Application of the THM to the investigation of reactions induced by unstable nuclei: the 18F(p,a)15O case

The Trojan Horse Method is applied to the investigation of the18F(p,a)15O reaction, by extractingthe quasi free contribution to the2H(18F,a15O)nprocess. For the first time the method is applied to a reaction ofastrophysical importance involving a radioactive nucleus. After investigating the reaction mechanism populat-ing thea+15O+nexit channel, we could extract the18F(p,a)15O cross section and calculate the astrophysicalfactor over the 0-1 MeV energy interval. The possibility of exploring the cross section with no need of ex-trapolation allowed us to to point out the possible occurrence of a 7/2+state at 126 keV, which would stronglyinfluence the trend of the astrophysical factor at the energies of astrophysical interest. However, the low energyresolution prevents us to draw definite conclusions. Possible astrophysical consequences are also discussed,motivating further work on this reaction.Peer ReviewedPostprint (published version

Biomarkers, imaging and disease activity indices in patients with early axial spondyloarthritis: The Italian arm of the SpondyloArthritis-Caught-Early (SPACE) Study

The study aimed to evaluate biomarkers facilitating early diagnosis of axial spondyloarthritis (axSpA) and correlations between them and disease activity parameters and imaging indexes. Patients with low back pain (LBP) ( 653 months, 642 years, onset 6445 years) participating in the Italian arm of the SpondyloArthritis-Caught-Early SPACE study underwent a physical examination, questionnaires, laboratory tests, X-rays and MRI of the spine and sacroiliac joints (SIJ). An expert rheumatologist formulated axSpA diagnosis in accordance with Assessment of SpondyloArthritis International Society (ASAS) criteria. Disease activity and physical functioning were assessed using imaging, clinical and serological indices. Spine and SIJ MRI and X-rays were scored independently by 2 readers using the SPARCC, mSASSS and NY-criteria. Patients were classified as: subjects with signs of radiographic sacroiliitis (r-axSpA), subjects with signs of sacroiliitis on SIJ-MRI but not on X-rays (nr-axSpA MRI SIJ+) or subjects with no signs of sacroiliitis on MRI/X-rays but with >2 SpA features and signs of bone oedema on MRI spine (nr-axSpA MRI SIJ-/undifferentiated SpA). Significant differences were found in the prevalence of radiographic sacroiliitis, active sacroiliitis on MRI and SPARCC SIJ scores. Biomarker levels were not significantly increased in any of the patient groups. The correlations between IL-17 and IL-23 and other indices were not significant; correlations were found between IL-22 and BASFI, BASG1, HAQ, VAS pain, between mSASSS and MMP3, and between the latter and hsCRP. Although not significantly higher in any of the three groups, IL-22, MMP3 and hsCRP values were correlated with some disease activity indexes and with mSASSS. Large observational studies are required to confirm these preliminary findings

Spine and sacroiliac joints on magnetic resonance imaging in patients with early axial spondyloarthritis: Prevalence of lesions and association with clinical and disease activity indices from the italian group of the SPACE study

Our aim was to determine the prevalence of spine and sacroiliac joint (SIJ) lesions on magnetic resonance imaging (MRI) in patients with early axial spondyloarthritis (axSpA) and their correlation with disease activity indices. Sixty patients with low back pain (LBP) (≥3 months, ≤2 years, onset ≤45 years), attending the SpA-clinic of the Unità Operativa Complessa Reumatologia of Padova [SpondyloArthritis-Caught-Early (SPACE) study], were studied following a protocol including physical examination, questionnaires, laboratory tests, X-rays and spine and SIJ MRI. Positive spine and SIJ MRI and X-rays images were scored independently by 2 readers using the SPARCC method, modified Stoke ankylosing spondylitis spine score and New York criteria. The axial pain and localization of MRI-lesions were referred to 4 sites: cervical/thoracic/lumbar spine and SIJ. All patients were classified into three groups: patients with signs of radiographic sacroiliitis (r-axSpA), patients without signs of r-axSpA but with signs of sacroiliitis on MRI (nr-axSpA MRI SIJ+), patients without signs of sacroiliitis on MRI and X-rays (nr-axSpA MRI SIJ-). The median age at LBP onset was 29.05±8.38 years; 51.6% of patients showed bone marrow edema (BME) in spine-MRI and 56.7% of patients in SIJ-MRI. Signs of enthesitis were found in 55% of patients in the thoracic district. Of the 55% of patients with BME on spine-MRI, 15% presented presented a negative SIJMRI. There was a significant difference between these cohorts with regard to the prevalence of radiographic sacroiliitis, active sacroiliitis on MRI and SPARCC SIJ score. The site of pain correlated statistically with BME lesions in thoracic and buttock districts. Since positive spine-MRI images were observed in absence of sacroiliitis, we can hypothesize that this finding could have a diagnostic significance in axSpA suspected axSpA

Diffusion-weighted magnetic resonance for assessing fibrosis in Crohn\u2019s disease

Background: Intestinal fibrosis is a key feature of Crohn\u2019s Disease lesions, and mucosal biopsies do not exactly represent transmural damage. Magnetic resonance enterography (MRE) allows for a panoramic study of the bowel loops. Diffusion-weighted imaging (DWI) through the restriction of the apparent diffusion coefficient (ADC) allows for an accurate evaluation of disease activity in Crohn\u2019s Disease patients avoiding contrast agents. The aim of this study was to investigate whether DWI sequences were able to identify intestinal fibrosis in candidates for surgery, using histopathology as the gold standard. Materials and methods: Thirty Crohn\u2019s Disease patients undergoing surgery for stricturing ileo-colonic disease were consecutively enrolled from October 2010 to November 2015. All patients underwent MRE with DWI before surgery. Radiological parameters were calculated in the stenotic segment and in the ileum proximal to the stenosis. The histopathological examination was performed using a histological score for fibrosis and inflammation. Results: ADC value correlated with the fibrosis score (r = 120.648; p 6.3 mm (AUC 0.89, specificity 100% and sensitivity 69.23%). The cut-off of ADC value for fibrosis was < 1.1 7 10 123 mm2 s 121 with a sensitivity of 72% and specificity of 94% (AUC = 0.83). Conclusions: The DWI sequence with ADC value could be useful to identify fibrosis in the intestinal wall of Crohn\u2019s Disease patients. \ua9 2019, Springer Science+Business Media, LLC, part of Springer Nature

The role of68ga-dota derivatives pet-ct in patients with ectopic acth syndrome

Introduction and aim: Ectopic ACTH secretion (EAS) is mostly secondary to thoracic/ abdominal neuroendocrine tumours (NETs) or small cell-lung carcinoma (SCLC). We studied the diagnostic accuracy of CT with68Ga-Dota derivatives (68Ga-SSTR) PET in localizing ACTH-secreting tumor in patients with EAS. Materials and methods:68Ga-SSTR-PET/CT was performed and compared with the nearest enhanced CT in 18 cases (16 primary and 2 recurrent neoplasms). Unspecific, indeterminate and false-positive uptakes were assessed using conventional imaging, follow-up or histology. Results: We diagnosed 13 thoracic (9 primary and 2 recurrent bronchial carcinoids, 2 SCLCs) and 1 abdominal (pancreatic NET) tumors. Eight ACTH-secreting tumors were promptly identified at EAS diagnosis (\u2019overt\u2019, four pulmonary carcinoids with two recurrences and two SCLC); six EAS have been discovered during the subsequent follow-up (\u2019covert\u2019, five bronchial carcinoids and one pancreatic NET). At the time of EAS diagnosis, imaging was able to correctly detect the ACTH-secreting tumour in 8/18 cases (6 new diagnosis and 2 recurrences). During the follow-up, six out of initially ten \u2018occult\u2019 cases became \u2018covert\u2019. At last available follow-up, CT and68Ga-SSTR-PET/CT were able to diagnose 11/18 and 12/18 ACTH-secreting tumours, respectively (11/14 and 12/14 considering only overt and covert cases, respectively). Four cases have never been localized by conventional or nuclear imaging (\u2019occult EAS\u2019), despite an average follow-up of 5 years. Conclusion: The68Ga-SSTR-PET/CT is useful in localizing EAS, especially to enhance positive prediction of the suggestive CT lesions and to detect occult neoplasms

Diffusion-weighted magnetic resonance for assessing ileal Crohn's disease activity.

Background: Endoscopy and imaging objectively assess Crohn\u2019s disease (CD) activity. Magnetic resonance enterography (MRE) uses no ionizing radiation, carries no significant morbidity, and is highly sensitive in revealing soft tissues inflammation. Diffusion-weighted imaging can distinguish intestinal inflammation from a lower diffusion of water molecules giving rise to a reduced apparent diffusion coefficient. The magnetic resonance index of activity score and, more recently, the Clermont score were recently developed for staging CD activity. The aim of this study was to compare the MRE scores and the Simple Endoscopic Score for CD in identifying ileal CD activity. Methods: Fifty-five patients with ileal and ileocolonic CD were consecutively enrolled between June 2012 and June 2013. All patients underwent clinical examination, biochemical tests, MRE, and colonoscopy to assess disease activity. Results: MRE assessed active ileal disease in 31 patients (56.3%). The Clermont score significantly correlated with the magnetic resonance index of activity score (r \ubc 0.91; P , 0.0001) and the Simple Endoscopic Score for CD (r \ubc 0.76; P , 0.0001). The apparent diffusion coefficient correlated with the Simple Endoscopic Score for CD (r \ubc 20.63; P , 0.0001) especially in unoperated patients. Conclusions: The Clermont score and the apparent diffusion coefficient value can stage ileal CD, avoiding the need to use contrast agents