In this work, a novel baseline-free procedure aimed at detecting and sizing delaminations in composite plates is proposed. To such a purpose an air-coupled probe is used to measure the sound pressure ...in air that is generated by leaky guided waves traveling along the plate and scattered by defects. In particular, by scanning the plate surface with a proper probe tilt angle and lift-off, wavefields dominated by a single guided mode can be obtained. Then, a processing procedure based on warped time–frequency operators is used to filter out the main wavefield generated by the acoustic source in order to enhance the one scattered by defects. Such operators are designed basing on the dispersion curves of the dominant guided mode considered. Finally, it is shown how the scattered wavefield can be further processed to infer the defect position and size by means of the Circular Hough Transform.
The presence of a barely visible delamination on a 4.9mm thick composite laminate was detected by exploiting the proposed approach. The obtained results are in good agreement with those obtained by using a commercial phased-array ultrasonic C-scan device.
The combination of serum β2-microglobulin and albumin levels has been shown to be highly prognostic in myeloma as the International Staging System (ISS). The aim of this study was to assess the ...independent contributions of ISS stage and cytogenetic abnormalities in predicting outcomes. A retrospective analysis of international studies looking at both ISS and cytogenetic abnormalities was performed in order to assess the potential role of combining ISS stage and cytogenetics to predict survival. This international effort used the International Myeloma Working Group database of 12 137 patients treated worldwide for myeloma at diagnosis, of whom 2309 had cytogenetic studies and 5387 had analyses by fluorescent in situ hybridization (iFISH). Comprehensive analyses used 2642 patients with sufficient iFISH data available. Using the comprehensive iFISH data, combining both t(4;14) and deletion (17p), along with ISS stage, significantly improved the prognostic assessment in terms of progression-free survival and overall survival. The additional impact of patient age and use of high-dose therapy was also demonstrated. In conclusion, the combination of iFISH data with ISS staging significantly improves risk assessment in myeloma.
Aberrations on TP53, either as deletions of chromosome 17p (del17p) or mutations, are associated with poor outcome in multiple myeloma (MM), but conventional detection methods currently in use ...underestimate their incidence, hindering an optimal risk assessment and prognostication of MM patients. We have investigated the altered status of TP53 gene by SNPs array and sequencing techniques in a homogenous cohort of 143 newly diagnosed MM patients, evaluated both at diagnosis and at first relapse: single-hit on TP53 gene, either deletion or mutation, detected both at clonal and sub-clonal level, had a minor effect on outcomes. Conversely, the coexistence of both TP53 deletion and mutation, which defined the so-called double-hit patients, was associated with the worst clinical outcome (PFS: HR 3.34 95% CI: 1.37-8.12 p = 0.008; OS: HR 3.47 95% CI: 1.18-10.24 p = 0.02). Moreover, the analysis of longitudinal samples pointed out that TP53 allelic status might increase during the disease course. Notably, the acquisition of TP53 alterations at relapse dramatically worsened the clinical course of patients. Overall, our analyses showed these techniques to be highly sensitive to identify TP53 aberrations at sub-clonal level, emphasizing the poor prognosis associated with double-hit MM patients.
For almost 10 years imatinib has been the therapeutic standard of chronic myeloid leukemia. The introduction of other tyrosine kinase inhibitors (TKIs) raised a debate on treatment optimization. The ...debate is still heated: some studies have protocol restrictions or limited follow-up; in other studies, some relevant data are missing. The aim of this report is to provide a comprehensive, long-term, intention-to-treat, analysis of 559 newly diagnosed, chronic-phase, patients treated frontline with imatinib. With a minimum follow-up of 66 months, 65% of patients were still on imatinib, 19% were on alternative treatment, 12% died and 4% were lost to follow-up. The prognostic value of BCR-ABL1 ratio at 3 months (⩽10% in 81% of patients) was confirmed. The prognostic value of complete cytogenetic response and major molecular response at 1 year was confirmed. The 6-year overall survival was 89%, but as 50% of deaths occurred in remission, the 6-year cumulative incidence of leukemia-related death was 5%. The long-term outcome of first-line imatinib was excellent, also because of second-line treatment with other TKIs, but all responses and outcomes were inferior in high-risk patients, suggesting that to optimize treatment results, a specific risk-adapted treatment is needed for such patients.
We investigated the influence of molecular status on disease characteristics and clinical outcome in young patients (⩽ 40 years) with World Health Organization (WHO)-defined essential thrombocythemia ...(ET) or early/prefibrotic primary myelofibrosis (early-PMF). Overall, 217 patients with ET (number 197) and early-PMF (number 20) were included in the analysis. Median follow-up time was 10.2 years. The cumulative incidence of thrombosis, hemorrhages and disease evolution into myelofibrosis/acute leukemia were 16.6%, 8.6% and 3% at 15 years, respectively. No differences were detectable between ET and early-PMF patients, although the latter cohort showed a trend for worse combined-event free survival (EFS). Mutation frequency were 61% for JAK2V617F, 25% for CALR and 1% for MPLW515K, and were comparable across WHO diagnosis; however, JAK2V617F allele burden was higher in the early-PMF group. Compared with JAK2V617F-positive patients, CALR-mutated patients displayed higher platelet count and lower hemoglobin level. CALR mutations significantly correlated with lower thrombotic risk (9.1% versus 21.7%, P = 0.04), longer survival (100% versus 96%, P = 0.05) and better combined-EFS (86% versus 71%, P = 0.02). However, non-type 1/type 2 CALR mutations ('minor' mutations) and abnormal karyotype were found to correlate with increased risk of disease evolution. At last contact, six patients had died; in five cases, the causes of death were related to the hematological disease and occurred at a median age of 64 years (range: 53-68 years). Twenty-eight patients (13%) were unmutated for JAK2, CALR and MPL: no event was registered in these 'triple-negative' patients.
The serine/threonine kinase Akt, a downstream effector of phosphatidylinositol 3-kinase (PI3K), is known to play an important role in antiapoptotic signaling and has been implicated in the ...aggressiveness of a number of different human cancers including acute myelogenous leukemia (AML). We have investigated the therapeutic potential of the novel Akt inhibitor, perifosine, on human AML cells. Perifosine is a synthetic alkylphospholipid, a new class of antitumor agents, which target plasma membrane and inhibit signal transduction networks. Perifosine was tested on THP-1 and MV 4-11 cell lines, as well as primary leukemia cells. Perifosine treatment induced cell death by apoptosis in AML cell lines. Perifosine caused Akt and ERK 1/2 dephosphorylation as well as caspase activation. In THP-1 cells, the proapoptotic effect of perifosine was partly dependent on the Fas/FasL system and c-jun-N-kinase activation. In MV 4-11 cells, perifosine downregulated phosphorylated Akt, but not phosphorylated FLT3. Moreover, perifosine reduced the clonogenic activity of AML, but not normal, CD34(+) cells, and markedly increased blast cell sensitivity to etoposide. Our findings indicate that perifosine, either alone or in combination with existing drugs, might be a promising therapeutic agent for the treatment of those AML cases characterized by upregulation of the PI3K-Akt survival pathway.
Hyperactivation of the Hedgehog (Hh) pathway, which controls refueling of multiple myeloma (MM) clones, might be critical to disease recurrence. Although several studies suggest the Hh pathway is ...activated in CD138- immature cells, differentiated CD138+ plasma cells might also be able to self-renew by producing themselves the Hh ligands. We studied the gene expression profiles of 126 newly diagnosed MM patients analyzed in both the CD138+ plasma cell fraction and CD138-CD19+ B-cell compartment. Results demonstrated that an Hh-gene signature was able to cluster patients in two subgroups characterized by the opposite Hh pathway expression in mature plasma cells and their precursors. Strikingly, patients characterized by Hh hyperactivation in plasma cells, but not in their B cells, displayed high genomic instability and an unfavorable outcome in terms of shorter progression-free survival (hazard ratio: 1.92; 95% confidence interval: 1.19-3.07) and overall survival (hazard ratio: 2.61; 95% confidence interval: 1.26-5.38). These results suggest that the mechanisms triggered by the Hh pathway ultimately led to identify a more indolent vs a more aggressive biological and clinical subtype of MM. Therefore, patient stratification according to their molecular background might help the fine-tuning of future clinical and therapeutic studies.
The emergence of resistance to the Bcr-Abl inhibitor imatinib mesylate in patients with Philadelphia chromosome-positive (Ph+) leukemia has prompted the development of second-generation compounds ...active against several imatinib-insensitive mutant forms of Bcr-Abl, including dasatinib (BMS-354825; Bristol-Myers Squibb). In order to assess which pre-existent or emerging kinase domain mutations are associated with decreased clinical efficacy of desatinib, we analyzed BCR-ABL kinase sequences before and during treatment in 21 Ph+ patients who failed to respond to or relapsed during dasatinib therapy. In all patients but one, resistance to dasatinib was invariably found to be associated with mutations at residue 315 and/or at residue 317.
The marked synergy of thalidomide and dexamethasone in advanced and refractory multiple myeloma (MM) provided the basis for a phase 2 clinical study aimed at investigating the efficacy and toxicity ...of this combination as first-line therapy for patients less than 65 years old with newly diagnosed disease.
Both thalidomide and dexamethasone were administered for 4 months in an attempt to reduce tumor cell mass before collection of peripheral blood stem cells (PBSC) and subsequent double autologous transplantation. Thalidomide was given at the fixed dose of 200 mg/day; dexamethasone was administered at the dose of 40 mg/day on days 1-4, 9-12 and 17- 20 in odd cycles and 40 mg/day on days 1-4 in even cycles, repeated monthly.
Seventy-one patients with symptomatic MM were evaluated for response and toxicity. On an intent-to-treat basis, the overall response (>or= partial remission) rate was 66%, including 17% of patients who attained a complete remission or a very good partial remission. In addition to common toxicity of thalidomide, deep-vein thrombosis was a troublesome adverse event (16%). Nine patients (13%) required thalidomide discontinuation because of toxicity, including 3 patients who died during the study treatment. Fifty-nine patients proceeded to PBSC mobilization and yielded a median number of 7.1x10(6) CD 34(+ ) cells/kg.
The combination of thalidomide and dexamethasone is an effective and relatively well tolerated induction regimen for previously untreated patients with MM. This combination may provide an oral alternative to vincristine-doxorubicin-dexamethasone in preparation for autologous stem cell transplantation.
The aim of this study was to investigate the effects of a non-standard, intermittent imatinib treatment in elderly patients with Philadelphia-positive chronic myeloid leukaemia and to answer the ...question on which dose should be used once a stable optimal response has been achieved. Seventy-six patients aged ⩾65 years in optimal and stable response with ⩾2 years of standard imatinib treatment were enrolled in a study testing a regimen of intermittent imatinib (INTERIM; 1-month on and 1-month off). With a minimum follow-up of 6 years, 16/76 patients (21%) have lost complete cytogenetic response (CCyR) and major molecular response (MMR), and 16 patients (21%) have lost MMR only. All these patients were given imatinib again, the same dose, on the standard schedule and achieved again CCyR and MMR or an even deeper molecular response. The probability of remaining on INTERIM at 6 years was 48% (95% confidence interval 35-59%). Nine patients died in remission. No progressions were recorded. Side effects of continuous treatment were reduced by 50%. In optimal and stable responders, a policy of intermittent imatinib treatment is feasible, is successful in about 50% of patients and is safe, as all the patients who relapsed could be brought back to optimal response.
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