participantes, 69 (58%) tinham filhos com traço falciforme, 22 (18,5%) traço C, 18 (15,1%) traço alfatalassêmico e 10 (8,4%) resultado inconclusivo. Na maternidade, 118 mães (99,2%) receberam informação sobre onde ir e 115 (96,6%) foram orientadas sobre o momento correto para coleta do teste. Somente quatro mães (3,4%) foram informadas sobre quais doenças seriam investigadas e os riscos de não fazer o rastreio. Das 119 mães participantes, 17 (14,3%) reconheceram a diferença entre traço e doença e 42 (35,3%) consideraram que um teste alterado poderia ter implicações para futuras gestações. Em 70 casos (58,8%), o médico da criança não foi informado sobre o resultado da triagem. CONCLUSÕES: O programa de triagem neonatal necessita de aperfeiçoamento. Nos dois cenários investigados, os profissionais de saúde carecem de treinamento para orientar mães e famílias. .
Asunto(s)
Antimaláricos/farmacología , Oxazinas/farmacología , Plasmodium falciparum/efectos de los fármacos , Piridinas/farmacología , Antimaláricos/síntesis química , Antimaláricos/metabolismo , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxazinas/síntesis química , Oxazinas/metabolismo , Pruebas de Sensibilidad Parasitaria , Piridinas/síntesis química , Piridinas/metabolismo , Relación Estructura-ActividadRESUMEN
The aim of the present study was to examine the effects of brilliant cresyl blue (BCB) staining on mitochondrial functions in porcine oocytes. Cumulus-oocyte complexes (COCs) collected from slaughterhouse-derived porcine ovaries were cultured with (13 µM) or without (0 µM, control) BCB for 60 min. Mitochondrial functions in oocytes were examined immediately after staining or after in vitro maturation. The BCB-stained oocytes produced reactive oxygen species (ROS) at higher levels than control oocytes immediately after staining (2.2-fold, P < 0.001) and after maturation (1.7-fold, P < 0.001). The adenosine triphosphate (ATP) content and mitochondrial membrane potential (MMP) in oocytes were similar for the two groups immediately after staining. However, ATP and relative MMP levels were significantly (P < 0.05) lower in BCB-treated oocytes than in the control (2.18 versus 2.83 pM and 0.82 versus 1.0, respectively). There was no difference in mitochondrial DNA copy number between the two groups after maturation. The ATP content in early developmental stage embryos (3 days after parthenogenetic activation) was lower in the BCB-stained group than that in the control group but the difference was not significant. In conclusion, BCB staining of oocytes at the immature stage compromises mitochondrial functions throughout oocyte maturation, but function is restored during early embryo development.
Asunto(s)
Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Oocitos/metabolismo , Oxazinas/farmacología , Coloración y Etiquetado/métodos , Adenosina Trifosfato/metabolismo , Animales , Cromatina/metabolismo , ADN Mitocondrial/metabolismo , Femenino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Oocitos/química , Oocitos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Sus scrofaRESUMEN
Recently, we have provided evidence for the involvement of a cytosolic tyrosine-phosphorylatable 70 kDa oocyte protein in Rhinella arenarum (Anura: Bufonidae) fertilization. The aim of the present work was to characterize its phosphorylation, determine the identity of this protein and establish its biological role during the fertilization process. Tyrosine phosphorylation of the 70 kDa protein was not observed in eggs activated with the calcium ionophore A23187. Pretreatment of oocytes with the tyrosine kinase inhibitor genistein effectively blocked the fertilization-dependent phosphorylation of the 70 kDa protein. In order to identify this protein, we examined the presence in amphibian oocytes of non-receptor 70 kDa tyrosine kinase members of the Syk/Zap70 and Tec families by RT-PCR using degenerate primers. We found that R. arenarum oocytes contain the transcripts coding for Syk and Tec kinases. Western blot analysis confirmed the presence of Syk protein in unfertilized oocytes and eggs. Studies using phospho-Syk specific antibodies showed that fertilization rapidly (less than 10 minutes) induces phosphorylation on Syk tyrosine residues (352 and 525/526) that are necessary for the activation of the enzyme. Finally, specific inhibition of Syk with the R406 compound provoked a diminished fertilization score, thereby confirming a functional role of the Syk protein during R. arenarum fertilization. To our knowledge this is the first time that Syk is described as a player in the signaling cascade activated after fertilization.
Asunto(s)
Fertilización/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Oocitos/metabolismo , Óvulo/fisiología , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Animales , Bufonidae , Calcimicina/farmacología , Activación Enzimática , Femenino , Genisteína/farmacología , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Oxazinas/farmacología , Fosforilación/efectos de los fármacos , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Piridinas/farmacología , Transducción de Señal , Quinasa Syk , Proteína Tirosina Quinasa ZAP-70/genética , Proteína Tirosina Quinasa ZAP-70/metabolismoRESUMEN
Cisplatin resistance remains one of the major obstacles when treating epithelial ovarian cancer. Because oxaliplatin and nedaplatin are effective against cisplatin-resistant ovarian cancer in clinical trials and signal transducer and activator of transcription 3 (STAT3) is associated with cisplatin resistance, we investigated whether overcoming cisplatin resistance by oxaliplatin and nedaplatin was associated with the STAT3 pathway in ovarian cancer. Alamar blue, clonogenic, and wound healing assays, and Western blot analysis were used to compare the effects of platinum drugs in SKOV-3 cells. At an equitoxic dose, oxaliplatin and nedaplatin exhibited similar inhibitory effects on colony-forming ability and greater inhibition on cell motility than cisplatin in ovarian cancer. Early in the time course of drug administration, cisplatin increased the expression of pSTAT3 (Tyr705), STAT3α, VEGF, survivin, and Bcl-XL, while oxaliplatin and nedaplatin exhibited the opposite effects, and upregulated pSTAT3 (Ser727) and STAT3ß. The STAT3 pathway responded early to platinum drugs associated with cisplatin resistance in epithelial ovarian cancer and provided a rationale for new therapeutic strategies to reverse cisplatin resistance.