Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Phys Rev D ; 99(10)2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-31535060

RESUMEN

Indirect searches for dark matter through Standard Model products of its annihilation generally assume a cross-section which is dominated by a term independent of velocity (s-wave annihilation). However, in many DM models an s-wave annihilation cross-section is absent or helicity suppressed. To reproduce the correct DM relic density in these models, the leading term in the cross section is proportional to the DM velocity squared (p-wave annihilation). Indirect detection of such p-wave DM is difficult because the average velocities of DM in galaxies today are orders of magnitude slower than the DM velocity at the time of decoupling from the primordial thermal plasma, thus suppressing the annihilation cross-section today by some five orders of magnitude relative to its value at freeze out. Thus p-wave DM is out of reach of traditional searches for DM annihilations in the Galactic halo. Near the region of influence of a central supermassive black hole, such as Sgr A*, however, DM can form a localized over-density known as a "spike". In such spikes the DM is predicted to be both concentrated in space and accelerated to higher velocities, thereby allowing the γ-ray signature from its annihilation to potentially be detectable above the background. We use the Fermi Large Area Telescope to search for the γ-ray signature of p-wave annihilating DM from a spike around Sgr A* in the energy range 10 GeV-600 GeV. Such a signal would appear as a point source and would have a sharp line or box-like spectral features difficult to mimic with standard astrophysical processes, indicating a DM origin. We find no significant excess of γ rays in this range, and we place upper limits on the flux in γ-ray boxes originating from the Galactic Center. This result, the first of its kind, is interpreted in the context of different models of the DM density near Sgr A*.

3.
J Chem Phys ; 146(3): 034703, 2017 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-28109242

RESUMEN

Colloidal magnetic nanoparticles (MNPs) based on a nearly monodisperse iron oxide core and capped by oleic acid have been used as model systems for investigating the superparamagnetic spin dynamics by means of magnetometry measurements and nuclear magnetic resonance (1H NMR) relaxometry. The key magnetic properties (saturation magnetization, coercive field, and frequency dependent "blocking" temperature) of MNPs with different core size (3.5 nm, 8.5 nm, and 17.5 nm), shape (spherical and cubic), and dispersant (hexane and water-based formulation) have been determined. 1H NMR dispersion profiles obtained by measuring the r1 (longitudinal) and r2 (transverse) nuclear relaxivities in the frequency range 0.01-60 MHz confirmed that in all samples the physical mechanisms that drive the nuclear relaxation are the Néel reversal at low temperature and the Curie relaxation at high frequency. The magnetization reversal time at room temperature extracted from the fitting of NMR data falls in the typical range of superparamagnetic systems (10-9-10-10 s). Furthermore, from the distance of minimum approach we could conclude that water molecules do not arrive in close vicinity of the magnetic core. Our findings contribute to elucidate the local spin dynamics mechanisms in colloidal superparamagnetic nanoparticles which are useful in biomedical application as, e.g., contrast agents for magnetic resonance imaging.

4.
Clin Ter ; 164(5): e377-9, 2013.
Artículo en Italiano | MEDLINE | ID: mdl-24217838

RESUMEN

Liquid injectable silicone has been used to increase volume in determined cutaneous districts, particularly in aesthetical reconstructive surgery. Although considered biologically inert for a long time this substance produced various complications as granulomatous foreign body reaction (siliconomas), secondary limphedema, tissue destruction and lethal embolism. A 35-year-old Caucasian woman came to our department with erithema and edema on the right leg, fever and chills. A thorough examination of the patient's history revealed injection of liquid silicone 7 years before for cosmetic volume increase of both legs. A closer observation revealed a small fistulous element from which came out white-yellow puruloid material. Antibiotic therapy and drainage of the abscess were undertaken. Within few days of treatment erithema and swelling essentially improved and the patient was discharged. After two months she came back to our department due to the same disease on her left leg that we treated with the therapy previously used. We highlight the long time, 7 years, elapsed between liquid silicone injection and onset of cutaneous symptoms.


Asunto(s)
Absceso/etiología , Técnicas Cosméticas/efectos adversos , Fístula Cutánea/etiología , Traumatismos de la Pierna/etiología , Siliconas/efectos adversos , Infecciones Estreptocócicas/etiología , Streptococcus agalactiae/aislamiento & purificación , Infección de Heridas/complicaciones , Absceso/tratamiento farmacológico , Absceso/microbiología , Absceso/cirugía , Corticoesteroides/uso terapéutico , Adulto , Antibacterianos/uso terapéutico , Ceftriaxona/uso terapéutico , Fístula Cutánea/cirugía , Drenaje , Quimioterapia Combinada , Edema/etiología , Eritema/etiología , Femenino , Humanos , Inyecciones Subcutáneas/efectos adversos , Traumatismos de la Pierna/microbiología , Rifamicinas/uso terapéutico , Siliconas/administración & dosificación , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/cirugía , Factores de Tiempo
5.
Langmuir ; 20(13): 5241-6, 2004 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-15986658

RESUMEN

Biocompatible systems formulated for use in the food, cosmetic, and pharmaceutical fields are characterized. Ternary phase diagrams of mixtures of natural lipids (glycerol trioleate, glycerol monooleate, diglycerol monooleate, and lecithin) and water were investigated by means of optical microscopy in polarized light and by multinuclear NMR spectroscopy. All systems showed a microemulsion region at high oil content and a large area of coexistence of two liquid crystalline (hexagonal and lamellar) phases. 1H and 13C NMR self-diffusion measurements were used to characterize microstructural features of the microemulsions. On water dilution, the two-phase liquid crystalline region transforms into a creamy emulsion area where the droplets of water are stabilized by both the lamellar and the hexagonal phases, as indicated by 2H NMR measurements. Due to the very effective dispersing action of the two liquid crystalline phases, these emulsions show a high stability toward phase separation.


Asunto(s)
Materiales Biocompatibles/química , Lípidos/química , Transición de Fase , Difusión , Emulsiones/química , Espectroscopía de Resonancia Magnética
6.
Clin Ter ; 153(2): 85-91, 2002.
Artículo en Italiano | MEDLINE | ID: mdl-12078345

RESUMEN

A survey of 5 year period activity (1995-99) of a university consultation-liaison service is reported, concerning 1556 psychiatric consultations. The majority of referrals (68%) came from internal medicine units; the reason of referral was prevalently due (approx. 50%) to the presence of psychiatric symptoms; moreover, the majority of patients (approx. 51%) for which the consultation has been requested were already under psychiatric treatment and 32% of them took psychoactive drugs. In 75% of cases a psychiatric diagnosis according to ICD-10 was formulated after consultation: "Affective syndromes" were diagnosed in 25% of cases and "Neurotic, somatoformand stress-related syndromes" in 36.6% of cases. Approx. 60% of patients were prescribed psychoactive drugs; 50% received psychological support.


Asunto(s)
Trastornos Mentales/diagnóstico , Trastornos Mentales/tratamiento farmacológico , Servicio de Psiquiatría en Hospital/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fármacos del Sistema Nervioso Central/uso terapéutico , Femenino , Hospitales Generales , Hospitales Universitarios , Humanos , Italia , Masculino , Persona de Mediana Edad
7.
Soc Psychiatry Psychiatr Epidemiol ; 37(3): 112-7, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11990007

RESUMEN

BACKGROUND: The aim of the present study was to compare the prevalence of ICD-10 psychiatric disorders in a community sample of subjects of Sardinian origin resident in Paris (here "immigrants"), of the general Parisian population ("Parisians") and of Sardinians resident in Sardinia ("Sardinians"). METHODS: The sample of immigrants was obtained by contacting a fifth of all households with a Sardinian surname in Paris telephone directories. The other samples have already been partially described in previous studies. All subjects were interviewed using the CIDIS, a shortened version of the structured WHO interview CIDI. RESULTS: High or very high response rates were achieved in all studies. The final sample sizes were: 153 immigrants, 2,260 Parisians and 1,040 Sardinians. Immigrants showed high rates of depressive disorders, as did Parisians, and high rates of anxiety disorders, as did Sardinians. The immigrants' offspring (second-generation immigrants) seemed to be particularly at risk for depression, drug-abuse and bulimia. Elderly Sardinians who had returned to Sardinia after a long period of emigration showed an increased risk of dysthymia. The presence of a confidential relationship had a protective effect. CONCLUSIONS: The results are consistent with previous findings which suggest a greater risk of anxiety disorders in Southern Europe and of depression in Northern European countries. Immigrants in this study seem to present a particularly unfavourable pattern of mental disorders compared to both origin and host populations. The role of social support, use of mental health services and social conditions of second-generation immigrants should be analysed in greater depth.


Asunto(s)
Trastornos Mentales/etnología , Adulto , Distribución por Edad , Anciano , Trastorno Depresivo/etnología , Femenino , Humanos , Italia/etnología , Masculino , Estado Civil , Persona de Mediana Edad , Paris/epidemiología , Prevalencia , Distribución por Sexo
8.
J Invest Dermatol ; 116(5): 728-30, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11348461

RESUMEN

Psoriasis is a chronic skin disorder affecting approximately 2% of the Caucasian population. Family clustering of the disease is well established and nonparametric linkage analyzes have mapped disease susceptibility loci on chromosomes 6p (PSORS1) and 17q (PSORS2). Nonconfirmed evidence for linkage is also available for chromosomes 2q 3q, 4q (PSORS3), 8q, 16q, and 20p. We mapped an additional susceptibility locus on chromosome 1q21 (PSORS4). In this study, we have carried out a linkage disequilibrium analysis, in order to achieve a finer localization. We recruited 79 triads from continental Italy and typed them at five loci spanning the 1.6 Mb region generating the highest multipoint LOD scores in our previous linkage study. We observed significant evidence for association with D1S2346 marker (p = 0.004). Results consistent with this data were obtained by typing an independent sample that included 28 patients and 56 controls, originating from Sardinia. In fact, p values of 0.02 were observed with both D1S2346 and D1S2715 markers. We sought further confirmation of our results by typing both samples with two novel markers (140J1C and 140J1D) flanking D1S2346. Marker 140J1D generated a p value of 0.003 in the continental Italy sample where a D1S2346/140J1D haplotype was found with a higher frequency among patients' chromosomes. Altogether our data indicate that the 1q21 susceptibility gene may be localized in the genomic interval spanned by D1S2346 and 140J1D. This report provides evidence supporting the refinement of a non-HLA psoriasis susceptibility locus.


Asunto(s)
Mapeo Cromosómico , Cromosomas Humanos Par 1/genética , Predisposición Genética a la Enfermedad/genética , Psoriasis/genética , Frecuencia de los Genes , Ligamiento Genético , Marcadores Genéticos , Haplotipos , Humanos , Italia , Escala de Lod , Repeticiones de Microsatélite , Valores de Referencia
9.
Chem Phys Lipids ; 110(1): 11-7, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11245830

RESUMEN

The addition of hydrophilic and hydrophobic molecules to the 1-monooleoyl glycerol (MO)/water (W) system has been investigated at a molecular level by 13C nuclear magnetic resonance (NMR) relaxation. Depending on the nature of the additive, the liquid crystalline phases of the MO/W binary system are modified. The 13C NMR spin lattice relaxation rates of the various MO carbons were determined in the presence of the additives for different types of L(2) and liquid crystalline phases. Data revealed that local dynamics are independent of type and amount of additive (within 5 wt.%), and also of the type of the structural arrangement. The curvature of the interface does not affect the local mobility of MO carbons, with the exception of the glycerol G3 and the carboxylic C1 carbons. Moreover, the presence of the double bond in the mid part of the hydrocarbon chain induces a levelling in the relaxation rates on the neighboring carbons. The 13C NMR spin lattice relaxation rates at two magnetic field strengths and the Overhauser enhancement were measured in the L(2) phase of the MO/W/sodium decanoate system. The use of a two-step model of relaxation allowed to estimate order parameters, and slow and fast motions of MO in the structured aggregate.


Asunto(s)
Glicéridos/química , Espectroscopía de Resonancia Magnética , Agua/química , Geles/química , Modelos Moleculares
10.
Neurol Sci ; 22(4): 321-4, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11808856

RESUMEN

Epilepsy is the main clinical manifestation of neurocysticercosis (NC). We studied an adult subject who presented a seizure disorder mimicking an acute confusional state as clinical expression of NC. Diagnosis was made with neuroimaging and western blot determination of specific antibodies on serum. Computed tomography and magnetic resonance imaging displayed multiple calcifications and a few transitional cysts in the cerebral parenchyma. Electroencephalography showed a pattern of periodic lateralized epileptiform discharges (PLEDs) which could be related topographically to a cystic lesion located in the left parietal lobe. In our view there was a clear pathogenic correlation between the seizure disorder and the parasitic cyst located in the left parietal lobe. Neither antiepileptic drugs nor steroids were prescribed. Follow-up to one year ruled out other clinical manifestations of the disease. This case is an example of acute symptomatic seizure related to a transitional cystic lesion of NC.


Asunto(s)
Epilepsia/diagnóstico , Epilepsia/parasitología , Neurocisticercosis/complicaciones , Neurocisticercosis/diagnóstico , Enfermedad Aguda , Confusión/diagnóstico , Confusión/parasitología , Diagnóstico Diferencial , Electroencefalografía , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad
11.
Neurology ; 55(6): 842-8, 2000 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-10994006

RESUMEN

OBJECTIVE: To verify incidence rates and their temporal trend in a homogeneous, ethnically, and genetically distinct population of central Sardinia (the Nuoro province). BACKGROUND: Intensive epidemiologic studies carried out in Sardinia since the 1970s have suggested that the prevalence and incidence of MS are much higher in this Mediterranean island compared with those found on mainland Italy. METHODS: The study area had a population of approximately 274, 000 people in the 1991 census. The authors adopted a complete enumerative approach by reviewing all possible sources of case collection available in the investigative area. RESULTS: Based on 469 MS patients, the mean annual incidence for 1955 to 1995 was 4.18 per 100,000 (or 4.3 per 100,000 if age- and sex-adjusted to the European population). The incidence, averaging 1.95 per 100,000 during 1955 to 1959, rose progressively over time, reaching rates of 6.6 in the quinquiennium 1985 to 1989 and 6.4 per 100,000 in 1990 to 1995. On December 31, 1994, the crude prevalence, based on 415 MS patients alive in the study area, was 151.9 per 100,000 (156.6 if adjusted to the European population). CONCLUSION: These incidence and prevalence rates are the highest to date that have been estimated for a large community in southern Europe, and they constitute some of the highest rates in the world. Based on other surveys, these results reinforce the position of Sardinia as a higher and rising prevalence area for MS compared with other Mediterranean populations. Genetic and social-historic data strengthen the hypothesis of the environmental role and genetic factors among Sardinians in determining the notable difference in MS frequency between Sardinians and other Mediterraneans.


Asunto(s)
Distrofias Musculares/epidemiología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia
12.
Brain Res Bull ; 51(5): 425-31, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10715564

RESUMEN

The effect of adrenocorticotropin (ACTH)(1-24) and alpha-melanocyte stimulating hormone (alpha-MSH) on grooming, stretching, yawning and penile erection was studied after injection into different brain areas. Both peptides induce the above responses when injected into the hypothalamic periventricular region of the third ventricle. This region includes the paraventricular nucleus, the dorsomedial nucleus, the ventromedial nucleus and the anterior hypothalamic area. The minimal effective dose of both peptides was 0.5 microg and the maximal effect was seen with 2 microg, the highest dose tested. Irrespective of the injection site, grooming started 5-7 min after injection of either peptide, while stretching, yawning and penile erection started only after 15-35 min and lasted for 90-120 min. In contrast both peptides were ineffective when injected into the preoptic area, the caudate nucleus or the CA1 field of the hippocampus. Grooming, stretching and yawning, but not penile erection, were prevented by cyclic[AcCys(11), D-Nal(14), Cys(18), AspNH(2)(22)]-beta-MSH (11-22) (HS014), a selective melanocortin 4 receptor antagonist, injected into the same periventricular area 10 min before of ACTH(1-24) or alpha-MSH. The results show that ACTH(1-24) and alpha-MSH act in the hypothalamic periventricular region to induce the above responses and that grooming, stretching and yawning, but not penile erection, are mediated by melanocortin 4 receptors.


Asunto(s)
Mapeo Encefálico , Cosintropina/farmacología , Aseo Animal/fisiología , Erección Peniana/fisiología , Receptores de Corticotropina/fisiología , Bostezo/fisiología , alfa-MSH/farmacología , Animales , Masculino , Microinyecciones , Péptidos Cíclicos/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Melanocortina
13.
Acta Neurol Scand ; 98(6): 391-4, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9875616

RESUMEN

OBJECTIVES: To verify morbidity estimates in central Sardinia, Italy. METHODS: A prevalence study was performed in the province of Nuoro, Central Sardinia, which has a population of 273,768 inhabitants (135,383 men and 138,385 women). A complete enumeration approach was adopted by using all possible case-collection sources. RESULTS: On prevalence day, December 31, 1993, 394 subjects (124 men and 270 women) living in the study area were known to suffer from definite and probable MS, giving a crude prevalence rate of 143.9 cases per 100,000 people, 91.6 for males and 195.11 for females. The crude prevalence estimated on December 31, 1985, based on 282 MS cases alive in the study area, was 102.94 per 100,000. CONCLUSION: This study reinforced central Sardinia's position as a high and rising prevalence area for MS.


Asunto(s)
Esclerosis Múltiple/epidemiología , Adolescente , Adulto , Factores de Edad , Edad de Inicio , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Italia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores Sexuales
14.
Minerva Pediatr ; 44(12): 593-4, 1992 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-1301483

RESUMEN

The paper reports the case of a neonate suffering from autoimmune neonatal thrombocytopenia whose mother had suffered from previous idiopathic thrombocytopenia purpura. Although asymptomatic, the baby received early treatment with high doses of immunoglobulin G (1 g/kg) in a single dose. Treatment was repeated on day 12 using the same method. No other treatment was associated with IgG. The Authors confirm the good level of tolerability and efficacy of IgG in the treatment of autoimmune neonatal thrombocytopenia without complications.


Asunto(s)
Inmunoglobulina G/uso terapéutico , Trombocitopenia/tratamiento farmacológico , Autoinmunidad , Desarrollo Embrionario y Fetal , Femenino , Humanos , Inmunoglobulina G/administración & dosificación , Recién Nacido , Inyecciones Intravenosas , Masculino , Intercambio Materno-Fetal , Embarazo , Trombocitopenia/inmunología
15.
Pediatr Med Chir ; 11(5): 541-2, 1989.
Artículo en Italiano | MEDLINE | ID: mdl-2631062

RESUMEN

Case report of a iatrogenic benign intracranial hypertension in a 7 months old infant. Unlike in the child and the adult, this syndrome has a peculiar non specific clinical pattern in the infant. Having ruled out other specific acute diseases of the central nervous system, it seems reasonable not to start any treatment since the outcome of this condition is always benign.


Asunto(s)
Analgésicos/efectos adversos , Antipirina/análogos & derivados , Seudotumor Cerebral/inducido químicamente , Sulfametoxipiridazina/análogos & derivados , Antipirina/efectos adversos , Humanos , Lactante , Masculino , Sulfametoxipiridazina/efectos adversos
18.
Pediatr Med Chir ; 9(4): 487-8, 1987.
Artículo en Italiano | MEDLINE | ID: mdl-3697329

RESUMEN

One case of a 13-months-old-female infant with transient idiopathic hyperphosphatasemia is described. This syndrome is characterized by: 1) increased serum alkaline phosphatase activity not associate with an organic disease; 2) normalization of the enzyme activity within 12 weeks. Familial hyperphosphatasemia, a permanens disease, is also excluded because of ALP normal values in both parents. Rickets, hepatic and biliary diseases are excluded by clinical, radiologic and laboratory data.


Asunto(s)
Fosfatasa Alcalina/sangre , Desarrollo Infantil/fisiología , Humanos , Lactante , Masculino
19.
Pediatr Med Chir ; 8(3): 417-8, 1986.
Artículo en Italiano | MEDLINE | ID: mdl-3786206

RESUMEN

Kawasaky's disease is a multisystem widespread vasculitis. Besides the mucocutaneous patterns, symptoms related to various organs have been observed in the medical literature. Lethargy, irritability, meningism and cranial nerves paralysis occur in the acute phase of central nervous system involvement. The A.A. report a rare cerebellar syndrome caused by vasculitis in a seven years old girl's cerebellum. Surveillance of tardive complications must be undertaken in patients affected by Kawasaky's disease.


Asunto(s)
Enfermedades Cerebelosas/etiología , Síndrome Mucocutáneo Linfonodular/complicaciones , Enfermedades Cerebelosas/psicología , Circulación Cerebrovascular , Niño , Femenino , Humanos , Trastornos del Humor/etiología , Trastornos del Movimiento/etiología
20.
Biochem Int ; 9(4): 437-46, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6517952

RESUMEN

The effects of irradiation of pig kidney Dopa decarboxylase by visible light absorbed by the intrinsic chromophore, pyridoxal-P, and by the externally added dyes, pyridoxal-P or proflavin, have been studied. In all cases inactivation was observed, even though to different extens, which seemed to be essentially correlated to tryptophanyl residues photodestruction. Kinetics of inactivation and oxidation of these amino acid residues revealed the presence of two distinct groups of tryptophan residues with different photooxidation rate constants. A different role for these classes of residues in the structure and function of Dopa decarboxylase has been suggested.


Asunto(s)
Descarboxilasas de Aminoácido-L-Aromático/efectos de la radiación , Dopa-Decarboxilasa/efectos de la radiación , Riñón/enzimología , Luz , Aminoácidos/análisis , Animales , Colorantes , Dopa-Decarboxilasa/metabolismo , Oxidación-Reducción , Fotoquímica , Proflavina/farmacología , Fosfato de Piridoxal/farmacología , Porcinos , Triptófano/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA