SummaryBackground Pituitary adenomas (PAs) are associated with increased morbidity and mortality. The optimal delivery of services and the provision of care for patients with PAs require distribution of the resources proportionate to the impact of these conditions on the community. Currently, the resource allocation for PAs in the health care system is lacking a reliable and an up-to-date epidemiological background that would reflect the recent advances in the diagnostic technologies, leading to the earlier recognition of these tumours. Objectives To determine the prevalence, the diagnostic delay and the characteristics of patients with PA in a well-defined geographical area of the UK (Banbury, Oxfordshire). Patients and methods Sixteen general practitioner (GP) surgeries covering the area of Banbury and a total population of 89 334 inhabitants were asked to participate in the study (data confirmed on 31 July 2006). Fourteen surgeries with a total of 81,449 inhabitants (91% of the study population) agreed to take part. All cases of PAs were found following an exhaustive computer database search of agreed terms by the staff of each Practice and data on age, gender, presenting manifestations and their duration, imaging features at diagnosis, history of multiple endocrine neoplasia type 1 and family history of PA were collected. Results A total of 63 patients with PA were identified amongst the study population of 81,149, with a prevalence of 77AE6 PA cases/ 100,000 inhabitants (prolactinomas; PRLoma: 44AE4, nonfunctioning PAs: 22AE2, acromegaly; ACRO: 8AE6, corticotroph adenoma: 1AE2 and unknown functional status; UFS: 1AE2/100,000 inhabitants). The distribution of each PA subtype was for PRLoma 57%, nonfunctioning PAs 28%, ACRO 11%, corticotroph adenoma 2% and UFS 2%. The median age at diagnosis and the duration of symptoms until diagnosis (in years) were for PRLoma 32AE0 and 1AE5, nonfunctioning PAs 51AE5 and 0AE8, ACRO 47 and 4AE5 and corticotroph adenoma 57 and 7, respectively. PRLoma was the most frequent PA diagnosed up to the age of 60 years (0-20 years: 75% and 20-60 years: 61% of PAs) and nonfunctioning PA after the age of 60 years (60% of PAs). Nonfunctioning PAs dominated in men (57% of all men with PA) and PRLoma in women (76% of all women with PA). Five patients (7AE9%) presented with classical pituitary apoplexy, with a prevalence of 6AE2 cases/100,000 inhabitants. Conclusions Based on a well-defined population in Banbury (Oxfordshire, UK), we have shown that PAs have a fourfold increased prevalence than previously thought; our data confirm that PAs have a higher burden on the Health Care System and optimal resource distribution for both clinical care and research activities aiming to improve the outcome of these patients are needed.

Despite patients being treated early and frequently with immunomodulators and biological therapy in Western Europe, 5-year outcomes including surgery and phenotype progression in this cohort were comparable across Western and Eastern Europe. Differences in treatment strategies between Western and Eastern European centres did not affect the disease course. Treatment with immunomodulators reduced the risk of surgery and hospitalisation.

This article explores the use of principal component analysis (PCA) and T2 and Q-statistic measures to detect and distinguish damages in structures. For this study, two structures are used for experimental assessment: a steel sheet and a turbine blade of an aircraft. The analysis has been performed in two ways: (i) by exciting the structure with low-frequency vibrations using a shaker and using several piezoelectric (PZT) sensors attached on the surface, and (ii) by exciting at high-frequency vibrations using a single PZT as actuator and several PZTs as sensors. A known vibration signal is applied and the dynamical responses are analyzed. A PCA model is built using data from the undamaged structure as a reference base line. The defects in the turbine blade are simulated by attaching a mass on the surface at different positions. Instead, a progressive crack is produced to the steel sheet. Data from sets of experiments for undamaged and damaged scenarios are projected into the PCA model. The first two projections, and the Q-statistic and T2-statistic indices are analyzed. Q-statistic indicates how well each sample conforms to the PCA model. It is a measure of the difference or residual between a sample and its projection into the principal components retained in the model. T2-statistic index is a measure of the variation of each sample within the PCA model. Results of each scenario are presented and discussed demonstrating the feasibility and potential of using this formulation in structural health monitoring.

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The proposition of the hypothesis-relating structure with properties of asphaltenes is a very important endeavor. In view of their complexity, being an intricate mixture of high-molecular-mass compounds, experimental and theoretical procedures must be designed to check whether the structures proposed are consistent with expected and found behavior. During recent years, a structural characteristic of asphaltene, whereby the several polycyclic systems present in them are joined by flexible aliphatic chains, has been proposed by several authors. For simplicity, we will refer to this as the rosary-type structure. In this paper, using both reported as well as new experimental and theoretical results, an attempt is made to show how asphaltene properties, such as molecular-mass distribution, molecular fragmentation, solubility, adsorption, trapping of molecules, solvent swelling, and aging, could be accounted for in terms of the above rosary-type structures.

There are unresolved issues regarding sustained virological response (SVR), tolerance and risk of rejection following antiviral therapy in liver transplantation (LT). The aim of our study was to determine efficacy, rejection risk and factors associated with SVR. HCV-infected LT patients with at least 6 months of follow-up following end-of-therapy (EOT) received combination therapy of ribavirin (Rbvr) ϩ standard (nϭ31)/pegIFN (nϭ36) between 1999 and 2004 (95% genotype 1). An EOT and SVR was obtained in 46% and 33%, respectively. Type of antiviral therapy, use of erythropoietin, compliance, and early virologic response (EVR) were predictive of SVR, but only the latter remained in the multivariate analysis. Premature discontinuation, not impacted by the use of erythropoietin or GCSF, occurred in 40% patients. None of the variables predicted rejection (acute nϭ2, chronic nϭ4). A SVR occurred in 3/4 patients with chronic rejection. In conclusion, the efficacy of pegIFN-Rbvr is similar to the non-transplant population. An EVR at 3 months is useful to predict lack of response. The type of calcineurin inhibitor and history of prior non-response to IFN before LT do not influence the outcome of therapy. Severe rejection may lead to graft loss, a complication difficult to predict.

Adsorption of asphaltenes on glass surface has been studied by using photothermal surface deformation spectroscopy. This technique was adapted for direct measurement of the amount of asphaltene adsorbed on glass plate surfaces. Solid-solution adsorption isotherms for asphaltenes were obtained at room temperature in toluene. Stepwise or multilayer adsorption was detected in the three cases examined (Furrial, Jobo, and Hamaca) after long contact periods. After the first layer due to glass surface saturation one (Jobo and Hamaca) or two (Furrial) further layers were measured. Analysis of results suggests that this adsorption behavior could be related to the sudden increase of aggregate concentration typical of micelle formation. For instance, below 4000 mg/L Furrial asphaltenes behave like a mixture containing two surfactants with cmc of 1500 and 3000 mg/L, respectively. A slow increase in molecular weight when measured in toluene was observed for Hamaca (from 4230 to 17420) and Cerro Negro (from 5350 to 15170) over a 3 day period, suggesting a slow formation of aggregates. Accordingly, the above stepwise adsorption takes a long time to appear (more than 3 days). Isotherms measured at shorter times only showed a continuous but not stepwise increase in adsorption with concentration.