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1.
Cureus ; 15(10): e47900, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38034262

RESUMEN

Ectopic pregnancies, characterized by the implantation of a fertilized ovum outside the uterine cavity, typically occur in the fallopian tubes. However, rare cases have been reported where implantation occurs in atypical locations. Round ligament pregnancy, a rare form of ectopic pregnancy, poses significant risks and can lead to life-threatening complications. This case report describes the presentation and management of a 31-year-old gravida four, para two (G4P2012) female who presented with acute left lower quadrant and pelvic pain. The patient's medical history included a prior bilateral salpingectomy. Physical examination revealed severe left lower quadrant tenderness with guarding. A positive urine pregnancy test and elevated serum quantitative beta-human chorionic gonadotrophin level of 1,735 mIU/mL (normal range: <5 mIU/mL) confirmed pregnancy. Transvaginal ultrasound revealed an empty intrauterine cavity with no gestational sac or fetal pole. A 2 cm cystic structure was identified attached to the left ovary. Ectopic pregnancy was diagnosed, methotrexate was administered, and the patient was discharged with a scheduled outpatient follow-up. However, she returned to the emergency room within 48 hours reporting persistent pelvic pain. At this moment, it was decided that emergent surgical intervention was required. The surgical exploration confirmed the presence of a ruptured ectopic pregnancy in the round ligament, requiring excision and hemostasis. This case report highlights the importance of considering abnormal localization of ectopic pregnancy as a differential diagnosis in women presenting with pelvic pain, even after bilateral salpingectomies. It emphasizes the challenges in diagnosis and management when ectopic pregnancy occurs in atypical sites and highlights the necessity for vigilant follow-up and prompt surgical intervention when medical management fails.

2.
Med Eng Phys ; 110: 103919, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36564142

RESUMEN

This paper is aimed at identifying by means of micro-CT the microstructural differences between normal and degenerative mitral marginal chordae tendineae. The control group is composed of 21 normal chords excised from 14 normal mitral valves from heart transplant recipients. The experimental group comprises 22 degenerative fibroelastic chords obtained at surgery from 11 pathological valves after mitral repair or replacement. In the control group the superficial endothelial cells and spongiosa layer remained intact, covering the wavy core collagen. In contrast, in the experimental group the collagen fibers were arranged as straightened thick bundles in a parallel configuration. 100 cross-sections were examined by micro-CT from each chord. Each image was randomized through the K-means machine learning algorithm and then, the global and local Shannon entropies were obtained. The optimum number of clusters, K, was estimated to maximize the differences between normal and degenerative chords in global and local Shannon entropy; the p-value after a nested ANOVA test was chosen as the parameter to be minimized. Optimum results were obtained with global Shannon entropy and 2≤K≤7, providing p < 0.01; for K=3, p = 2.86·10-3. These findings open the door to novel perioperative diagnostic methods in order to avoid or reduce postoperative mitral valve regurgitation recurrences.


Asunto(s)
Células Endoteliales , Insuficiencia de la Válvula Mitral , Humanos , Cuerdas Tendinosas/patología , Colágeno , Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/cirugía , Microtomografía por Rayos X
3.
Acta Neuropathol ; 144(4): 603-614, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35947184

RESUMEN

Neuropathologic criteria for progressive supranuclear palsy (PSP) proposed by a National Institute of Neurological Disorders and Stroke (NINDS) working group were published in 1994 and based on the presence of neurofibrillary tangles in basal ganglia and brainstem. These criteria did not stipulate detection methods or incorporate glial tau pathology. In this study, a group of 14 expert neuropathologists scored digital slides from 10 brain regions stained with hematoxylin and eosin (H&E) and phosphorylated tau (AT8) immunohistochemistry. The cases included 15 typical and atypical PSP cases and 10 other tauopathies. Blinded to clinical and neuropathological information, raters provided a categorical diagnosis (PSP or not-PSP) based upon provisional criteria that required neurofibrillary tangles or pretangles in two of three regions (substantia nigra, subthalamic nucleus, globus pallidus) and tufted astrocytes in one of two regions (peri-Rolandic cortices, putamen). The criteria showed high sensitivity (0.97) and specificity (0.91), as well as almost perfect inter-rater reliability for diagnosing PSP and differentiating it from other tauopathies (Fleiss kappa 0.826). Most cases (17/25) had 100% agreement across all 14 raters. The Rainwater Charitable Foundation criteria for the neuropathologic diagnosis of PSP feature a simplified diagnostic algorithm based on phosphorylated tau immunohistochemistry and incorporate tufted astrocytes as an essential diagnostic feature.


Asunto(s)
Parálisis Supranuclear Progresiva , Tauopatías , Humanos , Ovillos Neurofibrilares/patología , Neuropatología , Reproducibilidad de los Resultados , Parálisis Supranuclear Progresiva/diagnóstico , Parálisis Supranuclear Progresiva/patología , Tauopatías/diagnóstico , Tauopatías/patología , Proteínas tau
4.
Sci Total Environ ; 819: 153129, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35041963

RESUMEN

CO2 and CH4 outliers may have a noticeable impact on the trend of both gases. Nine years of measurements since 2010 recorded at a rural site in northern Spain were used to investigate these outliers. Their influence on the trend was presented and two limits were established. No more than 23.5% of outliers should be excluded from the measurement series in order to obtain representative trends, which were 2.349 ± 0.012 ppm year-1 for CO2 and 0.00879 ± 0.00004 ppm year-1 for CH4. Two types of outliers were distinguished. Those above the trend line and the rest below the trend line. Outliers were described by skewed distributions where the Weibull distribution figures prominently in most cases. A qualitative procedure was presented to exclude the worst fits, although five statistics were considered to select the best fit. In this case, the modified Nash-Sutcliffe efficiency is prominent. Finally, three symmetrical distributions were added to fit the observations when outliers are excluded, with the Gaussian and beta distributions providing the best fits. As a result, certain skewed functions, such as the lognormal distribution, whose use is frequent for air pollutants, could be questioned in certain applications.


Asunto(s)
Contaminantes Atmosféricos , Dióxido de Carbono , Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , Humanos , Metano/análisis , Población Rural , España
5.
Polymers (Basel) ; 13(23)2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34883653

RESUMEN

In oil-immersed power transformers, the insulation system is constituted of a dielectric oil-solid combination. The insulation oil generally used is mineral oil; however, this fluid has started to be substituted by natural and synthetic esters due to their higher biodegradability and flash point. The introduction of a new fluid in the insulation system of power transformers requires kinetic models that can estimate the degradation rate of insulation solids. The aim of this work was to go further in quantifying through different kinetic models the deterioration suffered by a commercial cellulose board (PSP 3055), which is one of the solid materials used in the insulation system of oil-filled transformers. The aging study was extended to cellulose board specimens immersed in two different oils (mineral and synthetic ester). It was obtained that there is a lower degradation when synthetic ester is used in the insulation system. Additionally, it can be concluded that the use of mechanical properties to quantify the degradation of the cellulose board through kinetic models provides information about the different behavior shown by PSP 3055 when different fiber direction angles are considered.

7.
Artículo en Inglés | MEDLINE | ID: mdl-34444147

RESUMEN

Meteorological variables have a noticeable impact on pollutant concentrations. Among these variables, wind speed is typically measured, although research into how pollutants respond to it can be improved. This study considers nine years of hourly CO2 and CH4 measurements at a rural site, where wind speed values were calculated by the METEX model. Nine wind speed intervals are proposed where concentrations, distribution functions, and daily as well as annual cycles are calculated. Contrasts between local and transported concentrations are around 5 and 0.03 ppm for CO2 and CH4, respectively. Seven skewed distributions are applied, and five efficiency criteria are considered to test the goodness of fit, with the modified Nash-Sutcliffe efficiency proving to be the most sensitive statistic. The Gumbel distribution is seen to be the most suitable for CO2, whereas the Weibull distribution is chosen for CH4, with the exponential function being the worst. Finally, daily and annual cycles are analysed, where a gradual decrease in amplitude is observed, particularly for the daily cycle. Parametric and nonparametric procedures are used to fit both cycles. The latter gave the best fits, with the agreement being higher for the daily cycle, where evolution is smoother than for the annual cycle.


Asunto(s)
Contaminantes Atmosféricos , Viento , Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , Monitoreo del Ambiente , Humanos , Población Rural
9.
Sci Total Environ ; 774: 145665, 2021 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-33607428

RESUMEN

Pollution control is based on an exhaustive knowledge of concentration distributions. This study analyses a detailed database of NO2, O3, PM10 and PM2.5 in England and Wales over the period 2007-2011. Daily and annual means were considered in a 1-km spatial resolution. Histograms revealed a shape like a sawtooth. The interval was wide for NO2 and O3, although with a gap, whilst the particulate matter range was narrow. Spring provided the peak for the O3 annual cycle, whereas minima for the other pollutants were reached in summer. A trend for the annual medians of particulate matter was observed, with a minimum in the period analysed. However, the pattern was uniform for NO2 and O3. Cities appeared as NO2 hot spots and O3 cold spots. Wales stood out as an NO2 clean country, although with high O3 levels. Sources or sinks of particulate matter were not observed, suggesting that more detailed analysis is required. Two NO2 pollution axes were sometimes seen, one in the south from London to Bristol, and the second in the north, from Liverpool to Kingston Upon Hull. No annual spatial pattern was seen for the remaining pollutants beyond the contrast between cities and country sites for O3. Consequently, spatial analysis allows the real impact of pollutant sources be known, although it must be performed with a detailed temporal resolution in order to investigate the extension, quantity, and length of the concentrations calculated.

11.
Artículo en Inglés | MEDLINE | ID: mdl-33187359

RESUMEN

Although emissions have a direct impact on air pollution, meteorological processes may influence inmission concentration, with the only way to control air pollution being through the rates emitted. This paper presents the close relationship between air pollution and meteorology following the scales of atmospheric motion. In macroscale, this review focuses on the synoptic pattern, since certain weather types are related to pollution episodes, with the determination of these weather types being the key point of these studies. The contrasting contribution of cold fronts is also presented, whilst mathematical models are seen to increase the analysis possibilities of pollution transport. In mesoscale, land-sea and mountain-valley breezes may reinforce certain pollution episodes, and recirculation processes are sometimes favoured by orographic features. The urban heat island is also considered, since the formation of mesovortices determines the entry of pollutants into the city. At the microscale, the influence of the boundary layer height and its evolution are evaluated; in particular, the contribution of the low-level jet to pollutant transport and dispersion. Local meteorological variables have a major influence on calculations with the Gaussian plume model, whilst some eddies are features exclusive to urban environments. Finally, the impact of air pollution on meteorology is briefly commented on.


Asunto(s)
Contaminación del Aire , Monitoreo del Ambiente , Meteorología , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Calor , Meteorología/normas , Material Particulado/análisis
12.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20189373

RESUMEN

An observational study based on official data (CONACYT and Ministry of Health) was carried out in which the effective reproduction index R(e) and the reproduction index R0 are compared with the mobility presented by Google. Additionally, an overview of the development of the pandemic in Queretaro, Mexico. Highlights key events; such as the main government interventions and social factors that could affect societys behavior. A positive relationship is observed between Re, R0, and the levels of mobility presented by Google. This indicates that an increase in mobility is associated with the transmission of SARSCoV-2. In February, a significant decrease in mobility is observed, which lasts until approximately May 1st. This period corresponds to an R0 and R(e) between 1.17 and 1.87. After May 1st, there is a sustained increase in mobility levels. And, as of May 16, the effective reproduction index R (e) and the reproduction index R0 begin to increase. This is expected as it reflects the delay between the infection and the diagnosis of COVID-19. The R0 and R (e) increase from 1.45 on May 16 to 3.59 on July 5. According to the baseline of normal mobility levels, an increase from -49.6% on May 1st, to -20.6% on July 5 was observed. Based on these data, we conclude that the relaxation of restrictive mobility measures should be reconsidered. Despite this, mobility restrictions must not be a unique mitigation strategy for controlling the Reproductive Index. A comprehensive approach is needed, which generates socio-behavioral changes that allow a further reduction in reproductive rates. Key MessagesO_LIThere is a positive correlation between the reproductive number (R0) and the effective reproductive index (Re) of SARS-CoV-2 and mobility trends in Queretaro, Mexico. C_LIO_LIA clear increase in mobility in the population in Queretaro, Mexico is associated with an increase in the rate of transmission of Covid-19. C_LI

13.
Gynecol Obstet Fertil Senol ; 48(2): 204-210, 2020 02.
Artículo en Francés | MEDLINE | ID: mdl-31923645

RESUMEN

OBJECTIVES: Skeletal remains of pregnant woman whit fetus still in the pelvic region are scarce in the archaeological record. We aimed to review the different cases of maternal and fetal death in the ancient times. METHODS: A review of literature using Medline database and Google about mortality during pregnancy in Prehistory, Antiquity and middle age. The following key words were used: ancient times; paleopathology; immature fetus; medieval; pregnancy; mummies; Antiquity; maternal mortality. RESULTS: Thirty articles were found and we added one personal unpublished case. There were 64 female skeletons with mainly infectious abnormalities (10 dental abscesses and 2 pneumoniae) followed by traumatic lesions (2 frontal fractures and 1 femur luxation). There were 48 fetal remains and 3 twins. We noted 8 obstructed labors (3 breech presentations, 4 transverse lies and one possible shoulder dystocia). CONCLUSIONS: The fact that there were only few cases of maternal deaths with fetal remains raises the questions of the cause of death and the relationship between death and obstetric disorders. Beside the underestimation of these archaecological cases, the reasons of both fetal and maternal death must be looking for among several diseases or anomalies of both or of one of them, related with poor environmental conditions (such as malnutrition and high morbidity from infections) and lack of care the mother and fetus need.


Asunto(s)
Muerte Fetal , Muerte Materna/historia , Femenino , Muerte Fetal/etiología , Historia Antigua , Historia Medieval , Humanos , Muerte Materna/etiología , Mortalidad Materna/historia , Paleopatología , Embarazo
14.
Sci Total Environ ; 686: 322-331, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31181519

RESUMEN

A comparison between monthly CO2 values calculated in the Iberian Peninsula and those measured during six years commencing on October 2010 in the centre of its upper plateau is presented. Gaussian and Epanechnikov kernels are used to calculate CO2 concentration and its growth rate in the study region from values at certain grid points. Slight spatial differences are obtained, revealing that both concentration and growth rate are nearly uniform in the region. However, some intervals were proposed that were represented by bands (strips), distributed meridionally for concentration and zonally for growth rate. Band borders were smoother for the Gaussian kernel than for the Epanechnikov kernel. In addition, the probability distribution function of concentration and growth rate were obtained with both kernels. Temporal analysis is carried out adding a linear evolution for growth rate and a sinusoidal function for the annual cycle. This revealed similar patterns for the region and at the grid point nearest to the measurement site, given by a sinusoidal function with nearly constant amplitude, providing satisfactory agreement. However, measurements showed great dispersion, with the concentration being around 7 ppm higher than for the region. Temporal evolution is characterised by a growth rate of 2.39 ppm yr-1 and a sinusoidal function with an amplitude decrease of 0.25 ppm yr-1.

15.
Arch Environ Contam Toxicol ; 76(2): 331-345, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30430193

RESUMEN

This work analyses levels of particles PM10 and PM2.5 recorded at four air-quality monitoring stations located in the urban area of Valladolid (Spain) during 2015-2016. To achieve this, the evolution of particle concentrations at different time scales was determined. Average concentrations ranged from 15.3 to 17.6 µg m-3 for PM10 and between 8.9 and 14.8 µg m-3 for PM2.5. The highest monthly means were recorded in autumn and winter. The difference between mean concentrations at weekends and on weekdays for PM10 was around 3 µg m-3 at most of the measuring stations and was 1 µg m-3 for PM2.5. Two concentration peaks were found during the day, one in the morning and the other in the evening, which evidenced the influence of traffic and other anthropogenic activities on PM concentrations. Their mean values were approximately 21 and 17-21 µg m-3, respectively, for PM10. Mean maximum values for PM2.5 were 12 µg m-3, except at one of the measuring sites, with 17 µg m-3 for the morning maximum and 1 µg m-3 more for the nocturnal peak. In addition, the impact of long-distance transport of air masses in the study area was analysed by applying a HYSPLIT trajectory model, taking into account backward trajectories of European, African, and Atlantic origins as well as local conditions. In particular, high concentration events due to Saharan dust intrusions are presented. Finally, background levels of particle concentrations estimated at most sampling areas were around 15 and 7.7 µg m-3 for the PM10 and PM2.5 particle fractions, respectively.


Asunto(s)
Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Monitoreo del Ambiente , Tamaño de la Partícula , España
16.
Sci Total Environ ; 627: 417-426, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29426164

RESUMEN

The integrated SCOPE (Soil, Canopy Observation, Photochemistry and Energy balance) model, coupling radiative transfer theory and biochemistry, was applied to a biodiesel crop grown in a Spanish agricultural area. Energy fluxes and CO2 exchange were simulated with this model for the period spanning January 2008 to October 2008. Results were compared to experimental measurements performed using eddy covariance and meteorological instrumentation. The reliability of the model was proven by simulating latent (LE) and sensible (H) heat fluxes, soil heat flux (G), and CO2 exchanges (NEE and GPP). LAI data used as input in the model were retrieved from the MODIS and MERIS sensors. SCOPE was able to reproduce similar seasonal trends to those measured for NEE, GPP and LE. When considering H, the modelled values were underestimated for the period covering July 2008 to mid-September 2008. The modelled fluxes reproduced the observed seasonal evolution with determination coefficients of over 0.77 when LE and H were evaluated. The modelled results offered good agreement with observed data for NEE and GPP, regardless of whether LAI data belonged to MODIS or MERIS, showing slopes of 0.87 and 0.91 for NEE-MODIS and NEE-MERIS, and 0.91 and 0.94 for GPP-MODIS and GPP-MERIS, respectively. Moreover, SCOPE was able to reproduce similar seasonal behaviours to those observed for the experimental carbon fluxes, clearly showing the CO2 sink/source behaviour for the whole period studied.


Asunto(s)
Brassica rapa/fisiología , Monitoreo del Ambiente/métodos , Modelos Teóricos , Ciclo del Carbono , Dióxido de Carbono , Ecosistema , Reproducibilidad de los Resultados , España
17.
J Environ Manage ; 209: 37-45, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29275283

RESUMEN

CO2 and CH4 evolution is usually linked with sources, sinks and their changes. However, this study highlights the role of meteorological variables. It aims to quantify their contribution to the trend of these greenhouse gases and to determine which contribute most. Six years of measurements at a semi-natural site in northern Spain were considered. Three sections are established: the first focuses on monthly deciles, the second explores the relationship between pairs of meteorological variables, and the third investigates the relationship between meteorological variables and changes in CO2 and CH4. In the first section, monthly outliers were more marked for CO2 than for CH4. The evolution of monthly deciles was fitted to three simple expressions, linear, quadratic and exponential. The linear and exponential are similar, whereas the quadratic evolution is the most flexible since it provided a variable rate of concentration change and a better fit. With this last evolution, a decrease in the change rate was observed for low CO2 deciles, whereas an increasing change rate prevailed for the rest and was more accentuated for CH4. In the second section, meteorological variables were provided by a trajectory model. Backward trajectories from 1-day prior to reaching the measurement site were used to calculate distance and direction averages as well as the recirculation factor. Terciles of these variables were determined in order to establish three intervals with low, medium and high values. These intervals were used to classify the variables following their interval widths and skewnesses. The best correlation between pairs of meteorological variables was observed for the average distance, in particular with horizontal wind speed. Sinusoidal relationships with the average direction were obtained for average distance and for vertical wind speed. Finally, in the third section, the quadratic evolution was considered in each interval of all the meteorological variables. As regards the main result, the greatest increases were obtained for high potential temperature for both gases followed by low and medium boundary layer height for CO2 and CH4, respectively. Combining both meteorological variables provided increases of 22 ± 9 and 0.070 ± 0.019 ppm for CO2 and CH4, respectively, although the number of observations affected is small, around 7%.


Asunto(s)
Dióxido de Carbono , Metano , Tiempo (Meteorología) , Contaminantes Atmosféricos , España , Viento
18.
Sci Total Environ ; 593-594: 1-9, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28340476

RESUMEN

The present paper seeks to improve our knowledge concerning the evolution of CO2 and CH4 in terms of monthly trends, growth rate and seasonal variations in the lower atmosphere. Dry continuous measurements of CO2 and the CH4 mixing ratio were carried out over five and a half years (from 15 October 2010 to 29 February 2016) by multi-point sampling at 1.8, 3.7 and 8.3m, using a Picarro analyzer at a rural site in the Low Atmosphere Research Centre (CIBA), on the upper Spanish plateau. Data were divided into diurnal and nocturnal records. The mathematical equation proposed to analyze the overall data was a harmonic one, comprising a polynomial (trend) and a series of harmonics (seasonal cycle). Amplitude was considered as a constant and variable term over time. Quite different behaviour was found between day and night measurements in both climate forcing agents. CO2 showed an accelerating trend in autumn, whereas CH4 trends were higher during the winter. Increasing growth rates were reported for CO2 and CH4 over the whole study period. Nocturnal CO2 amplitudes are higher than diurnal ones except in winter for both gases, and also in the autumn for CH4.

19.
J Mech Behav Biomed Mater ; 65: 200-212, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27591507

RESUMEN

The influence of the orientation of rat bones on their mechanical response is analyzed in this research. 28 femora obtained from 14 Sprague-Dawley rats were subjected to three-point bending tests, comparing the anteroposterior and posteroanterior orientations. The results show that the whole-bone loading capacity of the femora tested in the posteroanterior orientation clearly exceeds that of the anteroposterior oriented bones. Likewise, the intrinsic (tissue-level) loading capacity of the bones tested in the posteroanterior orientation is manifestly higher than that of the bones tested in the opposite direction. The analysis carried out shows that applying beam theory for symmetric cross-sections leads to underestimating the stress state in the cross-section. In this sense, it is generally recommendable to use the non-symmetric beam theory in order to obtain the normal stresses during bending tests. The geometric, intrinsic and global changes resulting from the orientation of the bones was assessed, finding out that it is the variation in the intrinsic properties which explains the change measured in the whole-bone properties. The experimental scope was increased, including 8 additional femora on which a series of Vickers tests were carried out in the anterior and posterior regions of the cross-section. In all cases the hardness obtained in the anterior region is larger than in the posterior region. This result confirms that the mechanical properties of the bone tissue depend on its position in the cross-section and provides a reliable explanation to understand the response of the bones when subjected to bending tests. These results stress the importance of reporting the orientation of the bones in any scientific paper because, otherwise, it would be impossible to properly assess its impact and relevance.


Asunto(s)
Huesos/fisiología , Estrés Mecánico , Animales , Fenómenos Biomecánicos , Ratas , Ratas Sprague-Dawley
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