Biomedical subjects

C De Angelis

Publications and source records attributed to C De Angelis.

At least 19 recordsLinked to original sources

PubMed2006

Multicentre retrospective study on endoscopic ultrasound complications.

BACKGROUND: Endoscopic ultrasonography, both conventional and interventional, has been used increasingly during the past 20 years and is deemed a safe technique. Its complication rate, however, has been studied to only a limited extent. This multicentre investigation sought to establish the complication rate for a large number of endoscopic ultrasonography procedures. METHODS: By means of a questionnaire, we collected data from six centres on the number of endoscopic ultrasonography examinations performed and divided them into conventional and interventional examinations of the upper and lower gastrointestinal tract. Information was obtained on technical modalities such as instruments and sedation and, for interventional endoscopic ultrasonography, indications, pre-procedural exams and technical details (needle calibre, number of passes) had to be specified. Complications were classified as mild, moderate, severe or fatal and their onset as immediate, early or late. Variables that entered into the analysis of complication rate included type of endoscopic ultrasonography instrument used, type and site of lesion biopsied, number of needle passes and operator experience. RESULTS: Eleven thousand five hundred thirty nine endoscopic ultrasonographic procedures were reported, of which 10,731 were conventional and 808 interventional. No deaths occurred; there were 14 (0.12%) complications, 5 (0.046%) of them following conventional endoscopic ultrasonography and 9 (1.11%) after interventional endoscopic ultrasonography. Seven complications were mild, four moderate and three severe. CONCLUSIONS: Both conventional and interventional endoscopic ultrasonography were confirmed to be acceptably safe techniques.

Endoscopy, Digestive System↗

PubMed2006

On measuring the output of an IORT mobile dedicated accelerator.

In the present work, dose-to-water values derived from Fricke (operated by the Italian Primary Standard Dosimetry Laboratory) and alanine (operated by the Istituto Superiore di Sanità, Italy) measurements in IORT electron beams characterised by a high dose per pulse were compared to show the extent of equivalence of the two dosimetry systems. This study demonstrates agreement (within 2%) of the two dosimetry systems for plane-base IORT applicators, but in the case of small diameter (40 mm) and bevelled (22.5 degrees ) applicators, Fricke dosemeters underestimated doses by 2.4%. For base bevelled IORT applicators (22.5 degrees or more) with small diameter ( approximately 40 mm or less) reduced dimensions of the dosemeter are needed. Under these measurement conditions, the alanine dosemeter gives better accuracy in beam output determination compared with the Fricke dosemeter used.

Equipment Failure Analysis↗

PubMed2006

Use of commercial alanine and TL dosemeters for dosimetry intercomparisons among Italian radiotherapy centres.

In the implementation of a large-scale dosimetry intercomparison one of the main constraints is the availability of large number of dosemeters of the highest quality. Therefore, ISS tested the possibility of using commercially available dosemeters, alanine pellets and thermoluminescence (TL) dosimetry chips, for transfer dosimetry within the Italian intercomparison programme. In this work the characterisation of commercial alanine and TL dosemeters along with the ISS dose assessment procedure used in the Italian intercomparison are reported. Results demonstrate the feasibility of the ISS approach to transfer dosimetry since it is possible to measure 10 Gy with a combined uncertainty of 1% (1sigma) and 1 Gy with a combined uncertainty of 1.7% (1sigma) with alanine and TL dosemeters, respectively.

Alanine↗

PubMed2006

Improvements in CVD diamond properties for radiotherapy dosimetry.

The goal of this work was to compare the behaviour of a chemical vapour deposited (CVD) diamond sample, grown at the University of Florence using a local procedure, with that of a commercial CVD diamond. The comparison was performed exposing both systems to 25 MV photons and measuring the current response during irradiation. Properties of dosimetric interest such as stability of response, dose rate dependence and rise time were investigated. After a preliminary study, which evidenced better performances of the commercial device with respect to the local CVD diamond, the latter was irradiated with a high fluence of fast neutrons. As a result of the neutron treatment, the quality of the CVD home-made diamond has been improved to match with that of the commercial dosemeter.

Diamond↗

PubMed2006

Emergency catheter probe endoscopic sonography (CP-EUS): an effective procedure in the assessment of a bleeding gangliocytic paraganglioma.

Catheter probe endoscopic sonography is a relatively rapid and safe procedure, carried out during standard endoscopy, capable of distinguishing solid from cystic lesions and vascular from avascular masses. Herein we discuss the role of catheter probe endoscopic sonography in the emergency assessment of a patient with recent and severe bleeding from an ulcerated polyp, arising from the papilla. During the endoscopy, catheter probe endoscopic sonography showed the solid and submucosal nature of the lesion, suggesting its localised and benign nature and, most importantly, demonstrating the high risk of rebleeding from vascular structures communicating with the ulcer. Because of this finding three metallic endoclips were positioned. The lesion was not removed endoscopically because of its difficult position and the high risk of haemorrhage. The mass, removed through a duodenotomy, was shown to be a gangliocytic paraganglioma, an uncommon tumour, frequently resulting in surgery because of abdominal pain and gastrointestinal bleeding.

Adult↗

PubMed2006

Diagnosis of acute foetal distress does not preclude banking of umbilical cord blood units.

Clinical diagnosis of acute foetal distress (AFD) is based on several parameters such as abnormal foetal heart rate (FHR) pattern and/or meconium liquid staining (MLS). Standards for cord blood (CB) banking indicate that AFD should be considered as exclusion criteria for CB collection, but precise guidelines on how to proceed with CB collection in the presence of AFD signs during labour are not available. We evaluated whether the presence of FHR abnormality and/or MLS during labour 1) reduced the CB collection activity; 2) were associated with the infant's acidaemia or asphyxia and 3) deteriorated the biological characteristics of CB units. Thirty-three units of CB were evaluated for biological parameters, gas values and newborn's Apgar score. The results were compared with a control group of 33 consecutive units previously banked. No differences were observed between the two groups and all but one newborn showed normal Apgar score and absence of metabolic acidaemia. The results showed that 1) AFD reduced the CB collection activity by 10% each year; 2) the majority of CB units collected in the presence of abnormal FHR and/or meconium have biological characteristics eligible for banking; 3) FHR alterations or meconium in the presence of normal gas analysis do not represent certain diagnosis of AFD.

Apgar Score↗

PubMed2006

[Invasive diagnosis of Helicobacter pylori infection in the 2006 clinical practice].

Currently, different approaches are employed to detect the presence of Helicobacter pylori (H. pylori): invasive, if based on biopsies performed during endoscopy (urease test, histology, culture, polymerase chain reaction), and non-invasive, if endoscopy is not carried out. Another option is offered by the invasive non-endoscopic methods (string test). An update on the diagnostic invasive approaches to patients in the clinical setting is presented in this review. Although non-invasive tests are preferred, important information can be gained from histology, the unique technique which permits the evaluation of the status of the mucosa, and from culture, that allows strain typing and tests for antibiotic susceptibility. Until today, polymerase chain reaction has had a limited application in the clinical practice and the role of non-endoscopic methods needs to be better clarified in the future.

Bacteriological Techniques↗

PubMed2006

Levobupivacaine and ropivacaine in the infraclavicular brachial plexus block.

AIM: Infraclavicular brachial plexus block were first described by Raj, yet this block remained underutilized despite theoretical advantages. The aim of this prospective, randomized study was to compare equipotent doses of levobupivacaine and ropivacaine. METHODS: For this prospective, randomized study we have enrolled, after informed consent, 30 patients of both sexes, ASA status I-II, who were going to receive surgery to the forearm or hand with tourniquet position on the arm. The infraclavicular plexus block was performed by using vertical technique. The block was performed with 30 mL of levobupivacaine 0.5% or ropivacaine 0.75%. RESULTS: No differences were reported between 2 groups in terms of demographic data. The onset-time for motor block was greater for ropivacaine group (p<0.05); the sensitive block was longer in levobupivacaine group (p<0.05). CONCLUSIONS: The long duration of sensory block associated with the with good analgesia, less toxicity and the pharmacodynamic properties of levobupivacaine include this new local anaesthetic as a valid choice respect other local anaesthetic for infraclavicular plexus block.

Amides↗

PubMed2006

Zollinger-Ellison syndrome in 2006: concepts from a clinical point of view.

Zollinger-Ellison syndrome (ZES) is characterised by peptic ulcers of the upper gastrointestinal tract failing to heal despite maximal medical therapy, diarrhoea and marked gastric acid hypersecretion associated with a gastrin-secreting tumour (gastrinoma). ZES might be associated with multiple endocrine neoplasia type 1. The main diagnostic features are hypergastrinemia and acid hypersecretion. When these parameters give borderline results, provocation test (with secretin or calcium) may be required. To identify the localisation of gastrinoma several imaging techniques have been proposed. Somatostatin receptor scintigraphy is capable to localise the tumour in 80% of the cases and to identify it even in anatomic sites other than pancreas and duodenum. Endoscopic ultrasonography has a sensitivity as high as 79-93% and a specificity of 93%. The 2 main principal therapeutic strategies are to control both the gastric acid hypersecretion and the growth of the neoplasia. Proton pump inhibitors (PPIs) are the drugs of choice for patients with ZES. Furthermore, safety of PPIs in the maintenance therapy has been proven both in short- and in long-term studies. The best surgical treatment is excision of gastrinoma before metastatic spread has occurred. Somatostatin-analogues can reduce both gastric acid hypersecretion and serum gastrin levels. Moreover, they have an antiproliferative effect. Chemotherapy, interferon and embolisation are indicated in rapidly evolving tumours or in cases in which the tumoral symptoms cannot be treated by other approaches.

Antineoplastic Agents↗

PubMed2005

Delivery of radiofrequency energy to the gastroesophageal junction (Stretta procedure) for the treatment of gastroesophageal reflux disease.

BACKGROUND: Radiofrequency (RF) energy treatment is increasingly offered before invasive surgical procedures for selected patients with gastroesophageal reflux disease (GERD). METHODS: Thirty-two patients undergoing the Stretta procedure were prospectively evaluated with upper endoscopy, manometry, 24-hour pH testing, SF-36 surveys, and GERD-specific questionnaires (GERD HRQL). RESULTS: Significant clinical improvement was observed in 91% of patients (29/32). Mean heartburn and GERD HRQL scores decreased (p = 0.001 and p = 0.003, respectively), and physical SF-36 increased (p = 0.05). At a minimum follow-up of 12 months, median esophageal acid exposure decreased (p = 0.79) and was normalized in eight patients. Median lower esophageal sphincter (LES) pressure was unchanged. Esophagitis healed in six of eight patients, but two patients with nonerosive disease developed asymptomatic grade A esophagitis during follow-up. At 12 months, 56% of patients were off proton pump inhibits. Morbidity was minimal. CONCLUSIONS: RF delivery to LES is safe and significantly improves symptoms and quality of life in selected GERD patients.

Electric Stimulation Therapy↗

PubMed2005

Use of alanine for dosimetry intercomparisons among Italian radiotherapy centers.

A pilot program of postal dosimetry intercomparison among 16 Italian Radiotherapy Centers was performed using the ISS Alanine/EPR dosimetry as a transfer system. Dosimeters were irradiated at 10 Gy with high-energy photon beams, both in reference condition in a water phantom and in an anthropomorphic phantom during the simulated treatment of rectum cancer. Intercomparison design along with alanine performances analyzing the different contributions to the combined uncertainty in dose assessment are reported. Main results of the pilot intercomparison, terminated in 2002, are also presented.

Alanine↗

PubMed2005

Giant fibrovascular polyp of the esophagus.

Giant fibrovascular polyps are uncommon benign esophageal tumors almost always originating from the cervical esophagus, frequently from the upper esophageal sphincter. The case of a 74-year-old man with a long history of dysphagia and a weight loss of 9 kg is presented. Neither barium esophagogram, computed tomogram or magnetic resonance imaging correctly evidenced the lesion. Only fiberoptic endoscopy suggested the correct diagnosis because the mass fluctuated endoluminally with the spasm of vomiting. A left cervical exploratory incision with esophagotomy was performed following the experience of two previous similar cases. A giant fibrovascular polyp was observed and excised. If a malignant or benign extensive intramural tumor had been identified, a total esophagectomy would have been performed. In our opinion the possibility of the presence of a fibrovascular polyp should always be considered in the presence of an undetermined esophageal mass, and in these cases a left cervical incision is the preferred surgical access. Once the correct diagnosis is established, a major esophageal resection should always be avoided.

Aged↗

PubMed2005

How accurate is the culture of Helicobacter pylori in a clinical setting? An appraisal.

AIM: The trend towards increasing prevalence of Helicobacter pylori (H. pylori) antibiotic resistance may jeopardize the efficacy of most regimens. Culture of the bacterium, the useful method able to address therapy, is influenced by various factors. Thus, validation of the procedure is fundamental. Most studies have been carried out in microbiological settings, while only few have been conducted in clinical frames. We evaluated the accuracy of culture for detection of H. pylori in a clinical dedicated laboratory. METHODS: Forty-six patients (28 females, 18 males, mean age 56+/-4.7 years) were included. Thirty experienced failure to H. pylori eradication after at least 3 courses of treatment. The control group included 16 subjects suffering from gastroesophageal reflux disease and negativity for H. pylori infection. Diagnostic strategy was based on histology, culture testing, serology and 13C-urea breath test. A patient was considered infected if 2 tests were positive. A commercial culture medium in microaerophilic atmosphere was utilized. RESULTS: Out of 30 positive specimens, culture correctly identified 29. In 1 case, no growth of micro-organisms occurred. In the control group, bacterial culture accurately identified all negative samples. One of them indicated growth but neither aspect nor confirmation tests identified H. pylori. Sensitivity was 96.7%, specificity 100%, and accuracy 97.8%. Positive and negative predictive values were 100% and 94.1%, respectively. CONCLUSIONS: Culture of H. pylori is a feasible method and provides a good level of diagnostic accuracy even in a clinical setting by following international guidelines combined with training of specialized personnel.

Breath Tests↗

PubMed2004

Levobupivacaine versus ropivacaine in psoas compartment block and sciatic nerve block in orthopedic surgery of the lower extremity.

AIM: The aim of this study was to compare the clinical profiles of psoas block and sciatic nerve block performed with either 0.5% levobupivacaine or 0.75% ropivacaine. METHODS: With ethical committee approval and written informed consent 80 ASA physical status I-II patients, undergoing lower extremity surgery received intravenous premedication with midazolam (0.05 mg/kg) and atropine (0.01 mg/kg). Patients were randomly allocated to receive a lumbar plexus block with: Levobupivacaine Group (L) 30 ml of 0.5% levobupivacaine or Ropivacaine Group (R) 0.75% ropivacaine, and sciatic nerve block with: Group R 10 ml 0.75 ropivacaine or Group L 0.5% levobupivacaine. The onset time and duration of nerve block were evaluated. RESULTS: The motor onset time was shorter in Group L than in Group R. The motor offset time was similar in the 2 groups, the time being slightly greater for Group R. Group L presented a higher difference of resolution to motor-sensitive block compared to Group R. CONCLUSIONS: The differences between Groups L and R were characterised by: a faster motor onset time in Group L with a longer time between motor and sensitive resolution determining a lower demand for analgesic drugs postoperatively and greater support for motor control recovery.

Amides↗

PubMed2003

Reduced sympathetic outflow and adrenal secretory activity during a 40-day stay in the Antarctic.

Human adaptation to unknown and extreme environments requires changes in the psychological and physical homeostasis. We previously reported a significant decrease of anterior pituitary and adrenal hormonal levels and a significant modification of psychophysiological correlates of stress, such as galvanic skin response, after exposure to Antarctica, suggesting a possible decrease of individual arousal. The latter was hypothesized to be correlated with a modification of autonomic balance, mainly represented by a possible reduction of adrenergic output. The aim of the present study was to assess the patterns of hormonal circadian rhythms and the autonomic nervous system balance by means of spectral analysis of heart rate variability (HRV). These parameters were evaluated during 3 sessions (baseline, session 1 and session 2), before, at the beginning and after a 40-day stay in Antarctica (Station of Terra Nova Bay; average temperature in the study period: -11 degrees C, 24 h of light, sea level). In each of the sessions, 6 healthy male subjects underwent a 24-h electrocardiogram and blood sampling (08.00, 12.00, 16.00, 20.00, 24.00 and 08.00 h) for hormonal determinations. The data showed a remarkable decrease of hormonal levels without significant changes in circadian rhythms. Spectral analysis of HRV showed an imbalance of the autonomic nervous system with a relative significant decrease of the low frequency band (0.1 Hz) in session 1 and 2 compared to baseline, which can be functionally interpreted as a relative decrement of the sympathetic component. In conclusion, the exposure to a cold and extreme environment seems to affect autonomic balance over a 40-day period. This is followed by a significant reduction of the anterior pituitary and adrenal hormonal secretory patterns with preserved hormonal circadian rhythms (within the same time period of 40 days). This pattern is suggestive of a trophotropic neurovegetative adaptive process.

Adrenal Glands↗

PubMed2003

Diamond detector versus silicon diode and ion chamber in photon beams of different energy and field size.

The aim of this work was to test the suitability of a PTW diamond detector for nonreference condition dosimetry in photon beams of different energy (6 and 25 MV) and field size (from 2.6 cm x 2.6 cm to 10 cm x 10 cm). Diamond behavior was compared to that of a Scanditronix p-type silicon diode and a Scanditronix RK ionization chamber. Measurements included output factors (OF). percentage depth doses (PDD) and dose profiles. OFs measured with diamond detector agreed within 1% with those measured with diode and RK chamber. Only at 25 MV, for the smallest field size, RK chamber underestimated OFs due to averaging effects in a pointed shaped beam profile. Agreement was found between PDDs measured with diamond detector and RK chamber for both 6 MV and 25 MV photons and down to 5 cm x 5 cm field size. For the 2.6 cm x 2.6 cm field size, at 25 MV, RK chamber underestimated doses at shallow depth and the difference progressively went to zero in the distal region. PDD curves measured with silicon diode and diamond detector agreed well for the 25 MV beam at all the field sizes. Conversely, the nontissue equivalence of silicon led, for the 6 MV beam, to a slight overestimation of the diode doses in the distal region, at all the field sizes. Penumbra and field width measurements gave values in agreement for all the detectors but with a systematic overestimate by RK measurements. The results obtained confirm that ion chamber is not a suitable detector when high spatial resolution is required. On the other hand, the small differences in the studied parameters, between diamond and silicon systems, do not lead to a significant advantage in the use of diamond detector for routine clinical dosimetry.

Diamond↗

PubMed2002

Characteristics of silicon and diamond detectors in a 60 MeV proton beam.

The calibration factor variation for a PTW natural diamond detector and a Scanditronix p-type stereotactic silicon diode (designed for use in photon beams) was studied in the 10-59 MeV range. Irradiations were performed in a water phantom with the 60 MeV ocular therapy beam at the CCO (UK). The diamond detector showed a sensitivity increase with energy, underestimating the dose by about 18% at the Bragg peak, by 7% at the centre and by 17% at the distal end of the SOBP region. The silicon diode did not show any significant sensitivity change with energy. However, a decrease in response of 24% was observed for an accumulated dose of 300 Gy.

Calibration↗

PubMed2002

Adrenaline plus cyanoacrylate injection for treatment of bleeding peptic ulcers after failure of conventional endoscopic haemostasis.

BACKGROUND: Endoscopic therapy is a safe and effective method for treating non-variceal upper gastrointestinal bleeding. However failure of therapy, in terms of continuing bleeding or rebleeding, is seen in up to 20%. Cyanoacrylate is a tissue glue used for variceal bleeding that has occasionally been reported as an alternative haemostatic technique in non-variceal haemorrhage. AIM: To retrospectively describe personal experience using cyanoacrylate injection in the management of bleeding ulcers after failure of first-line endoscopic modalities. PATIENTS AND METHODS: Between January 1995 and March 1998, 18 [12 M/6 F, mean age 68.1 years) out of 176 patients, referred to our Unit for non-variceal upper gastrointestinal bleeding, were treated with intralesional injection of adrenaline plus undiluted cyanoacrylate. Persistent bleeding after endoscopic haemostasis or early rebleeding were the indications for cyanoacrylate treatment. RESULTS: Definitive haemostasis was achieved in 17 out of 18 patients treated with cyanoacrylate. One patient needed surgery. No early or late rebleeding occurred during the follow-up. No complications or instrument lesions related to cyanoacrylate were recorded. CONCLUSIONS: In our retrospective series, cyanoacrylate plus adrenaline injection was found to be a potentially safe and effective alternative to endoscopic haemostasis when conventional treatment modalities fail in controlling bleeding from gastroduodenal ulcers.

Aged↗