Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732135

RESUMEN

Glioblastoma (GBM) is the most lethal and common malignant primary brain tumor in adults. An important feature that supports GBM aggressiveness is the unique composition of its extracellular matrix (ECM). Particularly, fibronectin plays an important role in cancer cell adhesion, differentiation, proliferation, and chemoresistance. Thus, herein, a hydrogel with mechanical properties compatible with the brain and the ability to disrupt the dynamic and reciprocal interaction between fibronectin and tumor cells was produced. High-molecular-weight hyaluronic acid (HMW-HA) functionalized with the inhibitory fibronectin peptide Arg-Gly-Asp-Ser (RGDS) was used to produce the polymeric matrix. Liposomes encapsulating doxorubicin (DOX) were also included in the hydrogel to kill GBM cells. The resulting hydrogel containing liposomes with therapeutic DOX concentrations presented rheological properties like a healthy brain. In vitro assays demonstrated that unmodified HMW-HA hydrogels only caused GBM cell killing after DOX incorporation. Conversely, RGDS-functionalized hydrogels displayed per se cytotoxicity. As GBM cells produce several proteolytic enzymes capable of disrupting the peptide-HA bond, we selected MMP-2 to illustrate this phenomenon. Therefore, RGDS internalization can induce GBM cell apoptosis. Importantly, RGDS-functionalized hydrogel incorporating DOX efficiently damaged GBM cells without affecting astrocyte viability, proving its safety. Overall, the results demonstrate the potential of the RGDS-functionalized hydrogel to develop safe and effective GBM treatments.


Asunto(s)
Doxorrubicina , Fibronectinas , Glioblastoma , Ácido Hialurónico , Hidrogeles , Oligopéptidos , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Doxorrubicina/farmacología , Doxorrubicina/química , Oligopéptidos/química , Oligopéptidos/farmacología , Fibronectinas/metabolismo , Fibronectinas/antagonistas & inhibidores , Hidrogeles/química , Línea Celular Tumoral , Ácido Hialurónico/química , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Liposomas/química , Apoptosis/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/metabolismo
2.
Placenta ; 139: 99-111, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37354692

RESUMEN

INTRODUCTION: The mechanisms that govern fibroblast behavior during the vascular adaptations of the uterus at early pregnancy remain unknown. Anandamide, an endocannabinoid, binds to cannabinoid receptors (CBs), and regulates gestation and angiogenesis. Its tone is regulated by fatty acid amide hydrolase (FAAH) within the uterus. We investigated the role of anandamide in endometrial fibroblasts migration and whether anandamide modulates fibroblasts-endothelial crosstalk. METHODS: T-hESC and EA.hy926 cell lines were used as models of endometrial stromal and endothelial cells, respectively. T-hESC were incubated with anandamide plus different agents. Migration was tested (wound healing assay and phalloidin staining). Protein expression and localization were studied by Western blot and immunofluorescence. To test fibroblast-endothelial crosstalk, EA.hy926 cells were incubated with fibroblast conditioned media obtained after T-hESC migration. RESULTS: Anandamide 1 nM increased T-hESC migration via CB1 and CB2. Cyclooxygenase-2 participated in anandamide-stimulated fibroblast migration. Prostaglandin F2alpha, and not prostaglandin E2, increased fibroblast wound closure. CB1, CB2, cyclooxygenase-2 and FAAH were expressed in T-hESC. Anandamide did not alter cyclooxygenase-2 localization but induced its cytoplasmic and nuclear expression through CB1 and CB2. URB-597, a FAAH selective inhibitor, also increased T-hESC migration via both CBs, and augmented cyclooxygenase-2 expression. Conditioned media from anandamide-induced T-hESC wound healing closure stimulated endothelial migration and did not alter their proliferation. Soluble factors from cyclooxygenase-2 were secreted by T-hESC and participated in T-hESC-induced EA.hy926 migration. Although anandamide-conditioned media augmented in EA.hy926 the expression of γH2AX, a marker of DNA damage, cyclooxygenase-2 was not involved in this effect. DISCUSSION: Our results provide novel evidence about an active role of anandamide on endometrial fibroblast behavior as a mechanism regulating uterine vascular adaptations in early gestation.


Asunto(s)
Endocannabinoides , Células Endoteliales , Embarazo , Femenino , Humanos , Endocannabinoides/farmacología , Células Endoteliales/metabolismo , Medios de Cultivo Condicionados , Prostaglandina-Endoperóxido Sintasas , Fibroblastos/metabolismo , Amidohidrolasas/genética , Amidohidrolasas/metabolismo
3.
Ophthalmol Ther ; 12(1): 485-500, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36495395

RESUMEN

INTRODUCTION: Characterization of 2-year progression of different risk phenotypes in eyes with mild and moderate nonproliferative diabetic retinopathy (NPDR) in type 2 diabetes (T2D). METHODS: A 2-year prospective longitudinal cohort study (CORDIS, NCT03696810) was conducted. Ophthalmological examinations were performed including best corrected visual acuity, color fundus photography and optical coherence tomography (OCT and OCTA). OCT metrics, central retinal thickness and ganglion cell layer + inner plexiform layer (GCL + IPL) thickness were analyzed. OCTA metrics, vessel density (VD), perfusion density (PD) and area of intercapillary spaces (AIS) were obtained from superficial and deep capillary plexus (SCP, DCP). Only phenotype C identified by decreased VD ≥ 2 SD of healthy controls and phenotype B identified by subclinical macular edema with decreased VD < 2 SD of healthy controls were included. RESULTS: One hundred twenty-two eyes from T2D individuals were included in study; 65 eyes (53%) were classified as phenotype B and 57 eyes (47%) as phenotype C. For phenotype B, progression was associated with thinning of the GCL + IPL (ETDRS 35, 1 year p = 0.013, 2 year p < 0.001; ETDRS 43-47, 2 year p = 0.003) and vessel closure involving mainly the DCP for both ETDRS grades (ETDRS 35, 1 year p = 0.025, 2 year p = 0.034; ETDRS 43-47, 1 year p = 0.011). For phenotype C there was also progressive thinning of the GCL + IPL (ETDRS 35, in both years p ≤ 0.001; ETDRS 43-47, 1 year p = 0.002, 2 year p = 0.001), with vessel closure involving mainly SCP (ETDRS 35, 1 year p = 0.012, 2 year p = 0.023 in full-retina), which appeared to stabilize at maximal values in ETDRS grade 43-47 at the end of 2 years. ETDRS severity changes at the end of the 2-year period showed that worsening was associated with phenotype C with changes involving predominantly the SCP (VD, p = 0.005; PD, p = 0.008; AIS, p = 0.005). CONCLUSIONS: Association between ETDRS classification of NPDR severity and identification of different risk phenotypes offers new perspective to predict disease progression in T2D individuals with NPDR.

4.
Reproduction ; 163(2): 85-94, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34990399

RESUMEN

Implantation-related events are crucial for pregnancy success. In particular, defects in vascular remodeling at the maternal-fetal interface are associated with spontaneous miscarriage and recurrent pregnancy loss. Physical activity and therapies oriented to reduce stress improve pregnancy outcomes. In animal models, environmental stimulation and enrichment are associated with enhanced well-being, cognitive function and stress resilience. Here, we studied whether the exposure of BALB/c mice to an enriched environment (EE) regulates crucial events during early gestation at the maternal-fetal interface. Pregnant BALB/c mice were exposed to the EE that combines non-invasive stimuli from the sensory pathway with voluntary physical activity. The pregnancy rate was evaluated. Implantation sites were investigated microscopically and macroscopically. Vascular adaptation parameters at the maternal-fetal interface were analyzed. We found that exposure to the EE prevented pregnancy loss between gestational days 7 and 15. Also, it increased the diameter of the uterine artery and decreased the wall:lumen ratio of the mesometrial decidual vessels, suggesting that EE exposure promotes vascular remodeling. Moreover, it increased nitric oxide synthase activity and inducible nitric oxide synthase expression, as well as prostaglandin F2a production and endoglin expression in the implantation sites. Exposure of pregnant females to the EE regulates uterine physiology, promoting vascular remodeling during early gestation. These adaptations might contribute to preventing embryo loss. Our results highlight the importance of the maternal environment for pregnancy success. The design of an 'EE-like' protocol for humans could be considered as a new non-pharmacologic strategy to prevent implantation failure and recurrent miscarriage.


Asunto(s)
Pérdida del Embrión , Remodelación Vascular , Animales , Decidua/metabolismo , Femenino , Humanos , Exposición Materna , Ratones , Ratones Endogámicos BALB C , Embarazo , Útero/metabolismo
5.
Reproduction ; 159(2): R55-R67, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31426027

RESUMEN

Lysophosphatidic acid (LPA) belongs to the group of phosphorylated lipids reported as crucial mediators in the physiology of reproduction. LPA binds to G-protein-coupled receptors and regulates a wide range of female reproductive functions. This bioactive lipid has also been implicated in vascular functions during physiological and pathological conditions. In this regard, the establishment of a successful pregnancy requires proper coordination of vascular processes and remodeling of maternal blood vessels during early gestation. During this process, first trimester cytotrophoblast changes from an invasive to an endovascular phenotype and transforms uterine spiral arteries which are the nutrient supply for placenta and fetus. Here we present an overview of LPA participation in vascular remodeling and highlight the importance of LPA-LPA3 signaling during early gestation at the maternal-fetal interface.

6.
J Cell Physiol ; 234(5): 6274-6285, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30362520

RESUMEN

Spiral artery remodeling at the maternal-fetal interface is crucial for successful pregnancy and requires the interaction between the first trimester trophoblast and the endothelial cells of the maternal vessels. However, the precise mechanism of this dialog has yet to be determined. The current study investigated whether lysophosphatidic acid (LPA) modulates trophoblast-endothelial crosstalk in vitro. HTR-8/SVneo trophoblast cell line (H8) was seeded on top of Geltrex, incubated with LPA or LPA + NS-398 (selective cyclooxygenase-2 inhibitor), LPA + 1400W (selective inducible nitric oxide synthase inhibitor) or LPA + IL-6 neutralizing antibody and assayed for tube formation to model the acquisition of trophoblast endovascular phenotype. The supernatants were collected and used as conditioned media (CM). To test trophoblast-endothelial crosstalk, the endothelial cell line EA.hy926 was incubated with trophoblast CM. The CM from LPA-induced tubulogenesis stimulated endothelial cells migration and did not modify the apoptosis. Soluble factors derived from cyclooxygenase-2 and IL-6 pathways were involved in H8-EA.hy926 interaction under the LPA effect. Moreover, LPA increased the levels of IL-6 mRNA by cyclooxygenase-2 pathway in H8 cells. Collectively, LPA promotes trophoblast-endothelial crosstalk in vitro and induces the release of trophoblast soluble factors that stimulate endothelial cells migration without changes in apoptosis. The evidence presented here provides new insights about an active role of LPA as a lipid mediator regulating vascular remodeling at the maternal-fetal interface.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Lisofosfolípidos/farmacología , Placentación/efectos de los fármacos , Placentación/fisiología , Trofoblastos/efectos de los fármacos , Línea Celular , Femenino , Humanos , Neovascularización Fisiológica/efectos de los fármacos , Neovascularización Fisiológica/fisiología , Embarazo , Receptor Cross-Talk/efectos de los fármacos , Receptor Cross-Talk/fisiología , Trofoblastos/metabolismo
7.
Mol Cell Endocrinol ; 478: 126-132, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30099013

RESUMEN

Successful implantation and placentation requires that extravillous cytotrophoblast acquires an endovascular phenotype and remodels uterine spiral arteries. Progesterone (P4) and estradiol (E2) control many of the placental functions, but their role in vascular remodeling remains controversial. Here, we investigated whether P4 and E2 regulate the acquisition of the human first trimester trophoblast endovascular phenotype, and the participation of the lysophosphatidic acid pathway. For this purpose, human first trimester HTR-8/SVneo cells were seeded on Geltrex and assayed for capillary-like tube formation. P4 and E2 increased HTR-8/SVneo tube formation in a concentration-dependent manner and this effect is mediated by the LPA3 receptor. Moreover, sex steroids increased the mRNA levels of the main enzyme that produce lysophosphatidic acid (lysophospholipase-D) but did not regulate LPA3 mRNA levels. Overall, we demonstrate that steroid hormones regulate HTR-8/SVneo trophoblast capillary-like structures formation and we propose that this process could be modulated directly or indirectly by mechanisms associated to the LPA/LPA3 pathway.


Asunto(s)
Lisofosfolípidos/metabolismo , Primer Trimestre del Embarazo/metabolismo , Esteroides/farmacología , Trofoblastos/citología , Trofoblastos/metabolismo , Línea Celular , Estradiol/farmacología , Femenino , Humanos , Neovascularización Fisiológica/efectos de los fármacos , Hidrolasas Diéster Fosfóricas/genética , Hidrolasas Diéster Fosfóricas/metabolismo , Embarazo , Progesterona/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Trofoblastos/efectos de los fármacos
8.
J Cell Biochem ; 119(1): 758-772, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28657680

RESUMEN

Successful implantation and placentation requires that extravillous cytotrophoblast acquires an endovascular phenotype and remodels uterine spiral arteries. Defects in this mechanism correlate with severe obstetric complications as implantation failure and preeclampsia. Lysophosphatidic acid (LPA) participates in embryo implantation and contributes to vascular physiology in different biological systems. However, the role of LPA on trophoblast endovascular transformation has not been studied. Due to difficulties in studying human pregnancy in vivo, we adopted a pharmacological approach in vitro to investigate LPA action in various aspects of trophoblast endovascular response, such as the formation of endothelial capillary-like structures, migration, and proliferation. The HTR-8/SVneo cell line established from human first trimester cytotrophoblast was used to model the acquisition of the endovascular phenotype by the invading trophoblast. LPA increased HTR-8/SVneo tube formation, migration (wound healing assay and phalloidin staining) and proliferation (MTT assay). LPA G protein-coupled receptors, LPA1 and LPA3 , were expressed in HTR-8/SVneo. By using selective antagonists, we showed that enhanced tubulogenesis was mediated by LPA3 . In addition, cyclooxygenase-2 and inducible nitric oxide synthase pathways participated in LPA-stimulated tubulogenesis. Inducible nitric oxide synthase was activated downstream cyclooxygenase-2. Furthermore, prostaglandin E2 and a nitric oxide donor (SNAP) increased trophoblast tube formation in a concentration-dependent manner. Finally, we observed that cyclooxygenase-2 and inducible nitric oxide synthase were localized in the nucleus, and LPA did not modify their cellular distribution. Our results show that LPA-triggered regulatory pathways promote trophoblast endovascular response in vitro, suggesting a new role for LPA during spiral artery remodeling at the maternal-fetal interface.


Asunto(s)
Lisofosfolípidos/farmacología , Placentación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Trofoblastos/citología , Línea Celular , Núcleo Celular/metabolismo , Ciclooxigenasa 2/metabolismo , Femenino , Humanos , Técnicas In Vitro , Fenotipo , Embarazo , Trofoblastos/metabolismo
9.
Reprod Fertil Dev ; 29(11): 2112-2126, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28376314

RESUMEN

Lysophosphatidic acid (LPA) affects several female reproductive functions through G-protein-coupled receptors. LPA contributes to embryo implantation via the lysophospholipid LPA3 receptor. In the present study we investigated the participation of endogenous LPA signalling through the LPA3 receptor in vascularisation and decidualisation, two crucial events at the maternal-fetal interface. Pregnant rats were treated with diacylglycerol pyrophosphate (DGPP), a highly selective antagonist of LPA3 receptors, on Day 5 of gestation. Pregnant rats received intrauterine (i.u.) injections of single doses of DGPP (0.1mgkg-1) in a total volume of 2µL in the left horn (treated horn) in the morning of GD5. DGPP treatment produced aberrant embryo spacing and increased embryo resorption. The LPA3 receptor antagonist decreased the cross-sectional length of the uterine and arcuate arteries and induced histological anomalies in the decidua and placentas. Marked haemorrhagic processes, infiltration of immune cells and tissue disorganisation were observed in decidual and placental tissues from sites of resorption. The mRNA expression of three vascularisation markers, namely interleukin 10 (Il10), vascular endothelial growth factor (Vegfa) and vascular endothelial growth factor receptor 1 (Vegfr1), was reduced at sites of resorption from Day 8. The results show that the disruption of endogenous LPA signalling by blocking the LPA3 receptor modified the development of uterine vessels with consequences in the formation of the decidua and placenta and in the growth of embryos.


Asunto(s)
Decidua/metabolismo , Lisofosfolípidos/metabolismo , Neovascularización Fisiológica/fisiología , Placenta/metabolismo , Receptores del Ácido Lisofosfatídico/metabolismo , Transducción de Señal/fisiología , Animales , Decidua/efectos de los fármacos , Difosfatos/farmacología , Implantación del Embrión/fisiología , Femenino , Glicerol/análogos & derivados , Glicerol/farmacología , Interleucina-10/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Placenta/irrigación sanguínea , Placenta/efectos de los fármacos , Embarazo , Ratas , Receptores del Ácido Lisofosfatídico/agonistas , Transducción de Señal/efectos de los fármacos , Arteria Uterina/efectos de los fármacos , Arteria Uterina/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo
10.
Stem Cell Reports ; 5(6): 1053-1066, 2015 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-26549847

RESUMEN

Pyruvate kinase deficiency (PKD) is a rare erythroid metabolic disease caused by mutations in the PKLR gene. Erythrocytes from PKD patients show an energetic imbalance causing chronic non-spherocytic hemolytic anemia, as pyruvate kinase defects impair ATP production in erythrocytes. We generated PKD induced pluripotent stem cells (PKDiPSCs) from peripheral blood mononuclear cells (PB-MNCs) of PKD patients by non-integrative Sendai viral vectors. PKDiPSCs were gene edited to integrate a partial codon-optimized R-type pyruvate kinase cDNA in the second intron of the PKLR gene by TALEN-mediated homologous recombination (HR). Notably, we found allele specificity of HR led by the presence of a single-nucleotide polymorphism. High numbers of erythroid cells derived from gene-edited PKDiPSCs showed correction of the energetic imbalance, providing an approach to correct metabolic erythroid diseases and demonstrating the practicality of this approach to generate the large cell numbers required for comprehensive biochemical and metabolic erythroid analyses.


Asunto(s)
Anemia Hemolítica Congénita no Esferocítica/genética , Anemia Hemolítica Congénita no Esferocítica/terapia , Células Eritroides/citología , Células Madre Pluripotentes Inducidas/metabolismo , Piruvato Quinasa/deficiencia , Piruvato Quinasa/genética , Errores Innatos del Metabolismo del Piruvato/genética , Errores Innatos del Metabolismo del Piruvato/terapia , Alelos , Secuencia de Bases , Recuento de Células , ADN Complementario/genética , Células Eritroides/metabolismo , Marcación de Gen , Terapia Genética , Humanos , Leucocitos Mononucleares/metabolismo , Recombinación Genética
11.
São Paulo; SMS; 2015. [9] p. tab, graf.
No convencional en Portugués | Sec. Munic. Saúde SP, CRSNORTE-Producao, Sec. Munic. Saúde SP, Sec. Munic. Saúde SP | ID: sms-9784

RESUMEN

Documenta a importância de instrumentos analíticos na Gestão da Assistência Farmacêutica para a padronização de processos e organização dos serviços farmacêuticos, bem como mostra como a aplicação desses instrumentos podem contribuir de maneira significativa para a melhoria da qualidade dos serviços farmacêuticos ofertados no Sistema Único de Saúde.


Asunto(s)
Humanos , Farmacia , Servicios Farmacéuticos , Farmacia/instrumentación , Farmacia/métodos , Farmacia/organización & administración , Servicios Farmacéuticos/organización & administración , Servicios Farmacéuticos/normas , Servicios Farmacéuticos
12.
Cancer Res ; 74(1): 56-67, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24310398

RESUMEN

Accurate preclinical predictions of the clinical efficacy of experimental cancer drugs are highly desired but often haphazard. Such predictions might be improved by incorporating elements of the tumor microenvironment in preclinical models by providing a more physiological setting. In generating improved xenograft models, it is generally accepted that the use of primary tumors from patients are preferable to clonal tumor cell lines. Here we describe an interdisciplinary platform to study drug response in multiple myeloma, an incurable cancer of the bone marrow. This platform uses microfluidic technology to minimize the number of cells per experiment, while incorporating three-dimensional extracellular matrix and mesenchymal cells derived from the tumor microenvironment. We used sequential imaging and a novel digital imaging analysis algorithm to quantify changes in cell viability. Computational models were used to convert experimental data into dose-exposure-response "surfaces," which offered predictive utility. Using this platform, we predicted chemosensitivity to bortezomib and melphalan, two clinical multiple myeloma treatments, in three multiple myeloma cell lines and seven patient-derived primary multiple myeloma cell populations. We also demonstrated how this system could be used to investigate environment-mediated drug resistance and drug combinations that target it. This interdisciplinary preclinical assay is capable of generating quantitative data that can be used in computational models of clinical response, demonstrating its utility as a tool to contribute to personalized oncology.


Asunto(s)
Antineoplásicos/farmacología , Mieloma Múltiple/tratamiento farmacológico , Línea Celular Tumoral , Simulación por Computador , Humanos , Técnicas Analíticas Microfluídicas , Modelos Biológicos , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Células del Estroma/patología , Microambiente Tumoral/efectos de los fármacos
13.
J Pediatr Hematol Oncol ; 35(2): e77-80, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22935660

RESUMEN

Neonatal cyanosis in healthy newborns can be associated either with methemoglobin due to cytochrome b5 reductase deficiency or to M-hemoglobin, a group of hemoglobin variants resulting from mutations in the globin chain genes. We report the clinical case of a neonate with cyanosis and normal cardiac and respiratory function. At birth the hematological parameters were normal; however, the methemoglobinemia was 16%. Spontaneously, the cyanosis gradually decreased and by the fifth month of age the methemoglobin level was normal. A heterozygous Gγ-globin gene (HBG2) missense mutation 87 C-A (Leu28Met) was identified. His father, with a history of transfusion in the neonatal period, is heterozygous for the same mutation. This hemoglobin variant, not previously described, was called Hb F Viseu and is the sixth Gγ-chain variant reported in association with neonatal cyanosis.


Asunto(s)
Cianosis/etiología , Hemoglobina Fetal/genética , Hemoglobina M/genética , Hemoglobinas Anormales/genética , Humanos , Recién Nacido , Masculino , Metahemoglobina/análisis
14.
J Environ Sci Health B ; 47(10): 949-58, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22938579

RESUMEN

This study reports the influence of sugar cane vinasse on the persistence, sorption and leaching potential of diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea), hexazinone (3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4-dione) and tebuthiuron (1-(5-tert-butyl-1,3,4-thiadiazol-2-yl)-1,3-dimethylurea) in both a clay and sandy soil from a tropical area of Brazil. The experiments were conducted out under controlled laboratory conditions. The addition of sugarcane vinasse to soil influenced the persistence and sorption of the herbicides in both the studied clay and sandy soils, with a considerable decrease in the diuron DT50 values in clay soil. The Ground Water Ubiquity Score (GUS) Index classifies the herbicides as leachers in both soils and treatments, with the exception of diuron, which is classified as a non-leacher in clay soil-vinasse and as a transient herbicide in sandy soil. These results suggest that special attention should be given to areas such as those where the sandy soil was collected in this study, which is a recharge area of the Guarani Aquifer and is likely to experience groundwater contamination due to the high leaching potential of the applied pesticides.


Asunto(s)
Monitoreo del Ambiente/métodos , Herbicidas/química , Saccharum/química , Contaminantes del Suelo/química , Adsorción , Brasil
15.
Pesticidas ; 21: 103-116, jan.-out. 2011. tab, graf
Artículo en Portugués | LILACS | ID: lil-671119

RESUMEN

O uso inadequado de pesticidas na agricultura tem sido apontado como fonte de risco para a saúde humana e para o ambiente. Considerando que os recursos hídricos são os principais destinos desses compostos após a aplicação, este trabalho apresenta a otimização e validação de dois métodos analíticos simples e efi cientes para a determinação de pesticidas em águas superfi ciais e subterrâneas. Foram selecionados os pesticidas mais aplicados no município de Dourados, (Mato Grosso – Brasil) com intensa atividade agrícola. Efetuou-se a pré-concentração por extração em fase sólida com cartucho C18 (500 mg) e eluição com metanol para as amostras analisadas por cromatografi a a líquido de alta eficiência com detector espectrofotométrico na região do ultravioleta (CLAE/UV) (2,4-D e 2,4-DCF) e com acetato de etila:diclorometano (1:1, v/v) para as analisadas por cromatografi a a gás com detector termiônico específi co (CG/DTE) (atrazina, DIA, DEA, trifluralina e parationa metílica). Os métodos apresentaram exatidão (76-107%) e precisão (<12%) satisfatórias para as substâncias nos níveis de fortifi cação selecionados, exceto para DIA (<51%), assim como para o estudo de estabilidade dos pesticidas (-20ºC por até 21 dias). Os limites de quantificação dos métodos (0,22 - 0,48 μg L-1) estão de acordo com a legislação brasileira vigente para pesticidas em água. Embora somente o 2,4-D tenha sido detectado em dois pontos de coleta no período estudado, alerta-se para a necessidade de avaliação sistemática da presença de pesticidas em água para consumo humano, particularmente, em regiões com intensa atividade agrícola. Tal monitoramento pode fornecer subsídios para políticas públicas ambientais.


Asunto(s)
Agua Potable/análisis , Ambiente , Riesgos Ambientales , Plaguicidas/efectos adversos , Plaguicidas/toxicidad
16.
Transfusion ; 51(3): 570-3, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20738827

RESUMEN

BACKGROUND: The RHD gene is highly polymorphic and a large number of D variants have already been detected. Several mechanisms are involved in the origin of D variants. In-frame deletions, resulting in a single-amino-acid deletion, have been described associated with RhD and RhCE variants. No in-frame duplications and/or insertions have been reported in the RH genes to date. STUDY DESIGN AND METHODS: Blood samples from a Brazilian blood donor and his sister were serologically tested with routine anti-D reagents and anti-D panels (ALBAclone advanced partial D typing kit, Alba Bioscience Limited; and D-Screen, Diagast), followed by molecular biology techniques, RHD polymerase chain reaction with sequence-specific priming and sequencing. RESULTS: Samples tested negative with routine immunoglobulin M (IgM) anti-D reagents and positive with IgG anti-D, which detect weak D cells. The pattern of results with anti-D panels did not correspond to any described before. A 3-bp in-frame duplication within Exon 1 (c.75_77dupTCT), resulting in the duplication of leucine 26 (p.Leu26dup), was identified in the two samples. CONCLUSION: We report the first RhD variant associated with a 3-bp in-frame duplication in the RHD gene, predicted to be located within the RhD protein transmembrane domain that might be expected to result in a weak-D-like phenotype, concordant with serologic findings.


Asunto(s)
Duplicación de Gen , Sistema del Grupo Sanguíneo Rh-Hr/genética , Exones , Variación Genética , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Sistema del Grupo Sanguíneo Rh-Hr/inmunología
17.
Reprod Biomed Online ; 18(2): 209-18, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19192341

RESUMEN

Anandamide is an endocannabinoid known to participate in reproductive processes. This study observed that 17beta-oestradiol and progesterone modulated the production of anandamide and its metabolizing enzymes in the rat uterus. Anandamide production was highest at the oestrous stage and 17beta-oestradiol and progesterone stimulated its synthesis in ovariectomized rats. During early pregnancy, anandamide production remained constant on days 1-5 of gestation and diminished towards day 6. On day 6, implantation sites showed lower synthesis compared with interimplantation sites. In the delayed implantation model, 17beta-oestradiol inhibited anandamide synthesis compared with progesterone. During pseudopregnancy, anandamide production did not decrease towards day 6 as occurred during normal gestation. The administration of 17beta-oestradiol augmented anandamide production in rats on day 5 of pseudopregnancy; the treatment with mifepristone did not produce any change in anandamide synthesis. Anandamide-metabolizing enzymes were regulated by progesterone and 17beta-oestradiol. The effect of ovarian hormones on the synthesis of anandamide depends on different physiological conditions, oestrous cycle and early pregnancy, and on the presence of the activated blastocyst. Thus, ovarian hormones, as signals that emanate from the mother, operate in conjunction with the blastocyst intrinsic programme, regulating the synthesis of anandamide in a specific manner during crucial reproductive events that may compromise pregnancy outcome.


Asunto(s)
Ácidos Araquidónicos/biosíntesis , Estradiol/farmacología , Progesterona/farmacología , Útero/efectos de los fármacos , Amidohidrolasas/genética , Amidohidrolasas/metabolismo , Animales , Moduladores de Receptores de Cannabinoides/biosíntesis , Implantación del Embrión/efectos de los fármacos , Implantación del Embrión/genética , Endocannabinoides , Ciclo Estral/efectos de los fármacos , Ciclo Estral/genética , Ciclo Estral/metabolismo , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Ovariectomía , Fosfolipasa D/genética , Fosfolipasa D/metabolismo , Alcamidas Poliinsaturadas , Embarazo , Seudoembarazo/genética , Seudoembarazo/metabolismo , Ratas , Ratas Wistar , Factores de Tiempo , Útero/metabolismo
18.
J Chromatogr Sci ; 46(7): 585-90, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18718132

RESUMEN

Residues of the herbicides simazine, metribuzin, metolachlor, trifluralin, atrazine, and two metabolites of atrazine, deisopropylatrazine (DIA) and deethylatrazine (DEA), are surveyed in the surface and groundwater of the Primavera do Leste region, Mato Grosso, Brazil during September and December 1998 and April 1999. Different water source sampling stations of groundwater (irrigation water well, drinking water well, and water hole) and surface water (dam and river) are set up based on agricultural land use. A solid-phase extraction procedure followed by gas chromatography-nitrogen-phosphorus detection is used for the determination of these compounds. All compounds are detected at least once in water samples. A temporal trend of pesticide contamination is observed, with the highest contamination frequency occurring in December during the main application season. Metribuzin shows the highest individual detection frequencies throughout the monitoring period, followed by metolachlor, simazine, and DEA. The maximum mean concentrations of pesticides in this study are in the range from 0.14 to 1.7 microg/L. We deduct that the contamination of water resources is predominantly caused by non-point pollution of pesticides used in intensive cash-crop cultures of the Cerrado area. Therefore, a continuous monitoring of pesticide concentrations in water resources of this tropical region is necessary to detect the longer term contamination trends and developing health risks.


Asunto(s)
Residuos de Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Acetamidas/análisis , Agricultura , Atrazina/análisis , Brasil , Cromatografía de Gases/métodos , Simazina/análisis , Extracción en Fase Sólida , Triazinas/análisis , Trifluralina/análisis , Abastecimiento de Agua/análisis
19.
Biochim Biophys Acta ; 1782(2): 82-9, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18078830

RESUMEN

Macrophages (Mps) are essential cellular components of the innate immune system. They are released from the bone marrow as immature monocytes and after circulating in the blood stream, migrate into tissues to undergo final differentiation into resident Mps. In general terms Mps behavior in breast tumors, was described as being either for or against tumor growth. Under certain well defined circumstances Mps are able to kill cells in two ways: direct tumor cytotoxicity or antibody dependent cytotoxicity. We had previously demonstrated that peritoneal Mps from LMM3 mammary tumor bearing mice (TMps) enhanced in vivo the LMM3 induced angiogenesis, promoting tumor growth while Mps from normal BALB/c mice (NMps) did not. In this work, we demonstrate that Mps, expressing functional muscarinic acetylcholine receptors, are able to proliferate in vitro in response to the muscarinic agonist carbachol. These peritoneal cells use two distinct metabolic pathways: TMps are primed by tumor presence and they proliferate mainly by activating arginase pathway and by producing high levels of prostaglandin E(2) via M(1)-M(3) receptors activation. In NMps, carbachol stimulates M(2) receptors function, triggering protein kinase C activity and induces moderate prostaglandin E(2) liberation via M(1) receptor.


Asunto(s)
Adenocarcinoma/patología , Proliferación Celular , Macrófagos Peritoneales/metabolismo , Neoplasias Mamarias Experimentales/patología , Receptores Muscarínicos/fisiología , Adenocarcinoma/enzimología , Adenocarcinoma/metabolismo , Animales , Arginasa/fisiología , Carbacol/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/enzimología , Macrófagos Peritoneales/patología , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/metabolismo , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias/patología , Prostaglandina-Endoperóxido Sintasas/fisiología , Proteína Quinasa C/fisiología , Receptores Muscarínicos/metabolismo
20.
J Environ Sci Health B ; 42(6): 697-705, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17701705

RESUMEN

Persistent organic pollutants (POPs), organochlorine pesticides and polychlorinated biphenyls (PCBs), listed as per the Stockholm Convention (alpha -HCH, beta -HCH, gamma -HCH, p,p'-DDT, o,p'-DDT, p,p'-DDD, p,p'-DDE, aldrin, endrin, dieldrin, PCBs 28, 52, 118, 138, 153, and 180), were analyzed in municipal solid waste (MSW) compost samples from three different Brazilian composting plants located in three São Paulo State cities: Araras, Araraquara and São Paulo (Vila Leopoldinha). Quantitative and qualitative analyses were carried out using gas chromatography electron capture detection (GC-ECD) and gas chromatography mass spectrometry (GC-MS) (Ion Trap, electron impact ionization), respectively. The samples were analyzed in triplicate and the target POPs were not detected by GC-ECD. Twelve pollutants were identified in two samples when qualitative analysis (GC-MS) was used (beta -HCH, gamma -HCH, p,p'-DDT, o,p'-DDT, p,p'-DDD, and p,p'-DDE, PCBs 28, 118, 138, 153 and 180). The composting process has advantages such as urban solid waste reduction and landfill life-span increase, however the MSW compost quality, which can be utilized for agricultural purposes, should be evaluated and be controlled. This kind of study is the first step in making available information to answer questions regarding MSW compost for sustainable agricultural use, such as the pollutants accumulation in soil and in groundwater, and plants uptake.


Asunto(s)
Contaminantes Ambientales/análisis , Hidrocarburos Clorados/análisis , Residuos de Plaguicidas/análisis , Bifenilos Policlorados/análisis , Residuos/análisis , Brasil , Cromatografía de Gases/métodos , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Plaguicidas/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...