BACKGROUND: The optimal management of patients with recurrent CNS GCT, especially those with non-germinomatous (mixed malignant) GCT (MMGCT), remains unclear. Preliminary results are presented on the ...response rate, toxicity and early outcomes of a re-induction regimen of gemcitabine, oxaliplatin and paclitaxel (GEMPOX) administered, in responsive patients, prior to myeloablative chemotherapy and autologous hematopoietic cell rescue (HDCx + AuHCR). METHODS: Since December 2004, 13 recurrent or refractory patients (12 MMGCT, 1 germinoma; 12 males; mean age 16.5 years, range 7-34 years) have been treated with up to 4 cycles of gemcitabine (800 mg/m2), oxaliplatin (100 mg/m2) and paclitaxel (170 mg/m2), administered on one day at 14 days intervals. RESULTS: Of 13 patients, five were treated on a preceding feasibility pilot with 1-3 cycles of GEMPOX, and seven have been formally enrolled on an ongoing prospective multi-center trial. Six patients achieved complete remissions (tumor marker and/or imaging studies), five achieved partial remissions and two developed progressive disease (PD) while on GEMPOX; one patient with PD after 1 cycle had pathologically confirmed malignant transformation to pure embryonal rhabdomyosarcoma.; the second patient, with pure pineal choriocarcinoma, progressed following the second cycle of GEMPOX. Eleven of the 13 patents subsequently underwent HDCx + AuHCR. Six of them subsequently received irradiation. Transient hepatotoxicity and pancytopenia were the most commonly observed toxicities. Other toxicities included: paclitaxel anaphylaxis (1), transient encephalopathy (1), peripheral neuropathy (1), hyperesthesia (4), mucositis (2) and electrolyte imbalances (3). Four of the 12 patients with MMGCT continue alive and disease-free for 8+ , 10+ , 14+ and 16+ months since discontinuation of all therapy. One patient (with pure yolk sac tumor) relapsed in a loco-regional extra-CNS location (cavernous and ethmoid/sphenoid sinuses) and remains alive with progressive disease on therapy now 12+ months post-HDCx + AuHCR. CONCLUSIONS: GEMPOX appears to be an effective re-induction regimen for patients with recurrent CNS MMGCT, with acceptable toxicities. The ongoing multi-center, international trial should confirm this and demonstrate the contribution of GEMPOX towards improved survival when followed by HDCx + AuHCR with or without further irradiation, in the setting of minimal residual disease. SECONDARY CATEGORY: Pediatrics.
Repeatability problems, usually accompanied by low accuracy, are often experienced in power measurements, especially in those concerning spread spectrum signals, peculiar to digital wireless ...communication systems, and involving a specified frequency range. For this concern, a new method for power measurements is presented. The method applies original and straightforward digital signal-processing algorithms to the input signal power spectrum, preliminarily provided by optimized versions of well-known estimators, such as those based on weighted overlapped segment averaging and multitaper approaches. The outcomes of many experiments, conducted on spread spectrum signals of third-generation telecommunication systems, confirm the efficacy of the proposed method in assuring reliable and accurate results in various types of power measurement.
A method for measuring unknown thicknesses of multilayer structures, based on echo detection by means of the wavelet transform (WT), is presented. A brief discussion of the theoretical considerations ...underlying the method is first given. This highlights the excellent performance shown by the WT as a powerful tool for the analysis of echoes in a noisy environment. A suitable operating procedure for validation of the method is then set up. To this end, tests on 1) simulated signals and 2) actual signals received from known thicknesses are carried out: the obtained results are finally given and discussed.
A digital method for the measurement and characterization of Global System for Mobile Communications (GSM) equipment is presented here. The method, based on the use of time-frequency representations, ...shows itself suitable to carry out a whole range of measurements needed for compliance tests both for base stations and mobiles. It is so possible to avoid the employment of different instruments, complex procedures, and qualified users. Some aspects regarding GSM measurements are first presented to clearly describe the operative stages of the method. Then, its performance is assessed by analyzing reference signals. Experimental results obtained from the application of the method to actual GSM signals are finally given.
Measurement of phase and frequency errors, affecting the transmitted signal in digitally encoded cellular systems, is discussed here. To this aim, a new, cost-effective technique, particularly ...suitable in time domain multiple access (TDMA) systems, is proposed. In contrast to other measurement methods or instruments, the proposed technique gains burst synchronization on the analyzed signal through digital signal-processing, thus avoiding the need of sophisticated and expensive analog triggering solutions. Only a general-purpose data acquisition system is, in fact, required to capture a proper time window of the transmitted signal, preliminarily down-converted to intermediate frequency. Furthermore, in the same way as other methods or instruments, phase and frequency errors are evaluated according to a standard digital signal-processing procedure, which applies both for the actual and reference phase trajectory of the transmitted signal. The technique makes both trajectories available just at the end of the aforementioned burst synchronization stage, thus also optimizing the computational burden.
An intelligent FFT-analyzer Betta, G.; D'Apuzzo, M.; Liguori, C. ...
IEEE transactions on instrumentation and measurement,
10/1998, Volume:
47, Issue:
5
Journal Article
Peer reviewed
An intelligent FFT-analyzer capable of adapting its operating parameters on the basis of the signal spectrum was set up and characterized. The realized instrument is based on a parameter optimization ...procedure which provides the instrument an autoconfiguration capability. It was implemented on a multiple processor DSP architecture in order to achieve a real-time behavior. The experimental tests carried out on a large number of signals highlight the instrument capability of correctly detecting tones with a good frequency resolution for any signal spectrum type.
A knowledge-based instrument fault detection and isolation (IFDI) technique is proposed and described. It is based on the "duplication" of measurement devices by means of suitable mathematical ...relationships and is implemented on an expert system. The latter allows a mathematical model to be substituted by integrating qualitative models with empirical knowledge, thereby reducing overall computer effort without any corresponding decrease in diagnostic capabilities. This technique is particularly efficient when applied to detect and isolate faults in measurement systems integrated in control architectures. It is applied to an automatic measurement station for induction motor testing to illustrate its characteristics and performance. The experimental results are also reported, illustrating IFDI performance mainly in terms of promptness, sensitivity, and selectivity.< >
This paper deals with a method for the dynamic characterization of scan conversion-based transient digitizers. Such a method is based on the application to the digitized data of a two-dimensional ...filtering process, implemented by using the Walsh transform. The filtering process avoids incorrect evaluation of the digitizer dynamic performance. In order to test the proposed method, a scan converter model has been also developed. The validity and the application range of the method are illustrated through numerical and experimental results.< >
A method for the enhancement of dynamic performance of scan converter-based transient digitizers is proposed. First, a technique for discriminating the best diode target region is illustrated. Then, ...by considering the digitized charge distribution on the target as a digital image, a filtering algorithm capable of recovering trace discontinuities is shown. Results of tests carried out on an actual digitizer are reported.
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