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Los adenomas hipofisarios representan un 15% de los tumores intracraneales benignos. Presentamos los resultados quirúrgicos obtenidos desde la introducción en nuestro centro del abordaje endoscópico endonasal transesfenoidal (EET) en 2005.

Presentamos nuestra experiencia en el cierre de fístulas de líquido cefalorraquídeo según su tamaño y localización.

Positron emission tomography (PET) and network analysis have been used to identify a reproducible pattern of regional metabolic covariation that is associated with idiopathic Parkinson's disease (PD). The activity of this PD‐related pattern can be quantified in individual subjects and used to discriminate PD patients from atypical parkinsonians. Because PET is not commonly available, we sought to determine whether similar discrimination could be achieved using more routine single photon emission computed tomography (SPECT) perfusion methods. Twenty‐three subjects with PD (age, 63 ± 9 years), 22 subjects with multiple system atrophy (MSA; age, 64 ± 7 years), and 20 age‐matched healthy controls (age, 62 ± 13 years) underwent SPECT imaging of regional cerebral perfusion with Tc‐99m ethylene cysteinate dimer (ECD). Using network analysis, we determined whether a PD‐related pattern existed in the SPECT data, and whether its expression discriminated PD from MSA patients. Additionally, we compared the accuracy of group discrimination achieved by this pattern with that of the PET‐derived PD‐related pattern applied to the SPECT data. Network analysis of the SPECT data identified a significant pattern characterized by relative increases in cerebellar, lentiform, and thalamic perfusion covarying with decrements in the frontal operculum and in the medial temporal cortex. Subject scores for this pattern discriminated PD patients from controls (P< 0.01) and from MSA patients (P< 0.03). Subject scores for the PET‐derived PD‐related pattern computed in the individual SPECT scans more accurately distinguished PD patients from controls (P< 0.005) and from MSA patients (P= 0.0002). A significant PD‐related covariance pattern can be identified in SPECT perfusion data. Moreover, the disease related pattern identified previously with PET can be applied to individual SPECT perfusion scans to provide group discrimination between PD patients, healthy controls, and individuals with MSA. Because of significant individual subject overlap between groups, however, the clinical utility of this method in the differential diagnosis of Parkinsonism remains uncertain. © 2002 Movement Disorder Society

An investigation of the nutrient intake of a large-scale sample (n= 35 072), drawn from the Italian school-age population (7 – 10 years) was carried out in a nationwide survey of nutritional patterns. Friuli, the Piedmont, Latium and Sicily regions were selected as representative of the nation's north-south and east-west socio-economic divisions. A food frequency questionnaire was used to assess nutritional intake. Traditional methods of 24-h dietary recall and a weighted food diary were used in sub-samples to assess the’ validity of the food frequency questionnaire. Our data suggest that the average diet of Italian schoolchildren is rich in protein (especially animal proteins) and lipids (prevalently saturated fatty acids), but that carbohydrate and fibre intakes remain generally low. The relatively low calcium intake among girls and a widespread, more than adequate iron intake are also noteworthy. The food and nutrient intakes assessed suggest a dietary pattern with several positive points, but also reveal potential hazards for a wider population spectrum. The type of large-scale nutritional monitoring with a multimethod approach can be used in Italy and elsewhere to describe the dietary trends of a school-age population.

The calcium intakes of 35 072 Italian schoolchildren aged 7 – 10 years were investigated as part of a nation-wide survey of nutritional patterns. The Friuli, Piedmont, Latium and Sicily regions of Italy were selected as representative of the nation's north–south and east–west socio-economic divisions. A food-frequency questionnaire was used to assess the nutritional intakes of the whole sample. The validity of the food-frequency questionnaire method was assessed in a sub-sample of children by traditional methods: 24-h dietary recall and a weighted food diary. The data indicate that the mean calcium intakes of girls were below the recommended daily intake of 800 mg in all of the regions except Sicily, and that the calcium intakes of boys were above the recommended daily intake in all of the regions except Friuli. These results suggest that there may be deficiencies in the calcium intakes of this age-group in the wider population, particularly in girls. Food-frequency questionnaires are potentially valuable as part of a multi-method approach in large-scale nutritional monitoring.

We study the Kronrod extensions of Gaussian quadrature rules whose weight functions on [−1, 1] consist of any one of the four Chebyshev weights divided by an arbitrary quadratic polynomial that remains positive on [−1, 1]. We show that in almost all cases these extended “Gauss–Kronrod” quadrature rules have all the desirable properties: Kronrod nodes interlacing with Gauss nodes, all nodes contained in [−1, 1], and all weights positive and representable by semiexplicit formulas. Exceptions to these properties occur only for small values of n(the number of Gauss nodes), namely n⩽ 3, and are carefully identified. The precise degree of exactness of each of these Gauss–Kronrod formulae is determined and shown to grow like 4n, rather than 3n, as is normally the case. Our findings are the result of a detailed analysis of the underlying orthogonal polynomials and “Stieltjes polynomials”. The paper concludes with a study of the limit case of a linear divisor polynomial in the weight function.

We prove that there is no positive measure $ d\sigma $ $ d\sigma (t) = \omega (t)dt$ $ \omega (t)$, and the Gauss-Kronrod formula is required to have equal weights only for n even. We also show that the only positive and even measure $ d\sigma (t) = d\sigma ( - t)$ for which the Gauss-Kronrod formula has all weights equal if $ n = 1$ $ \smallint _{ - 1}^1f(t)d\sigma (t) = w\Sigma _{\nu = 1}^nf({\tau _\nu }) + {w_1}f(1) + w\Sigma _{\mu = 2}^nf(\tau _\mu ^\ast) + {w_1}f( - 1) + R_n^K(f)$, is the Chebyshev measure of the first kind .

We study Gauss-Kronrod quadrature formulae for the Jacobi weight function $ {w^{(\alpha ,\beta )}}(t) = {(1 - t)^\alpha }{(1 + t)^\beta }$ $ \alpha = \beta = \lambda - \frac{1}{2}$ $ (\alpha ,\beta )$, for which the quadrature rule has (a) the interlacing property, i.e., the Gauss nodes and the Kronrod nodes interlace; (b) all nodes contained in $ ( - 1,1)$ $ n = 1(1)20(4)40$ $ n = 1(1)10$n is the number of Gauss nodes. Algebraic criteria, in particular the vanishing of appropriate resultants and discriminants, are used to determine the boundaries of the regions identifying properties (a) and (d). The regions for properties (b) and (c) are found more directly. A number of conjectures are suggested by the numerical results. Finally, the Gauss-Kronrod formula for the weight $ {w^{(\alpha ,1/2)}}$ $ {w^{(\alpha ,\alpha )}}$ $ w(t) = \vert t{\vert^\gamma }{(1 - {t^2})^\alpha }$ .

•Subarachnoid hemorrhage (SAH), developed after burr-hole evacuation of CSDH is an extremely rare finding.•A 64 year’s old man developed a bilateral temporo-parietal SAH the day after evacuation of a bilateral CSDH.•We suppose the rapid brain shift during surgery was the main cause of SAH development.