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INTRODUCTION: For many years, surgeons and anesthetists have recognized that stress can be present in their daily professional practice. The goal of this study was to identify tools for assessing stress and cognitive load in the operating room. MATERIAL AND METHODS: We conducted a literature review in the PubMed database of scientific articles published on the subject without date limit using the keywords anesthesia, surgery, surgeon, cognitive workload, definition, pathophysiology, physiological measurement, objective, subjective, stress. RESULTS: Nineteen articles were selected, focusing on cardiac surgery, gastrointestinal surgery, vascular surgery and urology. No publications concerning ophthalmology were found through the literature search. The means of measurement found were either subjective, such as questionnaires, or objective, such as the study of heart rate variability (HRV), reaction time, eye movements, electrical conductivity of the skin, biological markers and electroencephalogram. Of all these measurement tools, the NASA-TLX questionnaire, used in four articles, and the HRV study, used in eight articles, appear to be the most widely used and are strongly correlated with stress. CONCLUSION: The articles reviewed use only some of the available tools for assessment of stress and cognitive load. The main objective is to improve the quality of care and the quality of life of caregivers. It would be interesting to develop other methods to identify and better characterize the risk factors that increase stress and cognitive load.
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Quirófanos , Cirujanos , Humanos , Calidad de Vida , Cirujanos/psicología , Cognición , AnestesistasRESUMEN
In this article, assistance to bone cement injection is studied, with a focus on vertebroplasty, a procedure dedicated to the treatment of vertebral compression fractures. A robotic system that can remotely be operated at pressures up to 140 bar is presented. It improves cement polymerization control, combining a cold passive exchanger that slows down the cement curing in the syringe and an active exchanger that controls the injected cement temperature. The cement remote injection uses a rate control teleoperation strategy with force feedback to help monitoring the cement state. In addition to laboratory assessments, cadaver experiments were performed to illustrate the satisfactory operation of the whole system.
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Fracturas por Compresión , Fracturas Osteoporóticas , Robótica , Fracturas de la Columna Vertebral , Cementos para Huesos , Humanos , Estudios Retrospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: A novel treatment has been developed for erythropoietic protoporphyria (EPP) (a rare condition that leaves patients highly sensitive to light). To fully understand the burden of EPP and the benefit of treatment, a novel patient reported outcome (PRO) measure was developed called the EPP-QoL. This report describes work to support the validation of this measure. METHODS: Secondary analysis of trial data was undertaken. These analyses explored the underlying factor structure of the measure. This supported the deletion of some items. Further work then explored the reliability of these factors, their construct validity and estimates of meaningful change. RESULTS: The factor analyses indicated that the items could be summarised in terms of two factors. One of these was labelled EPP Symptoms and the other EPP Wellbeing, based on the items included in the domain. EPP Symptoms had evidence to support its reliability and validity. EPP Wellbeing had poor psychometric properties. CONCLUSIONS: Based on the analysis it was recommended to drop the EPP Wellbeing domain (and associated items). EPP Symptoms, despite limitations in the development of items, showed evidence of validity. This work is consistent with the recommendations of a task force that provided recommendations regarding the development, modification and use of PROs in rare diseases.
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Income and education are both elements of a person's socioeconomic status, which is predictive of a broad range of life outcomes. The brain's gray matter volume (GMV) is influenced by socioeconomic status and mediators related to an unhealthy life style. We here investigated two independent general population samples comprising 2838 participants (all investigated with the same MRI-scanner) with regard to the association of indicators of the socioeconomic status and gray matter volume. Voxel-based morphometry without prior hypotheses revealed that years of education were positively associated with GMV in the anterior cingulate cortex and net-equivalent income with gray matter volume in the hippocampus/amygdala region. Analyses of possible mediators (alcohol, cigarettes, body mass index (BMI), stress) revealed that the relationship between income and GMV in the hippocampus/amygdala region was partly mediated by self-reported stressors, and the association of years of education with GMV in the anterior cingulate cortex by BMI. These results corrected for whole brain effects (and therefore not restricted to certain brain areas) do now offer possibilities for more detailed hypotheses-driven approaches.
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Amígdala del Cerebelo/anatomía & histología , Escolaridad , Sustancia Gris/anatomía & histología , Giro del Cíngulo/anatomía & histología , Hipocampo/anatomía & histología , Renta , Tamaño de los Órganos , Adulto , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/patología , Índice de Masa Corporal , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/patología , Estilo de Vida Saludable , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Clase Social , Estrés PsicológicoRESUMEN
The layout of an integrated millimetre-scale on-chip THz spectrometer is presented and its peformance demonstrated. The device is based on eight Schottky-diode detectors which are combined with narrowband THz antennas, thereby enabling the simultaneous detection of eight frequencies in the THz range on one chip. The size of the active detector area matches the focal spot size of superradiant THz radiation utilized in bunch compression monitors of modern linear electron accelerators. The 3â dB bandwidth of the on-chip Schottky-diode detectors is less than 10% of the center frequency and allows pulse-resolved detection at up to 5â GHz repetition rates. The performance of a first prototype device is demonstrated at a repetition rate of 100â kHz at the quasi-cw SRF linear accelerator ELBE operated with electron bunch charges between a few pC and 100â pC.
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BACKGROUND: Studies have demonstrated that statin therapy decreases the growth rate of abdominal aneurysms. However, the effect of statin therapy on the proximal aortic disease has not been sufficiently elucidated. AIM: We aimed to analyse the association between statin treatment and the severity of proximal aortopathy in patients with aortic valve disease. DESIGN: Cross-sectional study. METHODS: We prospectively identified 458 patients who were referred for aortic valve surgery from 2008 to 2014. Pre-operative measurement of the proximal aorta was performed by TEE, CT or MRT scan. Data of dyslipidemia treatment was obtained by questionnaire. RESULTS: The mean ascending aortic diameter in the whole study population was comparable in patients with vs. without statin therapy (i.e. 42.7 mm vs. 43.6 mm, P = 0.46). Logistic regression analysis showed no significant association between statin therapy and proximal aortopathy ≥ 40 mm in the whole study group (OR = 0.69, P = 0.10). For the BAV sub-group, HDL (OR = 0.54, P = 0.038) and cholesterol levels (OR = 2.00, P = 0.038) were found significantly associated with the proximal aortic disease. In the BAV cohort, the statin users with target HDL levels presented a significantly smaller proximal aortic diameter (40.1 mm vs. 46 mm, P = 0.02). CONCLUSION: Pre-operative statin therapy demonstrated no significant association with the expression of proximal aortopathy. However, more than 40% of the statin users presented uncontrolled lipid levels at the time of the study. In the BAV sub-group, the statins users with target HDL levels showed a significantly smaller ascending aorta diameter. Target HDL and cholesterol levels were strongly associated with proximal aortic dilation in BAV patients.
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Cardiopatías Congénitas/tratamiento farmacológico , Enfermedades de las Válvulas Cardíacas/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Lípidos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de la Aorta/complicaciones , Válvula Aórtica/diagnóstico por imagen , Enfermedad de la Válvula Aórtica Bicúspide , Estudios Transversales , Femenino , Cardiopatías Congénitas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Cuidados Preoperatorios , Estudios Prospectivos , Índice de Severidad de la EnfermedadRESUMEN
The energy deposition of ions in dense plasmas is a key process in inertial confinement fusion that determines the α-particle heating expected to trigger a burn wave in the hydrogen pellet and resulting in high thermonuclear gain. However, measurements of ion stopping in plasmas are scarce and mostly restricted to high ion velocities where theory agrees with the data. Here, we report experimental data at low projectile velocities near the Bragg peak, where the stopping force reaches its maximum. This parameter range features the largest theoretical uncertainties and conclusive data are missing until today. The precision of our measurements, combined with a reliable knowledge of the plasma parameters, allows to disprove several standard models for the stopping power for beam velocities typically encountered in inertial fusion. On the other hand, our data support theories that include a detailed treatment of strong ion-electron collisions.
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Many Cryptosporidium species/genotypes are not considered infectious to humans, and more realistic estimations of seasonal infection risks could be made using human infectious species/genotype information to inform quantitative microbial risk assessments (QMRA). Cryptosporidium oocyst concentration and species/genotype data were collected from three surface water surveillance programs in two river basins [South Nation River, SN (2004-09) and Grand River, GR (2005-13)] in Ontario, Canada to evaluate seasonal infection risks. Main river stems, tributaries, agricultural drainage streams, water treatment plant intakes, and waste water treatment plant effluent impacted sites were sampled. The QMRA employed two sets of exposure data to compute risk: one assuming all observed oocysts were infectious to humans, and the other based on the fraction of oocysts that were C. hominis and/or C. parvum (dominant human infectious forms of the parasite). Viability was not considered and relative infection risk was evaluated using a single hypothetical recreational exposure. Many sample site groupings for both river systems, had significant seasonality in Cryptosporidium occurrence and concentrations (p ≤ 0.05); occurrence and concentrations were generally highest in autumn for SN, and autumn and summer for GR. Mean risk values (probability of infection per exposure) for all sites combined, for each river system, were roughly an order of magnitude lower (avg. of SN and GR 5.3 × 10-5) when considering just C. parvum and C. hominis oocysts, in relation to mean infection risk (per exposure) assuming all oocysts were infectious to humans (5.5 × 10-4). Seasonality in mean risk (targeted human infectious oocysts only) was most strongly evident in SN (e.g., 7.9 × 10-6 in spring and 8.1 × 10-5 in summer). Such differences are important if QMRA is used to quantify effects of water safety/quality management practices where inputs from a vast array of fecal pollution sources can readily occur. Cryptosporidium seasonality in water appears to match the seasonality of human infections from Cryptosporidium in the study regions. This study highlights the importance of Cryptosporidium species/genotype data to help determine surface water pollution sources and seasonality, as well as to help more accurately quantify human infection risks by the parasite.
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Cryptosporidium/genética , Estaciones del Año , Animales , Criptosporidiosis/epidemiología , Genotipo , Humanos , OocistosRESUMEN
We report on the experimental characterisation of laser-driven ion beams using a Thomson Parabola Spectrometer (TPS) equipped with trapezoidally shaped electric plates, proposed by Gwynne et al. [Rev. Sci. Instrum. 85, 033304 (2014)]. While a pair of extended (30 cm long) electric plates was able to produce a significant increase in the separation between neighbouring ion species at high energies, deploying a trapezoidal design circumvented the spectral clipping at the low energy end of the ion spectra. The shape of the electric plate was chosen carefully considering, for the given spectrometer configuration, the range of detectable ion energies and species. Analytical tracing of the ion parabolas matches closely with the experimental data, which suggests a minimal effect of fringe fields on the escaping ions close to the wedged edge of the electrode. The analytical formulae were derived considering the relativistic correction required for the high energy ions to be characterised using such spectrometer.
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Loss of HOXA5 expression occurs frequently in breast cancer and correlates with higher pathological grade and poorer disease outcome. However, how HOX proteins drive differentiation in mammalian cells is poorly understood. In this paper, we investigated cellular and molecular consequences of loss of HOXA5 in breast cancer, and the role played by retinoic acid in HOXA5 function. Analysis of global gene expression data from HOXA5-depleted MCF10A breast epithelial cells, followed by validation, pointed to a role for HOXA5 in maintaining several molecular traits typical of the epithelial lineage such as cell-cell adhesion, tight junctions and markers of differentiation. Depleting HOXA5 in immortalized MCF10A or transformed MCF10A-Kras cells reduced their CD24+/CD44lo population, enhanced self-renewal capacity and reduced expression of E-cadherin (CDH1) and CD24. In the case of MCF10A-Kras, HOXA5 loss increased branching and protrusive morphology in Matrigel, all features suggestive of epithelial to basal transition. Further, orthotopically implanted xenografts of MCF10A-Kras-scr grew as well-differentiated pseudo-luminal carcinomas, while MCF10A-Kras-shHOXA5 cells formed aggressive, poorly differentiated carcinomas. Conversely, ectopic expression of HOXA5 in aggressive SUM149 or SUM159 breast cancer cells reversed the cellular and molecular alterations observed in the HOXA5-depleted cells. Retinoic acid is a known upstream regulator of HOXA5 expression. HOXA5 depletion in MCF10A cells engineered to express doxycycline-induced shHOXA5 slowed transition of cells from a less differentiated CD24-/CD44+ to the more differentiated CD24+/CD44+ state. This transition was promoted by retinal treatment, which upregulated endogenous HOXA5 expression and caused re-expression of occludin and claudin-7 (CLDN7). Expression of CDH1 and CD24 was transcriptionally upregulated by direct binding of HOXA5 to their promoter sequences as demonstrated by luciferase and ChIP analyses. Thus, loss of HOXA5 in mammary cells leads to loss of epithelial traits, an increase in stemness and cell plasticity, and the acquisition of more aggressive phenotypes.
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Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Antígeno CD24/genética , Cadherinas/genética , Transformación Celular Neoplásica/genética , Regulación Neoplásica de la Expresión Génica , Proteínas de Homeodominio/genética , Animales , Antígenos CD , Cadherinas/metabolismo , Adhesión Celular , Línea Celular Tumoral , Autorrenovación de las Células/genética , Análisis por Conglomerados , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal/genética , Femenino , Perfilación de la Expresión Génica , Xenoinjertos , Proteínas de Homeodominio/metabolismo , Humanos , Ratones , Clasificación del Tumor , Regiones Promotoras Genéticas , Unión Proteica , Células Madre/metabolismoRESUMEN
The porphyrias comprise a clinically, biochemically, and genetically heterogeneous group of predominantly hereditary metabolic disorders resulting from a dysfunction along the heme biosynthetic pathway. Whereas most variants can manifest with different cutaneous symptoms, some types only reveal life-threatening acute neurovisceral attacks. Therefore, interdisciplinary care of these patients is advisable. In this article, we provide an overview of characteristic clinical and laboratory findings in the various forms of porphyria and a diagnostic algorithm.
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Ácido Aminolevulínico/orina , Porfirias/diagnóstico , Protoporfirinas/orina , Enfermedades de la Piel/diagnóstico , Biomarcadores/sangre , Diagnóstico Diferencial , Porfirias/orina , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Enfermedades de la Piel/orinaRESUMEN
BACKGROUND: Erythropoietic protoporphyria, the second most common type of the cutaneous porphyrias, is due to an enzymatic deficiency of ferrochelatase, the last enzyme in heme biosynthesis. The enzyme defect leads to an accumulation of protoporphyrin IX in erythrocytes and an elevated excretion of this metabolite in the feces. CLINICAL PRESENTATION: Usually, disease onset is in early infancy, characterized by increased photosensitivity. During or shortly after sunlight exposure, affected individuals suffer from burning, stinging, itching, and pain in sun-exposed skin areas. These symptoms lead to a considerably reduced quality of life and strict avoidance of sunlight exposure. Subacute symptoms include visible changes like edema and erythema. In the further course of the disease, chronic signs such as lichenification and scarring may occur. A severe complication of hepatic protoporphyrin IX accumulation is the development of a potentially life-threatening fulminant liver failure. Therefore, hepatic laboratory tests and ultrasound of the liver should be performed regularly. THERAPY: Traditionally, therapy merely consisted of consequent photoprotection and orally administered ß-carotene. A novel treatment option is afamelanotide (Scenesse®), a synthetic analogue of the naturally occurring α-melanocyte stimulating hormone. Afamelanotide, administered as a subcutaneous implant, induces eumelanin production, independent of preceding UV light exposure. This may enable patients with erythropoietic protoporphyria to stay in sunlight significantly longer than previously possible without complaints, thus, substantially improving quality of life.
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Porfiria Eritropoyética/diagnóstico , Porfiria Eritropoyética/terapia , Protoporfirinas/análisis , alfa-MSH/análogos & derivados , beta Caroteno/administración & dosificación , Administración Oral , Biomarcadores/análisis , Diagnóstico Diferencial , Medicina Basada en la Evidencia , Heces/química , Humanos , Porfiria Eritropoyética/diagnóstico por imagen , Evaluación de Síntomas/métodos , Resultado del Tratamiento , Ultrasonografía/métodos , alfa-MSH/administración & dosificaciónRESUMEN
BACKGROUND: Congenital erythropoetic porphria is a very rare type of autosomal recessive nonacute porphyria. Homozygous or compound heterozygous mutations in the uroporphyrinogen III consynthase gene cause a marked enzymatic deficiency of uroporphyrinogen III consynthase, the fourth enzyme along the heme biosynthetic pathway. CLINICAL PRESENTATION: Clinically, affected patients are characterized by a moderate to severe photosensitivity. Starting early in infancy, they develop blisters, erosions, and exulcerations in sun-exposed areas of the body, often resulting in scar formation and mutilation. Besides the cutaneous changes, hemolytic anemia, transfusion-dependent pancytopenia, hepatosplenomegaly and liver cirrhosis can occur. Due to increased susceptibility for infections and because of the hematological and hepatic complications, affected individuals have a decreased life expectancy, rarely exceeding 40 years of age. TREATMENT: Currently, no causal treatment is available for the disorder. Therefore, the most important therapeutic modality is strict avoidance of sunlight, preferably by inversion of the day-night rhythm, or at least consequent photoprotection with adequate clothing. In severe cases, bone marrow or stem cell transplantation should be considered.
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Porfiria Eritropoyética/diagnóstico , Porfiria Eritropoyética/terapia , Protección Radiológica/métodos , Protectores Solares/uso terapéutico , Medicina Basada en la Evidencia , Humanos , Porfiria Eritropoyética/epidemiología , Prevalencia , Factores de Riesgo , Luz Solar , Resultado del TratamientoRESUMEN
AIMS: To assess the removal of viruses through the multiple steps of wastewater treatment in a full-scale municipal wastewater treatment plant in Alberta, Canada. METHODS AND RESULTS: Samples were collected after each of the five treatment steps for a period of 16 months. The amount of viruses and their infectivity were analysed using real-time quantitative PCR (qPCR) and integrated viral cell culture (ICC), respectively. Bacterial indicator Escherichia coli was also tested using membrane filtration. Seven viruses including Norovirus (NoV), Rotavirus (RV), Sapovirus (SaV), Astrovirus (AsV), Adenovirus (AdV), Enterovirus (EV) and JC virus (JCV) were detected in 16 primary effluents in which infectious viruses were present. Different treatment steps showed various efficiencies in virus removal, with membrane ultrafiltration as the most effective at 4·6-7·0 log reduction. CONCLUSIONS: We observed high prevalence of viruses in raw wastewater and different viral reduction after various treatment steps. The discharge of treated wastewater with infectious viruses represents potential risks to human, animal and environmental health. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a comprehensive assessment of the removal of NoV, RV, SaV, AsV, AdV, EV, JCV and Reovirus from wastewater by current procedures of municipal wastewater treatment and discusses the applicability of various viruses as viral indicators for water quality.
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Virus , Aguas Residuales/microbiología , Purificación del Agua , Alberta , Humanos , Virosis/virología , Virus/clasificación , Virus/genética , Virus/aislamiento & purificaciónRESUMEN
Giardia spp. is a common gastrointestinal (GI) parasite of multiple host species, including dogs and humans, with the potential for zoonotic transmission. The risk of GI parasitism in dogs (including Giardia spp.) may increase with park use in urban areas. This study aimed to (1) determine whether park attendance is a risk factor for Giardia spp. infection in dogs and (2) characterize the behavioural and demographic risk factors for Giardia spp. infection in park-attending and non-park-attending dogs. From August to September 2012, a total of 1293 dog owners completed a survey and 860 corresponding dog faecal samples were collected. Dog faeces were screened for Giardia spp. using a direct immunofluorescence assay and associations assessed among behaviours, demographics, and Giardia spp. infection. Main results included off-leash and swimming frequencies within parks as significantly positively associated with Giardia spp. infection in dogs. Dog-owner age was negatively associated with off-leash and swimming frequencies in parks. The results suggest some recreational behaviours in parks and certain demographics are risk factors for parasitism in pet dogs.
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Ciudades , Giardiasis/veterinaria , Parques Recreativos/estadística & datos numéricos , Mascotas , Natación/estadística & datos numéricos , Adolescente , Adulto , Alberta , Animales , Estudios Transversales , Enfermedades de los Perros/epidemiología , Perros , Heces/parasitología , Femenino , Giardiasis/epidemiología , Giardiasis/transmisión , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto JovenRESUMEN
AIMS: To utilize comparative accessory gene fingerprinting to discriminate between naturalized and faecal Escherichia coli, with particular emphasis on strains from phylogroup B1. METHODS AND RESULTS: Fourteen accessory genes that were potentially ecotype-specific were selected on the basis of comparative genomic DNA sequence analysis between faecal and environmental strains and also using a literature-based strategy. PCR assays were designed for each gene, and used to screen 107 faecal strains from various hosts and 106 environmental strains from surface water and sediment. While none of the 14 accessory genes were ecotype-specific, six of the genes were ecotype-enriched. Specifically, toxin-antitoxin system genes were more abundant among faecal strains, whereas genes involved in iron acquisition, complement resistance/surface exclusion, and biofilm formation were more abundant among environmental strains. These six genes were used to form composite fingerprints which revealed the presence of several ecotype-specific and -enriched fingerprints. Notably, some of the environmental strain-specific or -enriched fingerprints consisted of strains putatively belonging to clade ET-1, which has been previously recognized as a naturalized subpopulation. CONCLUSIONS: Unlike single genes which did not reliably distinguish between faecal and naturalized phylogroup B1 E. coli strains, composite fingerprints of ecotype-enriched accessory genes may offer a novel method for distinguishing between these two populations. SIGNIFICANCE AND IMPACT OF THE STUDY: Accessory gene fingerprinting may have important practical implications for improving the specificity of methods that are widely used for quantifying and identifying the sources of faecal contamination in surface water.
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Técnicas de Tipificación Bacteriana/métodos , Dermatoglifia del ADN/métodos , Proteínas de Escherichia coli/genética , Escherichia coli/clasificación , Escherichia coli/genética , Agua Dulce/microbiología , Escherichia coli/aislamiento & purificación , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Heces/microbiología , Humanos , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la PolimerasaRESUMEN
BACKGROUND: Broadband ultraviolet B (BB-UVB) is a well-established treatment option in dermatology. However, during the last decade BB-UVB has increasingly been replaced by narrowband UVB 311 nm (NB-UVB), especially in the therapy of psoriasis, atopic eczema and vitiligo. Several studies have indicated a better therapeutic response for almost all indications compared with BB-UVB. OBJECTIVES: The aim of our study was to investigate the phototoxic effects of NB-UVB in comparison with BB-UVB in vivo. METHODS: Therefore, we employed the photo hen's egg test (PHET), an established phototoxic model, based on the yolk sac blood vessel system of incubated hen's eggs. NB-UVB and BB-UVB dosages increasing from 30 up to 1200 mJ cm(-2) were applied on 17 test groups (each n = 12 eggs) and two unirradiated test groups served as controls. Twenty-four hours after irradiation we observed the following test parameters: lethality, membrane discoloration and haemorrhages. RESULTS: Following our results, the lethal half dose (LD50) was 60 and 720 mJ cm(-2) for BB-UVB and NB-UVB, respectively. These LD50 dosages provoked severe membrane discoloration and haemorrhaging. Summarizing our results, the LD50 of NB-UVB was 12-fold higher than BB-UVB. CONCLUSIONS: Interestingly, these findings are in good accordance with the literature, where the minimal erythema dose (MED) of NB-UVB in human skin is up to 14 times higher than the MED of BB-UVB. These results show that the PHET is a valid test model to evaluate the phototoxic effects of various UVB wavelengths. Moreover, our results indicate that regarding the investigation of phototoxic effects the PHET might serve as a model representative for human skin, which might reduce the extent of photoprovocation in humans in the future.
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Rayos Ultravioleta/efectos adversos , Cigoto/efectos de la radiación , Animales , Vasos Sanguíneos/efectos de la radiación , Embrión de Pollo , Pollos , Método Doble Ciego , Hemorragia/etiología , Radiografía , Saco Vitelino/diagnóstico por imagenRESUMEN
Helium shows fascinating quantum phenomena unseen in any other element. In its liquid phase, it is the only known superfluid. The smallest aggregates of helium, the dimer (He2) and the trimer (He3) are, in their predicted structure, unique natural quantum objects. While one might intuitively expect the structure of (4)He3 to be an equilateral triangle, a manifold of predictions on its shape have yielded an ongoing dispute for more than 20 years. These predictions range from (4)He3 being mainly linear to being mainly an equilateral triangle. Here we show experimental images of the wave functions of (4)He3 and (3)He(4)He2 obtained by Coulomb explosion imaging of mass-selected clusters. We propose that (4)He3 is a structureless random cloud and that (3)He(4)He2 exists as a quantum halo state.
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The aim of the present study was to explore brain activities associated with creativity and expertise in literary writing. Using functional magnetic resonance imaging (fMRI), we applied a real-life neuroscientific setting that consisted of different writing phases (brainstorming and creative writing; reading and copying as control conditions) to well-selected expert writers and to an inexperienced control group. During creative writing, experts showed cerebral activation in a predominantly left-hemispheric fronto-parieto-temporal network. When compared to inexperienced writers, experts showed increased left caudate nucleus and left dorsolateral and superior medial prefrontal cortex activation. In contrast, less experienced participants recruited increasingly bilateral visual areas. During creative writing activation in the right cuneus showed positive association with the creativity index in expert writers. High experience in creative writing seems to be associated with a network of prefrontal (mPFC and DLPFC) and basal ganglia (caudate) activation. In addition, our findings suggest that high verbal creativity specific to literary writing increases activation in the right cuneus associated with increased resources obtained for reading processes.