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Complex cognitive abilities are thought to arise from the ability of the brain to adaptively reconfigure its internal network structure as a function of task demands. Recent work has suggested that this inherent flexibility may in part be conferred by the widespread projections of the ascending arousal systems. While the different components of the ascending arousal system are often studied in isolation, there are anatomical connections between neuromodulatory hubs that we hypothesise are crucial for mediating key features of adaptive network dynamics, such as the balance between integration and segregation. To test this hypothesis, we estimated the strength of structural connectivity between key hubs of the noradrenergic and cholinergic arousal systems (the locus coeruleus [LC] and nucleus basalis of Meynert [nbM], respectively). We then asked whether the strength of structural LC and nbM inter-connectivity was related to individual differences in the emergent, dynamical signatures of functional integration measured from resting state fMRI data, such as network and attractor topography. We observed a significant positive relationship between the strength of white-matter connections between the LC and nbM and the extent of network-level integration following BOLD signal peaks in LC relative to nbM activity. In addition, individuals with denser white-matter streamlines interconnecting neuromodulatory hubs also demonstrated a heightened ability to shift to novel brain states. These results suggest that individuals with stronger structural connectivity between the noradrenergic and cholinergic systems have a greater capacity to mediate the flexible network dynamics required to support complex, adaptive behaviour. Furthermore, our results highlight the underlying static features of the neuromodulatory hubs can impose some constraints on the dynamic features of the brain.
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Núcleo Basal de Meynert , Encéfalo , Colinérgicos , Humanos , Locus Coeruleus/diagnóstico por imagen , Imagen por Resonancia Magnética/métodosRESUMEN
INTRODUCTION: Caring for a significant other during cancer treatment can be demanding. Little is known about the well-being of informal caregivers of patients with colon cancer. This study aims to examine informal caregiver well-being during adjuvant chemotherapy for colon cancer. MATERIAL AND METHODS: This exploratory longitudinal, prospective study measured the course of informal caregiver burden (Self-Perceived Pressure of Informal Care), distress (Hospital Anxiety and Depression Scale), health-related quality of life (RAND-36), marital satisfaction (Maudsley Marital Questionnaire), social support (Social Support List - Discrepancies), fatigue (Abbreviated Fatigue Questionnaire), and self-esteem (Caregiver Reaction Assessment) before (T0), during (T1), and after (T2) patients' treatment. RESULTS: Baseline data of 60 out of 76 eligible dyads (79%) were analyzed. Mean levels of informal caregiver burden and distress improved significantly over time, as did their health-related quality of life and perceived social support. At baseline, 30% and 26.7% of informal caregivers reported moderate-to-high levels of burden and clinically relevant levels of distress, respectively, which changed to 20% and 18.8% at T2. Informal caregiver burden and distress at baseline were the strongest predictors of informal caregiver burden and distress during and following patients' treatment, respectively. CONCLUSION: When informal caregivers and patients experience problems before start of adjuvant chemotherapy, problems seem to improve over time. Approximately 20% of informal caregivers remain burdened and distressed after patients' end of treatment. Paying attention to baseline distress and burden seems indicated, as these were strong predictors of informal caregivers' well-being during and after treatment.
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Cuidadores/psicología , Quimioterapia Adyuvante/métodos , Neoplasias del Colon/tratamiento farmacológico , Calidad de Vida/psicología , Apoyo Social , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
We report the case of a 60-year old female patient with advanced severe lung injury as a consequence of COVID-19-pneumonia. The patient was initially treated with highflow oxygen via nasal cannula (HFNC) and CPAP for two days but had to be intubated and mechanically ventilated. After failure of mechanical ventilation because of persistant severe hypoxemia treatment was switched to ECMO which was applicated for 24 days. Prognostic parameters indicated a favourable trend after day 14. After discontinuation of ECMO and 11 days of intermittent assisted ventilation via tracheostoma and low dose oxygen (1âl/min), the patient could be transferred to rehabilitation. The last chest radiograph prior to transferral revealed a nearly complete resolution of bilateral pulmonary infiltrates. Our case demonstrates that severe COVID-19-associated lung injury can be reversible even after prolonged ECMO.
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Infecciones por Coronavirus/complicaciones , Coronavirus , Oxigenación por Membrana Extracorpórea/métodos , Neumonía Viral/complicaciones , Síndrome de Dificultad Respiratoria/terapia , Insuficiencia Respiratoria/terapia , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/virología , Femenino , Humanos , Pulmón/fisiopatología , Persona de Mediana Edad , Pandemias , Neumonía Viral/virología , Síndrome de Dificultad Respiratoria/etiología , SARS-CoV-2 , Resultado del TratamientoRESUMEN
Scanning transmission electron microscopy (STEM) at low primary electron energies has received increasing attention in recent years because knock-on damage can be avoided and high contrast for weakly scattering materials is obtained. However, the broadening of the electron beam in the sample is pronounced at low electron energies, which degrades resolution and limits the maximum specimen thickness. In this work, we have studied electron beam broadening in materials with atomic numbers Z between 10 and 32 (MgO, Si, SrTiO3 , Ge) and thicknesses up to 900 nm. Beam broadening is directly measured using a multisegmented STEM detector installed in a scanning electron microscope at electron energies between 15 and 30 keV. For experimental reasons, the electron beam diameter is defined to contain only 68% of the total intensity instead of the commonly used 90% of the total beam intensity. The measured beam diameters can be well described with calculated ones based on a recently published model by Gauvin and Rudinsky. Using the concept of anomalous diffusion the Hurst exponent H is introduced that varies between 0.5 and 1 for different scattering regimes depending on t/Λel with the specimen thickness t and the elastic mean free path length Λel . The calculations also depend on the fraction of the beam intensity that defines the electron beam diameter. A Hurst exponent H of 1 is characteristic for the ballistic scattering regime with t/Λel â 0 and can be excluded for the experimental conditions of our study with 6 ⦠t/Λel ⦠30. We deduced H = 0.75 from measured beam diameters which is larger than H = 0.5 that is expected under diffusion conditions. The deviation towards larger H values can be rationalised by our definition of electron diameter that contains only 68% of the total beam intensity and requires therefore larger sample thicknesses before the diffusion regime is reached. Our results clearly deviate from previous analytical approaches to describe beam broadening (Goldstein et al., Reed, Williams et al., Kohl and Reimer). Measured beam diameters are compared with simulated ones, which are obtained by solving the electron transport equation. This approach is advantageous compared to the commonly used Monte Carlo simulations because it is an exact solution of the electron transport equation and requires less computer time. Simulated beam diameter agree well with the experimental data and yield H = 0.80. LAY DESCRIPTION: In scanning transmission electron microscopy (STEM), a focused electron beam is scanned over an electron-transparent sample and an image is formed by detecting the intensity of the transmitted electrons by a STEM detector. STEM resolution is ultimately limited by the electron beam diameter and can be better than 0.1 nm for the best microscopes. However, the electron-beam diameter increases with increasing specimen thickness because electrons are scattered by the interaction of the specimen material and electrons. Electron scattering leads to a change of the electron propagation direction and reduces focusing of the electron beam. The associated electron-beam broadening degrades the lateral resolution of STEM and generally limits the maximum specimen thickness that can be imaged with good resolution. STEM is up to now mainly performed at high electron energies of 80 keV and above. Lower electron energies are beneficial for the study of weakly scattering and radiation-sensitive materials but electron beam broadening becomes more pronounced with decreasing electron energies. Knowledge of beam broadening is therefore particularly important for the interpretation of STEM images that are taken with low-energy electrons. In this work we have studied electron-beam broadening in different materials with thicknesses up to 900 nm at low electron energies between 15 and 30 keV. Beam broadening is directly measured with a newly developed technique. We compare measured beam diameters with different models on beam broadening from literature and find that only a recently published model is well suited to describe the experimental results under our experimental conditions. In addition, beam broadening is simulated by modelling electron propagation in the specimen. The simulation results agree well with the measured beam diameters.
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BACKGROUND: Dipyrone (metamizole) is widely used for perioperative pain management in countries where it is marketed; however, uncertainty exists concerning the safe use of this drug, specifically considering the rare adverse event of an agranulocytosis. METHODS: As evidence from published studies was lacking, an expert panel developed recommendations for the perioperative use of dipyrone. After a formal, structured consensus process, the recommendations were approved by the involved medical societies. RESULTS: The panel agreed that blood cell counts shall not be standard for short-term perioperative use in patients unless they are at risk for neutropenia. The medical staff shall be aware of the symptoms and course of action when agranulocytosis is suspected. Patients shall be informed about the risks and benefits of dipyrone and about potential alternatives. The expert group concluded that dipyrone has a relatively positive risk-benefit ratio compared to other nonopioid analgesics. The group strongly recommended educating patients about the symptoms of agranulocytosis if they have received dipyrone over several days and/or treatment is to be continued after discharge, because agranulocytosis can occur several days after discontinuation of metamizole. Further recommendations refer to the information of the physician taking over the patient's care after discharge and the avoidance of re-exposure in patients having previously suffered from dipyrone-induced agranulocytosis. CONCLUSION: The group's recommendations shall be communicated in order to raise medical staff's and patients' awareness of the appropriate use of dipyrone in the perioperative period.
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Agranulocitosis , Dipirona , Dolor Agudo/tratamiento farmacológico , Dolor Agudo/prevención & control , Agranulocitosis/inducido químicamente , Agranulocitosis/prevención & control , Analgésicos/administración & dosificación , Analgésicos/efectos adversos , Anestesiología/normas , Asociación , Cuidados Críticos , Dipirona/administración & dosificación , Dipirona/efectos adversos , Humanos , Periodo PerioperatorioRESUMEN
BACKGROUND: Dipyrone (metamizole) is widely used for perioperative pain management in countries where it is marketed; however, uncertainty exists concerning the safe use of this drug, specifically considering the rare adverse event of an agranulocytosis. METHODS: As evidence from published studies was lacking, an expert panel developed recommendations for the perioperative use of dipyrone. After a formal, structured consensus process, the recommendations were approved by the involved medical societies. RESULTS: The panel agreed that blood cell counts shall not be standard for short-term perioperative use in patients unless they are at risk for neutropenia. The medical staff shall be aware of the symptoms and course of action when agranulocytosis is suspected. Patients shall be informed about the risks and benefits of dipyrone and about potential alternatives. The expert group concluded that dipyrone has a relatively positive risk-benefit ratio compared to other nonopioid analgesics. The group strongly recommended educating patients about the symptoms of agranulocytosis if they have received dipyrone over several days and/or treatment is to be continued after discharge, because agranulocytosis can occur several days after discontinuation of metamizole. Further recommendations refer to the information of the physician taking over the patient's care after discharge and the avoidance of re-exposure in patients having previously suffered from dipyrone-induced agranulocytosis. CONCLUSION: The group's recommendations shall be communicated in order to raise medical staff's and patients' awareness of the appropriate use of dipyrone in the perioperative period.
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Dolor Agudo/tratamiento farmacológico , Agranulocitosis/inducido químicamente , Analgésicos no Narcóticos/uso terapéutico , Dipirona/uso terapéutico , Periodo Perioperatorio , Sociedades Médicas , Analgésicos no Narcóticos/efectos adversos , Anestesiología , Dipirona/efectos adversos , Alemania , Humanos , SuizaRESUMEN
Medical confidentiality is a fundamental prerequisite in the patient-physician relationship based on trust and goes back to the Hippocratic oath. It is clearly defined in the German Constitution as well as the medical professional code of conduct. A breach of confidentiality can result in criminal sanctions and professional consequences as well as civil claims for damages and compensation by the affected patients. In routine clinical practice situations repeatedly occur which lead to uncertainty regarding the limits of confidentiality, the right to silence and the obligation to disclosure. The purpose of this article is to explain the legal foundations of medical confidentiality, the right to silence and the obligation to disclosure and to provide practical support for critical questions in routine clinical practice.
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Confidencialidad , Revelación , Humanos , Relaciones Médico-PacienteRESUMEN
KEY MESSAGE: Simultaneous improvement of protein content and grain yield by index selection is possible but its efficiency largely depends on the weighting of the single traits. The genetic architecture of these indices is similar to that of the primary traits. Grain yield and protein content are of major importance in durum wheat breeding, but their negative correlation has hampered their simultaneous improvement. To account for this in wheat breeding, the grain protein deviation (GPD) and the protein yield were proposed as targets for selection. The aim of this work was to investigate the potential of different indices to simultaneously improve grain yield and protein content in durum wheat and to evaluate their genetic architecture towards genomics-assisted breeding. To this end, we investigated two different durum wheat panels comprising 159 and 189 genotypes, which were tested in multiple field locations across Europe and genotyped by a genotyping-by-sequencing approach. The phenotypic analyses revealed significant genetic variances for all traits and heritabilities of the phenotypic indices that were in a similar range as those of grain yield and protein content. The GPD showed a high and positive correlation with protein content, whereas protein yield was highly and positively correlated with grain yield. Thus, selecting for a high GPD would mainly increase the protein content whereas a selection based on protein yield would mainly improve grain yield, but a combination of both indices allows to balance this selection. The genome-wide association mapping revealed a complex genetic architecture for all traits with most QTL having small effects and being detected only in one germplasm set, thus limiting the potential of marker-assisted selection for trait improvement. By contrast, genome-wide prediction appeared promising but its performance strongly depends on the relatedness between training and prediction sets.
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Grano Comestible/crecimiento & desarrollo , Fitomejoramiento , Selección Genética , Triticum/genética , Mapeo Cromosómico , Grano Comestible/genética , Europa (Continente) , Estudios de Asociación Genética , Variación Genética , Genotipo , Modelos Genéticos , Fenotipo , Sitios de Carácter Cuantitativo , Triticum/crecimiento & desarrolloRESUMEN
The Functional Annotation of Animal Genomes (FAANG) project aims to identify genomic regulatory elements in both sexes across multiple stages of development in domesticated animals. This study represents the first stage of the FAANG project for the horse, Equus caballus. A biobank of 80 tissue samples, two cell lines and six body fluids was created from two adult Thoroughbred mares. Ante-mortem assessments included full physical examinations, lameness, ophthalmologic and neurologic evaluations. Complete blood counts and serum biochemistries were also performed. At necropsy, in addition to tissue samples, aliquots of serum, ethylenediaminetetraacetic acid (EDTA) plasma, heparinized plasma, cerebrospinal fluid, synovial fluid, urine and microbiome samples from all regions of the gastrointestinal and urogenital tracts were collected. Epidermal keratinocytes and dermal fibroblasts were cultured from skin samples. All tissues were grossly and histologically evaluated by a board-certified veterinary pathologist. The results of the clinical and pathological evaluations identified subclinical eosinophilic and lymphocytic infiltration throughout the length of the gastrointestinal tract as well as a mild clinical lameness in both animals. Each sample was cryo-preserved in multiple ways, and nuclei were extracted from selected tissues. These samples represent the first published systemically healthy equine-specific biobank with extensive clinical phenotyping ante- and post-mortem. The tissues in the biobank are intended for community-wide use in the functional annotation of the equine genome. The use of the biobank will improve the quality of the reference annotation and allow all equine researchers to elucidate unknown genomic and epigenomic causes of disease.
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Bancos de Muestras Biológicas , Genómica , Caballos/genética , Animales , Femenino , FenotipoRESUMEN
Anxiety and depressive symptoms have adverse effects on children's development. The present study investigates the associations of socioeconomic factors as well as maternal emotional health with children's emotional health status. The data were collected between 2011 and 2015 in the LIFE Child study, a population-based cohort study in Leipzig, Germany. The emotional health status of 1093 children (2.5-11.9 years old) was investigated using the subscale 'emotional problems' of the Strengths and Difficulties Questionnaire. Associations of maternal emotional health, family status, and socioeconomic status (SES) with the emotional health status of children were estimated via regression analyses. 21.13% of the participating children were assigned to the 'risk' group for emotional problems. The results furthermore revealed that children of mothers reporting more depressive symptoms, children living in single-parent families, and children of families with lower SES scored higher in the emotional problems scale. When considering the different indicators of SES (parental education, occupational status, and monthly net income) separately, only income showed significant associations with children's emotional health status. The prevalence of emotional problems in children in Leipzig, a city in East Germany, appears to be higher than the previously reported German average. Maternal depressive symptoms, single-parent families, lower SES, and especially lower income can be seen as risk factors for children's emotional health.
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Salud Infantil/economía , Niño , Preescolar , Estudios de Cohortes , Emociones , Femenino , Humanos , Masculino , Factores Protectores , Factores de Riesgo , Clase SocialRESUMEN
We report the first documented case of an inguinal hernia containing bladder, resulting in contralateral allograft hydroureteronephrosis. A 39-year-old male patient presented with allograft dysfunction, a contralateral inguinoscrotal hernia, and marked hydroureteronephrosis on ultrasound (US). Percutaneous nephrostogram and a retrograde cystogram suggested bladder herniation with incorporation of the contralateral ureteroneocystostomy into the hernia. Paraperitoneal bladder herniation was confirmed at surgery and hernioplasty was performed. Six-week follow-up revealed normal renal function with no sign of hernia recurrence. Despite occurring rarely, transplant ureter or bladder herniation should be considered in the differential diagnosis of hydroureteronephrosis. This case illustrates that the contralateral position of hernia to allograft does not necessarily preclude the hernia as the source of ureteric obstruction.
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Hernia Inguinal/complicaciones , Hidronefrosis/etiología , Vejiga Urinaria/cirugía , Incontinencia Urinaria/etiología , Adulto , Aloinjertos , Humanos , Masculino , Resultado del TratamientoRESUMEN
BACKGROUND: Hand-foot syndrome (HFS) is a common side-effect of capecitabine. S-1 is an oral fluoropyrimidine with comparable efficacy to capecitabine in gastrointestinal cancers but associated with a lower incidence of HFS in Asian patients. This study compares the incidence of HFS between S-1 and capecitabine as first-line treatment in Western metastatic colorectal cancer (mCRC) patients. PATIENTS AND METHODS: Patients with previously untreated mCRC and planned treatment with fluoropyrimidine monochemotherapy were randomized 1 : 1 to receive either capecitabine (1250 mg/m2 orally for patients <70 years; 1000 mg/m2 for patients ≥70 years, twice daily on days 1-14) or S-1 (30 mg/m2 orally twice daily on days 1-14) in 3-weekly cycles, with bevacizumab optional in both groups. The primary endpoint was the incidence of any grade HFS, as assessed by both physicians and patients (diaries). Secondary endpoints included grade 3 HFS, other toxicities, relative dose intensity, progression-free survival, response rate and overall survival. RESULTS: A total of 161 patients were randomized in 27 centres. The incidence of any grade HFS as assessed by physicians was 73% in the capecitabine group (n = 80) and 45% in the S-1 group (n = 80) [odds ratio (95% confidence interval) 0.31 (0.16-0.60), P = 0.0005]. The incidence of grade 3 HFS was 21% and 4% (P = 0.003), respectively. Patient-assessed any grade HFS was 84% and 58%, respectively (P = 0.004). Grade 3 anorexia was more common in the S-1 group (3% versus 13%, P = 0.03). Median relative dose intensity was 88% in the capecitabine group and 95% in the S-1 group (P = 0.026). There were no statistically significant differences in median progression-free survival, response rate and overall survival rates. CONCLUSION: Treatment with S-1 in Western mCRC patients is associated with a significantly lower incidence of HFS compared with capecitabine, with comparable efficacy. CLINICALTRIALS.GOV REGISTRATION NUMBER: NCT01918852.
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Capecitabina/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Ácido Oxónico/uso terapéutico , Tegafur/uso terapéutico , Anciano , Combinación de Medicamentos , Femenino , Humanos , MasculinoRESUMEN
The mechanisms underlying pathologically synchronized neural oscillations in Parkinson's disease (PD) and generalized epilepsies are explored in parallel via a physiologically-based neural field model of the corticothalamic-basal ganglia (CTBG) system. The basal ganglia (BG) are approximated as a single effective population and their roles in the modulation of oscillatory dynamics of the corticothalamic (CT) system and vice versa are analyzed. In addition to normal EEG rhythms, enhanced activity around 4 Hz and 20 Hz exists in the model, consistent with the characteristic frequencies observed in PD. These rhythms result from resonances in loops formed between the BG and CT populations, analogous to those that underlie epileptic oscillations in a previous CT model, and which are still present in the combined CTBG system. Dopamine depletion is argued to weaken the dampening of these loop resonances in PD, and network connections then explain the significant coherence observed between BG, thalamic, and cortical population activity around 4-8 Hz and 20 Hz. Parallels between the afferent and efferent connection sites of the thalamic reticular nucleus (TRN) and BG predict low dopamine to correspond to a reduced likelihood of tonic-clonic (grand mal) seizures, which agrees with experimental findings. Furthermore, the model predicts an increased likelihood of absence (petit mal) seizure resulting from pathologically low dopamine levels in accordance with experimental observations. Suppression of absence seizure activity is demonstrated when afferent and efferent BG connections to the CT system are strengthened, which is consistent with other CTBG modeling studies. The BG are demonstrated to have a suppressive effect on activity of the CTBG system near tonic-clonic seizure states, which provides insight into the reported efficacy of current treatments in BG circuits. Sleep states of the TRN are also found to suppress pathological PD activity in accordance with observations. Overall, the findings demonstrate strong parallels between coherent oscillations in generalized epilepsies and PD, and provide insights into possible comorbidities.
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Encéfalo/fisiopatología , Epilepsia Generalizada/fisiopatología , Modelos Neurológicos , Enfermedad de Parkinson/fisiopatología , Potenciales de Acción/fisiología , Ganglios Basales/fisiopatología , Ondas Encefálicas/fisiología , Humanos , Tálamo/fisiopatologíaRESUMEN
BACKGROUND: The regular update of the guidelines on fibromyalgia syndrome, AWMF number 145/004, was scheduled for April 2017. METHODS: The guidelines were developed by 13 scientific societies and 2 patient self-help organizations coordinated by the German Pain Society. Working groups (n = 8) with a total of 42 members were formed balanced with respect to gender, medical expertise, position in the medical or scientific hierarchy and potential conflicts of interest. A search of the literature for case series (cross-sectional- and longitudinal studies) for the topics diagnosis, etiology and pathophysiology and for randomised controlled trials (RCT) for treatment modalities from December 2010 to May 2016 was performed in the Cochrane library, MEDLINE, PsycINFO and Scopus databases. Levels of evidence were assigned according to the classification system of the Oxford Centre for Evidence-Based Medicine version 2009. The strength of recommendations was achieved by multiple step formalized procedures to reach a consensus. Efficacy, risks, patient preferences and applicability of available therapies were weighed up against each other. The guidelines were reviewed and approved by the board of directors of the societies engaged in the development of the guidelines. RESULTS AND CONCLUSION: No consensus was achieved in the guideline group on whether the diagnostic label "juvenile fibromyalgia" should be used in the management of children and adolescents with chronic widespread pain. There was consensus in the guideline group that antidepressants and anticonvulsants should not be used to treat pain in the so-called juvenile fibromyalgia syndrome.
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Fibromialgia/diagnóstico , Fibromialgia/terapia , Manejo del Dolor/métodos , Guías de Práctica Clínica como Asunto , Adolescente , Niño , Terapia Combinada , Conferencias de Consenso como Asunto , Medicina Basada en la Evidencia , Fibromialgia/psicología , Alemania , Humanos , Manejo del Dolor/psicología , Prioridad del Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Sociedades Médicas , Resultado del TratamientoRESUMEN
background Research on body dysmorphic disorder (bdd) shows that many debates in the field of psychology, sociology and philosophy already focus on the ways 'ideals of the perfect body' influence this disorder. However, more work needs to be done on the question in what ways bdd is culturally, historically and technologically mediated. AIM: To argue that norms and values of the perfect body and the ways a society prescribes how body and mind should be related, are technologically mediated through different time frames, which influence disorders of disturbances of the body image. METHOD: Literature study. RESULTS: A cultural and historical comparison between the glass delusion and body dysmorphic disorder. CONCLUSION: It's impossible to state that the glass delusion and bdd are similar disorders regarding the types of patients or their symptoms. However, by comparing the relationships between the notion of a disturbed body image, and the technological mediation of cultural norms and values of the perfect body, both diseases in fact do have something in common.
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Trastorno Dismórfico Corporal/psicología , Imagen Corporal/psicología , Deluciones , Femenino , HumanosRESUMEN
Novel ground states might be realized in honeycomb lattices with strong spin-orbit coupling. Here we study the electronic structure of α-RuCl_{3}, in which the Ru ions are in a d^{5} configuration and form a honeycomb lattice, by angle-resolved photoemission, x-ray photoemission, and electron energy loss spectroscopy supported by density functional theory and multiplet calculations. We find that α-RuCl_{3} is a Mott insulator with significant spin-orbit coupling, whose low energy electronic structure is naturally mapped onto J_{eff} states. This makes α-RuCl_{3} a promising candidate for the realization of Kitaev physics. Relevant electronic parameters such as the Hubbard energy U, the crystal field splitting 10 Dq, and the charge transfer energy Δ are evaluated.
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Molecular dynamics simulations are employed to develop a theoretical model to predict the fluid-solid contact angle as a function of wall-sliding speed incorporating thermal fluctuations. A liquid bridge between counter-sliding walls is studied, with liquid-vapour interface-tracking, to explore the impact of wall-sliding speed on contact angle. The behaviour of the macroscopic contact angle varies linearly over a range of capillary numbers beyond which the liquid bridge pinches off, a behaviour supported by experimental results. Nonetheless, the liquid bridge provides an ideal test case to study molecular scale thermal fluctuations, which are shown to be well described by Gaussian distributions. A Langevin model for contact angle is parametrised to incorporate the mean, fluctuation and auto-correlations over a range of sliding speeds and temperatures. The resulting equations can be used as a proxy for the fully-detailed molecular dynamics simulation allowing them to be integrated within a continuum-scale solver.
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Comparatively few studies have been published describing Staphylococcus aureus/MRSA epidemiology in Central Asia including Pakistan. Here, we report the genotyping of Staphylococcus aureus strains (that include both methicillin-susceptible and methicillin-resistant Staphylococcus aureus) from community- and hospital-acquired skin and soft-tissue infections in a tertiary care hospital in the Malakand district of the Khyber Pakhtunkhwa Province of Pakistan. Forty-five isolates of Staphylococcus aureus were characterized by microarray hybridization. Twenty isolates (44 %) were MRSA, whereas 22 (49 %) were PVL-positive. Fourteen isolates (31 %) harboured both mecA and PVL genes. The dominant clones were CC121-MSSA (n = 15, 33 %) and the PVL-positive "Bengal Bay Clone" (ST772-MRSA-V; n = 13, 29 %). The PVL-positive CC8-MRSA-IV strain "USA300" was found once. The pandemic ST239-MRSA-III strain was absent, although it has previously been observed in Pakistan. These observations require a re-assessment of schemes for initial antibiotic therapy to cover MRSA and they emphasise the need for a rapid and non-molecular test for PVL.
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Infecciones de los Tejidos Blandos/microbiología , Infecciones Cutáneas Estafilocócicas/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/genética , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Exotoxinas/genética , Genotipo , Técnicas de Genotipaje , Humanos , Leucocidinas/genética , Análisis por Micromatrices , Epidemiología Molecular , Hibridación de Ácido Nucleico , Pakistán/epidemiología , Proteínas de Unión a las Penicilinas/genética , Infecciones de los Tejidos Blandos/epidemiología , Infecciones Cutáneas Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Centros de Atención TerciariaRESUMEN
Animal studies suggest that regular exposure to whole-body vibration (WBV) induces an anabolic response in bone and tendon. However, the effects of this type of intervention on human tendon properties and its influence on the muscle-tendon unit function have never been investigated. The aim of this study was to investigate the effect of WBV training on the patellar tendon mechanical, material and morphological properties, the quadriceps muscle architecture and the knee extension torque-angle relationship. Fifty-five subjects were randomized into either a vibration, an active control, or an inactive control group. The active control subjects performed isometric squats on a vibration platform without vibration. Muscle and tendon properties were measured using ultrasonography and dynamometry. Vibration training induced an increase in proximal (6.3%) and mean (3.8%) tendon cross-sectional area, without any appreciable change in tendon stiffness and modulus or in muscle architectural parameters. Isometric torque at a knee angle of 90° increased in active controls (6.7%) only and the torque-angle relation remained globally unchanged in all groups. The present protocol did not appreciably alter knee extension torque production or the musculo-tendinous parameters underpinning this function. Nonetheless, this study shows for the first time that WBV elicits tendon hypertrophy in humans.
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Ligamento Rotuliano/patología , Ligamento Rotuliano/fisiología , Acondicionamiento Físico Humano/métodos , Músculo Cuádriceps/fisiología , Vibración , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Hipertrofia/etiología , Articulación de la Rodilla/fisiología , Masculino , Fuerza Muscular , Ligamento Rotuliano/diagnóstico por imagen , Músculo Cuádriceps/anatomía & histología , Músculo Cuádriceps/diagnóstico por imagen , Torque , Ultrasonografía , Adulto JovenRESUMEN
PURPOSE: Reports about the immediate effects of whole body vibration (WBV) exposure upon torque production capacity are inconsistent. However, the changes in the torque-angle relationship observed by some authors after WBV may hinder the measurement of torque changes at a given angle. Acute changes in tendon mechanical properties do occur after certain types of exercise but this hypothesis has never been tested after a bout of WBV. The purpose of the present study was to investigate whether tendon compliance is altered immediately after WBV, effectively shifting the optimal angle of peak torque towards longer muscle length. METHODS: Twenty-eight subjects were randomly assigned to either a WBV (n = 14) or a squatting control group (n = 14). Patellar tendon CSA, stiffness and Young's modulus and knee extension torque-angle relationship were measured using ultrasonography and dynamometry 1 day before and directly after the intervention. Tendon CSA was additionally measured 24 h after the intervention to check for possible delayed onset of swelling. RESULTS: The vibration intervention had no effects on patellar tendon CSA, stiffness and Young's modulus or the torque-angle relationship. Peak torque was produced at ~70° knee angle in both groups at pre- and post-test. Additionally, the knee extension torque globally remained unaffected with the exception of a small (-6%) reduction in isometric torque at a joint angle of 60°. CONCLUSION: The present results indicate that a single bout of vibration exposure does not substantially alter patellar tendon properties or the torque-angle relationship of knee extensors.