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1.
J Intern Med ; 294(1): 69-82, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37038609

RESUMEN

INTRODUCTION: After severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, patients may show lung sequelae on radiology and functional impairment at the 1-year follow-up. We aimed to describe the persistence of symptoms, radiological alterations, or reduced diffusing capacity of the lung for carbon monoxide (DLCO ) at 1-year follow-up in patients from the Spanish Registry RECOVID. METHODS: RECOVID collected symptom and radiological and functional lung tests data on hospitalized patients with coronavirus disease 2019 during the acute phase and at the 6- and 12-month follow-up visits. RESULTS: Of the 2500 enrolled survivors (90% admitted to the ward), 1874 had follow-up visits for up to a year. Of these, 42% continued to present with symptoms, 27% had radiological sequelae and 31% had reduced DLCO . Independently associated factors included female sex, asthma and the requirement for invasive or non-invasive mechanical ventilation. Complete radiological resolution was 72.2% at 12 months; associated factors with incomplete recovery were age, male sex, oxygen or respiratory support, corticosteroids and an initial SpO2 /FiO2 <450 or CURB-65 ≥2. Reduced DLCO was observed in 31% of patients at 12 months; associated factors were older age, female sex, smoking habit, SpO2 /FiO2 <450 and CURB-65 ≥2 and the requirement of respiratory support.At 12 months, a proportion of the asymptomatic patients showed reduced DLCO (9.5%), radiological findings (25%) or both (11%). CONCLUSIONS: The factors associated with symptom persistence, incomplete radiological resolution and DLCO <80% differed according to age, sex, comorbidities and respiratory support. The burden of symptoms, reduced DLCO and incomplete radiological resolution were considerable in patients with SARS-CoV-2 pneumonia at the 1-year follow-up after hospitalisation.


Asunto(s)
COVID-19 , Humanos , Masculino , Femenino , SARS-CoV-2 , Pulmón
2.
Respir Res ; 21(1): 42, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-32019550

RESUMEN

BACKGROUND: Obstructive sleep apnoea (OSA) and morbid obesity (MO), defined by a body mass index ≥35 kg/m2, are two closely related conditions. Recent studies suggest that circulating microRNA (miRNA) plays a potential role in the physiopathology of both conditions. To date, circulating miRNA expression has been studied separately in both conditions, but never jointly. The primary treatment of OSA is continuous positive airway pressure (CPAP), whereas bariatric surgery (BS) is the treatment of choice for MO. We have thus initiated the Epigenetics modification in Morbid Obesity and Obstructive Sleep Apnoea (EPIMOOSA) study (ClinicalTrials.gov identifier: NCT03995836). METHODS/DESIGN: EPIMOOSA is a prospective non-interventional cohort study aiming to recruit 45 MO patients who are candidates for BS. Three groups will be formed: MO without OSA, MO with OSA without CPAP and MO with OSA and CPAP. All of them will be followed up in 4 visits: baseline, 6 months prior to BS and 3, 6 and 12 months post-BS. At baseline, OSA status will be assessed by home sleep polygraphy (HSP), and CPAP will be adopted according to national guidelines. A specific standardized questionnaire (including medical conditions and AOS-related symptoms) and anthropometrical examination will be performed at each visit. Blood samples will be obtained at each visit for immediate standard biochemistry, haematology and inflammatory cytokines. For bio-banking, serum, plasma, and circulating exosomes will also be obtained. Twenty-four hours of blood pressure and electrocardiogram (ECG) Holter monitoring will be performed at all visits. A new HSP will be performed at the last visit. Finally, the three groups will be sex- and age- matched with participants in the EPIOSA study, an ongoing study aimed at understanding epigenetic changes in non-obese OSA patients. DISCUSSION: EPIMOOSA will evaluate changes in circulating miRNA in MO with or without OSA for the first time. In addition, EPIMOOSA will be able to elucidate the influence of OSA in MO patients and how specific and combined treatments alter miRNA expression.


Asunto(s)
Epigénesis Genética/genética , Obesidad Mórbida/epidemiología , Obesidad Mórbida/genética , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/genética , Adolescente , Adulto , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , MicroARNs/genética , Persona de Mediana Edad , Obesidad Mórbida/fisiopatología , Estudios Prospectivos , Apnea Obstructiva del Sueño/fisiopatología , Adulto Joven
3.
J Exp Biol ; 221(Pt 2)2018 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-29170257

RESUMEN

In a rare phenomenon, shrews and a few other species cope with seasonal environments by reducing and regrowing brain size, potentially at the cost of changes in cognitive abilities. Here, we confirm an extensive seasonal shrinkage (21.4%) and regrowth (17.0%) of brain mass in winter and spring, respectively, in the common shrew (Sorex araneus L.) in Southern Germany. In a spatial learning task experiment, individuals with reduced winter brain size covered larger distances to find food, compared with the relatively large-brained summer juveniles and regrown spring adults. By reducing their brain mass, these shrews may reduce their energetic demands, but at the cost of cognitive performance, implying a complex trade-off for coping with seasonally fluctuating resources. These results are relevant for our understanding of evolution and the dynamics of mammalian nervous systems in response to environmental changes.


Asunto(s)
Encéfalo/fisiología , Cognición , Musarañas/psicología , Cráneo/anatomía & histología , Factores de Edad , Animales , Femenino , Alemania , Masculino , Estaciones del Año , Musarañas/anatomía & histología , Musarañas/fisiología
4.
J Exp Biol ; 218(Pt 2): 309-15, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25524975

RESUMEN

Recent studies on grasses and sedges suggest that the induction of a mechanism reducing digestibility of plant tissues in response to herbivore damage may drive rodent population cycles. This defence mechanism seems to rely on the abrasive properties of ingested plants. However, the underlying mechanism has not been demonstrated in small wild herbivores. Therefore, we carried out an experiment in which we determined the joint effect of abrasive sedge components on the histological structure of small intestine as well as resting metabolic rate (RMR) of the root vole (Microtus oeconomus). Histological examination revealed that voles fed with a sedge-dominated diet had shorter villi composed from narrower enterocytes in duodenum, jejunum and ileum. Reduction in the height of villi decreased along the small intestine. Activity of the mucus secretion increased along the small intestine and was significantly higher in the ileum. The intestinal abrasion exceeded the compensatory capabilities of voles, which responded to a sedge-dominated diet by a reduction of body mass and a concomitant decrease in whole body RMR. These results explain the inverse association between body mass and the probability of winter survival observed in voles inhabiting homogenous sedge wetlands.


Asunto(s)
Arvicolinae/fisiología , Metabolismo Basal , Mucosa Intestinal/fisiología , Intestino Delgado/anatomía & histología , Animales , Peso Corporal , Carex (Planta)/efectos adversos , Dieta/efectos adversos , Enterocitos , Mucosa Intestinal/metabolismo , Intestino Delgado/fisiología
5.
Intern Emerg Med ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39240412

RESUMEN

Ultrasound has become an increasingly valuable tool for the assessment of body composition, offering several applications and indications in clinical practice. Ultrasound allows bedside evaluation of muscle mass, fat compartments, and extravascular water, providing a cost-effective, portable, and accessible alternative to traditional methods, such as Dual-energy X-ray Absorptiometry (DEXA), Bioelectrical Impedance Analysis (BIA), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI). It is particularly useful in evaluating conditions, such as malnutrition, sarcopenia, and sarcopenic obesity, which require poor muscle mass to establish a diagnosis. The potential uses of ultrasound in body composition assessment include measurement of muscle thickness, cross-sectional area, pennation angle, and echo-intensity, which are indicative of muscle health. Additionally, ultrasound can be used to evaluate various fat compartments, including visceral, subcutaneous, and ectopic fat, which are important for understanding metabolic health and cardiovascular risk. However, the widespread adoption of ultrasound is challenged by the lack of standardized measurements and the absence of ultrasound measures in the validated diagnostic criteria. This article reviews the current applications of ultrasound in body composition assessment, highlighting the recent advancements and the correlation between ultrasound parameters and clinical outcomes. It discusses the advantages of ultrasound while also addressing its limitations, such as the need for standardized protocols and cut-off points. By providing a comprehensive update based on recent publications, this article aims to enhance the clinical utility of ultrasound in assessing and monitoring body composition and pave the way for future research in this field.

6.
Econ Hum Biol ; 49: 101243, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37044041

RESUMEN

This preliminary work presents a first series of heights of male adults in Puerto Rico. The sample, made up of 6000 prisoner records. the estimates were systematically assessed for selectivity, and we find that selectivity is quite negligible for the main results. The text studies the extreme dependence of the standard of living on the evolution of the price of sugar, a dependence which caused the progressive deterioration of material well-being in the country. Only between 1860 and 1880 did Puerto Ricans enjoy some improvement and a higher level of height. We measures the negative short-term effects of the 1898 annexation Puerto Rico by the United States.


Asunto(s)
Estatura , Hispánicos o Latinos , Adulto , Humanos , Masculino , Puerto Rico , Factores Socioeconómicos , Estados Unidos
7.
Front Neuroanat ; 17: 1168523, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37206998

RESUMEN

The common shrew, Sorex araneus, is a small mammal of growing interest in neuroscience research, as it exhibits dramatic and reversible seasonal changes in individual brain size and organization (a process known as Dehnel's phenomenon). Despite decades of studies on this system, the mechanisms behind the structural changes during Dehnel's phenomenon are not yet understood. To resolve these questions and foster research on this unique species, we present the first combined histological, magnetic resonance imaging (MRI), and transcriptomic atlas of the common shrew brain. Our integrated morphometric brain atlas provides easily obtainable and comparable anatomic structures, while transcriptomic mapping identified distinct expression profiles across most brain regions. These results suggest that high-resolution morphological and genetic research is pivotal for elucidating the mechanisms underlying Dehnel's phenomenon while providing a communal resource for continued research on a model of natural mammalian regeneration. Morphometric and NCBI Sequencing Read Archive are available at https://doi.org/10.17617/3.HVW8ZN.

8.
Int J Chron Obstruct Pulmon Dis ; 18: 2473-2481, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37955022

RESUMEN

Background: Chronic obstructive pulmonary disease (COPD) has been associated with worse clinical evolution/survival during a hospitalization for SARS-CoV2 (COVID-19). The objective of this study was to learn the situation of these patients at discharge as well as the risk of re-admission/mortality in the following 12 months. Methods: We carried out a subanalysis of the RECOVID registry. A multicenter, observational study that retrospectively collected data on severe acute COVID-19 episodes and follow-up visits for up to a year in survivors. The data collection protocol includes general demographic data, smoking, comorbidities, pharmacological treatment, infection severity, complications during hospitalization and required treatment. At discharge, resting oxygen saturation (SpO2), dyspnea according to the mMRC (modified Medical Research Council) scale and long-term oxygen therapy prescription were recorded. The follow-up database included the clinical management visits at 6 and 12 months, where re-admission and mortality were recorded. Results: A total of 2047 patients were included (5.6% had a COPD diagnosis). At discharge, patients with COPD had greater dyspnea and a greater need for prescription home oxygen. After adjusting for age, sex and Charlson comorbidity index, patients with COPD had a greater risk of hospital re-admission due to respiratory causes (HR 2.57 [1.35-4.89], p = 0.004), with no significant differences in survival. Conclusion: Patients with COPD who overcome a serious SARS-CoV2 infection show a worse clinical situation at discharge and a greater risk of re-admission for respiratory causes.


Asunto(s)
COVID-19 , Enfermedad Pulmonar Obstructiva Crónica , Insuficiencia Respiratoria , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/terapia , COVID-19/terapia , COVID-19/complicaciones , Estudios Retrospectivos , ARN Viral/uso terapéutico , SARS-CoV-2 , Hospitalización , Disnea/complicaciones , Insuficiencia Respiratoria/diagnóstico , Insuficiencia Respiratoria/terapia , Insuficiencia Respiratoria/complicaciones , Oxígeno
9.
J Digit Imaging ; 25(4): 527-36, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22143412

RESUMEN

Gold chloride technique can be combined with Adobe Photoshop® software to yield a quantitative assessment of the different areas in heterogeneous structures as are ligament. A semi-automatized method based on the sum of two- and three-dimensional morphological criteria upon colorimetric criteria allows the identification and measurement of the area occupied by a structure of interest. It also allows the quantification of color intensity to differentiate structures with similar staining avidity, like vessels and nerves. This computer-assisted, semiquantitative procedure for computerized morphometry is relatively simple to perform. The accuracy, efficiency, and reproducibility of this method based on a commercially available imaging program were considered adequate when tested on the anterior cruciate ligament of the cat. Image normalization by trained observers using a commercially available software package designed for photography, applied to a sample randomly chosen, has provided the means of making reproducible measurements of heterogeneous structures.


Asunto(s)
Técnicas Histológicas/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Fotograbar/métodos , Programas Informáticos , Coloración y Etiquetado/métodos , Animales , Ligamento Cruzado Anterior , Gatos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
10.
Nutr Hosp ; 39(6): 1408-1416, 2022 Dec 20.
Artículo en Español | MEDLINE | ID: mdl-36285583

RESUMEN

Introduction: Background: anthropometric studies have made it possible to measure the evolution of well-being in Spain and under a historical perspective, but the precise effect of income on height has not yet been calculated. Objective: the purpose of this paper is to identify the periods in the life trajectory of young people in which food availability was the most important determinant of their physical growth. Results: the model estimated using ordinary least squares shows that the wage income received by the parents of the young male in the first three years of life and the three years immediately prior to the onset of adolescence explain up to 60 % of his height at the age of 18. All the coefficients of the regressors of the models presented are significant at 0.99 %. According to these calculations, the type of nutrition received by the young person in the period between 11 to 14 years of age was a determining factor in his or her evolutionary process. In addition, the calculations show that food deficiencies were to blame for recurrent periods of loss of well-being, especially in the second half of the 19th century. Conclusion: nutritional deficiencies caused by low wages and poor nutrition have for centuries hampered the physical growth of Castilian youth.


Introducción: Antecedentes: los estudios antropométricos han permitido medir la evolución del bienestar en España y en perspectiva histórica, pero aún no se ha calculado el efecto preciso de los ingresos económicos en la talla. Objetivo: el propósito del este trabajo es identificar los periodos en la trayectoria vital de los jóvenes en los que las disponibilidades alimentación fueron más determinantes en su crecimiento físico. Resultados: el modelo estimado mediante mínimos cuadrados ordinarios demostraría que los ingresos salariales percibidos por sus progenitores por el joven varón en los tres primeros años de vida y los tres inmediatamente anteriores al comienzo de la adolescencia explican hasta un 60 % de su talla al cumplir los 18 años. Todos los coeficientes de los regresores de los modelos planteados son significativos al 0,99 %. Conforme a estos cálculos, el tipo de alimentación del joven en el periodo comprendido entre los 11 y los 14 años fue determinante en su proceso evolutivo. Adicionalmente, los cálculos presentan a las carencias alimentarias como el culpable de los recurrentes periodos de pérdida del bienestar, especialmente en la segunda mitad del siglo XIX. Conclusión: las carencias nutricionales causadas por los bajos salarios y la nutrición deficiente han obstaculizado secularmente el crecimiento físico de los jóvenes castellanos.


Asunto(s)
Renta , Estado Nutricional , Humanos , Adolescente , Femenino , Masculino , Antropometría , Padres , España
11.
R Soc Open Sci ; 9(9): 220652, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36133148

RESUMEN

Seasonal changes in the environment can lead to astonishing adaptations. A few small mammals with exceptionally high metabolisms have evolved a particularly extreme strategy: they shrink before winter and regrow in spring, including changes of greater than 20% in skull and brain size. Whether this process is an adaptation to seasonal climates, resource availability or both remains unclear. We show that European moles (Talpa europaea) also decrease skull size in winter. As resources for closely related Iberian moles (Talpa occidentalis) are lowest in summer, we predicted they should shift the timing of size changes. Instead, they do not change size at all. We conclude that in moles, seasonal decrease and regrowth of skull size is an adaptation to winter climate and not to a changing resource landscape alone. We not only describe this phenomenon in yet another taxon, but take an important step towards a better understanding of this enigmatic cycle.

12.
Ecol Evol ; 12(10): e9447, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36311390

RESUMEN

Global climate change affects many aspects of biology and has been shown to cause body size changes in animals. However, suitable datasets allowing the analysis of long-term relationships between body size, climate, and its effects are rare. The size of the skull is often used as a proxy for overall body size. Skull size does not change much in fully grown vertebrates; however, some high-metabolic small mammals shrink in winter and regrow in spring, including their skull and brain. This is thought to be a winter adaptation, as a smaller brain size reduces energy requirements. Climate could thus affect not only the overall size but also the pattern of the size change, that is, Dehnel's phenomenon, in these animals. We assessed the impact of the changes in climate on the overall skull size and the different stages of Dehnel's phenomenon in skulls of the common shrew, Sorex araneus, collected over 50 years in the Bialowieza Forest, E Poland. Overall skull size decreased, along with increasing temperatures and decreasing soil moisture, which affected the availability of the shrews' main food source, earthworms. The skulls of males were larger than those of females, but the degree of the decrease in size did not differ between sexes. The magnitude of Dehnel's phenomenon increased over time, indicating an increasing selection pressure on animals in winter. Overall, climate clearly affected the common shrew's overall size as well as its seasonal size changes. With the current acceleration in climate change, the effects on the populations of this cold-adapted species may be quite severe in a large part of its distribution range.

13.
Curr Biol ; 31(10): R463-R465, 2021 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-34033763

RESUMEN

Lázaro and Dechmann explain how some mammals that live through harsh winters exhibit seasonal shrinkage of the brain and skull, a process called Dehnel's phenomenon, which helps to spare energy during times of food shortage and high energetic demands.


Asunto(s)
Encéfalo , Mamíferos , Cráneo , Animales , Metabolismo Energético , Estaciones del Año
14.
Ecol Evol ; 11(6): 2431-2448, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33767812

RESUMEN

Some small mammals exhibit Dehnel's Phenomenon, a drastic decrease in body mass, braincase, and brain size from summer to winter, followed by a regrowth in spring. This is accompanied by a re-organization of the brain and changes in other organs. The evolutionary link between these changes and seasonality remains unclear, although the intensity of change varies between locations as the phenomenon is thought to lead to energy savings during winter.Here we explored geographic variation of the intensity of Dehnel's Phenomenon in Sorex araneus. We compiled literature on seasonal changes in braincase size, brain, and body mass, supplemented by our own data from Poland, Germany, and Czech Republic.We analyzed the effect of geographic and climate variables on the intensity of change and patterns of brain re-organization.From summer to winter, the braincase height decreased by 13%, followed by 10% regrowth in spring. For body mass, the changes were -21%/+82%, respectively. Changes increased toward northeast. Several climate variables were correlated with these transformations, confirming a link of the intensity of the changes with environmental conditions. This relationship differed for the decrease versus regrowth, suggesting that they may have evolved under different selective pressures.We found no geographic trends explaining variability in the brain mass changes although they were similar (-21%/+10%) to those of the braincase size. Underlying patterns of change in brain organization in northeastern Poland were almost identical to the pattern observed in southern Germany. This indicates that local habitat characteristics may play a more important role in determining brain structure than broad scale geographic conditions.We discuss the techniques and criteria used for studying this phenomenon, as well as its potential presence in other taxa and the importance of distinguishing it from other kinds of seasonal variation.

15.
Injury ; 52(4): 747-749, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33059927

RESUMEN

INTRODUCTION: Mountain running races have grown in popularity in the recent years. Nonetheless, there are few studies on injuries and injury rates. Moreover, these studies have focused on long-distance events such as ultramarathons (>42 km). Therefore, the aim of the present study was to examine the severity, type, and body location of musculoskeletal injuries during 20-42 km mountain running races. In addition, the injury rates in this type of races were examined. METHODS: Data on injuries were collected during 36 mountain running races over 5 consecutive seasons from 2015 to 2019. The participants reported all musculoskeletal injuries on a standardized injury report form. The results were presented as the number of injuries per 1000 h exposure and per 1000 participants. RESULTS: Twenty eight injuries were reported. Most injuries occurred in the ankle (32%) followed by the knee (14%) and foot/toe (11%). The number of injuries represented an overall injury rate of 1.6 injuries per 1000 h running and 5.9 injuries per 1000 runners. The case fatality rate was 0. CONCLUSIONS: The incidence of musculoskeletal injuries during 20-42 km mountain running races is low. In addition, the majority of injuries experienced by runners are minor in nature and located in lower extremities, mainly the ankles.


Asunto(s)
Traumatismos en Atletas , Carrera , Traumatismos en Atletas/epidemiología , Pie , Humanos , Incidencia , Extremidad Inferior/lesiones , Estaciones del Año
16.
Endocrinol Diabetes Nutr (Engl Ed) ; 67(8): 509-516, 2020 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32620517

RESUMEN

INTRODUCTION: Obstructive sleep apnea (OSA) has a high incidence in patients with morbid obesity who are candidates for bariatric surgery (BS). Adequate screening would decrease the number of respiratory polygraphies (RPs). OBJECTIVE: To analyze the value of a sequential model consisting of a questionnaire (modified Dixon [DXM] vs STOP-Bang) and nocturnal pulse oximetry in patients who were candidates for BS. METHODS: A prospective study was conducted from July 1, 2014 to July 1, 2015 on candidates for BS, excluding those who have already undergone RP. VARIABLES: questionnaires (Epworth, STOP-Bang, and DXM), anthropometric measurements, RP, and blood and gas tests. The sample was divided into patients with no or mild OSA (no OSA) and those with moderate to severe OSA (AHI>15). RESULTS: A total of 70 patients were analyzed, 46 (65.7%) of them females. Moderate to severe OSA was diagnosed in 26 (37.1%) patients. STOP-Bang and DXM were compared using ROC curves, and greater area under the curve (AUC) was found for the latter (0.873 [0.74 -0.930] vs 0.781 [0.673-0.888]). STOP-Bang had greater sensitivity, 100%, as compared to 73.1% for DXM. ODI3% showed greater diagnostic yield (AUC=0.982 [0.970-1]). Use of the sequential model with STOP-Bang>3, DXM>5, and DXM>3 would have avoided 41 (58.5%), 50 (71.4%), and 41 (58.5%) RPs and 0, 7 (10%), and 0 false negatives, respectively. CONCLUSION: Use of a sequential model based on the STOP-Bang and nocturnal pulse oximetry is a useful tool for screening OSA in patients with morbid obesity candidates for BS, decreasing the number of RPs.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida/complicaciones , Obesidad Mórbida/cirugía , Oximetría , Autoinforme , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/diagnóstico , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Modelos Teóricos , Estudios Prospectivos , Sensibilidad y Especificidad
17.
R Soc Open Sci ; 7(4): 191989, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32431881

RESUMEN

Small endothermic mammals have high metabolisms, particularly at cold temperatures. In the light of this, some species have evolved a seemingly illogical strategy: they reduce the size of the brain and several organs to become even smaller in winter. To test how this morphological strategy affects energy consumption across seasonally shifting ambient temperatures, we measured oxygen consumption and behaviour in the three seasonal phenotypes of the common shrew (Sorex araneus), which differ in size by about 20%. Body mass was the main driver of oxygen consumption, not the reduction of metabolically expensive brain mass. Against our expectations, we found no change in relative oxygen consumption with low ambient temperature. Thus, smaller body size in winter resulted in significant absolute energy savings. This finding could only partly be explained by an increase of lower cost behaviours in the activity budgets. Our findings highlight that these shrews manage to avoid one of the most fundamental and intuitive rules of ecology, allowing them to subsist with lower resource availability and successfully survive the harsh conditions of winter.

18.
Sci Rep ; 9(1): 2489, 2019 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-30792434

RESUMEN

The growth of the vertebrate skull and brain is usually unidirectional and more or less stops when animals are adult. Red-toothed shrews break this rule. They seasonally shrink and regrow brain and skull size by 20% or more, presumably to save energy when conditions are harsh. The size change is anticipatory of environmental change and occurs in all individuals, but it is unknown whether its extent can be modulated by environmental conditions. We kept shrews under different conditions, monitored seasonal changes in skull size with series of X-rays, and compared them with free ranging animals. We found extensive differences in the pattern of skull size change between experimental groups. Skull size of shrews kept at constant temperature showed a steady decline, while the skull size changes of free ranging shrews and captive individuals exposed to natural temperature regimes were identical. In contrast, body mass never reached the spring values of free ranging shrews in either captive regime. The extent of this adaptive seasonal pattern can thus be flexibly adapted to current environmental conditions. Combining reversible size changes with such strong phenotypic plasticity may allow these small, non-hibernating predators with high metabolic rates to continue being successful in today's changing environments.


Asunto(s)
Encéfalo/anatomía & histología , Musarañas/fisiología , Cráneo/anatomía & histología , Adaptación Fisiológica , Animales , Encéfalo/fisiología , Estaciones del Año , Musarañas/anatomía & histología , Cráneo/fisiología , Rayos X
19.
Brain Struct Funct ; 223(6): 2823-2840, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29663134

RESUMEN

The seasonal changes in brain size of some shrews represent the most drastic reversible transformation in the mammalian central nervous system known to date. Brain mass decreases 10-26% from summer to winter and regrows 9-16% in spring, but the underlying structural changes at the cellular level are not yet understood. Here, we describe the volumetric differences in brain structures between seasons and sexes of the common shrew (Sorex araneus) in detail, confirming that changes in different brain regions vary in the magnitude of change. Notably, shrews show a decrease in hypothalamus, thalamus, and hippocampal volume and later regrowth in spring, whereas neocortex and striatum volumes decrease in winter and do not recover in size. For some regions, males and females showed different patterns of seasonal change from each other. We also analyzed the underlying changes in neuron morphology. We observed a general decrease in soma size and total dendrite volume in the caudoputamen and anterior cingulate cortex. This neuronal retraction may partially explain the overall tissue shrinkage in winter. While not sufficient to explain the entire seasonal process, it represents a first step toward understanding the mechanisms beneath this remarkable phenomenon.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/fisiología , Vías Nerviosas/fisiología , Neuronas/citología , Estaciones del Año , Musarañas/anatomía & histología , Factores de Edad , Animales , Mapeo Encefálico/métodos , Dendritas/ultraestructura , Femenino , Masculino , Vías Nerviosas/ultraestructura , Neuronas/clasificación , Factores Sexuales , Tinción con Nitrato de Plata
20.
Emergencias ; 30(1): 21-27, 2018 02.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29437306

RESUMEN

OBJECTIVES: Because of high rates of resistance to fluoroquinolones, ceftriaxone has become one of the main options for treating febrile urinary tract infection (FUTI). This study aimed to identify predictors of ceftriaxone resistance in community-acquired FUTIs in men. MATERIAL AND METHODS: Cross-sectional ambispective study enrolling men with FUTIs treated in the emergency department of a local area hospital in Spain. RESULTS: A total of 552 FUTI episodes were studied; 103 (18.6%) were caused by a ceftriaxone-resistant microorganism. Variables associated with a ceftriaxone-resistant FUTI were older age, health care-associated FUTI, dementia, diabetes mellitus, neoplasms, a history of UTIs, urologic disease, and complicated FUTI. Patients with ceftriaxone-resistant FUTIs also had higher rates of recent antibiotic treatment. Independent variables associated with FUTI due to a ceftriaxoneresistant microorganism were cirrhosis of the liver (odds ratio [OR], 6,00 95% CI, 1.25-28; P = .025), health careassociated FUTI (OR, 2.3 95% CI, 1.23-4.27; P = .009), and prior treatment with antibiotics (OR, 2.15; 95% CI, 1.23-3.76 P = .007). Components of health care-associated FUTI were a history of admission to a long-term residence (OR, 2.90 95% CI, 1.21-7.16; P = .017) and use of penicillins with or without beta-lactamase inhibitors (OR, 2.16; 95% CI, 1.05-4.42; P = .035). CONCLUSION: Cirrhosis of the liver; history of health care-associated FUTI, especially in patients residing in a long-term care facility; and recent use of antibiotics, mainly penicillins with or without beta-lactamase inhibitors, are risk factors for ceftriaxone-resistant FUTI in men.


OBJETIVO: Las elevadas tasas de resistencia a fluoroquinolonas han hecho de la ceftriaxona una de las principales opciones terapéuticas en las infecciones del tracto urinario febriles (ITUF). El objetivo del estudio es identificar factores predictivos de infección por microorganismos resistentes a ceftriaxona (MRC) en ITUF comunitaria en hombres. METODO: Estudio transversal ambispectivo en el que se incluyeron hombres con ITUF atendidos en el servicio de urgencias de un hospital comarcal. RESULTADOS: Se incluyeron 552 episodios de ITUF, 103 (18,6%) causadas por MRC. Los pacientes con ITUF por MRC tenían mayor edad, más frecuencia de ITUF relacionada con la atención sanitaria (ITUF-AS), demencia, diabetes mellitus, neoplasia, ITU previa, patología urológica, ITUF complicada y antecedente de tratamiento antibiótico reciente. Las variables independientemente asociadas a ITUF por MRC fueron la cirrosis hepática (OR 6,00; IC 95%: 1,25-28; p = 0,025), tener una ITUF-AS (OR 2,3; IC 95%: 1,23-4,27; p = 0,009) y el consumo previo de antibióticos (OR 2,15; IC 95%: 1,23-3,76; p = 0,007). Entre los componentes de la ITUF-AS, el antecedentes de estancia en centro larga estancia (OR 2,90; IC 95%: 1,21-7,16; p = 0,017) y entre los antibióticos el consumo de penicilinas con/sin inhibidores de betalactamasa (OR 2,16; IC 95%: 1,05-4,42; p = 0,035) se asociaron a ITUF por MRC. CONCLUSIONES: La cirrosis, presentar una ITUF-AS, especialmente provenir de un centro de larga estancia, y el consumo reciente de antibióticos, principalmente de penicilinas con/sin inhibidores de betalactamasa, son factores de riesgo de ITUF por MRC en hombres.


Asunto(s)
Ceftriaxona/farmacología , Farmacorresistencia Microbiana , Infecciones Urinarias/tratamiento farmacológico , Anciano , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Estudios Transversales , Servicio de Urgencia en Hospital , Fiebre/etiología , Humanos , Cirrosis Hepática/complicaciones , Masculino , Persona de Mediana Edad , Penicilinas/farmacología , Factores de Riesgo , Infecciones Urinarias/complicaciones , Infecciones Urinarias/microbiología , Resistencia betalactámica , Inhibidores de beta-Lactamasas/farmacología
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