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1.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298431

RESUMO

This paper presents a polarization calibration method applied to a microwave polarimeter demonstrator based on a near-infrared (NIR) frequency up-conversion stage that allows both optical correlation and signal detection at a wavelength of 1550 nm. The instrument was designed to measure the polarization of cosmic microwave background (CMB) radiation from the sky, obtaining the Stokes parameters of the incoming signal simultaneously, in a frequency range from 10 to 20 GHz. A linearly polarized input signal with a variable polarization angle is used as excitation in the polarimeter calibration setup mounted in the laboratory. The polarimeter systematic errors can be corrected with the proposed calibration procedure, achieving high levels of polarization efficiency (low polarization percentage errors) and low polarization angle errors. The calibration method is based on the fitting of polarization errors by means of sinusoidal functions composed of additive or multiplicative terms. The accuracy of the fitting increases with the number of terms in such a way that the typical error levels required in low-frequency CMB experiments can be achieved with only a few terms in the fitting functions. On the other hand, assuming that the calibration signal is known with the required accuracy, additional terms can be calculated to reach the error levels needed in ultrasensitive B-mode polarization CMB experiments.

2.
Phys Rev Lett ; 128(9): 091302, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302802

RESUMO

We search for the signature of parity-violating physics in the cosmic microwave background, called cosmic birefringence, using the Planck data release 4. We initially find a birefringence angle of ß=0.30°±0.11° (68% C.L.) for nearly full-sky data. The values of ß decrease as we enlarge the Galactic mask, which can be interpreted as the effect of polarized foreground emission. Two independent ways to model this effect are used to mitigate the systematic impact on ß for different sky fractions. We choose not to assign cosmological significance to the measured value of ß until we improve our knowledge of the foreground polarization.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32505121

RESUMO

The WHO recommends exclusive breastfeeding of infants for the first sixth months of life and advises that it shall continue for up to two years of age or beyond in combination with complementary foods. However, the image of a woman breastfeeding a toddler or a preschooler is unusual in western societies. Exploring the nutritional properties of milk during prolonged lactation can help normalizing prolonged breastfeeding. Human milk fatty acid composition was determined in sixteen lactating mothers practicing prolonged lactation (≥12 months) and sixteen women on their first twelve months of lactation. Breast milk after one year is richer in saturated fatty acids, particularly lauric and myristic, showing a tendency towards lower levels of oleic acid, and higher of arachidonic, α-linolenic and docosahexaenoic acids, in comparison to early milk (< 1 year). The age and body condition of the mother, parity, sex of the baby, and diet influence also the fattyacidome of milk.


Assuntos
Aleitamento Materno , Ácidos Graxos/metabolismo , Lactação , Leite Humano/metabolismo , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Espanha
6.
Arch Soc Esp Oftalmol (Engl Ed) ; 94(10): 500-503, 2019 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31326157

RESUMO

In severe cases of abducens or sixth cranial nerve palsy, transpositions of the superior rectus and inferior rectus into the paralytic lateral rectus have been demonstrated to be useful. Numerous techniques have been described over time to carry out these transpositions, such as the Hummelsheim, O'Connor, Jensen, Foster, or Nishida technique. The first 4 techniques mentioned above have an increased risk of anterior segment ischaemia. The case is presented of a long-standing bilateral sixth cranial nerve palsy secondary to a severe cranial injury. Given the risk of ischaemia of the anterior segment, the Nishida technique was chosen in order to reduce the risk of suffering from this complication. This is combined with botulinum toxin in both middle rectus to try to resolve the muscle contracture associated with the long evolution of the case, obtaining good results at 6, and 12 months after the surgical procedure.


Assuntos
Doenças do Nervo Abducente/terapia , Toxinas Botulínicas/uso terapêutico , Procedimentos Cirúrgicos Oftalmológicos/métodos , Doenças do Nervo Abducente/patologia , Adulto , Terapia Combinada , Humanos , Masculino , Fatores de Tempo
7.
Artigo em Inglês | MEDLINE | ID: mdl-30103921

RESUMO

Based on the premise that the fatty acid composition of human milk can be substantially altered by diet, the current study investigated the fatty acid profile (fattyacidome) of breast milk in Galicia, a small region located in the north-west of Spain and characterized by the Southern European Atlantic Diet (SEAD). A cross-country comparison was also performed to assess worldwide variety and diet impact, reviewing the profiles reported various European, North and South American, Asian and African countries and Australia. Galician human milk appeared similar to the rest of Europe, with some particular features related to the SEAD (dairy, pork, beef and sunflower and olive oils), such as relatively high levels of linoleic acid and lower α-linolenic acid. The results also showed the existence of woman-specific profiles and significant changes over lactation in some fatty acids. Worldwide, the fatty acid profiles were similar, with the clear exception of Asiatic breast milk. The impact of fatty acids on infant health warrants further investigation.


Assuntos
Ácidos Graxos/análise , Comportamento Alimentar/classificação , Leite Humano/química , Adulto , Feminino , Humanos , Ácido Linoleico/análise , Fatores Sexuais , Espanha , Ácido alfa-Linolênico/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-28100121

RESUMO

Milk from 40 Holstein dairy cows was collected from two different farms in Galicia (Spain). The differences in the fatty acid composition of two groups of cows, 20 pregnant and 20 non-pregnant, was studied to determine whether pregnancy status is a determinant factor that can alter the fatty acid profile of milk. Gas-chromatography (GC) coupled to flame ionisation detection (FID) was used for the determination of the fatty acids. Differences in the milk fatty acids between pregnant and non-pregnant cows were pronounced showing statistically significant differences for some fatty acids and the total saturated and monounsaturated fatty acids. Milk from non-pregnant cows was lower in saturated fatty acids and higher in monounsaturated fatty acids (unlike milk from pregnant cows). The effects of the consumption of bovine milk, particularly milk fat, on human health have been studied in depth and sometimes are associated with negative effects, but milk has also several beneficial characteristics linked to some fatty acids.


Assuntos
Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos/análise , Lactação/fisiologia , Leite/química , Valor Nutritivo , Animais , Bovinos , Dieta , Feminino , Ionização de Chama , Humanos , Gravidez , Espanha
9.
Mar Pollut Bull ; 114(2): 715-723, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27806895

RESUMO

Imposex is decreasing worldwide after the total ban on tributyltin (TBT) from antifouling paints. In order to assess improvement in the NE Atlantic, the OSPAR Convention designed an Ecological Quality Objective (EcoQO) based on the VDSI (vas deferens sequence index, an agreed measure of imposex) in the rock snail Nucella lapillus; wherever this is not available, the mud snail Nassarius reticulatus was proposed as a proxy. We determined VDSI in Galician populations of rock (n≥34) and mud (n≥18) snails at regular intervals from pre-ban times until 2009 and 2011, respectively. While imposex in the former started decreasing in 2006 and by 2009 the EcoQO had been met in the area, VDSI in the latter was not significantly reduced until 2011 and values contradict such an achievement. This suggests that the OSPAR imposex bi-species scheme may not be of direct application in the current post-ban scenario.


Assuntos
Transtornos do Desenvolvimento Sexual/induzido quimicamente , Monitoramento Ambiental/métodos , Caramujos/efeitos dos fármacos , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Animais , Feminino , Masculino , Pênis/efeitos dos fármacos , Pênis/crescimento & desenvolvimento , Caramujos/crescimento & desenvolvimento , Espanha , Especificidade da Espécie , Compostos de Trialquitina/toxicidade , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade
10.
PLoS One ; 10(4): e0122604, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25849355

RESUMO

The activation of G-protein coupled receptors by agonist compounds results in diverse biological responses in cells, such as the endocytosis process consisting in the translocation of receptors from the plasma membrane to the cytoplasm within internalizing vesicles or endosomes. In order to functionally evaluate endocytosis events resulted from pharmacological responses, we have developed an image analysis method -the Q-Endosomes algorithm- that specifically discriminates the fluorescent signal originated at endosomes from that one observed at the plasma membrane in images obtained from living cells by fluorescence microscopy. Mu opioid (MOP) receptor tagged at the carboxy-terminus with yellow fluorescent protein (YFP) and permanently expressed in HEK293 cells was used as experimental model to validate this methodology. Time-course experiments performed with several agonists resulted in different sigmoid curves depending on the drug used to initiate MOP receptor endocytosis. Thus, endocytosis resulting from the simultaneous activation of co-expressed MOP and serotonin 5-HT2C receptors by morphine plus serotonin was significantly different, in kinetics as well as in maximal response parameters, from the one caused by DAMGO, sufentanyl or methadone. Therefore, this analytical tool permits the pharmacological characterization of receptor endocytosis in living cells with functional and temporal resolution.


Assuntos
Endocitose/efeitos dos fármacos , Receptor 5-HT2C de Serotonina/metabolismo , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Células HEK293 , Meia-Vida , Células HeLa , Humanos , Cinética , Microscopia de Fluorescência , Transporte Proteico , Serotonina/farmacologia , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Vesículas Transportadoras/metabolismo
11.
Phys Rev Lett ; 114(10): 101301, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25815919

RESUMO

We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.

12.
Sci Total Environ ; 502: 167-71, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25260162

RESUMO

Environmental quality in coastal Europe has improved since the complete 2003 ban on the use of tributyltin (TBT) in antifouling paints. However, there is evidence that TBT is entering the water column, presumably from illegal practices. We determined the concentration of butyltins (BTs: TBT and derivatives) in populations of two gastropods, the rock snail Nucella lapillus (n=17) and the mud snail Nassarius reticulatus (n=18) at regular intervals from pre-ban times until 2009 and 2011, respectively, in NW Spain. Although a substantial decline in TBT occurred shortly after the ban, no significant changes were observed in either species over the last 3-year period of study. In addition, the proportion of TBT relative to the sum of BTs (a marker of recent pollution) in the most recent rock snail samples unexpectedly increased; this proportion therefore showed a generally decreasing but oscillatory trend over time. The results are consistent with the theoretical expectation of BT desorption from sediments; however, this natural phenomenon is now interpreted as a recurrent episode rather than a unique, transient event. Evidence of this subtle input improves our understanding of TBT persistence in the environment in Europe and worldwide.


Assuntos
Monitoramento Ambiental , Gastrópodes/metabolismo , Compostos de Trialquitina/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Pintura , Água do Mar/química , Espanha , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade
13.
Mar Pollut Bull ; 60(6): 931-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20430408

RESUMO

Worldwide measures to restrict tributyltin (TBT) in antifouling paints have been legislated for decades, and were upgraded to a total ban on September 2008. With a view to test the response of coastal biota to changing pollution, since 1996 we have determined the concentration of TBT and derivatives di- and mono-butyltin (DBT and MBT) in NW Spain populations of two gastropods of contrasting biology, the rock-snail Nucella lapillus (n=18) and the mud-snail Nassarius reticulatus (n=24). TBT pollution in the study area has decreased consistently and considerably over time. In addition, the baseline butyltin (BT) bioaccumulation patterns showed a marked but transient distortion. These field observations are consistent with BT desorption from sediments, a natural phenomenon that is now to be expected in developing countries recently subject to the global TBT ban.


Assuntos
Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/farmacocinética , Gastrópodes/metabolismo , Compostos Orgânicos de Estanho/farmacocinética , Compostos de Trialquitina/farmacocinética , Animais , Coleta de Dados , Poluentes Ambientais/análise , Estudos Longitudinais , Compostos Orgânicos de Estanho/análise , Espanha , Especificidade da Espécie , Compostos de Trialquitina/análise
14.
Chemosphere ; 76(3): 424-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19380158

RESUMO

The gastropod Nassarius reticulatus has been used as a tributyltin (TBT) biomonitor over the last two decades, and it is now endorsed by Atlantic Europe environmental agencies. However, there is one important question debated by the earliest studies still unresolved, namely whether butyltin accumulation in tissues is sex-dependent or not. Thus, a field survey was conducted along the Cantabrian coast: samples were subject to both customary imposex and modern chemical analyses. No significant bioaccumulation differences between sexes were found for any of the three butyltin species examined (i.e. TBT plus derivatives di- and mono-butyltin). In addition, both lower-than-expected absolute butyltins and minor relative TBT proportions in tissues conform with decreasing pollution in nearby areas. Imposex, though, is generally still considerable due to a lesser responsiveness of population indexes. Finally, one sample showed no sign of imposex but quantifiable butyltins; these are good news indicating that TBT is getting back down to levels around the induction threshold of this specific biological effect.


Assuntos
Gastrópodes/efeitos dos fármacos , Compostos de Trialquitina/química , Animais , Monitoramento Ambiental , Gastrópodes/fisiologia , Água do Mar , Fatores Sexuais , Espanha , Compostos de Trialquitina/análise
15.
Chemosphere ; 73(8): 1253-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18760444

RESUMO

Two monitoring surveys were repeated in Galicia (NW Spain): one in 2003 concerned the rocky shore gastropod Nucella lapillus (19 populations, the reference campaign in 1996), the other dealt in 2005 with the infaunal snail Nassarius reticulatus (25 sites, the previous one in 2000). Samples were subject to a standard protocol to determine the concentrations of butyltins (BTs) in tissues. Results show that pollution in most populations has considerably decreased over the last decade: for N. lapillus the mean descent ranged from 37% (for tributyltin -TBT-) to 66% (for monobutyltin -MBT-), and TBT concentrations were on average halved in N. reticulatus. However, derivatives generally increased in this latter species, to the extent that dibutyltin -DBT- in several 2005 samples exceeded the aggregate of all three BTs in 2000. As a consequence, a major change in the bioaccumulation patterns becomes evident, particularly when computing the butyltin degradation index [BDI: (DBT+MBT)/TBT]. This shift is most marked at sites where pollution has always been lowest, and it shows significant negative correlation between both gastropods. Since sources other than antifouling paints are not important in the area, it is proposed that observations are due to BT desorption from sediments through some interplay involving the different characteristics of the chemicals and the contrasting biology of the animals.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Gastrópodes/metabolismo , Sedimentos Geológicos/química , Compostos de Trialquitina/química , Compostos de Trialquitina/metabolismo , Absorção , Animais , Feminino
16.
An Med Interna ; 21(10): 483-7, 2004 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-15511198

RESUMO

BACKGROUND: To try established antimicrobial susceptibility patterns and frequency of both nosocomial and community-acquired bloodstream infections and and to try identified the prognostic factors that can be modified. MATERIAL AND METHODS: A prospective study of 310 bloodstream infections with clinical significance detected in a non teaching hospital over period from October 2000-2001. A blood culture were identified by Bact-Alert system and the confirmation was performed by MicroScan system; an antimicrobial susceptibility test was performed by reference microdilution methods as described by NCCLS. We studied sentinel antimicrobial/organism combinations with potential clinical importance. Data were computerized using SPSS. Qualitative variables were compared using the X2 test or the Fisher exact test, and quantitative variables with t Student or ANOVA. RESULTS: Gram positive and Candida were frequently recovered in nosocomial bloodstreams. The proportion of oxacillin-resistant S. aureus isolates was 24% and the penicillin resistant pneumococci was 14%. Vancomycin was universal active against gram positive. Gram negatives were often recovered in community bloodstream. The proportion of EBSL E. coli isolates was < 2% and the proportion of multiresistance Pseudomonas aeruginosa was higher among UCI isolates. An independent risk factors for death identified after multivariate analysis was the inappropriate antimicrobial therapy OR 2.6. CONCLUSIONS: Ongoing surveillance of microbial pathogens and their resistance profiles is essential on local scale and permit the selection of appropriate antibiotic therapy which would be reduce the mortality.


Assuntos
Resistência Microbiana a Medicamentos , Sepse/tratamento farmacológico , Hospitalização , Humanos , Sepse/mortalidade , Espanha
17.
An. med. interna (Madr., 1983) ; 21(10): 483-487, oct. 2004.
Artigo em Es | IBECS | ID: ibc-36269

RESUMO

Objetivo: Conocer los patógenos prevalentes y los patrones de resistencia de las bacteriemias nosocomiales y adquiridas. Material y métodos: Estudio prospectivo de 310 bacteriemias "significativas" detectadas en un hospital no universitario en el periodo octubre 2000-2001. Los hemocultivos se detectaron por el sistema Bact-Alert y la identificación definitiva se efectuó con el sistema MicroScan, con estudio de sensibilidad por el método de microdilución de referencia (NCLSS). Se estudiaron combinaciones "centinela" con relevancia clínica. El análisis estadístico utilizó el programa SPSS. El análisis univariante utilizó para variables cuantitativas t Student y para cualitativa test X2 o t Fisher. Resultados: Los gram positivos y las levaduras predominaron en las nosocomiales. Hubo un 24 por ciento de MARSA y un 14 por ciento de neumococos penicilina resistentes. La vancomicina mantuvo una sensibilidad universal. Los gram negativos dominaron en las comunitarias, E. coli (40 por ciento) con una prevalencia de EBSL < 2 por ciento. Destacamos las tasas de multiresistencia para P. aeruginosa en las unidades de agudos. Un análisis de regresión logística reveló al tratamiento empírico inadecuado como un factor independiente de mortalidad (OR 2,6). Conclusiones: La necesidad de un sistema de vigilancia que permita conocer la prevalencia y resistencia de los microorganimos locales y establecer terapéuticas empíricas adecuadas que permitan reducir la mortalidad (AU)


Assuntos
Humanos , Resistência Microbiana a Medicamentos , Hospitalização , Espanha , Sepse
20.
Mar Environ Res ; 54(3-5): 657-60, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12408631

RESUMO

TBT induces imposex and sterilisation in female Nucella lapillus. Interestingly, there are populations where individuals (both males and imposexed females) may suffer from a genetic aberration [Dumpton Syndrome (DS)] which results in the development of no penis (i.e. aphally). This anomaly confers a so far unexplained protection against TBT. Six populations with contrasting DS frequency were sampled; the imposex stage in females and the mean calibre of every vas deferens (VDC) were assessed. While the sex ratio in the 600 specimens examined was close to 1, aphally was more frequent in females than in males (31 and 7%, respectively). VDC was significantly higher in normal than in aphallic (DS) specimens, independently of sex and/or site. It is concluded that the vas deferens imposed by TBT onto DS females is less prone to develop thick enough so as to interfere with normal egg laying.


Assuntos
Transtornos do Desenvolvimento Sexual/etiologia , Transtornos do Desenvolvimento Sexual/veterinária , Predisposição Genética para Doença , Infertilidade/veterinária , Pênis/anormalidades , Caramujos , Compostos de Trialquitina/efeitos adversos , Ducto Deferente/anormalidades , Poluentes Químicos da Água/efeitos adversos , Animais , Feminino , Infertilidade/etiologia , Masculino , Razão de Masculinidade , Caramujos/genética , Síndrome
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