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1.
Nature ; 479(7372): 215-8, 2011 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-22071767

RESUMEN

The origin of lunar magnetic anomalies remains unresolved after their discovery more than four decades ago. A commonly invoked hypothesis is that the Moon might once have possessed a thermally driven core dynamo, but this theory is problematical given the small size of the core and the required surface magnetic field strengths. An alternative hypothesis is that impact events might have amplified ambient fields near the antipodes of the largest basins, but many magnetic anomalies exist that are not associated with basin antipodes. Here we propose a new model for magnetic field generation, in which dynamo action comes from impact-induced changes in the Moon's rotation rate. Basin-forming impact events are energetic enough to have unlocked the Moon from synchronous rotation, and we demonstrate that the subsequent large-scale fluid flows in the core, excited by the tidal distortion of the core-mantle boundary, could have powered a lunar dynamo. Predicted surface magnetic field strengths are on the order of several microteslas, consistent with palaeomagnetic measurements, and the duration of these fields is sufficient to explain the central magnetic anomalies associated with several large impact basins.

2.
Phys Rev Lett ; 117(15): 158101, 2016 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-27768366

RESUMEN

The x-ray dark-field signal measured in grating interferometers is anisotropic, depending on both the beam direction and the grating orientation with respect to the sample. We present a novel general closed-form, continuous forward model of the anisotropic dark-field signal. Furthermore, we derive a discretization using spherical harmonics, leading to a large-scale linear inverse problem. We present first experimental results of a wooden sample, demonstrating marked advantages over previous results, in particular, the resolution of multiple scattering directions in one volume element.

3.
Scand J Rheumatol ; 44(6): 487-94, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26271272

RESUMEN

OBJECTIVES: Endogenous cognitive event-related potentials (CERPs) reflect higher-level processing of sensory information and can be used to evaluate cognitive functions. The aim of this paper was to determine whether there are any abnormalities in the electrophysiological parameters of CERPs in patients with primary Sjögren's syndrome (pSS) but without symptoms of central nervous system (CNS) involvement or mental disorder. The analysis of CERP parameters was then correlated with the clinical status of the patients and with some of the immunological parameters in the patient group. METHOD: Thirty consecutive patients with pSS (29 females, one male) were included in the study. All the patients underwent CERP examination. RESULTS: There was a significant prolongation of the latency of P300 and N200 potentials in patients with pSS. Abnormalities in electrophysiological parameters of CERPs correlated with the duration of the disease, salivary gland abnormalities, and elevated erythrocyte sedimentation rate (ESR) values. Patients with coexisting chronic fatigue syndrome (CFS) had larger P300 amplitudes. There were no statistically significant changes in the electrophysiological parameters of CERPs in patients with pSS dependent on the presence of peripheral nervous system (PNS) lesions, skin changes, arthritis, abnormalities in white blood cells and the immune system or the levels of blood lipids. CONCLUSIONS: The results of the study suggest the presence of a minor cognitive dysfunction in patients with pSS without symptoms of CNS involvement or mental disorder. Cognitive dysfunction correlated with the disease duration time and the severity of inflammatory changes (salivary gland abnormalities and inflammatory markers in the blood). Further and larger longitudinal studies are necessary for confirmation of this correlation.


Asunto(s)
Sistema Nervioso Central/fisiología , Cognición/fisiología , Potenciales Relacionados con Evento P300/fisiología , Potenciales Evocados/fisiología , Síndrome de Sjögren/fisiopatología , Síndrome de Sjögren/psicología , Estimulación Acústica , Adulto , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Progresión de la Enfermedad , Fenómenos Electrofisiológicos/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología , Glándulas Salivales/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Síndrome de Sjögren/sangre , Ultrasonografía
4.
J Med Virol ; 86(7): 1243-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24123142

RESUMEN

The study describes genetic characterization of poliovirus (PV) strains isolated from sewage samples in Poland. The analyses were performed for the detection of any putative polio revertants and recombinants in three genomic regions by sequencing analysis. Thirty-six strains were analyzed. The analyzed strains were identified by neutralization assay as 7 strains of serotype P1, 10 strains of serotype P2, and 19 strains of serotype P3. Sewage isolates were sequenced in 5'UTR, VP1, and 3D genomic regions. All detected PVs were classified as vaccine strains on the basis of VP1 sequence. Mutational differences in the VP1 sequences of isolated viruses ranged from 0.0% to 0.4%, indicating a limited replication period. The genetic analysis of the 3D region showed that some strains have recombinant genomes. Nine strains were found as dipartite recombinants (seven strains--S3/S2, one strain--S2/S1, one strain--S3/S1), while one strain was found as tripartite recombinant (S3/S2/S1). No recombinants with non-PV enteroviruses were identified. None of wild-type PVs or vaccine-derived polioviruses (VDPVs) were detected. This study showed the absence of wild or VDPV circulation in the country and demonstrated the usefulness of environmental surveillance in addition to acute flaccid paralysis (AFP) surveillance in support of polio eradication initiatives.


Asunto(s)
Poliovirus/clasificación , Poliovirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Regiones no Traducidas 5' , Proteínas de la Cápside/genética , Humanos , Mutación , Pruebas de Neutralización , Polonia , Poliovirus/genética , ARN Viral/genética , ARN Polimerasa Dependiente del ARN/genética , Recombinación Genética , Análisis de Secuencia de ADN , Serotipificación
5.
J Frailty Aging ; 12(1): 71-77, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36629088

RESUMEN

BACKGROUND: The benefits of supplemental vitamin D3, marine omega-3 fatty acids, and a simple home exercise program (SHEP) on frailty prevention in generally healthy community-dwelling older adults are unclear. OBJECTIVE: To test the effect of vitamin D3, omega-3s, and a SHEP, alone or in combination on incident pre-frailty and frailty in robust older adults over a follow-up of 36 months. METHODS: DO-HEALTH is a multi-center, double-blind, placebo-controlled, 2x2x2 factorial randomized clinical trial among generally healthy European adults aged 70 years or older, who had no major health events in the 5 years prior to enrollment, sufficient mobility and intact cognitive function. As a secondary outcome of the DO-HEALTH trial, among the subset of participants who were robust at baseline, we tested the individual and combined benefits of supplemental 2,000 IU/day of vitamin D3, 1 g/day of marine omega-3s, and a SHEP on the odds of being pre-frail and frail over 3 years of follow-up. RESULTS: At baseline, 1,137 out of 2,157 participants were robust (mean age 74.3 years, 56.5% women, mean gait speed 1.18 m/s). Over a median follow-up time of 2.9 years, 696 (61.2%) became pre-frail and 29 (2.6%) frail. Odds ratios for becoming pre-frail were not significantly lower for vitamin D3, or omega 3-s, or SHEP, individually, compared to control (placebo for the supplements and control exercise). However, the three treatments combined showed significantly decreased odds (OR 0.61 [95% CI 0.38-0.98; p=0.04) of becoming pre-frail compared to control. None of the individual treatments or their combination significantly reduced the odds of becoming frail. CONCLUSION: Robust, generally healthy and active older adults without major comorbidities, may benefit from a combination of high-dose, supplemental vitamin D3, marine omega-3s, and SHEP with regard to the risk of becoming pre-frail over 3 years.


Asunto(s)
Ácidos Grasos Omega-3 , Fragilidad , Humanos , Femenino , Anciano , Masculino , Vitamina D , Fragilidad/prevención & control , Fragilidad/tratamiento farmacológico , Vitaminas/uso terapéutico , Ácidos Grasos Omega-3/uso terapéutico , Colecalciferol/uso terapéutico , Suplementos Dietéticos , Terapia por Ejercicio
6.
Europace ; 14(12): 1700-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22772054

RESUMEN

AIMS: Duty-cycled radiofrequency ablation (RFA) has been used for atrial fibrillation (AF) for around 5 years, but large-scale data are scarce. The purpose of this survey was to report the outcome of the technique. METHODS AND RESULTS: A survey was conducted among 20 centres from seven European countries including 2748 patients (2128 with paroxysmal and 620 with persistent AF). In paroxysmal AF an overall success rate of 82% [median 80%, interquartile range (IQR) 74-90%], a first procedure success rate of 72% [median 74% (IQR 59-83%)], and a success of antiarrhythmic medication of 59% [median 60% (IQR 39-72%)] was reported. In persistent AF, success rates were significantly lower with 70% [median 74% (IQR 60-92%)]; P = 0.05) as well as the first procedure success rate of 58% [median 55% (IQR 47-81%)]; P = 0.001). The overall success rate was similar among higher and lower volume centres and were not dependent on the duration of experience with duty-cycled RFA (r = -0.08, P = 0.72). Complications were observed in 108 (3.9%) patients, including 31 (1.1%) with symptomatic transient ischaemic attack or stroke, which had the same incidence in paroxysmal and persistent AF (1.1 vs. 1.1%) and was unrelated to the case load (r = 0.24, P = 0.15), bridging anticoagulation to low molecular heparin, routine administration of heparin over the long sheath, whether a transoesophageal echocardiogram was performed in every patient or not and average procedure times. CONCLUSION: Duty-cycled RFA has a self-reported success and complication rate similar to conventional RFA. After technical modifications a prospective registry with controlled data monitoring should be conducted to assess outcome.


Asunto(s)
Fibrilación Atrial/epidemiología , Fibrilación Atrial/cirugía , Ablación por Catéter/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Recolección de Datos , Europa (Continente)/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
7.
Parasitol Res ; 110(6): 2363-71, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22205349

RESUMEN

Toxocariasis is a helminthozoonotic disease caused by ascarid larvae of Toxocara genus: Toxocara canis and Toxocara cati. In the reported study, the clinical course of toxocariasis and administered therapy were evaluated in 103 children. The majority of the children (68.9%) were from the rural environment, with a prevalence of boys (62.1%). At diagnosis of infection, 36 (35%) children reported recurrent abdominal pain, 19 (18.4%) headache, 6 (5.8%) loss of appetite, 2 subfebrile conditions, and 2 arthralgia, Moreover, 23 (22.3%) children demonstrated symptoms of atopic diseases; in 30 (29.1%) children, moderate enlargement of lymphatic nodes was noted. In five children (4.9%), ophthalmic examination revealed unilateral changes in the eye: in two cases retinitis; in one case fibrotic lesions in the vitreous body, complicated 1 year from diagnosis by retinal detachment; and in other children parafoveal lesions and cataract. Only two children with ocular changes at diagnosis reported visual disorders. In 64.3% of children, eosinophilia was observed. A covert form of the disease was diagnosed in 95.1% of the children and an ocular form in 4.9%. In all the children, antiparasitic treatment was implemented, repeated several times in some of them. After therapy, the mean titer of specific antibodies, the number of children with abdominal pains and enlarged lymphatic nodes were decreased, while headaches maintained at unchanged levels. In approximately one fourth of the children with negative results of antibodies after the therapy, the symptoms of the disease were still reported. Evaluation of the efficacy of treatment is not easy due to non-characteristic symptoms and low kinetics of specific anti Toxocara IgG decrease; however, high IgG titers suggest non-effective treatment of concomitant infection requiring subsequent therapy. Due to risk of ocular form, which may develop in any stage of the disease, irrespectively of specific antibodies concentrations, it seems justified to implement antiparasitic treatment in all children infected with T. canis.


Asunto(s)
Antihelmínticos/administración & dosificación , Toxocara canis/aislamiento & purificación , Toxocariasis/tratamiento farmacológico , Toxocariasis/patología , Adolescente , Animales , Anticuerpos Antihelmínticos/sangre , Niño , Preescolar , Femenino , Humanos , Lactante , Estudios Longitudinales , Masculino , Toxocara canis/inmunología , Toxocariasis/parasitología , Resultado del Tratamiento
8.
J Nutr Health Aging ; 26(9): 864-871, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36156678

RESUMEN

OBJECTIVES: To assess if baseline iron deficiency, with or without anemia, is associated with incident infections over 3 years among community-dwelling older adults. DESIGN: Prospective secondary analysis of DO-HEALTH, a 3-year randomized, double-blind controlled trial. SETTING AND PARTICIPANTS: 2157 community-dwelling adults age 70+ from 5 European countries with good cognitive function and mobility and no major health events in the 5 years prior to enrollment Measurements: Incident infections, their severity and type were recorded every 3 months throughout the 3-year follow-up. Iron deficiency was defined as soluble transferrin receptor (sTfR) levels > 28.1 nmol/l and anemia as hemoglobin levels < 120 g/l for women and 130 g/l for men. We applied negative binomial mixed effects regression models with random effects for countries, and controlling for treatment allocation, age, sex, body mass index, polypharmacy, number of comorbidities, smoking status, living situation, alcohol intake, frailty status, and physical activity levels. A pre-defined stratified analysis was performed to explore if the associations between iron deficiency and infections were consistent by baseline anemia status. RESULTS: In total, 2141 participants were included in the analyses (mean age 74.9 years, 61.5% of women, 26.8% with iron deficiency). Across all participants, baseline iron deficiency was not associated with incident overall infections, but was associated with a 63% greater rate of incident severe infections requiring hospitalization (incidence rate ratio [IRR] 1.63, 95% Confidence Interval [CI] 1.11-2.41, p=0.01). This association was more pronounced among the 2000 participants who did not have anemia at baseline (IRR=1.80, 95% CI 1.20-2.69, p=0.005). CONCLUSION: Based on this prospective study among generally healthy European community-dwelling older adults, iron deficiency was not associated with the incidence rate of overall infections but may increase the incidence of severe infections. Intervention studies are needed to prove the causality of this observation.


Asunto(s)
Anemia Ferropénica , Anemia , Deficiencias de Hierro , Anciano , Anemia Ferropénica/epidemiología , Femenino , Hemoglobinas , Humanos , Vida Independiente , Hierro , Masculino , Estudios Prospectivos , Receptores de Transferrina
9.
Science ; 378(6618): 417-421, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36302020

RESUMEN

We detected surface waves from two meteorite impacts on Mars. By measuring group velocity dispersion along the impact-lander path, we obtained a direct constraint on crustal structure away from the InSight lander. The crust north of the equatorial dichotomy had a shear wave velocity of approximately 3.2 kilometers per second in the 5- to 30-kilometer depth range, with little depth variation. This implies a higher crustal density than inferred beneath the lander, suggesting either compositional differences or reduced porosity in the volcanic areas traversed by the surface waves. The lower velocities and the crustal layering observed beneath the landing site down to a 10-kilometer depth are not a global feature. Structural variations revealed by surface waves hold implications for models of the formation and thickness of the martian crust.

10.
Nat Commun ; 12(1): 5433, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34521860

RESUMEN

The lunar cratering record is used to constrain the bombardment history of both the Earth and the Moon. However, it is suggested from different perspectives, including impact crater dating, asteroid dynamics, lunar samples, impact basin-forming simulations, and lunar evolution modelling, that the Moon could be missing evidence of its earliest cratering record. Here we report that impact basins formed during the lunar magma ocean solidification should have produced different crater morphologies in comparison to later epochs. A low viscosity layer, mimicking a melt layer, between the crust and mantle could cause the entire impact basin size range to be susceptible to immediate and extreme crustal relaxation forming almost unidentifiable topographic and crustal thickness signatures. Lunar basins formed while the lunar magma ocean was still solidifying may escape detection, which is agreeing with studies that suggest a higher impact flux than previously thought in the earliest epoch of Earth-Moon evolution.

11.
J Geophys Res Planets ; 126(11): e2021JE006983, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34824966

RESUMEN

Seismological constraints obtained from receiver function (RF) analysis provide important information about the crust and mantle structure. Here, we explore the utility of the free-surface multiple of the P-wave (PP) and the corresponding conversions in RF analysis. Using earthquake records, we demonstrate the efficacy of PPs-RFs before illustrating how they become especially useful when limited data is available in typical planetary missions. Using a transdimensional hierarchical Bayesian deconvolution approach, we compute robust P-to-S (Ps)- and PPs-RFs with InSight recordings of five marsquakes. Our Ps-RF results verify the direct Ps converted phases reported by previous RF analyses with increased coherence and reveal other phases including the primary multiple reverberating within the uppermost layer of the Martian crust. Unlike the Ps-RFs, our PPs-RFs lack an arrival at 7.2 s lag time. Whereas Ps-RFs on Mars could be equally well fit by a two- or three-layer crust, synthetic modeling shows that the disappearance of the 7.2 s phase requires a three-layer crust, and is highly sensitive to velocity and thickness of intra-crustal layers. We show that a three-layer crust is also preferred by S-to-P (Sp)-RFs. While the deepest interface of the three-layer crust represents the crust-mantle interface beneath the InSight landing site, the other two interfaces at shallower depths could represent a sharp transition between either fractured and unfractured materials or thick basaltic flows and pre-existing crustal materials. PPs-RFs can provide complementary constraints and maximize the extraction of information about crustal structure in data-constrained circumstances such as planetary missions.

12.
Herzschrittmacherther Elektrophysiol ; 31(1): 10-19, 2020 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-32055926

RESUMEN

With an estimated incidence of approximated 36 per 100,000 persons per year, paroxysmal supraventricular tachycardias form a relevant clinical set of problems. They occur based on different substrates with varied symptoms and electrocardiographic items. The 12-channel ECG depicts the background to determine the underlying pathomechanism. The sinus node and all components of the conduction system such as atrial myocardium can be involved. Vagal maneuvers, several pharmacological strategies and various ablation technology are available for acute therapy.


Asunto(s)
Ablación por Catéter , Taquicardia Supraventricular , Electrocardiografía , Atrios Cardíacos , Sistema de Conducción Cardíaco , Humanos
13.
J Geophys Res Planets ; 125(3): e2019JE006296, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32714727

RESUMEN

Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m-3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low-iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron-rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma-ray spectrometer) will produce data sets that distinguish among the models.

14.
J Pineal Res ; 46(2): 214-23, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19141087

RESUMEN

The relationship between germination and melatonin applied during osmo- and hydropriming was studied in cucumber seeds. The proportion of nuclei with different DNA contents, the mean ploidy and the (2C + 4C = 8C)/2C ratio in unprimed and primed, dry and imbibed at 10 degrees C seeds were established by flow cytometry. Thiobarbituric acid reactive substances and protein oxidation were also estimated. Melatonin and indole-3-acetic acid (IAA) concentrations in the seeds were determined using high-performance liquid chromatography with electrochemical detection. Being sensitive to chilling stress, seeds that germinated well (99%) at 25 degrees C showed only 30% germination at 15 degrees C, and almost no germination (4%) at 10 degrees C. Hydropriming in water improved seed germination to 50-60% at 15 degrees C and the addition of melatonin (25-100 M) also increased the rate of germination. Osmopriming in polyethylene glycol increased germination at 15 degrees C to 78%, and 98% when combined with 50 M melatonin. Osmoprimed seeds germinated even at 10 degrees C and reached 43%, and 83% when 50 M melatonin was applied. None of the treatments induced DNA synthesis, although during the first 24 hr of imbibition at 10 degrees C the mean ploidy and the (2C + 4C = 8C)/2C ratio increased, which is indicative of the advanced Phase II of germination. Hydro- and osmopriming slightly decreased IAA content in the seeds in most of the cases; only hydropriming with 100 and 500 M melatonin increased it. Melatonin protected membrane structure against peroxidation during chilling, but excessive melatonin levels in cucumber seeds (approximately 4 microg/g fresh weight) provoked oxidative changes in proteins. There is still lack of information explained clearly the role of melatonin in plant physiology. This molecule acts multidirectionally and usually is alliged to other compounds.


Asunto(s)
Antioxidantes/farmacología , Cucumis sativus/crecimiento & desarrollo , Germinación/efectos de los fármacos , Melatonina/farmacología , Semillas/metabolismo , Estrés Fisiológico/efectos de los fármacos , Frío
15.
Sci Rep ; 7(1): 3195, 2017 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-28600544

RESUMEN

Anisotropic X-ray Dark-field Tomography (AXDT) is a new imaging technique for reconstructing the three-dimensional scattering profile within a sample using the dark-field signal measured in an X-ray grating interferometry setup. As in any tomographic measurement, the acquisition geometry plays a key role in the accurate reconstruction of the scattering information. More- over, the anisotropic nature of the dark-field signal poses additional challenges for designing the acquisition protocols. In this work, we present an efficient approach to measure scattering orientations spread over the unit sphere and prove its efficacy using the knowledge from conventional tomography. In addition, we conclude (using analytical and experimental results) that placing the gratings such that the grating bars make an angle of 45 degrees with respect to the vertical direction is the optimal setup configuration for AXDT.

16.
Talanta ; 171: 275-282, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28551141

RESUMEN

The proposed approach to two-component speciation analysis relies on simultaneous application of two calibration methods to determination of two different forms of an analyte. One form is determined in extrapolative way, whereas the second form is determined in interpolative way, with the use of the same calibration graph, after appropriate chemical treatment, e.g. oxidation or reduction. The applicability of the approach has been verified on the examples of spectrophotometric determinations of Fe(II)/Fe(III) and Cr(VI)/Cr(III) using 1,10-phenanthroline and 1,5-diphenylcarbazide methods, respectively. In the above methods, ascorbic acid and Ce(IV) have been used to reduce Fe(III) to Fe(II) and to oxidize Cr(III) to Cr(VI), respectively. Lab-In-Syringe and SIA systems (for determination of iron and chromium species, respectively) have been applied to make the implementation of the proposed approach more convenient. The approach was verified on the example of determination of the analytes in synthetic and certified reference materials of ground and waste water samples. Using the developed methods, Fe(II)/Fe(III) and Cr(VI)/Cr(III) were determined within the concentration ranges of 0.06-4.0/0.06-3.0 and 0.03-0.5/0.05-7.0mgL-1, with precision (RSD, %) less than 3.8/2.0 and 2.2/6.0, and accuracy (RE, %) better than 2.9/4.3 and 6.8/5.2, respectively. The detection limits (mgL-1) are 0.02/0.02 and 0.01/0.02 for determination of both forms of iron and chromium, respectively. The applicability of the approach has been checked by analysis of artesian water (Fe(II)/Fe(III)) and post-production waste samples (Cr(III)/Cr(VI)).

17.
Artículo en Alemán | MEDLINE | ID: mdl-16547653

RESUMEN

We present a patient with an accessory pathway difficult to ablate in the right free wall. Two prolonged and failed attempts at radiofrequency catheter ablation of this accessory pathway in other institutions led to a third attempt in our hospital. Successful outcome of accessory pathway ablation was achieved by mapping the right free wall using an intracoronary catheter in the right coronary artery. A long vascular sheeth was introduced in the right femoral vein, manipulated into the tricuspid anulus, which allowed a stable catheter position with adequate tissue contact of the ablation catheter at the target site. The combination of exact mapping and adequate tissue contact of the ablation catheter as described above facilitated successful outcome in this patient. Further investigation is necessary to determine the role of this technique as first choice therapy in patients prone to develop recurrence of accessory pathway conduction or primary failure of catheter ablation.


Asunto(s)
Mapeo del Potencial de Superficie Corporal/métodos , Cateterismo Cardíaco/métodos , Ablación por Catéter/métodos , Vasos Coronarios/fisiopatología , Sistema de Conducción Cardíaco/anomalías , Sistema de Conducción Cardíaco/cirugía , Adulto , Mapeo del Potencial de Superficie Corporal/instrumentación , Cateterismo Cardíaco/instrumentación , Ablación por Catéter/instrumentación , Humanos , Masculino , Resultado del Tratamiento
18.
Herzschrittmacherther Elektrophysiol ; 17(2): 106-11, 2006 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-16786469

RESUMEN

We report the case of a 35-year-old man who was suffering from severe heart failure due to cardiomyopathy. He underwent heart transplantation years ago and developed complex ventricular arrhythmias in the following months in combination with recurrent episodes of syncope due to hypertrophic non-obstructive cardiomyopathy in the transplanted heart, so a dual chamber ICD was implanted. Months later repetitive episodes of intermittent T-wave oversensing with consecutive activation of the ICD could be observed. Surgical revision of the electrode was performed and the patient was closely followed up. One year later, further episodes of T-wave oversensing led to multiple inappropriate IDC-shocks. A very short AV-conduction time was programmed to allow ventricular capture whenever possible, because T-wave oversense after ventricular capture would be annotated as single ventricular ectopy not resulting in antitachycardia pacing. As a consequence, the patient was free from inappropriate ICD-shocks, but showed several shorter episodes of T-wave oversensing. They were all initiated by atrial activity that was seen in the refractory period, thus leading to a loss of AV synchrony. Programming a very short post ventricular atrial refractory period (PVARP) in addition to a short AV-delay led to the complete disappearance of T-wave oversensing in this patient. During a 9-month follow-up, no further tachycardia episodes were detected by the device.


Asunto(s)
Desfibriladores Implantables/efectos adversos , Electrocardiografía/métodos , Taquicardia Ventricular/etiología , Taquicardia Ventricular/prevención & control , Terapia Asistida por Computador/métodos , Adulto , Humanos , Masculino
19.
Talanta ; 148: 626-32, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26653493

RESUMEN

Spectrophotometric sequential injection system (SI) is proposed to automate the method of simultaneous determination of Fe(II) and Fe(III) on the basis of parameters of a single peak. In the developed SI system, sample and mixture of reagents (1,10-phenanthroline and sulfosalicylic acid) are introduced into a vessel, where in an acid environment (pH≅3) appropriate compounds of Fe(II) and Fe(III) with 1,10-phenanthroline and sulfosalicylic acid are formed, respectively. Then, in turn, air, sample, EDTA and sample again, are introduced into a holding coil. After the flow reversal, a segment of air is removed from the system by an additional valve and as EDTA replaces sulfosalicylic acid forming a more stable colorless compound with Fe(III), a complex signal is registered. Measurements are performed at wavelength 530 nm. The absorbance measured at minimum of the negative peak and the area or the absorbance measured at maximum of the signal can be used as measures corresponding to Fe(II) and Fe(III) concentrations, respectively. The time of the peak registration is about 2 min. Two-component calibration has been applied to analysis. Fe(II) and Fe(III) can be determined within the concentration ranges of 0.04-4.00 and 0.1-5.00 mg L(-1), with precision less than 2.8% and 1.7% (RSD), respectively and accuracy better than 7% (RE). The detection limit is 0.04 and 0.09 mg L(-1) for Fe(II) and Fe(III), respectively. The method was applied to analysis of artesian water samples.

20.
Clin Transl Oncol ; 18(2): 189-95, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26250765

RESUMEN

BACKGROUND: Response to chemotherapy is a prognostic factor in patients with Ewing sarcoma (ES); the role of FDG PET to predict response in these patients has not been thoroughly investigated. We evaluated the diagnostic accuracy and the potential of FDG PET to predict response to chemotherapy (CHT). MATERIALS AND METHODS: We analyzed data of 50 patients with ES (median age 12.6 years). All patients were treated with neoadjuvant CHT, and underwent surgery for local control. All patients had (18)F-FDG PET/CT at diagnosis and after induction CHT, prior to local control. We compared response assessed by histopathology with FDG PET using standard uptake values (SUVs). RESULTS: Median SUV at diagnosis (SUV I) was 5 (range 1.2-17), and median SUV after neoadjuvant chemotherapy (SUV II) was 1.8 (range 0-8.4). Median SUV II/I ratio was 0.3 (range 0-1). SUV at diagnosis was significantly lower in patients with good histological response than in patients with poor histological response (median 3.8 vs. 7.2, p 0.02). We found a significant correlation between SUV II and outcome; the positive predictive value of an SUV II ≤ 2.5 for favorable response was 84.21 %, and the median SUV II was significantly higher in patients with disease progression (2.3 vs. 1.6, p = 0.04). In multivariate analysis, necrosis and SUV II were significant predictors of outcome. CONCLUSIONS: (18)F-FDG PET demonstrates high diagnostic accuracy for response to initial chemotherapy in patients with ES and it correlates with outcome. The role of FDG PET in predicting response and outcome should be further investigated.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Sarcoma de Ewing/diagnóstico por imagen , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Fluorodesoxiglucosa F18 , Humanos , Estimación de Kaplan-Meier , Masculino , Imagen Multimodal , Pronóstico , Modelos de Riesgos Proporcionales , Radiofármacos , Estudios Retrospectivos , Sarcoma de Ewing/tratamiento farmacológico , Sarcoma de Ewing/patología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
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