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1.
Histol Histopathol ; 39(3): 303-318, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37341427

ABSTRACT

BACKGROUND: The impact of COVID-19 on pregnancy has been analyzed suggesting an increased risk of placental lesions that might lead to maternal and neonatal complications. However, the current published evidence is not conclusive because contradictory results. METHODS: PLAXAVID is an observational, retrospective, histopathological, single-center study that aimed to evaluate the prevalence of vascular and inflammatory lesions in placental and umbilical cord samples of one hundred women infected by SARS-CoV-2 during pregnancy. RESULTS: The histopathological analysis showed that in most of the placentas (77.8%) there were signs of maternal vascular malperfusion (MVM; primary endpoint). The most common MVM features were an accelerated villous maturation (37.4%), central villous infarcts (33.3%), and villous agglutination (46.5%). Fetal vascular malperfusion (FVM) was identified in 57.6% of samples, and the most frequent features were hyalinized avascular villi (38.4%), fetal vascular thrombi (20.2%) and umbilical cord at risk of partial obstruction (14.1%). Acute and chronic inflammatory pathology were noticed in 22.2% and 49.5% of placentas, respectively. No significant correlations were found between MVM presence and the time, duration, and severity of infection, nor with the duration of pregnancy. However, in critically ill patients, the pregnancy duration (p=0.008), newborn weight (p=0.003), and APGAR test scores (p<0.001) were significantly lower. The same trend was observed considering the presence of infection at the time of delivery and in preterm births. CONCLUSION: A very high percentage of placentas with vascular and/or inflammatory lesions was found in the analyzed cohort. Therefore, PLAXAVID study results supported that COVID-19 should be considered a risk factor during gestation and requires close monitoring of pregnancy.


Subject(s)
COVID-19 , Female , Humans , Infant, Newborn , Pregnancy , Duodenum , Placenta , Retrospective Studies , SARS-CoV-2
2.
Phys Rev Lett ; 119(21): 215506, 2017 Nov 24.
Article in English | MEDLINE | ID: mdl-29219416

ABSTRACT

The low-temperature thermal and transport properties of an unusual kind of crystal exhibiting minimal molecular positional and tilting disorder have been measured. The material, namely, low-dimensional, highly anisotropic pentachloronitrobenzene has a layered structure of rhombohedral parallel planes in which the molecules execute large-amplitude in-plane as well as concurrent out-of-plane librational motions. Our study reveals that low-temperature glassy anomalies can be found in a system with minimal disorder due to the freezing of (mostly in-plane) reorientational jumps of molecules between equivalent crystallographic positions with partial site occupation. Our findings will pave the way to a deeper understanding of the origin of the above-mentioned universal glassy properties at low temperature.

3.
Phys Rev Lett ; 118(10): 105701, 2017 Mar 10.
Article in English | MEDLINE | ID: mdl-28339247

ABSTRACT

We present a dynamic and thermodynamic study of the orientational glass former Freon 113 (1,1,2-trichloro-1,2,2-trifluoroethane, CCl_{2}F-CClF_{2}) in order to analyze its kinetic and thermodynamic fragilities. Freon 113 displays internal molecular degrees of freedom that promote a complex energy landscape. Experimental specific heat and its microscopic origin, the vibrational density of states from inelastic neutron scattering, together with the orientational dynamics obtained by means of dielectric spectroscopy have revealed the highest fragility value, both thermodynamic and kinetic, found for this orientational glass former. The excess in both Debye-reduced specific heat and density of states (boson peak) evidences the existence of glassy low-energy excitations. We demonstrate that early proposed correlations between the boson peak and the Debye specific heat value are elusive as revealed by the clear counterexample of the studied case.

4.
J Phys Condens Matter ; 29(8): 085405, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28095369

ABSTRACT

The transition taking place between two metastable phases in 2-O-adamantane, namely the [Formula: see text] cubic, rotator phase and the lower temperature P21/c, Z = 4 substitutionally disordered crystal is studied by means of muon spin rotation and relaxation techniques. Measurements carried out under zero, weak transverse and longitudinal fields reveal a temperature dependence of the relaxation parameters strikingly similar to those exhibited by structural glass[Formula: see text]liquid transitions (Bermejo et al 2004 Phys. Rev. B 70 214202; Cabrillo et al 2003 Phys. Rev. B 67 184201). The observed behaviour manifests itself as a square root singularity in the relaxation rates pointing towards some critical temperature which for amorphous systems is located some tens of degrees above that shown as the characteristic transition temperature if studied by thermodynamic means. The implications of such findings in the context of current theoretical approaches concerning the canonical liquid-glass transition are discussed.

5.
J Chem Phys ; 143(8): 084510, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26328859

ABSTRACT

The thermal conductivity, specific heat, and specific volume of the orientational glass former 1,1,2-trichloro-1,2,2-trifluoroethane (CCl2F-CClF2, F-113) have been measured under equilibrium pressure within the low-temperature range, showing thermodynamic anomalies at ca. 120, 72, and 20 K. The results are discussed together with those pertaining to the structurally related 1,1,2,2-tetrachloro-1,2-difluoroethane (CCl2F-CCl2F, F-112), which also shows anomalies at 130, 90, and 60 K. The rich phase behavior of these compounds can be accounted for by the interplay between several of their degrees of freedom. The arrest of the degrees of freedom corresponding to the internal molecular rotation, responsible for the existence of two energetically distinct isomers, and the overall molecular orientation, source of the characteristic orientational disorder of plastic phases, can explain the anomalies at higher and intermediate temperatures, respectively. The soft-potential model has been used as the framework to describe the thermal properties at low temperatures. We show that the low-temperature anomaly of the compounds corresponds to a secondary relaxation, which can be associated with the appearance of Umklapp processes, i.e., anharmonic phonon-phonon scattering, that dominate thermal transport in that temperature range.

6.
J Phys Chem B ; 119(26): 8468-74, 2015 Jul 02.
Article in English | MEDLINE | ID: mdl-26073682

ABSTRACT

The heat capacity and thermal conductivity of the monoclinic and the fully ordered orthorhombic phases of 2-adamantanone (C10H14O) have been measured for temperatures between 2 and 150 K. The heat capacities for both phases are shown to be strikingly close regardless of the site disorder present in the monoclinic crystal which arises from the occupancy of three nonequivalent sites for the oxygen atom. The heat capacity curves are also well accounted for by an evaluation carried out within the harmonic approximation in terms of the g(ω) vibrational frequency distributions measured by means of inelastic neutron scattering. Such spectral functions show however a significant excess of low frequency modes for the crystal showing statistical disorder. In contrast, large differences are found for the thermal conductivity which contrary to what could be expected, shows the substitutionally disordered crystal to exhibit better heat transport properties than the fully ordered orthorhombic phase. Such an anomalous behavior is understood from examination of the crystalline structure of the orthorhombic phase which leads to very strong scattering of heat-carrying phonons due to grain boundary effects able to yield a largely reduced value of the conductivity as well as to a plateau-like feature at intermediate temperatures which contrasts with a bell-shaped maximum shown by data pertaining the disordered crystal. The relevance of the present findings within the context of glassy dynamics of the orientational glass state is finally discussed.

7.
An Pediatr (Barc) ; 83(2): 94-103, 2015 Aug.
Article in Spanish | MEDLINE | ID: mdl-25555366

ABSTRACT

OBJECTIVE: The Childhood Asthma Control Test (c-ACT) is a validated tool for determining pediatric asthma control. However, it is not validated in the Spanish language in Spain. We evaluated the psychometric properties of the Spanish version of the Childhood Asthma Control Test (Sc-ACT) for assessing asthma control in children ages 4 to11. METHODS: This national, multicentre, prospective study was conducted in Spain with asthmatic children and their caregivers. Patients were assessed at 3 visits (Baseline, 2 Weeks, and 4 Months). Clinical variables included: symptoms, exacerbations, FEV1, asthma classification, PAQLQ and PACQLQ questionnaire scores, and asthma control as perceived by physicians, patients and caregivers. The Sc-ACT feasibility, validity, reliability, and sensitivity to change were assessed. RESULTS: A total of 394 children were included; mean (SD) time to complete the Sc-ACT was 5.3 (4.4) minutes. Sc-ACT score was correlated with asthma control as perceived by physician (-0.52), patient (-0.53), and caregiver (-0.51) and with the PAQLQ (0.56) and PACQLQ (0.55) scores. Sc-ACT was found to be significantly related to intensity and frequency of asthma symptoms. Cronbach alpha coefficient α was 0.81 and intraclass correlation coefficient was ≥0.85 for all of the items. The global effect size of Sc-ACT was 0.55. The cutoff point scores of 21 or higher indicated a good asthma control and their MCID was 4 points. CONCLUSION: The Spanish version of the c-ACT was found to be a reliable and valid questionnaire for evaluating asthma control in Spanish-speaking children ages 4 to 11 in Spain.


Subject(s)
Asthma , Surveys and Questionnaires , Asthma/diagnosis , Asthma/prevention & control , Child , Female , Humans , Language , Male , Prospective Studies , Spain
8.
Med Intensiva ; 38(1): 33-40, 2014.
Article in Spanish | MEDLINE | ID: mdl-24315132

ABSTRACT

Ultrasound has become an essential tool in assisting critically ill patients. His knowledge, use and instruction requires a statement by scientific societies involved in its development and implementation. Our aim are to determine the use of the technique in intensive care medicine, clinical situations where its application is recommended, levels of knowledge, associated responsibility and learning process also implement the ultrasound technique as a common tool in all intensive care units, similar to the rest of european countries. The SEMICYUC's Working Group Cardiac Intensive Care and CPR establishes after literature review and scientific evidence, a consensus document which sets out the requirements for accreditation in ultrasound applied to the critically ill patient and how to acquire the necessary skills. Training and learning requires a structured process within the specialty. The SEMICYUC must agree to disclose this document, build relationships with other scientific societies and give legal cover through accreditation of the training units, training courses and different levels of training.


Subject(s)
Clinical Competence , Critical Care , Health Personnel/education , Ultrasonography , Humans
9.
Med Intensiva ; 38(1): 11-20, 2014.
Article in Spanish | MEDLINE | ID: mdl-23909987

ABSTRACT

OBJECTIVES: To evaluate the effects of the early administration of statins during acute myocardial infarction (MI). DESIGN: A retrospective cohort study was carried out. SETTING: National (Spain). PATIENTS OR PARTICIPANTS: Patients included in the ARIAM registry from January 1999 to December 2008 with a diagnosis of MI. INTERVENTIONS: None. MAIN VARIABLES: We used logistic regression analysis and propensity scoring to determine whether the administration of statins during the first 24h of MI acts as a protective factor against: 1) mortality, 2) the incidence of lethal arrhythmias, or 3) cardiogenic shock. RESULTS: A total of 36 842 patients were included in the study. Statins were administered early in 50.2% of the patients. Statin administration was associated with younger patients with known previous dyslipidemia, obesity, a history of ischemic heart disease, heart failure, presence of sinus tachycardia, use of beta-blockers, angiotensin-converting enzyme inhibitors, thrombolysis and percutaneous coronary intervention. Mortality was 8.2% (13.2% without statin versus 3% with statin, P<.001). Multivariate analysis demonstrated that statin administration acted as a protective factor against mortality (adjusted OR 0.518, 95%CI 0.447 to 0.601). Continued use of statins was associated with a reduction in mortality (adjusted OR 0.597, 95%CI 0.449 to 0.798), and the start of treatment was a protective factor against mortality (adjusted OR 0.642, 95%CI 0.544 -0.757). Statin therapy also exerted a protective effect against the incidence of lethal arrhythmias and cardiogenic shock. CONCLUSIONS: These results suggest that early treatment with statins in patients with MI is associated with reduced mortality.


Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Myocardial Infarction/drug therapy , Cohort Studies , Female , Humans , Male , Retrospective Studies , Secondary Prevention
10.
Article in English | MEDLINE | ID: mdl-23886433

ABSTRACT

The incidence and concentration of pyrrolizidine alkaloids (PAs) from Echium spp. plant have been defined in 103 Spanish honey samples. Each sample was examined to determine total pollen content, the percentage of Echium spp. pollen, and simultaneous measurements of PAs and their N-oxides concentrations by the HPLC-ESI/MS method to identify the potential origin of PAs in honey. PAs were found in 94.2% of the raw honey samples analysed, in the range of 1-237 µg kg(-1) (average concentration = 48 µg kg(-1)). The PA pattern was clearly dominated by echimidine, lycopsamine and their N-oxides, representing the 97.8% of total ∑PAs, and only echimidine and echimidine-N-oxide surpassed the 87% of total ∑PA content. Others PAs, seneciphylline and heliotrine-N-oxide, appear to be reported in a lower incidence and concentration (average of 3 and 1 µg kg(-1), respectively). The Pearson Chi-squared test (p ≤ 0.01) confirms the non-correspondence between pollen plants and PA content. This study was also realised to generate a dataset in order to evaluate the potential risk of Spanish honeys containing PA plants belonging to the genera Echium.


Subject(s)
Echium/chemistry , Food Contamination/analysis , Honey/analysis , Pyrrolizidine Alkaloids/analysis , Animals , Chromatography, High Pressure Liquid , Echium/adverse effects , Honey/adverse effects , Humans , Molecular Structure , Pyrrolizidine Alkaloids/adverse effects , Pyrrolizidine Alkaloids/chemistry , Risk Assessment , Solid Phase Extraction , Spain , Spectrometry, Mass, Electrospray Ionization
11.
Environ Monit Assess ; 185(7): 6035-47, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23188070

ABSTRACT

The aim of this work is to determine the content of essential and toxic elements in 25 raw propolis samples, when considering pollution agents and geographical and botanical factors. The microwave-assisted digestion was the most reliable and accurate method for determination of inorganic elements in propolis samples. The results were obtained using certified reference materials in a good agreement with certified values. Inductively coupled plasma atomic emission spectroscopy was used for the determination of 23 macro- and microelements (Ag, Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Sb, Se, Si, Sn, and Zn). A Mercury analyzer was also utilized for the detection of the total Hg. Among the analyzed metals, Ca, K, Mg, Zn, Si, S, Fe, Al, P, and Na were found to be the most predominant. Heavy metals (As, Cd, Hg, and Pb) were determined in minimal concentration, and Pb was the highest mean contained toxic (<3.80 mg/kg), without influence on provisional tolerable weekly intake values. The method can be applied for routine analysis and quality and environmental pollution controls of toxic elements in propolis samples. The results obtained indicate no pollution of the collection areas and naturally high concentration of Al (460 ± 62.2 mg/kg).


Subject(s)
Environmental Monitoring/methods , Environmental Pollutants/analysis , Metals, Heavy/analysis , Propolis/chemistry , Trace Elements/analysis , Spain , Spectrophotometry, Atomic
12.
J Chem Phys ; 136(12): 124514, 2012 Mar 28.
Article in English | MEDLINE | ID: mdl-22462881

ABSTRACT

Trans-1,2-dichloroethene (HClC=CClH) has several structural and dynamic anomalies between its low- and high-density liquid, previously found through neutron scattering experiments. To explain the microscopic origin of the differences found in those experiments, a series of molecular dynamics simulations were performed. The analysis of molecular short-range order shows that the number of molecules in the first neighbor shell is 12 for the high-density liquid and 11 for the low-density one. It also shows that the angular position of the center of mass of the first neighbor is roughly the same although the molecular orientation is not. In both liquids the first neighbor and its reference molecule arrange mainly in two configurations, each being the most probable in one of the liquids. First neighbors in the configuration that predominates in the high-density liquid tend to locate themselves closer to the reference molecule, an evidence that they are more strongly bonded. This arrangement facilitates a better packing of the rest of molecules in the first neighbor shell so that on average an additional molecule can be included, and is proposed to be the key in the explanation of all the observed anomalies in the characteristics of both liquids.


Subject(s)
Dichloroethylenes/chemistry , Molecular Dynamics Simulation , Water/chemistry , Hydrogen Bonding , Models, Molecular , Thermodynamics
13.
Food Chem ; 132(1): 642-8, 2012 May 01.
Article in English | MEDLINE | ID: mdl-26434344

ABSTRACT

The physical and chemical parameters (melting point and saponification number), and the fraction of hydrocarbons, monoesters, acids and alcohols have been determined in 90 samples of Spanish commercial beeswax from Apis mellifera L. The adulteration with paraffins of different melting point, cow tallow, stearic acid, and carnauba wax were determined by HTGC-FID/MS detection, and the research was focussed mainly on paraffins and microcrystallines waxes. In general, the added adulterant can be identified by the presence of non-naturally beeswax components, and by the differences of values of selected components between pure and adulterated beeswax. The detection limits were determined using pure and adulterated beeswax with different amounts of added waxes (5%, 10%, 20% and 30%). Percentages higher than 1-5% of each adulterant can be detected in the mixtures. Paraffin waxes were confirmed in 33 of the 90 samples analysed at concentrations between 5% and 30%.


Subject(s)
Chromatography, Gas/methods , Stearic Acids/chemistry , Waxes/chemistry , Waxes/chemical synthesis , Animals , Hydrocarbons/analysis
14.
Langmuir ; 27(6): 2219-28, 2011 Mar 15.
Article in English | MEDLINE | ID: mdl-21306171

ABSTRACT

The production of high-quality colloidal crystals demands precise quantitative characterization of their nanostructures. While small-angle radiation scattering is the technique of choice, a procedure for a comprehensive quantitative modeling of the data is still pending. A novel theory based on the pertinent radial pair distribution which takes into account orientational, positional, stacking disorder and grain effects is developed here. We also show how the scattering length density of the particles can be estimated from the positions of minima in the form factor. The obtained results can be cast as sums of analytical functions over the distribution function and, as such, are suitable for easy (automatic) parallelization. On the experimental side, we report on a strong extinction effect coming from grazing incidence specular reflection that we have been able to model analytically.

17.
Phys Rev Lett ; 103(7): 075701, 2009 Aug 14.
Article in English | MEDLINE | ID: mdl-19792661

ABSTRACT

The dynamics of simple molecular systems showing glassy properties has been explored by dielectric spectroscopy and nuclear quadrupole resonance (NQR) on the halogenomethanes CBr2Cl2 and CBrCl3 in their low-temperature monoclinic phases. The dielectric spectra display features which correspond to alpha- and beta-relaxation processes, commonly observed in canonical glass formers. NQR experiments, also performed in the ergodic monoclinic phase of CCl4, enable the determination of the microscopic mechanism underlying the beta dynamics in these simple model glasses: Molecules that are nonequivalent with respect to their molecular environment perform reorientational jumps at different time scales. Thus our findings reveal another mechanism that can give rise to typical beta-relaxation behavior, raising some doubt about the existence of a universal explanation of this phenomenon.

18.
Phys Rev Lett ; 100(24): 245902, 2008 Jun 20.
Article in English | MEDLINE | ID: mdl-18643601

ABSTRACT

The stochastic dynamics of binary liquids with formula AxB1-x, x=0-0.4 is investigated by neutron spin-echo spectroscopy. These compositions comprise samples of varying chemical connectivity, ranging from twofold-coordinated liquid Se to higher average coordinated As2S3. The parameters giving the temperature dependence of the relaxation patterns show a quasilinear dependence on the average coordination number. The results thus extend the validity of the rigidity concept into the normal liquid state and emphasize the role played by the fine details of atomic bonding on the dynamics at 10 ps-1 ns scales.

19.
Actas urol. esp ; 32(2): 230-239, feb. 2008. ilus, tab
Article in Es | IBECS | ID: ibc-62846

ABSTRACT

Introducción: La Hiperplasia Benigna de Próstata (HBP) es una enfermedad crónica que afecta la calidad de vida relacionada con la salud (CVRS). En España no hay cuestionarios específicos para evaluar la CVRS en esta enfermedad. El objetivo del presente estudio fue validar la versión española del cuestionario Benign Prostatic Hyperplasia ImpactIndex (BII). Material y métodos: Participaron hombres mayores de 49 años diagnosticados de HBP evaluados en tres visitas. Se analizaron las propiedades psicométricas del cuestionario en términos de validez, fiabilidad y sensibilidad al cambio. Resultados: Se evaluaron 1.719 hombres con edad media (DE) de 68,36 años (8,07) clasificados según gravedad de la HBP. La validez longitudinal y la validez de constructo (r>0,6) del cuestionario BII fueron moderadas-altas. La consistencia interna (α=0,91), la fiabilidad test-retest (CCI=0,8) y la sensibilidad al cambio (tamaño efecto=0,6) fueron buenas. La CVRS mejoró significativamente durante el seguimiento (p<0,01).Discusión: Hasta ahora no existían cuestionarios específicos de calidad de vida para población española con HBP. La versión española del cuestionario BII cumple las propiedades psicométricas necesarias para evaluar la CVRS en la HBP; confirmando además, el significativo impacto de la enfermedad en la calidad de vida de estos pacientes (AU)


Introduction: Benign Prostatic Hyperplasia is a chronic disease that affects Health related quality of life (HRQL). In Spain there are no specific questionnaires to assess HRQL in patients suffering from BPH. The objective of this study was to validate the Spanish version of the Benign Prostatic Hyperplasia Impact Index (BII) questionnaire. Material and methods: Study participants were men over 49 with confirmed BPH diagnosis and evaluated in three visits. Psychometric properties of the questionnaire were analyzed in terms of validity, reliability and sensitivity to change. Results: A total of 1,719 men with mean (SD) age 68.36 were evaluated and classified according to the BPH severity. Both longitudinal and construct validity (r>0.6) of the BII questionnaire were moderate-high. Internal consistency (α=0.91), test-retest reliability (CCI=0.8) and sensitivity to change (effect size=0.6) showed good results. The HRQL improved significantly during the monitoring period (p<0.01).Discussion: There were no available specific HRQL questionnaires for Spanish population with BPH until now. The Spanish version of the BII questionnaire fulfils with the psychometric properties that are necessary to evaluate HRQL in patients with BPH; furthermore, it has been confirm the considerable impact of this disease in the quality of life of this patients (AU)


Subject(s)
Humans , Male , Middle Aged , Aged , Prostatic Hyperplasia/psychology , Quality of Life , Surveys and Questionnaires , Severity of Illness Index , Reproducibility of Results , Translating , Psychometrics , Spain
20.
Phys Rev Lett ; 98(21): 215503, 2007 May 25.
Article in English | MEDLINE | ID: mdl-17677785

ABSTRACT

The effects of confining molecular hydrogen within carbon nanohorns are studied via high-resolution quasielastic and inelastic neutron spectroscopies. Both sets of data are remarkably different from those obtained in bulk samples in the liquid and crystalline states. At temperatures where bulk hydrogen is liquid, the spectra of the confined sample show an elastic component indicating a significant proportion of immobile molecules as well as distinctly narrower quasielastic line widths and a strong distortion of the line shape of the para-->ortho rotational transition. The results show that hydrogen interacts far more strongly with such carbonous structures than it does to carbon nanotubes, suggesting that nanohorns and related nanostructures may offer significantly better prospects as lightweight media for hydrogen storage applications.

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