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1.
Bioinformatics ; 34(21): 3776-3778, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29850773

RESUMO

Summary: TomoEED is an optimized software tool for fast feature-preserving noise filtering of large 3D tomographic volumes on CPUs and GPUs. The tool is based on the anisotropic nonlinear diffusion method. It has been developed with special emphasis in the reduction of the computational demands by using different strategies, from the algorithmic to the high performance computing perspectives. TomoEED manages to filter large volumes in a matter of minutes in standard computers. Availability and implementation: TomoEED has been developed in C. It is available for Linux platforms at http://www.cnb.csic.es/%7ejjfernandez/tomoeed. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Computadores , Software , Tomografia Computadorizada por Raios X , Algoritmos
2.
Eur J Nutr ; 56(1): 89-97, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26450601

RESUMO

PURPOSE: Serum nitric oxide (NO) reduction and increased endothelin-1 (ET-1) play a pivotal role in endothelial dysfunction and hypertension. Considering that traditional Mediterranean diet (TMD) reduces blood pressure (BP), the aim of this study was to analyze whether TMD induced changes on endothelial physiology elements such as NO, ET-1 and ET-1 receptors which are involved in BP control. METHODS: Non-smoking women with moderate hypertension were submitted for 1 year to interventions promoting adherence to the TMD, one supplemented with extra virgin olive oil (EVOO) and the other with nuts versus a control low-fat diet (30 participants/group). BP, NO, ET-1 and related gene expression as well as oxidative stress biomarkers were measured. RESULTS: Serum NO and systolic BP (SBP) or diastolic BP (DBP) were negatively associated at baseline, as well as between NO and ET-1. Our findings also showed a DBP reduction with both interventions. A negative correlation was observed between changes in NO metabolites concentration and SBP or DBP after the intervention with TMD + EVOO (p = 0.033 and p = 0.044, respectively). SBP reduction was related to an impairment of serum ET-1 concentrations after the intervention with TMD + nuts (p = 0.008). We also observed changes in eNOS, caveolin 2 and ET-1 receptors gene expression which are related to NO metabolites levels and BP. CONCLUSIONS: The changes in NO and ET-1 as well as ET-1 receptors gene expression explain, at least partially, the effect of EVOO or nuts on lowering BP among hypertensive women.


Assuntos
Biomarcadores/sangue , Pressão Sanguínea , Dieta Mediterrânea , Hipertensão/sangue , Nozes , Azeite de Oliva/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Índice de Massa Corporal , Peso Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dieta com Restrição de Gorduras , Endotelina-1/sangue , Feminino , Regulação da Expressão Gênica , Humanos , Hipertensão/dietoterapia , Estilo de Vida , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Receptor de Endotelina A/sangue , Receptor de Endotelina A/genética , Fatores de Risco , Inquéritos e Questionários , Triglicerídeos/sangue , Circunferência da Cintura
3.
Opt Express ; 24(4): 3790-805, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-27333621

RESUMO

NOMAD is a suite of three spectrometers that will be launched in 2016 as part of the joint ESA-Roscosmos ExoMars Trace Gas Orbiter mission. The instrument contains three channels that cover the IR and UV spectral ranges and can perform solar occultation, nadir and limb observations, to detect and map a wide variety of Martian atmospheric gases and trace species. Part I of this work described the models of the UVIS channel; in this second part, we present the optical models representing the two IR channels, SO (Solar Occultation) and LNO (Limb, Nadir and Occultation), and use them to determine signal to noise ratios (SNRs) for many expected observational cases. In solar occultation mode, both the SO and LNO channel exhibit very high SNRs >5000. SNRs of around 100 were found for the LNO channel in nadir mode, depending on the atmospheric conditions, Martian surface properties, and observation geometry.

4.
Br J Biomed Sci ; 72(3): 120-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26510268

RESUMO

Pulsed-field gel electrophoresis (PFGE) is the 'gold standard' for genotyping of methicillin-resistant Staphylococcus aureus (MRSA); however, the DiversiLab (DL) system, based on rep-PCR, is faster, simpler and could be better adapted to daily routine hospital work. We genotyped 100 MRSA isolates using PFGE, DL, and spa typing, and evaluated the discriminatory power of each technique and the correlation between them by Simpson's index(SI) and adjusted Rand coefficient (ARI), respectively. The isolates were from clinical samples from eight hospitals in Extremadura (Spain) during 2010. DL separated the 100 MRSA into 18 patterns, with 69% of the isolates grouped into four predominant patterns. spa typing reported 17 spa types, classifying 69% of MRSA into two major types (t067 and t002). PFGE revealed the existence of 27 patterns, gathering 54% of MRSA into three pulse types (E8a, E7a and E7b). SI values were 0.819, 0.726, 0.887 and 0.460 for DL, spa typing, PFGE and CC-BURP, respectively. ARI values of DL over PFGE, spa typing and CC-BURP were 0.151, 0.321 and 0.071, respectively. DL has less discriminatory power than PFGE but more than spa typing. The concordance of DL with PFGE is low, primarily because DL does not discriminate between the three predominant MRSA pulse types in our environment.


Assuntos
Antígenos de Bactérias/genética , Técnicas de Tipagem Bacteriana/normas , Genótipo , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Técnicas de Tipagem Bacteriana/métodos , Eletroforese em Gel de Campo Pulsado/métodos , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Repetições de Microssatélites , Filogenia , Reação em Cadeia da Polimerase/métodos , Infecções Estafilocócicas/microbiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-36427427

RESUMO

Specialized pro-resolvin mediators (SPMs) are a superfamily of bioactive molecules synthesized from polyunsaturated fatty acids (arachidonic, eicosapentaenoic and docosahexaenoic acids) that include resolvins, protectins and maresins. These metabolites are important to control the resolution phase of inflammation and the epithelial repair, which is essential in restoring the mucosal barriers. Unfortunately, the effects of SPMs on intestinal epithelial cell growth remain poorly understood. Caco-2 cell were used as intestinal epithelial cell model. Cell growth/DNA synthesis, cell signalling pathways, western blot and wound repair assay were performed. Our data demonstrated that SPMs such as lipoxin LxA4, resolvin (Rv) E1, RvD1, protectin D 1 and maresin 1 were able to enhance intestinal epithelial Caco-2 cell growth and DNA synthesis. Furthermore, our results provide evidence that these effects of RvE1 and RvD1 were associated with a pertussis toxin-sensitive G protein-coupled receptor, and that leukotriene B4 receptor 2 could be involved, at least in part, in these effects of RvE1/RvD1. Moreover, these mitogenic effects induced by SPMs were dependent on the ERK 1/2 and p38 MAPK pathways as well as phospholipase C and protein kinase C activation. Thus, these mitogenic effects of RvE1/RvD1 on intestinal epithelial cells could be involved in this signalling circuit involved in wounded epithelium and the catabasis process.


Assuntos
Ácidos Graxos , Intestinos , Humanos , Células CACO-2 , Proliferação de Células , Técnicas de Cultura de Células , DNA
6.
J Geophys Res Planets ; 127(5): e2021JE007083, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35865508

RESUMO

The Nadir and Occultation for MArs Discovery (NOMAD) instrument suite aboard ExoMars/Trace Gas Orbiter spacecraft is mainly conceived for the study of minor atmospheric species, but it also offers the opportunity to investigate surface composition and aerosols properties. We investigate the information content of the Limb, Nadir, and Occultation (LNO) infrared channel of NOMAD and demonstrate how spectral orders 169, 189, and 190 can be exploited to detect surface CO2 ice. We study the strong CO2 ice absorption band at 2.7 µm and the shallower band at 2.35 µm taking advantage of observations across Martian Years 34 and 35 (March 2018 to February 2020), straddling a global dust storm. We obtain latitudinal-seasonal maps for CO2 ice in both polar regions, in overall agreement with predictions by a general climate model and with the Mars Express/OMEGA spectrometer Martian Years 27 and 28 observations. We find that the narrow 2.35 µm absorption band, spectrally well covered by LNO order 189, offers the most promising potential for the retrieval of CO2 ice microphysical properties. Occurrences of CO2 ice spectra are also detected at low latitudes and we discuss about their interpretation as daytime high altitude CO2 ice clouds as opposed to surface frost. We find that the clouds hypothesis is preferable on the basis of surface temperature, local time and grain size considerations, resulting in the first detection of CO2 ice clouds through the study of this spectral range. Through radiative transfer considerations on these detections we find that the 2.35 µm absorption feature of CO2 ice clouds is possibly sensitive to nm-sized ice grains.

7.
J Geophys Res Planets ; 127(9): e2022JE007231, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36583097

RESUMO

We present water vapor vertical distributions on Mars retrieved from 3.5 years of solar occultation measurements by Nadir and Occultation for Mars Discovery onboard the ExoMars Trace Gas Orbiter, which reveal a strong contrast between aphelion and perihelion water climates. In equinox periods, most of water vapor is confined into the low-middle latitudes. In aphelion periods, water vapor sublimated from the northern polar cap is confined into very low altitudes-water vapor mixing ratios observed at the 0-5 km lower boundary of measurement decrease by an order of magnitude at the approximate altitudes of 15 and 30 km for the latitudes higher than 50°N and 30-50°N, respectively. The vertical confinement of water vapor at northern middle latitudes around aphelion is more pronounced in the morning terminators than evening, perhaps controlled by the diurnal cycle of cloud formation. Water vapor is also observed over the low latitude regions in the aphelion southern hemisphere (0-30°S) mostly below 10-20 km, which suggests north-south transport of water still occurs. In perihelion periods, water vapor sublimated from the southern polar cap directly reaches high altitudes (>80 km) over high southern latitudes, suggesting more effective transport by the meridional circulation without condensation. We show that heating during perihelion, sporadic global dust storms, and regional dust storms occurring annually around 330° of solar longitude (L S) are the main events to supply water vapor to the upper atmosphere above 70 km.

8.
Nature ; 438(7069): 785-91, 2005 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-16319827

RESUMO

On the basis of previous ground-based and fly-by information, we knew that Titan's atmosphere was mainly nitrogen, with some methane, but its temperature and pressure profiles were poorly constrained because of uncertainties in the detailed composition. The extent of atmospheric electricity ('lightning') was also hitherto unknown. Here we report the temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface. In the upper part of the atmosphere, the temperature and density were both higher than expected. There is a lower ionospheric layer between 140 km and 40 km, with electrical conductivity peaking near 60 km. We may also have seen the signature of lightning. At the surface, the temperature was 93.65 +/- 0.25 K, and the pressure was 1,467 +/- 1 hPa.

9.
Biochem Pharmacol ; 190: 114663, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34161796

RESUMO

12(S)-hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT) is an unusual product of the cyclooxygenase pathway that is an endogenous ligand of the low-affinity receptor for leukotriene 4 (LTB4), BLT2. Recent findings suggested that BLT2 possibly plays an important role in the healing of intestinal lesions and the regulation of barrier function. Here, we studied the role of 12-HHT on intestinal epithelial cell growth and the paracellular permeability of intestinal epithelium using Caco-2 cell cultures as experimental model. Our results demonstrated that 12-HHT stimulates intestinal epithelial Caco-2 cell growth through 12-HHT-BLT2-p38-PKC axis and improves paracellular permeability in differentiated Caco-2 cell cultures through the regulation of tight junction elements such as myosin light chain phosphorylation through 12-HHT-BLT2-p38-PKC-MYPT1 axis. Thus, 12-HHT-BLT2 interaction can be involved in intestinal epithelial cell growth and consequently in the epithelium regeneration/repair processes, together with an interesting improvement on the paracellular permeability. These effects appoint that 12-HHT/BLT2 axis may be a suitable strategy for treating wound healing epithelium and barrier-disrupted intestinal processes.


Assuntos
Ácidos Graxos Insaturados/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores do Leucotrieno B4/metabolismo , Células CACO-2 , Proliferação de Células , Células Epiteliais , Ácidos Graxos Insaturados/química , Humanos , Mucosa Intestinal/citologia , Estrutura Molecular , Fosfatase de Miosina-de-Cadeia-Leve/genética , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosforilação , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Receptores do Leucotrieno B4/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Neurocirugia (Astur) ; 21(6): 467-77, 2010 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-21165544

RESUMO

UNLABELLED: INTRODUCTION. Suitable approach to anterior cranial base is mandatory to get global satisfactory surgical outcomes. In the beginning it depends on the exactly anatomical position into the cranial fossa and tridimensional spread. Surgical approach implies the evaluation of the patient status, reconstructive options and surgical team experience. Subcranial approach is a safe surgical option in the treatment of frontal traumatic pathology. It allows adequate management of frontal sinus and its obliteration with easy radiologic follow-up. OBJECTIVES. To analyse subcranial approach as a treatment option in traumatic pathology of the anterior cranial base and to present our review of subcranial approach. Valuation of surgical technical aspects. and related complications. MATERIAL AND METHODS. Retrospective analysis of 50 patients operated (subcranial approach) from January 2004 to December 2009 by Maxillofacial and Neurosurgery Department, University Hospital 12 de Octubre, Madrid. 34 patients presented craniofacial trauma or postraumatic sequela and 16 patients presented craniofacial tumours. Oncological cases offers experience to discuss surgical aspects. Results are related to traumatic pathology and sequela. Main items review were surgical technique including materials used for frontal sinus obliteration, associated traumatic pathology, hospital stay and complication rates. RESULTS. No perioperatory mortality was found. Patients´ age ranged 15-76 years. 22 were male and 12 female. Description of frontal fractures involved. Frontal sinus obliteration was made with calvarian bone dust. Morbidity rates was 29% in posttraumatic patients. Mean hospital stay was 13 days. CONCLUSIONS: Subcranial approach to anterior cranial base is a safe and reliable treatment option to the pathology of this area. It allows outstanding exposure of the nasal cavity, orbits, ethmoidal cells-sphenoid sinus and great access to anterior fossa without frontal lobe retraction.


Assuntos
Fossa Craniana Anterior/cirurgia , Ossos Faciais , Procedimentos Neurocirúrgicos/métodos , Base do Crânio/cirurgia , Adolescente , Adulto , Idoso , Traumatismos Craniocerebrais/cirurgia , Ossos Faciais/patologia , Ossos Faciais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
Science ; 355(6332): 1392-1395, 2017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28325842

RESUMO

The Rosetta spacecraft spent ~2 years orbiting comet 67P/Churyumov-Gerasimenko, most of it at distances that allowed surface characterization and monitoring at submeter scales. From December 2014 to June 2016, numerous localized changes were observed, which we attribute to cometary-specific weathering, erosion, and transient events driven by exposure to sunlight and other processes. While the localized changes suggest compositional or physical heterogeneity, their scale has not resulted in substantial alterations to the comet's landscape. This suggests that most of the major landforms were created early in the comet's current orbital configuration. They may even date from earlier if the comet had a larger volatile inventory, particularly of CO or CO2 ices, or contained amorphous ice, which could have triggered activity at greater distances from the Sun.

12.
Science ; 354(6319): 1566-1570, 2016 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-27856849

RESUMO

The Rosetta spacecraft has investigated comet 67P/Churyumov-Gerasimenko from large heliocentric distances to its perihelion passage and beyond. We trace the seasonal and diurnal evolution of the colors of the 67P nucleus, finding changes driven by sublimation and recondensation of water ice. The whole nucleus became relatively bluer near perihelion, as increasing activity removed the surface dust, implying that water ice is widespread underneath the surface. We identified large (1500 square meters) ice-rich patches appearing and then vanishing in about 10 days, indicating small-scale heterogeneities on the nucleus. Thin frosts sublimating in a few minutes are observed close to receding shadows, and rapid variations in color are seen on extended areas close to the terminator. These cyclic processes are widespread and lead to continuously, slightly varying surface properties.

13.
Rev Esp Quimioter ; 28(2): 79-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25904514

RESUMO

Genotyping methods are useful resources for the surveillance, detection, prevention and control of multidrug-resistant nosocomial agents, such as methicillin-resistant Staphylococcus aureus (MRSA). An understanding of the association between genotype and antibiotic susceptibility in MRSA clones may be useful in the surveillance of MRSA and to avoid inappropriate treatment future resistance. We genotyped MRSA clinical isolates from the Extremadura region of Spain using pulsed field electrophoresis (PFGE) and analyzed the spectrum of antibiotic susceptibility for each isolate to determine whether resistance is associated with specific genotypes. PFGE revealed six major genotypes: E8a (25%), E7b (17%), E7a (12%), E8B (8%), E10 (6%), and E20 (4%). Isolates with the genotypes E8a and E10 exhibit higher resistance ratios for levofloxacin than isolates with the other major pulsotypes. Similar results were obtained for isolates with the E20 pulsotype with respect to mupirocin. Although we identified no vancomycin-, tigecycline-, linezolid- or daptomycin-resistant strains, we observed significant differences in the mean MIC values obtained for some of these drugs among the major genotypes. Specifically, isolates with the E7b, E8b, and E20 genotypes have signif-icantly higher MICs of tigecycline, vancomycin and linezolid, respectively, than the most sensitive pulsotypes. Isolates with the E8b profile also exhibit a significantly higher rate of re-duced vancomycin susceptibility (RVS) (i.e., MIC between 1 and 2 mg/L) than clones with the E10 and E8a profiles. In conclusion, we report associations between genotype and antibiotic sensitivity that should be considered in programs for monitor-ing and controlling MRSA in health care settings.


Assuntos
Farmacorresistência Bacteriana/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Meios de Cultura , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Testes de Sensibilidade Microbiana
14.
Int J Biochem Cell Biol ; 28(4): 465-72, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9026357

RESUMO

The present study investigated the role of kinases and G-proteins in arachidonic acid (AA) mobilization by resident mouse peritoneal macrophages in response to phagocytosis of opsonized zymosan. Stimulation of resident murine peritoneal macrophages with opsonized zymosan caused an increase in [3H] arachidonic acid release. This increase was dose-dependent and was not accompanied by de novo synthesis of proteins. Neither staurosporine, a protein kinase C inhibitor, nor genistein, a tyrosine kinase inhibitor, had any effect on [3H] AA mobilization, although trifluoperazine significantly inhibited AA release. The involvement of G proteins and phospholipase C (PLC) in the regulation of arachidonic acid release induced by opsonized zymosan was also examined in mouse peritoneal macrophages. Prior treatment of cells with pertussis toxin induced a partial decrease in AA mobilization. However, neomycin or aspirin, at doses that inhibit inositol phosphate formation (PLC activity), did not [3H] AA mobilization by PLA2. We proposed that the AA release by peritoneal macrophages in response to opsonized zymosan phagocytosis could be due to the participation of enzymes other than PLC and PKC, or proteins other than G proteins.


Assuntos
Ácido Araquidônico/metabolismo , Proteínas de Ligação ao GTP/fisiologia , Macrófagos Peritoneais/efeitos dos fármacos , Fagocitose/fisiologia , Fosfotransferases/fisiologia , Zimosan/farmacologia , Análise de Variância , Animais , Aspirina/farmacologia , Células Cultivadas , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Neomicina/farmacologia , Toxina Pertussis , Fatores de Virulência de Bordetella/farmacologia
15.
Biochem Pharmacol ; 61(7): 811-6, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11274966

RESUMO

Recently, we suggested that arachidonic acid and/or its cyclooxygenase pathway metabolites may be involved in regulating 3T6 fibroblast proliferation. In the present study we evaluate the role of high-molecular phospholipase A2 (PLA2) enzymes in the 3T6 fibroblast growth. Our results demonstrate that the cytosolic PLA2 inhibitor, arachidonyl trifluoromethylketone and the cytosolic calcium-independent PLA2 (iPLA2) inhibitor, bromoenol lactone, decrease arachidonic acid release and prostaglandin E2 production in 3T6 fibroblast cultures stimulated by fetal calf serum. These effects were correlated with the impairment of 3T6 fibroblast proliferation and DNA synthesis at the S/G2 boundary, which prolongs the S phase. These data suggest a role of iPLA2 in the control of 3T6 fibroblast growth.


Assuntos
Proteínas Sanguíneas/farmacologia , Fibroblastos/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/citologia , Camundongos , Peso Molecular
16.
Biochem Pharmacol ; 44(7): 1437-41, 1992 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-1417964

RESUMO

The anti-inflammatory synthetic polypeptides referred to as antiflammins are thought to be inhibitors of phospholipase A2 (PLA2) (EC 3.1.1.4). These peptides are from the sequence of amino acids of greatest similarity between uteroglobin and lipocortin I. The effect of these peptides was studied on PLA2 activation in rat platelets and on acute inflammatory models after local or parenteral administration of drug. We found that antiflammins decreased collagen-induced platelet activation, but had no effect when arachidonic acid was used as activator. The peptides were able to inhibit acute inflammatory processes induced by carrageenan or phorbol esters when administered locally or parenterally. However, antiflammins had no effect on inflammation induced by exogenous PLA2 administration. These results indicate that the antiflammins may have a direct inhibitory effect on PLA2 activation but not on the enzyme or enzyme-substrate interaction.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Uteroglobina/farmacologia , Sequência de Aminoácidos , Animais , Anti-Inflamatórios , Anti-Inflamatórios não Esteroides/administração & dosagem , Ácido Araquidônico , Carragenina , Colágeno , Dexametasona/farmacologia , Cetoprofeno/farmacologia , Masculino , Camundongos , Dados de Sequência Molecular , Fosfolipases A/antagonistas & inibidores , Fosfolipases A/química , Fosfolipases A2 , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Tromboxano B2/análise
17.
Biochem Pharmacol ; 59(7): 865-70, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10718345

RESUMO

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the present study was to investigate the effects of resveratrol, a polyphenol present in most red wines, on reactive oxygen species formation as well as on arachidonic acid (AA) release, cyclooxygenase expression, and PG synthesis in murine resident peritoneal macrophages. Results show that resveratrol exerted a strong inhibitory effect on superoxide radical (O2-) and hydrogen peroxide (H2O2) produced by macrophages stimulated by lipopolysaccharides (LPS) or phorbol esters (PMA). Resveratrol also significantly decreased [3H]AA release induced by LPS and PMA or by exposure to O2- or H2O2. Resveratrol treatment caused a significant impairment of cyclooxygenase-2 (COX-2) induction stimulated by LPS and PMA or by O2- or H2O2 exposure. These effects of resveratrol on [3H]AA release and COX-2 overexpression were correlated with a marked reduction of PG synthesis. Our results indicate that the antioxidant action of resveratrol affects AA mobilization and COX-2 induction.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonoides , Macrófagos Peritoneais/efeitos dos fármacos , Prostaglandinas/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Estilbenos/farmacologia , Animais , Antioxidantes/farmacologia , Ciclo-Oxigenase 2 , Peróxido de Hidrogênio/metabolismo , Técnicas In Vitro , Isoenzimas/biossíntese , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Fenóis/farmacologia , Polímeros/farmacologia , Polifenóis , Prostaglandina-Endoperóxido Sintases/biossíntese , Resveratrol , Acetato de Tetradecanoilforbol/farmacologia
18.
Biochem Pharmacol ; 50(3): 347-53, 1995 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-7646536

RESUMO

Antiflammins are synthetic peptides with sequence homology to proteins inhibitory for phospholipase A2 (EC 3.1.1.4). The effect of antiflammin 2 on murine arachidonate or 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear oedema has been studied. Topical application of arachidonic acid (AA) produced a short-lived oedema response with rapid onset associated with marked increases in prostaglandin E2 levels. TPA produced a longer-lasting oedema associated with marked influx of neutrophils and mononuclear cells as well as predominant formation of leukotriene B4 (LTB4). Topical pretreatment with indomethacin or dexamethasone reduced plasma leakage, oedema and prostaglandin E2 biosynthesis in AA-induced oedema, whereas antiflammin 2 had no effect. However, topical pretreatment with antiflammin 2 dose-dependently reduced plasma leakage, cell influx, oedema and LTB4 levels in response to TPA. These results indicate that the anti-inflammatory effect of antiflammins can be attributed to AA mobilization and/or 5 lipoxygenase inhibition but can be dissociated from an effect on arachidonic acid metabolism by the cyclooxygenase pathway.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Otopatias/prevenção & controle , Edema/prevenção & controle , Eicosanoides/biossíntese , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Acetilglucosaminidase/metabolismo , Administração Cutânea , Animais , Ácido Araquidônico , Permeabilidade Capilar/efeitos dos fármacos , Dexametasona/farmacologia , Dinoprostona/metabolismo , Otopatias/induzido quimicamente , Otopatias/metabolismo , Edema/induzido quimicamente , Edema/metabolismo , Indometacina/farmacologia , Leucotrieno B4/metabolismo , Masculino , Camundongos , Peroxidase/metabolismo , Acetato de Tetradecanoilforbol
19.
Biochem Pharmacol ; 58(5): 877-9, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10449199

RESUMO

The accumulation of neutrophils and mononuclear cells is a characteristic feature of 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear edema. This cell influx was accompanied by the enhancement of eicosanoid tissue levels and prostaglandin H synthase-2 (PGHS-2) overexpression. Sialidase treatment, which affects the structure of selectins and inhibits leukocyte influx, significantly reduced eicosanoid and PGHS-2 levels and edema. In contrast, skin PGHS-2 overexpression induced by arachidonic acid (AA) application was not affected by sialidase treatment. These results suggest that PGHS-2 overexpression induced by TPA could be induced by AA and/or AA metabolite release by leukocyte infiltrated during the inflammatory process.


Assuntos
Ácido Araquidônico/farmacologia , Isoenzimas/biossíntese , Leucócitos/fisiologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Pele/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Doença Aguda , Animais , Transporte Biológico , Carcinógenos/farmacologia , Quimiotaxia de Leucócito , Ciclo-Oxigenase 2 , Dermatite/enzimologia , Dermatite/imunologia , Fármacos Dermatológicos/farmacologia , Edema/enzimologia , Edema/etiologia , Camundongos , Pele/enzimologia
20.
Biochem Pharmacol ; 56(6): 759-61, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9751081

RESUMO

Several synthetic interleukin-1 (IL-1) peptides were tested in vivo for pyrogenic activity and in vivo for their ability to stimulate prostaglandin production. Only the IL-1beta fragment (208-240) enhanced body temperature, although both IL-1beta (208-240) and IL-1alpha (223-250) stimulated prostaglandin E2 (PGE2) production in vitro. We report here that the IL-1beta fragment (208-240) did not have the capacity to induce arachidonic acid (AA) mobilization by 3T6 fibroblasts. However, this peptide was able to increase the expression of the inducible prostaglandin H synthase isoform (PGHS-2; EC 1.14.99.1.), which is related to its ability to stimulate prostaglandin E2 synthesis.


Assuntos
Dinoprostona/biossíntese , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Interleucina-1/farmacologia , Fragmentos de Peptídeos/farmacologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Animais , Ácido Araquidônico/metabolismo , Células Cultivadas , Indução Enzimática , Fibroblastos/enzimologia , Camundongos
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