20 research outputs found

    quantitative risk assessment of temporary hazards and maintenance worksites in the airport safety areas a case study

    Get PDF
    Abstract Airports are complex environments where the operational conditions are subjected to different risks, both due to the intrinsic nature of the manoeuvres themselves and to the external factors, as for human actions or environmental causes. An important risk factor is the presence of temporary hazards on the runway or taxiway safety area, including work in progress related to maintenance or construction operations. Both ICAO (International Civil Aviation Organization) and FAA (Federal Aviation Administration) defined their own approach on this topic. The FAA, in the Advisory Circular "Operational Safety on Airports During Construction", states the impossibility of any construction activities within the safety area when the runway is active, while the ICAO, in the Doc 9137 "Airport Service Manual" Part 6, states specific operational restrictions for the airport which allow the presence of temporary hazard in the safety area. This paper analyses the impact of temporary hazards (for example worksites) in the safety areas, according to ICAO requirements, by using a performance approach. The method has been applied to an international airport, using the software RSARA e LRSARA, provided by ACRP (The Airport Cooperative Research Program), in order to calculate the expected risk level within the safety area. This method provides a rapid and practical evaluation of risk level, according to the ICAO Safety Management System approach, in order to optimize the maintenance operation and construction in the safety area, minimizing the closing time of the runway. The main aim of this study is to verify if, under temporary restrictive operational condition (such as the limitation on available runway length and on traffic mix and weather conditions) related to the temporary hazard presence, it is possible to guarantee sufficient safety level, without occurring in runway closures. From the analysis arose that the first factor that affects the risk level for a runway is the temporary hazard dimension: while the environmental conditions (crosswind and pavement conditions) have a minor effect

    Stability of proICA512/IA-2 and its targeting to insulin secretory granules require β4-sheet-mediated dimerization of its ectodomain in the endoplasmic reticulum

    Get PDF
    The type 1 diabetes autoantigen ICA512/IA-2/RPTPN is a receptor protein tyrosine phosphatase of the insulin secretory granules (SGs) which regulates the size of granule stores, possibly via cleavage/signaling of its cytosolic tail. The role of its extracellular region remains unknown. Structural studies indicated that β2- or β4-strands in the mature ectodomain (ME ICA512) form dimers in vitro. Here we show that ME ICA512 prompts proICA512 dimerization in the endoplasmic reticulum. Perturbation of ME ICA512 β2-strand N-glycosylation upon S508A replacement allows for proICA512 dimerization, O-glycosylation, targeting to granules, and conversion, which are instead precluded upon G553D replacement in the ME ICA512 β4-strand. S508A/G553D and N506A/G553D double mutants dimerize but remain in the endoplasmic reticulum. Removal of the N-terminal fragment (ICA512-NTF) preceding ME ICA512 allows an ICA512-ΔNTF G553D mutant to exit the endoplasmic reticulum, and ICA512-ΔNTF is constitutively delivered to the cell surface. The signal for SG sorting is located within the NTF RESP18 homology domain (RESP18-HD), whereas soluble NTF is retained in the endoplasmic reticulum. Hence, we propose that the ME ICA512 β2-strand fosters proICA512 dimerization until NTF prevents N506 glycosylation. Removal of this constraint allows for proICA512 β4-strand-induced dimerization, exit from the endoplasmic reticulum, O-glycosylation, and RESP18-HD-mediated targeting to granules.Instituto Multidisciplinario de Biología Celula

    FISSIT (Fistula Surgery in Italy) study: A retrospective survey on the surgical management of anal fistulas in Italy over the last 15 years

    Get PDF
    Background: Surgical treatment of anal fistulas is still a challenge. The aims of this study were to evaluate the adoption and healing rates for the different surgical techniques used in Italy over the past 15 years. Methods: This was a multicenter retrospective observational study of patients affected by simple and complex anal fistulas of cryptoglandular origin who were surgically treated in the period 2003-2017. Surgical techniques were grouped as sphincter-cutting or sphincter-sparing and as technology-assisted or techno-free. All patients included in the study were followed for at least 12 months. Results: A total of 9,536 patients (5,520 simple; 4,016 complex fistulas) entered the study. For simple fistulas, fistulotomy was the most frequently used procedure, although its adoption significantly decreased over the years (P < .0005), with an increase in sphincter-sparing approaches; the overall healing rate in simple fistulas was 81.1%, with a significant difference between sphincter-cutting (91.9%) and sphincter-sparing (65.1%) techniques (P = .001). For complex fistulas, the adoption of sphincter-cutting approaches decreased, while sphincter-sparing techniques were mildly preferred (P < .0005). Moreover, there was a significant trend toward the use of technology-assisted procedures. The overall healing rate for complex fistulas was 69.0%, with a measurable difference between sphincter-cutting (81.1%) and sphincter-sparing (61.4%; P = .001) techniques and between techno-free and technology-assisted techniques (72.5% and 55.0%, respectively; P = .001). Conclusion: Surgical treatment of anal fistulas has changed, with a trend toward the use of sphincter-sparing techniques. The overall cure rate has remained stable, even if the most innovative procedures have achieved a lower success rate

    Stability of proICA512/IA-2 and its targeting to insulin secretory granules require β4-sheet-mediated dimerization of its ectodomain in the endoplasmic reticulum

    Get PDF
    The type 1 diabetes autoantigen ICA512/IA-2/RPTPN is a receptor protein tyrosine phosphatase of the insulin secretory granules (SGs) which regulates the size of granule stores, possibly via cleavage/signaling of its cytosolic tail. The role of its extracellular region remains unknown. Structural studies indicated that β2- or β4-strands in the mature ectodomain (ME ICA512) form dimers in vitro. Here we show that ME ICA512 prompts proICA512 dimerization in the endoplasmic reticulum. Perturbation of ME ICA512 β2-strand N-glycosylation upon S508A replacement allows for proICA512 dimerization, O-glycosylation, targeting to granules, and conversion, which are instead precluded upon G553D replacement in the ME ICA512 β4-strand. S508A/G553D and N506A/G553D double mutants dimerize but remain in the endoplasmic reticulum. Removal of the N-terminal fragment (ICA512-NTF) preceding ME ICA512 allows an ICA512-ΔNTF G553D mutant to exit the endoplasmic reticulum, and ICA512-ΔNTF is constitutively delivered to the cell surface. The signal for SG sorting is located within the NTF RESP18 homology domain (RESP18-HD), whereas soluble NTF is retained in the endoplasmic reticulum. Hence, we propose that the ME ICA512 β2-strand fosters proICA512 dimerization until NTF prevents N506 glycosylation. Removal of this constraint allows for proICA512 β4-strand-induced dimerization, exit from the endoplasmic reticulum, O-glycosylation, and RESP18-HD-mediated targeting to granules.Instituto Multidisciplinario de Biología Celula

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

    Get PDF
    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Assessment of intracochlear electrode position and correlation with behavioural thresholds in CII and 90K cochlear implants

    No full text
    Conclusion. The image quality of 64-MDCT provided excellent definition of the fine osseous structures and individual electrode contacts. Evaluation of electrode distances revealed a more focused stimulation for the Helix contacts, with better optimization of pulse width and frequency of stimulation. Objectives. A multi-slice CT scan was performed postoperatively to evaluate electrode distance from the modiolus and variability of fitting parameters ( M level) for two different types of cochlear implant electrode carriers, CII and 90K implants with 1J and Helix electrode carriers. Materials and methods. The electrode's position in different cochlear implant (CI) electrodes, Advanced Bionics 90K 1J and Helix, was assessed postoperatively in 20 adult patients by means of a 64-MDCT scanner. Axial, coronal, and oblique 0.3 mm multiplanar reconstructions ( MPRs) were obtained and datasets were analyzed to assess the intracochlear position and distance from the surface of the electrodes to the bony edge of the modiolus. Patients' fitting characteristics were gathered at the time the CT was performed and correlated to intracochlear measurements. Results. Determination of contact distances confirmed smaller average values for the Helix at the apex and medial segments. Helix electrodes were closer to the modiolus in all segments. Likewise, M level determination showed lower values for the Helix carrier, confirming a more focused stimulation and better optimization of pulse width and frequency of stimulation

    Minimally invasive approach to the adrenal gland in obese patients with Cushing’s syndrome

    No full text
    Introduction: The combination of Cushing’s syndrome and obesity, one of the most common manifestations of the syndrome itself, may be associated with the worsening of post-operative outcomes in case of laparoscopic adrenalectomy. This study focused on the laparoscopic treatment of Cushing’s syndrome with the purpose to identify any relevant difference between morbidly obese, mildly obese and non-obese patients. Material and methods: Patients were retrospectively divided into three groups according to their Body Mass Index (BMI). Demographic characteristics, operative and post-operative data were collected. Data about different hemostatic devices were also collected and compared. Differences were analyzed with the Fisher’s exact test for categorical variables, and the Mann-Whitney test for continuous variables. Results: No differences were found in operative time (101.5 ± 50.9 min; p =.919), conversion rate (2.6%; p =.655) or length of stay (4.3 ± 2.9 days; p =.886). Complication rate was 3% (p =.32), without any mortality. 95% of patients showed a complete resolution of hypercotisolyism-related symptoms, and a mean BMI reduction of 5 ± 3.2 kg/m2 (follow up = 6.3 ± 4.2 years). Conclusions: Laparoscopic adrenalectomy is safe and feasible in obese patients affected with Cushing’s disease and it can lead to the resolution of the related symptoms

    Follow-up of Cochlear Implant Use in Patients Who Developed Bacterial Meningitis Following Cochlear Implantation

    No full text
    Objectives/Hypothesis: The present study is a long-term follow-up of speech perception outcomes and cochlear implant use in three cases of meningitis that occurred after cochlear implantation. Study Design: Case series study. Methods: Study was performed on three children implanted with different models of Clarion (R) devices, two of them with positioner. Recognition and comprehension were assessed via the Italian adaptation of GASP (TAP) test, and phonetically balanced bi-syllabic words in open-set. High resolution computed tomography scan acquisition was performed to obtain axial coronal and oblique multiplanar reconstructions of the cochlea. Results: Two patients were affected by enlarged cochlear acqueduct and Mondini malformation the first carrying positioner. One patient had a normal cochlea, and the positioner could have been the main cause of bacterial spread. As a consequence of meningitis the child with normal-cochlea and the other with enlarged vestibular acqueduct developed cochlear ossification, increased M-level and worsening of hearing outcomes. The child with Mondini malformation developed facial nerve stimulation. Contralateral implantation was performed in the first two patients. Conclusion: Bacterial meningitis occuring after cochlear implantation may induce cochlear ossification, facial nerve stimulation, and permanent or temporary loss of implant use. Planned follow-up with high resolution computed tomography and evaluation of M-levels could be useful prognostic tools in the management of these patients
    corecore