Photonic quasi-crystal terahertz lasers.

Quasi-crystal structures do not present a full spatial periodicity but are nevertheless constructed starting from deterministic generation rules. When made of different dielectric materials, they often possess fascinating optical properties, which lie between those of periodic photonic crystals and those of a random arrangement of scatterers. Indeed, they can support extended band-like states with pseudogaps in the energy spectrum, but lacking translational invariance, they also intrinsically feature a pattern of 'defects', which can give rise to critically localized modes confined in space, similar to Anderson modes in random structures. If used as laser resonators, photonic quasi-crystals open up design possibilities that are simply not possible in a conventional periodic photonic crystal. In this letter, we exploit the concept of a 2D photonic quasi crystal in an electrically injected laser; specifically, we pattern the top surface of a terahertz quantum-cascade laser with a Penrose tiling of pentagonal rotational symmetry, reaching 0.1-0.2% wall-plug efficiencies and 65 mW peak output powers with characteristic surface-emitting conical beam profiles, result of the rich quasi-crystal Fourier spectrum.

Non-pegylated liposomal doxorubicin (Myocet®) in patients with poor-risk aggressive B-cell non-Hodgkin lymphoma.

The incidence of non-Hodgkin lymphomas increases with age. Non-pegylated liposomal formulations of doxorubicin (Myocet®) reduce systemic and cardiac toxicity especially in the elderly, who often have cardiac diseases. We treated 80 patients (mean age 70.9 years) with poor-risk diffuse large B-cell lymphoma with the R-COMP 21 regimen (Myocet® 50 mg/m(2), cyclophosphamide 750 mg/m(2), vincristine 1.4 mg/m(2), rituximab 375 mg/m(2), prednisone 100 mg/day). In all, 82.5% and 13.7% patients showed complete and partial responses, respectively. Sixty-two of the 80 patients are alive and disease-free (77.5%), while 3/80 are alive with active disease and 15 patients (18.7%) have died (median follow-up: 31 months). The estimated probability of overall survival at 12/24 months from admission was 93.5/87.3%, respectively. There were no therapy-related cardiac events and the ejection fraction improved (from 51.6 ±â€Š6.9% to 54.2 ±â€Š3.9%). Grade 3-4 neutropenia occurred in 22% of patients. We concluded that Myocet® shows both efficacy and tolerability, mainly at the cardiac level.

Photocurrent response from photonic crystal defect modes.

The authors use a quantum well intersubband photodetector fabricated into a two dimensional photonic crystal to investigate the optical defect modes of a single missing hole defect. The modes appear as a local enhancement in spectral photocurrent due to an increased in-coupling of surface incident light when a defect mode is present. The frequencies of these localized modes are tracked as they are varied by the defect geometry and compared to simulations.

Bortezomib (Velcade) for progressive myeloma after autologous stem cell transplantation and thalidomide.

Twenty-one patients with multiple myeloma, all relapsed after frontline autologous stem cell transplantation and all relapsed again after or resistant to thalidomide (employed as second line treatment) received bortezomib (1.3 mg/m(2) body surface twice weekly for 2 weeks followed by an interval of 10-12 days) without adjunct of steroids as third line therapy. Three patients died of progressive disease during the first 2 cycles with bortezomib. Eighteen patients received at least 2 cycles and were evaluated for response. According to EBMT criteria, two complete (negative immunofixation) and seven partial (reduction of M-component > 50-75%) remissions were achieved (ITT response rate 42.8%). Duration of response lasted from 2 to 14+ months. Grades 3-4 toxicities (thrombocytopenia, leucopenia, peripheral neuropathy and vasculitis) were observed in seven patients, but no patient interrupted the treatment due to side effects. We conclude that bortezomib alone may induce high quality responses as third line salvage therapy with acceptable toxicity in a significant proportion of homogeneously pre-treated myeloma patients with progressive disease after autologous transplantation and thalidomide.

Heterogeneity of response to imatinib-mesylate (glivec) in patients with hypereosinophilic syndrome: implications for dosing and pathogenesis.

Four cases of hypereosinophilic syndrome (HES) treated with the tyrosine-kinase inhibitor imatinib-mesylate are reported. The drug was effective in three patients, but a prolonged clinical and hematological remission was obtained only in one patient, due to appearance of resistance or poor tolerability in the other cases. The dose of imatinib necessary to achieve a response ranged from 100 to 600 mg/d. One patient with evidence of a clonal T-cell population did not respond at all. We confirm the efficacy of imatinib in HES, but we also underline that type and duration of response may be variable. This could be due to different pathogenetic mechanisms of the disease in single patients.

Pamidronate reduces skeletal events but does not improve progression-free survival in early-stage untreated myeloma: results of a randomized trial.

Ninety patients with untreated, stage I-II A myeloma, were randomised to receive or not monthly infusions of pamidronate (PMD) for 1 year, without additional therapies. Follow-up ranged from 36 to 72 months (median 51 months). Three years after the start of the treatment, the disease had progressed in 25% of PMD treated patients and in 26.8% of controls (p n.s). Median time-to-progression was 16 and 17.4 months, respectively (p n.s). Among the 21 patients who required chemo-radiotherapy, skeletal events (osteolytic lesions, pathological fractures and/or hypercalcemia) developed in 9/11 (81.8%) controls and in 4/10 (40%) of treated patients (p < 0.01). "Prophylactic" administration of PMD may decrease the development of skeletal events, but does not reduce the rate and the time of disease progression in early-stage myeloma.

Is the scoring system an effective clinico-biological tool in myeloid antigen positive adult acute lymphoblastic leukemia? Results of a long-term study.

INTRODUCTION: The classification and the clinical management of adult acute lymphoblastic leukemias (ALL) that co-express myeloid antigens (MyALL) remain controversial because of the confusion of terms and criteria to define these cases. MATERIALS AND METHODS: The characteristics of 112 adult ALL patients were reviewed. The scoring systems proposed by Catovsky and EGIL Group to classify MyALL were applied to qualify cases with score 0 (group I), 0.5-1.5 (group II) and 2 (group III). RESULTS: Forty-seven (42%) cases co-expressed MyAgs (group II: 29; group III: 18). A greater percentage of MyALL cases belonged to the earlier B and T subclasses. Ph+ incidence, WBC count and expression of CD34, CD45RA and CD25 were higher in group III. All patients received intensive therapy: out of these, 93 (83%) achieved CR. Although the response did not correlate significantly with the co-expression of MyAgs, the patients with the highest score had the lowest CR rate: 72, 83 and 86% in groups III, II and I, respectively. Surprisingly, the DFS curve of group III proved to be the most favorable. However, the OS was not significantly different, even if a worse curve was observed in group II. Multivariate analysis showed that only score 2 significantly affected DFS. CONCLUSION: The scoring system accurately defines diagnosis and ontogeny of MyALL which appear to be related to incidence of Ph chromosome, elevated WBC count and elderly age. Consequently, fewer CR rates were documented in MyALL with the highest score. However, it was in this group that the good responders showed a greater capacity to continue in first remission.