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Measurements aimed at investigating the quenching of sensitivity of Gafchromic EBT3 films irradiated with charged particles at radiotherapy energy levels have been carried out. Films have been irradiated with beams of protons and carbon ions of interest for Hadron Therapy. The broadening of pencil beams in water phantom as a function of initial energy has been studied and the quenching of EBT3 film sensitivity has been quantified. A procedure for correcting the dose images obtained by means of EBT3 films has been improved and its application to an irradiation test has show the validity of the proposed methodology.

Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measurements performed at various times after irradiation only reveal the slow changes due to the auto-oxidation effect, proving therefore that the modality of chelation of ferric ions by xylenol orange can affect the observed changes in the optical absorbance spectra.

The quenching of sensitivity of non-gaseous dosimeters exposed to charged particles was studied, in particular with reference to gel dosimeters and gafchromic EBT3 films. The studies were focused to dosimetry for Hadron Therapy and boron neutron capture therapy (BNCT). A correction coefficient can be more easily determined for BNCT dosimetry, while it is complex to correct the dosimeter response in the case of charged particle beams for Hadron Therapy. A proposed method for correcting the measured images is in continuous development.

Studies of the beam broadening and in-depth dose profiles in water for a pencil beams of protons and carbon ions, with energies in the range of interest for Hadron Therapy, have been carried out. Transversal images of absorbed dose have been attained and fitted with Gaussian approximation. The area of the section at half height of the fitting surface was evaluated to quantify the beam broadening. The radius R of the section was taken to describe the beam broadening and a mathematical function giving R versus depth in water, for whichever PB energy, was attained, both for protons and for carbon ions.

Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measurements performed at various times after irradiation only reveal the slow changes due to the auto-oxidation effect, proving therefore that the modality of chelation of ferric ions by xylenol orange can affect the observed changes in the optical absorbance spectra.

Introduction Fricke gel dosimeters allow measurements of 3D dose distributions and can be an effective tool for dosimetry verifications in radiotherapy. Various authors have reported drawbacks of the gels affecting the accuracy in case of low dose measurements. Purpose This study aims at investigating such drawbacks and at establishing the conditions for an optimal use of the gels. Materials and methods Our dosimeters consist of gels infused with a Fricke ferrous sulphate solution combined with xylenol orange (XO). Two kinds of xylenol orange (XO) and two different gelling agents (gelatin from porcine skin and Agarose) were utilized. Gels are red out by light absorption techniques: images of absorbance in two wavelength regions (around 430 nm and 585 nm) are acquired with a CCD camera. Absorbance spectrum measurements were done with a compact spectrometry based on optical fibres. Magnetic resonance (MR) measurements of Longitudinal Relaxation Time (T1) were also performed. Results Different trends characterized the absorbance spectra of dosimeters obtained with different gelling agents or different XOs. Moreover, the trends were different for different absorbed doses and varied over a few hours after irradiation. Conclusion The variation of the absorbance spectra is consistent with various previously unexplained effects reported in literature and may explain them. The results are a valid aid for a better use of these dosimeters and warrant further studies of the changes in the Fricke gel matrices after irradiation. Disclosure Authors declare no relationship that may bias the presentation.

Ebstein anomaly is a rare congenital heart defect that most often occurs sporadically within a kindred. Familial cases, although reported, are uncommon. At this time, the genetic etiology of Ebstein anomaly is not fully elucidated. Here, we describe clinical and molecular investigations of a rare case of familial Ebstein anomaly in association with a likely pathogenic mutation of the MYH7 gene. The severity of presentation varies, and Ebstein anomaly can be observed in association with such other heart defects as ventricular septal defect and left ventricular (LV) hypertrabeculation, as seen in our family of study. In our family of study, the 31-year-old father and four of his children have been diagnosed with Ebstein anomaly. Genetic testing revealed that the father was heterozygous for the Glu1220del variant detected in exon 27 of the MYH7 gene. The MYH7 gene encodes the β-myosin heavy chain and is expressed in cardiac muscle. DNA sequencing of three of his affected children confirmed that they carried the same variant while the fourth affected child was not available for testing. This is the first report of familial Ebstein anomaly associated with the Glu1220del mutation of the MYH7 gene. The mutation segregates with disease in a family with autosomal dominant transmission of congenital heart defects including Ebstein anomaly and other associated cardiovascular defects including LV hypertrabeculation and ventricular septal defect.

Acute liver failure (ALF) is defined as a severe, sudden liver dysfunction that induces encephalopathy and coagulopathy (prothrombin time [PT/INR] > 1.5) within 26 weeks of the onset of symptoms (usually jaundice) in patients without previous liver disease. Quantitative and qualitative platelet dysfunction, reduced synthesis of clotting factors, increased consumption of factors (mainly II, V, VII, X), reduced clearance of both activated factors, and/or factor inhibitor complexes are among the most important proposed pathogenetic factors. A possible role might be also played by the diminished degradation of anticoagulants. Plasminogen activator inhibitor 1 (PAI-1) is increased, shifting the balance toward hypofibrinolysis, despite the elevated levels of tissue plasminogen activator (tPA). Although changes in coagulation parameters provide crucial information for the management of the patient with ALF, the optimal management of the hemostatic defects is far from being defined. Because spontaneous bleeding occurs rarely during ALF, measures to improve the bleeding diathesis (fresh frozen plasma, cryoprecipitate, platelet transfusion) are recommended only in patients with clinically significant bleeding or before placement of invasive devices. Antifibrinolytic drugs are used in some cases, but often empirically. The role of rFVIIa, even if promising, is still under debate.

Kidney transplantation is now recognized as the treatment of choice for patients with chronic renal failure. Despite the extension of indications to patients suffering severe hypertension, ischemic heart disease, and chronic heart failure, the worldwide results are superb. However, perioperative cardiac complications occur in 6% to 10% of transplanted patients. Aggressive intraoperative volume expansion is still recommended to maximize graft functional recovery (up to 30 mL/kg/h, central venous pressure [CVP] > 15 mm Hg), but patients with preexistent cardiac disease or poor myocardial function are exposed to the risk of fluid overload, acute respiratory failure, and prolonged ventilation. Among the last 90 cases performed at our institution, good functional recovery of the graft was present in 94% of the patients within 2 weeks, despite a much more conservative intraoperative hydration policy (crystalloids 2400 +/- 1000 mL, 15 mL/kg/h, CVP 7-9 mm Hg). Graft failure which occurred in 5 patients was significantly correlated only with donor age, while perioperative cardiovascular complications had been present in 9 cases (10%) who were coronary artery disease patients (55%). Age above 50 years was the only significant risk factor. Supranormal volume loading is probably not always warranted in kidney transplantation.

This study compares ropivacaine and levobupivacaine when administered for cervical plexus block. The authors therefore compared the arterial pressure profile and the incidence of hypotension between drugs.Forty-eight patients scheduled for carotid artery surgery (American Society of Anesthesiologists [ASA] 2-3) were randomly assigned to receive levobupivacaine or ropivacaine (24 patients each). Neurological status, arterial pressure profile and control of postoperative pain were the main observed parameters. All patients had severe carotid stenosis (80%) and/or had suffered transient ischemic attacks (TIAs) or preoperative strokes. The same team performed anesthesia and surgery for carotid endarterectomy; the cervical block was performed according to Moore's technique.Arterial pressure, heart rate and S(a)O(2p) were monitored continuously with particular regard to T0 (baseline), T1 (immediately before carotid clamping), T2 (immediately before declamping) and T3 (at the end of the procedure). Hypotension was defined as the fall of arterial systolic pressure 30% below baseline or less than 100 mmHg.Arterial pressure fell significantly in both groups at T1 with respect to T0 (P0.0001). Levobupivacaine patients showed higher mean arterial pressure on T0 (112+/-12 mmHg versus 103+/-7 mmHg; P0.05), thus suggesting a more pronounced vasodilator effect, as confirmed by the larger drop of arterial diastolic pressure (P=0.007). An absolute 6% difference of hypotension-related drug was recorded with levobupivacaine (19%) as compared with ropivacaine (13%) (P=0.28).Levobupivacaine has a greater vasodilatory effect than ropivacaine. Its higher incidence of hypotension, although not statistically significant, suggests ropivacaine as the drug of choice for cervical plexus block.

Background Indwelling central venous catheters (CVCs) are essential devices in the management of patients with hematological disorders treated with chemotherapy. However, their nature predisposes patients to unwanted complications. Methods CVC-related complications were retrospectively analyzed in 227 hematologic patients who were consecutively admitted to our hematology department between May 2002 and April 2004. Patients’ diagnoses comprised acute myeloid leukemia (36.8%), acute lymphoid leukemia (7.3%), lymphoproliferative disorders (28.3%), multiple myeloma (19.5%), myeloproliferative syndromes (5%) and others (3.1%). The CVCs used were polyurethane three lumen 7-Fr (111 patients) for chemotherapy and 12-Fr (114 patients) for chemotherapy and peripheral blood stem cell apheresis, plus two tunneled catheters. Results The pathological events were: bacteriaemias (n=46); occlusions (n=10); exit tunnel infections (n=8); thrombosis (n=6); lung emboli (n=2). Among febrile patients the bacteriemia frequency was 20%, of which 13.6% were CVC-related (with a higher incidence in leukemia patients (p=0.027). Among the isolates, gram-positive bacteria were found in 29 cases (23 CVC-related cases), and gram-negative bacteria in 16 cases (8 CVC-related cases). Only one patient had Candida albicans sepsis. At univariate and multivariate analysis significant risk factors for infection (pConclusions In our hematologic patients, the CVC complications were mainly septic, with only 10.1% of CVC-related bacteriemias, despite prolonged catheterization duration. Acute leukemia patients were at major risk for sepsis, probably due to a more severe neutropenia and prolonged catheterization duration.

A three month old male calf showed the symptoms of anuria with ascites and high blood levels of urea. Post mortem examination revealed a haematoma of the urethral wall which by obstructing the lumen had caused the urinary bladder rupture and the resultant uroperitoneum.