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Heat shock proteins (HSPs) attract the attention of scientists and clinicians due to their potential role as diagnostic and prognostic factors in a variety of cancers. HSP90 is one of the most important and well-known family members, necessary for maintaining intracellular homeostasis. In the extracellular space, it is responsible for the transmission of alarm signals to the immune system. Numerous reports have indicated that the level of intra - and extracellular HSP90 can correlate either with a poorer prognosis or with a better outcome, depending on the type of cancer. Still, little is known why the level of this chaperone is increased in some tumors and decreased in others, reflecting dual role of protein in cell death processes. Currently, there is no database reporting levels of serum HSP90 in children with acute lymphoblastic leukemia (ALL). As such, using enzyme-linked immunosorbent assay (ELISA) method, we aimed to determine this parameter in a group of 21 patients with newly diagnosed ALL. We found decreased protein serum levels in patients at disease presentation and after induction block of chemotherapy in comparison to healthy controls. Furthermore, we observed a negative correlation between HSP90 serum levels and one of the earliest prognostic factors of the treatment response - peripheral blood lymphoblasts on the 8th day of treatment. Our results indicate that HSP90 serum may play an important role in leukemogenesis and could be used as a marker to predict treatment failure in children with ALL.

Accurate identification of stochastic systems with fast-varying parameters is a challenging task which cannot be accomplished using model-free estimation methods, such as weighted least squares, which assume only that system coefficients can be regarded as locally constant. The current state-of-the-art solutions are based on the assumption that system parameters can be locally approximated by a linear combination of appropriately chosen basis functions. The paper shows that tracking performance of the resulting local basis function estimation algorithms can be further improved by means of regularization. The method is illustrated by an important recent application - identification of fast time-varying acoustic channels used in underwater communication.

Two recursive least-square (RLS) adaptive filtering algorithms are most often used in practice, the exponential and sliding (rectangular) window RLS algorithms. This popularity is mainly due to existence of low-complexity versions of these algorithms. However, these two windows are not always the best choice for identification of fast time-varying systems, when the identification performance is most important. In this paper, we show how RLS algorithms with arbitrary finite-length windows can be implemented at a complexity comparable to that of the exponential and sliding window RLS algorithms. Then, as an example, we show an improvement in the performance when using the proposed finite-window RLS algorithm with the Hanning window for identification of fast time-varying systems.p, li { white-space: pre-wrap; }

Flow cytometry (FCM) is a precise and well-established tool to assess the minimal residual disease (MRD) level in childhood acute lymphoblastic leukemia (ALL). It is crucial to distinguish leukemic cells from their normal counterparts; thus new markers should be evaluated, to increase the accuracy of the analysis. The expression of CD73 on blast cells was measured and compared at the day of diagnosis and at days 15 and 33 of treatment. To determine antigen expression levels, a normalized scale based on median fluorescence intensity (nMFI) was used. The study group consisted of 188 patients from the Polish Pediatric Leukemia and Lymphoma Study Group. From 177 patients with positive MRD at day 15 of treatment, in 147 (83.1%) cases an increase of CD73 expression was observed (mean increase of +17 nMFI units). In addition, an increase of CD73 expression was noted in 26 of 31 (83.9%) patients at day 33 of treatment. In turn, a decrease of CD73 expression was observed only in 13/177 (7.3%) and 1/31 (3.2%) cases at days 15 and 33 of treatment, respectively. In 17 (9.6%) patients no change in expression of CD73 between diagnosis and day 15 of treatment was observed. In the great majority of cases the expression of CD73 is not only stable but increases during the early stages of treatment, which makes it a very useful marker to be used for MRD monitoring in childhood B-cell precursor (BCP)-ALL patients.

HSPs demonstrate a strong association with gamma-delta (γδ) T cells. Most of the studies regarding interactions between the parameters were conducted in the 1990s. Despite promising results, the concept of targeting γδ T cells by HSPs seems to be a forgotten direction due to potent non-peptidic phosphoantigens rather than HSPs have been found to be the essential stimulatory components for human γδ cells. Currently, with greater knowledge of lymphocyte diversity, and more accurate diagnostic methods, we decided to study the correlation once again in the neoplastic condition. Twenty-one children with newly diagnosed acute lymphoblastic leukaemia (ALL) were enrolled on the study. Serum HSP90 concentrations were evaluated by an enzyme-linked immunosorbent assay (ELISA), subsets of γδ T cells (CD3+ γδ, CD3+ γδ HLA/DR+, CD4+ γδ and CD8+ γδ) by flow cytometry. We have shown statistically relevant correlations between serum HSP90 and CD3+ HLA/DR+ γδ T cells in paediatric ALL at diagnosis (R = 0.53, p &lt, 0.05), but not after induction chemotherapy. We also have demonstrated decreased levels of both serum HSP90 and CD3+ HLA/DR+ γδ T cells before treatment, which may indirectly indicate dose-dependent unknown interaction between the parameters. The results of our study may be a good introduction to research on the association between HSPs and CD3+ HLA/DR+ γδ T cells, which could be an interesting direction for the development of anti-cancer strategies, not just for childhood ALL.

Background/aim The risk factors, clinical features and non-hematological toxicity profiles during chemotherapy in acute lymphoblastic leukemia (ALL) patients treated in pediatric hematology centres were analysed. Materials and methods A total of 902/1872 children were reported as having grade 3 or 4 toxicity. Results Among the analysed toxicities, infection and gastrointestinal and liver toxicities were the most common. The median follow-up was 6.8 years. Overall survival and event-free survival rates for the analysed group were lower than those reported for the group without grade ≥3 toxicity. In univariate analysis, we identified the number of toxic episodes, the risk group and remission status that had a significant impact on the outcome. Multivariate analysis demonstrated the risk group and the number of toxic episodes ≥3 to be statistically significant for the results. Conclusion The toxic profiles investigated in our report should be used in future efforts to decrease the burden of side effects during chemotherapy.

In this chapter, a new approach to active narrowband noise control is presented. Narrowband acoustic noise may be generated, among others, by rotating parts of electro-mechanical devices, such as motors, turbines, compressors, or fans. Active noise control involves the generation of “antinoise”, i.e., the generation of a sound that has the same amplitude, but the opposite phase, as the unwanted noise, which causes them to interfere destructively, rather than constructively. In the range of low frequencies (below 1 kHz), the active approach is more effective than passive methods that employ dampers, barriers, absorbers, and other forms of acoustic isolation.

Acute lymphoblastic leukemia (ALL) is the leading cause of cancer related death in children despite recent advances showing improved responses to chemotherapy treatment. Gamma-delta (γδ) T cells are a recent topic of growing interest in the field of adoptive immunotherapy. These cells have also been proven to be an optimal predictor of a favorable outcome in numerous malignancies. We evaluated subgroups of γδ T cells in the peripheral blood of 19 children with newly diagnosed ALL at the time of diagnosis and following chemotherapy induction. Due to the fact that serum HSP90 serves as a ligand for γδ T cells, we also checked the correlation between HSP90 and γδ T cells. As a result, we found, that the number of CD8+ γδ T cells in peripheral blood at disease presentation was almost three times higher in the intermediate risk group compared to patients in high risk group. Furthermore, we observed higher percentages of the subset in younger patients at diagnosis and after induction, but not in healthy controls. We also noticed negative correlations between CD8+ γδ T cells and minimal residual disease (MRD) before chemotherapy and after induction. We showed a positive association between activated CD3+ γδ T cell and serum HSP90 at presentation. In conclusion, our data suggests that CD8+ γδ T cells may be an early marker of favorable prognosis in childhood ALL while serum HSP90 may act as an agent activating CD3+ γδ T effector cells.

The aim of the study was to retrospectively compare the effectiveness of the ALL IC-BFM 2002 and ALL IC-BFM 2009 protocols and the distribution of risk groups by the two protocols after minimal residual disease (MRD) measurement as well as its impact on survival. We reviewed the medical records of 3248 patients aged 1–18 years with newly diagnosed ALL who were treated in 14 hemato-oncological centers between 2002 and 2018 in Poland. The overall survival (OS) of 1872 children with ALL treated with the ALL IC 2002 protocol was 84% after 3 years, whereas the OS of 1376 children with ALL treated with the ALL IC 2009 protocol was 87% (P P = 0.006). Our study shows that the ALL IC-BFM 2009 protocol improved the results of children with ALL compared to the ALL IC-BFM 2002 protocol in Poland. This analysis confirms that MRD marrow assessment on day 15 of treatment by FCM-MRD is an important predictive factor.

Objective The aim of this study was to analyse the clinical characteristics and outcome of children diagnosed with Ph+ ALL. Material and methods A total of 2591 newly diagnosed ALL children were treated in Poland between the years 2005 and 2017. Of those, 44 were diagnosed with Ph(+) ALL. The patients were treated according to protocols: ALL IC-BFM 2002 and 2009 (26 patients), EsPhALL (12 patients), initially ALL IC-BFM and then EsPhALL (6 patients). Results The median of follow-up in the observed group was 3 years. Overall survival (OS) and event-free survival (EFS) of Ph+ ALL group were 0.73 and 0.64. OS and EFS of patients after HSCT were 0.78 and 0.66, while without HSCT were 0.6 and 0.6, P = 0.27 and 0.63. OS was 0.8 for patients treated with chemotherapy plus imatinib and 0.61 for chemotherapy alone, P = 0.22, while EFS was 0.66 (imatinib therapy) and 0. 61 (without imatinib), P = 0.41. Conclusion Our study suggests that adding imatinib to intensive chemotherapy seems to improve outcome. However, this study was limited by a small number of patients and a variety of chemotherapy regimens with or without imatinib.

The problem of identification of multivariate autoregressive processes (systems or signals) with unknown and possibly time-varying model order and time-varying rate of parameter variation is considered and solved using parallel estimation approach. Under this approach, several local estimation algorithms, with different order and bandwidth settings, are run simultaneously and compared based on their predictive performance. First, the competitive decision schemes are considered. It is shown that the best parameter tracking results can be obtained when the order is selected based on minimization of the appropriately modified Akaike's final prediction error statistic, and the bandwidth is chosen using the localized version of the Rissanen's predictive least squares statistic. Next, it is shown that estimation results can be further improved if a collaborative decision is made by means of applying the Bayesian model averaging technique.

The problem of identification of a nonstationary autoregressive signal using non-causal estimation schemes is considered. Noncausal estimators can be used in applications that are not time-critical, i.e., do not require real-time processing. A new adaptive estimation bandwidth selection rule based on evaluation of pseudoprediction errors is proposed, allowing one to adjust tracking characteristics of noncausal estimators to unknown and/or time-varying degree of signal nonstationary. The new rule is compared with the previously proposed one, based on the generalized Akaike’s final prediction error criterion.

Savitzky–Golay (SG) filtering is a classical signal smoothing technique based on the local least squares approximation of the analyzed signal by a linear combination of known functions of time (originally — powers of time, which corresponds to polynomial approximation). It is shown that the regularized version of the SG algorithm can be successfully applied to identification of time-varying finite impulse response (FIR) systems. Such a solution is possible owing to the recently proposed preestimation technique, which converts the problem of identification of a time-varying FIR system into the problem of smoothing of the appropriately generated preestimates of system parameters. The resulting fast regularized local basis function estimators, optimized using the empirical Bayes approach, have very good parameter tracking capabilities, favorably comparing with the state-of-the-art in terms of accuracy, computational complexity and numerical robustness.

When estimating the correlation/spectral structure of a locally stationary process, one has to make two important decisions. First, one should choose the so-called estimation bandwidth, inversely proportional to the effective width of the local analysis window, in the way that complies with the degree of signal nonstationarity. Too small bandwidth may result in an excessive estimation bias, while too large bandwidth may cause excessive estimation variance. Second, but equally important, one should choose the appropriate order of the spectral representation of the signal so as to correctly model its resonant structure–when the order is too small, the estimated spectrum may not reveal some important signal components (resonances), and when it is too high, it may indicate the presence of some nonexistent components. When the analyzed signal is not stationary, with a possibly time-varying degree of nonstationarity, both the bandwidth and order parameters should be adjusted in an adaptive fashion. The paper presents and compares three approaches allowing for unified treatment of the problem of adaptive bandwidth and order selection for the purpose of identification of nonstationary vector autoregressive processes: the cross-validation approach, the full cross-validation approach, and the approach that incorporates the multivariate version of the generalized Akaike’s final prediction error criterion. It is shown that the latter solution yields the best results and, at the same time, is very attractive from the computational viewpoint.

Dynamic weighing, i.e., weighing of objects in motion, without stopping them on the weighing platform, allows one to increase the rate of operation of automatic weighing systems, used in industrial production processes, without compromising their accuracy. Since the classical identification-based approach to dynamic weighing, based on the second-order mass–spring–damper model of the weighing system, does not yield satisfactory results when applied to conveyor belt type checkweighers, several extensions of this technique are examined. Experiments confirm that when appropriately modified the identification-based approach becomes a reliable tool for dynamic mass measurement in checkweighers.

The problem of off-line identification of a nonstationary autoregressive process with a time-varying order and a time-varying degree of nonstationarity is considered and solved using the parallel estimation approach. The proposed parallel estimation scheme is made up of several bidirectional (noncausal) exponentially weighted lattice algorithms with different estimation memory and order settings. It is shown that optimization of both settings can be carried out by means of minimization of the locally evaluated accumulated forward/backward prediction error statistic.

In this paper, a new solution to the problem of elimination of impulsive disturbances from audio signals, based on the matched filtering technique, is proposed. The new approach stems from the observation that a large proportion of noise pulses corrupting audio recordings have highly repetitive shapes that match several typical "patterns". In many cases a representative set of exemplary pulse waveforms can be extracted from the episodes of silence preceding and succeeding the recorded audio material. Based on such a set, a relatively small number of typical noise patterns, called click templates, can be established. To localize noise pulses, the appropriately modified click templates can be correlated with the sequence of one-step-ahead prediction errors yielded by the model-based signal predictor. It is shown that template matching is an efficient and computationally affordable disturbance localization technique - when combined with the classical detection method based on autoregressive modeling, it can improve restoration results. Since click templates can be created for a particular set of recordings, obtained using a particular audio equipment, an important feature of the proposed approach is its source adaptivity. Even though the paper is focused on restoration of archive recordings, the proposed approach is useful in a much wider context, e.g., it can be applied to elimination of impulsive disturbances corrupting telecommunication channels.

The paper presents a new, two-stage approach to identification of linear time-varying stochastic systems, based on the concepts of preestimation and postfiltering. The proposed preestimated parameter trajectories are unbiased but have large variability. Hence, to obtain reliable estimates of system parameters, the preestimated trajectories must be further filtered (postfiltered). It is shown how one can design and optimize such postfilters using the basis function framework. The proposed solution to adaptive tuning of postfilter settings is based on parallel estimation and cross-validatory analysis. When compared with the classical solutions to the problem of parameter tracking, the new approach offers, without compromising good tracking performance, significant computational savings, higher numerical robustness and greater flexibility.

The aim of this study was to evaluate the risk factors of relapse and treatment-related deaths in acute lymphoblastic leukemia (ALL) in children residing in Poland. A total of 1872 patients with newly diagnosed ALL, treated according to the ALL IC-BFM 2002 protocol in 14 Polish pediatric hematology centers from 2002 to 2012 were included in the study. Three-hundred eighty-four patients experienced treatment failure. The last follow-up was 31 December, 2016. Univariate analysis identified factors in each risk group that were significantly different between children whose treatment failed and those who remained in the first remission. Multivariate analysis demonstrated that only the age of 10 years or over at primary diagnosis in the high-risk group was an adverse prognostic factor. To facilitate the analysis, patients were divided into three groups: relapsed children who survived; relapsed children who died; children without relapse who died due to toxicity. Our analysis showed that age older than 10 years is a particular risk factor for the failure of first-line of treatment, both in terms of relapse and treatment-related mortality.

Regulatory T-cells (Tregs) are a very important subtype of lymphocytes when it comes to self-control in the human immunological system. Tregs are decisive not only in the protection against destruction of own tissues by autoimmune immunocompetent cells but also in the immunological answer to developing cancers. On the other hand, Tregs could be responsible for the progression of acute and chronic leukemias. In our study, we review publications available in the PUMED database concerning acute leukemia, with a particular emphasis on child’s leukemias. The percentage of regulatory T-lymphocytes in peripheral blood and bone marrow was elevated compared to those in healthy individuals and correlated with progressive disease. Regulatory T-cells taken from children diagnosed with leukemia showed a higher suppressive capability, which was confirmed by detecting elevated levels of secreted IL-10 and TGF-beta. The possibility of pharmacological intervention in the self-control of the immunological system is now under extensive investigation in many human cancers. Presumably, Treg cells could be a vital part of targeted therapies. Routine Treg determination could be used to assess the severity of disease and prognosis in children with acute lymphoblastic leukemia. This proposition results from the fact that in some studies, higher percentage of Treg cells in peripheral blood was demonstrated. However, observations confirming these facts are scarce; thus, extrapolating them to the population of children with hematological malignancies needs to be verified in additional studies.

CD4+CD25highCD127low/−FoxP3+ regulatory T cells (Tregs) are currently under extensive investigation in childhood acute lymphoblastic leukemia (ALL) and in other human cancers. Usually, Treg cells maintain the immune cell homeostasis. This small subset of T cells has been, in fact, considered to be involved in the pathogenesis of autoimmune diseases and progression of acute and chronic leukemias. However, whether Treg dysregulation in CLL and ALL plays a key role or it rather represents a simple epiphenomenon is still a matter of debate. Treg cells have been proposed as a prognostic indicator of the clinical course of the disease and might also be used for targeted immune therapy. Our study revealed statistically higher percentage of Treg cells in the bone marrow than in peripheral blood in the group of 42 children with acute lymphoblastic leukemia. By analyzing Treg subpopulations, it was shown that only memory Tregs in contact with leukemic antigens showed statistically significant differences. We noticed a low negative correlation between Treg cells in the bone marrow and the percentage of blasts (R=−0.36) as well as a moderate correlation between Treg cells in the bone marrow and Hb level (R=+0.41) in peripheral blood before therapy. The number of peripheral blood blasts on day 8th correlates negatively (R=−0.36) with Tregs. Furthermore, statistical analysis revealed low negative correlation between the number of Tregs in the bone marrow and the minimal residual disease measured on day 15th, the percentage of blasts in the bone marrow and leukocytosis after 15 days of chemotherapy. These results indicate the influence of Tregs on the final therapeutic effect.

Background Chronic myeloid leukemia (CML) constitutes only 2-3% of all leukemias in pediatric patients. Philapelphia chromosome and BCR-ABL fusion are genetic hallmarks of CML, and their presence is crucial for targeted molecular therapy with tyrosine kinase inhibitors (TKIs), which replaced hematopoietic stem cell transplantation (HSCT) as a standard first-line therapy. The disease in pediatric population is rare, and despite molecular and clinical similarities to CML in adults, different approach is needed, due to the long lifetime expectancy and distinct developmental characteristics of affected children. Objectives The objective of this study is to evaluate treatment with imatinib in Polish pediatric patients with CML. Material and methods We analyzed the results of treatment with imatinib in 57 pediatric patients (June 2006 - January 2016) from 14 Polish pediatric hematology and oncology centers. Results In the study group, 40 patients continued imatinib (median follow-up: 23.4 months), while in 17 the treatment was terminated (median follow-up: 15.1 months) due to therapy failure. In the latter group, 13 patients underwent HSCT, while 4 switched to second-generation TKIs. The 5-year overall survival rate (OS) in the study group was 96%, and the 5-year event-free survival (EFS) was 81%. Conclusions Our results confirm that the introduction of TKI therapy has revolutionized the treatment of CML in the pediatric population by replacing the previous method of treatment with HSCT and allowing a high percentage of OS and EFS.

Exhaled breath condensate (EBC) is receiving increased attention as a novel, entirely non-invasive technique for collecting biomarker samples. This increased attention is due to the fact that EBC is simple, effort independent, rapid, can be repeated frequently, and can be performed on young children and patients suffering from a variety of diseases. By having a subject breathe tidally through a cooling system for 15-20 min, a sufficient amount of condensate is collected for analysis of biomarkers in clinical studies. However, bioanalysis of EBC involves an unavoidable sample preparation step due to the low concentration of its components. Thus, there is a need for a new and more sensitive analytical method of assessing EBC samples. While researchers have considered analyses of single and small quantities of amino acids - for example, those connected with leukemia - no one has previously attempted to simultaneously analyze a panel of 23 amino acids. Moreover, the present study is well-justified, as prior studies focusing on single amino acids and leukemia at the moment of diagnosis and during chemotherapy (33 days of treatment) are inconsistent. In the present study, amino acids were separated using an XBridge Amide column (3 mm × 100 mm, 3.5 μm). The mobile phase consisted of 10 mM of ammonium buffer in water with a pH of 3 (Phase A) and 10 mM ammonium buffer in acetonitrile (Phase B) under gradient program elution. The analytes were detected in electrospray positive ionization mode. Under optimal conditions, the proposed method exhibited limits of quantification (LOQ) in the range of 0.05-0.5 ng/mL, and good linearity, with the determination coefficient (R2) falling between 0.9904 and 0.9998. The accuracy in human exhaled breath condensate samples ranged between 93.3-113.3% for the 23 studied amino acids, with intra- and inter-day coefficient of variation (CVs) of 0.13-9.92% and 0.17-10.53%, respectively. To demonstrate the liquid chromatography with hydrophilic interaction with electrospray source coupled to tandem mass spectrometry (LC-HILIC-ESI-MS/MS) method's applicability for biomedical investigations, it was verified and applied to determine amino acids in pediatric patients with leukemia. These tests confirmed that glutamine, arginine, homoarginine, asparagine, histidine, methionine, proline, hydroxyproline, threonine, tyrosine, and valine were present in significantly higher levels in pediatric leukemia patients than in the healthy control group. The developed assay is an attractive alternative to standard analytical methods, because it allows for the non-invasive, fast, sensitive, and reliable analysis of amino acids without derivatization in EBC.

Conveyor belt type checkweighers are complex mechanical systems consisting of a weighing sensor (strain gauge load cell, electrodynamically compensated load cell), packages (of different shapes, made of different materials) and a transport system (motors, gears, rollers). Disturbances generated by the vibrating parts of such a system are reflected in the signal power spectra in a form of strong spectral peaks, located usually in the lower frequency range. Such low frequency components overlap in the frequency domain with the useful signal and it is very difficult to eliminate them. The conventional way of suppressing disturbances is via low-pass filtering of the signal obtained from the load cell. However, if the speed of the conveyor belt is high, the response of the applied filter may not settle fast enough to enable accurate weighing of objects in motion, i.e., without stopping them on the weighing conveyor. Since attempts to overcome this problem using classical linear time-invariant low-pass filtering fail for high belt speeds, the paper presents and verifies experimentally a new approach, based on time-variant low-pass filtering. It is shown that, when properly tuned, the proposed time-variant filter fulfills the measurement accuracy requirements for a wide range of operating conditions.

SUMMARY SONIC (self-optimizing narrowband interference canceler) is an acronym of a recently proposed active noise control algorithm with interesting adaptivity and robustness properties. SONIC is a purely feedback controller, capable of rejecting nonstationary sinusoidal disturbances (with time-varying amplitude and/or frequency) in the presence of plant (secondary path) uncertainty. We show that although SONIC can work reliably without access to a reference signal, even when the frequency of the disturbance is unknown and possibly time varying, the algorithm can take advantage of such additional source information. Unlike classical hybrid solutions, the reference signal is used only to extract information about the instantaneous frequency of the disturbance. The advance-time advantage, available because the acoustic delay in the system is larger than the electrical delay, allows one to incorporate in the control loop a smoothed, and hence more accurate, frequency estimate. This increases the attenuation efficiency of SONIC and widens its operating range—the modified algorithm can be safely used in the presence of rapid frequency changes. Copyright © 2013 John Wiley & Sons, Ltd.

Background. Hematopoietic stem cell transplantation (HSCT) is an established procedure for many acquired and congenital disorders of the hematopoietic system, including malignancies, bone marrow failure syndromes, disorders of the immune system, and metabolic disorders. Objective. Analysis of results of hematopoietic stem cell transplantations performed over a period of 12 years in a single pediatric center. Patients and methods. All transplants performed between 2003 and 2015 in the Department of Pediatric Hematology and Oncology in Bydgoszcz were included in this analysis. The results of therapy with stem cell transplantation were analyzed in three time periods: 2004-2007, 2008-2011 and 2012-2015. Results. A total number of transplants was 318, including 132 auto-HSCT and 186 allo-HSCT. Among allogeneic transplants, 68 were done from matched-sibling donor and 118 from alternative donor. The mean survival for all patients estimated by Kaplan-Meier method was 8.1 years. Probability of overall survival (pOS) after all transplants was 0.64±0.03. pOS after allo-HSCT was 0.62±0.04, and 0.67±0.05 after auto-HSCT. Overall survival for patients transplanted in the second (2008-2011) and third (2012-2015) time period was comparable both for auto- and allo-HSCT. However, it was significantly higher than for patients transplanted in the first period of time (2004-2007) for all patients, and for those undergoing auto-HSCT. In allo-HSCT patients, in spite of increase of over 20% in pOS (43% vs 66% vs 64% in respective time periods), the difference was not statistically significant. Conclusion. Presented results of HSCT obtained in our center are comparable with those from other international registries and centers. Wstęp. Transplantacja komórek krwiotwórczych (HSCT) jest ważną metodą terapeutyczną w wielu wrodzonych i nabytych chorobach, w tym nowotworowych, zespołach niewydolności szpiku oraz zaburzeniach immunologicznych i metabolicznych. Celem pracy jest analiza wyników HSCT w pojedynczym ośrodku pediatrycznym w okresie 12 lat. Pacjenci i metodyka. Analizie poddano wyniki przeszczepień wykonanych w latach 2003-2015 w Klinice Pediatrii, Hematologii i Onkologii w Bydgoszczy. Transplantacje analizowano w trzech przedziałach czasowych: 2004-2007, 2008-2011 oraz 2012-2015. Wyniki. Wykonano 318 HSCT, w tym 186 alloge-nicznych (68 zgodnych rodzinnych i 118 od dawców alternatywnych) oraz 132 autologiczne. Średnie przeżycie po HSCT, wyznaczone metodą Kaplana-Meiera wyniosło 8,1 lat. Całkowite prawdopodobieństwo przeżycia (pOS) wyniosło 0,64±0,03; pOS po allo-HSCT wynosi 0,62±0,04, a po auto-HSCT 0,67±0,05. Nie wykazano znamiennych różnic w pOS zarówno po allo-HSCT, jak i po auto-HSCT pomiędzy drugim (2008-2011) i trzecim (2012-2015) analizowanym okresie. Jednakże, pOS było wyższe w dru-gim i trzecim okresie w stosunku do okresu pierwszego (2004-2007), zarówno dla wszystkich pacjentów, jak i u pacjentów po auto-HSCT. W grupie pacjentów allo-HSCT, uzyskano wzrost pOS o ponad 20% (43% vs 66% vs 64% w kolejnych przedziałach czasu; ns). Wnioski. Wyniki HSCT uzyskiwane aktualnie w na-szym ośrodku są porównywalne z wynikami podawanymi w międzynarodowych rejestrach.

In this paper we consider the problem of noncausal identification of nonstationary, linear stochastic systems, i.e., identification based on prerecorded input/output data. We show how several competing weighted least squares parameter smoothers, differing in memory settings, can be combined together to yield a better and more reliable smoothing algorithm. The resulting parallel estimation scheme automatically adjusts its smoothing bandwidth to the unknown, and possibly time-varying, rate of nonstationarity of the identified system. It also allows one to account for the distribution of measurement noise, and in particular – to cope with heavy-tailed disturbances, such as Laplacian noise, or light-tailed disturbances, such as uniform noise.

The problem of identification of linear quasi-periodically varying systems is considered. This problem can be solved using generalized adaptive notch filtering (GANF) algorithms. It is shown that accuracy of system parameter estimation can be increased if the results obtained from GANF are further processed using a cascade of appropriately designed filters. The resulting generalized adaptive notch smoothing (GANS) algorithms can be employed in offline applications where causality constraints do not apply. When the instantaneous frequency of parameter changes varies in a sufficiently smooth manner, the proposed GANS algorithm, based on a new, quasi-linear model of frequency drift, outperforms the existing solutions.

Generalized adaptive notch filters (GANFs) are used for identification/tracking of quasi-periodically varying dynamic systems and can be considered an extension, to the system case, of classical adaptive notch filters. The tracking properties of a GANF algorithm depend on two adaptation gains, which should be chosen so as to match the degree of nonstationarity of the identified system. First, an analytical study of a tracking performance of a real-valued GANF algorithm is presented. Then, based on the obtained theoretical results, a self-optimizing algorithm is proposed, capable of automatic tuning of its adaptation gains. The paper is an extension of the previous work devoted to complex-valued GANF algorithms.

A simple and sensitive method using dispersive liquid-liquid microextraction (DLLME) followed by liquid chromatography coupled to mass spectrometry (LC-MS) with a hydrophilic interaction chromatography (HILIC) column was developed for the simultaneous determination of 13 compounds of different polarities, comprising monoamine neurotransmitters (dopamine, norepinephrine, epinephrine and serotonin) along with their respective precursors and metabolites, in human urine samples. The microextraction procedure was based on the fast injection of a mixture of ethanol (disperser solvent) and dichloromethane (extraction solvent) into a human urine sample, forming a cloudy solution in the Eppendorf tube. After centrifugation, the sedimented phase was collected and subsequently analyzed by LC-HILIC-MS in about 12min without a derivatization step. The separation was performed on an XBridge Amide™ BEH column 3.0×100mm, 3.5mm and the mobile phase consisted of phase A: 10mM ammonium formate buffer in water pH 3.0 and phase B: 10 mM ammonium formate buffer in acetonitrile, under gradient program elution. Tyrosine, tryptophan, 5-hydroxytryptophan, dopamine, epinephrine, norepinephrine, serotonin, 3-methoxytyramine, 5-hydroxyindole-3-acetic acid, 3,4-dihydroxy-l-phenylalanine and norvaline (internal standard) were detected in the positive ionization mode. While vanillylmandelic acid, homovanillic acid, 3,4-dihydroxyphenylacetic acid and 3,4-dihydroxybenzylamine (internal standard) were detected in the negative ionization mode. Parameters influencing DLLME and LC-HILIC-MS were investigated. Under the optimum conditions, the proposed method exhibited a low detection limit (5-10ngmL(-1)), and good linearity with R between 0.9991 and 0.9998. The recoveries in human urine samples were 99.0%±3.6%. for the 13 studied biogenic amines with intra- and inter-day RSDs of 0.24-9.55% and 0.31-10.0%, respectively. The developed DLLME-LC-MS method could be successfully applied for the determination of trace amounts of polar endogenous compounds, such as neurotransmitters, in human urine samples, including samples with a reduced volume obtained from pediatric patients.

Bias (lag) errors seriously limit tracking capabilities of adaptive filters. We show that frequency biases, which arise in generalized adaptive notch filtering algorithms, can be reduced if the frequency estimates are appropriately filtered. This allows one to build estimation schemes with improved tracking capabilities.

The problem of either elimination or extraction of an unknown number of nonstationary complex sinusoidal signals burried in noise is considered. We derive a class of adaptive notch filtering algorithms which can be efficiently (almost transientless) started, or restarted, using the results of local nonparametric, periodogram-based signal analysis.

The problem of identification/tracking of quasi-periodically varying processes is considered. Two solutions to this problem are presented, First the global search algorithm is derived. Then its decoupled version. with a highly parallel computational structure, is proposed.

Background Currently, there are three major maturational stages of CD19 antigen expressing B-cell precursors (hematogones). In B-cell precursor acute lymphoblastic leukemia (BCP-ALL), the malignant counterpart of hematogones, the leukemic blasts share common phenotypic features. The aim of the study was to enumerate the actual differences between the leukemic blasts in the CD10+ and CD10− subgroups of BCP-ALL and hematogones by assessing the expression of the antigens: TdT, CD34, CD45, CD10, CD38, CD20 and CD22. Methods To enable quantitative assessment of antigen expression on the different cell types, an objective scale of antigen expression was developed, the basis of which was direct fluorescence measurement using multicolor flow cytometry. Results All cases of CD10+ BCP-ALL clustered with type 1 hematogones. Among CD10−- BCP-ALL subgroup, 54.5%, 27.3% and 18.2% of cases clustered with type 1, 2 and 3 hematogones, respectively. In contrast to the CD10− blasts, the CD10+ blasts exhibited significantly higher levels of TdT, CD22, CD34 and CD20 expression. Conversely, CD10− blasts showed significantly higher expression of CD45 than CD10+ blasts, and a higher rate of CD45 antigen overexpression than CD10+ blasts (54.5% vs. 14.9% of cases, respectively). Conclusions Multiparameter flow cytometry combined with the use of absolute antigen expression scale based on direct fluorescence measurement, has enabled a clear distinction between blasts in BCP-ALL cases and their normal counterparts. This novel and previously undescribed method has allowed the comparative analysis of antigen expression between leukemic blasts and different types of their normal counterparts. © 2014 International Clinical Cytometry Society

The problem of elimination of a measurement noise and impulsive disturbances from time-varying autoregressive signals is considered. The combined signal filtering / parameter tracking / outlier elimination algorithms proposed in the paper borrow their form from the "prototype" algorithm based on extended Kalman filtering (EKF). While the original EKF solution is computationally quite involved the EKF-like algorithms are much simpler and easier to implement. The new approach was successfully applied to restoration of archive audio recordings.

This paper presents a novel method for dynamic weighing of cars making up a freight train. The proposed algorithms allow for automatic and accurate estimation of weight of separate cars without the need to uncouple them nor to stop them on the measuring platform. The new approach is illustrated with both the results of computer simulations and real experiments.