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1.
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.

2.
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
3.
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.

4.
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
5.
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
6.
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.

7.
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
8.
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.

9.
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.

10.
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
11.
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
12.
Rev Esp Quimioter ; 27(3): 180-9, 2014 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-25229373

RESUMO

The correct surveillance and control of infection caused by methicillin-resistant Staphylococcus aureus (MRSA) needs of update knowledge of its specific properties in each place. Our study aims to describe the current characteristics of infection due to MRSA in Extremadura. During 2010, 309 MRSA were collected from clinical samples in our region. A susceptibility test that included 17 antibiotics tested by AST -588 card Vitek 2 ® and E -test method was performed on all isolates. A sample of 100 strains, selected by stratified random sampling, were genotyped by pulsed field electrophoresis (PFGE). The prevalence of MRSA in Extremadura was 20.2%. Don Benito-Villanueva area showed the most prevalence and a higher incidence. Merida reported the most favourable situation, with a relatively low ratios of prevalence and incidence. The community acquired reached 44 % in the region, showing predominantly in less populated areas (Navalmoral and Coria). The most common multiresistant pattern was tobramycin-levofloxacin-erythromycin (44%), followed tobramycin-erythromycin-clindamycin (20%). No linezolid, daptomycin and tigecycline resistant strains were observed, but 42 % of the MRSA strains showed decreased susceptibility vancomycin (DSV). PFGE analysis reported 27 genotypes, with 3 major genotypes: E8a (25%), E7b (17%) and E7a (12%). The post-hoc statistical analysis did not reveal significant differences in the distribution of genotypes between different areas. However it revealed some trends that should be considered.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Inquéritos Epidemiológicos , Humanos , Incidência , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Espanha/epidemiologia , Resistência a Vancomicina
13.
Int J Biochem Cell Biol ; 45(7): 1318-26, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23583294

RESUMO

The loss of epithelial barrier function plays a crucial role in the pathogenesis of inflammatory bowel disease, with levels of 5-lipoxygenase metabolites being increased in the mucosa of these patients. The objective of this study was to determine the effect of the eicosanoids produced by the 5-lipoxygenase pathway, leukotriene B4 and D4, and 5-hydroxyeicosatetraenoic acid on epithelial barrier function. Paracellular permeability was estimated from fluorescein isothiocyanate-dextran fluxes and transepithelial electrical resistance in differentiated Caco-2 cells. Our results suggest that leukotriene D4 and 5-hydroxyeicosatetraenoic acid altered both parameters. Identification of the receptors involved in these changes indicated that cysteinyl-leukotriene receptor 1 participates in the effects of leukotriene D4. For both eicosanoids, these effects were mediated by activation of the phospholipase C/Ca(2+)/protein kinase C pathway, in addition to cAMP-independent protein kinase A activation. Furthermore, we observed a correlation between increased paracellular permeability and the redistribution of occludin, and for leukotriene D4, the disorganization of the subapical actin ring and myosin light chain kinase activation. In conclusion, on the basis of our results, we propose that 5-lipoxygenase pathway metabolites participate in the disruption of epithelial barrier function that is characteristic of inflammatory bowel disease.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Ácidos Hidroxieicosatetraenoicos/metabolismo , Mucosa Intestinal/metabolismo , Leucotrieno D4/metabolismo , Junções Íntimas/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Cisteína , Impedância Elétrica , Epitélio/metabolismo , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Leucotrienos , Ocludina/metabolismo , Permeabilidade , Proteína Quinase C/metabolismo , Fosfolipases Tipo C/metabolismo
14.
Biochem Pharmacol ; 84(9): 1113-22, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22858365

RESUMO

Redox state unbalance and the activation of the arachidonic acid (AA) cascade, contribute to the pathogenesis of cardiovascular disease (CVD) and cancer. Inflammatory cells that infiltrate the atheroma plaque or tumor are a major source of reactive oxygen species and eicosanoids. The human antioxidant defense network is complex and interlocking and there is controversy surrounding the beneficial effects of diet-derived antioxidants in vivo. However, epidemiological studies indicate that populations that consume high levels of plant-derived foods containing phenolic compounds have low rates of CVD and cancer. The molecular mechanisms for these effects are multi-faceted. They include the regulation of transcription factors and consequently the modulation of genes (cytokines, growth factors and adhesion molecules), and growth factor-receptor interactions and cell signaling cascades, which determine the expression of genes involved in cell cycle, cell survival and apoptosis, as well as adhesiveness/invasiveness and angiogenesis. The present paper also focuses on the effects of phenolic compounds on AA cascade enzymes (cyclooxygenases and lipoxygenases) and the subsequent synthesis of eicosanoids, which are involved in CVD and cancer. A better understanding of these processes could explain the beneficial effects of polyphenols on the most prevalent diseases in Western societies. This commentary shows that antioxidants under evaluation include structural modifications of low-molecular-mass polyphenols, which could lead to a valuable strategy for modulating the generation of inflammatory mediators involved in these chronic diseases.


Assuntos
Antioxidantes/farmacologia , Ácido Araquidônico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/farmacologia , Acetilação , Animais , Antocianinas/metabolismo , Antocianinas/farmacologia , Antocianinas/uso terapêutico , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Disponibilidade Biológica , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Quimioprevenção , Suplementos Nutricionais , Flavonas/metabolismo , Flavonas/farmacologia , Flavonas/uso terapêutico , Alimentos , Histonas/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Óxido Nítrico/metabolismo , Polifenóis/metabolismo , Polifenóis/uso terapêutico , Prevalência , Transdução de Sinais , Estilbenos/metabolismo , Estilbenos/farmacologia , Estilbenos/uso terapêutico
15.
Science ; 334(6055): 487-90, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22034428

RESUMO

Images obtained by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) cameras onboard the Rosetta spacecraft reveal that asteroid 21 Lutetia has a complex geology and one of the highest asteroid densities measured so far, 3.4 ± 0.3 grams per cubic centimeter. The north pole region is covered by a thick layer of regolith, which is seen to flow in major landslides associated with albedo variation. Its geologically complex surface, ancient surface age, and high density suggest that Lutetia is most likely a primordial planetesimal. This contrasts with smaller asteroids visited by previous spacecraft, which are probably shattered bodies, fragments of larger parents, or reaccumulated rubble piles.

16.
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
17.
Int J Oral Maxillofac Surg ; 38(4): 382-4, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19217755

RESUMO

Heterotopic neuroglial tissue in the head and neck area is a rare clinical entity which can cause airway obstruction and feeding problems during the neonatal period. The case is presented of heterotopic neuroglial tissue as a congenital laterocervical and intraoral mass in a neonate.


Assuntos
Obstrução das Vias Respiratórias/congênito , Coristoma/congênito , Neoplasias de Cabeça e Pescoço/congênito , Neuroglia , Obstrução das Vias Respiratórias/patologia , Obstrução das Vias Respiratórias/cirurgia , Pré-Escolar , Coristoma/patologia , Coristoma/cirurgia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Palato/patologia , Palato/cirurgia , Resultado do Tratamento
18.
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.

19.
J Cell Physiol ; 189(2): 237-43, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11598909

RESUMO

Previously, we reported a growth-dependent change in prostaglandin production as a consequence of a marked growth-dependent alteration in arachidonic acid (AA) mobilization from phospholipids. Our present results show that fetal calf serum (FCS) and 4 beta-phorbol-12-myristate acetate (PMA) caused an enhancement of phospholipase A(2) (PLA(2)) activity in the membrane fraction of non-confluent cells allowing PLA(2) access to its substrate and the release of AA. Western blot analysis has shown that FCS and PMA increased secreted PLA(2) (sPLA(2)) expression in non-confluent 3T6 fibroblast cultures. Moreover, FCS and PMA induced dithiothreitol-sensitive and bromoenol lactone-sensitive PLA(2) activities in cytosol and membrane fraction. However, these stimuli did not modify significantly the PLA(2) activity in both fractions when 3T6 fibroblasts reached a high cell density. This could be associated with the impairment of AA mobilization in these cell culture conditions. On the other hand, we observed that FCS and PMA induced the same prostaglandin H synthase-2 induction in non-confluent and confluent culture conditions. Moreover, the prostaglandin E(2) levels reached in cell culture supernatants were independent of the degree of confluence when AA was added exogenously. These results suggest that the changes of intracellular distribution of PLA(2) activity of sPLA(2) and iPLA(2) stimulated by exogenous stimuli may be controlled by cell density conditions which constitute an important mechanism in the regulation of prostaglandin release.


Assuntos
Dinoprostona/biossíntese , Fibroblastos/enzimologia , Fosfolipases A/fisiologia , Animais , Ácido Araquidônico/metabolismo , Técnicas de Cultura de Células/métodos , Divisão Celular , Linhagem Celular , Meios de Cultura , Ciclo-Oxigenase 2 , Fibroblastos/citologia , Fosfolipases A2 do Grupo V , Fosfolipases A2 do Grupo VI , Membranas Intracelulares/enzimologia , Isoenzimas/metabolismo , Camundongos , Fosfolipases A/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
20.
Arch Biochem Biophys ; 392(2): 257-62, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11488600

RESUMO

Previous studies have shown that reactive oxygen species (ROS) enhance arachidonic acid (AA) release and the subsequent AA metabolism in macrophages. The purpose of this study was determined the implication of phospholipases A2 (PLA2s) in these events. Our results show that oxidative stress induced by exogenous adding of hydrogen peroxide or superoxide anion in macrophage RAW 264.7 and mouse peritoneal macrophage cultures caused a marked enhancement of calcium-independent PLA2 (iPLA2) activity,whereas the increment of secreted PLA2 (sPLA2) and calcium-dependent cytosolic PLA2 (cPLA2) activities were slight. This increase of iPLA2 activity by ROS was rapid and dose-dependent. ROS also induced a significant [3H] arachidonic acid (AA) release. The iPLA2 selective inhibitor, bromoenol lactone, almost completely suppressed the mobilization of [3H]AA induced by ROS whereas antisense oligonucleotide against cPLA2 did not have any appreciable effect. Thus, our data show that iPLA2 activity is involved in the mechanism by which ROS increases the availability of free AA in macrophages RAW 264.7. Moreover, the protein kinase C (PKC) inhibitor, calphostin C, and calcium chelators had no effect on the [3H]AA release induced by ROS, suggesting this is a regulatory role of iPLA2.


Assuntos
Ácido Araquidônico/metabolismo , Cálcio/metabolismo , Fosfolipases A/fisiologia , Espécies Reativas de Oxigênio , Acetona/farmacologia , Animais , Linhagem Celular , Quelantes/farmacologia , Citosol/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/farmacologia , Camundongos , Naftalenos/farmacologia , Fosfolipases A/química , Fosfolipases A/metabolismo , Fosfolipases A2 , Fatores de Tempo
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