Publications by authors named "Gabriele Chiara"

23 Publications

  • Page 1 of 1

Collision Models Can Efficiently Simulate Any Multipartite Markovian Quantum Dynamics.

Phys Rev Lett 2021 Apr;126(13):130403

Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC, UIB-CSIC), Campus Universitat de les Illes Balears, E-07122 Palma de Mallorca, Spain.

We introduce the multipartite collision model, defined in terms of elementary interactions between subsystems and ancillas, and show that it can simulate the Markovian dynamics of any multipartite open quantum system. We develop a method to estimate an analytical error bound for any repeated interactions model, and we use it to prove that the error of our scheme displays an optimal scaling. Finally, we provide a simple decomposition of the multipartite collision model into elementary quantum gates, and show that it is efficiently simulable on a quantum computer according to the dissipative quantum Church-Turing theorem, i.e., it requires a polynomial number of resources.
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http://dx.doi.org/10.1103/PhysRevLett.126.130403DOI Listing
April 2021

Quasistatic and quantum-adiabatic Otto engine for a two-dimensional material: The case of a graphene quantum dot.

Phys Rev E 2020 Jan;101(1-1):012116

Departamento de Física, Universidad Técnica Federico Santa María, 2390123 Valparaíso, Chile.

In this work, we study the performance of a quasistatic and quantum-adiabatic magnetic Otto cycles with a working substance composed of a single graphene quantum dot modeled by the continuum approach with the use of the zigzag boundary condition. Modulating an external or perpendicular magnetic field, in the quasistatic approach, we found a constant behavior in the total work extracted that is not present in the quantum-adiabatic formulation. We find that, in the quasistatic approach, the engine yielded a greater performance in terms of total work extracted and efficiency as compared with its quantum-adiabatic counterpart. In the quasistatic case, this is due to the working substance being in thermal equilibrium at each point of the cycle, maximizing the energy extracted in the adiabatic strokes.
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http://dx.doi.org/10.1103/PhysRevE.101.012116DOI Listing
January 2020

Three-qubit refrigerator with two-body interactions.

Phys Rev E 2020 Jan;101(1-1):012109

Centre for Theoretical Atomic, Molecular and Optical Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom.

We propose a three-qubit setup for the implementation of a variety of quantum thermal machines where all heat fluxes and work production can be controlled. An important configuration that can be designed is that of an absorption refrigerator, extracting heat from the coldest reservoir without the need of external work supply. Remarkably, we achieve this regime by using only two-body interactions instead of the widely employed three-body interactions. This configuration could be more easily realized in current experimental setups. We model the open-system dynamics with both a global and a local master equation thermodynamic-consistent approach. Finally, we show how this model can be employed as a heat valve, in which by varying the local field of one of the two qubits allows one to control and amplify the heat current between the other qubits.
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http://dx.doi.org/10.1103/PhysRevE.101.012109DOI Listing
January 2020

The growth of non-solid neoplastic lung nodules is associated with low PD L1 expression, irrespective of sampling technique.

J Transl Med 2020 02 3;18(1):54. Epub 2020 Feb 3.

Department of Medical Sciences and Infective Diseases, Unit of Respiratory Diseases, IRCCS Policlinico San Matteo Foundation and University of Pavia Medical School, 27100, Pavia, Italy.

Background: Few data are known regarding the molecular features and patterns of growth and presentation which characterize those lung neoplastic lesions presenting as non-solid nodules (NSN).

Methods: We retrospectively reviewed two different cohorts of NSNs detected by CT scan which, after transthoracic fine-needle aspiration (FNA) and core needle biopsy (CNB) received a final diagnosis of malignancy. All the enrolled patients were then addressed to surgical removal of lung cancer nodules or to exclusive radiotherapy. Exhaustive clinical and radiological features were available for each case.

Results: In all 62 analysed cases the diagnosis of adenocarcinoma (ADC) was reached. In cytologic samples, EGFR activating mutations were identified in 2 of the 28 cases (7%); no case showed ALK/EML4 or ROS1 translocations. In the histologic samples EGFR activating mutation were found in 4 out of 25 cases (16%). PD-L1 immunostains could be evaluated in 30 cytologic samples, while the remaining 7 did not reach the cellularity threshold for evaluation. TPS was < 1% in 26 cases,  > 1% < 50% in 3, and > 50% in 1. All surgical samples showed TPS < 1%. Of the 17 cases that could be evaluated on both samples, 15 were concordantly TPS 0, and 2 showed TPS > 1% < 50 on the biopsy samples. TPS was < 1% in 14 cases, > 1%/< 5% in 4 cases, > 5%/< 50% in 2 cases, > 50% in 1 case.

Conclusions: Overall PD-L1 immunostaining documented the predominance of low/negative TPS, with high concordance in FNA and corresponding surgical samples. It can be hypothesized that lung ADC with NSN pattern and predominant in situ (i.e. lepidic) components represent the first steps in tumor progression, which have not yet triggered immune response, and/or have not accumulated a significant rate of mutations and neoantigen production, or that they belong to the infiltrated-excluded category of tumors. The negative prediction of response to immunomodulating therapy underlines the importance of rapid surgical treatment of these lesions. Notably, cell block cytology seems to fail in detecting EGFR mutations, thus suggesting that this kind of sampling technique should be not adequate in case of DNA direct sequencing.
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http://dx.doi.org/10.1186/s12967-020-02241-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6998829PMC
February 2020

Thermodynamics of Weakly Coherent Collisional Models.

Phys Rev Lett 2019 Oct;123(14):140601

Instituto de Física da Universidade de São Paulo, 05314-970 São Paulo, Brazil.

We introduce the idea of weakly coherent collisional models, where the elements of an environment interacting with a system of interest are prepared in states that are approximately thermal but have an amount of coherence proportional to a short system-environment interaction time in a scenario akin to well-known collisional models. We show that, in the continuous-time limit, the model allows for a clear formulation of the first and second laws of thermodynamics, which are modified to include a nontrivial contribution related to quantum coherence. Remarkably, we derive a bound showing that the degree of such coherence in the state of the elements of the environment represents a resource, which can be consumed to convert heat into an ordered (unitarylike) energy term in the system, even though no work is performed in the global dynamics. Our results therefore represent an instance where thermodynamics can be extended beyond thermal systems, opening the way for combining classical and quantum resources.
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http://dx.doi.org/10.1103/PhysRevLett.123.140601DOI Listing
October 2019

A cloud-based computer-aided detection system improves identification of lung nodules on computed tomography scans of patients with extra-thoracic malignancies.

Eur Radiol 2019 Jan 15;29(1):144-152. Epub 2018 Jun 15.

Department of Radiology at Candiolo Cancer Institute-FPO, IRCCS, Strada Provinciale 142 km 3.95, 10060, Candiolo, Turin, Italy.

Objectives: To compare unassisted and CAD-assisted detection and time efficiency of radiologists in reporting lung nodules on CT scans taken from patients with extra-thoracic malignancies using a Cloud-based system.

Materials And Methods: Three radiologists searched for pulmonary nodules in patients with extra-thoracic malignancy who underwent CT (slice thickness/spacing 2 mm/1.7 mm) between September 2015 and March 2016. All nodules detected by unassisted reading were measured and coordinates were uploaded on a cloud-based system. CAD marks were then reviewed by the same readers using the cloud-based interface. To establish the reference standard all nodules ≥ 3 mm detected by at least one radiologist were validated by two additional experienced radiologists in consensus. Reader detection rate and reporting time with and without CAD were compared. The study was approved by the local ethics committee. All patients signed written informed consent.

Results: The series included 225 patients (age range 21-90 years, mean 62 years), including 75 patients having at least one nodule, for a total of 215 nodules. Stand-alone CAD sensitivity for lesions ≥ 3 mm was 85% (183/215, 95% CI: 82-91); mean false-positive rate per scan was 3.8. Sensitivity across readers in detecting lesions ≥ 3 mm was statistically higher using CAD: 65% (95% CI: 61-69) versus 88% (95% CI: 86-91, p<0.01). Reading time increased by 11% using CAD (296 s vs. 329 s; p<0.05).

Conclusion: In patients with extra-thoracic malignancies, CAD-assisted reading improves detection of ≥ 3-mm lung nodules on CT, slightly increasing reading time.

Key Points: • CAD-assisted reading improves the detection of lung nodules compared with unassisted reading on CT scans of patients with primary extra-thoracic tumour, slightly increasing reading time. • Cloud-based CAD systems may represent a cost-effective solution since CAD results can be reviewed while a separated cloud back-end is taking care of computations. • Early identification of lung nodules by CAD-assisted interpretation of CT scans in patients with extra-thoracic primary tumours is of paramount importance as it could anticipate surgery and extend patient life expectancy.
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http://dx.doi.org/10.1007/s00330-018-5528-6DOI Listing
January 2019

Genuine quantum correlations in quantum many-body systems: a review of recent progress.

Rep Prog Phys 2018 07 19;81(7):074002. Epub 2018 Apr 19.

Centre for Theoretical Atomic, Molecular and Optical Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom.

Quantum information theory has considerably helped in the understanding of quantum many-body systems. The role of quantum correlations and in particular, bipartite entanglement, has become crucial to characterise, classify and simulate quantum many body systems. Furthermore, the scaling of entanglement has inspired modifications to numerical techniques for the simulation of many-body systems leading to the, now established, area of tensor networks. However, the notions and methods brought by quantum information do not end with bipartite entanglement. There are other forms of correlations embedded in the ground, excited and thermal states of quantum many-body systems that also need to be explored and might be utilised as potential resources for quantum technologies. The aim of this work is to review the most recent developments regarding correlations in quantum many-body systems focussing on multipartite entanglement, quantum nonlocality, quantum discord, mutual information but also other non classical measures of correlations based on quantum coherence. Moreover, we also discuss applications of quantum metrology in quantum many-body systems.
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http://dx.doi.org/10.1088/1361-6633/aabf61DOI Listing
July 2018

Impact of a risk-based follow-up in patients affected by gastrointestinal stromal tumour.

Eur J Cancer 2017 06 24;78:122-132. Epub 2017 Apr 24.

Sarcoma Unit, Division of Medical Oncology Candiolo Cancer Institute - FPO, IRCCS, Strada Provinciale 142, Km 3.95, 10060 Candiolo, TO, Italy; University of Torino, Department of Oncology, Regione Gonzole, 10, 10043 Orbassano, TO, Italy. Electronic address:

Background: Follow-up aims to precociously identify recurrences, metastases or treatment-related adverse events so as to undertake the appropriate therapy. Guidelines admit lack of knowledge on optimal surveillance schedule, but suggest follow-up based on experts' opinion and risk stratification. To identify the impact, if any, of regular follow-up, we interrogated our prospectively collected database whether early detection of recurrences affected both clinical management and, likely, the outcome.

Patients And Methods: We required information to be available on primary surgery and ≥3°years of follow-up for non-recurring patients. We analysed recurrence characteristics (asymptomatic versus symptomatic, low- versus high tumour burden) and computed tomography (CT) scan counts to detect one recurrence. Kaplan-Meier method estimated recurrence-free survival (RFS), post-recurrence progression-free survival (PR-PFS), and disease-specific overall survival (OS). Comparisons used Hazard ratios (HR) with 95% confidence intervals (CIs). Multivariate analyses employed the Cox proportional hazards model. All tests were two-sided.

Results: Between 01/2001 and 12/2012 we found 233 study-eligible patients. Estimated 5- and 10-year RFS were 61.8% and 50.4%, respectively. After a 68-month median follow-up, we observed 94 (40.3%) recurrences [73/94 (77.7%) asymptomatic versus 21/94 (22.3%) symptomatic and 45/94 (47.9%) low- versus 49/94 (52.1%) high tumour burden]. Multivariate analysis revealed that symptomatic and high tumour burden recurrences were highly predictive of both worse PR-PFS (HR:3.19, P < 0.001; HR:2.80, P = 0.003, respectively) and OS (HR:3.65, P < 0.001; HR:2.38, P = 0.026, respectively). Finally, 29 second (primary) cancers were detected during follow-up.

Conclusions: Regular follow-up detects recurrences at an earlier stage and may be associated with a better PR-PFS and OS for these patients. In the absence of randomised trials, these evidences support follow-up effort and cost.
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http://dx.doi.org/10.1016/j.ejca.2017.03.025DOI Listing
June 2017

Work extraction and energy storage in the Dicke model.

Phys Rev E 2016 Nov 15;94(5-1):052122. Epub 2016 Nov 15.

Centre for Theoretical Atomic, Molecular and Optical Physics, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN, United Kingdom.

We study work extraction from the Dicke model achieved using simple unitary cyclic transformations keeping into account both a nonoptimal unitary protocol and the energetic cost of creating the initial state. By analyzing the role of entanglement, we find that highly entangled states can be inefficient for energy storage when considering the energetic cost of creating the state. Such a surprising result holds notwithstanding the fact that the criticality of the model at hand can sensibly improve the extraction of work. While showing the advantages of using a many-body system for work extraction, our results demonstrate that entanglement is not necessarily advantageous for energy storage purposes, when nonoptimal processes are considered. Our work shows the importance of better understanding the complex interconnections between nonequilibrium thermodynamics of quantum systems and correlations among their subparts.
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http://dx.doi.org/10.1103/PhysRevE.94.052122DOI Listing
November 2016

Equilibration and nonclassicality of a double-well potential.

Sci Rep 2016 Jan 29;6:19730. Epub 2016 Jan 29.

Centre for Theoretical Atomic, Molecular and Optical Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom.

A double well loaded with bosonic atoms represents an ideal candidate to simulate some of the most interesting aspects in the phenomenology of thermalisation and equilibration. Here we report an exhaustive analysis of the dynamics and steady state properties of such a system locally in contact with different temperature reservoirs. We show that thermalisation only occurs 'accidentally'. We further examine the nonclassical features and energy fluxes implied by the dynamics of the double-well system, thus exploring its finite-time thermodynamics in relation to the settlement of nonclassical correlations between the wells.
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http://dx.doi.org/10.1038/srep19730DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4809966PMC
January 2016

Shortcut to adiabaticity in the Lipkin-Meshkov-Glick model.

Phys Rev Lett 2015 May 1;114(17):177206. Epub 2015 May 1.

NEST, Scuola Normale Superiore and Istituto Nanoscienze CNR, I-56126 Pisa, Italy.

We study transitionless quantum driving in an infinite-range many-body system described by the Lipkin-Meshkov-Glick model. Despite the correlation length being always infinite the closing of the gap at the critical point makes the driving Hamiltonian of increasing complexity also in this case. To this aim we develop a hybrid strategy combining a shortcut to adiabaticity and optimal control that allows us to achieve remarkably good performance in suppressing the defect production across the phase transition.
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http://dx.doi.org/10.1103/PhysRevLett.114.177206DOI Listing
May 2015

Experimental reconstruction of work distribution and study of fluctuation relations in a closed quantum system.

Phys Rev Lett 2014 Oct 3;113(14):140601. Epub 2014 Oct 3.

Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, R. Santa Adélia 166, 09210-170 Santo André, São Paulo, Brazil.

We report the experimental reconstruction of the nonequilibrium work probability distribution in a closed quantum system, and the study of the corresponding quantum fluctuation relations. The experiment uses a liquid-state nuclear magnetic resonance platform that offers full control on the preparation and dynamics of the system. Our endeavors enable the characterization of the out-of-equilibrium dynamics of a quantum spin from a finite-time thermodynamics viewpoint.
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http://dx.doi.org/10.1103/PhysRevLett.113.140601DOI Listing
October 2014

Percutaneous vertebral augmentation assisted by PEEK implant in painful osteolytic vertebral metastasis involving the vertebral wall: experience on 40 patients.

Pain Physician 2013 Jul-Aug;16(4):E397-404

Institute for Cancer Research and Treatment, Turin, Italy.

Background: Vertebral metastases are associated with significant pain, disability, and morbidity. Open surgery for fracture stabilization is often inappropriate in this cancer population due to a poor risk-benefit profile, particularly if life expectancy is short. Vertebroplasty and kyphoplasty are appealing adjunctive procedures in patients with malignancy for alleviation of intractable pain. However, these patients have a higher risk of serious complications, notably cement extravasation.

Study Design: We prospectively evaluated clinical results of polyetheretherketone (PEEK) implant (Kiva) assisted vertebroplasty performed in malignant painful osteolytic lesions at risk for cement extravasation due to vertebral wall involvement.

Setting: Department of Interventional Radiology, Institute for Cancer Research and Treatment, Candiolo, Turin, Italy

Methods: Forty patients (22 women; mean age 66.8 ± 12.4), suffering from a painful spine malignancy with vertebral wall involvement not responding to conventional therapies and without surgical indications, underwent vertebral augmentation with Kiva intravertebral implant for pain palliation. The procedure was performed with moderate sedation and local anesthesia under combined digital fluoroscopy and computed tomography guidance. After the coil-shaped PEEK implant was deployed within the vertebral lesion, bone cement was injected under continuous digital fluoroscopic control. Patients were discharged from the hospital the next procedural day. The Visual Analog Scale (VAS) for pain, Oswestry Disability Index (ODI), analgesic requirement, and use of external brace support were evaluated to determine efficacy. The primary end-point was safety and efficacy at one month after the procedure. However, all the patients were scheduled to be followed-up at month 3, 6, and every 6 months thereafter. Follow-up was prospectively evaluated in all patients after Kiva with clinical interviews. The Institution's Internal Review Board approved this study.

Results: Median pre-treatment VAS of 10 (range 6 - 10) significantly (P < 0.001) dropped to one (range 0 - 3), with all patients achieving a clinically relevant benefit on pain at one month. Differences in pre- and post-treatment analgesic therapy were significant (P < 0.001). All patients no longer use an external brace after Kiva. In 7 out of 43 (16.3%) treated vertebrae a bone cement leakage was detected.

Limitations: This is a not randomized study. Participants were limited to 40 patients.

Conclusion: The Kiva System potentially represents a novel and effective minimally invasive treatment option for patients suffering from severe pain due to osteolytic vertebral metastases.
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March 2014

Vertebral augmentation with nitinol endoprosthesis: clinical experience in 40 patients with 1-year follow-up.

Cardiovasc Intervent Radiol 2014 Feb 8;37(1):193-202. Epub 2013 May 8.

Interventional Radiology Unit, Villa Maria Hospital, Strada Comunale di Mongreno 180, Turin, 10132, Italy,

Purpose: This study was designed to assess the clinical outcomes of patients treated by vertebral augmentation with nitinol endoprosthesis (VNE) to treat painful vertebral compression fractures.

Methods: Forty patients with one or more painful osteoporotic VCF, confirmed by MRI and accompanied by back-pain unresponsive to a minimum 2 months of conservative medical treatment, underwent VNE at 42 levels. Preoperative and postoperative pain measured with Visual Analog Scale (VAS), disability measured by Oswestry Disability Index (ODI), and vertebral height restoration (measured with 2-dimensional reconstruction CT) were compared at last follow-up (average follow-up 15 months). Cement extravasation, subsequent fractures, and implant migration were recorded.

Results: Long-term follow-up was obtained in 38 of 40 patients. Both VAS and ODI significantly improved from a median of 8.0 (range 5-10) and 66 % (range 44-88 %) to 0.5 (range 0-8) and 6 % (range 6-66 %), respectively, at 1 year (p < 0.0001). Vertebral height measurements comparing time points increased in a statistically significant manner (ANOVA, p < 0.001). Overall cement extravasation rate was 9.5 %. Discal and venous leakage rates were 7.1 and 0 % respectively. No symptomatic extravasations occurred. Five of 38 (13.1 %) patients experienced new spontaneous, osteoporotic fractures. No device change or migration was observed.

Conclusions: VNE is a safe and effective procedure that is able to provide long-lasting pain relief and durable vertebral height gain with a low rate of new fractures and cement leakages.
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http://dx.doi.org/10.1007/s00270-013-0623-1DOI Listing
February 2014

Vertebroplasty using transoral approach in painful malignant involvement of the second cervical vertebra (C2): a single-institution series of 25 patients.

Pain Physician 2012 Jan-Feb;15(1):35-42

Institute for Cancer Research and Treatment Candiolo, Turi, Italy.

Background: Vertebroplasty is a minimally invasive procedure demonstrated to be safe and effective in the treatment of painful osteoporotic and malignancy related fractures when performed in the thoracolumbar spine. Multiple randomized and nonrandomized reports have demonstrated its effectiveness. Conversely, transoral vertebroplasty (TOV) to treat the second cervical vertebra (C2) has been described in only a few case reports.

Objectives: Prospective evaluation of clinical results of TOV performed in malignant painful osteolytic lesions of C2.

Study Design: TOV was performed in 25 consecutive patients suffering from high-grade cervical pain due to malignant involvement of C2 who failed conservative therapies and did not have surgical indications. Follow-up was prospectively evaluated with clinical interviews in all patients. The Internal Review Board approved this study.

Setting: Institute for Cancer Research and Treatment

Methods: Twenty-five patients (16 women and 9 men; mean age 59.3 ± 11.5) suffering from a painful malignant involvement of C2 who did not respond to conventional therapies and did not have surgical indications, underwent TOV for pain palliation. The procedure was performed under general anesthesia with combined digital fluoroscopy and computed tomography guidance. After a beveled vertebroplasty needle was manually advanced up to the posterior odontoid wall, bone cement was injected under continuous digital fluoroscopic control. Patients were discharged from the hospital the next procedural day. The Visual Analog Scale (VAS) for pain, analgesic requirement, and use of external cervical cast support were used for evaluating efficacy. The main end point was safety and efficacy at day 15 after the procedure. Furthermore, all the patients were scheduled to be followed-up at months one, 3, and 6, and every 6 months thereafter.

Results: The median pretreatment VAS of 8 (range 5-10) significantly dropped (P < 0.0001) to 0 (range 0-10), with 20 patients (80%) achieving complete pain relief at day 15 after TOV. Differences in pre- and post-treatment analgesic therapy were significant (P < 0.001). Twenty-three patients no longer used a cervical cast after TOV (92%, P < 0.001). At median overall follow-up of 16 months (range 6-60 months), the projected proportion of patients free from worsening pain at 6, 12, and 24 months was 96%, 96% and 92% respectively.

Limitations: A randomized study of only 25 patients.

Conclusion: TOV is safe, effective, and long-lasting in the treatment of cervical pain resulting from malignant involvement of C2.
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August 2012

Percutaneous vertebroplasty in osteoporotic patients: an institutional experience of 1,634 patients with long-term follow-up.

J Vasc Interv Radiol 2011 Dec 22;22(12):1714-20. Epub 2011 Oct 22.

Institute for Cancer Research and Treatment , Candiolo, Turin, Italy.

Purpose: To assess long-term clinical outcome of percutaneous vertebroplasty (PV).

Materials And Methods: PV was performed in 1,634 patients (1,387 women; median age 73 years ± 9.3) with painful osteoporotic vertebral compression fractures (VCFs). All patients had back pain that persisted for ≥ 2 months with a concordant magnetic resonance imaging study. After PV, medical therapy for osteoporosis was continued, and patients were prospectively evaluated (follow-up 11.8-44.9 months, mean 25.0 months). Visual analog scale (VAS), Oswestry Disability Index (ODI), analgesic drug use, and use of external brace support were recorded at baseline and during follow-up. New occurrences of symptomatic vertebral fractures were recorded.

Results: The mean VAS score of 7.94 significantly improved to 1.12 at the primary endpoint (P < .001). Differences in patterns of analgesic usage compared with baseline values were highly statistically significant (marginal homogeneity test, P < .001). Median ODI values of 82% before treatment significantly decreased to 6% (P < .001). Before intervention, 1,279 patients wore a brace; 1,167 (91.2%) patients did not wear a brace after PV (χ(2) = 31.005, P < .0001). A new painful fracture with a significant higher proportion of contiguous vertebrae (63.6%) occurred in 214 (13.1%) patients (z = 7.59, P = .025).

Conclusions: PV can provide durable pain relief and improvement in ambulation in patients with VCFs.
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http://dx.doi.org/10.1016/j.jvir.2011.09.001DOI Listing
December 2011

Painful pathologic fracture of the humerus: percutaneous osteoplasty with bone marrow nails under hybrid computed tomography and fluoroscopic guidance.

J Vasc Interv Radiol 2011 Jul;22(7):1031-4

Interventional Radiology Unit, Institute for Cancer Research and Treatment, Strada Provinciale 135, Km 3.95, 10060 Candiolo, Turin, Italy.

A case of a 75-year-old patient with a painful pathologic humeral shaft fracture, with unacceptably high surgical risk and unsatisfactory analgesia is reported. In this case, impaired arm function and persistent pain with conservative management resulted in a poor quality of life. Palliation with image-guided percutaneous osteoplasty was considered. Because of potential cement leakage, inadequate fracture reduction, the site of the fracture, and the mobility of the joints in that area, image-guided percutaneous delivery of metallic bone marrow nails implanted together with polymethyl methacrylate (PMMA) osteoplasty was performed. This procedure achieved humeral shaft stabilization, bone fragment alignment, fracture reduction, and pain relief.
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http://dx.doi.org/10.1016/j.jvir.2011.02.021DOI Listing
July 2011

Percutaneous vertebroplasty in multiple myeloma: prospective long-term follow-up in 106 consecutive patients.

Cardiovasc Intervent Radiol 2012 Feb 9;35(1):139-45. Epub 2011 Feb 9.

Interventional Radiology Unit, Institute for Cancer Research and Treatment, 10060 Candiolo, Turin, Italy.

Purpose: Percutaneous vertebroplasty (PV) is a minimally invasive procedure involving the injection of bone cement within a collapsed vertebral body. Although this procedure was demonstrated to be effective in osteoporosis and metastases, few studies have been reported in cases of multiple myeloma (MM). We prospectively evaluated the safety and efficacy of PV in the treatment of vertebral compression fractures (VCFs) resulting from MM.

Materials And Methods: PV was performed in 106 consecutive MM patients who had back pain due to VCFs, the treatment of which had failed conservative therapies. Follow-up (28.2 ± 12.1 months) was evaluated at 7 and 15 days as well as at 1, 3, 6, 12, 18, and every 6 months after PV. Visual analog scale (VAS) pain score, opioid use, external brace support, and Oswestry Disability Index (ODI) score were recorded.

Results: The median pretreatment VAS score of 9 (range 4-10) significantly (P < 0.001) decreased to 1 (range 0-9) after PV. Median pre-ODI values of 82% (range 36-89%) significantly improved to 7% (range 0-82%) (P < 0.001). Differences in pretreatment and posttreatment use of analgesic drug were statistically significant (P < 0.001). The majority of patients (70 of 81; 86%) did not use an external brace after PV (P < 0.001).

Conclusion: PV is a safe, effective, and long-lasting procedure for the treatment of vertebral compression pain resulting from MM.
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http://dx.doi.org/10.1007/s00270-011-0111-4DOI Listing
February 2012

Role of CT colonography in inflammatory bowel disease.

Eur J Radiol 2009 Mar 22;69(3):404-8. Epub 2009 Jan 22.

Institute for Cancer Research and Treatment, Candiolo, Turin, Italy.

CT colonography (CTC), or virtual colonoscopy, is a non-invasive imaging method that uses CT data sets combined with specialized imaging software to examine the colon. CTC is not used routinely in patients with inflammatory bowel disease (IBD). However, investigating contemporarily the colon, other abdominal organs and the peritoneum with CTC is at times useful in patients with IBD, especially when other diagnostic tools fail. Furthermore, since symptoms of colorectal cancer sometimes superimpose to those of inflammatory disease, it may happen to image patients with IBD incidentally. If clinical signs are suggestive for inflammatory disease, exam technique should be modified accordingly and distinguishing radiological findings searched for.
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http://dx.doi.org/10.1016/j.ejrad.2008.11.027DOI Listing
March 2009

Phase diagram of spin-1 bosons on one-dimensional lattices.

Phys Rev Lett 2005 Dec 8;95(24):240404. Epub 2005 Dec 8.

NEST-INFM and Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy.

Spinor Bose condensates loaded in optical lattices have a rich phase diagram characterized by different magnetic order. Here we apply the density matrix renormalization group to accurately determine the phase diagram for spin-1 bosons loaded on a one-dimensional lattice. The Mott lobes present an even or odd asymmetry associated to the boson filling. We show that for odd fillings the insulating phase is always in a dimerized state. The results obtained in this work are also relevant for the determination of the ground state phase diagram of the S = 1 Heisenberg model with biquadratic interaction.
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http://dx.doi.org/10.1103/PhysRevLett.95.240404DOI Listing
December 2005

Berry phase for a spin 1/2 particle in a classical fluctuating field.

Phys Rev Lett 2003 Aug 28;91(9):090404. Epub 2003 Aug 28.

NEST-INFM & Scuola Normale Superiore, piazza dei Cavalieri 7, I-56126 Pisa, Italy.

The effect of fluctuations in the classical control parameters on the Berry phase of a spin 1/2 interacting with an adiabatically cyclically varying magnetic field is analyzed. It is explicitly shown that in the adiabatic limit dephasing is due to fluctuations of the dynamical phase.
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http://dx.doi.org/10.1103/PhysRevLett.91.090404DOI Listing
August 2003