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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.
Phys Rev Lett ; 113(6): 064801, 2014 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-25148330

RESUMEN

We report on measurements of second-order intensity correlations at the high-brilliance storage ring PETRA III using a prototype of the newly developed adaptive gain integrating pixel detector. The detector records individual synchrotron radiation pulses with an x-ray photon energy of 14.4 keV and repetition rate of about 5 MHz. The second-order intensity correlation function is measured simultaneously at different spatial separations, which allows us to determine the transverse coherence length at these x-ray energies. The measured values are in a good agreement with theoretical simulations based on the Gaussian Schell model.

3.
Genes Immun ; 10(1): 15-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18946483

RESUMEN

Variation within intron 19 of the CLEC16A (KIAA0350) gene region was recently found to be unequivocally associated with type 1 diabetes (T1D) in genome-wide association (GWA) studies in Northern European populations. A variant in intron 22 that is nearly independent of the intron 19 variant showed suggestive evidence of association with multiple sclerosis (MS). Here, we genotyped the rs725613 polymorphism, representative of the earlier reported associations with T1D within CLEC16A, in 1037 T1D cases, 1498 MS cases and 1706 matched controls, all from the founder, autoimmunity-prone Sardinian population. In these Sardinian samples, allele A of rs725613 is positively associated not only with T1D (odds ratio=1.15, P one-tail=5.1 x 10(-3)) but also, and with a comparable effect size, with MS (odds ratio=1.21, P one-tail 6.7 x 10(-5)). Taken together these data provide evidence of joint disease association in T1D and MS within CLEC16A and underline a shared disease pathway.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Variación Genética , Estudio de Asociación del Genoma Completo , Lectinas Tipo C/genética , Proteínas de Transporte de Monosacáridos/genética , Esclerosis Múltiple/genética , Adulto , Edad de Inicio , Alelos , Estudios de Casos y Controles , Familia , Femenino , Humanos , Italia , Masculino , Oportunidad Relativa , Polimorfismo Genético , Probabilidad
4.
Parassitologia ; 49(4): 235-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18689234

RESUMEN

In order to better understand the epidemiology of ovine toxoplasmosis in Sardinia, a serological survey was carried out on 22 flocks with no fertility problems. In total 1043 sera (9% of the 11,382 sheep raised in the flocks) were examined by means of a commercial ELISA kit. To verify the performance of ELISA test, 160 selected sera were tested again with a gold standard test (IFAT). Performance of the commercial ELISA kit was summarised in terms of Sensitivity (SE), Specificity (SP), positive and negative Likelihood Ratios (LR+; LR-). The overall seroprevalence with ELISA test was recorded as 51.3%. It was generally increasing according to age and was significantly lower in animals younger than one year (with the exception of < 1 month old lambs). This survey provided data on the current Toxoplasma gondii sheep seroprevalence in Sardinia, confirmed a still high parasite pressure and pointed out that consumption of raw or undercooked ovine meat can be considered a potential risk factor for humans.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedades de las Ovejas/epidemiología , Toxoplasma/inmunología , Toxoplasmosis Animal/epidemiología , Factores de Edad , Animales , Reservorios de Enfermedades , Ensayo de Inmunoadsorción Enzimática , Femenino , Italia/epidemiología , Sensibilidad y Especificidad , Estudios Seroepidemiológicos , Ovinos/sangre , Ovinos/parasitología
5.
J Pharm Biomed Anal ; 37(1): 65-71, 2005 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-15664744

RESUMEN

A systematic analysis of the influence of different proportions of excipients on the stability of a solid dosage form was carried out. In particular, a d-optimal mixture experimental design was applied for the evaluation of glibenclamide compatibility in tablet formulations, consisting of four classic excipients (natrosol as binding agent, stearic acid as lubricant, sorbitol as diluent and cross-linked polyvinylpyrrolidone as disintegrant). The goal was to find the mixture component proportions which correspond to the optimal drug melting parameters, i.e. its maximum stability, using differential scanning calorimetry (DSC) to quickly obtain information about possible interactions among the formulation components. The absolute value of the difference between the melting peak temperature of pure drug endotherm and that in each analysed mixture and the absolute value of the difference between the enthalpy of the pure glibenclamide melting peak and that of its melting peak in the different analyzed mixtures, were chosen as indexes of the drug-excipient interaction degree.


Asunto(s)
Gliburida/análisis , Gliburida/química , Proyectos de Investigación , Rastreo Diferencial de Calorimetría/métodos , Interacciones Farmacológicas , Estereoisomerismo , Comprimidos Recubiertos
6.
Am J Med Genet ; 86(3): 294-9, 1999 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-10482884

RESUMEN

We report on two Italian brothers with facial clefting, hypertelorism, urogenital anomalies including micropenis, shawl scrotum, hearing loss, caudal appendage, and umbilical hernia. We have evaluated the two cases as Malpuech syndrome. This is an extremely rare autosomal recessive syndrome.


Asunto(s)
Anomalías Múltiples/genética , Niño , Labio Leporino/genética , Fisura del Paladar/genética , Sordera/genética , Genes Recesivos , Hernia Umbilical/genética , Humanos , Hipertelorismo/genética , Discapacidad Intelectual/genética , Masculino , Síndrome , Anomalías Urogenitales/genética
7.
J Chromatogr A ; 1032(1-2): 253-63, 2004 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-15065803

RESUMEN

A simple, fast and selective micellar electrokinetic chromatographic (MEKC) method for the simultaneous assay of ketorolac tromethamine and its known related impurities (1-hydroxy analog of ketorolac, 1-keto analog of ketorolac and decarboxylated ketorolac), in both drug substance and coated tablets, is described. The compounds were detected at 323 nm, and flufenamic acid (FL) and tolmetin (TL) were chosen as internal standards to quantify ketorolac tromethamine and impurities, respectively. The multivariate optimization of the experimental conditions was carried out by means of the response surface study, considering as responses the resolution values and analysis time. The optimized background electrolyte (BGE) consisted of a mixture of 13 mM boric acid and phosphoric acid, adjusted to pH 9.1 with 1 M sodium hydroxide, containing 73 mM sodium dodecyl sulfate (SDS). Optimal temperature and voltage were 30 degrees C and 27 kV. Applying these conditions, all compounds were resolved in about 6 min. The related substances could be quantified up to the 0.1% (w/w) level. Validation was performed, either for drug substances and drug product, evaluating selectivity, robustness, linearity and range, precision, accuracy, detection and quantitation limits and system suitability.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Cromatografía Capilar Electrocinética Micelar/métodos , Ketorolaco Trometamina/análisis , Calibración , Análisis Multivariante , Sensibilidad y Especificidad
8.
J Biomech ; 34(6): 821-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11470122

RESUMEN

A new device for the assessment of instantaneous angular and linear accelerations of the head is presented, which is based on four linear tri-axial accelerometers suitably attached to the head by an helmet. A procedure for reproducible helmet placement and calibration is given. A method is also illustrated to work out the different linear accelerations sensed by the vestibular organs in the left and right labyrinths and the components of the angular acceleration sensed by their semicircular canals. The computation is based on few individual parameters describing the helmet position with respect to external landmarks and on the average internal position and orientation of the vestibula. The purpose is to study the components of internal inertial forces, which represent the primary inputs to the vestibular system devoted to equilibrium and oculomotor control. The system is designed to be of easy application during rehabilitation exercises and in clinical environment during diagnostic and therapeutic manoeuvres. The prototype is tested with simple free movements such as "yes", "no", and gait.


Asunto(s)
Aceleración , Gravitación , Vestíbulo del Laberinto/fisiología , Fenómenos Biomecánicos , Humanos , Modelos Biológicos , Movimiento/fisiología , Canales Semicirculares/fisiología
9.
Clin Dysmorphol ; 9(2): 103-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10826620

RESUMEN

We report two patients, one with sternal cleft, haemangiomas, supraumbilical midline raphe and the other with a sternal cleft, haemangiomas, coarctation of the aorta with a right aortic arch.


Asunto(s)
Anomalías Múltiples/patología , Aorta Abdominal/anomalías , Coartación Aórtica/patología , Hemangioma/patología , Esternón/anomalías , Femenino , Hemangioma/congénito , Humanos , Recién Nacido , Ombligo/anomalías
10.
Pediatr Med Chir ; 6(6): 839-42, 1984.
Artículo en Italiano | MEDLINE | ID: mdl-6545599

RESUMEN

A new case of pyloric atresia associated with epidermolysis bullosa was observed. To our knowledge seventeen other cases of this condition have been previously reported, five of these also presented aplasia cutis congenita. Although there is no clear agreement as to which type of epidermolysis is associated, junctional bullous epidermatosis is the most commonly reported form. This is unlikely to be a chance association, since both are extremely rare and autosomal recessive hereditary conditions. Some authors have proposed a pleiotropic effect of a single gene or autosomal recessive, with close gene linkage, inheritance of these two conditions. After careful consideration of the various pathogenetic hypotheses, we conclude that epidermolysis, even when non in the scarring form, may be responsible for pyloric atresia.


Asunto(s)
Epidermólisis Ampollosa/complicaciones , Píloro/anomalías , Displasia Ectodérmica/complicaciones , Femenino , Humanos , Recién Nacido
11.
Biomed Res Int ; 2014: 862372, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24822218

RESUMEN

In the last thirty years, steady progress in the diagnostic tools and care of subjects affected by congenital heart diseases (CHD) has resulted in a significant increase in their survival to adulthood, even for those affected by complex CHD. Based on these premises, a number of teenagers and adults affected by corrected (surgically or through interventional techniques) CHD ask to be allowed to undertake sporting activities, both at a recreational and competitive level. The purpose of this review is to examine the mechanisms influencing the adaptation at physical exercise of patients suffering from complex CHD. The conclusion is that even if there are some modest risks with exercise, they should be seen in perspective, and the life-long benefits of regular exercise on general health, mood, and well-being should be emphasized.


Asunto(s)
Adaptación Fisiológica/fisiología , Ejercicio Físico/fisiología , Cardiopatías Congénitas , Adolescente , Adulto , Niño , Femenino , Cardiopatías Congénitas/rehabilitación , Cardiopatías Congénitas/cirugía , Humanos , Masculino , Persona de Mediana Edad
13.
Artículo en Inglés | MEDLINE | ID: mdl-2853923

RESUMEN

95 eyes of patients with bilateral exfoliation syndrome (ES) were examined with fluoroangiography. The visual field and the intraocular pressure were tested in the same eyes. The relationship between visual field defects, fluoroangiographic changes of the optic disk and intraocular hypertension is discussed. The results show that when hypertension and defects of perfusion are present in the same eye the visual field defect is always present and it is more severe.


Asunto(s)
Segmento Anterior del Ojo , Oftalmopatías/patología , Presión Intraocular , Hipertensión Ocular/complicaciones , Disco Óptico/irrigación sanguínea , Campos Visuales , Angiografía con Fluoresceína , Humanos , Enfermedades del Cristalino/patología , Síndrome
14.
Acta Ophthalmol Suppl (1985) ; 184: 66-70, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2853924

RESUMEN

Patients with monolateral exfoliation syndrome were examined to elucidate the differences between the eye with the exfoliation and the fellow eye and to explain the damage of the visual field of the eyes with or without exfoliation. The greatest difference between the two groups of eyes is represented by an increased pigmentation of the anterior chamber angle. The visual field, as in bilateral cases, shows the greatest damage when exfoliation and hypertension are present together in the same eye. An hypothesis is put forward to explain the supposed mechanism of action of these two factors.


Asunto(s)
Segmento Anterior del Ojo , Oftalmopatías/patología , Campos Visuales , Anciano , Cámara Anterior/patología , Oftalmopatías/complicaciones , Femenino , Angiografía con Fluoresceína , Humanos , Enfermedades del Cristalino/complicaciones , Masculino , Hipertensión Ocular/complicaciones , Tonometría Ocular
15.
Planta ; 211(3): 384-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10987557

RESUMEN

A simple procedure is described for the fabrication of micrometer to nanometer-scale platinum electrodes to be used in a vibrating oxygen-selective system. The electrode was prepared by etching a fine platinum wire and insulating it with an electrophoretic paint. The dimensions allowed this electrode to be used with the "vibrating probe technique" in exploratory studies aimed at mapping and measuring the patterns of net influxes as well as effluxes of oxygen in Olea europaea L. leaves and roots with spatial and temporal resolutions of a few microns and a few seconds, respectively. The magnitude and spatial localisation of O2 influxes in roots was characterised by two distinct peaks. The first, in the division zone, averaged 38 +/- 5 nmol m(-2) s(-1); the second, in the elongation region, averaged 68 +/- 6 nmol m(-2) s(-1). Long-term records of oxygen influx in the elongation region of the root showed an oscillatory regime characterised by a fast oscillation with periods of about 8-9 min. In leaves, the system allowed the measurement of real-time changes in O2 evolution following changes in light. Furthermore, it was possible to obtain "topographical" images of the photosynthetically generated oxygen diffusing through different stomata from a region of the leaf of 120 microm x 120 microm. The combination of topographic and electrochemical information at the micrometer scale makes the system an efficient tool for studying biological phenomena involving oxygen diffusion.


Asunto(s)
Oxígeno/metabolismo , Plantas Comestibles/fisiología , Cinética , Luz , Potenciales de la Membrana , Microelectrodos , Hojas de la Planta/metabolismo , Brotes de la Planta/metabolismo , Polarografía/métodos , Factores de Tiempo , Árboles/fisiología
16.
Pathologica ; 91(3): 198-202, 1999 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-10536466

RESUMEN

INTRODUCTION: Rhabdoid tumour of the kidney is a new independent entity. Before it was considered a variant of Wilms tumor of the kidney. Now we have enough parametres to define the rhabdoid tumor: immunohistochemistry positive by the vimentin, special histological features and behaviour. CASE: We report a very aggressive case of rhabdoid tumor found in a two week old infant. RESULTS: We studied aspects of histology and histochemistry. We found a positivity for vimentin and many cells in apoptosis. DISCUSSION: The mild positivity for vimentin and the high number of cells in apoptosis suggest a relationship between apoptosis and behaviour.


Asunto(s)
Neoplasias Renales/congénito , Tumor Rabdoide/congénito , Apoptosis , Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/congénito , Neoplasias Encefálicas/secundario , Progresión de la Enfermedad , Resultado Fatal , Femenino , Neoplasias Cardíacas/congénito , Neoplasias Cardíacas/secundario , Humanos , Recién Nacido , Neoplasias Renales/química , Neoplasias Renales/ultraestructura , Neoplasias Hepáticas/congénito , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/congénito , Neoplasias Pulmonares/secundario , Metástasis Linfática , Proteínas de Neoplasias/análisis , Tumor Rabdoide/química , Tumor Rabdoide/secundario , Tumor Rabdoide/ultraestructura , Vimentina/análisis
17.
G Ital Cardiol ; 17(8): 667-72, 1987 Aug.
Artículo en Italiano | MEDLINE | ID: mdl-3692071

RESUMEN

Tricuspid regurgitation (TR) is detected by Doppler echocardiography in a high proportion of patients with right ventricle pressure or volume overload. Continuous wave Doppler (CW) provides a noninvasive estimation of the transtricuspid systolic pressure gradient, applying the modified Bernoulli formula to the maximum velocity of the TR jet. The purpose of this study was to test the accuracy of the CW prediction of systolic right ventricular pressure (RVPs), obtained adding a clinical estimate of the mean right atrial pressure (RAPm) to the Doppler derived pressure gradient. The study population consisted of 22 adult patients with Doppler proved TR, undergoing right heart catheterization (cath) for mitral valve disease (12 pts), atrial septal defect (8 pts), dilated cardiomyopathy (1 pt) or pulmonary hypertension (1 pt). Two studies were duplicated after nifedipine administration. TR was graded by pulsed Doppler flow mapping as mild in 7, moderate in 11, severe in 4 pts. RAPm was estimated clinically from the inspection of neck veins pulsatility (mmHg = pulsatility cm+5/1.3). At CATH RVPs ranged from 27 to 80 (46 +/- 17) mmHg, RAPm from 0 to 13 (6 +/- 3) mmHg. RVPs Doppler prediction showed a close correlation with CATH (r .97, SEE 4.2 mmHg), with a slight mean underestimation (-2 +/- 4 mmHg) (Fig. 3, Tab. I). The discrepancies between CW and CATH ranged from -9 to +10 mmHg, almost entirely due to inaccuracy of the RAPm clinical estimate (r .48, see 3.8 mmHg) (Fig. 4, Tab. I).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Presión Sanguínea , Ecocardiografía/métodos , Insuficiencia de la Válvula Tricúspide/fisiopatología , Adolescente , Adulto , Anciano , Cateterismo Cardíaco , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sístole
18.
Pediatr Res ; 20(11): 1077-81, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3797101

RESUMEN

In this study we have carried out alpha-globin gene mapping, hemoglobin (Hb) Bart's quantitation serum bilirubin, and red blood cell indices determination in a group of Sardinian appropriate for gestational age premature infants (from 32 to 35 wk gestation) in order to define the incidence in this population of the different alpha-thalassemia syndromes, their expression rate, and the correlation between the alpha-globin genotype and phenotype at this developmental stage. The gene frequencies of deletion (-alpha) and nondeletion (alpha alpha th) alpha-thalassemia were 0.29 and 0.04, respectively, and thus not different from those found in full-term newborns from the same population. The majority of premature newborns with a single alpha-globin gene deletion [(-alpha/alpha alpha) genotype] were hematologically silent. Those who manifested increased Hb Bart's (1.2 to 3.4%) had slightly reduced Hb levels (17.4 +/- 2.6 g/dl), mean corpuscular volume (102.6 +/- 6.3 fl), and mean corpuscular Hb (34.8 +/- 2.0 pg) values. Those infants with the deletion of two alpha-globin structural genes (-alpha/-alpha) showed without exception moderate amount of Hb Bart's in the 3.5-8.1% range and an obvious decrease of Hb levels (16.1 +/- 1.6 g/dl) mean corpuscular Hb (30.6 +/- 3.5 pg), and mean corpuscular volume (88.5 +/- 11.5 fl) values. The only infant with the deletion of 3 alpha-globin structural genes had 25% Hb Bart's associated with a moderate microcytic anemia at birth and developed the clinical picture of Hb H disease. Carriers of nondeletion alpha-thalassemia (alpha alpha/alpha alpha th) showed variable amount of Hb Bart's always associated with thalassemia-like red cell indices.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Enfermedades del Prematuro/genética , Talasemia/genética , Mapeo Cromosómico , Índices de Eritrocitos , Genotipo , Globinas/análisis , Humanos , Recién Nacido , Enfermedades del Prematuro/sangre , Estudios Longitudinales , Fenotipo , Talasemia/sangre
19.
J Pediatr Gastroenterol Nutr ; 23(2): 125-9, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8856577

RESUMEN

The newborn liver is a proven model for the study of liver storage of copper and iron. We analyzed zinc concentration and distribution in the livers of newborns and infants using a systematic tissue-sampling technique. We studied 14 newborns of 26-41 weeks of gestation (WG). One stillborn, and three infants (52-90 days old). At autopsy, a longitudinal liver slice extending from the right to the left lobe was subdivided into 10 samples that were analyzed for zinc concentration by atomic absorption spectroscopy. The mean zinc concentration in the newborn liver was 639 micrograms/g of dry tissue (dt). A striking interindividual variability in zinc liver stores was observed; the hepatic concentration of the metal ranged from 300 to 1,400 micrograms/g dt. We found a correlation between zinc liver content and gestational age. In newborns of 27-32 WG, the hepatic zinc concentration was significantly higher (p < 0.01) than in newborns of 34-41 WG. Zinc stores decreased in the postnatal period; in the infant group, the mean liver zinc concentration was 148 micrograms/g dt. The analysis of zinc concentration in 10 blocks from each liver revealed a regular distribution of the metal, without significant differences between liver lobes. Our data show that the newborn liver can be considered an interesting model for the study of zinc storage, which appears to correlate inversely with gestational age. From a practical point of view, the observed regular distribution of zinc implies that, at least in this model, zinc content determined in a small liver sample is representative of zinc content in the whole liver.


Asunto(s)
Recién Nacido/metabolismo , Hígado/metabolismo , Zinc/farmacocinética , Femenino , Muerte Fetal/metabolismo , Edad Gestacional , Humanos , Lactante , Masculino , Distribución Tisular
20.
Liver ; 14(4): 193-9, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7968279

RESUMEN

Recent observations on a correlation between fetal serum ferritin and gestational age, consistent with an increase in fetal iron stores during pregnancy, led us to study liver iron content in 22 human stillborns, newborns and infants of different gestational and postnatal age. At autopsy, a longitudinal liver slice was subdivided into ten blocks. Each sample was analyzed for iron content by atomic absorption spectroscopy. The mean iron concentration in the studied livers was 21.6 microM/g dry tissue (d.t.). A striking interindividual variability in iron content was observed: the hepatic concentration of the metal ranged from 3.3 to 64.4 microM/g d.t. No correlation was found between the hepatic iron concentration and gestational age or other clinical parameters of the patients studied. Moreover, the total storage iron of the liver did not appear to be correlated with the gestational age. The analysis of iron concentration in ten blocks in each liver revealed an irregular distribution of the metal. Lobar differences were observed, with a tendency of the left lobe to accumulate more iron than the right one. Furthermore, striking differences in iron content were found between adjacent liver samples, ranging in one instance from 4.5 up to 109.0 microM/g of dry tissue. Perls' stain for iron was positive in 7 out of the 22 livers examined, showing an irregular acinar distribution, with preferential periportal localization. Our data show that the newborn liver can be considered an interesting model for the study of iron storage.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Hierro/análisis , Hígado/química , Femenino , Muerte Fetal , Feto/química , Edad Gestacional , Humanos , Recién Nacido , Masculino , Espectrofotometría Atómica
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