Validation of a method for measuring (226)Ra in drinking waters by LSC

A simple method for measuring (226)Ra in drinking waters has been validated and validation parameters are provided. It is based on the measurement by LSC of (222)Rn, at equilibrium with (226)Ra, which is absorbed into a water immiscible scintillation cocktail (Ultima Gold F) inside the counting vial. The validated application field ranges between the detection limit (2·10(-3) Bq/kg) to 150 Bq/kg. The method has proven to be reliable, effective and suitable for wide-range measuring campaigns. A summary of results obtained in recent years is also given.

Non-invasive measurement of choroidal volume change and ocular rigidity through automated segmentation of high-speed OCT imaging

We have developed a novel optical approach to determine pulsatile ocular volume changes using automated segmentation of the choroid, which, together with Dynamic Contour Tonometry (DCT) measurements of intraocular pressure (IOP), allows estimation of the ocular rigidity (OR) coefficient. Spectral Domain Optical Coherence Tomography (OCT) videos were acquired with Enhanced Depth Imaging (EDI) at 7Hz during ~50 seconds at the fundus. A novel segmentation algorithm based on graph search with an edge-probability weighting scheme was developed to measure choroidal thickness (CT) at each frame. Global ocular volume fluctuations were derived from frame-to-frame CT variations using an approximate eye model. Immediately after imaging, IOP and ocular pulse amplitude (OPA) were measured using DCT. OR was calculated from these peak pressure and volume changes. Our automated segmentation algorithm provides the first non-invasive method for determining ocular volume change due to pulsatile choroidal filling, and the estimation of the OR constant. Future applications of this method offer an important avenue to understanding the biomechanical basis of ocular pathophysiology.

Guidelines and management of hospitalized patients with community-acquired pneumonia: the Italian experience of the FASTCAP study

BACKGROUND Nowadays few data are available addressing the validation of guidelines concerning diagnosis and treatment of Community-Acquired Pneumonia (CAP) in clinical practice. AIM OF THE STUDY To evaluate the impact of compliance to the recommendations issued by the Italian Federation of Internal Medicine (FADOI) in 2002 on the management of hospitalised CAP. METHODS National, multicentre, interventional, “before-after” survey, performed in 31 hospitals in Italy. All patients with CAP of Fine class IV or V (excluding those who were directly admitted to intensive care units) were included. The study was composed of three consecutive periods: 1) a retrospective phase (RP); 2) guideline implementation; 3) a prospective phase (PP). Results were expressed as Odds Ratios (OR) with 95% confidence intervals (95% CI) adjusted for risk factors and corrected for multiple comparisons in subgroups. RESULTS A significant increase in use of combinations was observed in the PP (p = 0.006). Moreover, a shift of prescription from β-lactams to fluoroquinolones as initial monotherapy was recorded. Therapies adherent to FADOI recommendations increased by 10.9% in the PP (p < 0.001). Therapeutic success improved after implementation of recommendations (73.9 vs 71.5%; OR = 0.83; 95% CI = 0.69-1.00; p = 0.049). The difference was particularly evident in Fine class V (58.0 vs 52.5%; OR = 0.71; 95% CI = 0.51-0.98; p = 0.036), where a trend towards a lower mortality occurred (23.1 vs 26.3%; OR = 0.71; 95% CI = 0.48-1.05; p = 0.090). Therapies compliant with FADOI recommendations showed a higher success rate in both study phases (76.6% vs 70.3%; OR = 0.74; 95% CI = 0.60-0.90; p = 0.004). Levofloxacin was the most clinically effective first-cycle therapy with 79.1% of success, the least effective being an antipneumococcal cephalosporin alone with 68.6% (OR = 0.72; 95% CI = 0.51-1.01; p = 0.053). Etiologic diagnosis was obtained in less than 12% of patients in both study phases. Mean lengths of hospital stay were 12.2 and 11.9 days in the RP and PP, respectively. CONCLUSIONS Implementation of FADOI therapeutic recommendations led to a significantly better outcome in terms of clinical success, especially in more severe cases of CAP. Possibly, more “aggressive” approaches towards implementation may result in further improvement in the overall management of CAP.

Automatic 3D reconstruction of quasi-planar stereo Scanning Electron Microscopy (SEM) images

Scanning Electron Microscopy (SEM) is widely used in science to characterize the surface roughness of materials. Three-dimensional information can be obtained with SEM based on stereovision techniques. A stereo pair is typically obtained by tilting the sample by a few degrees. In this paper we present a fully automated method for 3D reconstruction from a SEM stereo pair without any particular constraint. Results are presented for corneal stromal surfaces.

Analyzing speckle contrast for HiLo microscopy optimization

HiLo microscopy is a recently developed technique that provides both optical sectioning and fast imaging with a simple implementation and at a very low cost. The methodology combines widefield and speckled illumination images to obtain one optically sectioned image. Hence, the characteristics of such speckle illumination ultimately determine the quality of HiLo images and the overall performance of the method. In this work, we study how speckle contrast influence local variations of fluorescence intensity and brightness profiles of thick samples. We present this article as a guide to adjust the parameters of the system for optimizing the capabilities of this novel technology.

Spectral-domain phase microscopy with improved sensitivity using two-dimensional detector arrays

In this work we demonstrate the use of two-dimensional detectors to improve the signal-to-noise ratio (SNR) and sensitivity in spectral-domain phase microscopy for subnanometer accuracy measurements. We show that an increase in SNR can be obtained, from 82 dB to 105 dB, using 150 pixel lines of a low-cost CCD camera as compared to a single line, to compute an averaged axial scan. In optimal mechanical conditions, phase stability as small as 92 μrad, corresponding to 6 pm displacement accuracy, could be obtained. We also experimentally demonstrate the benefit of spatial-averaging in terms of the reduction of signal fading due to an axially moving sample. The applications of the improved system are illustrated by imaging live cells in culture.

Patient and operator exposure during percutaneous vertebroplasty

PURPOSE

The purpose of this study was to compare exposure of patient and operator to ionising radiation during percutaneous vertebroplasty performed under combined computed tomography (CT) and fluoroscopic guidance or fluoroscopic guidance alone.

MATERIALS AND METHODS

With the collaboration of our physics department, we measured exposure on ten patients undergoing vertebroplasty with combined CT and fluoroscopic guidance and on ten undergoing vertebroplasty with fluoroscopic guidance alone.

RESULTS

Mean operator dose was approximately 0.8 microSv during vertebroplasty done with combined CT and fluoroscopic guidance and 5.8 microSv in procedures with fluoroscopic guidance alone. Mean patient dose was approximately 6 mSv for combined guidance and 8 mSv for fluoroscopic guidance, a difference that was not found to be statistically significant.

CONCLUSIONS

Although combined CT and fluoroscopic guidance is normally preferred for difficult areas such as the cervical and upper thoracic vertebrae, to ensure operator radiation protection, the technique should also be considered for areas normally treated under fluoroscopic guidance alone. However, a larger patient series is needed to correctly evaluate the real contribution of low-dose CT to patient exposure.

[A rare case of esophageal atresia type I]

An extremely rare case of type A esophageal atresia is reported. The baby girl patient born spontaneously after a 38-week pregnancy, was diagnosed prenatally with suspected type A esophageal atresia. Diagnosis was confirmed at birth by chest and abdominal X-ray. As per protocol, a naso-esophageal tube was positioned in aspiration and a Stamm gastrostomy made for nutritional purposes. Evaluation of the distance between blind pouches at one month of life showed they were overlapping. At intervention the pouches were found to be united by a fibrous bridge about 1.5 cm long. Anastomosis was carried out with ease. The postoperative course was trouble-free. On the X day the baby girl was being fed completely per os. Histolo-gical examination of the fibrous residue excluded the presence of a mucosa-lined lumen. X-ray examination of the esophageal-gastric passage, one month after the operation, showed the smooth transit of the contrast medium and an adequate anastomotic lumen. At follow-up, at the age of 9 months, the baby was growing normally and being fed per os with a diet appropriate for her age; no oesophageal dilatation was necessary. Type A oesophageal atresias are long-gap forms: they are treated with direct anastomosis after the blind pouches come together spontaneously in the first four months of life. Stress is laid on the rarity of the case. According to Kluth's classification of 1976, this form was described by Mason in 1855 and Jlott in 1905 on the basis of autopsy findings. A review of the literature did not show any similar clinical cases.

Can CAP guideline adherence improve patient outcome in internal medicine departments?

The impact of compliance with Italian guidelines on the outcome of hospitalised community-acquired pneumonia (CAP) in internal medicine departments was evaluated. All Fine class IV or V CAP patients were included in this multicentre, interventional, before-and-after study, composed of three phases: 1) a retrospective phase (RP; 1,443 patients); 2) a guideline implementation phase; and 3) a prospective phase (PP; 1,404 patients). Antibiotic prescription according to the guidelines increased significantly in the PP. The risk of failure at the end of the firstline therapy was significantly lower in the PP versus the RP (odds ratio (OR) 0.83, 95% confidence interval (CI) 0.69-1.00), particularly in Fine class V patients (OR 0.71, 95% CI 0.51-0.98). Analysis of outcome in the overall population (2,847 patients) showed a statistically significant advantage for compliant versus noncompliant therapies in terms of failure rate (OR 0.74, 95% CI 0.60-0.90) and an advantage in terms of mortality (OR 0.77, 95% CI 0.58-1.04). Antipneumococcal cephalosporin monotherapy was associated with a low success rate (68.6%) and the highest mortality (16.2%); levofloxacin alone and the combination of cephalosporin and macrolide resulted in higher success rates (79.1 and 76.7%, respectively) and significantly lower mortalities (9.1 and 5.7%, respectively). Overall, a low compliance with guidelines in the prospective phase (44%) was obtained, indicating the need for future more aggressive and proactive approaches.

Context-dependent regulation of embryonic stem cell differentiation by mGlu4 metabotropic glutamate receptors

The mGlu5 receptor is the only metabotropic glutamate receptor subtype expressed by mouse embryonic stem (ES) cells grown under non-differentiating conditions [Cappuccio, I., Spinanti, P. Porcellini, A., Desiderati, F., De Vita, T., Storto, M., Capobianco, L., Battaglia, G., Nicoletti, F., Melchiorri, D., 2005. Endogenous activation of mGlu5 metabotropic glutamate receptors supports self-renewal of cultured mouse embryonic stem cells. Neuropharmacology 1, 196-205]. We now report that ES cells differentiating into embryoid bodies (EBs) progressively lose mGlu5 receptors and begin to express mGlu4 receptors at both mRNA and proteinc level. A 4-day treatment of EBs with the mGlu4 receptor agonist, L-2-amino-4-phosphonobutanoate (L-AP4), increased mRNA levels of the mesoderm marker, brachyury and the endoderm marker, H19, and decreased the expression of the transcript for the primitive ectoderm marker, fibroblast-growth factor-5 (FGF-5). These effects were prevented by the mGlu4 receptor antagonists, alpha-methylserine-O-phosphate (MSOP). Plating of EBs for 4 days in vitro in ITSFn medium induced cell differentiation towards a neural lineage, as reflected by the expression of the intermediate filament protein, nestin, and the homeobox protein, Dlx-2. Pharmacological activation of mGlu4 receptors during cell incubation in ITSFn medium increased the expression of both neural markers. Similar results were obtained when neural differentiation was induced by exposure of EBs to retinoic acid. These data suggest that differentiation of cultured ES cells is associated with changes in the expression pattern of mGlu receptors and that activation of mGlu4 receptors affects cell differentiation in a context-dependent manner.

Oral Manifestations of Langerhans Cell Histiocytosis in a Pediatric Population

Langerhans Cell Histiocytosis is a rare and protean disease of unknown etiology, clinically characterized by single or multiple osteolytic and/or soft tissue lesions. Oral involvement may predate systemic manifestations or mimic infectious/inflammatory disorders. In the present series, oral involvement characterized eight cases of pediatric Langerhans Cell Histiocytosis and oral symptoms represented a very early sign of this disease in four patients. A careful clinical investigation and a proper histologic analysis were required for achieving a definite diagnosis and for confirming clinical suspicion of disease relapse. Immunohistochemistry, that nowadays represents a reliable and accessible ancillary histological technique, allowed the definite diagnosis in all cases of our series.

Amino acid levels in some lethargic mouse brain areas before and after pentylenetetrazole kindling

Genetic animal models have contributed significantly to our understanding of epilepsy causes. Lethargic mice are considered a valid model of absence epilepsy, which have been shown to possess behavioral, electrographic and pharmacological profiles similar to those of humans with absence epilepsies. Single gene mutations that comprise the beta4 subunit of voltage-sensitive Ca2+ channels underlie the spontaneous discharges of the absence, non-convulsive seizures of lethargic mice. There are no available data concerning how the mutant channels actually behave at terminals in response to chemical activation by subconvulsant stimulation with pentylenetetrazole. In this study, we found no significant difference in the convulsive dose 50 between lethargic and control mice. Lethargic mice showed a more rapid development of kindling to pentylenetetrazole than control animals. No significant differences were observed between the groups of mice rechallenged with pentylenetetrazole 30 or 60 days after the end of the chronic treatment. Marked differences in brain amino acid levels were found between the two strains of mice in basal conditions and after kindling. In conclusion, our results indicate that lethargic mice show a range of biochemical and behavioral changes, correlated in particular with a higher susceptibility to develop kindled seizures.