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Ruta chalepensis L. (Rutaceae) leaf extract was investigated for its chemical profile and antioxidant and hypoglycaemic properties. The antioxidant effects were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene bleaching, and metal chelating activity assays. The carbohydrate-hydrolysing enzymes inhibition assay was used to test the hypoglycaemic potential. R. chalepensis showed a high content of hesperidin and rutin with values of 591.9 and 266.7 mg/g dry extract, respectively. The extract exhibited a promising protection of lipid peroxidation (IC50 value of 16.9 µg/mL) and inhibited both α-amylase and α-glucosidase enzymes in a concentration-dependent manner. The highest activity was found against α-amylase (IC50 value of 69.0 µg/mL). The obtained results support the use of R. chalepensis leaves as healthy food ingredients.

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AIM: The force-frequency relationship (F-FR) is an important intrinsic regulatory mechanism of cardiac contractility. The involvement of autonomic nervous system in this physiological aspect of cardiac control remains unclear. The aim of the study was to evaluate the role of extrinsic and intrinsic cardiac adrenergic innervations on the heart rate (HR)-related positive inotropic response. METHODS: Twenty-four dogs were anesthetized and acutely instrumented to monitor and record ECG, systemic and left ventricular pressures and derivatives, and to pace the heart at 130, 150, 170, 190 and 210 bpm, in order to construct the F-FR curve. Animals were randomly assigned to four groups (n = 6 each): vehicle (V), ganglion-blocked (G-B), ß-blocked (ß-B) and ganglion-blocked plus ß-blocked (G-B + ß-B). RESULTS: Vehicle treated animals presented the classical F-FR. In the ß-B group F-FR was blunted, but never fully suppressed. The G-B treated animals showed a bell-shape response curve of the induced inotropic effect with the zenith at 170 bpm: the first part of the curve resembling the control one, followed by a rapid decline toward baseline value. The co-administration of G-B and ß-B agents reversed the contractile response to HR rise with a curve resembling the negative F-FR curve observed in the failing heart. CONCLUSION: The F-FR appeared to be constituted by two consecutive mechanisms: first depolarization-rate dependent, and a second catecholamine-dependent. The natural consequence of these observations is that the full expression of F-FR needs an intact adrenergic system.

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Cardiac imaging with gated single-photon emission computed tomography (SPECT) allows the evaluation of myocardial perfusion and analysis of global and regional left ventricular function. Gated SPECT is a validated and established diagnostic and prognostic method for evaluation of patients with suspected and known coronary artery disease. Significant improvements in software and gamma camera technology in SPECT cardiac imaging have been obtained. New detectors open a scenario for faster imaging with lower radiation dose to the patient. Appropriate use of the SPECT imaging is regulated by evidence-based guidelines and appropriateness criteria as well as by third-party payers in an effort to restrain the unsustainable growth of imaging testing recently observed. Future of cardiac SPECT imaging will be driven by societal demand for cost effective, accurate, and safe testing, which will improve meaningfully patients' management and outcomes.

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A rapid microwave procedure for protein hydrolysis coupled with High Performance Anion Exchange Chromatography and Pulsed Amperometric Detection (HPAEC-PAD) was developed to quantify the amino acid 4-hydroxyproline in meat and meat-based products. This innovative approach was successfully applied to determine collagen content (4-hydroxyproline×8) as the index quality of meat material employed in the preparation of typical meat sausages ("Mortadella di Bologna PGI" and "Salamini italiani alla cacciatora PDO") and fresh filled pastas. Microwave hydrolysis showed a precision and accuracy similar to traditional hydrolysis (RSD% from 0.0 to 6.4; relative error 1.4-10.0%) with a reduction in the hydrolysis time from 24h to 20min. HPAEC-PAD allowed detection of 4-hydroxyproline without pre or post-column derivatization and the use of non-toxic eluents.

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BACKGROUND AND OBJECTIVES: Faecal calprotectin is predictive of clinical relapse in inflammatory bowel disease and ultrasound is sensitive in detecting its post-surgical recurrence. However, no data regarding the role of calprotectin in predicting post-surgical recurrence in asymptomatic Crohn's disease are available. The aim of this study was to prospectively evaluate the role of calprotectin as a predictive marker for one year post-surgical endoscopic recurrence in comparison with ultrasound in patients with asymptomatic Crohn's disease. MATERIAL AND METHODS: We consecutively enlisted 50 patients who had undergone a resection for Crohn's disease. Faecal calprotectin was analysed and ultrasound were performed at the third month, and a colonoscopy after one year. The sensitivity and specificity of these two techniques were evaluated using endoscopic findings as a golden standard. A Receiver Operator Curve (ROC) curve was plotted, in order to identify the best-cut off value for calprotectin. RESULTS: 39 out of 50 patients were evaluated by performing a colonoscopy after one year; 19 patients had an endoscopic recurrence after one year. Calprotectin sensitivity and specificity were calculated for 5 different cut-off values; the best cut-off value for calprotectin sensitivity (63%) and specificity (75%) was > 200 mg/L. The US sensitivity and specificity at the third month were 26% and 90% respectively. CONCLUSIONS: When performed three months after surgery ultrasound is more specific than calprotectin in predicting endoscopic recurrence. Faecal calprotectin at a dosage > 200 mg/L seems to have a better sensitivity than ultrasound. Values of calprotectin > 200 mg can be an indication to colonoscopy in the group of patients with negative ultrasound in order to detect early recurrence.

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BACKGROUND: Crohn's disease (CD) is frequently associated with extra-intestinal manifestations (EIMs) and infliximab has been recently proposed for the treatment of CD with EIMs. Our aim was to evaluate the short-term efficacy of infliximab in this treatment. PATIENTS AND METHODS: Thirty CD patients were treated with infliximab. Fifteen patients (50%) showed EIMs before starting therapy. Ten patients presented an arthritis (five sacroiliitis, five spondylitis), with six also reporting peripheral arthralgias. Four patients presented cutaneous EIMs while three patients had an ocular EIM. RESULTS: At week 10, all patients reported an improvement in EIMs. Regarding arthritis, ASAS20 and ASAS40 improvement was observed in 80% and 60% of patients, respectively. In the four patients with cutaneous EIMs and in the three with ocular EIMs, complete healing was observed. Recurrence was observed in 10 out of 15 patients (66%) and a second course of treatment with infliximab was required. This proved to be effective in all cases except for one patient who stopped treatment because of a severe adverse reaction. CONCLUSIONS: Infliximab is an effective drug in the short-term treatment of EIMs complicating CD. Although relapse of EIMs occurs frequently, retreatment ensures effective control of the symptoms.

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The accuracy of dose delivery in radiotherapy is affected by the uncertainty in tumor localization. Motion of internal anatomy due to physiological processes such as respiration may lead to significant displacements which compromise tumor coverage and generate irradiation of healthy tissue. Real-time tracking with infrared-based systems is often used for tracking thoracic motion in radiation therapy. We studied the origin of ghost markers ("crosstalk") which may appear during dual sensor-based infrared tracking of independent reflective markers. Ghost markers occur when two or more reflective markers are coplanar with each other and with the sensors of the two camera-based infrared tracking system. Analysis shows that sensors are not points but they have a finite extent and this extent determines for each marker a "ghost volume." If one reflective marker enters the ghost volume of another marker, ghost markers will be reported by the tracking system; if the reflective markers belong to a surface their "ghost volume" is reduced to a "ghost surface" (ghost zone). Appearance of ghost markers is predicted for markers taped on the torso of an anthropomorphic phantom. This study illustrates the dependence of the shape, extent, and location of the ghost zones on the shape of the anthropomorphic phantom, the angle of view of the tracking system, and the distance between the tracking system and the anthropomorphic phantom. It is concluded that the appearance of ghost markers can be avoided by positioning the markers outside the ghost zones of the other markers. However, if this is not possible and the initial marker configuration is ghost marker-free, ghost markers can be eliminated during real-time tracking by virtue of the fact that they appear in the coordinate data sequence only temporarily.

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BACKGROUND: Crohn's disease (CD) frequently involves the small bowel. Actually, the diagnosis of CD is made by ileocolonoscopy (IC) and small bowel enteroclysis (SBE), while trans-abdominal bowel sonography (BS) and Tc-99m-HMPAO leukocyte scintigraphy (LS) are only partially used in spite of their minimal invasiveness. AIM: to compare the diagnostic accuracy of these procedures for the diagnosis of small bowel CD. PATIENTS AND METHODS: in about two years a series of consecutive subjects underwent IC, SBE, BS and LS for either suspected or known small bowel CD. RESULTS: Sensitivity, specificity, positive and negative predictive value for CD diagnosis of the studied procedures were respectively: 98%, 97%, 98% and 97% for SBE; 92%, 97%, 98%, and 88% for BS; 90%, 93%, 96% and 85% for LS. In addition, the parallel combined use of BS and LS led to overall sensitivity, specificity, positive and negative predictive value of 100%, 93%, 96%, 100%, respectively. CONCLUSION: SBE, BS and LS are accurate procedures for the diagnosis of small bowel Crohn's disease. The use of BS and LS, particularly in combination, can be proposed as early diagnostic approach to subjects with a suspicion of disease.

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Ultrasound (US) image-guided patient positional verification was performed daily on four prostate cancer patients using the BAT system (NOMOS Corporation, CA). The BAT system has shown that the prostate can shift by as much as 1 cm from its intended position in any direction. Furthermore, the daily shifts measured by the BAT system were included into the treatment planning system to assess changes in prostate dose coverage. Dose volume histograms were used to compare the dosimetry between the ideal patient set-up situation (prostate always positioned correctly) and that taking all patient daily shifts into consideration. Daily patient shifts on the order of magnitudes measured, can significantly and adversely affect dosimetric coverage, therefore an US-based patient positioning system is required for improving the therapeutic ratio.

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A semi-automatic technique for the direct setup alignment of radiosurgical circular fields from an isocentric linac to treatment room laser cross-hairs is described. Alignment is achieved by acquiring images of the treatment room positioning laser cross-hairs superimposed on the radiosurgical circular field image. An alignment algorithm calculates the center of the radiosurgical field image as well as the intersection of the laser cross-hairs. This determines any alignment deviations and the information is then used to translate the radiosurgical collimator to its correct aligned position. Two detectors, each being sensitive to the lasers and ionizing radiation, were used to acquire the radiation/laser images. The first detector consists of a 0.3-mm-thick layer of photoconducting a-Se deposited on a 1.5-mm-thick copper plate and the second is film. The algorithm and detector system can detect deviations with a precision of approximately 0.04 mm. A device with gyroscopic degrees of freedom was built in order to firmly hold the detector at any orientation perpendicular to the radiosurgical beam axis. This device was used in conjunction with our alignment algorithm to quantify the isocentric sphere relative to the treatment room lasers over all gantry and couch angles used in dynamic stereotactic radiosurgery.

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A feasibility study has been performed on metal/amorphous selenium detectors for megavoltage portal imaging. The metal plates of the detectors were positioned facing the incident 6 MV and Co-60 photon spectra. The detectors consist of various thicknesses (0.15 mm, 0.30 mm, and 0.50 mm) of amorphous selenium (a-Se) deposited on metal plates of varying thicknesses: aluminum (2.0 mm), copper (1.0 mm and 1.5 mm), stainless steel (0.9 mm), or glass (1.1 mm). The detectors were charged prior to irradiation by corona methods, and the portal images were subsequently digitized after irradiation with a noncontact electrostatic probe. The sensitivity of the detectors to dose, electric field across the a-Se layer, metal plate type and a-Se thickness, was studied. The electrostatic voltage remaining on the a-Se layer was found, both theoretically and experimentally, to exhibit a cubic relationship with respect to dose. An increase in electric field increases the sensitivity (gradient of the a-Se surface voltage vs dose curve) and dynamic range of the resultant image. An increase in a-Se thickness, however, although also increasing the sensitivity, decreases the dynamic range. The metal plate types and thicknesses within the range studied do not have a significant effect on detector sensitivity. Image quality and contrast resolution of the detector were evaluated with a contrast-detail phantom and compared to commercially available film based and electronic portal imaging devices. Image quality of the metal/a-Se detector as a function of dose was studied by discharging the a-Se to various fractions of its initial charge, and as expected, increases with dose due to a decrease in quantum noise. Contrast-detail images obtained by metal/a-Se detectors are superior to those obtained at higher dose levels by other commercial systems.

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Measurements of modulation transfer function (MTF) for front and back metal-plate/film portal detectors are reported for the Cobalt-60 and 10 MV spectra. The detectors consist of a double-emulsion portal film secured between plates of Al, Cu, brass, or Pb with thicknesses varying from 0 to 4.81 mm. Secondary electrons produced within the front plate generate the main signal, but the MTF decreases with an increase in front plate thickness greater than the maximum range of electrons Rmax because of photon scatter in the front plate. Because the decrease of MTF with backplate thickness ceases for backplate thickness greater than Rmax, the MTF is influenced more by the backscatter electrons than the backscatter photons.

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Noise power spectrum (NPS) and detective quantum efficiency (DQE) for metal-plate/film portal detectors are reported for the Co-60 and Linac 10 MV spectra. The detectors consist of a double-emulsion portal film secured between plates of aluminum, copper, brass, or lead. The NPS was found to be independent of the detector sensitivity demonstrating that the film grain noise dominates over the quantum noise. Although the detector signal increases with density of the backplates, the resultant electron-backscatter increases detector blur, thus decreasing the DQE. The lowest DQEs are therefore produced with the lead backplates, irrespective of the front plates. For a given backplate and for front-plate thicknesses less than the maximum electron range, the DQE increases with density of the front plate.

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