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1.
J Synchrotron Radiat ; 30(Pt 1): 242-250, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36601943

RESUMEN

The PERCIVAL detector is a CMOS imager designed for the soft X-ray regime at photon sources. Although still in its final development phase, it has recently seen its first user experiments: ptychography at a free-electron laser, holographic imaging at a storage ring and preliminary tests on X-ray photon correlation spectroscopy. The detector performed remarkably well in terms of spatial resolution achievable in the sample plane, owing to its small pixel size, large active area and very large dynamic range; but also in terms of its frame rate, which is significantly faster than traditional CCDs. In particular, it is the combination of these features which makes PERCIVAL an attractive option for soft X-ray science.


Asunto(s)
Fotones , Radiografía , Rayos X
2.
Antimicrob Agents Chemother ; 58(9): 5096-101, 2014 09.
Artículo en Inglés | MEDLINE | ID: mdl-24936595

RESUMEN

Azole-resistant Aspergillus fumigatus harboring the TR34/L98H or TR46/Y121F/T289A alterations is increasingly found in Europe and Asia. Here, we present the first clinical cases of TR46/Y121/T289A and three cases of TR34/L98H outside the cystic fibrosis (CF) population in Denmark and the results of environmental surveys. Four patients (2012 to 2014) with 11 A. fumigatus and 4 Rhizomucor pusillus isolates and 239 soil samples (spring 2010 and autumn 2013, respectively) with a total of 113 A. fumigatus isolates were examined. Aspergillus isolates were screened for azole resistance using azole-containing agar. Confirmatory susceptibility testing was done using the EUCAST microbroth dilution EDEF 9.1 reference method. For relevant A. fumigatus isolates, CYP51A sequencing and microsatellite genotyping were performed. Three patients harbored TR34/L98H isolates. Two were azole naive at the time of acquisition and two were coinfected with wild-type A. fumigatus or R. pusillus isolates, complicating and delaying diagnosis. The TR46/Y121F/T289A strain was isolated in 2014 from a lung transplant patient. Genotyping indicated that susceptible and resistant Aspergillus isolates were unrelated and that no transmission between patients occurred. Azole resistance was not detected in any of the 113 soil isolates. TR34/L98H and TR46/Y121F/T289A alterations appear to be emerging in the clinical setting in Denmark and now involve azole-naive patients. Two recent soil-sampling surveys in Denmark were unable to indicate any increased prevalence of azole-resistant A. fumigatus in the environment. These findings further support the demand for real-time susceptibility testing of all clinically relevant isolates and for studies investigating the seasonal variation and ecological niches for azole-resistant environmental A. fumigatus.


Asunto(s)
Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Azoles/farmacología , Adulto , Anciano , Antifúngicos/farmacología , Aspergilosis/tratamiento farmacológico , Dinamarca , Farmacorresistencia Fúngica/genética , Ambiente , Femenino , Proteínas Fúngicas/genética , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Repeticiones de Microsatélite/genética , Persona de Mediana Edad
3.
Br J Radiol ; 85(1015): e307-13, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22745210

RESUMEN

OBJECTIVES: A contrast-enhanced multidetector CT (MDCT) scan is the first choice examination when evaluating patients with suspected lung cancer. However, while the clinical focus is on CT, research focus is on molecular biological methods whereby radiolabelled pharmaceuticals are injected into participants and target malignant lung tumours. We examined whether a contrast-enhanced MDCT scan supplied with an additional non-contrast enhanced high-resolution CT scan, or a newer but more expensive (99m)Tc depreotide single photon emission CT (SPECT) scan, was the better first-choice examination for the work-up of pulmonary lesions. Furthermore, we examined whether a (99m)Tc depreotide SPECT scan was an appropriate second-choice examination for patients with indeterminate lesions. METHODS: 140 participants were included in the analysis. CT images were given a malignancy potential rating of 1, 2 or 3 with higher rating being indicative of disease. (99m)Tc depreotide SPECT images were graded either positive or negative. Histopathology and CT follow-up were used as reference standard. Sensitivity, specificity and diagnostic accuracy were calculated. RESULTS: Overall sensitivity, specificity and diagnostic accuracy of CT were 97%, 30% and 84%, respectively. Overall sensitivity, specificity and diagnostic accuracy of (99m)Tc depreotide SPECT were 94%, 58% and 76%, respectively. For indeterminate lesions sensitivity, specificity and diagnostic accuracy of (99m)Tc depreotide SPECT were 71%, 68% and 69%, respectively. CONCLUSION: Both CT and (99m)Tc depreotide SPECT made valuable contributions to the evaluation of pulmonary lesions. (99m)Tc depreotide SPECT results were not superior to CT results and did not contribute further to the diagnostic work-up. Regarding indeterminate lesions,( 99m)Tc depreotide SPECT sensitivity was too low.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Compuestos de Organotecnecio , Nódulo Pulmonar Solitario/diagnóstico por imagen , Somatostatina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Intervalos de Confianza , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Enfermedades Pulmonares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Estudios Prospectivos , Curva ROC , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión de Fotón Único/métodos
4.
Euro Surveill ; 11(12): 229-33, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17370966

RESUMEN

Early detection of disease outbreaks is essential for authorities to initiate and conduct an appropriate response. A need for an outbreak detection that monitored data predating laboratory confirmations was identified, which prompted the establishment of a novel symptom surveillance system. The surveillance system monitors approximately 80% of the Danish population by applying an outbreak detection algorithm to ambulance dispatch data. The system also monitors both regional and national activity and has a built-in, switch-on capacity for implementing symptom surveillance reporting in case of an alert. In an evaluation with outbreak scenarios it was found that decreasing the outbreak detection sensitivity from a prediction limit of 95% to one of 99% moderately reduced the time to detection, but considerably diminished the number of false alerts. The system was able to detect an increased activity of influenza-like illness in December 2003 in a timely fashion. The system has now been implemented in the national disease surveillance programme.


Asunto(s)
Sistemas de Comunicación entre Servicios de Urgencia/tendencias , Vigilancia de Guardia , Ambulancias , Dinamarca/epidemiología , Brotes de Enfermedades/prevención & control , Humanos , Factores de Tiempo
5.
Phys Rev Lett ; 94(5): 053002, 2005 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-15783634

RESUMEN

We have measured the near-infrared absorption spectrum for isolated C60- ions at room temperature. Two bands, at 9145 cm(-1) and 10460 cm(-1), have been identified in addition to the main absorption band at 9382 cm(-1), seen also at low temperature in a matrix. An interpretation based on the theory of dynamic Jahn-Teller effects is proposed.

6.
Phys Rev Lett ; 91(4): 048302, 2003 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-12906699

RESUMEN

The lifetimes of both deprotonated adenosine 5(')-monophosphate (AMP) and protonated AMP, after 266-nm photon absorption and intramolecular vibrational redistribution, were determined to be 16 micros based on a newly developed heavy-ion storage ring technique. Protonation of the adenine nucleobase seriously affects the fragmentation mechanism: the major part of the photoexcited anions fragment in a statistical (ergodic) process, whereas nearly all the cations (>99%) fragment in a nonergodic process. In solution at natural pH the AMP anion is prevalent and photoproduct formation is therefore less important as the time for vibrational cooling is of the order of picoseconds.


Asunto(s)
Adenosina Monofosfato/química , Concentración de Iones de Hidrógeno , Modelos Químicos , Fotoquímica , Protones , Termodinámica , Vacio
7.
Phys Rev Lett ; 90(11): 118103, 2003 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-12688970

RESUMEN

Photoabsorption studies of red fluorescent protein chromophore anions have been performed at the ELISA electrostatic heavy-ion storage ring. The broad absorption band due to electronic excitation of the chromophores is tuned to a longer wavelength (redshifted) by extending the electronic conjugation of the molecule. A clear vibrational progression is resolved with E(vib) approximately 380 and 520 cm(-1) for two different forms of the chromophore. The vibrational modes correspond to collective motions of the entire molecular structure. It is argued that the excited electronic state has an equilibrium configuration far from that of the electronic ground state, i.e., poor Franck Condon overlap.


Asunto(s)
Proteínas Luminiscentes/química , Absorción , Aniones , Fotoquímica , Espectrofotometría/métodos , Electricidad Estática , Proteína Fluorescente Roja
8.
Phys Rev Lett ; 87(22): 228102, 2001 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-11736429

RESUMEN

A sensitive photoabsorption technique for studies of gas-phase biomolecules has been used at the ELISA electrostatic heavy-ion storage ring. We show that the anion form of the chromophore of the green fluorescent protein in vacuo has an absorption maximum at 479 nm, which coincides with one of the two absorption peaks of the protein. Its absorption characteristics are therefore ascribed to intrinsic chemical properties of the chromophore. Evidently, the special beta-can structure of the protein provides shielding of the chromophore from the surroundings without significantly changing the electronic structure of the chromophore through interactions with amino acid side chains.


Asunto(s)
Proteínas Luminiscentes/química , Aniones , Ensayo de Inmunoadsorción Enzimática , Gases , Proteínas Fluorescentes Verdes , Espectrofotometría Ultravioleta , Electricidad Estática , Vacio
9.
Phys Rev Lett ; 87(12): 123401, 2001 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-11580509

RESUMEN

The exponential law is valid both for decay from a single quantum state into a continuum and for an ensemble maintained in thermal equilibrium. For statistical decay of an ensemble of isolated systems with a broad energy distribution, the exponential decay is replaced by a 1/t distribution. We present confirmation of this decay law by experiments with cluster anions in a small electrostatic storage ring. Deviations from the 1/t law for such an ensemble give important information on the dynamics of the systems. As examples, we present measurements revealing strong radiative cooling of anions of both metal clusters and fullerenes.

10.
Phys Rev Lett ; 87(7): 073401, 2001 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-11497890

RESUMEN

We have stored positively charged fullerene ions C(+)(n) (n even, from 48 to 70 and 76), C(2+)(60) and C(2+)(70) in an electrostatic storage ring and have measured the rate of emission of neutral fragments as a function of time. In the time range of the measurements, 50 micros to a few milliseconds, the rate decreases strongly due to radiative cooling of the molecules. Using the cooling rate predicted from a dielectric model, we have extracted the dissociation energies for C(2) loss from the measurements. As expected, the energies are largest for the "magic" fullerenes, C(50), C(60), and C(70), and the value of 9.8+/-0.1 eV for C(2) loss from C(+)(60) is in reasonable agreement with theory and with other recent experiments.

11.
Acta Oncol ; 40(7): 796-800, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11859977

RESUMEN

Two treatment options are widely used for the cure of T1 glottic squamous cell carcinoma: radiotherapy and surgical removal. There is ongoing controversy about whether laser excision should be offered to patients with T1 glottic carcinoma. The purpose of this study is to present a review of studies dealing with treatment outcome after laser excision of T1 glottic carcinoma. Eighteen original papers on outcomes were identified. Recurrence rates ranged from 4% to 35%. The disease-specific survival rate at 5 years was found to be from 89% to 100% and crude survival from 74% to 100%. Of the six studies dealing with voice quality, radiation therapy was found to be more effective in preservation of the voice in three, while in the other three studies, no significant difference could be detected. With respect to costs of treatment, in three out of four studies laser surgery was found to be the more economical treatment option. Laser surgery seems to provide comparably low recurrence rates and high disease-specific survival as compared with radiotherapy. In T1 cancer, laser resection leaves the patient with a poorer voice quality than is the case with radiation therapy, but laser treatment seems to be the cheaper option.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias Laríngeas/cirugía , Terapia por Láser , Recurrencia Local de Neoplasia , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Humanos , Neoplasias Laríngeas/patología , Radioterapia Adyuvante , Terapia Recuperativa , Resultado del Tratamiento
12.
Phys Rev Lett ; 85(19): 4028-31, 2000 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-11056616

RESUMEN

The shape parameters for the lowest-lying (1)P(o) resonance, (2)¿0¿-3, of D- have been measured using high-resolution vacuum-ultraviolet spectroscopy. The experiment was performed at the storage ring ASTRID, and the resonance was resolved by applying electron cooling to reduce the velocity spread of the ion beam. The resonance has a width of 37(3) microeV while the asymmetry parameter q of the Fano profile is -16(3). These values present the first critical test of a large number of theoretical calculations.

16.
Environ Monit Assess ; 43(1): 11-7, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24193730

RESUMEN

Environmental indicators for long-range atmospheric transported heavy metals have been developed. The indicators are based on data for Pb and Cd from national moss surveys which are performed regularly in Norway. The interpolation programme 'kriging' has been used to transform the data from irregular grids to regular grids. Contour maps have been produced, and areas above estimated background levels for Pb and Cd in mosses have been calculated. The indicators are used to characterise the atmospheric deposition of long-range atmospheric transported heavy metals and monitor the changes with time.

17.
J Neurochem ; 65(3): 1325-31, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7643110

RESUMEN

To assess the importance of the cysteine residues Cys347 and Cys351 in the carboxylic tail in the human D1 dopamine receptor, seven mutant receptors were constructed by PCR. The pharmacological and functional properties of the wild-type and mutant receptors were assessed following transient expression in COS-7 cells. Affinities for [3H]SCH 23390 of mutant S347 (Cys347-->Gly), T348 (Tyr348-->stop), S351 (Cys351-->Gly), T351 (Cys351-->stop), T352 (Pro352-->stop), and S347/S351 (Cys347-->Gly and Cys351-->Gly) were similar to that of wild-type receptor, whereas the expression levels were reduced up to 80%. The potency of dopaminergic antagonists for these mutant receptors was very similar to that of the wild-type receptor. However, mutant T347 (Cys347-->stop) showed a 15-25-fold reduced affinity for the antagonists SCH 23390, (+)-butaclamol, and cis-flupentixol, thus not allowing radioligand analysis. Wild-type and mutant receptors responded dose-dependently with similar potency to dopamine and SKF 38393 with an increased adenylyl cyclase activity. However, mutant receptors with the Cys347 residue changed or removed displayed a diminished ability to activate adenylyl cyclase. Dopamine preexposure desensitized wild-type and mutant S351 receptors. However, mutant receptors with Cys347 replaced or the distal part of the carboxyl tail removed were unable to desensitize. Thus, Cys347 in the cytoplasmic tail of the human D1 dopamine receptor is important for the receptor in maintaining the conformation for antagonist binding, to play a crucial role in activation of adenylyl cyclase, and to be essential for agonist-induced desensitization.


Asunto(s)
Cisteína , Receptores de Dopamina D1/química , Receptores de Dopamina D1/fisiología , Adenilil Ciclasas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Benzazepinas/metabolismo , Línea Celular , Antagonistas de Dopamina/farmacología , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Ensayo de Unión Radioligante , Receptores de Dopamina D1/genética , Relación Estructura-Actividad , Transfección
20.
Eur J Pharmacol ; 267(1): 85-93, 1994 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8206133

RESUMEN

Human dopamine D1a and D1b receptors were stably expressed in Baby Hamster Kidney (BHK) or Chinese Hamster Ovary (CHO) cells. [3H]SCH23390 saturation experiments indicated the presence of only a single binding site in the D1a expressing cell line with a Kd of 0.5 nM. In D1b expressing cell lines, two binding sites were observed with Kd values of 0.5 and 5 nM in CHO cells and 0.05 and 1.6 nM in BHK cells, respectively. Neither of the receptors affected Ca2+ metabolism whereas they both were coupled in a stimulatory fashion to adenylyl cyclase. The pharmacological profile of both the D1a and D1b receptors as assessed from inhibition of specific [3H]SCH 23390 binding was classical D1-like. Thus, benzazepine derivatives as well as the atypical neuroleptics, clozapine and fluperlapine, exhibited high affinity whereas D2 selective compounds like sulpiride and spiperone had low affinity for these receptors. Besides SCH 23390, only NNC 112, fluphenazine and bulbocapnine were able to discriminate between the two states of the D1b receptor. In case of the D1a receptor, the Ki values obtained in binding experiments were very similar to Ki values obtained from inhibition of dopamine stimulated adenylyl cyclase. In the D1b expressing cell line, the Ki values obtained from inhibition of the dopamine stimulated adenylyl cyclase indicated a significantly better correlation with the state of the D1b receptor showing high affinity for antagonists. In agreement with observations from binding experiments, dopamine was around 20 fold more potent in stimulating adenylyl cyclase via the D1b receptor as compared to the D1a receptor.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Receptores de Dopamina D1/fisiología , Adenilil Ciclasas/análisis , Animales , Benzazepinas/metabolismo , Células CHO , Calcio/análisis , Membrana Celular/efectos de los fármacos , Células Cultivadas , Cricetinae , AMP Cíclico/análisis , Humanos , Riñón/citología , Receptores de Dopamina D1/antagonistas & inhibidores , Sistemas de Mensajero Secundario
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