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2.
Invest Ophthalmol Vis Sci ; 64(15): 20, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38099734

RESUMEN

Purpose: The purpose of this study was to examine the differences of optic nerve subarachnoid space (ONSAS) volume in patients with normal tension glaucoma (NTG) and healthy controls in different body positions. Methods: Eight patients with NTG and seven healthy controls underwent magnetic resonance imaging (MRI) examinations in head up tilt (HUT) +11 degrees and head down tilt (HDT) -5 degrees positions according to a randomized protocol determining the starting position. The ONSAS volume in both body positions was measured and compared between the two groups. The results were analyzed using a generalized linear model. Results: Between HDT and HUT, the postural ONSAS volume change was dependent on starting position (P < 0.001) and group (P = 0.003, NTG versus healthy). A subgroup analysis of those that were randomized to HUT examination first, coming directly from an upright position, showed that the patients with NTG had significantly larger positional ONSAS volume changes compared to the healthy controls; 121 ± 22 µL vs. 65 ± 37 µL (P = 0.049). Analysis of the ONSAS volume distribution showed different profiles for patients with NTG and healthy controls. Conclusions: There was a significant difference in ONSAS volume change between patients with NTG and healthy subjects when subjected to posture changes, specifically when going from upright to head-down posture. This indicates that patients with NTG had been exposed to a lower ONSAS pressure when they came from the upright posture, which suggests an increased translaminar pressure difference in upright position. This may support the theory that NTG has a dysfunction in an occlusion mechanism of the optic nerve sheath that could cause abnormally negative ONSAS pressures in upright posture.


Asunto(s)
Glaucoma de Baja Tensión , Humanos , Glaucoma de Baja Tensión/diagnóstico , Imagen por Resonancia Magnética , Postura , Nervio Óptico , Espacio Subaracnoideo/diagnóstico por imagen
3.
Sci Data ; 10(1): 251, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-37137931

RESUMEN

Variability in sea ice conditions, combined with strong couplings to the atmosphere and the ocean, lead to a broad range of complex sea ice dynamics. More in-situ measurements are needed to better identify the phenomena and mechanisms that govern sea ice growth, drift, and breakup. To this end, we have gathered a dataset of in-situ observations of sea ice drift and waves in ice. A total of 15 deployments were performed over a period of 5 years in both the Arctic and Antarctic, involving 72 instruments. These provide both GPS drift tracks, and measurements of waves in ice. The data can, in turn, be used for tuning sea ice drift models, investigating waves damping by sea ice, and helping calibrate other sea ice measurement techniques, such as satellite based observations.

4.
Psychopathology ; 56(6): 430-439, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36787718

RESUMEN

INTRODUCTION: The fear of scrutiny central in social anxiety disorder (SAD) points to a problem of the interpersonally perceivable body. Whereas the predominant cognitive-behavioral (CBT) account of the disorder understands this as a problem of excessive self-focused attention, the phenomenological literature reveals it as a sign of a fundamental transformation of body experience. The lived body absent from experience becomes the object body at the forefront of it. The present paper contributes to this literature by refining and grounding these notions in first-person descriptions of concrete experiences of social anxiety. METHOD: Repeated interviews were conducted with eight informants struggling with social anxiety and collected personal diaries. The interviews were informed by phenomenological concepts and a specific line of inquiry on body experiences. The analysis tested iteratively a set of phenomenologically grounded hypotheses of altered body experience against the first-person descriptions. RESULTS: A concept of bodily instrumentalization is developed which accounts for the tendency of self-directed attention and behavior central to the disorder. That is, the socially anxious patient experiences their body as entrapped by the Other and thus unable to act freely among them. This felt bodily self-enslavement for the Other shows itself in efforts to conceal the body from the others and to puppeteer it for them. DISCUSSION: The notion of bodily enslavement captures a central aspect of the suffering experienced by patients with SAD that exceeds the capability of the CBT language. Additionally, the social nature of the bodily instrumentalization that is constitutive of this suffering means that psychotherapy should not treat SAD as a cognitive disorder, but rather as an interpersonal disorder. Specifically, psychotherapy should offer patients shared interpersonal experiences in which they forget their bodily presence.


Asunto(s)
Fobia Social , Humanos , Fobia Social/psicología , Fobia Social/terapia , Trastornos de Ansiedad/psicología , Ansiedad/psicología , Miedo , Conducta Social
5.
Eur J Pain ; 26(4): 811-824, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35076138

RESUMEN

BACKGROUND: This exploratory study investigates if intra-articular injected gold microparticles in knee osteoarthritis (KOA) reduce immunomodulatory-based pain via proteomic changes in the synovial fluid (SF) and serum. METHODS: Thirty patients with moderate KOA were included. Intraarticular injections with 20 mg gold microparticles (72.000 particles, 20-40 µm in diameter) using the patient's synovial fluid (SF) as carrier were performed. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscores for pain, stiffness, and function were assessed at inclusion, 8 weeks and 2 years The PainDetect questionnaire, pain pressure threshold (PPT), temporal summation (TS), and conditioned pain modulation (CPM), and pain diary were assessed at inclusion and 8 weeks. Proteome analysis was performed on SF and blood samples before and after 8 weeks of treatment. RESULTS: A decrease in WOMAC scores (pain (p = 0.0001), stiffness (p = 0.0088), activity (p = 0.0001)), PainDetect (p = 0.0002) and increase in PPT (p = 0.001) and CPM (p = 0.021) and a decrease in TS (p = 0.03) were found after 8 weeks compared to inclusion assessments. At 2 years follow-up compared to baseline there was a decrease in WOMAC scores (pain (p = 0.0001), stiffness (p = 0.007), activity (p = 0.0001)) and PainDetect (p = 0.0001). In SF, 28 different proteins were downregulated and 11 upregulated (p < 0.05) mainly associated immune response. Similarly, 31 proteins were downregulated and 1 upregulated in serum (p < 0.05) reflecting key immune response and anatomical structure development processes. No adverse effects related to the treatment were recorded. CONCLUSIONS: Gold microparticles injected intra-articular in KOA joints may provide pain relief and an inflammatory modulatory effect based on proteome changes found in SF and serum. A randomized, controlled, double-blind study is needed to infer a conclusion. SIGNIFICANCE: This study indicates that intra-articular gold may provide advantages in clinical practice for managing knee osteoarthritic pain. The use of intraarticular gold can add new knowledge to the treatment of inflammation and pain.


Asunto(s)
Osteoartritis de la Rodilla , Método Doble Ciego , Oro/uso terapéutico , Humanos , Ácido Hialurónico/uso terapéutico , Inyecciones Intraarticulares , Articulación de la Rodilla , Proteómica , Resultado del Tratamiento
6.
Acta Ophthalmol ; 99(5): e679-e685, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33210819

RESUMEN

PURPOSE: To examine feasibility of phase-contrast magnetic resonance imaging (PCMRI) and to assess blood flow rate in the ophthalmic artery (OA) in patients with normal tension glaucoma (NTG) compared with healthy controls. METHODS: Sixteen patients with treated NTG and 16 age- and sex-matched healthy controls underwent PCMRI using a 3-Tesla scanner and ophthalmological examinations. OA blood flow rate was measured using a 2D PCMRI sequence with a spatial resolution of 0.35 mm2 . RESULTS: The blood flow rate in the NTG group was 9.6 ± 3.9 ml/min [mean ± SD] compared with 11.9 ± 4.8 ml/min in the control group. Resistance Index (RI) and Pulsatility Index (PI) were 0.73 ± 0.08 and 1.36 ± 0.29, respectively, in the NTG group and 0.68 ± 0.13 and 1.22 ± 0.40, respectively, in the healthy group. The mean visual field index (VFI) was 46% ± 25 for the worse NTG eyes. The measured differences observed between the NTG group and the control group in blood flow rate (p = 0.12), RI (p = 0.18) and PI (p = 0.27) were non-significant. CONCLUSIONS: This case-control study, using PCMRI, showed a slight, but non-significant, reduction in OA blood flow rate in the NTG patients compared with the healthy controls. These results indicate that blood flow may be of importance in the pathogenesis of NTG. Considering that only a limited portion of the total OA blood flow supplies the ocular system and the large inter-individual differences, a larger study or more advanced PCMRI technique might give the answer.


Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Presión Intraocular/fisiología , Glaucoma de Baja Tensión/fisiopatología , Imagen por Resonancia Magnética/métodos , Arteria Oftálmica/diagnóstico por imagen , Anciano , Estudios de Factibilidad , Femenino , Humanos , Glaucoma de Baja Tensión/diagnóstico , Masculino , Arteria Oftálmica/fisiopatología , Estudios Prospectivos , Curva ROC , Ultrasonografía Doppler en Color
7.
Nat Chem ; 9(8): 824-827, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28754940

RESUMEN

Structural DNA nanotechnology finds applications in numerous areas, but the construction of objects, 2D and 3D crystalline lattices and devices is prominent among them. Each of these components has been developed individually, and most of them have been combined in pairs. However, to date there are no reports of independent devices contained within 3D crystals. Here we report a three-state 3D device whereby we change the colour of the crystals by diffusing strands that contain dyes in or out of the crystals through the mother-liquor component of the system. Each colouring strand is designed to pair with an extended triangle strand by Watson-Crick base pairing. The arm that contains the dyes is quite flexible, but it is possible to establish the presence of the duplex proximal to the triangle by X-ray crystallography. We modelled the transition between the red and blue states through a simple kinetic model.


Asunto(s)
ADN/química , Nanotecnología/instrumentación , Carbocianinas/química , Color , ADN/genética , Hibridación de Ácido Nucleico , Transición de Fase
8.
Angew Chem Int Ed Engl ; 56(23): 6445-6448, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28466984

RESUMEN

A 3D array of organic semiconductors was assembled using a DNA scaffold. An octameric aniline molecule ("octaniline") was incorporated into a DNA building block based on a dimeric tensegrity triangle. The construct self-assembled to form a 3D crystal. Reversible redox conversion between the pernigraniline and leucoemeraldine states of the octaniline is retained in the crystal. Protonic doping gave emeraldine salt at pH 5, corresponding to the conductive form of polyaniline. Redox cycling within the crystal was visualized by color changes and Raman microscopy. The ease of conversion between the octaniline states suggests that it is a viable electronic switch within a unique 3D structure.

9.
Angew Chem Int Ed Engl ; 54(20): 5939-42, 2015 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-25810302

RESUMEN

DNA nanostructured tiles play an active role in their own self-assembly in the system described herein whereby they initiate a binding event that produces a cascading assembly process. We present DNA tiles that have a simple but powerful property: they respond to a binding event at one end of the tile by passing a signal across the tile to activate a binding site at the other end. This action allows sequential, virtually irreversible self-assembly of tiles and enables local communication during the self-assembly process. This localized signal-passing mechanism provides a new element of control for autonomous self-assembly of DNA nanostructures.


Asunto(s)
ADN/síntesis química , Nanoestructuras/química , ADN/química
10.
BMC Bioinformatics ; 14: 339, 2013 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-24266924

RESUMEN

BACKGROUND: Hidden Markov models are widely used for genome analysis as they combine ease of modelling with efficient analysis algorithms. Calculating the likelihood of a model using the forward algorithm has worst case time complexity linear in the length of the sequence and quadratic in the number of states in the model. For genome analysis, however, the length runs to millions or billions of observations, and when maximising the likelihood hundreds of evaluations are often needed. A time efficient forward algorithm is therefore a key ingredient in an efficient hidden Markov model library. RESULTS: We have built a software library for efficiently computing the likelihood of a hidden Markov model. The library exploits commonly occurring substrings in the input to reuse computations in the forward algorithm. In a pre-processing step our library identifies common substrings and builds a structure over the computations in the forward algorithm which can be reused. This analysis can be saved between uses of the library and is independent of concrete hidden Markov models so one preprocessing can be used to run a number of different models.Using this library, we achieve up to 78 times shorter wall-clock time for realistic whole-genome analyses with a real and reasonably complex hidden Markov model. In one particular case the analysis was performed in less than 8 minutes compared to 9.6 hours for the previously fastest library. CONCLUSIONS: We have implemented the preprocessing procedure and forward algorithm as a C++ library, zipHMM, with Python bindings for use in scripts. The library is available at http://birc.au.dk/software/ziphmm/.


Asunto(s)
Cadenas de Markov , Biblioteca de Péptidos , Programas Informáticos , Algoritmos , Animales , Simulación por Computador , Gorilla gorilla/genética , Humanos , Funciones de Verosimilitud , Estudios Observacionales como Asunto , Pan troglodytes/genética , Pongo/genética , Probabilidad , Factores de Tiempo
11.
FASEB J ; 25(2): 765-74, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20959516

RESUMEN

This study was undertaken to investigate the link between dietary fat content and intestinal levels of anorectic N-acylethanolamines (NAEs), including oleoylethanolamide (OEA), palmitoylethanolamide (PEA), and linoleoylethanolamide (LEA). Male rats were fed high-fat diets (HFDs) with variable percentages of fat [20-45% of total energy (E%)] for 1-7 d; afterward, the jejunums were isolated, and jejunal NAE levels were measured by liquid-chromatography mass spectrometry. Enzyme activities and mRNA expression levels were measured for two synthesizing enzymes, N-acylphosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and glycerophosphodiesterase (GDE1), and one degrading enzyme, fatty acid amide hydrolase (FAAH). We found a dose-response relation between the quantity/percentage of dietary fat, irrespective of the energy density, and the reduction of intestinal levels of OEA, PEA, and LEA. The reductions were present after 1 d of 45E% HFD. LEA, the major NAE species, was shown to have an anorectic potency slightly less than that of OEA but higher than PEA. Regulation at the enzyme level seems not to explain the changes in NAE levels. The results suggest the presence of a fat sensor, mediating the reduced intestinal NAE levels. The intestinal NAE levels are reduced in a dose- and time-dependent manner in response to dietary fat intake, and this may contribute to the well-known hyperphagic effect of HFDs.


Asunto(s)
Grasas de la Dieta/farmacología , Mucosa Intestinal/metabolismo , Intestinos/efectos de los fármacos , Lípidos/fisiología , Animales , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos , Regulación Enzimológica de la Expresión Génica/fisiología , Intestinos/enzimología , Ácidos Linoleicos/farmacología , Masculino , Alcamidas Poliinsaturadas/farmacología , ARN Mensajero , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
12.
J Org Chem ; 75(8): 2474-81, 2010 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-20329775

RESUMEN

A new DNA modifier containing triazene, ferrocene, and activated ester functionalities was synthesized and applied for electrochemical grafting and characterization of DNA at glassy carbon (GC) and gold electrodes. The modifier was synthesized from ferrocenecarboxylic acid by attaching a phenyltriazene derivative to one of the ferrocene Cp rings, while the other Cp ring containing the carboxylic acid was converted to an activated ester. The modifier was conjugated to an amine-modified DNA sequence. For immobilization of the conjugate at Au or GC electrodes, the triazene was activated by dimethyl sulfate for release of the diazonium salt. The salt was reductively converted to the aryl radical which was readily immobilized at the surface. DNA grafted onto electrodes exhibited remarkable hybridization properties, as detected through a reversible shift in the redox potential of the Fc redox label upon repeated hybridization/denaturation procedures with a complementary target DNA sequence. By using a methylene blue (MB) labeled target DNA sequence the hybridization could also be followed through the MB redox potential. Electrochemical studies demonstrated that grafting through the triazene modifier can successfully compete with existing protocols for DNA immobilization through the commonly used alkanethiol linkers and diazonium salts. Furthermore, the triazene modifier provides a practical one-step immobilization procedure.


Asunto(s)
Compuestos Ferrosos/química , Compuestos Ferrosos/síntesis química , Oligonucleótidos/química , Triazenos/química , Triazenos/síntesis química , Carbono/química , ADN/química , Electroquímica , Electrodos , Oro/química , Metalocenos , Modelos Moleculares , Conformación de Ácido Nucleico , Hibridación de Ácido Nucleico
13.
Int J Sport Nutr Exerc Metab ; 15(2): 195-210, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16089277

RESUMEN

The purpose of this study was to assess reasons for and prevalence of supplement use among varsity athletes and nonvarsity athlete students (controls) at a Canadian university. A questionnaire, distributed to 247 varsity athletes and 204 controls, included variables regarding sports participation, supplements used, reasons for usage, perceived effects, and areas of interest about supplements. Response rates were 85.5% among varsity athletes and 44.6% among controls. Supplements were used by 98.6% of varsity athletes and 94.3% of controls. Varsity men most often reported using sports drinks, and used these (and carbohydrate gels, protein powder, and creatine) more than varsity women. Caffeine products were most often reported by other groups. Health professionals and the Internet were the most reported information sources, while friends most often recommended supplements. Many subjects indicated knowing little about supplements and wanting to learn more. Results indicate a need for nutrition education among both varsity athletes and university students.


Asunto(s)
Suplementos Dietéticos/estadística & datos numéricos , Conductas Relacionadas con la Salud , Minerales/administración & dosificación , Deportes , Vitaminas/administración & dosificación , Adulto , Canadá , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Prevalencia , Encuestas y Cuestionarios , Universidades
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