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1.
Phys Rev Lett ; 133(2): 023002, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39073978

RESUMEN

We demonstrate a new temperature record for image-current mediated sympathetic cooling of a single proton in a cryogenic Penning trap by laser-cooled ^{9}Be^{+}. An axial mode temperature of 170 mK is reached, which is a 15-fold improvement compared to the previous best value. Our cooling technique is applicable to any charged particle, so that the measurements presented here constitute a milestone toward the next generation of high-precision Penning-trap measurements with exotic particles.

2.
Phys Rev Lett ; 133(5): 053201, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39159098

RESUMEN

We demonstrate efficient subthermal cooling of the modified cyclotron mode of a single trapped antiproton and reach particle temperatures T_{+}=E_{+}/k_{B} below 200 mK in preparation times shorter than 500 s. This corresponds to the fastest resistive single-particle cyclotron cooling to subthermal temperatures ever demonstrated. By cooling trapped particles to such low energies, we demonstrate the detection of antiproton spin transitions with an error rate <0.000 023, more than 3 orders of magnitude better than in previous best experiments. This method has enormous impact on multi-Penning-trap experiments that measure magnetic moments with single nuclear spins for tests of matter and antimatter symmetry, high-precision mass spectrometry, and measurements of electron g factors bound to highly charged ions that test quantum electrodynamics and establish standards for magnetometry.

3.
Osteoporos Int ; 33(4): 881-887, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34775527

RESUMEN

Low adherence for denosumab (Dmab, Prolia®) is of major concern. Dutch pharmacies deliveries were calculated recently being 76.5% for a total of 3 injections. INTRODUCTION: Comparing a model where the prescriber maintains responsibility for adherence (model HC1) (Dmab is purchased and dispensed by patient's own community pharmacy and administered through a home care service (HC)) or an all-in-one model where the pharmacist maintains responsibility for the adherence (Dmab is purchased, dispensed, and administered by a pharmacist's HC) (HC2). METHODS: We counted the number of Dmab injections, follow-up appointments on time, Dmab administrations delayed to a maximum of 60 days, the number of Dmab discontinuations, and all causes legally traceable under EU privacy act (EDPR). RESULTS: Home care started by 2014 (study closure in 2021) and included 711 Dmab injections to 256 unique patients: HC1: 536 and HC2: 175 orders. The whole group received on average 2.8 Dmab injections by consistent intervals of about 182 days. Average administration after the latest Dmab injection: 272.8 days (HC1: 362.0 and HC2: 124.0 days). Administration of a subsequent injection > 60 days occurred in 26.6% (HC1: 38.8% and HC2: 6.2%; OR = 9.49). After adjustment for no more than three Dmab injections administered per patient, it occurred in 27.3% (HC1: 51.8% and HC2 4.4%; OR = 23.34). CONCLUSION: It was possible to achieve 94% adherence for Dmab injections treatment just by transferring the complete supply chain to one pharmacy-initiated home care provider after treatment initiation by either a physician or FLS health care professional.


Asunto(s)
Conservadores de la Densidad Ósea , Servicios de Atención de Salud a Domicilio , Farmacias , Farmacia , Conservadores de la Densidad Ósea/uso terapéutico , Denosumab/uso terapéutico , Humanos
4.
Osteoporos Int ; 31(10): 2007-2015, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32405912

RESUMEN

This study aimed to gain insight in specific characteristics and beliefs of FLS non-responders. INTRODUCTION: The proportion of non-responding fracture liaison service (FLS) invitees is high but characteristics of FLS non-responders are unknown. METHODS: We contacted FLS non-responders by telephone to consent with home visit (HV) and to fill in a questionnaire or, if HV was refused, to receive a questionnaire by post (Q), to gain insight in beliefs on fracture cause and subsequent fracture risk. RESULTS: Out of 716 FLS invitees, 510 attended, nine declined, and 197 did not respond. Of these non-responders, 181 patients were consecutively traced and phoned until 50 consented with HV. Forty-two declined HV but consented with Q. Excluded were eight Q-consenters in whom no choice was offered (either HV or Q) and 81 patients who declined any proposition (non-HV|Q). 62% HV and Q could recall the FLS invitation letter. The fracture cause was differently believed between HV and Q; the fall (96% versus 79%, p = .02), bad physical condition (36% versus 2%, p = .0001), dizziness or imbalance (24% versus Q 7%, p = .03), osteoporosis (16% versus 2%, p = .02), and increased fracture risk (26% versus 17%, NS). Age ≥ 70, woman, and major fracture were significantly associated with HV consent compared to Q (OR 2.7, 2.5, and 2.4, respectively) and HV compared to non-HV|Q (OR 16.8, 5.3, and 6.1). CONCLUSION: FLS non-responders consider fracture risk as low. Note, 50 patients (about 25%) consented with a home visit after one telephone call, mainly older women with a major fracture. This non-responder subgroup with high subsequent fracture risk is therefore approachable for secondary fracture prevention.


Asunto(s)
Visita Domiciliaria , Osteoporosis , Fracturas Osteoporóticas , Anciano , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Humanos , Fracturas Osteoporóticas/prevención & control , Prevención Secundaria , Encuestas y Cuestionarios
5.
Neurochem Res ; 45(6): 1375-1386, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31754956

RESUMEN

The cystine/glutamate antiporter system Xc- (SXc-) mediates the exchange of intracellular L-glutamate (L-Glu) with extracellular L-cystine (L-Cys2). Both the import of L-Cys2 and the export of L-Glu take on added significance in CNS cells, especially astrocytes. When the relative activity of SXc- overwhelms the regulatory capacity of the EAATs, the efflux of L-Glu through the antiporter can be significant enough to trigger excitotoxic pathology, as is thought to occur in glioblastoma. This has prompted considerable interest in the pharmacological specificity of SXc- and the development of inhibitors. The present study explores a series of analogues that are structurally related to sulfasalazine, a widely employed inhibitor of SXc-. We identify a number of novel aryl-substituted amino-naphthylsulfonate analogues that inhibit SXc- more potently than sulfasalazine. Interestingly, the inhibitors switch from a competitive to noncompetitive mechanism with increased length and lipophilic substitutions, a structure-activity relationship that was previously observed with aryl-substituted isoxazole. These results suggest that the two classes of inhibitors may interact with some of the same domains on the antiporter protein and that the substrate and inhibitor binding sites may be in close proximity to one another. Molecular modeling is used to explore this possibility.


Asunto(s)
Sistema de Transporte de Aminoácidos y+/antagonistas & inhibidores , Sistema de Transporte de Aminoácidos y+/metabolismo , Sulfasalazina/análogos & derivados , Sulfasalazina/farmacología , Sistema de Transporte de Aminoácidos y+/química , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/metabolismo , Antiinflamatorios no Esteroideos/farmacología , Antiportadores/antagonistas & inhibidores , Antiportadores/química , Antiportadores/metabolismo , Sitios de Unión/efectos de los fármacos , Sitios de Unión/fisiología , Línea Celular Tumoral , Humanos , Simulación del Acoplamiento Molecular/métodos , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Sulfasalazina/metabolismo
6.
Osteoporos Int ; 30(8): 1597-1606, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31129686

RESUMEN

This questionnaire-based study evaluated the reasons for attendance or non-attendance at the fracture liaison service in patients with a recent fracture. Frailty, male sex, living alone, and low education were associated with non-attendance, and the information perceived by the patient was associated with attendance. INTRODUCTION: The purpose of this study was to evaluate hospital registration- and patient-related factors associated with attendance or non-attendance to the Fracture Liaison Service (FLS). METHODS: Out of 1728 consecutive patients registered with a recent fracture at hospital entry, and after exclusion of 440 patients because of death, residence in a nursing home, already on osteoporosis treatment, or recent DXA, 1288 received an FLS invitation. We evaluated the hospital registration of fractures at entry and exit of the hospital. A questionnaire was sent to all invited patients to evaluate factors related to non-attendance (including age, gender, frailty, living alone, income, education, extrinsic motivations (impact of perceived information) and intrinsic motivations (patient's own perceived views and opinions) and to attendance (personal impact of clinical professionals' advice). RESULTS: There were 278 more hospital exit codes than entry codes. Of the 1288 invited patients, 745 returned analyzable questionnaires (537 attenders and 208 non-attenders). Non-attendance was associated with male gender (OR: 2.08, 95% CI: 1.35, 3.21), frailty (OR: 1.62, CI: 1.08, 2.45), living alone (OR:2.05, CI: 1.48, 2.85), low education (OR: 1.82, CI: 1.27, 2.63), not interested in bone strength (OR: 1.85, CI: 1.33, 2.63), and being unaware of increased subsequent fracture risk (OR: 1.75, CI: 1.08, 2.86). Information perceived by the patient was significantly associated with attendance (OR: 3.32, CI: 1.75, 6.27). CONCLUSION: Fracture entry registration inaccuracies, male gender, frailty, living alone, having low general education, or low interest in bone health and subsequent fracture risk were independently associated with FLS non-attendance. Adequately perceived advice (to have a bone densitometry and attend the FLS) was strongly associated with FLS attendance.


Asunto(s)
Motivación , Fracturas Osteoporóticas/prevención & control , Aceptación de la Atención de Salud/estadística & datos numéricos , Factores de Edad , Anciano , Femenino , Fragilidad/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/psicología , Sistema de Registros , Prevención Secundaria/métodos , Factores Sexuales , Factores Socioeconómicos , Encuestas y Cuestionarios
7.
Osteoporos Int ; 29(4): 813-824, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29260291

RESUMEN

Telephone call intervention did not improve alendronate persistence in Fracture Liaison Service (FLS) patients in this study. A bone turnover marker cut-off point for alendronate persistence is proposed for individual FLS patients. INTRODUCTION: FLS aims to prevent subsequent fractures, which should include improving patients' persistence with prescribed oral bisphosphonates. We studied the influence of telephone calls and the predictive value of changes in bone turnover markers (BTMs) for evaluating persistence with alendronate. METHODS: Postmenopausal women with a recent fracture and osteoporosis who started alendronate were randomized to receive three phone calls (PC) (after 1, 4, and 12 months) or no phone calls (no PC). s-CTX and P1NP were measured at baseline and after 3, 6, 9, and 12 months. As a reference group, 30 postmenopausal osteopenic patients with a recent fracture were analyzed as well. Persistence was assessed using the Dutch National Switch Point Pharmacies-GPs database and cross-referenced with PC, no PC, and BTM changes. Cut-off values of BTMs were calculated based on least significant change (LSC) and also on underrunning median values of the untreated osteopenic postmenopausal reference group with a recent fracture. RESULTS: Out of 119 patients, 93 (78%) completed 12 months follow-up (45 PC and 48 no PC). Mean age was 69 years. Persistence was similar in PC and no PC participants. The cut-off value > 29% (< 415 ng/L) as LSC of s-CTX and > 36% (< 53.1 µg/L) as LSC of P1NP was determined optimally showing alendronate persistence after 1 year (being 93 and 88%, respectively). CONCLUSIONS: In this context, telephone calls did not improve persistence. In around 90% of patients, 1-year alendronate persistence was confirmed by achieving LSC of s-CTX and of P1NP at 12 months.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Monitoreo de Drogas/métodos , Cumplimiento de la Medicación/estadística & datos numéricos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/prevención & control , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/farmacología , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/fisiología , Difosfonatos/administración & dosificación , Difosfonatos/farmacología , Femenino , Humanos , Persona de Mediana Edad , Países Bajos , Osteoporosis Posmenopáusica/fisiopatología , Teléfono
8.
Eur J Neurol ; 25(10): 1290-1298, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29904974

RESUMEN

BACKGROUND AND PURPOSE: Antibodies to glycine receptors (GlyR-Abs) were first defined in progressive encephalopathy with rigidity and myoclonus (PERM) but were subsequently identified in other clinical presentations. Our aim was to assess the clinical associations of all patients identified with GlyR-Abs in Queensland, Australia, between April 2014 and May 2017 and to compare these to cases reported in the literature. METHODS: A literature review identified the clinical features of all published GlyR-Ab-positive cases through online databases. A case series was undertaken via collection of clinical information from all patients diagnosed or known to immunology, pathology or neurological services in Queensland during the study period of 3 years. RESULTS: In all, 187 GlyR-Ab-positive cases were identified in the literature. The majority (47.6%) had PERM, 22.4% had epilepsy, but the remaining 30% included mixed phenotypes consisting of cerebellar ataxia, movement disorders, demyelination and encephalitis/cognitive dysfunction. By contrast, in our series of 14 cases, eight had clinical presentations consistent with seizures and epilepsy and only three cases had classical features of PERM. There was one case each of global fatiguable weakness with sustained clonus, laryngeal dystonia and movement disorder with hemiballismus and tics. The rate of response to immune therapy was similar in all groups. CONCLUSION: Antibodies to glycine receptors are linked to a spectrum of neurological disease. The results of the literature review and our case series suggest a greater relationship between GlyR-Abs and epilepsy than previously reported.


Asunto(s)
Autoanticuerpos , Rigidez Muscular/inmunología , Mioclonía/inmunología , Receptores de Glicina/inmunología , Adolescente , Adulto , Anciano , Australia , Niño , Preescolar , Encefalitis/inmunología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/inmunología , Fenotipo , Adulto Joven
9.
Osteoporos Int ; 26(9): 2257-63, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25860976

RESUMEN

UNLABELLED: The Fracture Liaison Service (FLS) is advocated to be effective for the prevention of secondary fractures, but implementation is variable. A questionnaire based on the International Osteoporosis Foundation (IOF) Capture the Fracture® FLS standards was used in the current study. The results showed high compliancy with the IOF standards in the Dutch responding hospitals. INTRODUCTION: The FLS is advocated for the prevention of secondary fractures, but its implementation varies between hospitals and countries. The present survey applied the standards proposed by the IOF to evaluate the implementation of FLSs in non-university hospitals in the Netherlands. METHODS: A questionnaire based on the IOF FLS standards was used in this study, requesting the selection, evaluation and treatment data of patients older than 50 years with a recent fracture. RESULTS: Of 90 invited hospitals, 24 (27 %) fully responded, providing data of 24,468 consecutive patients, corresponding with 25 % of fracture patients in the Netherlands in the year 2012. After excluding skull and toe fractures and patients exceeding the upper age limits applied by individual hospitals, 11,983 patient data were available for analysis. The data showed high compliance (>90 %) for fracture patient identification, invitation for FLS, timing of assessment, identification of vertebral fractures, application of national guidelines, evaluation of secondary osteoporosis, drug initiation when indicated, communication with the general practitioner and application of follow-up strategy and 70 % for fall prevention. The response rate was on average (49 %). CONCLUSIONS: The available data also showed that patients attending the FLSs were evaluated, treated and followed in high compliancy with the IOF standards. Some standards are open to different interpretations and may need further specification. The major shortcoming in FLS practice was that patients invited to attend the FLSs showed a low response rate. None of the hospitals achieved the IOF standard patient response rate of over 90 %.


Asunto(s)
Fracturas Osteoporóticas/prevención & control , Prevención Secundaria/normas , Accidentes por Caídas/prevención & control , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/uso terapéutico , Utilización de Medicamentos/estadística & datos numéricos , Adhesión a Directriz/estadística & datos numéricos , Encuestas de Atención de la Salud , Humanos , Persona de Mediana Edad , Países Bajos/epidemiología , Osteoporosis/diagnóstico , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Factores de Riesgo , Prevención Secundaria/métodos , Prevención Secundaria/organización & administración , Fracturas de la Columna Vertebral/prevención & control , Encuestas y Cuestionarios
10.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37874231

RESUMEN

We present the design and characterization of a cryogenic window based on an ultra-thin aluminized biaxially oriented polyethylene terephthalate foil at T < 10 K, which can withstand a pressure difference larger than 1 bar at a leak rate <1×10-9 mbar l/s. Its thickness of ∼1.7 µm makes it transparent to various types of particles over a broad energy range. To optimize the transfer of 100 keV antiprotons through the window, we tested the degrading properties of different aluminum coated polymer foils of thicknesses between 900 and 2160 nm, concluding that 1760 nm foil decelerates antiprotons to an average energy of 5 keV. We have also explicitly studied the permeation as a function of coating thickness and temperature and have performed extensive thermal and mechanical endurance and stress tests. Our final design integrated into the experiment has an effective open surface consisting of seven holes with a diameter of 1 mm and will transmit up to 2.5% of the injected 100 keV antiproton beam delivered by the Antiproton Decelerator and Extra Low ENergy Antiproton ring facility of CERN.

11.
Rev Sci Instrum ; 94(11)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37972020

RESUMEN

Currently, the world's only source of low-energy antiprotons is the AD/ELENA facility located at CERN. To date, all precision measurements on single antiprotons have been conducted at this facility and provide stringent tests of fundamental interactions and their symmetries. However, magnetic field fluctuations from the facility operation limit the precision of upcoming measurements. To overcome this limitation, we have designed the transportable antiproton trap system BASE-STEP to relocate antiprotons to laboratories with a calm magnetic environment. We anticipate that the transportable antiproton trap will facilitate enhanced tests of charge, parity, and time-reversal invariance with antiprotons and provide new experimental possibilities of using transported antiprotons and other accelerator-produced exotic ions. We present here the technical design of the transportable trap system. This includes the transportable superconducting magnet, the cryogenic inlay consisting of the trap stack and detection systems, and the differential pumping section to suppress the residual gas flow into the cryogenic trap chamber.

12.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38109470

RESUMEN

We present a fluorescence-detection system for laser-cooled 9Be+ ions based on silicon photomultipliers (SiPMs) operated at 4 K and integrated into our cryogenic 1.9 T multi-Penning-trap system. Our approach enables fluorescence detection in a hermetically sealed cryogenic Penning-trap chamber with limited optical access, where state-of-the-art detection using a telescope and photomultipliers at room temperature would be extremely difficult. We characterize the properties of the SiPM in a cryocooler at 4 K, where we measure a dark count rate below 1 s-1 and a detection efficiency of 2.5(3)%. We further discuss the design of our cryogenic fluorescence-detection trap and analyze the performance of our detection system by fluorescence spectroscopy of 9Be+ ion clouds during several runs of our sympathetic laser-cooling experiment.

13.
Rheumatol Int ; 32(8): 2487-90, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21833530

RESUMEN

Adult-onset Still's disease (AOSD) is known as a systemic inflammatory disease of unknown etiology and pathogenesis, characterized by fever, skin eruptions, systemic organ involvement, and arthralgias. AOSD is difficult to diagnose because of its heterogeneous clinical manifestations and prevalence (although more prevalent in the young, onset of AOSD after the age of 60 has also been described), and absence of pathognomonic clinical features. The disease also lacks a specific diagnostic test. To date, association studies between AOSD and HLA loci have failed to indentify a genetic predisposition. The recent publication of entirely different PET-CT manifestations found in three patients who were supposed to have the same disease (AOSD), as well as the surprisingly different PET-CT images of our AOSD patient (accumulation in the carotids and large vessels of the legs), raises our suspicion that AOSD is actually not one entity but a constellation of disorders whose varying underlying pathologies are now being revealed by new imaging techniques.


Asunto(s)
Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Extremidad Inferior/irrigación sanguínea , Imagen Multimodal , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Enfermedad de Still del Adulto/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Imagen de Cuerpo Entero , Adulto , Antiinflamatorios no Esteroideos/uso terapéutico , Biopsia , Enfermedades de las Arterias Carótidas/tratamiento farmacológico , Enfermedades de las Arterias Carótidas/etiología , Quimioterapia Combinada , Glucocorticoides/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/tratamiento farmacológico , Enfermedades Vasculares Periféricas/etiología , Valor Predictivo de las Pruebas , Enfermedad de Still del Adulto/clasificación , Enfermedad de Still del Adulto/complicaciones , Enfermedad de Still del Adulto/tratamiento farmacológico , Resultado del Tratamiento
14.
Biomed Opt Express ; 13(10): 5151-5170, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36425615

RESUMEN

Fluorescence lifetime imaging ophthalmoscopy (FLIO), a technique for investigating metabolic changes in the eye ground, can reveal the first signs of diseases related to metabolism. The fluorescence of the natural lens overlies the fundus fluorescence. Although the influence of natural lens fluorescence can be somewhat decreased with mathematical models, excluding this influence during the measurement by using hardware enables more exact estimation of the fundus fluorescence. Here, we analyze four 1-photon excitation hardware solutions to suppress the influence of natural lens fluorescence: aperture stop separation, confocal scanning laser ophthalmoscopy, combined confocal scanning laser ophthalmoscopy and aperture stop separation, and dual point confocal scanning laser ophthalmoscopy. The effect of each principle is demonstrated in examples. The best suppression is provided by the dual point principle, realized with a confocal scanning laser ophthalmoscope. In this case, in addition to the fluorescence of the whole eye, the fluorescence of the anterior part of the eye is detected from a non-excited spot of the fundus. The intensity and time-resolved fluorescence spectral data of the fundus are derived through the subtraction of the simultaneously measured fluorescence of the excited and non-excited spots. Advantages of future 2-photon fluorescence excitation are also discussed. This study provides the first quantitative evaluation of hardware principles to suppress the fluorescence of the natural lens during measurements of fundus autofluorescence.

15.
Klin Monbl Augenheilkd ; 228(1): 57-61, 2011 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-20714991

RESUMEN

Determination of the optical density of the macular pigment may be used for an assessment of the efficacy of oral lutein supplementation in patients with dry AMD. Beside subjective methods like heterochrome flicker photometry, objective methods like the 2-wavelength auto-fluorescence method and the 1-wavelength reflection method are in clinical use today. Both methods show comparable results. For a long-term assessment of the efficacy of oral lutein supplementation, different parameters like mean and maximal optical density as well as the integral over optical density on all pixels ("volume") should be used. The parameter volume often increases also in cases in which other parameters do not change anymore. The 1-wavelength reflection method is used for the newly initiated LUTEGA study. This study will investigate the long-term effects of a fixed lutein/omega-3-fatty acid combination on the optical density in patients with dry AMD.


Asunto(s)
Densitometría/métodos , Técnicas de Diagnóstico Oftalmológico , Ácidos Grasos Omega-3/uso terapéutico , Luteína/uso terapéutico , Degeneración Macular/diagnóstico , Degeneración Macular/tratamiento farmacológico , Pigmentos Retinianos/análisis , Anciano , Anciano de 80 o más Años , Suplementos Dietéticos , Femenino , Humanos , Degeneración Macular/metabolismo , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
16.
Nat Commun ; 12(1): 5920, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34635664

RESUMEN

The carbon/oxygen (C/O) ratio at the end of stellar helium burning is the single most important nuclear input to stellar evolution theory. However, it is not known with sufficient accuracy, due to large uncertainties in the cross-section for the fusion of helium with 12C to form 16O, denoted as 12C(α, γ)16O. Here we present results based on a method that is significantly different from the experimental efforts of the past four decades. With data measured inside one detector and with vanishingly small background, angular distributions of the 12C(α, γ)16O reaction were obtained by measuring the inverse 16O(γ, α)12C reaction with gamma-beams and a Time Projection Chamber (TPC) detector. We agree with current world data for the total reaction cross-section and further evidence the strength of our method with accurate angular distributions measured over the 1- resonance at Ecm ~ 2.4 MeV. Our technique promises to yield results that will surpass the quality of the currently available data.

17.
Phys Rev Lett ; 104(20): 206406, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20867047

RESUMEN

The charge response of a charge-ordered state in the organic conductor α-(BEDT-TTF)2I3 is characterized by dc resistivity, dielectric and optical spectroscopy in different crystallographic directions within the two-dimensional conduction layer. Two dielectric modes are detected. The large mode is related to the phasonlike excitation of the 2k(F) bond-charge density wave which forms in the ab plane. The small dielectric mode is associated with the motion of domain-wall pairs along the a and b axes between two types of domains which are created due to inversion symmetry breaking.

18.
Obstet Med ; 13(4): 192-194, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33343696

RESUMEN

Paramyotonia congenita is a rare autosomal dominant non-dystrophic myopathy caused by mutations in the SNC4A gene, which encodes for the voltage-gated sodium channel in skeletal muscle. Symptom onset is typically during early childhood and is characterised by myotonia followed by flaccid paralysis or weakness, usually exacerbated by repeated muscle contractions or cold temperatures. Pregnancy has been reported to increase symptoms of myotonia; however, there is limited information in the literature regarding the possible effects of paramyotonia congenita on pregnancy and labour. We present a successful case of a 20-year-old primigravida with confirmed paramyotonia congenita and review the literature regarding paramyotonia congenita during pregnancy.

19.
Biomed Opt Express ; 11(10): 5586-5602, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33149973

RESUMEN

Fluorescence lifetime imaging ophthalmoscopy (FLIO) has developed as a new diagnostic tool in ophthalmology. FLIO measurements are taken from 30° retinal fields in two spectral channels (short spectral channel (SSC): 498-560 nm, long spectral channel (LSC): 560-720 nm). Because of the layered structure of the eye, the detected signal is an interaction of the fluorescence decay of the anterior part and of the fundus. By comparing FLIO measurements before and after cataract surgery, the impact of the natural lens was proven, despite the application of a confocal laser scanning (cSLO) technique. The goal of this work was to determine the best algorithmic solution to isolate the sole fundus fluorescence lifetime from the measured signal, suppressing artifacts from the natural lens. Three principles based on a tri-exponential model were investigated: a tailfit, a layer-based approach with a temporally shifted component, and the inclusion of a separately measured fluorescence decay of the natural lens. The mean fluorescence lifetime τm,12 is calculated using only the shortest and the intermediate exponential component. τm,all is calculated using all three exponential components. The results of tri-exponential tailfit after cataract surgery were considered as a reference, because the implanted artificial lens can be assumed as non-fluorescent. In SSC, the best accordance of τm,all of the reference was determined with τm,12 of the tailfit before surgery. If high-quality natural lens measurements are available, the correspondence of τm,12 is best with τm,all of the reference. In LSC, there is a good accordance for all models between τm,12 before and after surgery. To study the pure fundus fluorescence decay in eyes with natural lenses, we advise to utilize fluorescence lifetime τm,12 of a triple-exponential tailfit, as it corresponds well with the mean fluorescence lifetime τm,all of eyes with fluorescence-less artificial intraocular lenses.

20.
Ned Tijdschr Geneeskd ; 162: D1817, 2018.
Artículo en Holandés | MEDLINE | ID: mdl-29676705

RESUMEN

An 85-year-old man came to the emergency room because of vomiting a black fluid and melaena. He was hypotensive and had severe anaemia. We suspected an upper digestive tract bleeding and a gastroscopy was performed, which showed necrosis of the entire oesophagus. Within 24 hours of admission the patient died of hypovolemic shock.


Asunto(s)
Enfermedades del Esófago/patología , Esófago/patología , Vómitos/etiología , Anciano de 80 o más Años , Enfermedades del Esófago/complicaciones , Resultado Fatal , Humanos , Masculino , Necrosis
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